No full-text available
To read the full-text of this research,
you can request a copy directly from the authors.
Effects of a low-energy diet followed by a compensatory diet on growth, puberty and milk production in dairy heifers
Abstract
Six-month-old Israeli Holstein heifers were fed on a low-energy (LE) diet with corn straw as the main feed component during the 4 months of summer, followed by a high-energy, high-protein diet for compensatory growth during the 2 months of autumn. During the same period a control group was fed to support an average daily gain of 0.65 kg. During the LE phase, the mean daily gains in heart girth, body weight and hip height were 51 to 67% lower than those of the control group. During the compensatory phase, mean daily gains in body weight, hip height and heart girth group were 197 to 225% times greater than in the control group. By the end of the compensatory phase the experimental group had the same mean body weight as the control group, but the mean hip height of the heifers was 2 cm shorter. Puberty was attained by the experimental group one month later than in the control group, but at the same body weight. Milk production was similar in the two groups. The efficiency of the metabolisable energy intake for body weight gain in both treatments was discussed.
... Compensatory growth is the phenomenon wherein the re-alimentation of previously underfed animals results in a greater than predicted rate of gain in 'stunted' tissues (i.e. greater feed conversion efficiency; Sheehy and Senior 1942;Ledin 1984;Park et al. 1987;Barash et al. 1994). In a series of experiments to determine the effect of the 'stair-step program' of heifer nutrition, heifers were alternated between consuming 15-30% less than predicted requirements of a balanced ration for periods of 3-4 months and 20-30% more than requirement for periods of 2-3 months (Park et al. 1987(Park et al. , 1988(Park et al. , 1989Choi et al. 1997Choi et al. , 1998Ford and Park 2001). ...
... Ford and Park 2001). Others have confirmed the presence of compensatory growth in stature in dairy heifers, when 2 months of ad libitum feeding followed 4 months of a restricted allowance (Peri et al. 1993;Barash et al. 1994). However, the effect on milk production was not consistent; Barash et al. (1994) reported no effect of rearing method on milk production, while Peri et al. (1993) identified a 16% increase in milk yield and a 9% and 2% increases in milk fat and protein yields, respectively. ...
... Others have confirmed the presence of compensatory growth in stature in dairy heifers, when 2 months of ad libitum feeding followed 4 months of a restricted allowance (Peri et al. 1993;Barash et al. 1994). However, the effect on milk production was not consistent; Barash et al. (1994) reported no effect of rearing method on milk production, while Peri et al. (1993) identified a 16% increase in milk yield and a 9% and 2% increases in milk fat and protein yields, respectively. Similarly, Ford and Park (2001) reported 1.5-fold increase in growth efficiency (Lwt gain/ DM intake) and 21% and 15% increases in firstand secondlactation yield, respectively, in animals subjected to repeating periods of restriction and re-alimentation; however, there were only four and three cows per treatment, respectively, in each of these lactations, and the milk-production results should be viewed cautiously. ...
Dairy heifer growth and liveweight at first calving are regarded as important management variables affecting profitability and animal welfare. However, the appropriateness of heifer growth rate targets for different farming systems is not clear. Retrospective assessments of the association between heifer liveweight and subsequent productivity indicate significant benefits in milk production and, even, reproduction from increasing liveweight at breeding and first calving. However, prospective interventionist experiments do not concur, with very variable effects of liveweight at breeding on milk production and with only limited evidence of a positive effect of first-calving liveweight on first-lactation milk yield. In addition, any benefit in the first lactation is not evident in subsequent lactations in the limited number of long-term studies reported. Pre-weaning nutrition and average daily weight gain are areas of increasing interest, with lifelong increases in milk production resulting from accelerated growth rates during the first 8 weeks of life, indicating a possible significant return from a short-term investment. This could be one reason for the inconsistent effects of heifer liveweight at breeding and first lactation on milk production. Although the effect of pre-weaning average daily gain on heifer liveweight is short-lived, a recent meta-analysis indicated that pre-weaning average daily gain explains 22% of the variation in first-lactation milk production. Whether these differences in animal physiology have relevance in grazing systems, wherein heifers and cows do not consume sufficient nutrients to reach their potential, requires investigation. Despite considerable extension efforts over successive decades, current evidence indicates that failure to provide the new-born calf with sufficient high-quality colostrum is common. To understand the reasons for suboptimal colostrum feeding requires social research, with appropriate extension strategies developed to elicit practice change. Although there can be little doubt regarding the importance of heifer rearing to the profitability and sustainability of the farming business, the collective literature points to a failure of retrospective analyses in determining the cause of poor heifer performance. In reality, it is likely to be a combination of factors. The objective of this review is to investigate the effect of liveweight gain at various stages of the growth cycle of the heifer on the milk-production capacity of the lactating animal.
... Compensatory growth is the phenomenon wherein the re-alimentation of previously underfed animals results in a greater than predicted rate of gain in 'stunted' tissues (i.e. greater feed conversion efficiency, Sheehy and Senior 1942, Ledin 1984, Park et al. 1987, Barash et al. 1994. In a series of experiments to determine the effect of the "stair-step programme" of heifer nutrition, heifers were alternated between consuming 15-30% less than predicted requirements of a balanced ration for periods of three to four months and 20-30% more than requirement for periods of two to three months (Park et al. 1987, Ford and Park 2001. ...
... In general, the regime resulted in greater feed conversion efficiency, greater mammary secretory development, and generally resulted in greater milk production (~10%). Others have confirmed the presence of compensatory growth in stature in dairy heifers, when two months of ad libitum feeding followed four months of a restricted allowance (Peri et al. 1993, Barash et al. 1994. However, the effect on milk production was not consistent; (Barash et al. 1994) reported no effect of rearing method on milk production, while (Peri et al. 1993) identified a 16% increase in milk yield and a 9% and 2% increase in milk fat and protein yields, respectively. ...
... Others have confirmed the presence of compensatory growth in stature in dairy heifers, when two months of ad libitum feeding followed four months of a restricted allowance (Peri et al. 1993, Barash et al. 1994. However, the effect on milk production was not consistent; (Barash et al. 1994) reported no effect of rearing method on milk production, while (Peri et al. 1993) identified a 16% increase in milk yield and a 9% and 2% increase in milk fat and protein yields, respectively. Similarly, Ford and Park (2001) reported 1.5 fold increase in growth efficiency (Lwt gain/DM intake) and a 21% and 15% increase in first and second lactation yield, respectively, in animals subjected to repeating periods of restriction and realimentation. ...
Dairy heifer growth and live weight at first calving are regarded as important management variables affecting profitability and animal welfare. However, the appropriateness of heifer growth rate targets for different farming systems is not clear. Retrospective assessments of the association between heifer live weight and subsequent productivity indicate significant benefits in milk production and, even, reproduction from increasing live weight at breeding and first calving. Prospective interventionist experiments do not concur, however, with very variable effects of live weight at breeding on milk production and only limited evidence of a positive effect of first calving live weight on first lactation milk yield. In addition, any benefit in the first lactation is not evident in subsequent lactations in the limited number of long-term studies reported. Pre-weaning nutrition and average daily weight gain are areas of increasing interest, with lifelong increases in milk production resulting from accelerated growth rates during the first eight weeks of life indicating possible significant return from a short-term investment. This could be one reason for the inconsistent effects of heifer live weight at breeding and first lactation on milk production. Although the effect of pre-weaning average daily gain on heifer live weight is short-lived, a recent meta-analysis indicates that pre-weaning average daily gain explains 22% of the variation in first lactation milk production. The validity of these results in grazing systems requires investigation. Despite considerable extension efforts over successive decades, current evidence indicates that failure to provide the new-born calf with sufficient high quality colostrum is common. To understand the reasons for suboptimal colostrum feeding requires social research, with appropriate extension strategies developed to elicit practice change. Although there can be little doubt regarding the importance of heifer rearing to the profitability and sustainability of the farming business, the collective literature points to a failure of retrospective analyses in determining the cause of poor heifer performance. In reality, it is likely to be a combination of factors. The most likely nutritional factors are discussed in this review. BACKGROUND Dairy heifer growth rate and live weight (Lwt) at first calving are regarded as important benchmarks in farm management (Sejrsen and Purup, 1997) because lower Lwt heifers are at a greater risk of dystocia at first calving (Mee et al. 2008), produce less milk, and have a shorter lifespan in the herd (Archbold et al. 2012, McNaughton and Lopdell 2013). Also, greater heifer growth rates can theoretically lead to an earlier breeding event and reduce the time that the heifer spends in a non-productive state (Capuco et al. 1995, Sejrsen and Purup 1997). However, there is evidence that excessive growth rates at key periods of development are associated with impaired mammary development and reduced milk production (Harrison et al. 1983, Sejrsen et al. 1983, Sejrsen and Purup 1997). Therefore, the rate of growth must be planned to ensure that heifers become productive early, without undermining lifetime productivity. To complicate matters, recommendations on optimum first-calving Lwt vary widely. In high concentrate intensive feeding systems, Holstein-Friesian cows achieve 550 to 650 kg of Lwt before first calving (Keown and Everett, 1986; Heinrichs, 1993; Hoffman, 1997), while a more modest first-calving Lwt is accepted in pasture-based systems for the same breed (450 to 550 kg; McLean and Freeman 1996, Holmes et al. 2002). Troccon (1993) recommended that a heifer's Lwt at first calving should be 90% of her mature Lwt. However, how should mature Lwt be determined? The average of the herd does not account for the heifer's individual genetics and is heavily influenced by the environment in which the herd is managed. In addition, (Archbold et al. 2012) reported that low Lwt heifers at 15 months remained low Lwt heifers at first calving and as cows up to at least their third lactation. In fact, in their dataset, all heifers were 85% of their five year old Lwt at first calving, irrespective of the quartile of 15 month Lwt they belonged to; herd mature Lwt could, therefore, be a function of historical heifer growth trajectory and projecting heifer growth on data from cows that were poorly grown as heifers
... Then, compensation results mainly from higher feed intake. There is limited literature reporting changes of live weight gain and metabolic adaptations during the compensatory growth phase in cattle [27,28,29,30,31,32,33]. Compensatory growth rates are cubic in nature (Fig. 2). ...
... growth -Hormone level control ) ϫ Energy intake comp. growth Energy intake control Such a method was used to evaluate changes of plasma hormone concentrations in compensating animals [27,22,28,29,30,31,32,33,7,19]. The results are shown in Fig. 3 to 7. ...
... One of the characteristics of compensatory growth is thus a sharp decrease of the ratio GH to insulin [22]. However, Fig. 4 shows that most studies reported higher GH Fig. 3. Evolution of the absolute or weighed differences in plasma insulin between compensating and control animals, calculated from 10 literature references [27,22,28,29,30,31,32,33,7,19]. Weighed differences were obtained by multiplying the absolute differences with the ratio of the energy provided to the compensating animals to that offered to controls. ...
Growth is an integrated process, resulting from the response of cells dependent on the endocrine status and nutrient availability. During feed restriction, the production and secretion of growth hormone (GH) by the pituitary gland are enhanced, but the number of GH receptors decreases. Changes of GH binding proteins induce GH resistance and are followed by reduced insulin-like growth factor-I (IGF-I) secretion. On the other hand, high circulating levels of GH enhance the mobilization of fatty acids, which are used to support energy requirements. Thus, when feed restriction in growing animals is moderate, there is mainly protein but barely fat accretion. By contrast, a severe feed restriction enhances the release of catabolic hormones and stimulates, from muscle cells, the liberation of amino acids, which are used by hepatocytes for gluconeogenesis. During refeeding and compensatory growth, the secretion of insulin is sharply enhanced and plasma GH concentrations remain high. This situation probably allows more nutrients to be used for growth processes. The role of plasma IGF-I during compensatory growth is not clear and must be explained in connection with changes of its binding proteins. Thyroxin and 3,5,3'-triiodothyronine seem to have a permissive effect on growth. The simultaneous occurrence of puberty with refeeding can exert a synergistic effect on growth. Initially, compensatory growth is characterized by the deposition of very lean tissue, similar as during feed restriction. This lasts for some weeks. Then, protein synthesis decreases and high feed intake leads to increased fat deposition.
... Something similar occurs in rats, where puberty occurs once a critical BW is reached (24) . Although this theory was extrapolated and supported by information obtained with heifers of beef (25)(26) (27) and dairy breeds (28) (29) (30) , other studies reported that heifers maintained under different feeding plans reached puberty with different BW (16)(31) (32) . ...
... Age and BW at puberty presented a high positive linear correlation (r = 0.56, P < 0.01; Figure 1), which is in agreement with studies that reported that heifers maintained under different managements reached puberty with different BW (16) (32) , and in contrast to the hypothesis that cyclic activity begins at the moment that heifers reach a target BW (28) (29) (30) . The correlation between ADG and age at puberty was also very high and negative (r = -0.58, ...
Management practices during the rearing of dairy heifers should allow an adequate body growth and reproductive development to attain puberty several months before the first conception. Proposed target age and body weight (BW) at first calving for Holstein heifers are between 22-24 months and 82% of mature BW, respectively, for which heifers must conceive at around 15 months of age with 60% of their mature BW. Pre- and postweaning feeding level has effects on feed efficiency, behavior, energy metabolism and body and reproductive development, while social environment during rearing, specifically the social dominance and social regroupings, is known to affect energy metabolism, feeding behavior and body and reproductive development of the heifer. In Uruguay, the information published regarding the management of the dairy heifer is scarce. The aim of this review is to briefly assess the main factors affecting the onset of puberty, and to present an integrative approach of the information generated in Uruguay regarding the effects of modifying the feeding level and social environment during the rearing period on body development, metabolism, and onset of puberty in dairy heifers. In addition, we make a proposal of knowledge gaps that should be addressed in future studies.
... Dietary restriction has a profound influence on the biology and health of animals including retardation of ageing and reduction of cancer incidence (Weindruch & Walford, 1988). While imposition of excessive dietary restriction on growing animals may inhibit normal development of the mammary gland, a well-controlled dietary energy restriction regimen positively effects mammary growth, development and subsequent lactation in rats (Park et al. 1988) and bovine species (Park et al. 1989;Peri et al. 1993;Barash et al. 1994;Choi et al. 1997). The stair-step (phased) compensatory nutrition regimen proposed and studied in our laboratory is designed so that development of mammary tissues is minimal during an energy restriction phase, while a compensatory growth phase immediately following energy restriction stimulates rapid and fuller development of the mammary gland. ...
... The stair-step (phased) compensatory nutrition regimen proposed and studied in our laboratory is designed so that development of mammary tissues is minimal during an energy restriction phase, while a compensatory growth phase immediately following energy restriction stimulates rapid and fuller development of the mammary gland. Studies from our laboratory (Park et al. 1988(Park et al. , 1989(Park et al. , 1997, as well as from others (Barash et al. 1994;Choi et al. 1997), show that lactation performance is increased by 8-17% in animals reared on a compensatory nutrition regimen. ...
The proper use of a time-dependent and controlled nutrition regimen during the hormone-sensitive growth phase before first parturition can significantly affect mammary growth and subsequent lactation performance. The objective of the present study was to determine if a compensatory nutrition regimen improves lactation performance by affecting proliferation and apoptosis of mammary epithelial cells. Forty female rats (7 weeks of age, average weight 148 g) were assigned to either (1) control, free access to diet or (2) stair-step compensatory nutrition regimen, an alternating 3-4-week schedule beginning with an energy-restricted diet (31.2% restriction) for 3 weeks, followed by the control diet for 4 weeks. Estimated milk yield was greater (P < 0.05) on day 15 of lactation in the compensatory nutrition group than in the control group. Mammary cell proliferation values were 1.4- and 2.7-fold greater in mammary tissue from the compensatory group during pregnant and early lactating stages respectively, compared with those from the control group. Ornithine decarboxylase (EC 4.1.17) mRNA was 24% higher (P < 0.05) in mammary tissues of rats from the compensatory nutrition group during pregnancy than in those from the control group. These results indicate that the compensatory nutrition regimen imposed during the peripubertal growth phase stimulated mammary epithelial cell proliferation and improved lactation performance.
... Likewise, Peri et al. (1993) found that 6-mo-old Holstein heifers subjected to a growth restriction-compensation nutritional regimen produced 16% more milk during a 250-d lactation period than continuous-growth heifers. In contrast, Barash et al. (1994) found that 7-mo-old Holstein heifers subjected a growth restriction-compensation nutritional regimen comparable to that used by Peri et al. (1993) produced milk yields similar to those of continuous-growth heifers. ...
... Differences in the CP to ME ratio of the diets fed during the growth restriction periods may have contributed to the divergent milk yield responses to growth restriction-compensation nutritional regimens noted in these studies. Peri et al. (1993) and Johnsson and Obst (1984) fed diets containing 65 and 74 g CP/Mcal ME, respectively, during the growth restriction periods, whereas Barash et al. (1994) fed a diet with only 50 g CP/Mcal ME, suggesting that feeding a lower CP:ME ratio diet during growth restriction may limit mammogenesis. In support of this observation, reported that increased levels of dietary protein stimulated mammogenesis in female rats, and Zhang et al. (1995) found that lambs fed a diet containing 76 g CP/Mcal ME from weaning to puberty had 16% higher ( P < .10) ...
Angus x Holstein heifers (initial age and BW: 6.0 +/- .4 mo; 159 +/- 12 kg) were assigned to one of four treatments (n = 10) in a 2 x 2 factorial arrangement to examine the effects of bovine somatotropin (bST) or vehicle treatment and continuous (CG) or intermittent growth (IG) pattern treatment on mammogenesis. Subcutaneous injections of bST (500 mg) or vehicle were administered at 14-d intervals. The CG heifers were limit-fed a diet to gain .8 kg/d throughout the experiment, whereas IG heifers underwent two successive growth restriction-compensation phases with each phase consisting of a 3-mo growth restriction period (.25 kg/d) followed by a growth compensation period. All heifers were individually fed during the experiment and slaughtered when average treatment BW reached 390 kg. Mammary gland development was measured by dissection, chemical analysis, and computed tomography scanning. Overall ADG were increased (P < .001) 20% by bST treatment of CG heifers, although ADG of IG-vehicle and IG-bST heifers were similar to ADG of CG-vehicle heifers. Dissectable extraparenchymal tissue (EPT) mass was reduced 23% (P < .05) and 36% (P < .001) by IG pattern and bST treatments, respectively, although the bST effect on dissectable EPT tended (P = .08) to be greater in CG than in IG heifers. Fat-free parenchymal tissue (PT) mass (P = .11) and PT volume (P = .08) tended to be greater in IG than in CG heifers. Fat-free PT was 60% greater (P = .01) and PT volume onefold higher (P = .01) in bST than in vehicle heifers. The bST and IG pattern treatments increased the proportional weight of fat-free PT mass, although the effect of bST was greater than IG pattern treatment. There was no evidence to suggest that the two treatments were additive in affecting mammogenesis.
... Data from long-term studies involving four lactation cycles show that stair-step dairy heifers produce 10% more milk compared with conventionally reared control animals ; this increase represents approximately 900 kg of milk over 250 d, while achieving postcalving BW close to control heifers (Park et al., 1989). Others (Barash et al., 1994; Choi et al., 1997; Mantysaari et al., 1999; Peri et al., 1993; Yambayamba and Price, 1997) have also reported an increase in milk yield in first-lactation dairy heifers using a similar dietary regimen. Milk yield is also greater in beef heifers raised on the stair-step regimen than in control heifers (Park et al., 1998). ...
... Nevertheless, high feeding intensity (i.e., overfeeding or unregulated excess plane of nutrition ) imposed continuously during any stage of hormone-dependent mammary development (including prepuberty) is very likely to have adverse effects on not only normal body growth, but also on mammary development and succeeding lactation. Increasing evidence from our laboratory (reviewed in Park, 1998) as well as others (Barash et al., 1994; Choi et al., 1997; Mantysaari et al., 1999; Peri et al., 1993; Yambayamba and Price, 1997) has shown that heifers raised on a well-controlled nutrition regimen (i.e., energy realimentation following a period of energy restriction) during certain hormone-sensitive growth stage(s) can significantly affect mammary development and succeeding lactation potential. While our stair-step nutrition regimen has been proven effective for heifer development and life-long performance, there have been increasing demands by a number of livestock (dairy and beef) producers and animal scientists for a refinement of our stair-step compensatory growth and nutrition program to ease application . ...
The objectives of this study were 1) to examine the interactive influence of a compensatory nutrition regimen and lasalocid supplementation on dairy heifer growth performance and 2) to document the extent to which compensatory growth sustains lactation potential over the first two lactation cycles. Twelve Holstein heifers, weighing an average of 160 kg (about 6 mo of age) were randomly assigned to treatments arranged in a 2 x 2 factorial design. Treatment variables were two dietary regimens (control and stair-step compensatory nutrition) and two levels of lasalocid (0 and 200 mg/d). The control heifers were fed a diet containing 12% crude protein (CP) and 2.35 Mcal of metabolizable energy (ME) per kilogram of dry matter. The stair-step compensatory nutrition heifers were subjected to a phased nutrition regimen and reared according to an alternating 3-2-4-3-4-2-mo schedule. The first stair-step (prepubertal phase) consisted of energy restriction [17% CP and 2.35 Mcal/kg of ME] for 3 mo followed by realimentation (12% CP and 3.05 Mcal/kg of ME) for 2 mo. The second step (puberty and breeding) consisted of energy restriction for 4 mo followed by realimentation for 3 mo. The third step (gestation period) was energy restriction for 4 mo concluding with realimentation for 2 mo. Dry matter intake of heifers during the restriction phase was limited to 70% of the control intake. Heifers were given ad libitum access to a high energy density diet during realimentation to allow compensatory development. Stair-step heifers supplemented with lasalocid had the highest efficiency of growth (body weight gain/dry matter intake), suggesting synergistic metabolism of lasalocid with compensatory growth action. Compensatory growth induced during the last trimester enhanced metabolic status by increasing circulating insulin and decreasing triglyceride levels. Heifers on the stair-step regimen had a significant increase in milk yield during the first (21%) and second (15%) lactation cycles. These results support our thesis that compensatory growth induced during an allometric growth phase improves mammary development and energy and protein metabolic status of dairy heifers.
... This nutrition model was tested using a number of animal species including female rats (3)(4)(5)(6), gilts (7), and heifers (8 -10); most of these works were reviewed (11). Our studies (11) as well as those of others (12)(13)(14) showed consistently that multistep nutrition regimens implemented during peripuberty through gestation enhance mammary growth and lactation performance. However, these multistep models are rather complex and labor intensive. ...
... Multistep nutrition regimens imposed during peripuberty through gestation were shown to positively affect mammary tissue development and subsequent lactation performance (11)(12)(13)(14). However, implementation of these innovative multistep models is rather involved. ...
The proper nutritional status during the hormone-sensitive growth phases preceding first parturition can affect mammary development and subsequent lactation performance. We developed a compensatory nutrition regimen (CNR), which is designed to stimulate mammary growth by exploiting the biological characteristics of the energy restriction and compensatory growth phenomenon. In the present study, we examined the effect of compensatory growth induced only once during late gestation upon mammary development and subsequent lactation potential over 2 lactation cycles. Female rats were mated and randomly assigned to either the control or the CNR group. Control rats were offered the control diet (AIN-93G) throughout the experiment. CNR rats were subjected to 40% energy restriction during the first 10 d of gestation followed by free access to the control diet for the remainder of the experiment. Dams on the CNR produced 14% more milk than control dams (P = 0.12). Mammary cell proliferation rates were approximately 46% (P < 0.05) and 27% (P = 0.07) higher in the CNR group than in the control during late gestation and early lactation of the first lactation cycle, respectively. Caspase-3 enzyme activity was decreased 15% (P < 0.05) and 22% (P = 0.11) in mammary tissues from the CNR group compared with that from the controls during the first and second lactation cycles, respectively. These results indicate that compensatory growth induced only once during late gestation increases mammary cell proliferation and differentiation and decreases regression of mammary cells throughout consecutive lactation cycles.
... Those researchers suggested that during the short compensatory growth in the ad libitum period, they fattened more relative to control heifers. When a 2-step feeding man-agement program was conducted (Barash et al., 1994), puberty of the restricted heifers began during the second ad libitum period, although their BW was 28 kg lower than that of the control heifers. In that same study (Barash et al., 1994 ), it was suggested that the compensatory ration was sufficient to attain the critical body fat content needed to induce puberty, as stated by Smith et al. (1979). ...
... When a 2-step feeding man-agement program was conducted (Barash et al., 1994), puberty of the restricted heifers began during the second ad libitum period, although their BW was 28 kg lower than that of the control heifers. In that same study (Barash et al., 1994 ), it was suggested that the compensatory ration was sufficient to attain the critical body fat content needed to induce puberty, as stated by Smith et al. (1979). Note that all of these reports emphasize the nutritional status of the animal a short time before puberty onset as an important trigger for the process. ...
Forty Israeli-Holstein 5-d-old calves were used to determine the effect of increasing calf body weight (BW) and skeletal size during the nursing period on age and skeletal size at puberty and on skeletal size and performance during first lactation. The calves were randomly allotted to 2 experimental groups as follows: milk replacer (MR) [calves were given 0.450 kg/d dry matter of milk replacer for the first 50 d of life] and milk-fed (MF) [calves had free access to milk in two 30-min meals/d]. From weaning to 180 d of age, all calves were fed the same diet. At 180 d of age, the MR and MF calves were each divided into 2 equal subgroups: one subgroup from each treatment was given only growing ration, and the other was given the same ration supplemented with fish meal to supply 2% crude protein (CP) (treatments MR + CP and MF + CP, respectively). Finally, at 270 d of age, all calves were housed together and fed a growing heifer's ration until first calving. During the entire nursing period, the MF calves consumed 9.8% more DM, 39.7% more CP, and 52.4% more metabolizable energy than the MR calves. At 60 d of age, BW and all skeletal parameters were higher in the MF calves than in the MR calves. During the entire rearing period (60 to 550 d), the average BW of the MF calves was greater by 16 kg than the BW of the MR calves. Nursing management did not affect differences in skeletal parameters at calving. Average age at puberty onset was 272 +/- 26.8 d; MF calves reached puberty 23 d earlier than MR calves. Yields of milk (kg/305 d) and fat-corrected milk (FCM, kg/d) were greater for the MF + CP heifers than for the MR heifers. It was concluded that nursing by ad libitum milk, as compared with milk replacer, affected BW but not skeletal size of the adult animal, decreased age of puberty onset, and increased FCM yield at first lactation. Supplementing the diet with 2% CP during the prepubertal period increased BW but not skeletal size of the adult animal and 305-d milk and FCM yields during first lactation.
... In addition to recovering BW by the end of the study and preventing delayed puberty, the CG treatment was effective in decreasing the DMI in approximately 20% compared with HG heifers. Studies have indicated that heifers subjected to feed restriction after weaning were more nutritionally efficient than heifers gaining BW at constant rates [16,17], without affecting the conception rate [18]. In addition, our results demonstrate that heifers raised on a compensatory growth regimen consumed less feed during the experiment, indicating that compensatory growth may be an effective strategy to reduce costs with the development of replacement heifers, which was also observed by Roberts et al [17]. ...
... Furthermore, adequate skeleton size is needed to minimise dystocia during the first parturition and is more positively related to first lactation milk yield than body weight [87,129]. The majority of skeletal growth occurs during the prepubertal period [60] when rates of withers and hip height growth are as much as 3-fold greater than after puberty [12]. Relative rates of skeletal growth as measured by changes in withers or hip height decrease gradually over time from as much as 5 cm/month at 2 months of age to around 1 cm/month during the post-pubertal period [60]. ...
... The body condition of the grazing animal is at its best during this period, but with the onset of the dry season both quantity and quality of the pasture herbage decline and fail to support any performance demand. In fact, in most cases cattle catabolise body reserves and loose body weight during this period to meet maintenance requirement, but compensate body weight during the next rainy season (Ryan 1990 andBarash et al 1994). However, with a market oriented dairy production system opportunities for investing in active forage production and conservation methods can be an option. ...
This study aims at understanding the cattle production system and production constraints and identifying cattle breeding goals of breeders in Butana and Kenana cattle areas in central Sudan as the first step towards developing a sustainable breed improvement programme. A set of detailed structured questionnaires were used to collect information from Butana and Kenana cattle owners in one-visit-interviews. Butana and Kenana cattle are kept in a mixed crop-livestock production system and are the dominant livestock species. The majority of Butana cattle owners indicated livestock to be their main activity while for the majority of Kenana owners both livestock and crop farming are important activities. Cattle have multi-functional roles in both production systems. Milk production is important for obtaining regular cash income and home-consumption needs. The unfavorable production conditions determine the rather low milk yield of Butana and Kenana herds in their habitats. Measures overcoming production constraints are given clear priority by cattle owners. However, the realization options are insecure unless a stronger market orientation can be developed. Breeding policies targeting Butana and Kenana cattle smallholder need to incorporate the multi-functional roles of cattle in these systems and should be focused to those areas where market oriented milk production is possible.
... Grasses grow rapidly during the short wet season producing abundant biomass, and the body condition of cattle improves. In the dry season both quantity and quality of the pasture decline, and cattle lose body weight and compensate the loss during the next rainy season (Ryan 1990 and Barash et al., 1994). Although the two ecotypes are phenotypically distinct they are similar in productivity and adaptability to harsh environments. ...
One hundred one dairy small holders, of both Kenana and Butana cattle in nine villages in the homeland of Kenana and Butana cattle in Sudan were randomly selected, with the objective of characterizing dairy production systems, adopted management practices, breeding objectives and constraints, for dairy development in this area. The average age of household heads in study was 54.92±7.78 and 56.73±12.0 years for Kenana and Butana, respectively. With regard to educational status, the proportion of Khalwa (Quranic schools) was high among both Kenana (56%) and Butana (62.7%) herders. The average herd size of Kenana and Butana cattle was 10 and 6 animals, respectively. Sale of milk was the main source of income in Kenana area (100%) while it was up to 50% of the total income in Butana area. Forty eight percent of Kenana herders bred their cow to their own bulls, while most Butana owners relied bulls from other sources such as neighbors. The criteria for selection of breeding bulls were body conformation (72%) and (80.4%) for Kenana and Butana owners, respectively. The disease reported most by Kenana owners was Trypanosomosis (61.8%), while tick problems was the major concern among Butana herders. Constraints for dairy development in Kenana area included, poor pastures. Unavailability and high costs of feeds and shortage of water predators, disease, poor animal health and extension services were the major constraints in the Butana region. Dairying in the studied area can be improved through the provision of services related to feed supply, use of non-conventional feed resources, improving access to water, allocating land for semi intensive farms. A sustainable genetic improvement program and the provision of veterinary and extension services are also central to development.
... Although rate of gain is important for heifers to reach puberty at an early age, rapid growth during the prepubertal period can decrease subsequent milk production (Mangus and Brinks, 1971;Kress and Burfening, 1972;Holloway and Totusek, 1973;Beltran, 1978;Martin et al., 1981;Sejrsen et al.,1982;Harrison et al., 1983;Johnsson and Obst, 1984;Laflamme, 1993;Sejrsen, 1994;Sejrsen and Purup, 1997). Stair-step nutritional management regimens were used to limit growth during critical periods of mammary development and to subsequently allow periods of rapid growth to permit heifers to reach puberty at an early age ( Park et al., 1989Park et al., , 1998Barash et al., 1994;Choi et al., 1997;Lynch et al., 1997). Grings et al. (1998Grings et al. ( , 1999) reported little direct effect of either trace mineral supplementation or altering rates of gain from weaning through the beginning of the breeding season on reproductive performance and subsequent milk yield for beef heifers gaining over .6 kg/d. ...
Selection and management of replacement beef heifers involve decisions that affect future productivity of an entire cowherd. The decision to breed heifers as yearlings involves careful consideration of the economics of production and the reproductive status, breed type, or genetic make-up of the heifers involved. Reproductive competence is established as a consequence of a specific program of developmental events leading to organization of functionally competent reproductive tissues and organs. The timing of puberty is critical in determining whether a heifer remains in the herd and the extent to which lifetime productivity is achieved. Because most components of fertility that influence calving and subsequent reproductive performance are not highly heritable, it is logical to assume that the majority of factors related to reproductive performance in cattle are influenced almost entirely by management. Utilization of various prebreeding management technologies enables producers to improve breeding performance of heifers during the first breeding season and during the subsequent calving and rebreeding period as 2-yr-olds. These practices help to ensure that heifers entering the herd as raised or purchased replacements will contribute to the general performance and productivity of an entire cowherd immediately, and cumulatively long-term. This review examines the relative merits of these various practices and provides an assessment of the adoption rate of specific reproductive management proce-dures for replacement beef heifers.
... In the studies of Park et al. (1998) and Choi et al. (1997) use of stairstep feeding where restricted and ad libitum feeding regimens were alternated, increased milk production by 6 and 9%, respectively. However, Barash et al. (1994) observed no effect on milk production when six-months old heifers were fed 4 months with low-energy diet followed by 2 months with a high-energy and high-protein diet that led to compensatory growth. ...
Mäntysaari, P. 2001.Effect of feeding before puberty and during gestation on milk production potential andbody development of dairy replacement heifers. University of Helsinki, Department ofAnimal Science. Publications 60. 44p. + 5 encl.
ABSTRACT
This thesis consists of studies concerning the effect of feeding before puberty and duringgestation on pre-pubertal mammary growth, subsequent milk yield and body development ofreplacement heifers. Publications I and II investigated the effect of high (daily gain 850 g) orlow (daily gain 650 g) levels of feeding with urea or rapeseed meal as protein supplements ongrowth and mammary development of pre-pubertal Finnish Ayrshire heifers. It was shownthat heifers on the high feeding level had less mammary parenchymal tissue compared withheifers fed lower levels of feeding. The amount of mammary parenchymal tissue waspositively correlated with plasma growth hormone (GH), but not plasma IGF-Iconcentrations. Furthermore, no correlation existed between plasma GH and IGF-Iconcentrations. On a high feeding level Finnish Ayrshire heifers under 220 kg live weight hada higher growth rate when rapeseed meal rather than urea was used as protein supplement ona hay-barley based diet. For pre-pubertal slaughter heifers it appears that urea is not suitablesource of supplementary nitrogen for hay and barley based diets. Instead, protein source hadno effect on pre-pubertal mammogenesis at either feeding level.The effect of feeding intensity during gestation on subsequent milk yield was investigated inpublication IV. It was shown that during the first six months of gestation daily gains of 800 g,or higher, had no effect on subsequent milk yield but resulted in greater fat deposition andreduced postpartum intake potential. On the other hand, during the last trimester a high levelof feeding (live weight change over 800 g/d) was advantageous in attaining maximal milkproduction.The effect of feeding on body development of pre-pubertal (publications I and III) andpregnant heifers (publication IV) was examined. It was observed that pre-pubertal heifers fedon a low level of feeding had higher wither heights at puberty than heifers fed moreintensively. Results suggest that pre-pubertal wither height is determined more by age thanlive weight. Heart girth was shown to be a good predictor of pre-pubertal live weight. Duringpregnancy high (gain 800 g/d) compared with moderate (gain 650 g/d) planes of nutrition hadno effect on body size (wither height, body length) but increased heart girth, hip width andbody condition score of primiparous cows at parturition.Live weight at parturition and daily gain before and after breeding had positive geneticcorrelations with first lactation milk yield within field data reported in publication V.Therefore, it appears that genetic selection for higher milk production will gradually lead tohigher genetic growth potential. Such changes need to be taken into account in futurerecommendations of daily gain acceptable for pre-pubertal dairy replacement heifers.Based on the current studies it was suggested that for pre-pubertal Finnish Ayrshire heifersdaily gains above 650 to 700 g have detrimental effects on pre-pubertal mammogenesis.Dietary protein source has no effect on mammary growth. During the first six months ofgestation a moderate feeding level is recommended to avoid excessive fat deposition andensure maximal postpartum intake. However, during the last trimester intensive feeding isnecessary in attaining maximal milk production.
Effect of feeding before puberty and during gestation on milk production potential and body development of dairy replacement heifers. Available from: https://www.researchgate.net/publication/47932245_Effect_of_feeding_before_puberty_and_during_gestation_on_milk_production_potential_and_body_development_of_dairy_replacement_heifers [accessed Mar 02 2018].
... Compensatory gains have been reported in heifers fed a high energy-dense diet after an initial period of less energy-dense diet (Barash et al., 1994). ...
This 3-yr study used 490 steers to determine whether feedlot steers changed their feed efficiency (FE) ranking when fed a grower diet, then a finisher diet. The steers were crossbreds and were between 5 to 7 mo of age. There were 2 feeding periods each year. Within each year, approximately 90 steers had their diet switched from a grower to a finisher diet (feed-swap group), whereas another 90 steers were fed either the grower (grower-fed group) or the finisher (finisher-fed group) diet throughout the feeding trial. Each feeding test lasted for a minimum of 10 wk, and all steers were fed ad libitum. Individual animal feed intakes were collected using the GrowSafe feeding system, and BW were measured every 2 wk. Residual feed intake (RFI), G:F, and Kleiber ratio (KR) were computed at the end of each feeding period. For each measure of efficiency, animals were classified as low, medium, or high based on 0.5 SD from the mean. The majority of steers did not maintain the previous efficiency class in the second period. Approximately 58, 51, and 51% of steers in the feed-swap group, finisher-fed group, and the grower-fed group, respectively, changed their RFI measure by 0.5 SD. A low rank correlation occurred in all test groups but was less in the feed-swap group. Spearman rank correlations between the 2 feeding periods in the feed-swap group were 0.33, 0.20, and 0.31 for RFI, G:F, and KR, respectively. Classifications based on G:F and KR showed that a greater number of steers (P < 0.05) in the feed-swap group did not maintain their FE class from 1 feeding regimen to the other, whereas classification based on RFI did not show any difference (P > 0.05) between the proportions of individuals that changed or maintained their FE class. In the groups without a feed-swap, there was no difference (P > 0.05) in the proportion of steers that changed or maintained the same FE class for all FE measures. Our results suggest that diet type and feeding period affect the FE ranking in beef steers. A feedlot diet is ideal for evaluating the FE potential of steers for feedlot profitability; however, we suggest that tests involving less dense diets should be examined in an effort to understand the relationships between FE and feeder profitability.
... Little and Kay (1979) and Macdonald et al. (2005) reported long-term effect of accelerated growth rate during the prepuberty period on BW at the subsequent lactation. In another study, Barash et al. (1994) demonstrated a similar pattern, where Holstein bulls that were assigned to restricted nutrition followed by realimentation period failed to reach the BW of bulls fed conventional management. In contrast to BW, HH and HW were higher in the WM heifers than in the MR heifers during the prepubertal period. ...
Our objectives were to determine the effects of rapid growth rate during the preweaning period and prepubertal protein supplementation on long-term growth pattern and milk production during the first lactation. Forty-six Israeli Holstein heifer calves were fed either milk replacer (MR) or whole milk (WM) from 4 to 60 d age. Calves had free access to WM or MR for 30 min twice daily and free-choice water and starter mix for the entire day. From weaning until 150 d of age, all heifers were fed the same ration. At 150 d of age the heifers were divided into 2 subgroups, with one subgroup supplemented with an additional 2% protein until 320 d of age. Thereafter, all heifers were housed and fed together until calving. Another cluster of 20 heifers was raised on MR and WM treatments and 3 animals from each nursery treatment were slaughtered at 60 d and 10 mo age to determine effects of nursery treatment on organ and adipose tissue mass. Prior to weaning, the MR heifers consumed 0.12 kg/d more DM than the WM heifers, but metabolizable energy intake was not different. Body weight at weaning and average daily gain during the preweaning period were 3.1 kg and 0.074 kg/d higher, respectively, in the WM treatment than in the MR treatment, with no differences in other measurements. Nursery feeding treatment and added protein had no effect on growth rate in the prepubertal period, but the postweaning difference in BW between the WM and MR heifers remained throughout the entire rearing period. The age at first insemination was 23 d earlier and age at pregnancy and first calving was numerically lower for the WM heifers than for the MR heifers. Adipose tissue weights at weaning were doubled in the WM calves. First-lactation milk production and 4% fat-corrected milk were 10.3 and 7.1% higher, respectively, for WM heifers than for MR heifers, whereas prepubertal added protein tended to increase milk yield. In conclusion, preweaning WM at high feeding rates appears to have long-term effects that are beneficial to future milk production. The positive long-term effects of feeding WM on first-lactation milk production were independent of their effects on skeletal growth. Enhanced milk production observed with WM treatment may be related to the milk supply, paracrine or endocrine effects of fat tissues on mammary parenchyma, or a combination of both factors.
... Even though rate of gain is important for heifers to reach puberty at an early age, rapid growth during some phases of prepuberal development can decrease subsequent milk production (Sejrsen et al., 1982;Harrison et al., 1983;Sejrsen, 1994;Sejrsen and Purup, 1997). Stair-step nutritional management regimens have been used to limit growth during critical periods of mammary development and then to allow periods of rapid growth to permit heifers to reach puberty at an early age (Park et al., 1989(Park et al., , 1998; Barash et al., 1994;Choi et al., 1997;Lynch et al., 1997). ...
A study was conducted to evaluate the influence of nutrition and sire breed on age at puberty and first lactation milk yield in crossbred beef heifers. After weaning, 208 heifers sired by Hereford, Limousin, or Piedmontese bulls were assigned to either a control (CG) or stair-step gain (SSG) dietary regimen plus a mineral supplement with or without Cu, Zn, and Mn top-dressed onto the feed. Heifers on the SSG regimen were fed a diet intended to supply energy to support gains at a rate of 120% of the CG diet for 55 d and then were switched to a diet formulated to produce an ADG at 70% of the rate of the CG diet for 84 d. They then switched back to the 120% diet for the last 30 d before breeding. Total weight gain and overall rate of gain did not differ among dietary treatments. Hereford- and Limousin-sired heifers gained at similar rates, and Piedmontese-sired heifers gained an average of .10 kg/d slower than the other two sire breed groups. During one period, Piedmontese-sired heifers on the CG diet gained .19 kg/d faster ( P < . 01) when supplemented with mineral than when not. During that same period, there was no influence of mineral supplementation on weight gains for Hereford- or Piedmontese-sired heifers on the high SSG diet, but Limousin-sired heifers tended (P = .07) to gain faster (1.00 vs .85 kg/d) when supplemented with Cu, Zn, and Mn than when not. Piedmontese-sired heifers reached puberty at the earliest age (P = .03), followed by Hereford- and then Limousin-sired heifers. There were no treatment effects on milk yield at an average of 70 d of lactation. However, at approximately 120 d of lactation, Piedmontese-sired heifers were producing less milk (P < .05) than Limousin- but not Hereford-sired heifers. Hereford-sired heifers had lower (P < .05) plasma Cu concentrations than Piedmontese-sired heifers. There were no treatment effects on plasma Zn concentrations. Heifers sired by bulls of breeds that differ in potential muscularity differed in growth, reproduction, milk yield, and plasma mineral concentrations, but dietary treatments resulted in little to no differences in these variables.
... This nutrition regimen is a combination of both energy restriction and realimentation that allows minimal development of mammary tissues during an energy restriction phase, whereas a compensatory growth phase immediately after energy restriction stimulates rapid and fuller development of the mammary gland. Our studies (reviewed in Park 1998) as well as those of others (Barash et al. 1994, Choi et al. 1997 have shown that a well-controlled compensatory nutrition regimen imposed during hormone-sensitive growth stages before first parturition can significantly affect mammary development and lactation performance. ...
A nutritionally-regulated compensatory growth regimen imposed during a growing period from prepuberty to gestation can significantly affect mammary development and subsequent lactation performance. The objectives of this study were as follows: 1) to determine whether a compensatory nutrition regimen enhances lactation potential for the first and second lactation cycles and 2) to determine the extent to which a compensatory nutrition regimen modulates cell proliferation, differentiation, and apoptosis and expression of genes in mammary tissues of female rats. Female Sprague-Dawley rats (n = 122, 35 d of age) were randomly assigned either to the control group, with free access to diet, or to a stair-step compensatory nutrition feeding regimen, with an alternating 2-2-3-3-wk schedule. The regimen began with an energy-restricted diet (40% restriction) for 2 wk, followed by the control diet for 2 wk; this step was then repeated at 3-wk intervals. Pups of dams from the compensatory nutrition regimen group gained more during mid-lactation than did control group pups. Mammary tissues were obtained from early (d 2) and late (d 19) lactating rats. Mammary tissue from the compensatory nutrition group exhibited increased cell proliferation and greater gamma-glutamyltranspeptidase and ornithine decarboxylase gene expressions than did tissue from the control group during early lactation of both cycles. Mammary tissue from the compensatory nutrition group also had fewer apoptotic cells than tissue from the control group during late lactation of the first lactation cycle. These results suggest that the compensatory nutrition regimen imposed during the peripubertal developmental phase stimulated mammary growth and enhanced lactation performance by affecting the expression of genes that regulate the cell cycle.
... These results were similar to those of Sieber et al. (1988), where again withers height was a more important factor than BW in relation to firstlactation milk yield. The majority of skeletal growth occurs during the prepubertal period (Heinrichs and Hargrove, 1987), when rates of withers and hip height growth are as much as 3-fold greater than after puberty (Barash et al., 1994aBarash et al., , 1994b). Relative rates of skeletal growth as measured by changes in withers or hip height decrease gradually over time from as much as 5 cm/mo at 2 mo of age to around 1 cm/mo during the postpubertal period (Heinrichs and Hargrove, 1987). ...
The objectives of this study were to determine the effect of recombinant bovine somatotropin (bST) and added dietary rumen undegradable protein (RUP) on organ and tissue weights and body composition in growing dairy heifers. Thirty-two Holstein heifers were in the experiment, 8 killed initially at 3 mo of age, with the remaining 24 Holstein heifers randomly assigned to treatments (n = 6) consisting of 0.1 mg/kg of body weight per day of bST and 2% added dietary RUP (dry matter basis) applied in a 2 x2 factorial design. A total of 6 heifers per treatment group (3 each at 5 and 10 mo of age), were slaughtered to determine body composition and organ masses. Feed intake measured from group intakes were increased by 0.25 and 0.35 kg/d with bST and RUP, respectively. Administration of bST tended to increase the weights of visceral organs including heart, kidney, and spleen by 16, 16, and 38%, respectively. At 10 mo of age, there was a trend for increased empty body weights (EBW) and non-carcass components for heifers treated with bST, but there were no effects of RUP. Body components and organ weights, expressed as a percentage of BW were not affected by RUP or bST. Somatotropin increased ash weight at 10 mo without affecting amounts of protein, fat, and energy. Rates of ash deposition between 3 and 10 mo of age were increased 7 and 4 g/d by bST and RUP, respectively. There were no treatment effects on rates of body fat, protein, and energy deposition. Bovine somatotropin and RUP altered the metabolism of growing heifers in a manner that was consistent with increased rates of skeletal growth. This suggests that nutritional and endocrine manipulations could increase growth rates of skeletal tissues without increasing fat deposition in prepubertal dairy heifers.
Lactational and reproductive performance are strongly associated with cow live weight and capacity. However, there are limited data published describing capacity (thoracic) growth and the prediction of final stature and capacity from measurements at birth. Therefore, the aim of this study was to examine the relationship between stature and live weight of female dairy cattle between birth and maturity. Forty dairy cows, with records of stature and capacity from birth up until two years of age, underwent follow-up measurements for live weight, height at withers, wither-rump length, girth circumference and leg length on four occasions between 42 and 52 months of age. Measures of wither height, leg length and wither rump length at fourth mating had the strongest association with measures at birth (R2 > 0.90) compared to girth and live weight (R2 = 0.88 and 0.82, respectively). The weaker association between birth and maturity measures for girth is likely a reflection of the stronger relationship with live weight resulting in a later maturity (approximately 810 days) compared to linear measures such as height (approximately 730 days). Therefore, to maximise capacity, adequate nutrition is required until approximately 810 days of age when capacity growth is most sensitive to environmental input.
Eighteen prepubertal Israeli-Holstein heifers were used in an experiment to study the effects of protein supplementation and implantation of Synovex-C on body weight gain (BWG), skeletal size and age at puberty. Heifers were allocated to three treatment groups as follows: 1. heifers received a diet that was formulated according to NRC (1989; Control) recommendations, 2. heifers received the same diet fed to heifers on treatment 1 except that the diet was supplemented with 3.3% maize gluten meal (MGM) during the first 6 months and with 2.5% MGM during the next 3 months 3. heifers received the same diet fed to heifers on treatment 2 and were implanted with Synovex-C. Supplementation of MGM to the diet enhanced BWG during the first 183 d of the experiment. The implantation of Synovex-C enhanced BWG only during the first 92 d of the experiment. From d 93 to 281, BWG of heifers on treatment 3 was reduced, and, by the end of the experiment, the BW of these heifers tended to be lower than of heifers on treatment 2. Supplementation of MGM to the diet enhanced growth rates of the wither and hip during the first 281 of the experiment. However, implantation of Synovex-C eliminated the effect of supplemented MGM, and, towards the end of the experiment, withers and hip heights of heifers on treatment 3 were lower than those of heifers on treatment 1. Implantation of Synovex-C was associated with increased serum IGF-1 during the first 150 d of the experiment and with reduced age and wither height at puberty.
Twenty-one 6-month-old Israeli Holstein heifers were used to determine the effect of three 6-month feeding regimes on growth, blood concentration of insulin, prolactin and insulin-like growth factor-1 (IGF-1), attainment of puberty and milk production during first lactation. Feeding regimes were as follows. (1) Restricted: the heifers were given food during months 1, 2 and 4, 5 of an experimental period, to support live-weight (LW) gain of 0·35 and 0·50 kg/day, respectively and during months 3 and 6 the heifers were given food to support compensatory growth. (2) Control: the heifers were given food to support LW gain of 1·0 kg/day. (3) Control + C: the heifers were given the same as the control, with a daily supplement of 0·05 mg/kg LW cimaterol (C) for 4 months. The total LW gain of the restricted heifers during the 6 months of the trial was significantly lower than that of the control heifers. Cimaterol improved growth rate only during the first 2 months of its application and its withdrawal was associated with severe LW gain retardation. The feeding regime employed in the restricted treatment was associated with a significant reduction in serum concentrations of insulin, prolactin and IGF-1 during the first restricted phase, followed by an elevation in the first compensatory phase. During the second restriction-compensation cycle, only the serum concentration of prolactin was significantly reduced. Cimaterol addition was also associated with a reduced blood concentration of the hormones. The animals in the restricted, control and control + C groups attained puberty at LW of 249·2, 277·6 and 304·9 kg (P <0·05), respectively. No effect of the treatments on milk yield was observed. The effect of the feeding regimes on skeletal growth and on metubolizable energy efficiency for growth is discussed.
In this review, I have been asked to provide insight into the structure and related function of the chorioallantoic placentae
of different livestock species, with emphasis on their role in mediating conceptus growth and survival. As there have been
many excellent books and reviews written on comparative placentation, I have decided to focus this paper on a comparison of
two livestock species with which I have a long research history, namely the pig and the sheep, but will present comparisons
with other species where appropriate and warranted. Further, I will stress the importance of placental vascularity and blood
flow in dictating normal growth, development and survival of the fetus. Throughout my research career, I have conducted studies
aimed at gaining a better understanding of conceptus-uterine interactions, in an attempt to understand how intrauterine and
extrauterine events impact the conceptus. Significant data have accumulated suggesting that negative impacts on the fetus,
occurring during critical periods of gestation, result in developmental adaptations that can permanently change the growth,
physiology and metabolism of offspring [3, 28, 41, 49].
The vast majority of mammary growth occurs postnatally. For example, in dairy cows mammary parenchymal mass increases approximately
10,000-fold, from less than 0.5g per gland at birth to approximately 5.5kg during lactation, and the mammary epithelium
differentiates from a primitive branching ductal network to a fully differentiated lobuloalveolar network that is capable
of synthesising copious quantities of milk. These growth and developmental processes are hormonally regulated, but also involve
extensive interactions among cell types (e.g. stromal, epithelial, myoepithelial, stem and progenitor cells) and local regulation
by paracrine/autocrine factors. Appropriate nutrient intake and balance is important for mammary growth and development, and
these processes may be influenced by under- or over-nutrition. Because of interactions between the environment and the endocrine
system, mammary development and differentiation can be influenced by additional factors such as bioactive substances in feed
and by photoperiod. Ultimately, milk yield is determined by the number of fully differentiated mammary epithelial cells and
by homeorhetic mechanisms that regulate functions of other organs to support milk production.
The productivity of the pig ranks high when compared with the other classes of farm mammals. Reproductive potential is the
most important factor contributing to total meat production from this species. The high rate of productivity in the pig is
dependent upon early sexual maturity, a comparatively high ovulation rate, relatively short periods of gestation and lactation,
as well as the capability of repeating the pregnancy cycle soon after weaning a litter. Some important limitations affecting
this production potential are ovulation rate, embryonic death, and perinatal and neonatal losses. This review focuses on (1)
the roles of maternal nutrition and ovarian function on fetal development, (2) genotype of the dam affecting fetal development
and litter size, (3) maternal circulating hormone concentrations during different stages of gestation as related to fetal
development and litter size, (4) effects of specific nutrients and hormones for the dam on fetal development, and (5) maternal
reproductive diseases affecting fetal development.
More than 50 years ago, it was noted that wool follicle development in sheep fetuses suffering growth restriction in utero
(e.g. twin lambs or single lambs born to maiden ewes) was significantly impaired [105]. A little later, observations of the
postnatal wool production performance in lambs from ewes undernourished during gestation indicated that restriction of fetal
development had permanent effects upon wool follicle development and long-lasting effects upon postnatal wool fibre production
[107]. Though not described in this way at the time, these were early indicators that programming of the fetus for development
takes cues from the “maternal environment” during gestation. The cues can be in operation as early as the first few days in
embryonic life and possibly earlier [69, 120]. Fetal programming, and influences on gene expression and ultimately development
imposed upon the fetus in utero, has become a topic of increasing interest over the last decade. This is especially so since
lifetime consequences of such programming have been demonstrated in humans [6, 73]. Perturbed fetal programming can occur
through different mechanisms and the effects of one such mechanism, intra-uterine growth retardation (IUGR), on development
of the progeny have been reported in many publications.
In recent decades, the rate of weight gain of meat-type broiler chickens has increased significantly [25, 26]. In the 1960s,
a commercial broiler chicken reached the market weight of 2.2kg by 12 weeks of age; today, broilers attain this same market
weight at less than 6 weeks. This impressive improvement is due to the knowledge accumulated by industry poultry managers
and researchers from different disciplines – geneticists, nutritionists, physiologists and veterinarians – who have contributed
to the optimisation of broiler performance.
There has been a recent explosion in research on consequences of fetal development for postnatal health in humans, and in
the use of the sheep as a model to understand postnatal consequences of altering the prenatal environment (for review see
[87]). However, there is an important need for a review that quantifies consequences of prenatal nutrition for postnatal productivity
in ruminants, particularly on the extent to which traits of economic importance can be influenced or programmed by variations
in the maternal and fetal environment within production systems.
Pigs are a litter bearing species that give birth to an average between 9 and 13 pigs per litter depending on breed and country.
The gestation length is 113–115 days. Early gestation ends at around day 40, and mid gestation at about day 80. In conventional,
indoor pig production the lactation period is 3–4 weeks, thus pigs are weaned at around days 21–28at a mean live body weight
of between 6 and 8kg. In most countries, pigs are slaughtered when they reach a live body weight between 90 and 120kg, although
production of heavier pigs is common in some counties.
Over recent years there has been a lot of interest in the effects of prenatal environment on subsequent development of tissues
and the postnatal consequences. In farm animal species this has particularly related to muscle and fat development and the
later consequences in terms of body composition at slaughter. Studies have been carried out in a variety of species, including
rats, guinea pigs, pigs, sheep and, more recently, cattle. This chapter will concentrate on the evidence for effects of prenatal
environment on development of muscle and adipose cells in ruminant species, the possible mechanisms for these effects and
the long-term consequences relating to postnatal growth and body composition.
The phenotype of a newborn piglet is the result of its embryonic and fetal development, which is a very complex and highly integrated process. Fetal growth retardation results in low birth weight, which has detrimental consequences for the piglets' vitality, postnatal growth rate as well as carcass and meat quality [3, 38, 164]. Therefore, understanding mechanisms that control fetal growth are essential to develop successful strategies to reduce the incidence of fetal growth retardation. Copyright © International Atomic Energy Agency 2010. All Rights Reserved.
Holstein bull calves at 138.4 d of age were fed one of four diets that contained 2.28, 2.43, 2.61, or 2.8 Mcal of metabolizable energy/kg of dry matter and 10.8, 11.7, 12.8, or 13.9% crude protein, respectively, for 77 d followed by a diet that contained 2.80 Mcal of metabolizable energy/kg of dry matter and 13.9% CP. During the energy restriction period, the metabolizable energy of the diets was positively correlated with the plasma concentration of insulin-like growth factor-I, which was positively correlated with daily body weight (BW) gain during this period and the plasma concentration of total thyroxin. During the first 37 d of the realimentation period, compensatory growth occurred, and the rate of increase in plasma concentrations of insulin-like growth factor-I was positively correlated with that of daily BW gain. At d 37 of the compensatory period, the mean plasma concentration of total thyroxin in calves in three of the four groups did not differ significantly; only the concentration of total thyroxin in the plasma of calves fed the highest energy restricted diet was significantly higher. The mean BW of calves in groups fed the high energy diets during the restriction period tended to be heavier even after 158 d of the realimentation period.
During the several decades that hormones have been considered for roles in the control of feeding, certain ones have gained special attention, although the role assigned to any one hormone has varied from time to time. Three classes of hormones have been considered in this review: gastrointestinal, brain, and pancreatic. Of these classes, two have obtained the most compelling evidence for a physiological role in the control of feeding. CCK, an intestinal and brain hormone, appears to be involved in satiety. Glucagon of pancreatic origin appears also to play an important role in satiety. These hormones, when sequestered by a specific antibody, cause a delay in satiety and thus increase food intake. Insulin, another pancreatic hormone, has been considered for several roles in the control of feeding. Recently, attention has been given to the possibility that insulin of the CSF provides an integrated link between the metabolic state of the adipose tissue and the brain structures concerned with the control of feeding. Thus, insulin may be a primary hormone involved in the maintenance of energy balance or of body-weight. Finally, brain opiate peptides, e.g. dynorphin, are very likely involved in the transmission of information concerned with the interaction of feeding and maintenance of energy balance. Clearly, hormones play primary roles in the control of feeding behaviour and the regulation of energy balance, but much remains to be done to establish their specific actions or components of the associated physiological systems.
Effects of fiber vs starch energy supplements on endogenous growth hormone (GH), insulin-like growth factor (IGF-1) and animal performance from weaning to breeding age were evaluated in 18, 9-mo-old beef heifers. Heifers had ad libitum access to wheat silage plus an average daily supplement intake of 1) 4.08 kg corn-soybean meal (SBM) (high energy-starch, HS), 2) 4.54 kg soyhulls (SH)-SBM (high energy-fiber, HF) or 3) 1.36 kg SH-SBM (low energy-fiber, LE). Serum samples were collected via jugular puncture every 10 d and were analyzed for IGF-1 by RIA. On d 45 and d 176, four heifers per treatment were fasted 18 h and serial blood samples collected via jugular cannulas every 15 min for 6.5 h. Arginine (.5 g/kg BW) was administered intravenously (ARG) to induce release of GH, and four additional samples of blood were collected. Samples were analyzed by RIA for GH. Mean fasted GH (6.4 +/- .4, 8.3 +/- .4 and 13.8 +/- .4 ng/ml for HS, HF and LE, respectively) varied with energy source and level (P less than .01). Mean GH following ARG was higher (P less than .01) in heifers receiving LE (46.2 +/- 4.7) than in those receiving HS and HF (23.5 +/- 4.4 and 24.1 +/- 4.6 ng/ml). Basal GH concentration and peak amplitude were higher (P less than .05) in LE than in HS and HF treatments. Diet did not influence number or frequency of GH peaks.(ABSTRACT TRUNCATED AT 250 WORDS)
The primary objective of this study was to improve the productive efficiency of growth via optimal use of both high fiber-low quality and high energy-high protein feeds in diets for growing dairy cattle. Twenty Holstein heifers were randomly assigned to either a control or treatment group. The control diet met the National Research Council (NRC) requirement for .45 kg/d gain, with heifers calving at 24 to 26 mo of age. The test groups were fed according to a 5-2-5-2 mo schedule in which the nutrient density was alternately 15% below or 40% above the NRC requirement. Results showed that the heifers on the test dietary regimen (compensatory growth) gained more and consumed less, resulting in significantly improved efficiency of growth (body gain/dry matter intake X 100), energy (body gain X 1,000/metabolizable energy (ME) intake) and protein utilization (body gain/protein intake X 100) in comparison to control animals (13.0 vs 7.3%; 57.9 vs 32.6 g/Mcal ME; 96.5 vs 54.2%, respectively). Marked changes in average concentration of urea-N, glucose, triglycerides, cholesterol and lecithin cholesterol acyltransferase activity in blood were seen for test heifers during the stair-step growth phase (i.e., alternating maintenance and compensatory). Evidence from this experiment suggests that the phased growth (stair-step) system offers a simple, practical and cost-effective method for raising dairy heifers.
Twenty prepubertal heifers (averaging 155 kg body weight) were assigned to one of four treatment groups in an experiment of 2 X 2 factorial design. The main effects were photoperiods of 8 h light:16 h dark (8L:16D) vs 16L:8D, and LOW vs HIGH plane of nutrition. Heifers on the LOW plane of nutrition were fed to achieve a growth rate of approximately .7 kg/d; daily feed intake was restricted with no orts and was identical in both groups of heifers subjected to either 8 or 16 h of light daily. Heifers on the HIGH plane of nutrition were fed ad libitum to achieve a growth rate greater than 1 kg/d. All heifers were slaughtered during the luteal phase of an estrous cycle at an average body weight of 337, 334, 360 and 349 kg for 8L:16D-LOW plane, 16L:8D-LOW plane, 8L:16D-HIGH plane and 16L:8D-HIGH plane groups, respectively. Average time on treatment was 233, 236, 206 and 181 d and average estimated carcass weight gain was .39, .40, .55 and .61 kg/d, respectively. Within LOW or HIGH planes of nutrition, photoperiod did not affect live body weight gains. A photoperiod of 16L:8D, compared with 8L:16D, increased protein content in the 9-10-11th rib section of heifers on HIGH nutrition (16.2 vs 14.6%), but not in heifers fed the LOW plane of nutrition (15.5 vs 16.1%). However, within 8L:16D groups, HIGH plane reduced rib section protein content as compared with LOW plane of nutrition (14.6 vs 16.1%); there was no difference observed within 16L:8D groups.(ABSTRACT TRUNCATED AT 250 WORDS)
Twenty-seven multiparous Holstein cows averaging 120.7 DIM, 9 per diet, were assigned at random to 20, 17, or 14% ADF diets of corn, corn silage, and soybean meal, following a covariant period when all cows received the 14% ADF diet. An 18-d period (period 1) of cool weather preceded the onset of high environmental temperature from June 1988 to the end of July 1988 (period 2). Mean daily maximum air temperatures were 35.2, 36.8, and 34.7 degrees C for the covariant period and for periods 1 and 2, respectively. Minimum temperatures were 14.5, 16.0, and 21.5 degrees C. Milk production during both periods was higher, and the decrease in milk production associated with the onset of hot weather was lower, in cows fed the 14% ADF diet. Intake was not affected by diet during period 1 but was lower in cows fed the 17 and 14% ADF diets in period 2 relative to period 1. At any given environmental temperature, DMI was higher in cows fed lower ADF diets. Although DMI declined more rapidly with increasing daily minimum temperature with lower ADF diets, milk production was less sensitive to daily minimum temperature in cows fed the 14% ADF diet.
The parenchymal portion of the mammary gland is immature at birth and begins to grow at a faster rate than the whole body shortly before occurrence of puberty. This accelerated or allometric growth rate is maintained for several estrous cycles, then returns to a growth rate equal to general body growth. Allometric growth of the mammary gland returns at conception and continues in most species for a variable period after parturition. Elevated secretion of estradiol and progesterone throughout pregnancy drives the allometric mammary growth during pregnancy. However, mammary growth during lactation in cows is independent of ovarian secretions and prolactin. Mammary cell numbers during lactation eventually decline as milk production decreases. Concurrent pregnancy reduces mammary cell numbers during lactation, but during the dry period concurrent pregnancy markedly increases mammary cell numbers over those in nonpregnant animals. Dry periods that are short reduce the increments in mammary cell numbers, which normally occur during early stages of the next lactation. Because numbers of mammary epithelial cells are a major determinant of milk yield, understanding the mechanisms that stimulate mammary epithelial cell numbers has the potential to lead to new methods for increasing efficiency of milk production.
Two trials involving 280 Holstein heifer calves were to determine effects of increasing nutrient intake on growth (weight, height, and heart girth), dry matter intake, and water intake. In trial 1, 80 calves were fed from 60 to 172 d of age. More calf grower fed increased daily gain from .87 to .92 kg. Gain was further increased to .97 kg with higher energy content and to .99 kg with higher energy and higher protein content of calf growers. Alfalfa hay intake decreased as calf grower intake increased. Wither height and heart girth increased proportionally to body weight. Water intake was variable but proportional to dry matter intake. In trial 2, 114 heifers were fed alfalfa hay with either control or higher protein and higher energy heifer (accelerated program) growers from 187 to 369 d of age. Grass hay was fed to 86 heifers from 230 to 369 d of age with the same grower rations. Daily gain increased from .83 to .93 kg with the accelerated program. Hay intake decreased with higher grower intake on the accelerated program. When fed ad libitum on both programs, grass hay intake was about 5% lower than alfalfa hay. Heart girth at 369 d of age was increased on the accelerated program but there was no effect on wither height. Growth of Holstein heifers can be accelerated up to 1 kg daily gain from 3 to 12 mo of age without excessive fattening.
The relationship between plasma GH profiles and circulating concentrations of insulin-like growth factor 1 (IGF-1) at three different planes of nutrition, chosen to represent a high, medium and low level of nutrition (3%, 1·8% and 1% dry matter of liveweight per day) was studied in 15 young Angus steers. All steers were maintained on 3% dry matter for 5 weeks, then on one of the three nutritional planes for 4 weeks and then all were returned to 3% dry matter for 3 weeks. Blood was sampled through jugular catheters at 15-min intervals for 25 h at the end of each phase of the study and additional samples were taken on 2 days each week.
Pulsatile release of GH occurred episodically with a diurnal increase during night and morning hours only in steers on high nutritional intakes. Reduced feeding at both the medium and the low plane abolished the diurnal rhythm and significantly increased mean plasma GH concentrations, the amplitude of GH pulses and the area under the GH profiles. Baseline concentrations of GH and pulse frequency did not change through nutritional manipulation. Upon realimentation, plasma GH concentrations decreased in both previously undernourished groups, with those fed 1% dry matter still having increased levels 10 days after refeeding. Plasma IGF-1 concentrations showed no periodicity. With nutritional deprivation, a decrease in IGF-1 concentration was observed only at negative energy balance (1% group). In this group plasma IGF-1 concentrations were progressively restored within 1 week of realimentation.
The different relationship between GH and IGF-1 release at each plane of nutrition suggests that at both medium and low levels of feed intake, tissue insensitivity to GH may exist peripherally and perhaps centrally. It is suggested that nutritional status may, through modulation of tissue sensitivity to GH, be a primary factor in determining growth and the regulation of the somatotrophic axis in the postnatal ruminant.
J. Endocr. (1986) 111, 209–215
No agreement exists concerning the necessity for extracting serum somatomedin (Sm) before radioreceptor assay (RRA) and RIA. We have developed a simplified system of Sm extraction which has permitted a quantitative comparison of native and extracted Sm. To 0.8 ml of a mixture of 87.5% ethanol and 12.5% 2 N HCl, 0.2 ml serum is added. After centrifugation, 0.5 ml supernatant is neutralized with 0.2 ml 0.855 M Tris base (XT). Recovery of added 125I-labeled insulin-like growth factor I ([125I]IGF-I) was nearly quantitative. Neutral gel filtration studies established that virtually all of the binding complex was removed by acid-ethanol precipitation. The addition of 100 μl Tris-neutralized acid-ethanol buffer (AE B) to the [125I]IGF-I human placental membrane RRA produced an insignificant shift in the displacement curve with patrially purified IGF reference preparation; the shift of the [125I]Sm C RIA displacement curve was greater but did not prevent accurate measurement when AE B was added to blank and standard tubes. When partially purified IGF was added to serum and extracted promptly with acid-ethanol, the added IGF was recovered completely in the extract, but when extraction was delayed until after 16 h of incubation at 4 C, there was poor recovery of added IGF, as determined by RRA. However, there appeared to be a similar recovery of endogenous Sms. The loss of added IGF was prevented by the addition of aprotinin. The RRA of XT in 9 normal sera gave results which were 2.72 ± 0.32 times higher than those obtained by direct RRA on native sera; the fold increment was 2.96 ± 0.37 when the measurements were made by Sm C RIA. Five sera from patients with hypopituitarism gave results with the RRA of XT which were only 1.12 ± 0.30 times greater than those obtained with direct assays on serum; the increment with RIA was 1.64 ± 0.23. The results of RRA on XTs in 34 sera from normal individuals, 18 patients with clinical GH deficiency, and 8 patients with acromegaly correlated well with the known GH status. We conclude that although direct serum Sm RRAs and RIAs have provided much useful information, these assays do not quantitatively measure the Sm content of serum. A simplified acid-ethanol extraction permits convenient and accurate measurement of total Sm. We suggest that direct RIA and RRA of Sm measure predominantly bound Sm. The reported lack of parallelism with equilibrium assays of native serum and the failure of quantitative recovery of Sm described here may be the result of steric and other factors which modify access of the Sm serum binding protein complex to membrane and immunobinding sites.
Fifteen Holstein heifers that were 175 +/- 4.0 d old and at BW of 175 +/- 4.9 kg were used to determine the effect of three feeding regimens from 6 to 12 mo of age on growth, blood concentration of several hormones, and milk production during first lactation. The feeding regimens consisted of two periods, the first lasting for 4 mo and the other for the subsequent 2 mo. For group A (restricted) heifers, the diet during period 1 was restricted to 85% of NRC (1988) recommendations (a daily BW gain of .7 kg); during period 2, a high energy, high protein diet was provided for ad libitum intake. Group B (control) heifers received a diet that corresponded to 100 and 90% of the NRC (1988) recommendations in periods 1 and 2, respectively. Group C (ad libitum) intake heifers received a high energy, high protein diet throughout both periods. Daily BW gains of heifers of groups A, B, and C were, respectively, .625, .768, and 1.100 kg for period 1 and 1.162, .705, and .797 kg for period 2. The different feeding regimens influenced the age at which the heifers achieved puberty but did not affect BW at puberty. Milk production during 250 d of lactation was 7056, 6070, and 5975 kg for groups A, B, and C, respectively. A statistical model that included serum derived mitogenic activity and serum prolactin of period 2 accounted for 63% of the difference in milk production at first lactation.
Protein requirements for growing and lactating ruminants Edinburgh and London. SAS " User's Guide: Statistics, Version 5.1985. SAS Institute Quantitative estimates of mammary growth dur-ing various physiological states: a review
- R L Preston
Preston, R.L., 1972. Protein requirements for growing and lactating ruminants. In: H. Swan and D. Lewis (editors) Nutrition Con-ference for Feed Manufacturers, ~016, pp. 22-37. University of Nottingham, UK. Churchill Livingston Press, Edinburgh and London. SAS " User's Guide: Statistics, Version 5.1985. SAS Institute, Gary, NC. Tucker, H.A., 1987. Quantitative estimates of mammary growth dur-ing various physiological states: a review. J. Dairy Sci., 70: 1958-1966.
Rearing intensity in dairy heifers and the effect on subsequent milk production
- Foldager
Nutrition, feeding and calves
- Cummins
Protein and energy deposition in growing Holstein heifers
- Waldo
The effect of prepubertal nutrition on lactation performance by dairy cows
- Johnson