T Sahlu

Langston University, Langston, Oklahoma, United States

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Publications (153)144.45 Total impact

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    ABSTRACT: Growing meat goats of 4 types (Boer and Spanish of both wethers and doelings) were used to evaluate conditions for a method of testing efficacy of electric-fence strand additions to barbed-wire fence used for cattle to also contain goats. Animals were allocated to 8 sets, with each set consisting of 5 groups. There was 1 goat of each of the 4 types in a group. One side of five 2.4- × 3.7-m evaluation pens consisted of barbed-wire strands at 30, 56, 81, 107, and 132 cm from the ground. Evaluation pens were adjacent to a pasture with abundant vegetation. Fence treatments (FT) were electrified strands (6 kV) at 15- and 43- (LowHigh), 15- and 23- (LowMed), 15- (Low), 23- (Med), and 43-cm (High), where Low, Med, and High abbreviations are for low, medium, and high heights from the ground, respectively. For adaptation, there were 4-wk and sequential exposures to evaluation pens: wk 1, no electric strands; wk 2, 1 strand at 0 kV; wk 3, LowHigh; and wk 4, LowHigh. There were 6 periods for measurements, each separated by 1 wk. During the 1-wk intervals on pasture, sets were exposed to 1 interval treatment without and another with 2 electric strands (6 kV) positioned next to supplement troughs, to potentially affect familiarity with electrified strands and influence subsequent behavior. All animal sets were used for measurements in period 1 in a completely randomized design (CRD). Four sets were also used in 4-wk subsequent measurement periods for a 5 × 5 Latin square (LS). All animal sets were exposed to the same FT in period 6 as in period 1. Behavior in evaluation pens was observed for 1 h with a video surveillance system in the 6 periods. There were no effects of gender and few and minor effects of preliminary and interval treatments. The percentage of animals that exited evaluation pens differed (P < 0.05) among FT, with the CRD approach in period 1 (25%, 47%, 38%, 66%, and 84%; SEM = 8.0) and with repeated measures in periods 1 and 6 (6%, 22%, 22%, 63%, and 81% for LowHigh, LowMed, Low, High, and Med, respectively; SEM = 4.9), and between breeds in periods 1 (34% and 70%) and 1 and 6 (28% and 50% for Boer and Spanish, respectively). For the LS approach, FT affected exit (31%, 23%, 16%, 35%, and 30%; SEM = 5.3) and breeds differed (P < 0.05), as well (12% and 43%). Exit decreased as period advanced (60%, 35%, 23%, 10%, and 8%, for 1, 2, 3, 4, and 5, respectively; SEM = 5.3). In conclusion, breed should be considered in the model being developed. A LS approach was not suitable, but a CRD experiment after these adaptation procedures appears promising.
    Journal of Animal Science 09/2013; 91(9):4476-85. · 2.09 Impact Factor
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    ABSTRACT: Effects of creep grazing and stocking rate (SR) on forage selection and nutritive value of the diet of Spanish does with Boer × Spanish kids and Boer × Spanish does with 3/4 Boer–1/4 Spanish kids were determined in ten 0.4-ha pastures. There were four treatments, three involving SR and one creep grazing, with two animal groups for each treatment. Groups had 4 does with 8 kids for the low SR (L), 6 does with 12 kids for the moderate SR (M), and 8 does with 16 kids for both high SR (H) and creep grazing treatments (C). Kids of the C treatment also had access to similar 0.4-ha pastures that contained the leguminous tree mimosa (Albizia julibrissin Durazz) planted in rows. A direct observation and simulation method was used to characterize the diet selected by does and kids and obtain representative samples. The latter were evaluated for nutritive value based on CP, NDF, ADF, and ADL concentrations and in vitro true DM digestibility (IVTDMD). There were no effects (P > 0.05) of stocking rate or animal type on botanical composition of the diet selected or nutritive value. Thus, when exposed to similar forage conditions, botanical composition and nutritive value of the diet selected by does and kids were similar. Although, when kids had access to a creep grazing area, mimosa tree leaves were 53% of the diet for improved nutritive value compared with grazing in the base pasture without mimosa trees (i.e., 21.9 vs. 19.8% CP, 34.1 vs. 53.8% NDF, 21.4 vs. 27.5% ADF, and 85.7 vs. 79.9% IVTDMD).
    Small Ruminant Research 01/2013; · 1.12 Impact Factor
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    ABSTRACT: Twenty-four yearling Boer × Spanish wethers were used to assess effects of different forages, either fresh (Exp. 1) or as hay (Exp. 2), on feed intake, digestibilities, heat production, and ruminal methane emission. Treatments were: 1) Sericea lespedeza (SER; Lespedeza cuneata), a legume high in condensed tannins (CT; 20% and 15% in fresh forage and hay, respectively), 2) SER supplemented with polyethylene glycol (SER-PEG; 25 g/d), 3) alfalfa (Medicago sativa), a legume low in CT (ALF), and 4) sorghum-sudangrass (Sorghum bicolor), a grass low in CT (GRASS). Experiments were 22 d, which included 16 d for acclimatization followed by a 6-d period for fecal and urine collection, and gas exchange measurement (last 2 d). Intake of OM was 867, 823, 694, and 691 g/d (SEM = 20.1) with fresh forage, and 806, 887, 681, and 607 g/d with hay for SER, SER-PEG, ALF, and GRASS, respectively (SEM = 46.6). Apparent total tract N digestion was greater for SER-PEG vs. SER (P < 0.001) with fresh forage (46.3%, 66.5%, 81.7%, and 73.2%; SEM = 1.71) and hay (49.7%, 71.4%, 65.4%, and 54.8% for SER, SER-PEG, ALF, and GRASS, respectively; SEM = 1.57). Intake of ME was similar among treatments with fresh forage (8.24, 8.06, 7.42, and 7.70 MJ/d; SEM = 0.434) and with hay was greater for SER-PEG than ALF (P < 0.03) and GRASS (P < 0.001) (8.63, 10.40, 8.15, and 6.74 MJ/d for SER, SER-PEG, ALF, and GRASS, respectively; SEM = 0.655). The number of ciliate protozoa in ruminal fluid was least for SER with fresh forage (P < 0.01) (9.8, 20.1, 21.0, and 33.6 × 10(5)/ml; SEM = 2.76) and hay (P < 0.02) (6.3, 11.4, 13.6, and 12.5 × 10(5)/ml for SER, SER-PEG, ALF, and GRASS, respectively; SEM = 1.43). Methane emission as a percentage of DE intake was lower (P < 0.01) for SER vs. ALF and GRASS with fresh forage (6.6, 8.3, 9.4, and 9.2%; SEM = 0.64) and hay (4.3, 4.9, 6.4, and 6.7% for SER, SER-PEG, ALF, and GRASS, respectively; SEM = 0.38). In summary, methane emission in this short-term experiment was similar between a legume and grass low in CT as fresh forage and hay. The CT in SER markedly decreased N digestibility and elicited a moderate decline in ruminal methane emission. Supplementation with PEG alleviated the effect of CT on N digestibility but not ruminal methane emission, presumably because of different modes of action. In conclusion, potential of using CT-containing forage as a means of decreasing ruminal methane emission requires further study, such as with longer feeding periods.
    Journal of Animal Science 03/2012; 90(8):2754-62. · 2.09 Impact Factor
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    ABSTRACT: Goats and sheep often graze together and guardian dogs are commonly used for protection from predators. The objective of this experiment was to characterise how goats, sheep and guardian dogs interact spatially when grazing the same pasture by use of global positioning system (GPS) collars as an unobtrusive means of behaviour monitoring. In 2002 and 2003, three meat goats and two sheep in a group of 12 of each species were randomly chosen and, along with a guard dog, fitted with GPS collars. Minimum distance travelled between consecutive 30-min fixes and distance between any two animals at the same fix time were calculated using spherical geometry. In 2002, the dog travelled the least between fixes during the day but more at night than either goats or sheep. However, in 2003, there was not a significant species difference in distance travelled in 24 h or during the day or night. All species travelled significantly more during day than night but none were stationary at night. Distance amongst goats and between sheep tended to be greater during day than night; distance between goats and sheep was greater than the distance amongst goats or between sheep. Hence, goats and sheep interacted as two separate entities rather than as one large herd/flock. Distance between the dog and goats was closer than between the dog and sheep, indicating a clear preference of the dog for goats that could relate to a difference in previous exposure to the two species. In summary, based on these findings protection by a guardian dog would be greater for a small group of goats than sheep and much greater than for a mixed species group. Or, with a large group of grazing animals, the number of dogs required for a certain level of protection would rank goats < sheep < mixture of goats and sheep.
    Journal of Applied Animal Research 01/2012; · 0.12 Impact Factor
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    ABSTRACT: Boer (BG) and Spanish goat (SG) and Rambouillet sheep (RS) wethers, ≥2.5yr of age, consumed grass hay ad libitum (AL) or in restricted amounts (RI). Initial BW was 50, 74, and 40kg for BG, RS, and SG, respectively. Intake of ME was 276, 230, and 281kJ/kgBW0.75 for BG, SG, and RS (SE=10.2) and 209 and 316kJ/kgBW0.75 for RI and AL, respectively (SE=7.7). Change in BW was lowest (P
    Small Ruminant Research - SMALL RUMINANT RES. 01/2012;
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    ABSTRACT: Sixteen Boer goat doelings, 16 Spanish doelings, and 8 Angora doelings and 8 wethers, 283, 316, and 330 d of age initially (SEM = 5.0), respectively, were used to evaluate effects of nutrient restriction on heat energy (HE). During the first and second 10-wk phases, 8 animals of each breed were fed a 50% concentrate pelletized diet at a level adequate for maintenance and moderate energy accretion (CONT). Other animals were fed approximately 50% of these amounts in phase 1 relative to initial BW, followed by the greater level of feeding in phase 2 based on initial or actual BW when greater (REST). Average daily gain was 43, -20, 16, -78, 8, and -48 g in phase 1 (SEM = 5.0) and 26, 44, 50, 65, 27, and 32 g in phase 2 (SEM = 3.5) for Angora-CONT, Angora-REST, Boer-CONT, Boer-REST, Spanish-CONT, and Spanish-REST, respectively. Total HE was greater for CONT vs. REST in both phases (P < 0.001), greater in phase 1 for Angora than for Boer (P < 0.01) and Spanish (P < 0.01), and greatest (P < 0.01) in phase 2 among breeds for Angora [481, 347, 430, 356, 424, and 338 kJ/kg of BW(0.75) per day in phase 1 (SEM = 11.1), and 494, 479, 445, 397, 444, and 406 kJ/kg of BW(0.75) per day in phase 2 (SEM = 11.3) for Angora-CONT, Angora-REST, Boer-CONT, Boer-REST, Spanish-CONT, and Spanish-REST, respectively]. Equations describing the temporal pattern of HE (kJ/kg of BW(0.75) per day), expressed as a percentage of the wk-0 value and corrected for corresponding breed × week CONT means, in phase 1 were 95.8 ± 2.43 - (8.18 ± 1.144 × week) + (0.655 ± 0.1098 × week(2)) for Angora (R(2) = 0.58), 95.3 ± 2.63 - (4.34 ± 1.237 × wk) + (0.271 ± 0.1187 × wk(2)) for Boer (R(2) = 0.41), and 97.4 ± 2.21 - (4.69 ± 1.068 × wk) + (0.282 ± 0.1021 × wk(2)) for Spanish (R(2) = 0.53). Phase 2 equations were 78.9 ± 2.22 + (8.74 ± 1.036 × wk) - (0.608 ± 0.0095 × wk(2)) for Angora (R(2) = 0.60), 77.5 ± 2.10 + (3.30 ± 0.978 × wk) - (0.153 ± 0.0942 × wk(2)) for Boer (R(2) = 0.39), and 80.6 ± 2.50 + (4.50 ± 1.165 × wk) - (0.208 ± 0.1122 × wk(2)) for Spanish (R(2) = 0.43). These equations indicate that changes in HE in response to nutrient restriction and realimentation were more rapid and of greater magnitude in Angora vs. Boer and Spanish. The temporal pattern of decline in HE by Boer and Spanish during restriction was similar, but the subsequent rise with realimentation was slower and smaller for Boer. In conclusion, most appropriate methods of predicting change in the maintenance energy requirement during and after periods of limited feed intake may differ among breeds of goats.
    Journal of Animal Science 07/2011; 89(12):4175-87. · 2.09 Impact Factor
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    ABSTRACT: Twenty-three Boer (75%)×Spanish (25%) multiparous does, eight with ruminal cannula, grazed grass/legume pastures in different stages of production. Four cannulated and eight non-cannulated does were confined in a building at night and had pasture access from approximately 07:00 to 19:00h (Night); other animals had continual pasture access (Past). Data collection periods 15days in length were in late gestation (L-G; 137±5.2days), early lactation (E-L; 43±2.1days), late lactation (L-L; 97±1.1days), the dry period (Dry), and early gestation (L-G; 65±5.9days). Most does had a litter size of 2, and kids were weaned at 118±1.0days. Ingesta collected from cannulated does after rumen-evacuation averaged 19.9, 12.5, 14.7, 13.4, and 19.9% CP (SE=0.59) and 50.8, 59.2, 63.1, 61.4, and 38.1% NDF in L-G, E-L, L-L, Dry, and E-G, respectively; (SE=1.55). Kid ADG tended (P
    Livestock Science - LIVEST SCI. 01/2011; 140(1):225-245.
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    ABSTRACT: Central performance testing of meat goats has increased in popularity recently, but minimum test duration has not been ascertained to assess accurately performance traits. This study was conducted to determine the minimum length of time required for accurate evaluation of growing Boer bucks for ADG, dry matter intake (DMI), DMI/BW0.75, and feed efficiency as assessed by ADG:feed intake and residual feed intake. Data were collected from 425 bucks enrolled in Langston University tests lasting 84 days from 2000 to 2009. Bucks averaged 111±25 days of age and 27±8kg BW at the beginning of the test, consumed a pelletized 50% concentrate diet ad libitum, and were weighed weekly. Daily feed intake was determined with Calan gates (American Calan, Inc., Northwood, NH) or automated MK3 FIRE feeders (Feed Intake Recording Equipment, Osborne Industries Inc., Osborne, KS). Weekly data of five performance traits were analyzed using the MIXED procedure of SAS with a repeated-measures model. Residual variance relative to that at 84 days (%) for the goats fed with Calan gates was 358, 293, 235, 193, 153, 127, 116, and 107% for ADG, 184, 173, 161, 149, 136, 123, 113, and 106% for DMI, 374, 317, 256, 203, 161, 137, 118, and 107% for DMI/BW0.75, 445, 320, 225, 162, 135, 124, 111, and 105% for ADG:feed intake, and 174, 154, 143, 128, 113, 107, 103, and 102% for residual feed intake at 28, 35, 42, 49, 56, 63, 70, and 77d, respectively. Residual variance relative to that at 84 days (%) for the goats fed with FIRE was 286, 221, 192, 174, 154, 134, 125, and 110% for ADG, 111, 113, 111, 112, 111, 107, 106, and 105% for DMI, 176, 155, 144, 130, 120, 110, 110, and 110% for DMI/BW0.75, 373, 258, 216, 171, 134, 119, 114, and 106% for ADG:feed intake, and 114, 101, 103, 95, 94, 92, 98, and 103% for residual feed intake at 28, 35, 42, 49, 56, 63, 70, and 77d, respectively. Under either Calan gates or FIRE feeding conditions, the duration of Boer buck performance tests could be decreased from the standard 84 to 63 days with little loss in accuracy.
    Small Ruminant Research - SMALL RUMINANT RES. 01/2011;
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    ABSTRACT: Boer goat (BG), Spanish goat (SG), and Rambouillet sheep (RS) wethers, ≥2yr of age, were used in a crossover experiment with 28-day periods. Diets were ad libitum consumption of wheat straw alone (CON) or with a 90% soybean meal, 10% molasses supplement given at 0.22% BW (SBM). Initial BW was 35, 55, and 32kg for BG, RS, and SG, respectively. NDF digestibility was similar among animal types and between diets. BW change tended to be lowest for RS (−92, −158, and −107g/day for BG, RS, and SG, respectively; SE=22.6). ME intake was similar among animal types (244, 230, and 259kJ/kg BW0.75 for BG, RS, and SG, respectively; SE=16.6) and greater (P
    Small Ruminant Research - SMALL RUMINANT RES. 01/2011; 98(1):111-114.
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    ABSTRACT: Angora wethers (48), approximately 6months of age and 15.7kg initial BW (SEM=0.38), were used to determine the effects of the level of feed intake and realimentation on mohair fiber growth and tissue gain. There were two 12 weeks phases in which dehydrated alfalfa pellets (18% CP and 48% NDF, DM basis) were fed. In phase 1, feed amounts were intended to provide ME adequate for 0, 15, 30, 45, 60, and 75g/day of tissue (non-fiber) gain and 0, 1.5, 3.0, 4.5, 6.0, and 7.5g/day of clean mohair fiber growth, respectively (L1, L2, L3, L4, L5, and L6, respectively), although actual levels were slightly greater; intake was ad libitum in phase 2. DM intake in both phases increased linearly (P
    Livestock Science - LIVEST SCI. 01/2011; 138(1):180-186.
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    ABSTRACT: Two experiments were conducted to determine appropriateness of conditions in a method being developed for evaluating efficacy of different electric fence additions to cattle barb wire fence for goat containment. In Experiment 1, two 6×6 Latin squares (LS), each with 24 yearling Boer goat doelings previously exposed to electric fence, were conducted. After overnight fasting, groups of four doelings were placed in 2.4×2.4 m pens without forage. One pen side was five strands of four-point barb wire (non-electrified) at 31, 56, 81, 107 and 132 cm from the ground adjacent to a pasture with abundant vegetation. One LS had periods 2–3 days in length and the other 7 days. Electric fence treatments for each square were addition to barb wire fence of four electric fence strands 15, 28, 43 and 58 cm from the ground at low voltage of 4–4.5 kV (4S-LV); two strands at 15 and 43 cm and high voltage of 8.5–9 kV (2S-HV); two strands at 15 and 43 cm and low voltage (2S-LV); one strand at 15 cm and low voltage (1S-LH-LV); one strand at 43 cm and low voltage (1S-HH-LV) and one strand at 23 cm and high voltage (1S-MH-HV). Percentages of doelings exiting (6% and 4%) and shocked in 2 h (15% and 16% for 7 and 2–3 days, respectively) were low and did not differ between period lengths. The percentage of doelings exiting in 2 h was not affected by fence treatment. Period of squares affected (p90%. With the LS method the percentage of doelings exiting also was similar among fence treatments but was 75%, 70%, 40%, 70% and 75% for 2S-HV, 2S-LV, 1S-LH-LV, 1S-HH-LV and 1S-MH-HV, respectively. With a comparison involving doeling sets used in the LS, the percentage of doelings shocked was lower (p
    Journal of Applied Animal Research - J APPL ANIM RES. 01/2011;
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    ABSTRACT: Twenty-four lactating and 13 nonlactating Alpine goats were used to determine effects of stage of lactation and dietary concentrate level on energy utilization. Diets comprising 60 or 20% concentrate (60%C and 20%C, respectively) were consumed ad libitum by lactating animals and at a level of intake near maintenance by nonlactating animals. Measurement periods were d 25 to 31 (early), 87 to 94 (mid), and 176 to 183 (late) of lactation. Eleven observations were made in early and mid lactation for each diet, and 8 and 7 were made in late lactation for the 60%C and 20%C diets, respectively. Efficiency of metabolizable energy (ME) use for maintenance (66.9, 71.4, and 61.1% for early, mid, and late lactation, respectively) and the maintenance ME requirement (479, 449, and 521 kJ/kg of BW(0.75) for early, mid, and late lactation, respectively) determined with nonlactating animals differed among stages of lactation. The efficiency of ME use for maintenance was similar between diets, but the maintenance requirement tended to be greater for the 60%C than for the 20%C diet (504 vs. 463 kJ/kg of BW(0.75)). The latter difference may have involved greater ME intake for the 60%C diet, resulting in a slightly greater difference between ME intake and total heat energy for the 60%C compared with the 20%C diet (11 vs. -8 kJ/kg of BW(0.75)). Intake of ME by lactating goats was greater for the 60%C than for the 20%C diet (18.6 vs. 16.3 MJ/d). Recovered energy in lactation from mobilized tissue tended to be greater for the 60%C than for the 20%C diet (8.44 vs. 6.55 MJ/d) and differed among stages of lactation (2.60, 1.59, and 1.13 MJ/d in early, mid, and late lactation, respectively). Recovered energy in tissue gain was similar among stages of lactation and between diets and was not different from 0. Efficiency of use of dietary ME for lactation differed among stages of lactation (59.5, 51.9, and 65.4% for early, mid, and late lactation, respectively) and tended to be greater for the 60%C than for the 20%C diet (64.2 vs. 54.9%). The efficiency of use of dietary ME for maintenance and lactation was similar among stages of lactation and was greater for the 60%C compared with the 20%C diet (64.3 vs. 60.9%). Predicted milk yield from National Research Council requirements was reasonably accurate. In conclusion, using data of nonlactating goats to study energy utilization for maintenance in lactation has limitations. Efficiency of energy use by lactating dairy goats consuming diets high in concentrate appears greater than that by goats consuming diets low in concentrate. Despite differences in nutrient requirement expressions, observations of this study support National Research Council recommendations of energy requirements of lactating dairy goats.
    Journal of Dairy Science 10/2010; 93(10):4818-28. · 2.57 Impact Factor
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    ABSTRACT: Thirty-six lactating Alpine does were used to determine effects of stage of lactation and level of feed intake on energy utilization. Twelve does were assigned to measurement periods in early, mid, and late lactation (wk 5, 13, and 27, respectively). For 6 does of each group, after ad libitum consumption of a 60% concentrate diet, feed intake was restricted to near the metabolizable energy (ME) requirement for maintenance (ME(m)) for 8 d followed by fasting for 4 d. For other does, fasting immediately followed ad libitum consumption. Intake of ME was similar among stages of lactation with ad libitum intake (22.1, 22.1, and 19.8 kJ/d in early, mid, and late lactation, respectively). The efficiency of ME use for maintenance determined with does fed near ME(m) averaged 81%. Fasting heat energy was greater for ad libitum consumption than for near ME(m) consumption [368 vs. 326 kJ/kg of body weight (BW)(0.75)] and was numerically lowest among stages in late lactation with near ME(m) intake (334, 350, and 295 kJ/kg of BW(0.75) in early, mid, and late lactation, respectively) and ad libitum consumption (386, 384, and 333 kJ/kg of BW(0.75) in early, mid, and late lactation, respectively). The efficiency of use of dietary ME for lactation was greater for consumption near ME(m) than for consumption ad libitum (67.9 vs. 58.6%) and with ad libitum consumption tended to decrease with advancing stage of lactation (63.9, 57.3, and 54.5% for early, mid, and late lactation, respectively). Estimated ME(m) was greater for ad libitum intake than for near ME(m) intake and was lowest during late lactation (429, 432, and 358 kJ/kg of BW(0.75) for near ME(m) intake and 494, 471, and 399 kJ/kg of BW(0.75) for ad libitum intake in early, mid, and late lactation, respectively). However, because of increasing BW as the experiment progressed, ME(m) (MJ/d) was similar among stages of lactation with both levels of intake. The efficiency of ME use for maintenance and lactation was similar among stages of lactation and greater with near ME(m) intake than ad libitum intake (77.1 vs. 67.7%). In conclusion, the ME(m) requirement (kJ/kg of BW(0.75)) of does in late lactation was less than in early and mid lactation. A marked effect of restricted feed intake subsequent to ad libitum consumption on estimates of efficiency of energy use for maintenance and lactation was observed compared with use of nonlactating animals. Level of feed intake can have substantial effect on estimates of energy utilization by lactating dairy goats.
    Journal of Dairy Science 10/2010; 93(10):4829-37. · 2.57 Impact Factor
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    ABSTRACT: Twelve mature Angora does were used in a replicated 3 × 3 Latin square to determine effects of feeding level on energy utilization. Fiber growth and change in tissue (nonfiber) mass were determined in the first 4 wk of 6-wk periods, preceded by 14 or 18 d of adaptation. Determination of ME intake and gas exchange measures occurred in wk 4, followed by feeding near maintenance, then fasting in wk 5 and 6 to determine the ME requirement for maintenance (ME(m)). A 60% concentrate diet was fed at levels to approximate 100, 125, and 150% of assumed ME(m) [low, medium (med), and high, respectively]. Digestibilities and diet ME/GE were not affected by treatment with different amounts of feed offered and subsequent intake near ME(m). Heat energy during fasting (261, 241, and 259 kJ/kg of BW(0.75); SEM = 8.7) and efficiency of ME used for maintenance (71.6, 69.6, and 69.2%; SEM = 2.29) were similar among treatments, although ME(m) differed (P < 0.04) between med and high (365, 344, and 377 kJ/kg of BW(0.75) for low, med, and high, respectively; SEM = 10.3). Tissue gain was less (P < 0.01) for low than for the mean of med and high (MH; -0.6, 23.7, and 29.8 g/d), although clean fiber growth only tended (P < 0.09) to differ between low and MH (5.60, 6.57, and 7.36 g/d for low, med, and high, respectively; SEM = 0.621). Intake of ME was greater (P < 0.01) for MH than for low (6.87, 8.22, and 8.41 MJ/d for low, med, and high, respectively). Total heat energy was less (P < 0.02) for low vs. MH and tended (P < 0.07) to be greater for high than for med (6.03, 6.31, and 6.77 MJ/d); mobilized tissue energy was low but greater (P < 0.02) for low vs. MH (0.16, 0.01, and 0.04 MJ/d for low, med, and high, respectively). Efficiency of ME use for fiber growth was similar among treatments (17.2, 16.3, and 17.7% for low, med, and high, respectively; SEM = 1.61). In conclusion, efficiency of ME use for fiber growth was similar to the NRC recommendation regardless of feeding level, although ME(m) was decreased perhaps because of experimental conditions used. Energy appeared partitioned to fiber growth, but preferential usage was not complete possibly because energy metabolism for tissue accretion reached a plateau with the greatest feeding level.
    Journal of Animal Science 10/2010; 89(1):142-9. · 2.09 Impact Factor
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    ABSTRACT: Multiparous Alpine does (42) were used to determine how stage of lactation and dietary forage level affect body composition. The feeding and body composition portion of the study had a 2 x 3 factorial arrangement of treatments. Eighteen does were fed a 40% forage diet (40F) and 18 received a diet with 60% forage (60F) for approximately 2, 4, or 6 mo of lactation (59 +/- 1.3, 116 +/- 1.0, and 184 +/- 1.4 d, respectively), followed by determination of body composition (6 does per diet at each time of slaughter). Does were assigned sequentially to treatments as kidding occurred. The 60F diet had 20% more dehydrated alfalfa pellets than the 40F diet, with higher levels of corn and soybean meal and inclusion of supplemental fat in the 40F diet. Initial body composition measures were made with 6 other does a few days after kidding (0 mo; 4 +/- 0.6 d). Before parturition, does were fed a 50% concentrate diet free choice. Intake of dry matter was greater for 60F than for 40F, average daily gain tended to be affected by an interaction between diet and month (0, 24, 121, -61, 46, and 73 g), and 4% fat-corrected milk was less in mo 5 to 6 than earlier. Internal fat mass was greatest among times at 6 mo and greater for 40F than for 60F. Mass of the gastrointestinal tract was less for 40F than for 60F and decreased with increasing time in lactation. Concentrations of fat in the carcass (13.8, 13.1, 16.5, 11.2, 11.5, and 14.4%), noncarcass tissues (18.6, 24.2, 33.3, 14.3, 16.5, and 24.5%), and empty body (16.5, 18.7, 25.2, 12.9, 14.1, and 19.5% for 40F at 2 mo, 40F at 4 mo, 40F at 6 mo, 60F at 2 mo, 60F at 4 mo, and 60F at 6 mo, respectively) were affected by stage of lactation and diet. Based on daily change in tissue mass and energy, energy concentration in tissue mobilized or accreted was 16, 20, and 32 MJ/kg in 1 to 2, 3 to 4, and 5 to 6 mo of lactation, respectively. In conclusion, based on tissue mass, more energy was expended by the gastrointestinal tract with 60F than with 40F. Considerable internal fat appeared to be mobilized in early lactation, particularly with the diet moderate to high in forage, with more rapid and a greater magnitude of repletion by does consuming the diet lower in forage. The concentration of energy in tissue mobilized or accreted varied with stage of lactation, being considerably greater at 5 to 6 mo of lactation than earlier.
    Journal of Dairy Science 08/2009; 92(7):3374-85. · 2.57 Impact Factor
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    ABSTRACT: Sixty growing 3/4 Boer x 1/4 Spanish (BS) and Spanish (SP) wethers were used to determine influences of diet and breed on growth and body composition. A pelleted 50% concentrate diet (CD) and a diet based on grass hay (HD) were fed for ad libitum intake. Six wethers of each breed were slaughtered at 0 wk (total of 12). Six wethers of each diet-breed combination were slaughtered at 14 and 28 wk (24 per time) after consumption of the CD or HD. Initial BW of fed wethers were 21.6 and 18.8 kg for BS and SP, respectively (SEM = 0.7). Average daily gain during the entire experiment was influenced by an interaction (P < 0.05) between breed and diet (199, 142, 44, and 50 g/d for BS:CD, SP:CD, BS:HD, and SP:HD, respectively). Carcass mass was greater (P < 0.05) for CD vs. HD (56.2, 56.2, 53.2, and 54.0% of empty BW for BS:CD, SP:CD, BS:HD, and SP:HD, respectively). Mass of the liver (2.11, 1.92, 2.00, and 1.98% of empty BW; SEM = 0.05) and gastrointestinal tract (5.50, 4.83, 8.43, and 8.36% of empty BW for BS:CD, SP:CD, BS:HD, and SP:HD, respectively; SEM = 0.16) tended (P < 0.07) to be influenced by an interaction between breed and diet. Mass of internal fat (12.2, 12.1, 3.4, and 3.4% empty BW for BS:CD, SP:CD, BS:HD, and SP:HD, respectively; SEM = 0.3) differed (P < 0.05) between diets. Energy in the carcass (320, 236, 87, and 79 MJ), noncarcass tissues (318, 237, 77, and 72 MJ), and empty body (638, 472, 164, and 150 MJ) ranked (P < 0.05) BS:CD > SP:CD > BS:HD and SP:HD. Empty body concentration of protein was 18.3, 17.5, 18.3, and 19.7% (SEM = 0.3) and of fat was 24.0, 23.4, 10.8, and 10.3% for BS:CD, SP:CD, BS:HD, and SP:HD, respectively (SEM = 0.6). Energy concentration in accreted tissue was 17.0, 18.7, 16.3, and 6.4 MJ/kg for CD:wk 1 to 14, CD:wk 15 to 28, HD:wk 1 to 14, and HD:wk 15 to 28, respectively (SEM = 1.4). In conclusion, relatively high growth potential of growing Boer crossbred goats with a moderate to high nutritional plane does not entail a penalty in realized growth when the nutritional plane is low. Body composition of growing Boer and Spanish goats is fairly similar regardless of growth rate. For growing meat goats other than with a prolonged limited nutritional plane, an average energy concentration in accreted tissue is 17.3 MJ/kg.
    Journal of Animal Science 05/2009; 87(9):2913-23. · 2.09 Impact Factor
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    ABSTRACT: Eight Boer (75%) x Spanish (BS) and 8 Spanish (S) wethers (155 +/- 8 d of age and 19.2 +/- 2.3 kg of BW initially) were used in a replicated crossover design with a 2 x 2 factorial arrangement of treatments to determine effects of genotype, diet quality, and time of day on energy expenditure (EE), heart rate (HR), and EE:HR with ad libitum, near maintenance, and fasting levels of feed intake. Diets were 65% concentrate or coarsely ground alfalfa hay. Energy expenditure was ranked (P < 0.05) ad libitum > maintenance > fasting (500, 390, and 270 kJ/kg of metabolic BW). Heart rate did not differ between genotypes when fasting and with maintenance intake, but was greater (P < 0.05) for S than for BS when intake was ad libitum (BS: 55, 71, and 92; S: 52, 72, and 100 beats/min for fasting, maintenance, and ad libitum, respectively, SEM = 2.0). There was an interaction in EE:HR (P < 0.05) between level of feed intake and genotype (BS: 5.31, 5.59, and 5.00; S: 5.07, 5.57, and 5.22 kJ/kg of metabolic BW:beat/min for ad libitum, maintenance, and fasting, respectively, SEM = 0.13), without an effect of diet. The effect of time on EE, HR, and EE:HR differed among levels of intake (P < 0.05). General patterns of change in EE and HR as time of day advanced did not differ, but increases near meals followed by decreases were of slightly greater magnitude for maintenance than for ad libitum intake. The ratio of EE:HR was greater for the maintenance level of feed intake than for ad libitum intake at most times. These results indicate similar potential for use of HR to predict EE of different genotypes of growing meat goats and that establishing EE:HR with different diets or levels of intake may not be crucial. Magnitudes of difference among hours suggest that when EE:HR is used to predict EE of confined goats from full-day measurement of HR, EE:HR should be determined over an extended period of time, such as 24 h.
    Journal of Animal Science 02/2009; 87(5):1714-21. · 2.09 Impact Factor
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    ABSTRACT: Eight Spanish and eight Boer yearling doelings were used to assess relationships between energy expenditure (EE) and ambient temperature (Ta), relative humidity (RH), and temperature–humidity index (THI). Four doelings of each genotype were housed in two 5.6m×3.1m pens of an enclosed facility with a concrete floor without cooling and with heat provided only to prevent damage to waterers and water lines from freezing. EE was determined over 2-day periods 13 times during a 1 year period based on EE:heart rate (HR) of each doeling. Climate variables were averaged over 2, 4, 6, and 8 weeks preceding EE measurement. Doelings were fed to meet the maintenance energy requirement (MEm). Average mean, low, and high values during the 2 weeks preceding EE determination were 19.9, 7.9, and 31.8°C for Ta and 53.6, 36.1, and 62.5% for RH, respectively. Neither Ta nor THI were correlated with or had significant effects in regressions to predict the difference between EE at particular measurement times and the 1 year mean (EEdiff). Conversely, RH was correlated (P
    Small Ruminant Research - SMALL RUMINANT RES. 01/2009; 81(1):42-54.
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    ABSTRACT: Goat research in the United States has increased but at a rate less than that in production. Research on goat meat includes nutritional quality, packaging, color, sensory characteristics, and preslaughter management. Goat skins have value for leather, but quality of goat leather has not been extensively studied. Research in the production, quality, antibiotic residues, and sensory characteristics of goat milk and its products has aided development of the US dairy goat industry. Limited progress has been made in genetic improvement of milk or meat production. There is need to explore applications of genomics and proteomics and improve consistency in texture and functionality of goat cheeses. New goat meat and milk products are needed to increase demand and meet the diverse tastes of the American public. Despite research progress in control of mohair and cashmere growth, erratic prices and sale of raw materials have contributed to further declines in US production. Innovative and cooperative ventures are needed for profit sharing up to the consumer level. Internal parasites pose the greatest challenge to goat production in humid areas largely because of anthelmintic resistance. Study of alternative controls is required, including immunity enhancement via nutrition, vaccination, pasture management such as co-grazing with cattle, and genetic resistance. Similarly, the importance of health management is increasing related in part to a lack of effective vaccines for many diseases. Nutrition research should address requirements for vitamins and minerals, efficiencies of protein utilization, adjusting energy requirements for nutritional plane, acclimatization, and grazing conditions, feed intake prediction, and management practices for rapid-growth production systems. Moreover, efficient technology transfer methods are needed to disseminate current knowledge and that gained in future research.
    Journal of Animal Science 10/2008; 87(1):400-18. · 2.09 Impact Factor
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    ABSTRACT: Twenty-four yearling Boer x Spanish goats were used in a crossover experiment to determine the effects of tethering on herbage selection, intake and digestibility, grazing behavior, and energy expenditure (EE) with high-quality herbage. Four 0.72-ha paddocks of wheat (Triticum aestivum) and berseem clover (Trifolium alexandrium) were grazed in the spring. Each paddock hosted 6 animals, 3 with free movement and 3 attached to a 3-m tether that was moved daily and provided access to an area of 28.3 m(2). One animal of each treatment and paddock was used to determine herbage selection, fecal output, or grazing behavior and EE. Herbage DM mass in tethered areas before grazing averaged 2,649 and 2,981 kg/ha in periods 1 and 2, respectively. The CP concentration in ingesta was greater (P < 0.05; 23.1 and 20.3 +/- 0.82%) for free vs. tethered animals, although in vitro true DM digestion (75.7 and 76.5 +/- 1.20%, respectively) did not differ (P > 0.05) between treatments. Intake of ME based on in vitro true DM digestion and fecal output was greater (P < 0.05) for free vs. tethered animals (12.7 and 10.4 +/- 0.89 MJ/d). No treatment effects were observed (P > 0.05) for time spent ruminating or grazing (405 and 366 +/- 42.5 min/d, respectively), although mean EE was greater (P < 0.05) for free vs. tethered animals (633 and 512 +/- 27.4 kJ/kg of BW(0.75) for free and tethered, respectively), with differences (P < 0.05) between treatments at each hour of the day. Tethering animals may be acceptable to model those with free movement for some measures such as ingesta composition but appears inappropriate for others, such as energy metabolism.
    Journal of Animal Science 05/2008; 86(5):1245-53. · 2.09 Impact Factor

Publication Stats

1k Citations
144.45 Total Impact Points

Institutions

  • 1992–2013
    • Langston University
      Langston, Oklahoma, United States
  • 2004
    • Massey University
      • Institute of Veterinary, Animal and Biomedical Sciences
      Palmerston North City, Manawatu-Wanganui, New Zealand
    • Fujian Agriculture and Forestry University
      Min-hou, Fujian, China
  • 2000
    • Institute of Animal Science, Kostinbrod
      Костинброд, Sofiya, Bulgaria
    • Dire Dawa University
      Daredawa, Dire Dawa Region, Ethiopia
  • 1999
    • Louisiana State University
      • School of Animal Sciences
      Baton Rouge, LA, United States
  • 1988
    • University of California, Davis
      Davis, California, United States