-
[show abstract]
[hide abstract]
ABSTRACT: Grinding is a technological process widely applied in the feed manufacturing industry and is a prerequisite for obtaining representative samples for laboratory procedures (e.g. gas production analysis). When feeds are subjected to technological processes other than grinding (e.g. expander treatment), grinding afterwards may disturb the effect of processing, both in practice and when laboratory techniques are applied. Therefore, this study aimed to establish the possible effects of different grinding procedures and sample preparation on the degradative behaviour of expander processed barley and peas. Samples of expander processed barley and peas were subjected to six different sample preparation procedures (intact sample, dissolved sample, samples ground stepwise over 6 and 3 mm sieves, samples ground stepwise over 6, 3 and 1 mm sieves, samples ground over a 3 mm sieve and samples ground over a 1 mm sieve). The patterns of gas production in these samples were studied over a period of 72 h incubation using an automated in vitro gas production system. The particle size distribution determined by dry sieve analysis and the Coulter counter method changed due to the different grinding procedures. Grinding the samples of expander processed barley and peas changed the kinetics of gas production and led to a faster degradation, most pronounced after stepwise grinding. However, the formation of the fermentation end-product was not affected by the method of sample preparation. In expander processed barley, the difference in the degradation pattern due to the different grinding procedures was small. Copyright © 2007 Society of Chemical Industry
Journal of the Science of Food and Agriculture 04/2007; 87(5):855 - 864. · 1.44 Impact Factor
-
Seerp Tamminga
[show abstract]
[hide abstract]
ABSTRACT: Reproduction in dairy cattle is negatively affected by a negative energy balance (NEB), a combination of the deposition or mobilisation of fat and protein. The mode of action of NEB on fertility is not always clear, but the severity, length, and probably also the nature of the NEB may be involved. Extensive mobilisation of fat is expected to have detrimental effects on liver function due to the accumulation of non-esterified long chain fatty acids, impairing the detoxification of ammonia into urea. Protein evaluation systems nowadays use the concept of metabolisable protein (MP) and distinguish between rumen degradable protein (RDP) and rumen undegradable protein (RUP). Mobilisation of protein itself does not seem to have negative effects on reproduction. However, when protein is extensively degraded in the rumen or used as an energy source, metabolic residues like ammonia and urea will result. Such residues may exert metabolic effects that are often detrimental to reproduction and fertility. Ammonia is believed to play a role starting before ovulation, whereas urea mainly interferes negatively after fertilisation. But, urea is also believed to aggravate the severity of NEB and its effect on fertility by preventing or delaying the start of cyclicity. Besides, urea has been shown to lower the pH in the uterine fluid, giving rise to disturbances in follicular development and embryonic growth. It is recommended to limit the level of rumen degradable protein in the diet to 10% in the DM.
Animal Reproduction Science 01/2007; 96(3-4):227-39. · 1.75 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Animal production systems convert plant protein into animal protein. Depending on animal species, ration and management, between 5% and 45 % of the nitrogen (N) in plant protein is converted to and deposited in animal protein. The other 55%-95% is excreted via urine and feces, and can be used as nutrient source for plant (= often animal feed) production. The estimated global amount of N voided by animals ranges between 80 and 130 Tg N per year, and is as large as or larger than the global annual N fertilizer consumption. Cattle (60%), sheep (12%) and pigs (6%) have the largest share in animal manure N production. The conversion of plant N into animal N is on average more efficient in poultry and pork production than in dairy production, which is higher than in beef and sheep production. However, differences within a type of animal production system can be as large as differences between types of animal production systems, due to large effects of the genetic potential of animals, animal feed and management. The management of animals and animal feed, together with the genetic potential of the animals, are key factors to a high efficiency of conversion of plant protein into animal protein. The efficiency of the conversion of N from animal manure, following application to land, into plant protein ranges between 0 and 60%, while the estimated global mean is about 15%. The other 40%-100% is lost to the wider environment via NH(3) volatilization, denitrification, leaching and run-off in pastures or during storage and/or following application of the animal manure to land. On a global scale, only 40%-50% of the amount of N voided is collected in barns, stables and paddocks, and only half of this amount is recycled to crop land. The N losses from animal manure collected in barns, stables and paddocks depend on the animal manure management system. Relative large losses occur in confined animal feeding operations, as these often lack the land base to utilize the N from animal manure effectively. Losses will be relatively low when all manure are collected rapidly in water-tight and covered basins, and when they are subsequently applied to the land in proper amounts and at the proper time, and using the proper method (low-emission techniques). There is opportunity for improving the N conversion in animal production systems by improving the genetic production potential of the herd, the composition of the animal feed, and the management of the animal manure. Coupling of crop and animal production systems, at least at a regional scale, is one way to high N use efficiency in the whole system. Clustering of confined animal production systems with other intensive agricultural production systems on the basis of concepts from industrial ecology with manure processing is another possible way to improve N use efficiency.
Science in China Series C Life Sciences 09/2005; 48 Suppl 2:871-87. · 1.61 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: The (15)N-isotope dilution technique ((15)N-IDT), with either pulse-dose oral administration or continuous i.v. administration of [(15)N]-l-leucine (carotid artery), both at 5 mg/(kg body weight . d), was used to measure ileal (postvalve T-cecum cannula) endogenous nitrogen recovery (ENR) in pigs (9 +/- 0.6 kg). Diets were cornstarch, enzyme-hydrolyzed casein with no (control) or high (4%) content of quebracho extract (Schinopsis spp.) rich in condensed tannins. Blood was sampled from a catheter in the external jugular vein. Mean plasma (15)N-enrichment at d 8-10 was higher (P = 0.0009) after i.v. than after oral administration [0.0356 vs. 0.0379 atom% excess (APE)]. Plasma (15)N-enrichment for i.v. infused pigs was 0.01117 APE higher (P < 0.0001) and for orally dosed pigs 0.0081 APE lower (P < 0.0001) at 11 h postprandial compared with 1 h postprandial. Apparent ileal N digestibility was higher (P < 0.0001) for the control (85.5%) than for the quebracho diet (69.5%). ENR was calculated from the ratio of (15)N-enrichment of plasma and digesta. The ENR for the quebracho diet was approximately 300% higher than for the control diet (6.03 vs. 1.94 g/kg dry matter intake, P < 0.001). The real N digestibility (92.2 +/- 0.4%) was equal for both diets (P = 0.1030) and both tracer methods (P = 0.9730). We concluded that oral administration of [(15)N]leucine provides reasonable estimates of ENR in pigs fed semipurified diets with high or low content of tannins; however, one must be careful in extrapolating this conclusion to studies with other protein sources or feeding frequencies.
Journal of Nutrition 11/2004; 134(11):3068-75. · 3.92 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Ileal endogenous nitrogen recovery (ENR) in pigs (9 +/- 0.6 kg body weight) was estimated simultaneously using the (15)N-isotope dilution technique ((15)N-IDT) and the peptide alimentation ultrafiltration (UF) method. Diets were cornstarch, enzyme-hydrolyzed casein with no (control) or high (4%) content of quebracho extract (Schinopsis spp.) rich in condensed tannins. The amino acid (AA) pattern of the ENR was also determined. The ENR of pigs fed the quebracho diet was higher (P = 0.0001) than that of pigs fed the control diet [6.00 vs. 1.95 g/kg dry matter intake (DMI) for the (15)N-IDT and 5.18 vs. 1.49 g/kg DMI for the UF method, respectively]. With the (15)N-IDT, ENR values were 0.44-0.79 g/kg DMI (24%) higher (control P = 0.0032, quebracho P = 0.0002) than for the UF method. Apparent nitrogen digestibility depended on diet (69.0% quebracho vs. 86.0% control, P = 0.0001). Real nitrogen digestibility (RD-N) determined by the UF method was higher (P = 0.0001) for the control than for the quebracho diet (91.4 vs. 88.2%). Corresponding values for the (15)N-IDT did not differ (P = 0.0569) between diets (92.8 vs. 91.4%). The (15)N-IDT gave higher values for RD-N of both diets (control P = 0.0030, quebracho P = 0.0002) compared with the UF method. Endogenous AA recoveries (g/kg DMI) were increased 300% (P = 0.0001) and the AA-pattern of ENR was changed (P from 0.0001 to 0.7530 for different AA) by the quebracho diet. A constant AA-pattern of ENR cannot be assumed. Despite limitations of both techniques, the (15)N-IDT and the UF method gave similar results with respect to ENR.
Journal of Nutrition 11/2004; 134(11):3076-82. · 3.92 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: The effect of fermentable carbohydrates (sugar beet pulp and fructooligosaccharides) on the faecal bacterial communities of weaning piglets was analysed using 16S rDNA-based approaches. Amplicons of the V6-V8 variable regions of bacterial 16S rDNA were analysed by denaturing gradient gel electrophoresis (DGGE), cloning and sequencing. Differences in piglet faecal bacterial community structure were determined based on the Dice coefficients for pairwise comparison of the DGGE fingerprints and revealed significant changes in the faecal microbiota immediately after weaning. Piglets fed with fermentable carbohydrates showed a higher bacterial diversity and a more rapid stabilisation of the bacterial community compared with that of the animals fed with the control diet. Thirteen dominant DGGE bands were matched with sequences that showed 91-97% similarity to those derived from the Clostridium coccoides group and the Clostridium leptum subgroup. Amplicons related to Ruminococcus-like species were found in all DGGE fingerprints derived from pigs on the diet containing sugar beet pulp and fructooligosaccharides, but not in pigs on the control diet. These results indicate that these bacteria may play a role in the utilisation of dietary fibres.
FEMS Microbiology Ecology 04/2003; 43(2):225-35. · 3.41 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: The effect of adding steam (at 0·6 and 1·2 bar) and water (1·9% and 64% of the flux of soy grits) in a conventional barrel type conditioner and its effects on protein dispersibility index (PDI), nitrogen solubility in 0·2% KOH and trypsin inhibitor activity (TIA) of commercial soy grits was studied. In addition, conditioned soy grits were subjected to expander treatment at two different screw speeds (2 and 3 rps) and PDI, NSI and TIA were measured. Analysis of variance was used to determine the effects of steam pressure, water addition and screw speed on the mentioned protein quality parameters. In addition, resultant temperature from steam addition was used in an analysis of covariance to determine the effects of temperature as a covariate, water addition and screw speed on protein quality parameters. A significant interaction for steam pressure and water addition was found on all parameters. The highest denaturation or inactivation of the protein was found at the combination incorporating high steam and high water addition. Screw speed during expander treatment did not significantly affect protein quality parameters. It was concluded both from this study and from literature that PDI is a better parameter to evaluate technological treatments when low amounts of motor power are dissipated (<110 kJ kg-1) and that NSI in 0·2% KOH is a better parameter to discriminate between technological treatments when moderate to high amounts of motor power are dissipated in soy grits. TIA decreased with increasing water or steam content. The effect of trypsine inhibitor inactivation in soy grits was highest at higher temperatures and was not affected by screw speed of the expander. © 1997 SCI
Journal of the Science of Food and Agriculture 03/1999; 74(3):392 - 400. · 1.44 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: In vitro fermentation of sugar beet pulp (SBP) was carried out to determine which bacterial species would be enriched by use of this carbohydrate source. Faeces from four weaning piglets as a source of inoculum was also compared. The microbial diversity of the prominent bacteria before and after this in vitro fermentation was analysed using denaturing gradient gel electrophoresis (DGGE) of PCR amplicons of 16S rDNA. Before fermentation, the DGGE profiles showed differences between cultures inoculated with faeces from different piglets, though some bands were common to all piglets. After fermentation of SBP, three dominant bands appeared, of which two bands appeared in all samples and one for both replicates of one piglet. Sequences of the corresponding 16S rDNA of two bands showed 92% similarity to Eubacterium eligens and 96% similarity to Lachnospira pectinoschiza, and that of the third band 95% to L. pectinoschiza.
Anaerobe.
-
[show abstract]
[hide abstract]
ABSTRACT: The pathway for oxidation of energy involves a balanced oxidation of C2 and C3 compounds. During early lactation in dairy cattle this C2/C3 ratio is out of balance, due to a high availability of lipogenic (C2) products and a low availability of glycogenic (C3) products relative of the C2 and C3 products required for milk production. This review compares studies which manipulated dietary energy source and shows that dietary energy source can affect the balance of the C2/C3 ratio, as indicated by plasma NEFA, beta-hydroxybutyrate (BHBA) and glucose levels. It is shown that glycogenic nutrients increase glucose and insulin concentrations and decrease NEFA and BHBA plasma levels. Extra lipogenic nutrients elevate NEFA and BHBA and decrease plasma glucose concentrations. Lipogenic nutrients generally increase milk fat percentage and decrease milk protein percentage, suggesting a surplus of C2 compounds. The inverse is the case for feeding extra glycogenic nutrients, implying reduced deamination and oxidation of glycogenic amino acids. Feeding extra glycogenic nutrients improved the energy balance (EB), in contrast to ambiguous results of lipogenic nutrients on EB. Moreover, glycogenic feed may reduce the severity of ketosis and fatty liver, but increased the incidence of (sub)clinical acidosis. Since studies are scarce, it seems difficult to draw conclusions on the effects of dietary energy source on reproduction. However, lipogenic nutrients decrease glucose and increase NEFA and BHBA plasma levels. High plasma NEFA and BHBA and low plasma glucose levels are associated with decreased reproductive performance, which might imply the C2/C3 compound balance to be important for reproductive function.
Reproduction Nutrition Development 45(6):665-88. · 1.90 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Recently, it has become apparent that GIT fermentation is not only of interest for ruminant animals, but also for monogastrics. While it is now widely accepted that the fermentation process and its resultant end-products can have important influences on animal health, little is known about the microbiological and immunological processes involved. In terms of animal health, most interest at the moment is focussed on those moments in animals’ lives when they are faced with sudden changes resulting in stress. The period of weaning in piglets is a typical example of this. The most easily accomplished and appropriate way to influence GIT fermentation processes is that of dietary intervention. This is reflected by the widespread interest in so-called pre- and pro-biotics. Given the complexities of the interactions occurring in the animal itself, it is hardly surprising that in vitro techniques are being widely used: firstly to examine potential substrates for their fermentability and possible inclusion in diets, and secondly, to assess changes in the microbial populations in response to these substrates. This paper will review the techniques currently in use for these two aspects of monogastric fermentation, and provide examples of their use. Évaluation in vitro des fermentations dans le tube digestif : substrats fermentescibles et activité microbienne. Il est apparu récemment que les fermentations dans le tube digestif présentent un intérêt non seulement pour les ruminants mais aussi pour les monogastriques. Alors qu’il est maintenant bien accepté que les processus fermentaires et les produits terminaux résultants peuvent avoir des effets sur la santé animale, peu de choses sont connues concernant les processus microbiologiques et immunitaires impliqués. En termes de santé animale, le principal intérêt du moment est focalisé sur ces périodes de la vie animale pendant lesquelles les animaux sont confrontés à des changements soudains conduisant à une situation de stress. Le sevrage chez le porcelet est un exemple typique de ces périodes critiques d’élevage. La manière la plus simple et la plus appropriée d’influencer les processus fermentaires digestifs est la voie alimentaire. Ceci est reflété par l’intérêt très large que représentent les prébiotiques et les probiotiques. Étant donné la complexité des interactions intervenant dans l’animal lui-même, il n’est pas surprenant que des techniques in vitro aient été largement utilisées : premièrement pour examiner les substrats potentiels pour leur fermentescibilité et leur introduction possible dans les régimes et, deuxièmement, pour évaluer les changements dans les populations microbiennes en réponse à ces substrats. Ce papier passe en revue les techniques actuellement utilisées pour ces deux aspects des fermentations chez le monogastrique, et apporte des exemples de leur utilisation.
http://dx.doi.org/10.1051/animres:2005011.
-
[show abstract]
[hide abstract]
ABSTRACT: Fermentable carbohydrates can lead to changes in the gut microflora, which may have positive consequences for health. However, often, ingredients are added to diets without prior investigating about their potential fermentability within the target animal. The experiment reported, was conducted to investigate the fermentation kinetics of some non-digestible carbohydrates (NDC) by the caecal microbial community of broiler chickens by an assessment of the cumulative gas production during fermentation of each substrate. It also aimed to study changes in the microbial community, following fermentation of these non-digestible carbohydrates, by use of polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE). Four extracted non-digestible carbohydrates (ENC): soybean meal oligo- and water-soluble polysaccharides (SMO and SMP), alfalfa meal oligo- and water-soluble polysaccharides (AMO and AMP) were studied. Two pure sugars, raffinose (RAF) and stachyose (STA) were also included. To assess the fermentability of the substrates, cumulative gas pressure was monitored continuously, for 72 h, and at the end of fermentation, pH, volatile fatty acid (VFA), and ammonia (NH3) concentrations were measured in the fermentation solution. The PCR-DGGE technique was applied to compare microbial DNA fingerprints between substrates at the end of the fermentation. The inoculum for the in vitro gas production was obtained from a mixture of caecal contents of forty 81-day-old broiler birds. Soy oligosaccharides led to significantly more butyric acid production (P<0.05) after fermentation compared with other ENC. The production of butyric acid was 155.2 mg/g DM, 100.3 mg/g DM, 84.5 mg/g DM and 71.8 mg/g DM for SMO, SMP, AMP and AMO, respectively. Soy oligosaccharides had the lowest pH (5.5) and ammonia–nitrogen concentration (199.3 mg/l) after fermentation. This was significantly different from other ENC and the pure sugars. DGGE analysis revealed that, the fingerprint of caecal bacterial communities showed some variation (C, value >60–80%) between some of the substrates. It was concluded that SMO, SMP, AMO and AMP, as well as RAF and STA were significantly different, both in terms of their fermentation kinetics and end-products using caecal contents from adult broilers. The extent to which these non-digestible, but fermentable, carbohydrates could change the microbial community of the broiler caecum, either in terms of the species detected, or its activity, needs to be investigated further, and then related to its effect on gut health in the animal itself
-
[show abstract]
[hide abstract]
ABSTRACT: Interest in fermentation within the monogastric digestive tract is growing, particularly relative to animal health. This is of particular importance in relation to the forthcoming European ban on inclusion of anti-microbial growth promotors in animal diets. Fermentable carbohydrates are recognized as having an important role in fermentation in the monogastric digestive tract, and are often added to diets without having been examined for their actual fermentability, particularly in relation to the target animal. We describe an in vitro method to assess feed ingredients, as potential components of monogastric diets, which stimulate a positive fermentation (i.e., ones which will be well fermented and produce more short-chain fatty acids (SCFA) and less ammonia). This technique requires use of a batch culture containing the test substrate and an inoculum of appropriate origin. During fermentation, cumulative gas production is measured at regular intervals, as an indicator of kinetics of the reaction. When fermentation is complete, organic matter losses and end-products such as SCFA and ammonia, are measured. This paper illustrates use of the technique with 45 carbohydrate-based ingredients using faeces from unweaned piglets as inoculum. By assessing potential fermentability of a large number of ingredients, it is possible to make an informed choice as to which substrates are most suited for inclusion in a diet. By combining results with information about transit time, diets can be designed which should stimulate desirable fermentation along the entire digestive tract. In vitro fermentability is a potentially valuable characteristic in diet design, in order to stimulate microbial activity in the digestive tract.
-
[show abstract]
[hide abstract]
ABSTRACT: Rumen fluids from fistulated buffalos (Italy-BRF) and cows (Netherlands-CRF) were used as inocula to determine the fermentation kinetics of three forages. These were corn silage (CS), grass silage (GS) and wheat straw (WS) which had originated from both regions, giving six substrates in total. Fermentation kinetics was assessed by the measurement of cumulative gas production. Organic matter (OM) loss and volatile fatty acid (VFA) concentration at the end of the fermentation period were also determined. Both BRF and CRF ranked the substrates in the same order for total VFA, total gas production and the maximum rate of substrate degradation (CS > GS > WS). However, while the ranking of substrates was the same for both species, the absolute values differed significantly between the two inocula. Gas production, expressed as cumulative volume per unit mass of incubated (OMCV, ml g-1) and as cumulative volume per unit mass of OM degraded (OM ml g-1) for CRF was consistently higher than that for BRF for all substrates (p < 0.0001). VFA production, particularly of acetic and butyric acids, was significantly (p < 0.0001) lower for BRF than for CRF, though the digestibility of OM was the same for both inocula. VFA production predicted by the use of stoichiometric equations was generally higher than the observed gas production. These equations also predicted that the calculated amount of OM utilised for microbial growth was higher for BRF than for CRF. This may explain why diets having the same energy content but less protein can be fed to buffalo since they seem to have a lower requirement for protein compared with cattle. This possibility will need to be investigated in vivo. Given the similar ranking of feedstuffs between the two sources of inocula, these results suggest that either inoculum would be suitable for use in the cumulative gas production test as a measure of feedstuff evaluation. However, given the differences in absolute values, it is recommended that inocula from the species which will receive the feedstuff should be used. Copyright © 2004 Society of Chemical Industry
-
[show abstract]
[hide abstract]
ABSTRACT: A procedure that mimics washing in the in situ incubation technique, combined with an in vitro gas and volatile fatty acids (VFAs) production technique, was used to verify the assumption that rumen degradation behaviour of material washed out of nylon bags is instantaneous and complete. In a 6 × 4 factorial arrangement of treatments with three replicates, fractions of maize, barley, milo, yellow peas, lupins (a mixture of white and spotted lupins) and round-seeded brown faba beans were subjected to an in vitro incubation technique. Fractions were whole (WHO), non-washable (NWF), insoluble washable (ISWF) and soluble washable (SWF). In a manually operated in vitro fermentation system, another 24 samples of the same substrates were fermented for VFA and ammonia analysis. Except in lupins, ISWF in the concentrate ingredients was very rich in starch. SWF was relatively rich in ash, crude protein, soluble sugars, and a residual unknown fraction but contained only a negligible quantity of starch. Thus, the fermentation characteristics of ISWF were more like WHO and NWF than SWF. Total gas production of SWF was considerably lower than the other fractions. A very rapidly degradable fraction was seen in the first phase of degradation of SWF. The pattern of fermentation end-product formation for SWF differed from that of the other fractions. Copyright © 2007 Society of Chemical Industry
