Research Articles (Animal Sciences)

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Browsing Research Articles (Animal Sciences) by Subject "Amino acids in animal nutrition"

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    Amino acid requirements of South African Mutton Merino lambs 3. Duodenal and whole empty body essential amino acid profile
    (South African Society for Animal Science, 1999) Ferreira, A. V.; Van der Merwe, H. J.; Loest, C. A.
    The duodenal and whole empty body essential amino acid (EAA) profile of South African Mutton Merino lambs fed a standard growth diet was investigated. The data of 20 lambs were used. With the exception of phenylalanine, significant (p < 0.05) differences between the EAA concentrations of the duodenal digesta and whole empty body occurred. From the chemical score, it was concluded that the duodenal digesta was first-limiting in histidine and second-limiting in methionine, followed by threonine and arginine for the whole empty body growth of South African Mutton Merino ram lambs fed a standard diet high in rumen degradable protein. A calculated essential amino acid composition for the correction of imbalances in duodenal digesta was as follows (%): 11.21 arginine; 14.53 histidine; 8.17 isoleucine; 9.97 leucine; 8.64 lysine; 13.87 methionine; 9.97 phenylalanine; 12.54 threonine and 11.11 valine.
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    Bioavailability and bioefficacy of hemp by-products in ruminant meat production and preservation: a review.
    (2020) Semwogerere, Farouk; Katiyatiya, Chenaimoyo L. F.; Chikwanha, Obert C.; Mapiye, Cletos
    Plant by-products obtained from agro-industrial processes require valorisation to demonstrate their potential for enhancing animal health, meat production, and shelf life extension. One example is the fast-growing hemp industry, which produces seeds, leaves, seed oil, and cake. Studies on the nutritional value of hempseed cake have shown it can be a valuable source of protein in ruminant diets. However, there is limited documentation on the bioavailability and bioefficacy of hemp phytochemicals for improving ruminant health, production, and extending meat shelf life. The current review provides an overview of existing information on nutrient and phytochemical composition of hemp by-products, their bioavailability, and bioefficacy, and explores current limitations and prospects regarding their valorisation.
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    Chemical composition, true metabolisable energy content and amino acid availability of grain legumes for poultry
    (South African Society for Animal Science, 2004) Brand, T. S.; Brandt, D. A.; Cruywagen, C. W.
    Samples of sweet yellow lupins (Lupinus luteus; n = 4), broad leaf lupins (Lupinus albus; n = 12), narrow leaf lupins (Lupinus angustifolius; n = 8), faba beans (Vicia faba; n = 2), field peas (Pisum sativum; n = 4) and narbon beans (Vicia narbonensis; n = 2) were collected over a two-year period. The physical characteristics (thousand seed and hectolitre mass), chemical composition (dry matter, ash, crude protein (CP), ether extract, acid detergent fibre, neutral detergent fibre and mineral content), energy values (nitrogen corrected true metabolisable energy content (TMEn for roosters)) as well as the lysine and methionine availability (with roosters) of the samples were determined. Lupinus albus had the highest TMEn (12.49 MJ/kg), followed by field peas (11.35 MJ/kg) and narbon beans (11.25 MJ/kg), faba beans (10.90 MJ/kg), L. angustifolius (10.46 MJ/kg) and L. luteus (10.20 MJ/kg). Lupinus luteus had the highest CP concentration (393.6 g/kg) followed by L. albus (381.9 g/kg), L. angustifolius (338.9 g/kg), faba beans (260.0 g/kg), field peas (247.4 g/kg) and narbon beans (237.6 g/kg) (values on a dry matter basis). Lupinus luteus had the highest lysine concentration (22.2 g/kg), followed by L. albus (19.6 g/kg), field peas (19.3 g/kg), L. angustifolius (18.6 g/kg), narbon beans (17.5 g/kg) and faba beans (17.0 g/kg).
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    Essential amino acid requirements of meat and milk goats
    (South African Society for Animal Science, 2004) Ferreira, A. V.
    The essential amino acid (EAA) profile of the Boer goat and Saanen kids was investigated. The EAA composition of the components differed from the whole empty body (WEB) concentration. No significant differences between the two species WEB EAA composition were found. Therefore, the average empty body EAA composition (g EAA/100 g crude protein) for goats was as follows: 5.65 arginine; 2.69 histidine; 2.94 isoleucine; 7.86 leucine; 6.83 lysine; 1.83 methionine; 3.04 phenylalanine; 5.55 threonine; 4.86 valine. This composition can serve as the ideal EAA requirements for growth in meat and milk goats.
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    Evaluation of in vivo techniques for the determination of apparent ileal amino acid digestibilities in feedstuffs for piglets
    (South African Society for Animal Science, 2000) Viljoen, J.; Coetzee, S. E.; Fick, J. C.; Siebrits, F. K.; Hayes, J. P.
    Three in vivo techniques were evaluated in terms of their suitability for determination of the apparent ileal amino acid digestibility (AID) of protein sources for piglets. The techniques were: ileo-rectal anastomosis (IRA), cannulation at the distal ileum and a slaughter technique. A standard diet and three diets in which 20% of the standard diet was substituted with either skim milk powder (SMP), fish meal or roasted full-fat soya beans (FFS) were used. Piglets were weaned at 21 days of age, and the respective diets were fed in 24 equal hourly portions per day from days 29-37. Ileal digesta was collected from day 33-37 in IRA and cannulated piglets. Piglets used for the slaughter technique were killed at 37 days of age and ileal digesta was collected. Chromium in oxide was used as an indigestible marker with all three techniques. Although AID means did not differ (p > 0.05) between the different techniques, the cannulation technique resulted in the lowest variation (standard error of the mean) of all treatments (8.2 vs 13.7 and 14.1 for the slaughter and IRA-techniques respectively). AID means obtained using the cannula technique were 1.8 percentage units higher for the SMP diet than values obtained using the other techniques (83.2 versus 81.4 %), and up to 9.3 percentage units higher for the FFS diet (75.4 versus 66.1 %). Growth data suggested that the cannulation technique caused less trauma for the piglets than the IRA-technique. IRA-piglets had not yet regained their initial weaning weight by 37 days of age, while the other piglets gained weight over the trial period. The cannulation technique is the most attractive method for use with piglets in terms of the lower variation in digestibility values. Practical aspects such as ease of handling and sampling, surgical trauma and piglet stress, are also important and contribute to the selection of the cannula technique as the most appropriate.