scholarly journals Plasmatic Urea Nitrogen in Growing Rabbits with Different Combinations of Dietary Levels of Lysine, Sulphur Amino Acids and Threonine

Animals ◽  
2020 ◽  
Vol 10 (6) ◽  
pp. 946
Author(s):  
Pablo Jesús Marín-García ◽  
Mari Carmen López-Luján ◽  
Luís Ródenas ◽  
Eugenio Melchor Martínez-Paredes ◽  
Enrique Blas ◽  
...  

A total of 27 experimental diets were formulated starting from the same basal mixture, with a moderate content of crude protein and digestible energy (155 g and 9.86 MJ/kg of digestible matter (DM), respectively, both estimated). The contents of lysine, sulphur amino acids and threonine were variable. The first one, close to the current recommendations (Medium, M; 8.1, 5.8 and 6.9 g/kg DM for lysine, sulphur amino acids and threonine, respectively), and two other levels were on average 15% higher (High, H; 9.4, 6.6 and 7.8 g/kg DM for lysine, sulphur amino acids and threonine, respectively) or lower (Low, L; 6.7, 4.9 and 5.7 g/kg DM for lysine, sulphur amino acids and threonine, respectively). Diets were named with three letters, indicating lysine, sulphur amino acids and threonine levels, respectively. In total, 918 weaned rabbits (28 days old) were used (34 per diet). At weaning, animals were fed ad libitum with a commercial diet until day 46, day 47 each collective cage was randomly switched to one experimental diet. At day 48, blood samples were collected at 08:00h then the animals were subjected to 10 h of fasting and a second blood sample was extracted at 21.00h. At 08:00h, Pasmatic urea nitrogen (PUN) was higher with the L level of lysine (p < 0.001), unaffected by the level of sulphur amino acids and increased with the level of threonine (p < 0.001). At 21:00h, minimum PUN was observed with the MHL diet (14.72 ± 0.661 mg/dL). Taken into account the usual recommendations (established for a diet containing 11.3 MJ DE/kg DM, and then being 0.72, 0.51 and 0.61 g/MJ DE for lysine, sulphur amino acids and threonine, respectively), these results suggest that a diet containing more lysine and sulphur amino acids per energy unit (around 0.82 and 0.67 g/MJ DE) could better fit the growing rabbit requirements, although studies on the effects of such a diet on performance and protein retention are necessary.

1988 ◽  
Vol 68 (4) ◽  
pp. 1097-1103 ◽  
Author(s):  
R. N. KIRKWOOD ◽  
P. A. THACKER ◽  
A. D. GOONERATNE ◽  
B. L. GUEDO ◽  
B. LAARVELD

A total of 32 prepubertal gilts of Yorkshire and Landrace breeding were selected at 138 d and fed ad libitum a 16.2% crude protein diet formulated to provide 13.1 MJ DE kg−1. From selection until the end of second estrus, the gilts were exposed to a boar for 30 min d−1 to facilitate the detection of pubertal and second estrous periods. From 14 d after puberty, the gilts received daily injections of either porcine growth hormone at 90 μg kg−1 body weight (GH; n = 20) or vehicle (CT; n = 12) until 24 h after the onset of second estrus and were then killed 9 d later to determine ovulation rate. Gilts not displaying a second estrus by 24 day after puberty were considered anestrus and the injection regime was halted. Anestrous gilts were killed 30–32 d after puberty and their ovaries examined for the presence of corpora albicantia and the absence of corpora lutea. Blood samples were obtained from all gilts at 14, 17, and 20 d after puberty. There was no treatment effect on the duration of the estrous cycle (20.8 vs. 21.3 d for GH and CT, respectively), but while all CT gilts cycled normally, only 55% of the GH gilts had a second estrus (P < 0.01). In those gilts having a second estrus, the daily injection of growth hormone increased ovulation rate (14.3 vs. 12.4 for GH and CT respectively; P < 0.03). Serum type 1 insulin-like growth factor (IGF-1) concentrations were higher (P < 0.001) in GH than in CT gilts, but there was no difference between cycling and anestrous GH gilts. We suggest that the effect of growth hormone on ovulation rate was mediated by increased secretion of IGF-1. The etiology of the high incidence of anestrus is, however, not known. Key words: Gilts, growth hormone, ovulation rate


1985 ◽  
Vol 65 (1) ◽  
pp. 205-210 ◽  
Author(s):  
S. LEESON ◽  
J. D. SUMMERS

Leghorn pullets were reared on one of four dietary programs formulated to (1) conventional least-cost, (2) least-cost to amino acid requirements with no specification for crude protein, (3) as (2) with cost of protein feedstuffs increased 40% and (4) corn-soybean meal. All diets contained 18% and 15% CP, or equivalents, for 0–6 and 6–18 wk, respectively. Diets were offered ad-libitum to 14 replicate groups of 10 caged pullets. Pullets fed the conventional least-cost and corn-soybean diets were heavier (P < 0.05) at 6 wk of age than pullets reared on either of the two diets formulated to amino acid specifications. At 12 and 18 wk of age, conventionally fed birds were heavier than pullets fed amino-acid-based diets, while all groups were heavier than birds fed the corn-soybean diet. To 28 wk of age, pullets reared on amino-acid-based diets under conditions of elevated protein prices, produced more eggs (P < 0.05) relative to pullets reared on treatments 2 and 4. Results confirmed that pullets can be reared on diets formulated without crude protein specifications, and that substantial use of synthetic amino acids is not detrimental to growth or early reproductive performance. Key words: Pullet growth, amino acid formulation


1986 ◽  
Vol 42 (2) ◽  
pp. 291-295 ◽  
Author(s):  
L. E. Russell ◽  
R. A. Easter ◽  
V. Gomez-Rojas ◽  
G. L. Cromwell ◽  
T. S. Stahly

ABSTRACTAn experiment conducted at two experimental stations was designed to identify the limiting amino acids in maize-soya-bean meal diets with 120 g crude protein per kg given ad libitum to pigs from 20 to 40 kg body weight. The effects of additions of tryptophan and of tryptophan plus threonine in both the presence and absence of added methionine were studied. The responses to supplemental amino acids were not significantly different at the two stations (P > 0·10). The addition of tryptophan tended to improve growth rate. However, significant improvements in rate and efficiency of gain were not realized until both tryptophan and threonine were added (P < 0·05). Interactive effects between supplemental amino acids on pig performance were not detected. Thus, the maize-soya-bean meal diet with 120 g crude protein per kg and given ad libitum to 20-kg pigs appeared to be limiting in lysine, tryptophan, threonine and possibly methionine.


1971 ◽  
Vol 22 (1) ◽  
pp. 139 ◽  
Author(s):  
RH Weston ◽  
JP Hogan

Subterranean and berseem clovers, harvested at early and late stages of maturity, were dried and offered to sheep ad libitum, or at about 90 % of ad libitum intake. Feed consumption and the times spent in ruminating and eating were measured when the forages were offered ad libitum and several aspects of digestion were studied at the restricted level of feeding. The effects of maturity on (i) forage chemical composition, (ii) nutrient digestibility, (iii) parameters relating to the movement of digesta through the stomach, (iv) ruminal volatile fatty acid production, (v) the molar proportions of individual amino acids in abomasal digesta and peripheral blood plasma, (vi) nitrogen balance, and (vii) the time and energy expenditure in ruminating and eating, were generally the same with these clovers as has been observed previously with grasses. Substantial amounts of nutrients were derived from forages harvested in the immature state, the consumption of which provided about 1200 g organic matter per day. It was calculated that under conditions of ad libitum feeding about 500 g of volatile fatty acids was produced in the rumen and 160-230 g of crude protein was digested in the intestines per day. High mean values for nitrogen balance were obtained with immature subterranean clover but the variation between sheep was large. The levels of amino acids in blood plasma were also exceptionally high with this diet. The data obtained on the digestion of immature clover forages were compared with those obtained previously with immature grass forages. The patterns of digestion were generally very similar for both types of forages and any differences observed could usually be ascribed to the higher feed intake with the clovers. The forages had similar capacities to furnish volatile fatty acids in the rumen and digested crude protein in the intestines. The calculated energy expenditure in eating and ruminating, however, was slightly lower for the clovers. The data were interpreted to indicate that if immature clovers are superior to immature grasses in promoting animal production, the superiority cannot be attributed to an inherent capacity of clovers to provide the animal with a more favourable balance of nutrients.


Author(s):  
B M Scott ◽  
A V Fisher ◽  
R A Cooper ◽  
J A Kirk

Kirk and Cooper (1983) reported two experiments in which the growth performance and carcass conformation of intensively fed dairy-bred bulls was improved by sequential implantation with Zeranol®. Two further studies have been conducted in which there has been repeat implantation of Zeranol® and detailed carcass dissection to measure precisely the effects on carcass quality.In trial A, 16 Holstein bull calves were purchased from pedigree breeders and weaned at eight weeks of age, when they were divided into two groups of eight, balanced by weight. From 8 to 12 weeks they were given commercial rearing pellets followed by a. commercial pencil and hay was given ad libitum. From 12 weeks onwards a cereal mix was offered ad libitum, formulated to give 13 MJ/kg dry matter, 160 g/kg crude protein. Hay was withdrawn from 14 weeks of age. At eight weeks of age, half the animals were implanted with 36 mg Zeranol® (Ralgro, Crown Chemical Company, Kent), and re-implanted a further three times every 70 days. Five blood samples were taken from all animals over a 15h period at about 8, 14, 33 and 43 weeks of age.


2018 ◽  
Vol 21 (4) ◽  
pp. 379-386
Author(s):  
Hee S Kim ◽  
Jin S Hong ◽  
Chang W Park ◽  
Kyung H Cho ◽  
Yoo Y Kim

Objectives This experiment was conducted to evaluate the effect of coat length and faecal hair removal on measured nutrient digestibility in longhair and shorthair cats. Methods A total of 14 adult domestic cats, with a mean ± SD body weight of 4.5 ± 1.21 kg and a mean ± SD age of 3.3 ± 1.38 years, were used for a nutrient digestibility trial. The nutrient digestibility of cats was measured by hair-included faeces and hair-removed faeces. Food was provided twice daily (09:00 h and 16:00 h) and water was provided ad libitum. Cats were adapted to a steel cage and diet for 16 days before a 10 day collection period. During the collection period, food offered, food refused and faecal output were measured daily and used for digestibility analysis. Results The digestibility of dry matter, crude protein and neutral detergent fibre (NDF) of longhair cats was underestimated by 8% ( P = 0.02), 9% ( P = 0.04) and 14% ( P = 0.04), respectively. In shorthair cats, the digestibility of dry matter, crude protein and crude ash increased by 4% ( P = 0.01), 5% ( P = 0.02) and 15% ( P <0.01), respectively, with hair-removed faeces. The nutrient digestibility between longhair and shorthair cats showed no difference when hair-included faeces were used. However, when using hair-removed faeces, the digestibility of NDF and amino acids in longhair cats were about 4–8% higher than in shorthair cats ( P <0.05). Conclusions and relevance This study showed that the nutrient digestibility values were affected by whether the hair in faeces was removed or not. Removing hair from faeces is a more precise method with which to evaluate the apparent nutrient digestibility of domestic cats.


Author(s):  
Monika Černá ◽  
Stanislav Kráčmar

The aim of this study was to investigate the effect of storage duration on amino acids content in potato tubers. Tubers of six cultivars were stored for 16 weeks. Crude protein was determined by the Kjeldahl method. The amino acid content was identified after acid hydrolysis; sulphur amino acids were oxidized with the mixture of hydrogen peroxide, formic acid and phenol. The essential amino ­acids index and chemical score was calculated. The whole egg protein was used as reference protein. The effect of storage duration and cultivar on the total amino acids content was found to be significant in all potato varieties. The level of the total amino acids contents was determined within the range of 80–87%. Similar downward trend was observed in crude protein. The essential amino acids index varied considerably among the potato cultivars, ranging from 42 to 57%. Sulfur amino acids and isoleucin were the limiting amino acids in all the investigated tubers.


2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Sonia Yun Liu ◽  
Shemil P. Macelline ◽  
Peter V. Chrystal ◽  
Peter H. Selle

AbstractThe prime purpose of this review is to explore the pathways whereby progress towards reduced-crude protein (CP) diets and sustainable chicken-meat production may be best achieved. Reduced-CP broiler diets have the potential to attenuate environmental pollution from nitrogen and ammonia emissions; moreover, they have the capacity to diminish the global chicken-meat industry’s dependence on soybean meal to tangible extents. The variable impacts of reduced-CP broiler diets on apparent amino acid digestibility coefficients are addressed. The more accurate identification of amino acid requirements for broiler chickens offered reduced-CP diets is essential as this would diminish amino acid imbalances and the deamination of surplus amino acids. Deamination of amino acids increases the synthesis and excretion of uric acid for which there is a requirement for glycine, this emphasises the value of so-called “non-essential” amino acids. Starch digestive dynamics and their possible impact of glucose on pancreatic secretions of insulin are discussed, although the functions of insulin in avian species require clarification. Maize is probably a superior feed grain to wheat as the basis of reduced-CP diets; if so, the identification of the underlying reasons for this difference should be instructive. Moderating increases in starch concentrations and condensing dietary starch:protein ratios in reduced-CP diets may prove to be advantageous as expanding ratios appear to be aligned to inferior broiler performance. Threonine is specifically examined because elevated free threonine plasma concentrations in birds offered reduced-CP diets may be indicative of compromised performance. If progress in these directions can be realised, then the prospects of reduced-CP diets contributing to sustainable chicken-meat production are promising.


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