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Wu G.,Texas A&M University | Wu G.,China Agricultural University | Bazer F.W.,Texas A&M University | Burghardt R.C.,Texas A&M University | And 8 more authors.
Amino Acids

Proline plays important roles in protein synthesis and structure, metabolism (particularly the synthesis of arginine, polyamines, and glutamate via pyrroline-5-carboxylate), and nutrition, as well as wound healing, antioxidative reactions, and immune responses. On a per-gram basis, proline plus hydroxyproline are most abundant in collagen and milk proteins, and requirements of proline for whole-body protein synthesis are the greatest among all amino acids. Therefore, physiological needs for proline are particularly high during the life cycle. While most mammals (including humans and pigs) can synthesize proline from arginine and glutamine/glutamate, rates of endogenous synthesis are inadequate for neonates, birds, and fish. Thus, work with young pigs (a widely used animal model for studying infant nutrition) has shown that supplementing 0.0, 0.35, 0.7, 1.05, 1.4, and 2.1% proline to a proline-free chemically defined diet containing 0.48% arginine and 2% glutamate dose dependently improved daily growth rate and feed efficiency while reducing concentrations of urea in plasma. Additionally, maximal growth performance of chickens depended on at least 0.8% proline in the diet. Likewise, dietary supplementation with 0.07, 0.14, and 0.28% hydroxyproline (a metabolite of proline) to a plant protein-based diet enhanced weight gains of salmon. Based on its regulatory roles in cellular biochemistry, proline can be considered as a functional amino acid for mammalian, avian, and aquatic species. Further research is warranted to develop effective strategies of dietary supplementation with proline or hydroxyproline to benefit health, growth, and development of animals and humans. © 2010 Springer-Verlag. Source

Xue M.,Chinese Academy of Agricultural Sciences | Yun B.,Chinese Academy of Agricultural Sciences | Yun B.,Ocean University of China | Wang J.,Chinese Academy of Agricultural Sciences | And 5 more authors.
Aquaculture Nutrition

An 8-week growth trial was conducted using a 2×3 factorial design to evaluate the effect of substitution of fishmeal (FM) by rendered animal protein blend [APB, comprised of 400gkg -1 poultry by-product meal, 350gkg -1 meat and bone meal, 200gkg -1 hydrolysed feather meal (HFM) and 50gkg -1 spray-dried blood meal] in diets of Siberian sturgeon, Acipenser baerii Brandt. Two isoenergetic control diets were formulated to contain two different protein levels [high-protein control (400gkg -1), with 483gkg -1 of FM] and [low-protein control (360gkg -1), with 400gkg -1 of FM]. At each protein level, dietary FM protein was replaced by APB at 75% and 100% levels and supplemented with crystallized essential amino acid under ideal protein concept. The six diets were named as HC, HAPB75, HAPB100, LC, LAPB75 and LAPB100, respectively. No significant differences were found in weight gain rate (WGR) and specific growth rate (SGR), but fish fed with the low-protein diets showed higher feed intake and feed conversion ratio. Plasma growth hormone and insulin-like growth factors I of each group were not significantly different (P>0.05). The whole-body composition and liver composition were not affected by dietary protein levels, replacement or their interaction. Muscle protein and lipid contents of fish fed with diet LAPB100 were significantly lower than those of HC group. Digestibility of nitrogen (N) and phosphorus (P) were reduced with higher APB inclusion levels, but productive N and P values of all groups were not different. Lower N and P intake induced lower nutrients losses (P<0.05). The results suggested that dietary protein level could be reduced to 360gkg -1 from 400gkg -1 without affecting WGR or SGR and significantly reduced nutrients lose. Furthermore, dietary FM protein can be totally replaced by APB in feed formulation either at 400gkg -1 or at 360gkg -1 protein level. © 2012 Blackwell Publishing Ltd. Source

Li X.,Texas A&M University | Rezaei R.,Texas A&M University | Li P.,National Renderers Association | Wu G.,Texas A&M University
Amino Acids

Dietary amino acids (AA) are crucial for animal growth, development, reproduction, lactation, and health. However, there is a scarcity of information regarding complete composition of "nutritionally nonessential AA" (NEAA; those AA which can be synthesized by animals) in diets. To provide a much-needed database, we quantified NEAA (including glutamate, glutamine, aspartate, and asparagine) in feed ingredients for comparison with "nutritionally essential AA" (EAA; those AA whose carbon skeletons cannot be formed by animals). Except for gelatin and feather meal, animal and plant ingredients contained high percentages of glutamate plus glutamine, branched-chain AA, and aspartate plus asparagine, which were 10-32, 15-25, and 8-14% of total protein, respectively. In particular, leucine and glutamine were most abundant in blood meal and casein (13% of total protein), respectively. Notably, gelatin, feather meal, fish meal, meat and bone meal, and poultry byproduct had high percentages of glycine, proline plus hydroxyproline, and arginine, which were 10-35, 9.6-35, and 7.2-7.9% of total protein, respectively. Among plant products, arginine was most abundant in peanut meal and cottonseed meal (14-16% of total protein), whereas corn and sorghum had low percentages of cysteine, lysine, methionine, and tryptophan (0.9-3% of total protein). Overall, feed ingredients of animal origin (except for gelatin) are excellent sources of NEAA and EAA for livestock, avian, and aquatic species, whereas gelatin provides highest amounts of arginine, glycine, and proline plus hydroxyproline. Because casein, corn, soybean, peanut, fish, and gelatin are consumed by children and adults, our findings also have important implications for human nutrition. © 2010 Springer-Verlag. Source

Zhu H.,Beijing Normal University | Zhu H.,Beijing Fisheries Institute | Gong G.,Chinese Academy of Agricultural Sciences | Wang J.,Chinese Academy of Agricultural Sciences | And 5 more authors.
Aquaculture Nutrition

An 8w growth trial was conducted to determine the effect of partial replacement of fish meal (FM) by a blend of rendered animal protein (BAP, comprised of 40% meat and bone meal, 40% poultry by-product meal, 20% hydrolyzed feather meal in diets for juvenile Siberia sturgeon (Acipenser baerii Brandt). Five experimental diets were formulated. The control diet (C) contained 48% FM, whereas in the remaining four diets, FM were replaced by BAP at 25% or 50% level balanced by crystallized amino acid (AA) or spray-dried blood meal (BM), which named as BAP25-AA, BAP25-BM, BAP50-AA and BAP50-BM, respectively. Weight gain rate of BAP50-AA group was significantly higher than that of C group, while other BAP diets did not show negative effect on growth performance. The BAP25-BM group exhibited the lowest feed conversion rate (FCR) (P<0.05). FM replacement by BAP did not affect chemical composition of the whole body and crude fat level of the liver, but significantly affect the fillet lipid content. Hepatic aspartate aminotransferase and serum total protein, total cholesterol and triglyceride were reduced in fish fed diet BAP50B. Siberian sturgeon showed high efficiency on utilization of crystalline amino acid as good as those from BM. © 2010 Blackwell Publishing Ltd. Source

Wang J.,Ocean University of China | Wang J.,Chinese Academy of Agricultural Sciences | Yun B.,Ocean University of China | Yun B.,Chinese Academy of Agricultural Sciences | And 4 more authors.
Aquaculture Research

A digestibility and a growth trial were conducted in this study respectively. Firstly, the apparent digestibility coefficients (ADC) of nutrients and energy in meat and bone meal, porcine meal (PM), hydrolysed feather meal, poultry by-products meal, fishmeal (FM), soybean meal and spray-dried blood meal were determined. In experiment 2, an 8-week growth trial was conducted to evaluate the effects of the substitution of FM by PM under the digestible ideal protein concept at two protein levels in the diets of Japanese seabass, Lateolabrax japonicus. A FM-based control diet (FM diet; FM: 320gkg -1, crude protein: 434.9gkg -1, crude lipid: 124.6gkg -1) and three other diets were formulated to contain 115gkg -1 PM and only 160gkg -1 FM. Two diets were formulated on a crude protein basis without (PM diet) or with (PMA diet) essential amino acid (EAA) supplementation respectively. A low-protein diet was designed (LPMA diet, crude protein: 400.9gkg -1, crude lipid: 96.3gkg -1) with the same level of FM and PM but with the same digestible protein/ digestible energy and EAA profile as the FM diet. The results showed that nitrogen and total amino acid digestibility of the tested ingredients were ranged from 85.6% to 95.5% and from 87.6% to 95.5% respectively. Apparent digestibility coefficients of protein for FM and PM were 91.2% and 95.9% respectively. In the growth trial, the weight gain rate and feed conversion ratio of fish fed the PMA diet did not show a significant difference from those of the control group, but were significantly higher than those of the PM and LPMA groups (P<0.05). Growth was related linearly to lysine and methionine intakes. It was shown that PM could be utilized in the Japanese seabass diet up to 115gkg -1 to replace about 160gkg -1 of FM protein under an ideal protein profile. Essential amino acid deficiency (diet PM) or a lower protein level despite having an ideal amino acid profile (diet LPMA) could not support the optimal growth of Japanese seabass. © 2011 Blackwell Publishing Ltd. Source

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