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1.
The study was conducted to estimate the actual genetic potential for daily protein deposition of growing barrows [genotype: Piétrain x (Duroc x Landrace)]. Twenty-four pigs with an average initial body weight (BW) of 43.7 +/- 0.7 kg were used in a N-balance study. Semi-purified diets with graded levels of crude protein (45.8, 94.2, 148.0, 198.9, 255.5 and 300.2 g/kg DM) were used, based on a constant mixture of wheat, soya bean protein concentrate and potato protein concentrate as protein sources. The amino acid pattern of the diets was according to the ideal amino acid ratio for growing pigs (Wang and Fuller, 1989), with the exception of threonine (adjusted as limiting amino acid). N-balance data were used to estimate daily N-maintenance requirement (NMR = 446 mg N/BW0.67 kg/day) by regression method and the theoretical maximum of daily N-retention (PDmaxT = 3115 mg N/BW0.67 kg/day) based on N-utilization model of Gebhardt (1966) using program Mathematica 3.0. The results indicate that PDmaxT of pigs under study is much higher than results from earlier studies with older genotypes. In summary, pigs of modern genotype have a very high genetic potential for daily protein deposition and these actual data are important basic informations for estimation of amino acid requirement within the model used. Threonine requirement data depending on threonine efficiency and protein deposition (8.96, 10.45 and 12.22 g/day for 130, 145 and 160 g daily protein deposition; 50 kg body weight) are discussed. 相似文献
2.
On the basis of the results of 3 previous articles on the efficiency of amino acids in single protein sources a total of 16 protein sources was tested maintaining the limitation relations of the combination partners with regard to the additivity of the efficiencies of lysine, methionine/cystine and threonine. The results of the N metabolism measurements with a total of 60 female pigs of the country breed type (30...55 kg live weight) allow the conclusion that additive relations and thus suitable correction possibilities exist for the gross amino acid content through the amino acid efficiency for the calculation of requirement and requirement meeting. The N utilization model used (GEBHARDT 1963) is in its further development confirmed as the basis of amino acid efficiency. 相似文献
3.
With the help of an N utilization model by Gebhardt (1963) and its further development the threonine efficiency coefficients (kThr) of wheat, barley, maize, rye and peanut oil meal of different charges with a supply of L-lysine monohydrochloride, DL-methionine and DL-tryptophan was ascertained with a total of 59 female pigs of the local breed (35-45 kg live weight) by means of an N balance method. The variation range of kThr was between 0.61 and 0.87 based on a threonine effectivity of wheat gluten with lysine as standard. The derived threonine requirement for 100 g daily protein retention with a live weight of 40 kg was ascertained as 6.9 g (kThr = 1) and 9.6 kg (kThr = 0.71 as mean values of the protein sources studied). The proof of threonine limitation in the protein sources was provided by the supplementation of DL threonine. 相似文献
4.
On the basis of 87 N balance trials with growing female pigs the possibility of deriving lysine effectivity coefficients according to the difference method for proteins rich in lysine, based on proven additive relations for amino acid effectivity coefficients (Liebert et al., 1987b). The results from 9 proteins of various charges show that nutrition-physiologically relevant conclusions for lysine effectivity could be drawn under the conditions chosen. Thus the range of application of the chosen method of the registration of the effective amino acid quota in feed proteins could be significantly extended. 相似文献
5.
The assessment of the protein quality of silaged maize ear products was carried out on the basis of crude protein and amino acid analyses and of N balance measurings with growing pigs including comparative studies with maize corns and cereals. The differences found in the amino acid concentrations between the individual maize ear products could be verified on the basis of the analysed values of husks, cobs and corns. There were no significant differences in the parameters of total protein utilization (PNu, b-value) between the studied silages. The differing crude fibre content resulted, however, in reverse shifts in N excretion in faeces and urine, i.e. diminished protein digestibility was compensated by improved intermediary utilization. 相似文献
6.
The amount of endogenous N in the chyme at the end of the small intestine and the amino acid composition of the ileum chyme were ascertained with growing pigs with ileorectostomy after feeding qualitatively differentiated protein sources. In dependence on the protein used, distinct differences turned out for some amino acids with regard to their content in the ileum chyme. Bacteriologic and histologic investigations subsequent to the dissection of the test animals showed that - in comparison to the control animals-the functions of the small intestine remained the same during the time of the experiment. The experiment method described appears to be suitable for absorption investigations up to the end of the small intestine of growing pigs. 相似文献
7.
Knowledge about the amino acid requirements and the response of pigs to the amino acid supply is essential in feed formulation. A deficient AA supply results in a reduction in performance while an oversupply is costly and leads to excessive nitrogen excretion with a potentially negative environmental impact. Amino acid requirements are determined to a large extent by the protein deposition in the body and, for lactating sows, by the protein exported in the milk. The concept of ideal protein was developed more than 50 years ago and refers to a protein with an amino acid profile that exactly meets the animal’s requirement so that all amino acids are equally limiting for performance. Because Lys typically is the first-limiting amino acid, the ideal amino acid profile is often expressed relative to Lys. Although the ideal protein profile is often assumed to be constant for a given production stage, (small) changes in the ideal protein profile can occur within a production stage. This can be caused by changes in the relative contribution of the different components of amino acid requirements during the productive life on the animal (e.g. changes in the relative contribution of growth and maintenance). Amino acids requirements can be determined experimentally using dose–response studies. The design of the study, the chosen response criterion, and the statistical model affect the requirement estimate. Although considerable experimental work has been carried out to determine the requirements for Lys, Met, Thr, and Trp in growing pigs (and to a lesser extent in sows), little is known about the requirements for the other essential amino acids. Experimental dose–response studies generally focus on the requirement and less on the overall response (i.e. what are the consequences of an amino acid deficiency?). This latter aspect is, to some extent, accounted for in modelling approaches that quantify the response of the animal to the amino acid supply in a dynamic way. The paper describes the origin of ideal protein and illustrates how fundamental concepts of amino acid nutrition have been integrated in practical modeling approaches for the nutrition of growing pigs and sows. 相似文献
8.
《畜牧与生物技术杂志(英文版)》2015,(3)
Knowledge about the amino acid requirements and the response of pigs to the amino acid supply is essential in feed formulation.A deficient AA supply results in a reduction in performance while an oversupply is costly and leads to excessive nitrogen excretion with a potentially negative environmental impact.Amino acid requirements are determined to a large extent by the protein deposition in the body and,for lactating sows,by the protein exported in the milk.The concept of ideal protein was developed more than 50 years ago and refers to a protein with an amino acid profile that exactly meets the animal's requirement so that all amino acids are equally limiting for performance.Because Lys typically is the first-limiting amino acid,the ideal amino acid profile is often expressed relative to Lys.Although the ideal protein profile is often assumed to be constant for a given production stage,(small) changes in the ideal protein profile can occur within a production stage.This can be caused by changes in the relative contribution of the different components of amino acid requirements during the productive life on the animal(e.g.changes in the relative contribution of growth and maintenance).Amino acids requirements can be determined experimentally using dose-response studies.The design of the study,the chosen response criterion,and the statistical model affect the requirement estimate.Although considerable experimental work has been carried out to determine the requirements for Lys,Met,Thr,and Trp in growing pigs(and to a lesser extent in sows),little is known about the requirements for the other essential amino acids.Experimental dose-response studies generally focus on the requirement and less on the overall response(i.e.what are the consequences of an amino acid deficiency?).This latter aspect is,to some extent,accounted for in modelling approaches that quantify the response of the animal to the amino acid supply in a dynamic way.The paper describes the origin of ideal protein and illustrates how fundamental concepts of amino acid nutrition have been integrated in practical modeling approaches for the nutrition of growing pigs and sows. 相似文献
9.
Heger J Van Phung T Krizová L 《Journal of animal physiology and animal nutrition》2002,86(5-6):153-165
A series of N balance experiments using growing pigs was conducted to study the efficiency of utilization of lysine, threonine, sulphur amino acids and tryptophan and to estimate their maintenance requirements. Purified diets based on casein and crystalline amino acids as the sole source of N contained graded levels of each amino acid, corresponding to expected protein accretion rate of 0, 33, 66, 99 and 132 g/day, respectively. N retention increased linearly (p < 0.01) as the dietary concentration of the limiting amino acid increased. Based on linear regression equations relating amino acid deposition in body protein to amino acid intake, marginal efficiencies of ileal digestible amino acid utilization were calculated to be lysine 0.91, threonine 0.83, sulphur amino acids 0.85 and tryptophan 0.66. Extrapolating the regression equations to zero N retention, the daily requirements of amino acids for N equilibrium were estimated to be (mg/kg(0.75)) lysine 39, threonine 49, sulphur amino acids 46 and tryptophan 16. 相似文献
10.
After a first report on the nutrient composition and the digestibility of some newly bred varieties of cereals, information on the apparent digestibility of the amino acids in growing female pigs ascertained with the same test material is given. These data serve the evaluation of the quality of such cultivation products and the completion of the data in of feedstuffs tables and tables of the amino acid content. The newly bred barleystrains meet the requirement of digestible protein of pigs, wheat exceeds it whereas the maize samples fall short of it. The content of digestible lysine in the newly bred barleystrain approximate the requirement of growing pigs. There is ample digestible methionine + cystine in all samples. This again proves that newly cultivated barley and wheat rich in protein and lysine if accordingly supplemented with the limiting amino acid lysine can be used as sole feed for fattening pigs. Moreover, it becomes again obvious that the apparent digestibility of the amino acids can, for practical purposes, be sufficiently exactly evaluated with the help of the apparent digestibility of the crude protein of the respective feedstuff. 相似文献
11.
In order to guarantee an equally good development of ileorectostomized pigs (IRA) used for the determination of precaecal protein digestibility and the absorption of amino acids as for intact animals (INT), the supplementation of their rations with easily soluble carbohydrates and minerals is necessary. The effects of these supplements on live weight development, nitrogen balance and N utilization level were the subject of the assessment of 21 rations with 129 and 117 balance measuring resp. with growing IRA and INT pigs. Without any supplementation of the rations the N balances of the IRA pigs showed significantly lower and partly negative N balances and N utilization levels in comparison to the INT pigs. The combined supplement of easily soluble carbohydrates (100 g/kg DM intake) and 300 ... 400 ml electrolyte solution per day (approximately 1 ... 1.3 g additional Na) resulted in N balances almost equal to those of INT pigs. The supplement of both electrolyte solution and NaHCO3 (approximately 2 g Na per animal and day additionally) to a barley + lysine ration resulted in a significant increase of the N balance and N utilization in IRA pigs of a live weight between 120 and 140 kg in contrast to the control period. A supplement of carbohydrates to a ration consisting of barley + fish meal + grass meal and electrolyte supplements of 400 ml per animal and day only resulted in significantly higher N balances and N utilization levels in the live weight range up to 70 kg in comparison to the control periods, which then corresponded to those of INT pigs. There was no essential influence of carbohydrate supplementations on pigs of more than 70 kg live weight. The postileal digestibility of the crude carbohydrates (CC) of 14 rations calculated from the difference between total digestibility (faecal analysis) and precaecal digestibility (analysis of the ileal chyme of IRA pigs) showed that between 40 and 100 g (70 g on average) out of the 780 g CC per kg DM consumed disappear in the large intestine. These studies show that in the testing of concentrates and mixed feed rations the supplementation of 100 g easily soluble carbohydrates/kg DM intake should be sufficient to guarantee a normal development of IRA pigs. In addition, an oral supply of 1 to 2 g sodium in the form of electrolyte solution exceeding the requirement of INT pigs is necessary as this supplementation significantly improves the N retention of IRA pigs even heavier than 100 kg. 相似文献
12.
13.
Heger J Van Phung T Krízová L Sustala M Simecek K 《Journal of animal physiology and animal nutrition》2003,87(1-2):52-65
Five balance experiments on growing pigs were carried out to study the marginal efficiency of utilization of isoleucine, leucine, valine, histidine and phenylalanine + tyrosine and to estimate their requirements for maintenance. Purified diets based on casein and crystalline amino acids as the sole source of N contained graded levels of each amino acid, corresponding to protein accretion rates of 0, 33, 66, 99 and 132 g/day, respectively. All other essential amino acids were given in a 30% excess. N retention increased linearly (p < 0.01) as the dietary concentration of the limiting amino acid increased. Based on linear regression equations relating amino acid deposition in body protein to amino acid intake, marginal efficiencies of ileal digestible amino acid utilization were calculated to be isoleucine - 0.81, leucine - 0.81, valine - 0.82, histidine - 1.17 and phenylalanine + tyrosine - 0.67. Extrapolating the regression equations to zero N retention, the daily requirements of amino acids for N equilibrium were estimated to be (mg/kg0.75) isoleucine - 18, leucine - 33, valine - 23, histidine - 14 and phenylalanine + tyrosine - 43. 相似文献
14.
Exogenous porcine somatotropin (PST) administration stimulates protein deposition and inhibits lipogenesis, resulting in dose-related improvements in growth performance and reduction of carcass fat content. However, the associated impacts of this technology on dietary nutrient requirements and energy partitioning between maintenance, protein, and fat remain unclear. Studies with pigs between 25 and 60 kg body weight indicate that, because of unknown improvements in amino acid utilization and(or) in the energy available for protein synthesis, only marginal increases in dietary protein percentage are required to support 20 to 25% improvements in protein deposition induced by PST administration. In contrast, an increased dietary protein concentration is required to support maximal protein deposition in pigs 60 to 100 kg. Exogenous PST administration increased the maintenance energy requirement and altered the relationship between energy intake and protein deposition, although the magnitude of these changes and the consequent effects on expression of dietary protein (amino acid) requirements was influenced by gender. Albeit limited, information suggests that PST alters nutrient demand at the tissue level. Information of this type will form the basis for rational decisions concerning the method for expression of dietary nutrient requirements (% vs g/d) for PST-treated pigs. Further quantitative information is required on the effects of PST dosage on the relationship of protein deposition to energy intake and on any underlying changes in amino acid utilization and metabolism. 相似文献
15.
In N balance experiments with a total 59 growing female pigs in the live weight range of 33 to 55 kg the lysine efficiency (bc-1 value) and the lysine efficiency coefficient (kLys) of various cereal proteins were ascertained under the consideration of various charges and varieties. The range of kLys = 0.65 ... 0.96 shows a wide spectrum of lysine efficiency, which results in an analogous differentiation of the derived lysine requirement values. Assuming kLys = 1.0 (lysine efficiency 100%, i.e. the maximum value for bc-1 found as yet for native proteins) a daily lysine requirement (efficient amino acid) of 8.9, 10.8 and 12.6 g resp. was ascertained for 100 g daily protein retention at 30, 40 and 50 kg live weight resp. 相似文献
16.
The following values were derived from experimental studies of the crude protein (CP) and amino acid (AA) metabolism of growing fattening bulls, the detailed results of which were described in installments 1-6, for the ascertainment of the content of apparently digestible total protein at the duodenum (ADTPD): a) partial method: Degradation quotaCP = NPN + 0.69 X g pure protein/CP; g AD feed PD = g CP (1 -decomposition quotaCP) X 0.72 or g AD feed PD = 0.31 X g pure protein X 0.72; g ADBPDE = 0.149 X g AD org. matter X 0.80 X 0.72 (ADBPDE = apparently digestible pure bacteria protein at the duodenum, dependent on energy release in the reticulo-rumen; g ADBPDN = g CP X (degradation quotaCP) X 0.80 X 0.72 (ADBPDN = apparently digestible pure bacteria protein at the duodenum, dependent on CP supply of rumen microbes); g AD total PD = g AD feed PD + ADBPDE g AD total PD = g AD feed PD + ADBPDN; b) summarizing method: AD total PD = 0.429 + 10.9 X 0.80/CP in % AD org. matter X (CP intake) X 0.72; AD total PD = 0.196 + 16.6 X 0.80/pure protein % AD org. m. X pure pr. intake X 0.72. The requirement of AD total PD was calculated under consideration of the endogenous urine N, skin N and hair N losses as well as protein retention per kg live weight assuming a utilization of 0.70 for this partial performance. The practical application of this balance method is demonstrated in comparison to the digestible CP-system. 相似文献
17.
本研究旨在探讨低蛋白日粮对生长猪生长性能和腹泻率的影响。试验选取初始体重为16kg左右的三元（杜×长×大）健康生长猪66头,采用单因子试验设计,分为对照组和试验组,每组设3个重复,每个重复11头;对照组日粮按照NRC（1998）推荐营养需要量配制,试验组在NRC推荐日粮粗蛋白水平上降低3.8个百分点,试验期30d。结果表明,试验组日增重比对照组增加了23．4g,提高幅度为4．6％（P〈0．05）;料肉比降低了0．22,降低幅度为10．8％（P〈0．05）;试验组腹泻率与对照组相比,有下降趋势,但无显著性差异（P〉0．05）。说明使用低蛋白日粮能提高生长猪的生长性能和饲料转化率,并在一定程度上能减少仔猪腹泻。 相似文献
18.
To quantify the utilization of ME by growing pigs, a factorial analysis method is often used in which the ME intake is regressed on protein (PD) and lipid deposition (LD) rates. The approach has been criticized because there often is a strong correlation between PD and LD, which makes accurate estimation of model parameters difficult. The current study describes a nonlinear multivariate analysis procedure in which PD and LD are the result of variation in ME intake. The approach requires a hypothesis concerning the partitioning of ME intake above maintenance between PD and LD. The method was evaluated using data for growing pigs of different genotypes and sex and weighing between 20 and 107 kg that were offered a diet close to ad libitum. Energy, nitrogen, and fat balances were determined at regular intervals over the growing period. The maintenance energy requirement was expressed as a function of BW (with group-specific parameters) or as a function of muscle and visceral mass. The maintenance energy requirements ranged from 913 to 1,070 kJ ME/((kg BW).60.d) for obese castrates and boars of a synthetic line, respectively. Viscera contributed 1,558 kJ ME/ ((kg tissue).70.d) to the maintenance energy requirement, whereas muscle contributed only 555 kJ ME/ ((kg tissue).70.d). It was assumed that the proportion of ME intake (above maintenance) designated for PD declined linearly with increasing BW. At 20 kg of BW, 49% of ME intake above maintenance was designated for PD in lean genotypes, whereas this was only 34% in obese genotypes. In general, with increasing BW, less energy was designated for PD, but this relationship depended on genotype and sex. Extremely lean male genotypes maintained a constant partitioning of energy between PD and LD for all BW. The energetic efficiencies varied (depending on the model used to express the maintenance requirement) between .58 and .60 for PD and .77 and .82 for LD. Extrapolation of results suggested that animals fed at maintenance energy level would still deposit protein at the expense of body lipid. It is argued that this finding requires nonbiological efficiencies of lipid catabolism and protein synthesis and illustrates the limitation of the maintenance concept for growing animals. The multivariate analysis method proposed here circumvents many of the problems associated with the factorial regression analysis of ME intake on PD and LD. The method can be used to further refine nutritional models describing growth in pigs. 相似文献
19.
Impact of dietary tryptophan and behavioral type on growth performance and plasma amino acids of young pigs 总被引：8，自引：0，他引：8
B Sève M C Meunier-Salaün M Monnier Y Colléaux Y Henry 《Journal of animal science》1991,69(9):3679-3688
Tryptophan (TRP) content in the protein of the weaning diet was varied from deficient (.70 g/16 g N) to adequate (1.15 g/16 g N) and excess (1.60 g/16 g N) in diets fed to 108 pigs from d 5 to d 26 after weaning (W) and in 72 pigs from d 26 after weaning to slaughter (100 kg live weight) to assess immediate and long-term effects of TRP on performance. Daily weight gain and feed efficiency were improved when dietary TRP was increased from deficient to adequate (+60 and +40%, respectively). Concurrently, daily feed intake was elevated moderately (+15%). No further improvement was observed with excess TRP. In the low TRP group, gain/feed was significantly poorer up to 25 kg live weight, but this effect did not continue later. Although no compensatory growth could be shown in the group fed the deficient diet, growth retardation was very small (1.5%; P greater than .10) at slaughter. Early changes in TRP supply did not affect either carcass or meat quality. Behavioral reactivity, as determined on day W + 5 in an "open-field" test, did not affect early performance, but growth rate during the growing-finishing stage (3.2%) or the whole period (2.5%) was greater by nonemotional than by emotional pigs. Plasma amino acid contents in blood samples, withdrawn on day W + 15 (fed state) and W + 17 (fasted state), were consistent with the effect of TRP on growth rates. However, in the fasted state, a diet x reactivity interaction suggested that TRP removal from the plasma was less rapid in nonemotional than in emotional pigs. Furthermore, increased plasma concentrations of essential amino acids and urea in the latter group suggested that protein and amino acid catabolism was more rapid in emotional than in nonemotional pigs. These data are discussed relative to the effect of the behavioral type of pig on its TRP requirement. 相似文献
20.
Studies of the apparent and true ileal digestibility of crude protein and the apparent and true amino acid (AA) absorption were carried out with 7 female pigs in the live weight range between 22 and 34 kg after ileorectostomy. Protein sources of varied quality with regard to the method of treatment (toasted) and untoasted soybean oilmeal) and to the AA composition (vital gluten or vital gluten + L-lysine X HCl) were used. Distinct differences regarding the apparent ileal digestibility of crude protein and the apparent absorption of amino acids were discovered between the protein sources, the cause of which is to be seen in the different amounts of endogenous N. The true ileal digestibility of crude protein and amino acid absorption were partly distinctly higher than the values of the apparent ileal digestibility of crude protein and AA absorption. On the whole one can say that the results of the investigation gained by means of ileorectostomy can be compared to the values gained from cannulated animals. Thus the experimental method used is suitable for studying the absorption process to the end of the small intestine of pigs. 相似文献