不同蛋白质水平代乳品对羔羊生长性能的影响

代乳品蛋白质由膨化大豆粉、奶粉、玉米蛋白粉等组成,其水平按一定梯度设计,组成1号、2号、3号、4号四种饲粮。饲养试验选用陶赛特×小尾寒羊F1代的初生公、母羔羊各25只,随机分成5组,每组10只(5♂+5♀),Ⅰ组～Ⅳ组分别饲喂1号～4号代乳品,第Ⅴ组为对照组,自然哺乳。试验结果表明:代乳品蛋白质水平较高者,更有利于羔羊体尺的增加,第Ⅳ组羔羊体高、体长指标和平均日增重好于其它各试验组,但略逊于对照组。     

Effects of wheat protein in milk replacers on abomasal emptying rate in calves

Diarrhoea is a condition with tremendous impact on calf health. Infectious agents play a dominant role; however, non‐infective factors may also contribute to pathogenesis of diarrhoea. One factor, the abomasal emptying rate, is mainly influenced by the composition of feed. The aim of the study was to assess the influence of different protein sources in milk replacers on abomasal emptying rate and clinical parameters. The effect of increasing age of the calves on abomasal emptying was also evaluated. The study compared abomasal emptying rates and clinical parameters in calves, which were fed either milk replacer containing only whey protein or one which partially contained wheat protein. Abomasal emptying rate was estimated by ultrasonography. Ten calves were used in the study over 18 days, and each calf was fed 3 periods of 3 days length using different milk replacers in an alternating crossover design. The abomasum was emptied significantly faster when the wheat protein containing milk replacer was fed (half‐emptying time wheat protein 49.1 ± 4.1 min, half‐emptying time milk protein 59.1 ± 7.4 min); however, clinical parameters and weight gain did not differ between the feeding regimes. Age did not significantly influence abomasal emptying rate. As milk replacers containing wheat proteins increased abomasal emptying rate, they may have a higher potential to initiate diarrhoea, especially if high volumes are fed. Thus, the feeding regimes are likely to be even more important when such milk replacers are used.     

Effect of protein : energy ratio in milk replacers on growth performance of goat kids

Two separate experiments were carried out to establish the effects of the protein:energy ratio in milk replacers on growth performance, plasma lipid concentrations and fatty acid composition in adipose tissue of male goat kids. In the first experiment there were 211 3-day- old goat kids and in the second experiment there were 121 kids aged 3-7 days. The animals were fed ad libitum for a period of 4 weeks on milk replacers containing either 11.5 or 9.5 g crude protein/MJ metabolizable energy. In essence, protein was exchanged with fat on a weight basis. Milk concentrations were increased from 160 to 190 g/l in experiment 1, from 150 to 180 g/l in experiment 2. There were significant increases in body weight and feed intake when the milk replacer with high protein : energy ratio was fed. Group mean average daily weight gain was 168 and 203 g for the groups with low and high dietary protein:energy ratio in experiment 1; for experiment 2 the values were 139 and 160 g. Average dry matter intake was 18 and 14% higher for the diet with high protein:energy ratio in experiments 1 and 2, respectively. There was no change in either feed conversion (feed:gain ratio) or energy conversion (weight gain:energy intake ratio). There were no consistent diet effects on plasma lipid concentrations. Dietary fatty acid composition was reflected by that of adipose tissue. The milk replacer with high protein:energy ratio produced a small increase in the contents of myristic and palmitic acid in adipose tissue.     

大豆蛋白在犊牛代乳料中的应用研究进展

随着人们生活水平的不断提高 ,乳制品加工业的不断兴起 ,对牛奶的需求量越来越大。如果能用营养全面、犊牛能消化吸收、成本又低的代乳料代替部分或全部牛奶 ,就能大大减少犊牛用奶 ,为乳制品加工提供更多的奶源。因此 ,研制成本低又能满足犊牛营养需要的与牛奶近似的饲用代乳料 ,已成为研究者们关注的课题。大豆蛋白以其价廉及蛋白质含量高而成为犊牛代乳料研究的主要蛋白来源。1　代乳料的发展2 0世纪 60年代 ,欧美一些国家开始使用代乳料 ,由于当时脱脂乳蛋白过剩 ,价格较低 ,因而在代乳料中几乎全部使用脱脂乳蛋白作蛋白源。到 80年代 ,…     

代乳粉在早期断奶仔猪中的研究与应用

选取28日龄断奶的杜×长×大三元商品仔猪90头,按体重接近的原则分成试验组和对照组,每组3个重复,每个重复15头。对照组仅提供教槽料,试验组在教槽料的基础上饮喂冲调代乳粉10d,在停止喂给代乳液后,又进行了为期15d的后续效果测定。通过测定仔猪的生长性能和观察仔猪行为来研究代乳粉在减缓仔猪断奶应激方面的效果。结果表明:在断奶后10d测得的平均日增重,试验组比对照组提高16.2%,试验组料重比比对照组下降显著(P<0.05),腹泻程度也显著降低,仔猪行为表现比较安静,说明在断奶后补饮代乳液可在一定程度上缓解断奶应激。     

Associations between maternal milk protein genotypes with preweaning calf growth traits in beef cattle

The objectives of this study were to investigate milk casein polymorphisms in dams and to determine the impacts of maternal casein genotypes on growth traits of their sucking calves. Milk samples from 433 dams of the breeds German Angus (GA) and German Simmental (GS) were typed at the milk protein loci α _s1-casein (α_s1-CN), β-casein (β-CN), α _s2-casein (α_s2-CN), and κ-casein (κ-CN) via isoelectric focusing. Associations between casein genotypes in maternal milk with growth traits of their 1,872 calves were analyzed until the age of weaning using linear mixed models, considering either genotypes of individual casein loci (model 1) or composite α _s1-β-α _s2-κ-CN genotypes within the casein cluster (model 2). Besides environmental effects such as sex, age of the dam, and calving year-season, genetic effects (breed group and maternal and paternal effects) were considered in statistical models. The composite casein genotype BBǀA2A2ǀAAǀAB (order of genes on bovine chromosome 6: α _s1-ǀβ-ǀα _s2-ǀκ-CN) was associated with greater average daily weight gains (ADG) and heavier age-adjusted weaning weights (WW) of calves (P < 0.05). The effects of composite genotypes on birth weight of calves were similar (P > 0.05; model 2). With regard to individual casein loci, greater ADG and WW were observed for calves from dams with the genotypes κ-CN BB and α _s1-CN BB, respectively (P < 0.05; model 1). Age-adjusted WW was largest for calves from dams carrying the κ-CN genotype BB (215 kg) compared with calves representing the maternal AB and AA genotypes (both 204 kg). Results from the present study suggested selectable casein genotypes due to their nutritional value of milk (value in terms of offspring performances), offering new perspectives for breeding strategies in beef cattle to improve preweaning calf performance.     

两种不同营养水平的代乳粉对羔羊生长性能的影响

试验选用18只10日龄公羔，随即分成A、B、C三组，A组哺喂1号（低营养水平）代乳粉，B组哺喂2号（高营养水平）代乳粉，C组随母羊自然哺乳，每隔10d测定一次体重、体尺，进行了60d的饲养试验，结果表明：30日龄前，特别是10～20日龄阶段，自然哺乳组日增重达到154g／d，而代乳粉组平均日增重仅仅76．9g／d，试验组与对照组差异极显著（P〈0．01）；20日龄时，A、B、C三组体高增加分别为2．4％、6．50％、7．36％，A、B两组分别与C组差异极显著（P〈0．01）；体长A、B两组与C组差异显著（P〈0．05）：但随着日龄的增加，消化道逐渐健全，羔羊越来越习惯于吸允代乳粉，消化吸收能力加强，尤其到试验后期（41—60d），B组表现明显的生长优势，不同日龄体重、阶段平均日增重、体高、体长、胸围、管围都明显高于A组和C组。     

犊牛代乳粉的研究进展

犊牛出生后,其生存环境由恒温过度到变温、由无菌过渡到有菌,营养物质由血液供给变为胃肠道消化供给。犊牛瘤胃功能尚未健全,鲜牛奶可以说是理想的饲料,我国大多数犊牛饲喂牛奶,犊牛自出生到断奶约需要消耗牛奶350～450kg/头。随着动物生理营养和消化生理的研究不断深入,对犊牛的消化代谢生理和营养需要有了更深的了解,犊牛的饲养方式发生了根本改变。世界各国对奶牛代乳粉开展了广泛的研究,用代乳粉饲喂犊牛已经成为现实,现代奶牛业的工厂化和集约化发展要求犊牛早期断奶并快速生长。Heinrichs(1995)报道,采用营养全面、易于消化吸收的代…     

The evaluation of the curd forming ability of milk replacers

Inadequate milk curd formation in the abomasum of newborn calves causes malnutrition and diarrhea. In order to define the factors of inadequate curd formation, we compared the curd forming ability among 9 kinds of milk replacers, bulk milk (raw milk), and skim milk both in vitro and in vivo . When rennet was added, the raw milk and one milk replacer formed firm curds. The rest of the milk replacers and skim milk did not form any curd. When a solution of HCl was added, raw milk, three milk replacers and skim milk formed the curd at pH 4.5, but the other milk replacers did not. When HCl was added following the rennet, raw milk, one milk replacer and skim milk formed the curd. In vivo , raw milk, two milk replacers and skim milk showed good curd formation whereas the other milk replacers showed poor curd formation inside the abomasums of the calves. This study showed that most of the milk replacers sold in Japan could not form the curd with rennet.     

不同配方代乳料对羔羊生长发育的影响

试验用3个不同配方的代乳料对羔羊进行早期断奶,研究其对羔羊体重、成活率、体尺等指标的影响.选择80只25日龄的无角陶赛特羔羊,随机分为4组进行试验.3个试验组5日龄内用代乳料逐渐代替母乳,另一组为对照组(自然哺乳).结果表明:①试验Ⅰ组、Ⅱ组、Ⅲ组的只均日增重分别为:223.25、256.67和257.25 g,高于对照组的159.29 g,差异显著(P<0.05);②试验组羔羊体高、尻高、胸围、体长均高于对照组,试验组间无明显差异;③试验组成活率为100%,比对照组95%有所提高;④试验组羔羊断奶时只均利润比对照组增加了40元以上.     

不同蛋白来源的代乳粉代替全乳饲喂犊牛的试验报告

试验是将16头8～12日龄的荷斯坦奶公犊随机分为3组,每组4头犊牛。A组饲喂以大豆浓缩蛋白为蛋白源的代乳粉,B组饲喂以大豆浓缩蛋白和玉米蛋白为蛋白源的代乳粉,C组饲喂牛奶。试验期为51d。试验结果表明,以大豆浓缩蛋白加玉米蛋白为蛋白源的代乳粉组的日增重优于其它2组,它们的日增重分别是:A组为450.98g,B组为579.74g,C组为510.29g。在试验期间,3组的犊牛的血清钙、磷、铁、总蛋白、血糖、尿素氮和甘油三酯的浓度无明显差异(P>0.05)。2组代乳粉组都比牛奶组饲养成本低,B组最低。     

Growth,nutrient utilization,and body composition of dairy calves fed milk replacers containing different amounts of protein

Male Holstein calves < 1 wk of age were allowed a 2-wk adaptation period after purchase, and then were blocked by BW and assigned randomly within block to either a baseline slaughter group or one of four experimental groups (n = 8 to 9 per group). Treatments were isocaloric milk replacers (12.5% solids) fed at 12% of BW that contained 16.1, 18.5, 22.9, or 25.8% CP (DM basis) from whey protein sources. After a 6-wk feeding period, all calves were slaughtered and the weights and chemical composition of the viscera-free carcasses (VFC; including head, hide, feet, and tail) were determined. Gain of BW (0.38, 0.45, 0.56, and 0.62 kg/d) and gain:feed ratio (0.51, 0.59, 0.71, and 0.78) increased linearly (P < 0.001) as dietary CP increased; rate of change in body length, wither height, and heart girth also increased linearly (P < or = 0.05). Balance measurements conducted during wk 3 and 4 of the experimental period showed that both absorbed N (16.9, 20.0, 25.8, and 30.6 g/d) and retained N (7.6, 9.0, 13.2, and 15.6 g/d) increased linearly (P < 0.001) as dietary CP increased. Retained N as a percentage of absorbed N increased linearly (P < 0.01) as dietary CP increased (44.3, 44.7, 50.7, and 50.9%), whereas biological value was unaffected (71.1, 68.7, 69.5, and 67.3%; P = 0.26). Digestible energy and ME represented 94.5 and 89.7% of intake energy, respectively, and were not affected by dietary CP content. Plasma urea N concentration increased linearly (2.9, 3.3, 4.6, and 6.0 mg/dL) as dietary CP increased. Contents of water (68.2, 69.1, 70.2, and 70.5%; P < 0.001) and protein (19.6, 20.0, 20.0, and 20.2%; P < 0.10) in VFC increased linearly, whereas contents of fat (7.2, 6.2, 5.5, and 5.2%; P < 0.001) and ash (5.1, 5.2, 4.8, and 4.7%; P < 0.02) decreased linearly as dietary CP increased. Trends in visceral tissue composition were similar to those for VFC. The content of water in VFC tissue gain increased, whereas contents of fat and energy decreased, as dietary CP increased. Final VFC energy and gain of energy in VFC were not affected by dietary CP. At similar initial ME intakes, increasing dietary CP (i.e., increasing protein: energy) linearly increased ADG, gain:feed, N retention, and deposition of lean tissue in VFC, demonstrating that diet composition can markedly affect components of body growth in preruminant dairy calves.     

Growth and body composition of dairy calves fed milk replacers containing different amounts of protein at two feeding rates

Previous research has demonstrated that increasing the CP concentration from 16 to 26% in milk replacers fed to male preruminant dairy calves at 1.5% of BW (DM basis) daily resulted in increased ADG, G:F, and deposition of lean tissue. However, the effects of dietary CP would be expected to vary depending on ME intake. Here, male Holstein calves < 1 wk old were used to determine the effects of feeding rate and CP concentration of isocaloric, whey protein-based milk replacers on growth and body composition. After a 2-wk standardization period, calves were assigned randomly to an initial baseline group or to treatments in a 2 x 4 factorial arrangement of feeding rate (1.25 or 1.75% of BW daily, DM basis) and milk replacer CP concentration (14, 18, 22, or 26% of DM). No starter was offered, but calves had free access to water. After a 5-wk feeding period, calves were slaughtered and body composition was determined. Increasing the feeding rate increased (P < 0.05) ADG, G:F, empty-body gains of chemical components and energy, the percentage of fat in empty BW gain and in the final empty body, and concentrations of IGF-I and insulin in plasma. Increasing the feeding rate decreased (P < 0.01) percentages of water and protein in the empty body and decreased urea N in plasma. Increasing dietary CP concentration linearly increased (P < 0.05) ADG, body length, heart girth, and gains of water and protein but linearly decreased (P < 0.05) fat gain. As dietary CP increased, fat content in empty body gain decreased, and water and protein increased. Increasing CP concentration increased (quadratic, P < 0.02) G:F, with greatest efficiencies for calves fed 22% CP. Gross energetic efficiency (retained energy:intake energy) was greater (P < 0.05) for calves fed at 1.75% of BW daily. Efficiency of dietary protein use for protein gain was greater for calves fed at 1.75% of BW daily but was not affected by dietary CP. The ratio of protein gain to apparently digestible protein intake above maintenance decreased as dietary CP increased. Interactions (P < 0.05) of feeding rate and CP concentration for gains of water and protein indicated that when dietary CP was 26% the ME supply limited protein use by calves fed at 1.25% of BW daily. Body composition of preruminant calves can be markedly altered by manipulating the protein to energy ratio in milk replacers. These dietary effects on body composition and growth are not predicted by current NRC standards.     

Composition and use of puppy milk replacers in German Shepherd puppies in the Netherlands

Enostosis or eosinophilic panosteitis is a common disease in young growing large-breed dogs, such as the German Shepherd, and the risk of developing the disease by 3-4 months of age is increased by a high calcium intake. The aim of the study was to investigate whether German Shepherd puppies raised on milk replacers receive more calcium and/or vitamin D than their requirements in the pre-weaning period and thus are at increased risk of developing skeletal diseases. To this end, we surveyed German Shepherd breeders in the Netherlands about the use of puppy milk replacers (PMR). The metabolizable energy, calcium, phosphorus and vitamin D content of the eight most used PMR were compared with that of bitch milk, as reported in the literature. The protein and fat content of most PMR were somewhat lower (range 24.4-33.2 g per 100 g on dmb and 18.3-37.5 g per 100 g on dmb respectively) compared with bitch milk (31.9 and 40.2 g on dmb respectively). The vitamin D content of one of the PMR samples was sevenfold the level recommended by the NRC (Nutrient Requirements of Dogs and Cats, National Academy Press, 2006) and threefold the average level of bitch milk. The clinical relevance of this high amount is questionable, as bitch milk contains mainly 25-hydroxy-vitamin D [3843 μg (96.1 IU) per 100 g on dmb] and only limited amounts of vitamin D [524 μg (13.3 IU) per 100 g on dmb], as was determined in this study. Dutch German Shepherd breeders tended to overfeed their puppies. We calculated that misguided use of PMR can increase the risk of excessive calcium, phosphorus and possibly vitamin D intake during a vulnerable period, potentially giving rise to bone and cartilage problems later in life.     

Immunologic responses against hydrolyzed soy protein in dogs with experimentally induced soy hypersensitivity

OBJECTIVE: To assess whether dogs with experimentally induced type I hypersensitivity against soy protein would respond to soy hydrolysate and develop cutaneous or gastrointestinal tract reactions after intradermal and oral challenge exposure. ANIMALS: 12 na?ve Beagle pups (9 sensitized and 3 control dogs). PROCEDURE: 9 dogs were sensitized against soy protein by administration of allergens during a 90-day period. After the sensitization period, serum concentrations of soy-specific IgE were determined and an intradermal test was performed to confirm the dogs were sensitized against soy protein. An intradermal challenge test and an oral challenge test with native and hydrolyzed soy protein were conducted on 6 sensitized and 2 control dogs. RESULTS: High serum concentrations of soy-specific IgE and positive results for the intradermal test were observed for the 9 sensitized dogs after completion of the sesitization process. Sensitized dogs challenge exposed with hydrolyzed soy protein had a reduced inflammatory response after intradermal injection and no clinical response after an oral challenge exposure, compared with responses after intradermal and oral challenge exposure with native soy protein. CONCLUSIONS AND CLINICAL RELEVANCE: Soy-sensitized dogs did not respond to oral administration of hydrolyzed soy protein. Thus, hydrolyzed soy protein may be useful in diets formulated for the management of dogs with adverse reactions to food.     

High intake of calcium formiate depresses macronutrient digestibility in veal calves fed milk replacers containing either dairy proteins or whey protein plus soya protein concentrate

A study to determine whether calcium intake and the type of dietary protein would show an interaction with regard to macronutrient digestibility in veal calves was carried out. Eighty four male calves, about 8 weeks of age, were fed four experimental milk replacers in a 2  2 factorial design. The diets contained either dairy protein as a sole source of protein or whey protein (76% of total protein) plus soya protein concentrate (24% of total protein) and either a low or high concentration of calcium. Calcium was added to the high-calcium diets in the form of calcium formiate. The concentration of calcium was on average 0.64% of air-dry matter in the low-calcium rations and 1.25% in the calcium-rich rations. After the experimental diets had been fed for 10 weeks, body-weight gain was significantly lower (on average 5.5 kg) in the calves that had been fed on the diets containing soya protein concentrate and whey protein. Calcium intake did not significantly influence weight gain. In the calves that were fed soya proteins, digestibility of protein and carbohydrates was significantly lower than in those fed dairy protein only, but fat digestion was unaffected. High calcium intake significantly reduced the digestibility of protein, fat and carbohydrates. With regard to carbohydrate digestibility there was an interaction between the amount of calcium and type of protein in the diet such that the effect of calcium was greater when the diet contained 24% of protein in the form of soya protein instead of dairy protein only.     

用代乳料培育奶公犊的效果探索

将12头犊牛随机分为2组,对照组喂给常乳,试验组喂给代乳料,通过60d饲养试验,研究代乳料对奶公犊的影响。结果表明:试验组与对照组牛60日龄平均体重分别为76.0、87.4kg;平均日增重分别为0.67、0.84kg。平均管围分别为11.6、12.0cm;平均体斜长分别为81.4、83.0cm;平均体高为85.6、87.9cm。经t检验,差异不显著(P>0.05)。试验组每头牛的饲料成本比对照组低34.7%,差异极显著(377:577元/头,P<0.01)。从而认为,用人工代乳料可以代替母乳培育奶公犊,且可显著降低生产成本。