日粮添加稀土壳糖胺降低蛋白水平对小鼠生长的影响

研究在日粮中添加0.05％稀土壳糖胺条件下,降低日粮蛋白水平对小鼠生长性能的影响.试验选用60只小鼠,随机分为3组,每组5个重复,每重复4只,各组间平均初始体重差异不显著.试验Ⅰ组(对照组)饲喂基础日粮(含20％粗蛋白质),试验Ⅱ组在基础日粮中添加0.05％稀土壳糖胺,试验Ⅲ组饲喂低蛋白日粮(含18％粗蛋白质),添加0.05％稀土壳糖胺.结果表明:试验Ⅲ组与对照组相比,小鼠的平均采食量无显著差异,平均增重极显著高于对照组,料重比差异不显著;与试验Ⅱ组相比,小鼠的平均采食量显著增加,平均增重无显著差异,料重比极显著提高.本试验条件下稀土壳糖胺适宜的添加水平为0.05％.     

丁酸钠对肉仔鸡生产性能及免疫功能的影响

试验选择体重基本一致的健康AA肉仔鸡300羽,随机分成5组:Ⅰ组(对照组)、Ⅱ组(250mg/kg丁酸钠)、Ⅲ组(500 mg/kg丁酸钠)、Ⅳ组(1 000 mg/kg丁酸钠)、Ⅴ组(40 mg/kg杆菌肽),每组6个重复,每个重复10羽,试验期21 d.试验结果表明:(1)14日龄采食量、增重、体重显著高于对照组(P<0.05),21日龄有增加趋势;14日龄料重比显著降低(P<0.05),21日龄有降低趋势.(2)14日龄和21日龄脾脏指数、胸腺指数、法氏囊指数有提高的趋势.(3)14日龄十二指肠上皮内淋巴细胞(IEL)数量显著高于对照组(P<0.05);21日龄十二指肠、空肠、回肠IEL数量均显著高于对照组(P<0.05).(4)14日龄十二指肠及回肠杯状细胞(GC)数量均显著高于对照组(P<0.05);21日龄空肠及回肠GC数量显著高于对照组(P<0.05).     

益生素对肉鸡免疫器官指数及血液生化指标的影响

探讨发霉日粮添加益生素对内鸡免疫器官指数及血液生化指标的影响.结果表明:在7～21日龄时,益生素组肉鸡血液中谷丙转氨酶活性、谷草转氨酶活性和料重比与发霉组相比,降低显著(P<0.05);与对照组相比,肉鸡血液中性粒细胞数降低显著(P<0.05),浆细胞数提高显著(P<0.05).在22～42日龄时,益生素组肉鸡血液中淋巴细胞数显著高于对照组及发霉组(P<0.05);法氏囊指数与发霉组相比提高显著(P<0.05).     

不同水平纳米蒙脱石对断奶仔猪生产性能的影响

研究不同水平纳米蒙脱石对断奶仔猪生产性能的影响,结果表明:添加纳米蒙脱石能降低断奶仔猪的腹泻频率和腹泻指数,Ⅰ、Ⅱ、Ⅲ组的腹泻频率比对照组分别降低了80.2%、215.1%和372.7%;腹泻指数比对照组分别降低了69.5%、218.3%和392.5%.试验前期,Ⅲ组的平均日采食量比对照组提高12.4%(P＜0.05),说明在日粮中添加纳米蒙脱石可减少断奶仔猪腹泻情况的发生,且表现为剂量依赖性,高水平添加还可以提高断奶仔猪平均日采食量.     

壳聚糖硒对肉仔鸡免疫功能及抗氧化作用的影响

探讨壳聚糖硒对肉仔鸡免疫功能及抗氧化作用的影响.选用1日龄AA肉仔鸡,对照组饲喂基础日粮,试验Ⅰ、Ⅱ、Ⅲ和Ⅳ组在基础日粮中分别添加0.01％、0.05％、0.1％和0.2％壳聚糖硒.结果表明:与对照组相比,Ⅰ、Ⅱ、Ⅲ和Ⅳ组肉仔鸡胸腺指数、脾脏指数、法氏囊指数、T淋巴细胞阳性率及新城疫抗体效价均有不同程度提高;壳聚糖硒能提高血清中超氧化物歧化酶和谷胱甘肽过氧化物酶的活性,降低丙二醛含量;本试验壳聚糖硒的添加剂量以0.1％～0.2％为宜.     

N-氨甲酰谷氨酸对70～98日龄桂黄兔生长性能及血清生化指标的影响

探讨N-氨甲酰谷氨酸对桂黄兔生长性能及血清生化指标的影响。试验选取36只平均体重(1 650±50)g的63日龄桂黄兔,对照组和试验Ⅰ、Ⅱ组桂黄兔每天分别口服N-氨甲酰谷氨酸0、300和600 mg/(kg体重)。结果表明：N-氨甲酰谷氨酸对70～98日龄桂黄兔平均日增重、平均日采食量和料重比的影响均不显著;对桂黄兔血清总胆固醇及白蛋白浓度影响也均不显著,但试验组较对照组有所提高;对血清甘油三酯及血清尿素氮含量影响显著。随着N-氨甲酰谷氨酸添加水平的提高,血清总蛋白浓度提高,试验Ⅱ组显著高于对照组及试验Ⅰ组;血清尿素氮浓度提高,试验组与对照组相比差异显著;血清甘油三酯浓度提高,试验Ⅱ组显著高于对照组。70～98日龄桂黄兔不需额外补充N-氨甲酰谷氨酸。     

不同组合全价颗粒饲料对育肥海南黑山羊生产性能的影响

选取初始体重（22.80±9.06）kg、遗传背景相近的海南黑山羊45只,随机分为3个处理组,分别饲喂菌草+精料（对照组）、全价颗粒饲料Ⅰ（试验Ⅰ组）和Ⅱ（试验Ⅱ组）,研究不同组合全价颗粒饲料对育肥海南黑山羊生产性能的影响。试验持续45 d。结果表明：试验Ⅰ组末重和平均日增重均显著高于对照组和试验Ⅱ组,试验Ⅱ组末重和平均日增重也都高于对照组,但差异不显著;试验Ⅰ组平均日采食量显著高于试验Ⅱ组,但与对照组间差异不显著;试验Ⅰ组料重比显著低于对照组和试验Ⅱ组,试验Ⅱ组料重比也显著低于对照组;试验Ⅰ组饲料增重成本低于对照组和试验Ⅱ组,而试验Ⅰ组的毛利润显著高于对照组和试验Ⅱ组。综合认为,全价颗粒饲料Ⅰ即苜蓿草粉＋玉米＋豆粕＋麸皮型育肥效果最佳。     

莫能菌素对肉牛生产性能和血液指标的影响

为研究莫能菌素饲喂肉牛后对生产性能和血液指标的影响,选用12月龄左右的西门塔尔牛48头,随机分为4组,对照组饲喂基础饲粮（混合精料+玉米秸秆;精、粗比45︰55）,处理Ⅰ、Ⅱ和Ⅲ组在基础日粮基础上分别添加100、200和300 mg/d的莫能菌素。结果表明,处理Ⅱ组玉米秸秆和总干物质采食量显著高于对照组;处理Ⅱ、Ⅲ组平均日增重显著高于对照组,料重比显著低于对照组和处理Ⅰ组,血糖、白蛋白、总蛋白、尿素氮、谷草转氨酶浓度以及增重收入、毛收益均显著高于对照组和处理Ⅰ组。莫能菌素的适宜添加量为200 mg/d。     

益生素对生长猪生产性能和免疫功能的影响

研究在生长猪日粮中添加益生素替代抗生素的可行性以及最佳用量.在对照组基础日粮中添加抗生素,在试验Ⅰ组、Ⅱ组和Ⅲ组日粮中分别添加0.1％、0.2％和0.4％益生素替代抗生素.结果表明:(1)与对照组相比,试验Ⅰ组、Ⅱ组和Ⅲ组平均日增重分别提高-9.80％ (P＜0.05)、0.81％ (P＞0.05)和1.35％ (P＞...     

大蒜素对肉仔鸡生长性能及抗氧化能力的影响

探讨大蒜素对AA肉仔鸡生长性能及抗氧化能力的影响.对照组饲喂基础日粮,试验组在日粮中分别添加200、400和600 mg/kg的大蒜素.结果表明:在21、42日龄时,添加400、600mg/kg的大蒜素组与对照组比,平均日采食量和平均日增重增加显著,料肉比下降显著;丙二醛含量下降显著;谷胱甘肽过氧化物酶和超氧化物歧化酶的活力显著上升,21日龄时过氧化氢酶活力上升显著,42日龄时过氧化氢酶活力无显著性变化.     

预混合饲料对肥育猪增重和肉品质影响的研究

以湖北省农业科学院试验种猪场的 5 4头“大长”仔猪为试验动物 ,随机分为 3个组 ,即Ⅰ、Ⅱ和Ⅲ组 ,进行 3个阶段 10 5d的饲养对比试验。在试验基础日粮中按 4%分别添加不同来源的猪用预混合饲料饲喂试验动物 ,观察其增重效果和肉品质。试验结果 ,试验全期Ⅰ、Ⅱ和Ⅲ组的平均日增重依次分别为 75 9,75 0和 746g ,差异不显著 (P>0 .0 1) ;平均料肉比依次分别为 3.19,3.15和 3.19,差异不显著 (P >0 .0 1) ;胴体质量和肉品质很一致 ;但增重 1kg耗预混合料成本依次分别为 0 .6 4,0 .75和 0 .74元 ,Ⅰ组比Ⅱ组和Ⅲ组分别降低 17.2 %和 15 .6 % ,差异极显著 (P <0 .0 1)。结果表明 ,3个组饲喂效果一致 ,且都达到较好水平 ,但以成本计 ,则显示Ⅰ组预混料为优     

Increased super-conditioning temperature of corn grain affects performance,skeletal growth,and blood metabolites in Holstein dairy calves

We aimed to evaluate the effects of feeding super-conditioned corn at different temperatures on intake, growth performance, total-tract starch digestibility, rumen fermentation, blood metabolites, and feeding behavior of dairy calves. Thirty-six Holstein female dairy calves (40 ± 1.72 kg of body weight, ± SD) were randomly assigned to 1 of the following 3 treatments: (1) ground corn (control; CON; n = 12), (2) corn super-conditioned at 75°C (T-75; n = 12), and (3) corn super-conditioned at 95°C (T-95; n = 12). Three mash starter feeds with an identical nutritional composition were blended with 5% chopped alfalfa hay and fed to individually-housed calves from d 3 to 77 of their birth. All calves were fed 4 L/d of pasteurized whole milk twice daily since d 3 to 56, followed by 2 L/d of morning feeding from d 57 to 63 of age. Calves were weaned on d 63 and remained in the study until d 77. The T-75 and T-95 diets increased total-tract starch digestibility compared with the CON diet. Dry matter intake and weaning or final BW were not affected by treatments; however, average daily gain and feed efficiency increased in calves fed T-95 in the overall period. The T-95 diet increased withers height and tended to increase hip height compared with other diets, but feeding behavior did not change throughout the experimental period. Ruminal pH decreased in calves fed the T-95 diet compared with T-75 and CON diets. The molar proportion of ruminal propionate increased, whereas the acetate-to-propionate ratio tended to decrease in calves fed the T-95 compared with CON diet. Calves fed the T-95 diet had the highest blood glucose concentration, whereas a trend for increased insulin concentration was observed in calves fed T-95 compared with other diets. In conclusion, super-conditioning temperature of corn (T-95 vs. T-75 and CON) improved the average daily gain, feed efficiency, and skeletal growth, but did not influence dry matter intake during the first 77 d of age. Finally, the total-tract starch digestibility increased, whereas ruminal pH dropped during the postweaning period as super-conditioning temperature elevated.     

Effects of feeding prepubertal heifers a high-energy diet for three, six, or twelve weeks on feed intake, body growth, and fat deposition

The objective was to determine the effects of feeding prepubertal dairy heifers a high-energy diet for a duration of 0, 3, 6, or 12 wk on feed intake, growth, and fat deposition. We also used feed composition, daily intake, and body growth data to evaluate the nutritional model of the 2001 National Research Council (NRC) Nutrient Requirements of Dairy Cattle. Holstein heifers (age = 11 wk; body weight = 107 ± 1 kg) were assigned to 1 of 4 treatments (n = 16/treatment) designated H0, H3, H6, and H12 and fed a low-energy diet for 12, 9, 6, or 0 wk, followed by a high-energy diet for 0, 3, 6, or 12 wk, respectively. Four heifers were killed initially (11 wk of age) and 64 heifers were killed at the end of the treatment period (23 wk of age). The low-energy diet was formulated to achieve 0.6 kg of average daily gain and contained 16% crude protein, and 45% neutral detergent fiber. The high-energy diet was formulated to achieve an average daily gain of 1.2 kg and contained 18% crude protein and 23% neutral detergent fiber. Actual daily gains averaged over the 12-wk treatment period were 0.64, 0.65, 0.83, and 1.09 kg for the H0, H3, H6, and H12 groups, respectively. Body weight, withers height, hip width, carcass weight, liver weight, and perirenal fat increased in heifers fed a high-energy diet for a longer duration. In addition, percentage of fat increased and percentage of protein decreased in rib sections with a longer duration on the high-energy diet. Uterine and ovarian weights adjusted for body weight decreased when heifers were fed the high-energy diet for a longer duration. The 2001 NRC underestimated dry matter intake of the high-energy diet and overestimated dry matter intake of the low-energy diet. On the basis of actual intakes of each diet, the NRC slightly underestimated gain for the low-energy diet and overestimated gain by 40% for the high-energy diet. The likely explanation for this is that the NRC underestimated the proportion of gain that was fat in the heifers fed the high-energy diet and therefore predicted more body gain per unit of energy intake. We concluded that feeding a high-energy diet for a short duration altered body growth and fat deposition in a time-dependent, linear manner consistent with feeding a high-energy diet for a long duration.     

Effects of feeding milk replacer at a moderate rate,ad libitum,or with a step-up program on Holstein calf growth performance to 4 months of age

The objective of this study was to evaluate 3 milk replacer (MR) feeding programs on calf performance to 4 mo of age. Male Holstein calves (n = 48; 2–3 d old) were randomly assigned to either a moderate rate of MR (MOD; 0.66 kg/d for 39 d, then 0.33 kg/d for 3 d), an ad libitum rate of MR (ADLIB; offered twice daily between 0630 and 0830 h and between 1430 and 1630 h for 35 d, 0.66 kg/d for 4 d, and 0.33 kg/d for 3 d), or a step-up rate of MR (STEPUP; increased from 0.32 to 0.62 kg/d in first 12 d, 0.66 kg/d for 27 d, and 0.33 kg/d for 3 d). The MR (25% CP, 18% fat) was fed twice daily to d 39 and once daily thereafter. During the nursery phase (0–56 d), calves were housed in individual pens and offered textured starter (40% starch, 21% CP on a DM basis) and water ad libitum. Calf body weight (BW) was measured initially and weekly thereafter. Hip widths (HW) were measured initially and every 2 wk thereafter. In the grower phase, (57–112 d), calves were grouped by previous treatment and moved to group pens (4 calves/pen). The same starter used in the nursery phase was blended with 5% chopped grass hay and offered ad libitum. Calf BW and HW were measured on d 56, 84, and 112. Total MR intake per calf averaged 27, 51, and 25 kg for MOD, ADLIB, and STEPUP programs, respectively, with a range of 42 to 63 kg for ADLIB. In the nursery phase, starter intake and feed efficiency were less for ADLIB versus MOD, whereas fecal scores and abnormal fecal score days were greater for calves fed ADLIB versus MOD. Calves fed STEPUP had lesser average daily gain than calves fed MOD. During the grower phase, initial BW was greater for ADLIB versus MOD, though final BW was not different between MOD and ADLIB or STEPUP. Calves previously fed MOD had greater average daily gain, feed efficiency, and HW change than calves fed ADLIB. In this study, feed efficiency was lower when MR was fed ad libitum, and growth advantages observed at 2 mo were lost by 4 mo of age.     

亚麻籽和茶多酚对肉鸭生长性能、屠宰性能、血液抗氧化能力和肌肉不饱和脂肪酸含量的影响

研究以亚麻籽为n-3 PUFA来源的肉鸭饲粮中添加茶多酚(TP),对其生长性能、屠宰性能、抗氧化能力和肌肉不饱和脂肪酸含量的影响。选用240只1日龄樱桃谷肉鸭,随机分为4组,其中对照组饲喂基础饲粮,实验组一、二、三分别饲喂含3%亚麻籽、3%亚麻籽+100 mg/kg TP、3%亚麻籽+200 mg/kg TP的实验饲粮。实验期为40d。结果表明:实验组一的平均日采食量(ADFI)和料重比(F/G)显著高于对照组(P 0.05);实验组二、三的ADFI和F/G与对照组差异不显著(P 0. 05)。屠宰率、半净膛率和全净膛率各组间均差异不显著(P 0. 05)。实验组三血浆的总抗氧化能力(T-AOC)、总超氧化物歧化酶(T-SOD)活力显著高于对照组(P 0. 01),丙二醛(MDA)含量显著低于对照组(P 0. 01)。各实验组腿肌中n-3 PUFA的含量均显著高于对照组(P 0. 05)。因此,饲粮中添加3%亚麻籽会显著增加樱桃谷肉鸭的料重比,以及肌肉中n-3PUFA的含量,但对屠宰性能无显著影响。在肉鸭饲粮中添加3%亚麻籽用于生产富含n-3 PUFA肉产品时加入200 mg/kg TP对肉鸭生长性能及机体抗氧化效果最佳。     

豌豆在生长猪日粮中应用效果的研究

试验选用 96头体重为 18.9± 2 .5kg的三元杂交 (北京黑×长白×杜洛克 )生长猪 ,随机分为 3个处理 ,处理1为玉米 -豆粕对照组 ;处理 2为用豌豆蛋白取代 2 5 %的基础日粮蛋白组 ;处理 3为用豌豆蛋白取代 5 0 %的基础日粮蛋白组。每个处理 8个重复 ,每个重复 4头猪 ,测定生长猪的生长性能。结果表明 ,试验前期用豌豆蛋白取代基础日粮的部分蛋白 ,可使生长猪的日增重和采食量均显著降低 (P <0 .0 5 ) ,而饲料增重比无明显变化。随着生长猪日龄增加 ,豌豆对其生长性能的影响逐渐减小     

Effects of feeding intensity and time on feed on performance, carcass characteristics and meat quality of Simmental bulls

Seventy two Simmental bulls, weighing 489 kg and approximately 15 months old fed extensively or intensively on maize silage and concentrate mixture for 100 or 138 days, were divided into four groups to assess the effect of time on feed and feeding intensity on the performance, carcass and meat quality traits. Bulls intensively fed for 138 days before slaughter had higher final body weight (673.7 kg) compared with the other three groups (610.6 kg, as overall mean). Intensive feeding significantly increased the average daily gain (1371 g/day) and improved the feed efficiency (6.95 kg DM/kg gain) compared with extensive feeding (943 g/day and 7.97 kg DM/kg gain). No significant differences were detected by time on feed. Hot carcass and kidney fat weights were significantly higher for intensively fed bulls compared with extensive ones. Dressing percentage significantly increased for 138 day groups compared with 100 day groups. Carcass conformation and fatness scores significantly improved by intensive feeding. L and b(*) values were not affected by time on feed or feeding intensity. Slaughtering after 138 days on feed significantly elevated the meat redness value (a(*)). Intensive feeding significantly decreased moisture and increased fat content of the longissimus dorsi muscle. Shear force, collagen content, juiciness, flavour and sarcomere length did not differ by time on feed or feeding intensity, while inconsistent effects were observed on tenderness and solubility of collagen.     

甜菜碱在肉鸡体内供甲基代谢及其节约蛋氨酸效应机制

选用 4 5 0羽 2 2日龄艾维茵肉鸡 ,按饲养试验要求分成 3组 (每组 3个重复 ) ,分别设为不添加蛋氨酸的对照组和添加 10 0 0mg/kg蛋氨酸的对照组 ,另一组则为添加 5 0 0mg/kg甜菜碱的试验组 ,进行了为期 2 1d的饲养试验。结果表明 :与不添加蛋氨酸组比 ,添加甜菜碱显著提高了肉鸡的日增重 (P <0 .0 5 ) ,降低了料重比(P <0 .0 5 ) ,达到了添加蛋氨酸的效果 (P >0 .0 5 ) ;添加甜菜碱导致了试验鸡肝脏甜菜碱 -高半胱氨酸S -甲基转移酶 (BHMT)活性升高 ,BHMT活性比不添加蛋氨酸组和添加蛋氨酸组均显著增高 (P <0 .0 1) ;与不添加蛋氨酸组比 ,添加甜菜碱还使肝脏甲基化反应产物 (游离肉碱和肌酸 )的生成量明显增多 (P <0 .0 1)和胸肌中两者的存储量显著增加 (P <0 .0 1) ,但与添加蛋氨酸组比无明显差异 (P >0 .0 5 )。上述结果提示 :甜菜碱在肝脏BHMT调控下 ,替代蛋氨酸为机体甲基化产物的合成提供甲基 ,从而产生节约蛋氨酸的效应。     

Rice protein concentrate partially replaces dried whey in the diet for early‐weaned piglets and improves their growth performance

BACKGROUND: Recently, rice protein concentrate (RPC), a much cheaper source of dietary protein, has become commercially available for use in the feed industry. Importantly, dietary supplementation with RPC can increase feed intake by early‐weaned pigs. The objective of this study was to determine whether RPC can replace milk protein in the diet for early‐weaned pigs. RESULTS: Neither average daily gain (ADG), average daily feed intake (ADFI), nor the feed/gain ratio differed among the treatment groups in weeks 1 and 2. In week 3, the addition of 5 or 10% RPC to diets increased (P < 0.05) ADFI and ADG of pigs compared to those in the control group fed a 60% dried whey diet. During the entire 21‐day trial, ADFI and ADG were greater (P < 0.05) in pigs fed the 5 and 10% RCP diets than in pigs fed the 60% dried whey and 15% RCP diets. There were no differences in the serum concentrations of growth hormone on days 14 and 21, serum concentrations of insulin growth factor‐I (IGF‐I) on day 14, or IGF‐I gene expression in liver and skeletal muscle on days 14 and 21 among the dietary treatments. Serum concentrations of IGF‐I in pigs fed the 5, 10 and 15% RPC diets were greater than those in pigs fed the 60% dried whey diet. CONCLUSION: Findings indicate that up to 10% RPC can be used to replace dried whey in the diet for 7‐ to 21‐day‐old weaned piglets and can improve their growth performance. Copyright © 2008 Society of Chemical Industry     

发酵非常规蛋白饲料对肉仔鸡生长性能和养分消化率的影响

研究了发酵非常规蛋白饲料(后称发酵饲料)对肉仔鸡生产性能和养分消化率的影响,选用250只肉仔鸡,随机分为5个处理组,试验期6周。A组饲料为基础玉米豆粕日粮,B组添加10%未发酵饲料替代部分豆粕,处理组C、D、E分别添加发酵饲料5%、10%、15%替代部分豆粕。处理组平均日采食量、平均日增重均高于B组,与A组相比差异不显著(P>0.05),D组与A组最为接近。通过代谢试验可得出,发酵饲料与未发酵饲料相比粗蛋白质消化率显著增加(P<0.05),氨基酸消化率差异不显著(P>0.05)。因此,在发酵饲料替代10%豆粕是可行的。