早期断奶仔猪日粮中蛋氨酸、苏氨酸水平对机体蛋白质代谢的影响

试验采用早期断奶仔猪(26±1日龄,BW668±004kg)72头,按2×3因素水平设计,即两个蛋氨酸水平(029%,039%)和三个苏氨酸水平(060%,068%和076%)分为6种日粮处理.基础日粮为玉米-小麦-豆粕-花生粕型日粮,试验期为22d.试验结束时,各组选取2头仔猪进行屠宰,取肝脏及背最长肌,分析组织样品中蛋白质(Protein)、DNA和RNA含量,并计算Protein/RNA的比值,以研究蛋白质合成效率的变化.结果表明,日粮中苏氨酸的不同水平对肝脏中蛋白质水平有显著影响(P<0.05),日粮中不同水平蛋氨酸和苏氨酸对肝脏及背最长肌中DNA、RNA含量及蛋白质与RNA比值无影响.     

生长猪低蛋白质日粮可消化赖氨酸、蛋氨酸+胱氨酸、苏氨酸、色氨酸平衡模式的研究

试验通过研究低蛋白质饲粮中可消化赖氨酸、蛋氨酸 胱氨酸、苏氨酸和色氨酸水平对生长猪生产性能和尿素氮的影响,以建立生长猪日增重和料重比对日粮可消化氨基酸的回归模型.选取体重30 kg的三元(杜×长×大)杂交生长猪68头,随机分为17个处理,每个处理4头猪,运用4因素5水平二次回归正交组合设计(1/2实施),研究得出日增重和料重比对日粮可消化赖氨酸、蛋氨酸 胱氨酸、苏氨酸和色氨酸水平的回归方程.生长猪日增重(Y1,g)对日粮可消化赖氨酸(X1,%)、蛋氨酸 胱氨酸(X2,%)、苏氨酸(X2,%)和色氨酸(X4,%)水平的回归方程为:Y1=-5.568 0 7.587 8X1 3.045 2X2 9.183 5X3 4.226 9X4 5.200 4X1 X2-1.905 6X1X3 2.233 4X1X4-6.005X12-7.3694X22-7.5432X32-22.073242=(R2:0.964 0,P<0.05);生长猪料重比(Y2,g)对日粮可消化赖氨酸(X1,%)、蛋氨酸 胱氨酸(X2,%)、苏氨酸(X3,%)和色氨酸(X4,%)水平的回归方程为:Y2=12.176 0-9.843 6X1-19.043 2X2-2.486 7X3-11.733 0X4-1.875 0X1 X2-6.875 0X1 X3 1.562 5X1X4 8.986 6X12 23.274 5X22 7.968 4X32 33.470 5X42(R2=0.921 3,P<0.01);日增重达到最大值(0.775 kg)时,日粮的可消化赖氨酸、蛋氨酸 胱氨酸、苏氨酸和色氨酸水平分别为0.78%、0.48%、0.51%和0.14%.相应的氨基酸比例为Lys:(Met Cys):Thr:Trp=100:61:64:18.料重比最小(2.69)时,对应的日粮可消化赖氨酸、蛋氨酸 胱氨酸、苏氨酸和色氨酸水平分别为0.77%、0.44%、0.49%和0.16%.氨基酸比例为Lys:(Met Cys):Thr:Trp=100:57:64:21.对日增重和料重比进行综合考虑,获得最佳生产性能的可消化氨基酸的比例范围为Lys:(Met Cys):Thr:Trp=100:(57～61):64:(18～21).     

乌骨鸡日粮蛋氨酸、赖氨酸、苏氨酸需要量的研究

单因子试验设计,将1日龄丝毛乌骨鸡雏200只,随机分为10组,每组20只,逐只带翅号,研究0～12周龄乌骨鸡对日粮蛋氨酸、赖氨酸、苏氨酸的营养需要。以乌骨鸡生产性能和经济效益为判断依据,乌骨鸡几种氨基酸营养需要(%)为:0～4周龄蛋氨酸0.32,赖氨酸0.90,苏氨酸0.87;5～8周龄蛋氨酸0.29,赖氨酸0.77,苏氨酸0.78;9～12周龄蛋氨酸0.28,赖氨酸0.76,苏氨酸0.77。     

日粮蛋氨酸及赖氨酸水平对雌性肉仔鸡胴体组成的影响

本试验旨在探讨日粮蛋氨酸和赖氨酸水平对 3～ 6周龄艾维茵母鸡胴体组成及脂肪代谢的影响。试验采用 3× 5双因子试验设计 ,蛋氨酸设 3个水平 ( 0 32 % ,0 4 4% ,0 56 % ) ,赖氨酸设 5个水平( 0 7% ,0 85% ,1 0 % ,1 1 5% ,1 30 % ) ,一共形成 1 5个处理组。基础日粮由玉米、豆粕、花生粕、玉米蛋白粉等组成。含代谢能 1 2 73MJ/Kg ,粗蛋白 1 8 8% ,赖氨酸 0 7% ,蛋氨酸 0 32 %。试验末分别检测生产性能 ,屠宰性能及血液生化指标。结果表明 :日粮赖氨酸和蛋氨酸显著影响了肉仔鸡的胴体组成和脂肪代谢 (P <0 0 1 )。赖氨酸和蛋氨酸缺乏或过量 ,血浆尿酸、甘油三脂和极低密度脂蛋白浓度均呈上升趋势。日粮赖氨酸 ( 0 70 % )和蛋氨酸 ( 0 32 % )缺乏显著降低了肉仔鸡的体增重、胸肉率及全净膛率 (P<0 0 5) ,而腹脂沉积偏高。适度提高日粮赖氨酸和蛋氨酸水平可以提高全净膛率 ,胸肌率 ,降低腹脂沉积 ,从而改善胴体品质     

日粮蛋白质和氨基酸水平对生长猪阳离子氨基酸转运体选择性表达和血清氨基酸浓度的影响

亮氨酸有利于赖氨酸的吸收,但是没有报道表明粗蛋白质、赖氨酸和亮氨酸水平对于猪阳离子氨基酸转运体表达的影响.因此,本试验选用20头猪(初始体重为14.9 kg±0.62 kg)用于评价两种蛋白质水平及低蛋白质日粮中赖氨酸、苏氨酸、蛋氨酸及亮氨酸含量不同对于空肠中b0+和CAT-1 mRNA表达、背最长肌和半腱肌的影响.处理组如下:①小麦-豆粕日粮,20％粗蛋白质(对照组);②小麦日粮,其中缺乏赖氨酸、苏氨酸和蛋氨酸(基础日粮);③基础日粮中添加70％L-赖氨酸、0.27％L-苏氨酸、0.1％ DL-蛋氨酸(LTM日粮);④LTM日粮添加0.8％L-苏氨酸(LTM日粮+苏氨酸).除了基础日粮,其余日粮中的赖氨酸、苏氨酸和蛋氨酸含量均满足营养需要.LTM日粮+苏氨酸日粮提供超过60％的亮氨酸.LTM日粮中添加赖氨酸、苏氨酸和蛋氨酸提高了空肠中b0+及背最长肌和半腱肌中CAT-1的<表达,同时降低了空肠中CAT-1的表达;且血清中赖氨酸浓度增加(P＜0.01).继续添加L-亮氨酸(LTM日粮+亮氨酸)降低了空肠中b0+及背最长肌CAT-1的表达量,提高了血清中亮氨酸和精氨酸浓度,但降低了异亮氨酸浓度(P＜0.05).与饲喂LTM日粮组相比,饲喂对照组日粮的仔猪空肠中b0+表达量稍低,背最长肌和半腱肌中CAT-1表达量较高(P＜0.05),且血清中异亮氨酸、亮氨酸和缬氨酸浓度较低(P＜0.05),而赖氨酸的浓度较高(P＜0.01).以上结果表明,日粮氨基酸水平和来源均可影响饲喂小麦基础日粮猪体内阳离子氨基酸转运体的表达.     

乌骨鸡饲料氨基酸消化率及日粮蛋氨酸、赖氨酸营养需要的研究

试验研究了乌骨鸡对日粮中蛋氨酸、赖氨酸的营养需要和对日粮氨基酸的消化率。试验1采用单因子试验设计,研究0~12周龄乌骨鸡对日粮中蛋氨酸、赖氨酸的营养需要。结果表明,1)日粮中蛋氨酸水平:0~4周龄0.32%~0.52%,5~8周龄0.29%~0.49%,9~12周龄0.28%~0.48%;日粮中赖氨酸水平:0~4周龄0.90%~1.10%,5~8周龄0.77%~0.97%,9~12周龄0.76%~0.96%对乌骨鸡体质量、体增重、采食量和料重比均未产生显著影响。2)根据乌骨鸡生产性能和经济效益,建议各饲养阶段日粮真可消化蛋氨酸、赖氨酸营养水平为:0~4周龄蛋氨酸0.28%,赖氨酸0.81%;5~8周龄蛋氨酸0.25%,赖氨酸0.69%;9~12周龄蛋氨酸0.25%,赖氨酸0.69%。试验2选用成年乌骨公鸡进行代谢试验,测定了玉米、麸皮、豆粕、肉骨粉、菌糖蛋白等饲料氨基酸消化率,为乌骨鸡日粮的合理配制提供了科学依据。     

低蛋白质日粮中添加赖氨酸和蛋氨酸对生长前期蓝狐消化代谢及生产性能的影响

本试验旨在探讨降低日粮中蛋白质水平同时补充适当的限制性氨基酸对生长前期蓝狐消化代谢及生产性能的影响.随机选取75只8周龄健康公蓝狐,随机分成5组,每组15个重复,每个重复1只蓝狐.对照组日粮蛋白质水平为28.7%,试验组日粮初始蛋白质水平分别为27.4%(Ⅰ组)、24.5%(Ⅱ组)、23.2%(Ⅲ组)和22.4%(Ⅳ组),然后分别加入相应量的赖氨酸和蛋氨酸,使其水平与对照组相当.结果表明:与对照组相比,当日粮中蛋白质水平降到27.4%并加入相应量的赖氨酸和蛋氨酸,其终体重、日增重、氮沉积极显著升高(P<0.01),例料转化率、氮沉积率和氮生物学效价显著升高(P<0.05);当日粮中蛋白质水平降到23.2%并加入相应量的赖氨酸和蛋氨酸,蓝狐的消化代谢及生长性能的各项指标均差异不显著(P>0.05).综合各项试验指标,蓝狐生长前期日粮蛋白质水平降低1.0～1.5个百分点并添加相应量的赖氨酸和蛋氨酸,可显著提高监狐消化率、代谢率和生产性能;降低2.0～4.0个百分点并添加相应的赖氨酸和蛋氨酸,对蓝狐消化代谢及生产性能无显著影响;此外,添加限制性氨基酸的低蛋白质日粮降低了蓝狐的饲养成本,减少了氮排泄量.     

0～4周龄合浦肉鹅饲粮中赖氨酸、蛋氨酸和苏氨酸适宜水平的研究

本试验选取1日龄健康的合浦雏鹅270只,随机分成9组,每组3个重复,每个重复10只,公母鹅各一半,采用3×3三因素正交试验设计,来确定0～4周龄肉仔鹅赖氨酸、蛋氨酸和苏氨酸的需要量。日粮中赖氨酸、蛋氨酸和苏氨酸含量分别为：赖氨酸各个水平为：0．85％、1．00％、1．15％;蛋氨酸各个水平为：0．35％、0．45％、0．55％;苏氨酸各个水平为：0．55％、0．65％、0．75％。实验结果表明,不同的赖氨酸、蛋氨酸和苏氨酸水平,对鹅的生长性能和血清生化指标有显著影响（P〈0．05）。以增重和料重比为衡量指标,当日粮中赖氨酸含量为1．00％、蛋氨酸含量为0．45％、苏氨酸含量为0．55％时,合浦肉仔鹅生长性能最佳。     

日粮中不同蛋氨酸水平对感染E.tenella肉仔鸡的影响

试验采用 3× 2试验设计。将 7日龄 36 0只AA肉仔鸡按称重均匀分成 6组 (1、2、3、4、5、6 ) ,每组 6 0只鸡 ,每 5只鸡 1笼 ,饲养在不锈钢笼中。A处理为日粮蛋氨酸添加水平 0、0 .2 %、0 .8% ,B处理为孢子化柔嫩艾美耳球虫 (E .tenella)卵囊 (接种 3× 10 4 个孢子化E .tenella卵囊 ,未接种 )。其中 1、2组饲喂试粮 1(添加 0蛋氨酸 ) ,3、4组饲喂试粮 2 (添加 0 .2 %蛋氨酸 ) ,5、6饲喂试粮 3(添加 0 .8%蛋氨酸 )。 14日龄时 ,1、3、5组的鸡 ,每只分别接种 3× 10 4 个孢子化柔嫩艾美耳球虫卵囊 ,2 2日龄试验结束。结果表明 ,日粮中添加蛋氨酸与未添加蛋氨酸比 ,可以显著提高日增重(P <0 .0 5 )。日粮中添加 0 .8%的蛋氨酸与 0 .2 %相比 ,对试验期间肉仔鸡的生产性能的影响差异不显著 (P >0 .0 5 )。日粮中蛋氨酸水平和柔嫩艾美耳球虫感染对肉仔鸡的免疫器官指数影响不显著 (P >0 .0 5 ) ,但感染组的脾脏指数却都比未感染组大。日粮中蛋氨酸水平可以显著影响感染球虫肉仔鸡抗体的产量 (P <0 .0 5 )。随着日粮蛋氨酸水平的增加 ,血清抗体也随着增加。日粮中蛋氨酸水平可以显著影响感染球虫的肉仔鸡病变记分 (P <0 .0 5 )。日粮中添加 0 .8%的蛋氨酸 ,病变记分显著优于 0 .2 %组、0组 (P <0 .0 5 )。在球     

不同蛋氨酸和赖氨酸添加水平对五龙鹅生产性能的影响

试验选用 4 2日龄健康五龙鹅 ,研究了饲粮中不同蛋氨酸和赖氨酸水平对五龙鹅育成期生产性能的影响。试验采用 3× 3二因子设计 ,饲粮中蛋氨酸和赖氨酸添加水平均为 0 .1%、0 .2 %和 0 .3%三个水平。结果表明 :当饲粮中蛋氨酸含量为 0 .33% ,赖氨酸含量为 0 .70 %时 ,鹅的生产性能和饲料利用率最好。     

Effect of different levels of mannan‐oligosaccharide supplementation on the apparent ileal digestibility of nutrients,N‐balance and growth performance of weaned piglets

Several studies report that dietary mannan‐oligosaccharides (MOSs) improve the growth performance of piglets, however, only a few studies focus on nutrient digestibility. The aim of the study was to investigate the effect of dietary MOS on ileal digestibility of nutrients and on N‐balance and growth performance of piglets weaned at 28 days of age. Three experiments were conducted: a digestibility trial with a total of 30, simple T‐cannulated piglets (Exp. 1), a N‐balance trial with a total of 48 intact piglets (Exp. 2) and a performance trial with a total of 324 piglets (Exp. 3). In Exp. 1 and 2, the same five dietary treatments were carried out by supplementing the basal diet with 0, 1, 2, 4 g MOS or with 0.2 g antibiotic growth promoter (AGP, Avilamycin) per kg of diet. In Exp. 3, three dietary treatments were used as follows: the basal diet was supplemented no additive, 2 g MOS or 0.2 g AGP (Avilamycin) per kg of diet. Dietary MOS (2 or 4 g/kg) enhanced the ileal digestibility of crude protein similar to antibiotics. Addition of 1 g/kg MOS significantly increased the digestibility of Ca and P by 8.4% and 7.7% units, respectively; however, further increment did not enhance the absorption. Addition of 1 or 2 g/kg MOS significantly increased the ileal digestibility of lysine, methionine, cystine and threonine with the same magnitude or even more than the AGP. In our study, MOS supplementation had no influence on N‐balance and growth parameters. Because of the better apparent ileal digestibility of certain nutrients, however, the protein, lysine, methionine, cystine, threonine, Ca and P contents of the diet can probably be reduced without weakening the rearing performance of piglets, when the diet is supplemented with 2 g/kg MOS.     

Nanosize of zinc oxide and the effects on zinc digestibility,growth performances,immune response and serum parameters of weanling piglets

The aim of this study was to investigate the effect of dietary supplementation of nanosize zinc on zinc digestibility, growth performances, immune response and serum parameters of weanling piglets. Ninety‐six LYD weanling piglets were assigned to control, zinc oxide (ZnO), organic‐Zn (Zn‐methionine) and nanosize ZnO (nano‐Zn) groups with four replicates. The zinc was at the 120 mg/kg level in the treatment group's diet, while the control group's was 80 mg/kg Zn. The experiment results indicated that the nano‐Zn and organic‐Zn groups had significantly higher Zn digestibility compared to the ZnO and control groups. For the immune response traits, the IgG level and goat red blood cells (GRBC) antibody titer were nano‐Zn and organic‐Zn>ZnO>control; in the phytohemagglutinin (PHA) challenge test result, nano‐Zn>organic‐Zn>ZnO>control; in regard to the γ‐globulin level, nano‐Zn and organic‐Zn>ZnO and control, with significant difference between groups. In the serum parameters aspect, serum Zn concentration in nano‐Zn and organic‐Zn groups were higher than in the ZnO and control groups, serum growth hormone concentration was increased in the nano‐Zn group than in the other groups. In conclusion, nanosize zinc oxide for dietary supplementation can increase zinc digestibility, serum growth hormone levels and carbonic anhydrase activity and enhance the immune response of weanling piglets.     

Effects of different fermented soy protein and apparent ileal digestible lysine levels on weaning pigs fed fermented soy protein‐amended diets

Two experiments were conducted to evaluate the effect of different fermented soybean proteins and the apparent ileal digestible lysine levels on weaning pigs fed fermented soy protein (FSP)‐amended diets. In Exp. 1, 70 crossed piglets (6.25 ± 0.40 kg) were used in a 5‐week trial to evaluate two different FSP. In Exp. 2, 20 weaning barrows (6.15 ± 0.45 kg) were used in a metabolism trial to determine the effects of the apparent ileal digestible (1.2, 1.3, 1.4 and 1.5%) lysine levels in weaning pigs fed FSP (5%) diet. In Exp. 1, pigs fed the diet containing Lactobacillus spp. FSP showed higher nitrogen (N) digestibility (P < 0.05), lower blood urea nitrogen and serum creatinine levels (P < 0.05) than those fed the Aspergillus oryzae FSP diet. In Exp. 2, increasing dietary lysine levels increased the average daily gain, apparent dry matter, N digestibility, N retention and essential amino acids in the current study (P < 0.05), with the 1.5% showing the highest value. In conclusion, pigs fed Lactobacillus spp. FSP had a higher N digestibility than those fed A. oryzae FSP. The optimal apparent ileal digestibility lysine level in fermented soy protein diets (3550 kcal/kg metabolizable energy) for maximizing growth performance and N utilization in the first 7 days (6.25 kg) was 1.5%.     

Influence of dietary protein level and the amino acids methionine and lysine on leather properties of blue fox (Alopex lagopus) pelts.

The influence of dietary protein, methionine, and lysine on leather quality in blue fox pelts was studied. The pelt material originated from animals in two consecutive feeding trials (Exp. 1 and Exp. 2) with three protein levels: conventional, slightly lowered, and very low. The two lowest protein diets were fed as such or as supplemented with methionine or with lysine (lysine only in Exp. 2). The following physical leather properties were measured: breaking load (BRL), tensile strength (TEN), relative elongation at break (PEB), straining of skins at pelting, and shrinkage at dressing. A decline in the dietary protein content reduced BRL and, hence, leather firmness, and increased straining and the corresponding shrinking in Exp. 1. The supplemented methionine tended to improve leather strength and elasticity by increasing TEN and PEB in Exp. 1, whereas lysine elicited no response. Methionine supplementation at the slightly lowered protein level increased BRL in both experiments by almost 10% as compared with the respective non-supplemented diet. We conclude that with high protein quality diets, a level of 200 g/kg DM (as digestible protein) appears to be adequate for producing pelts with firm, elastic leather, provided that an adequate amount of methionine is included in the diet.     

维生素C对早期断奶仔猪免疫机能的影响

本试验研究维生素C对早期断奶仔猪生长性能的影响 ,以及满足最大免疫应答和最佳生长性能维生素C的需要量。试验采用 96头健康杜×长×大三元杂交、2 0± 2日龄断奶仔猪 ,按随机区组分为 3个处理 ,日粮VC添加水平为 0 ,75和 30 0mg/kg;每个处理设 8个重复 (栏 ) ,每个重复 4头猪 ,试验期为 2 1天。结果表明 ,添加维生素C可显著增加全血血红蛋白、红细胞压积和红细胞数 (P <0 .0 5 ) ;经植物凝集素 (PHA)诱导的皮褶厚度增加 ;但不影响淋巴细胞、单核细胞和噬中性细胞数 ;VC还有提高血清碱性磷酸酶 ,改善肠道铁吸收能力的趋势 ;维生素C对仔猪生产性能没有影响     

浓缩脱酚棉籽蛋白生长猪消化能评定及其对仔猪生长性能、血清生化指标和养分表观消化率的影响

本研究旨在通过猪消化代谢试验测定浓缩脱酚棉籽蛋白(CDCP)生长猪消化能,同时研究其对仔猪生长性能、血清生化指标和养分表观消化率的影响。试验选取65日龄、体重(38.80±2.60)kg的“杜×(长×大)”健康阉公猪8头,随机分成2组(每组4个重复,每个重复1头猪),分别饲喂基础饲粮和试验饲粮(80%基础饲粮+20%CDCP),单笼饲养,采用交叉法进行消化代谢试验测定消化能。然后选取(31±2)日龄、体重(10.00±0.60)kg的“杜×(长×大)”健康仔猪132头,按随机区组设计分成2组(对照组和CDCP组),每组6个重复,每个重复11头猪。对照组饲喂基础饲粮(鱼粉用量为4%),CDCP组饲喂试验饲粮(利用CDCP完全替代基础饲粮中的鱼粉),2种饲粮消化能和回肠标准可消化赖氨酸、蛋氨酸、苏氨酸、色氨酸水平均满足或超过NRC(2012)仔猪营养需要。试验期28 d。结果显示:生长猪对CDCP的能量表观消化率为86.64%,消化能为15.61 MJ/kg。2组仔猪的平均日增重、平均日采食量、料重比、腹泻率和血清生化指标差异均不显著(P>0.05);CDCP组的能量和粗脂肪表观消化率显著低于对照组(P<0.05),而2组干物质、粗蛋白质和粗灰分表观消化率差异不显著(P>0.05)。综上所述,CDCP生长猪消化能为15.61 MJ/kg。在消化能和回肠标准可消化赖氨酸、蛋氨酸、苏氨酸、色氨酸水平满足或超过NRC(2012)条件下,CDCP替代饲粮中鱼粉不影响仔猪的生长性能。     

Reduced dietary nitrogen with a high Lys:CP ratio restricted dietary N excretion without negatively affecting weaned piglets

We hypothesized that balancing the content of exogenous amino acids, especially lysine, to reduce protein content in swine diets could reduce nitrogen (N) pollution associated with animal husbandry. Two experiments (45 d each experiment) were performed on weaned piglets (Duroc × Landrace × Yorkshire, 28 d of age) to test this and to determine the optimal lysine to crude protein (Lys:CP) ratio in diet. In Exp. 1, 12 piglets (6 replicates [n = 6]) were fed diets containing different levels of CP (17% and 20%) but the same level of Lys. Increased CP content resulted in significant increases (P < 0.05) of average daily gain (ADG), average daily feed intake (ADFI), and body weight (BW), but did not affect the feed to gain ratio. In Exp. 2, 24 piglets (8 replicates [n = 8]) were fed 1 of 3 diets as follows: 1) 20% CP with a regular Lys:CP ratio (6.23%, control); 2) 17% CP with a reduced Lys:CP ratio (6.14%, LL); or 3) 17% CP with a standard Lys:CP ratio (7.32%, SL). The ADG, final BW, serum concentrations of growth hormone and insulin-like growth factor-1, villus height in the jejunum, and villus height to crypt depth ratio were the lowest in piglets fed LL diet, whereas blood urea N concentration was the lowest and the value of lipase activity was the highest in the piglets fed SL diet. The SL diet did not affect growth performance, intestinal morphology, or serum hormone concentrations, indicating that reduced dietary N with a high Lys:CP ratio can efficiently reduce dietary N excretion without negatively affecting weaned piglets.     

啤酒酵母葡聚糖对断奶仔猪生产性能及淋巴细胞转化率的影响

为了探讨啤酒酵母葡聚糖在断奶仔猪日粮中的适宜添加剂量及其对断奶仔猪细胞免疫功能的影响,本研究进行了2个试验。试验1选用100头(28±2)d断奶的二元杂交断奶仔猪,按单因子试验设计随机分为5个处理,分别饲喂含葡聚糖0、25、50、100mg/kg和200mg/kg的日粮。结果表明:随葡聚糖添加剂量的增加,平均日增重在14￣28 d及0￣28 d呈二次曲线变化(P<0.05)。试验2选用80头(28±2)d断奶的二元杂交断奶仔猪,随机分为2个处理,分别饲喂含葡聚糖0mg/kg和50mg/kg的日粮。在试验的第14天和第28天,每重复取1头仔猪前腔静脉采血,测定外周血淋巴细胞转化率。结果显示,在断奶仔猪日粮中添加50mg/kg葡聚糖提高了仔猪在14￣28d及0￣28d的日增重(P<0.05)。而且,也提高了仔猪在0￣14 d、0￣28 d及28￣35 d的平均日采食量(P<0.05)。但是对淋巴细胞转化率没有影响。结果表明:在断奶仔猪日粮中添加50mg/kg啤酒酵母葡聚糖,可以提高断奶仔猪的生产性能,而且没有性别差异。     

猪源发酵乳酸杆菌对保育猪生长性能、养分表观消化率、粪便微生物数量及血清免疫指标的影响

本试验研究了日粮中添加不同浓度的猪源发酵乳酸杆菌(Lactobacillus fermentum)对保育猪生长性能、养分表观消化率、粪便微生物数量和血清免疫指标的影响。选择160头保育猪,日龄为(30±2)d,体重为(7.85±0.68)kg,随机分成4组,每组4个重复,每个重复10头猪。对照组饲喂基础日粮,试验组在基础日粮中分别添加0.1%、0.2%和0.3%的猪源发酵乳酸杆菌制剂,试验期35d。结果显示,添加不同浓度猪源发酵乳酸杆菌对保育猪的各项指标均有改善效果,其中,0.2%发酵乳酸杆菌组的效果最好,与对照组相比,其平均日增重提高8.70%(P<0.05),料重比降低4.62%(P<0.05),日粮中粗蛋白质、钙和总磷的表观消化率显著提高(P<0.05),粪便中大肠杆菌数量显著下降(P<0.05),血清中IgG含量提高了8.39%(P<0.05)。因此,在保育猪饲料中添加猪源发酵乳酸杆菌能够提高机体免疫力和生长性能,提高日粮中粗蛋白质、钙和总磷的表观消化率,降低粪便中的大肠杆菌数量。     

The effect of dietary high energy density and carbohydrate energy ratio on digestive enzymes activity,nutrient digestibility,amino acid utilization and intestinal morphology of weaned piglets

This study evaluated the effect of high or low digestible energy ratio of carbohydrate in a high or normal dietary energy density on performance, amino acid utilization and intestinal functions of weaned piglets. A total of 32 healthy weaners (9.60 ± 0.13 kg) were allocated to two dietary energy densities (3,400 and 3,800 kcal/kg) and two digestible energy ratio of carbohydrate to fat (9:1 and 3:1) in a 2 × 2 factorial arrangement. There were eight piglets per treatment. The feed intake of piglets was significantly increased by dietary high carbohydrate ratio (9:1) (p < 0.01); however, this did not result in improved body weight gain (p > 0.05). The piglets fed high carbohydrate energy ratio had a reduced villus height/crypt depth (VH/CD) ratio in the duodenum (p < 0.05), and dietary high energy density further decreased the VH/CD ratio in the ileum (p < 0.01). In the duodenum, the lymphocyte count was increased by dietary high energy density (p < 0.05), while dietary energy density and carbohydrate energy ratio interacted to increase lymphocyte count in the ileum (p < 0.05). The serum cholesterol, triglyceride and low‐density lipoprotein were not significantly affected (p > 0.05), but dietary energy density interacted with dietary energy ratio to increase high‐density lipoprotein concentration (p < 0.05) in piglets fed reduced carbohydrate energy ratio. Dietary high energy density reduced energy digestibility (p < 0.05), whereas high carbohydrate energy ratio increased crude protein digestibility in the piglets (p < 0.05). The intestinal sucrase, lactase activities and serum concentrations of histidine, leucine, lysine, methionine, phenylalanine, alanine, glycine, tyrosine and citrulline were higher in the piglets fed dietary increased carbohydrate energy ratio. Oxidative stress markers and volatile fatty acids concentrations were altered by the dietary treatments. It was concluded that dietary high energy density could be detrimental to piglets intestinal functions and that increased carbohydrate energy ratio could affect amino acid utilization and body weight gain in weaner pigs.