日粮精粗比对舍饲安格斯犏牛生长性能和血清生化指标的影响

为探究不同精粗比日粮对短期舍饲育肥的安格斯犏牛生长性能和血清生化指标的影响，本研究选取30头年龄(4月龄)和体重((114.97±28.33) kg)相近的安格斯×大通牦牛的健康安格斯犏牛，随机分为3个处理组，每个处理组10个重复，每个重复1头牛。各试验组日粮精粗比分别为30∶70(C30组)、45∶55(C45组)和60∶40(C60组),预饲期10 d,正饲期90 d。结果表明：1)与C30组安犏牛相比，试验全期C45和C60组平均日增重(ADG)和胸围均显著提高(P<0.05),而料重比(F/G)显著降低(P<0.05);试验1～30 d的C45和C60组干物质采食量(DMI)显著降低(P<0.05),而61～90 d显著提高(P<0.05);试验1～30 d的C45和C60组及61～90 d的C60组ADG显著提高(P<0.05);试验1～30 d和61～90 d的C45和C60组F/G显著降低(P<0.05)。2)与C30组相比，C45组和C60组安犏牛的血清葡萄糖、总蛋白、白蛋白、球蛋白和游离脂肪酸等均显著提高(P<0.05)。综上...     

培养基及培养条件对除虫菊细胞生长的影响

以MS、ER、MG-5、B5、H、1/2MS、M9、NT及White为基本培养基,分析不同类型培养基对除虫菊细胞生长的影响,并以MS为基本培养基进行接种量、培养时间、pH、碳源、蔗糖质量浓度、不同蔗糖和葡萄糖组合以及光照条件试验,探讨除虫菊细胞生长的最佳培养条件。结果表明:适合除虫菊悬浮细胞培养的培养基为MS培养基,细胞接种量为8~12g/L、培养时间为20~25d,pH为5.8,采用自然散射光,单独使用蔗糖作为碳源时,质量浓度为30~40g/L有利于除虫菊细胞的生长。以蔗糖作为碳源时,添加25%的葡萄糖,除虫菊细胞的增长量可以提高12%。     

Effects of dietary concentrate level and chromium-methionine supplementation on ruminal fermentation,and ruminal bacterial and fatty acid composition in Tan lambs北大核心CSCD

This study evaluated the effects of dietary concentrate level and chromium methionine(Cr-Met)supplementation on ruminal fermentation and fatty acid composition, and ruminal bacteria abundance in Tan lambs. Forty male Tan lambs [(21.00±1.23) kg body weight, 5 months of age] were randomly assigned to four treatment groups with 10 lambs in each treatment. The treatments were: a low-concentrate (LC) diet (concentrate:forage, 35:65) without Cr-Met supplementation; a high-concentrate (HC) diet (concentrate:forage, 55:45) without Cr-Met supplementation; groups fed the HC diet with 0.75 or 1.50 g·d-1·lamb-1 Cr-Met (HCM and HCH, respectively). Ruminal fluid was collected on day 65 with an oral stomach tube about 3 h after the morning feed and samples used for fermentation analysis, fatty acid composition determination and bacterial DNA extraction. It was found that: 1) Ruminal pH, acetate proportion and acetate:propionate were greater (P<0.05) with the LC diet whereas microbial crude protein, propionate and valerate proportions were greater (P<0.05) with the HC diet. The acetate:propionate was greater (P<0.05) in the HCM group than in the HC group. 2) For the HC diet, the DNA abundances of Butyrivibrio fibrisolvens vaccenic acid subgroup (Butyrivibrio VA) and Ruminococcus flavefaciens were decreased (P<0.05), compared with the LC diet, whereas the DNA abundance of Anaerovibrio lipolytica was increased (P<0.05). For lambs fed the HC diet, DNA abundances of B. fibrisolvens stearic acid subgroup, Butyrivibrio VA, Butyrivibrio proteoclasticus, and A. lipolytica showed a linear decrease (P<0.05) with increasing Cr-Met supplementation level; However, the DNA abundance of R. flavefaciens showed a linear increase (P<0.05). 3) Compared with the LC group, the concentrations of t11 C18:1, trans C18:1, c9t11 CLA, t10c12 CLA, C18:2n6, and C18:3n3 were decreased by the HC diet without Cr-Met supplementation whereas the concentration of C18:0 was increased. There was a linear increase in t11 C18:1 and trans C18:1 with increasing Cr-Met supplementation level in lambs fed the HC diet. The results suggest that the HC diet inhibited the growth of ruminal bacteria involved in the ruminal biohydrogenation process, and the addition of Cr-Met had a potentially positive effect on conjugated linoleic acid (CLA) synthesis in body tissue. © 2022, Editorial Office of Acta Prataculturae Sinica. All rights reserved.     

论我国绿色饲料产业建设基本战略问题

我国饲料社会需求增长不可逆转，国内未来精饲料，秸秆饲料生产能力不足，国际饲料市场容量有限，决定了我国必须开辟新型饲料生产途径。绿色饲生产基础良好，生产技术和积累丰富等因素为我国绿色饲料产业大规模建设了充分必要条件。建设绿色饲料产业是未来我国农业建设的关键性内容。