肉牛常见疾病的防治

牛是养殖业中的一项重要养殖对象,有着巨大的经济效益与社会效益。在养殖过程中我们要做好牛疾病的防治,以便能够及时发现、及时治疗,减少经济损失,提升经济效益。本文就牛犊腹泻、牛结核、牛感冒、牛消化不良等疾病的防治入手进行论述并提出了防治策略。     

平菇菌糠饲喂肉牛增重试验

平菇菌糠经过微贮处理后,替代肉牛日粮中部分粗料(玉米芯)饲喂西门塔尔与本地黄牛的杂交牛(简称西杂牛),试验期为60 d。结果表明,试验组平均个体总增重52.41 kg,平均日增重873.04 g;对照组平均日增重710.02 g,试验组比对照组日增重提高23.0%(P0.05),经济效益提高48.8%,效益明显。     

浅谈牛病的流行特点及防治措施

随着养牛业也取得了较大的突破,不过也出现不少问题,其中影响最为严重的就是牛病,不仅影响畜牧业的产业链条,更是不利于整个生物圈的健康发展.从我国养牛产业发展的现状来看,危害牛群的疫情渐趋复杂.本文主要针对牛病的流行现状作重点分析,并且提出一些有效的防治策略.     

牛、马肾炎的诊断和防治措施

肾炎通常是指肾小球、肾小管或肾间质组织发生炎症的统称.病的主要特征是肾区敏感和疼痛,尿量减少,尿液含有病理产物.牛可发生,以马、猪多发.本文从本病的发病原因、临床症状(急性、慢性和间质性)、病理变化、诊断要点、防治措施等方面进行了阐释.本病重在预防,减少感染机会.     

关于牛结核病防治措施的探究

近年来,我国的畜牧业发展迅猛,牛养殖规模不断扩大,但是很多疾病也开始出现,其中严重的一种就是牛结核病。牛结核病是一种人兽共患的慢性传染病,是国家二类动物疫病。其特点是在多种组织器官形成结核结节和干酪样坏死或者钙化结节病理变化。该病在世界各地均有发生,在公共卫生上具有重要意义。因此,笔者认为,只有采取有效的方法对结核病进行防治,才能达到逐步控制和消灭结核病的目的,从而提高生产性能,增加养殖效益。     

瘤胃异常代谢产物组胺影响反刍动物生产性能和瘤胃性能的研究现状

高精低粗的饲粮结构会引起奶牛瘤胃内乳酸和挥发性脂肪酸浓度升高,瘤胃液p H降低,导致瘤胃内微生物区系发生改变,引起瘤胃内异常代谢产物组胺增加。组胺可引起奶牛多种疾病,并使奶牛生产性能下降。本文综述了瘤胃异常代谢产物组胺的产生原因、相应作用机理,以及组胺对反刍动物的生产性能及瘤胃特性的影响。     

农药助剂牛脂胺聚氧乙烯醚的毒性及其分析技术研究进展

牛脂胺聚氧乙烯醚是一类广泛用于草甘膦制剂的农药助剂。大量研究表明,该助剂的毒性大于其活性成分草甘膦,因而引起了国内外研究人员的关注。本文对牛脂胺聚氧乙烯醚的结构、毒性以及其目前在环境中的分布水平和分析方法等内容进行了综述,旨在为牛脂胺聚氧乙烯醚在我国农药助剂领域的进一步研究、规范使用和管控提供科学依据。     

瘤胃中添加剂的甲烷减排作用及甲烷厌氧氧化北大核心CSCD

反刍动物每年排放甲烷(CH_(4))约1亿t,是全球变暖的重点关注对象。在瘤胃发酵过程中产生CH_(4)会造成2%~12%的能量损失。目前,有多种饲料添加剂能从不同角度降低CH_(4)排放量,但都存在一定缺陷;而甲烷厌氧氧化作为自然环境中重要的甲烷汇亦有可能在瘤胃中存在。本文综述了不同饲料添加剂对CH_(4)减排的作用以及甲烷厌氧氧化在瘤胃中存在的可能性,以期为反刍动物CH4减排提供新思路。     

Effects of Bacillus amylolyticus on Rumen Dry Matter Digestibility,Fermentation Parameters and Metabolites of Dairy Cows北大核心CSCD

This experiment was conducted to study the effects of Bacillus amylolyticus on rumen dry matter digestibility, fermentation parameters and metabolites of dairy cows. Experiment 1: six dairy cows with permanent fistula and had the similar parity (2 to 3 fetuses), body weight [(662 ±57) kg], lactation days [(160 ± 22) d] and milk yield [(36.1 ±3.8) kg / d], were randomly divided into 3 groups with 2 cows per group. Using 3 ×3 Latin square design, each group was extra fed 0 (control group), 5 ×109 and 5 ×1010 CFU / d Bacillus amylolyticus, the trial period was 3 periods, 13 days for each period, including 10 days for the pre-trial period and 3 days for the trial period. At the beginning of the trial period, the rumen dry matter digestibility of cows was measured by nylon bag method. Experiment 2: thirty dairy cows with similar parity [(2.5 ±0.3) fetuses], initial body weight [(559.2 ± 7. 4) kg], milk yield [(35. 2 ± 1. 5) kg / d] and lactation days [(99 ± 22) d] were randomly divided into three groups with 10 cows in each group. Cows in the 3 groups were extra fed with 0 (control group), 5 ×109 and 5 ×1010 CFU / d Bacillus amylolyticus, respectively. The pre-trial period was 10 days and the trial period was 42 days. The rumen fluid was collected on the last day of the trial period, and the rumen fermentation parameters and metabolites were determined. The results showed as follows: compared with the control group, 1) supplementary feeding of 5 × 1010 CFU / d Bacillus amylolyticus could significantly improve the rumen dry matter digestibility of dairy cows at 12, 24, 36, 48 and 72 h (P <0.05), supplementary feeding of 5 ×109 CFU / d Bacillus amylolyticus could significantly improve the rumen dry matter digestibility of dairy cows at 36 and 48 h (P <0.05); 2) supplementary feeding of 5 ×109 CFU / d Bacillus amylolyticus could significantly increase the contents of isobutyric acid, butyric acid, isovaleric acid, valeric acid, total volatile fatty acid and microbial protein in the rumen of dairy cows (P < 0. 05), supplementary feeding of 5 × 1010 CFU / d Bacillus amylolyticus could significantly increase the contents of isobutyric acid and isovaleric acid in the rumen of dairy cows and significantly reduce the rumen acetic acid / propionic acid (P < 0. 05), supplementary feeding of 5 ×109 and 5 ×1010 Bacillus amylolyticus had no effects on rumen pH and ammonia nitrogen content (P >0.05); 3) eleven metabolic pathways related to differential metabolites were detected, and ascorbic acid and alginate metabolism were significantly enriched (P < 0. 05) . In conclusion, Bacillus amylolyticus can increase the rumen dry matter digestibility, and improve the rumen fermentation function of dairy cows by affecting the content of rumen metabolites. By comprehensive analysis, supplementary feeding of 5 × 109 CFU / d Bacillus amylolyticus can achieve better effect. © 2023 Authors. All rights reserved.     

Effects of Compound Plant Nutrients on Rumen Fermentation Parameters,Rumen Microbiota and Fatty Acid Composition of Longissimus dorsi Muscle in Finishing Small Tail Han Sheep北大核心CSCD

This study was conducted to investigate the effects of compound p1ant nutrients (CPN) on rumen fermentation parameters, rumen microbiota and fatty acid composition of longissimus dorsi musc1e in finishing sma11 tai1 Han sheep. Sixteen 4-month-o1d finishing sma11 tai1 Han sheep with an initia1 body weight (BW) of (24.18±0.31) kg were random1y divided into two groups, name1y, with 8 rep1icates per group and 1 sheep per rep1icate. The sheep in the contro1 group were fed a basa1 diet, whereas the sheep of the contro1 group (CPN group) was fed the basa1 diet supp1ementation with 3‰ CPN. The experiment 1asted for 97 days after 7 days adaption. The resu1ts showed as fo11ows: compared with the contro1 group, 1) adding CPN decreased the concentration of ammonia nitrogen (NH3-N) (P<0.05); 2) CPN supp1ementation affected beta diversity of rumen microbiota; 3) the re1ative abundance of Acidobacteriota, Erysipe1otrichaceae_UCG-002, Lactobacillus, and Megasphaera were enhanced by adding CPN (P<0.05), whereas, the re1ative abundance of Bacteroidetes and Prevotella was 1ower (P<0.05); 4) the supp1ementation of CPN had no significant effect on fatty acid composition of longissimus dorsi musc1e of fattening sma11-tai1ed Han sheep (P>0.05); 5) the contents of tota1 MUFA, C18:1n9c, C14:1, C16:1, C18:2n6c, C18:3n3 and n-3PUFA in the longissimus dorsi musc1e were corre1ated with the re1ative abundance of Megasphaera, Erysipe1otrichaceae_UCG-002, Succiniclasticum and Ruminococcus (P<0.05). In conc1usion, CPN can regu1ate the rumen microbiota structure and reduce the rumen NH3-N concentration of fattening sma11-tai1ed Han sheep. In production practice, CPN can be used as a rumen eco1ogica1 regu1ator. © 2023 Authors. All rights reserved.