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861.
The objective of the study was to investigate the effects of supplemental complex water soluble vitamins on production performance, blood biochemical parameters and oxidative resistance of dairy cows in spring and summer.The experiment was designed by 2×2 factorial randomized blocks design.Eighty healthy dairy cows with similar parity and body weight were randomly divided to four groups, with 7 days of adaptation and 70 d experimental phase.The dairy cows in group Ⅲ and Ⅳ were fed a basal diet supplemented with complex water soluble vitamins in spring.The dairy cows in group Ⅱ and Ⅳ were fed a basal diet supplemented with complex water soluble vitamins in summer.The results showed that the ADFI and daily milk yield of dairy cows receiving water soluble vitamin in spring were extremely significantly higher (P<0.01);The ADFI of dairy cows receiving water soluble vitamin was significantly higher in summer (P<0.05) and daily milk yield were extremely significantly higher (P<0.01);The butterfat rate was extremely significantly increased and SCC was extremely significantly decreased in spring and summer (P<0.01);Supplementation of water soluble vitamin was also significantly increased LYM (P<0.05).In summer, T-AOC, T-SOD were extremely significantly increased (P<0.01), and TP, CK, LDH, TP, HDL and ALB were extremely significantly decreased (P<0.01) by water soluble vitamin supplementation than that of control group.In conclusion, complex water soluble vitamins could increase the production performance and non-specific immune function, improve the oxidative resistance and relieved the heat stress of the dairy cows. 相似文献
862.
LI Hong-shuang QIU Dian-rui GUO Jian-jun GAO Yu-hong CUI Ya-li BAI Li-na 《中国畜牧兽医》2016,43(4):1105-1110
The present objective of the study was to investigate the effect of fans cooling on dairy cow in northern mountainous region of Hebei in summer.Two cowsheds with the same structure and feeding technics were used to investigate the effect of fans on indoor temperature and humidity, physiological parameters and milking performance of dairy cow.The results showed that the average ambient temperature in cowshed with fans was 1.5℃ lower than that of the control cowshed, and the average wind velocity was 0.49 m/s higher than that of the control cowshed, reaching to 0.66 m/s.Temperature-humidity index (THI) of cowshed with fans was significantly lower than that of the control shed during the period of fans running (P<0.05).Besides, the rectal temperature and respiration rate of dairy cows in cowshed with fans were significantly lower than of the control cowshed (P<0.05), and the milk yield per cow per day was 17.0% higher than that of the control cowshed (P<0.05), however, the milk fat, milk protein and milk sugar were no significant difference from the control (P>0.05).Overall, fans could decrease indoor environment, moderate heat stress and increase performance and health of dairy cows in northern mountainous region of Hebei. 相似文献
863.
YAO Wei YU Xue-wu CAO Dong ZHAO Xiao-tong GU Gui-bo CHEN Yao ZHANG Lei LIU Yao-chuan FENG Jun-ke 《中国畜牧兽医》2016,43(11):3080-3084
In order to understand the main bacterial pathogen species causing dairy cow mastitis in Liaoning, as well as the characteristics of drug sensitivity of the pathogenic E.coli,the milk samples from 75 dairy cows with clinical manifestations for mastitis in certain large-scale dairy farm in Liaoning were collected.The bacteria in milk were cultured and isolated with biochemical methods and in vitro drug sensitivity tests were processed with the isolated E.coli strains.The results showed that the main bacterial pathogen for dairy cow mastitis were E.coli(separation rate 58.7%),S.aureus(64.0%)and S.agalactiae(54.7%),and multiple infection including double and triple infection were identified.The drug sensitivity tests on the isolated E.coli indicated that the E.coli isolates were highly resistant to sulfonamides(resistance rate>85%)and chloramphenicol(resistance rate>30%),and they were relatively low resistant to ampicillin(9.5%),ciprofloxacin(9.5%),ceftiofur(7.1%)and ofloxacin(4.8%).The results was able to provide reliable theoretical basis for prevention and control of dairy cow mastitis in Liaoning area. 相似文献
864.
奶牛子宫脱出主要是在分娩后容易发生,是指部分或者整个子宫出现内翻,经过子宫颈和阴道脱出到阴门外。一般奶牛在分娩后的几个小时内就会发生该病,且呈急性经过,如果没有及时采取救治措施,往往会导致死亡,必须引起养殖户的足够重视,加强防治。 相似文献
865.
奶牛性控繁育技术,近年来在我县普遍推广,由于配种成本大,受胎率相对低,推广难度大.但是,对于奶牛养殖者来说,牛奶是他们实现利润的主要产品,母牛是他们实现生产效益的主体.由于母牛犊的经济效益显著高于公牛犊(不包括种公牛),多产母犊,少产公犊或者不产公犊就成了奶牛饲养者的一个共同愿望,多生一头母犊,就多一份经济收益.另外,连续生母犊,对加快牛群繁殖速度、缩短世代间隔、加快改良步伐也有重要的现实意义.奶牛业的发展助推了奶牛性控繁育技术的快速发展,从而诞生了奶牛性控冻精. 相似文献
866.
饲料是动物饲养的物质基础,合理的饲料配方不仅促进动物的健康生长、繁育,而且可提高畜禽养殖的经济效益。某校训练中心奶牛体重约为500 kg,平均产奶量为20 kg/d,乳脂率为3.51%,精料补充料营养量不能满足其维持和生产需要,特别是粗蛋白和能量方面差距明显,本文根据实际需要对奶牛精料配方设计进行了初步探讨。 相似文献
867.
869.
奶牛乳房炎一直以来是奶牛场常见病、高发病,也是造成奶牛养殖业损失最严重的疾病。病因复杂,如果不及时治疗就会导致群发,致使产乳量降低,造成较大经济损失。文章从奶牛乳房炎的类型、病因、防治措施等方面对奶牛乳房炎进行了介绍,以期为对奶牛养殖者提供参考。 相似文献
870.
奶牛乳房炎是奶牛乳腺因外伤、化学刺激、感染或发炎的一种病理反应,是奶牛的一种多发性疾病,也是奶牛产奶生产中危害最大的疾病之一。乳房炎不仅会造成奶产量、奶品质的下降、治疗费用增加和废弃奶损失,甚至还会导致奶牛快速淘汰,给牛场造成极大的经济损失。文章提出奶牛乳房炎的防控措施应采取预防为主,以防治结合,加强饲养监管和保持舍卫生。 相似文献