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1.
酮粉法检测泌乳牛尿酮乳酮的应用研究   总被引:15,自引:1,他引:14  
荷斯坦泌乳牛尿、乳酮体的酮粉法定性试验表明:尿酮阳性率为29.25%,乳酮阳性率为10%。尿、乳阳性牛的血酮、血糖、乳酮、尿酮定量测定表明:酮粉法判定泌乳奶牛亚临床酮病,尿酮阳性反应具有早期、敏感、准确性低的特点。乳酮阳性反应具有准确、敏感性低、方便等特点。二者同时定性检测具有互补作用。  相似文献   
2.
Foal first diarrhoea is one of the most prominent problems in the early life of horses. Probiotics might have the potency to prevent or at least diminish neonatal diarrhoea. We hypothesised that the treatment of foals with probiotic strains of Lactobacillus rhamnosus and Enterococcus faecium starting early after birth and then daily over 2 weeks would prevent or mitigate foal heat diarrhoea. The influence of this probiotic treatment on diarrhoea incidence and growth and health performance of young foals was investigated. Thirty‐four foals were randomly allocated to two groups. From day 1 to 14 of life, the foals received either placebo (PG, n = 16) or the probiotic treatment (TG, n = 18). Clinical examination was performed, and the faeces consistency score (FCS, 1–5; with diarrhoea defined by ≤3) was recorded once per day in weeks 1 and 2 and once weekly in weeks 3–8 of life (WL). The body height was measured at birth and after two and eight WL. Diarrhoea occurred in the 1st WL in 19% and 61% of PG and TG foals respectively. In the 1st WL, diarrhoea lasted 0.3 ± 0.8 and 1.6 ± 1.4 days in PG and TG foals respectively. In the 2nd WL, diarrhoea occurred in 94% and 84% of PG and TG foals, respectively, and lasted for 3.0 ± 1.5 and 3.7 ± 1.6 days respectively. At least two periods of diarrhoea developed in 33% and 65% of PG and TG foals respectively. The TG foals grew slightly slower than the PG foals. The results indicated that the probiotic treatment of neonatal foals as performed in this study was not suitable to reduce diarrhoea within the first two WL, because contrary to the hypothesis, the TG foals suffered more frequently and for longer periods from diarrhoea than the PG foals.  相似文献   
3.
犊牛是牧场发展的后备军,优质的犊牛培育是牧场可持续发展的有利保障之一。因此,科学的犊牛饲养管理措施和合理的犊牛饲养模式对于犊牛培育极其重要。通过对自动化饲喂饲养模式下哺乳犊牛的饲喂技术、管理措施以及疾病预防等方面进行综述,重点介绍初乳、饲喂计划、补饲、奶粉及开食料、饲喂标准、饲养环境、管理细节差异、疾病治疗方案等内容,以期对自动化饲喂饲养模式下的牧场提供参考。  相似文献   
4.
This study sought to determine whether an increase in resistance of Rhodococcus equi to the antibiotics rifampin and erythromycin occurred over a 10-year period. This was carried out by the use of E test strips for rifampin and erythromycin to determine the MIC (minimum inhibitory concentration) values of Rhodococcus equi to this combination of antibiotics.The findings of this study indicated that there was an increase in resistance of Rhodococcus equi to rifampin and erythromycin over the 10-year period. The MIC for rifampin increased from 0.081 μg/ml in 1996 to 0.187 μg/ml in 2006 and from 0.258 μg/ml for erythromycin during the years prior to 2000 to 0.583 μg/ml in 2006.This finding suggests that there may be a problem in the treatment of Rhodococcus equi infections in foals in the future, particularly as the number of drugs available for treatment of Rhodococcus equi infection is limited because of the intracellular capabilities of this bacterium. Antibiotics used in its treatment have to be able to penetrate the polysaccharide cell wall of Rhodococcus equi as well as the alveolar macrophages in which the bacterium is capable of surviving.  相似文献   
5.
Intramammary infusion of Bifidobacterium breve (B. breve)-induced somatic cell (SC) counts, chemiluminescent response (CL), lactoferrin (LF) concentrations and mastitis-causing pathogens from quarters with subclinical mastitis were measured to evaluate innate immune response of mammary glands in dairy cows at 3 to 4 weeks before drying off. SC counts in 7 quarters of 7 control cows and 5 quarters of 6 cows with mastitis increased markedly on day 1 and SC values in control cows were significantly (P<0.05) increased and returned to pre-infusion levels on day 5 after B. breve-infusion. CL values in both groups increased markedly on day 1 and then decreased after B. breve-infusion; however, CL values in cows with mastitis did not return to normal levels on day 5 and at postpartum. The CL values were highly correlated with their SC counts in milk from both groups. LF concentrations increased toward day 3 after B. breve-infusion and were higher in cows with mastitis. B. breve-infusion eliminated 16.6% (1/6) of pathogens from 6 quarters with chronic subclinical mastitis. B. breve-induced SC responses in quarters from 3 cows with mastitis showed characteristic patterns of recovery, persistent and new infections. B. breve-induced SC counts in quarters from the cows in the pre-drying off were lower (25.7–70.6%) than those of the cows in mid-lactation. The intrinsic innate immune response in cows on pre-drying off may be decreased and appears to be insufficient to eliminate pathogens from mammary gland in the pre-drying off.  相似文献   
6.
基于隐马尔科夫模型的深度视频哺乳母猪高危动作识别   总被引:1,自引:4,他引:1  
哺乳母猪的高危动作和仔猪存活率有密切关系,能直接体现其母性行为能力,而这些高危动作又与其姿态转换的频率、持续时间等密切相关。针对猪舍环境下,环境光线变化、母猪与仔猪黏连、猪体形变等给哺乳母猪姿态转换识别带来的困难。该文以梅花母猪为研究对象,以Kinect2.0采集的深度视频图像为数据源,提出基于Faster R-CNN和隐马尔科夫模型的哺乳母猪姿态转换识别算法,通过FasterR-CNN产生候选区域,并采用维特比算法构建定位管道;利用Otsu分割和形态学处理提取疑似转换片段中母猪躯干部、尾部和身体上下两侧的高度序列,由隐马尔科夫模型识别姿态转换。结果表明,对姿态转换片段识别的精度为93.67%、召回率为87.84%。研究结果可为全天候母猪行为自动识别提供技术参考。  相似文献   
7.
试验评估不同水平柑橘渣对奶牛泌乳性能、养分消化及乳成分的影响.将32头泌乳性能一致的奶牛随机分为4个组,每组4个重复,每个重复2头.对照组饲喂粗脂肪水平为3%的日粮,处理组分别饲喂粗脂肪水平为5.5%的日粮同时添加0 (T1)、5%(T2)和10% (T3)柑橘渣.结果 显示,与对照组相比,处理组奶牛的粗脂肪摄入量、干...  相似文献   
8.
对王不留行的命名、植物形态、区域分布、药材鉴定、生物学特性、化学成分及其主要功能、临床应用进行了详细的论述,以期为王不留行的进一步研究提供理论依据,并有利于王不留行的深入探讨和研究,从而为壮大祖国中药医学事业的发展奠定基础。  相似文献   
9.
铬对泌乳期奶牛的生产性能和主要生理指标的影响   总被引:6,自引:0,他引:6  
研究了泌乳期奶牛日粮中添加吡啶羧酸铬或赖氨酸铬对其生产性能和血液主要生理指标的影响。选择75头泌乳前期(〈80d)的荷斯坦奶牛随机分为试验组A、B和对照组C。试验组A和B每天日粮中分别补充吡啶羧酸铬和赖氨酸铬,供试期间对照组C不添加有机铬。结果表明:铬可提高泌乳期奶牛的生产性能,增强和改善泌乳奶牛的免疫力和应激状态。试验组A和试验组B泌乳量高于对照组C(P〈0.01);试验组B血清中的甘油三酯的浓度低于对照组C(P〈0.05);试验组A血清中胰岛素浓度低于对照组C(P〈0.01);试验组A和试验组B血清中葡萄糖浓度都高于对照组C(P〈0.01);试验组A和试验组B血清中皮质醇的浓度分别比对照组C低7.21nmol/L和4.92nmol/L,试验组A和试验组B血清中IgG的浓度分别比对照组C高2.1g/L和3.1g/L。  相似文献   
10.
以3头安装有永久性瘤胃瘘管的泌乳前期荷斯坦奶牛为试验动物,在精粗比为55:45的日粮条件下,采用Insacco法测定了奶牛常用饲料瘤胃内干物质和淀粉的降解规律。试验结果表明。不同饲料干物质和淀粉的降解率不同。能量饲料中,麸皮干物质和淀粉的瘤胃降解率高于玉米:蛋白质饲料中,干物质和淀粉的降解率由高到低顺序依次是豆粕〉胡麻饼〉棉粕:常用粗料中,玉米青贮干物质和淀粉的降解率均高于青干草。  相似文献   
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