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161.
The reproductive physiology of the impala was studied in the Kruger National Park. The data concerning the hypophysial hormones, the androgenic hormones and ovarian histology are discussed in relation to the behaviour of the animal.

It was found that the male animal shows the most profound behavioural changes which occur during the mating season. These changes are induced by an increase of interstitial cell-stimulating hormone which leads to an increase in androgenic hormone. The female shows relatively few behavioural changes during the mating season, the only change being at the time of oestrus.

On the basis of the data presented and information reported for domestic animals, it is postulated that the behaviour of the male impala plays an important role in determining the breeding season.  相似文献   
162.
为了提高葡萄园资源利用率和综合效益,构建了牧草-鹅-鲜食葡萄循环生态种养体系。实践表明,在设施葡萄园推广套种牧草养鹅、鹅粪生产有机肥料、有机肥料种植葡萄和牧草等高效配套技术,取得了良好的经济效益、生态效益和社会效益。实施牧草-鹅-鲜食葡萄循环生态种养是江苏沿海地区发展现代农业的一种有效生产模式。  相似文献   
163.
从宁夏部分奶牛场(牧场、养殖小区)采集94份临床型乳房炎乳样、70份隐性乳房炎乳样,并分离鉴定出4株非脱羧勒克菌,其中临床型乳房炎分离出1株、隐性乳房炎分离出3株。药敏试验结果表明,4株非脱羧勒克菌均对链霉素、氨基糖苷类、喹诺酮类、头孢类药物敏感;对磺胺类、林可胺类药物则产生不同程度的耐药性。  相似文献   
164.
苏加义  赵红梅 《草业科学》2006,23(11):83-87
目前我国进入“WTO后过渡期”,加快向市场经济和自由贸易制度靠拢。这就要求我国草原畜牧业要改变传统经营方式,从宏观层面合理配置畜牧业资源。通过实施“北繁南育”战略,将北方地区草食家畜的繁殖优势与南方区域的草食家畜育肥优势有机结合起来,生产符合国内外市场需要的绿色畜产品,同时有效解决我国生态环境恶化、畜产品竞争力低下、农牧民增收困难的矛盾,实现我国传统草原畜牧业向现代化草原畜牧业的转变。  相似文献   
165.
从化石和历史文献角度概述了我国古今存在的兔种,分析了我国家兔起源驯化过程,并通过历代对兔的记载纵观我国养兔发展,为我国家兔起源及驯化历史提供一定参考依据。  相似文献   
166.
Background: Endocarditis is a rare heart condition with variable clinical expressions in equids. Risk factors for this disease are incompletely understood. Objective: Describe risk factors for endocarditis in equids. Animals: One hundred and fifty‐three equids admitted to Liège University, 9 diagnosed with endocarditis and 144 free from endocarditis but admitted to the hospital with a differential diagnosis including this disease. Methods: Retrospective case‐control study. Results: Equids with endocarditis were significantly younger (mean age = 4.84 ± 5.74 years) than control equids (mean age = 10.8 ± 7.73 years) (P= .01). No sex or breed predisposition was observed. Animals with hyperthermia (odds ratio [OR] = 24.4; confidence interval [CI] = 1.40–428), synovial distension (OR = 13.4; CI = 3.00–59.8), lameness (OR = 6.52; CI = 1.63–26.1), hyperglobulinemia (OR = 26.4; CI = 3.03–229), hypoalbuminemia (OR = 11.4; CI = 1.34–96.8), hyperfibrinogenemia (OR = 9.81; CI = 1.16–82.7), or leukocytosis (OR = 7.12; CI = 1.40–36.4) presented a significantly higher risk of having endocarditis than control horses. The presence of two of the clinical signs mentioned above significantly increased the probability of a diagnosis of endocarditis (P≤ .05). Conclusions and Clinical Importance: Age is associated with equine endocarditis. The diagnostic value of certain clinical signs and abnormalities in blood parameters in this disease are described.  相似文献   
167.
Statistical control charts were used to detect process change in pig production. Two charts were tested to detect small deviations in production processes: the cumulative sum (CUSUM) control chart and the exponentially weighted moving average (EWMA) control chart. A Monte-Carlo simulation was used for developing an optimal design of the EWMA and the CUSUM charts. The traits piglets born in total and the return to oestrus rate were considered. Over a given time period, small shifts were purposely implemented to test the performance of the charts. The average time to signal (ATS) and false positive rate (FPR) were taken as classification parameters to evaluate the performance of the charts. All shifts in the number of piglets born in total were detected with CUSUM and EWMA control charts. The trait piglets born in total showed an ATS ranging from 1.3 (FPR = 33.5%) to 6.8 weeks (FPR = 1.2%) using the CUSUM chart. The EWMA chart presented an ATS which ranged between 2.0 (FPR = 14.9%) and 6.3 (FPR = 1.9%) weeks. The application of the CUSUM to the return to oestrus rate resulted in an ATS of 2.6 (FPR =  38.3%) to 15.6 weeks (FPR = 3.0%) and the EWMA chart produced a signal between 4.1 (FPR = 14.5%) and 16.4 weeks (FPR = 1.4%). Both charts appear to be useful tools for tracking commercial swine farm processes and detecting emerging change in process performance.  相似文献   
168.
The present study examined, at identical daily nutrient intakes, the impact of separating protein and lactose intakes across two daily meals on the metabolic and endocrine status in heavy veal calves. Calves were assigned to one of six degrees of separating protein and lactose over the two meals (termed nutrient synchrony, SYN 1-6; 6 calves/treatment). They were fed the protein-rich (P-)meal and the lactose-rich (L-)meal at 06:00 and 18:00h, respectively, or vice versa. At SYN 1, calves were fed with 50% of the daily protein and 50% of the daily lactose intake in each meal. Protein and lactose were iso-energetically exchanged between the two daily meals from SYN 1 to 6. At SYN 6, 85% of the daily protein and 20% of the daily lactose was fed in the P-meal and the remainder in the L-meal. Blood samples were collected hourly during 24h. Mean 24h glucose concentrations increased and insulin concentrations decreased from SYN 1 to 6. Postprandial 5h areas under concentration curves (AUC(0-5h)) of glucose increased with increasing meal lactose content. AUC(0-5h) of non-esterified fatty acids increased after P- and L-meals from SYN 1 to 6. Urea concentrations increased after L-meals from SYN 1 to 6, but decreased after P-meals from SYN 1 to 6. Insulin AUC(0-5h) decreased after L-meals and after P-meals from SYN 1 to 6. Nutrient asynchrony did not affect insulin-like growth factor-1, glucagon, growth hormone, leptin, 3,5,3'-triiodothyronine and thyroxine. In conclusion, separation of protein and lactose intake over meals inhibited insulin responses to a lactose-rich meal in heavy veal calves despite high plasma glucose concentrations.  相似文献   
169.
西藏“一江两河”流域中部草地沙漠化与防治   总被引:3,自引:0,他引:3  
据1:3.5×10^4假彩色红外航空像片室内判读与野外调查,本区沙漠化草地可分为中度及轻度两种,面积12.823万hm^2,导致草地沙漠化的人为因素主要是超载过牧,樵柴,放牧制度不合理等,草地沙漠化防治可采取生物,管理及工程等措施。  相似文献   
170.
猪支原体肺炎是生猪养殖中较为常见的一种猪肺疾病类型,该病具有高度接触性、慢性传染性等特点,如果未能得到及时有效的处理则会扩散至整个生猪群体范围,对生猪养殖的经济效益造成严重损害。且在猪支原体肺炎的发生中,该病经常与圆环病毒及其他病原体进行混合感染,进一步加深生猪病情,对生猪养殖造成非常严重的经济损失。养殖人员在生猪养殖中务必要加强对于猪支原体肺炎的重视程度,积极了解猪支原体肺炎的临床症状与发生特点,采取有效的防治措施以避免猪支原体肺炎发生。该文主要论述猪支原体肺炎的发生特点、临床症状以及诊断防治。  相似文献   
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