共查询到20条相似文献，搜索用时 62 毫秒
1.
概述
凡达到适配年龄或产后80天以上仍不发情或虽然发情但经过三个情期配种仍不受孕的母牛，均可视为不孕。下面就奶牛不孕症产生的原因、治疗方法、产生的后果等作简单陈述，仅供参考。 相似文献
2.
3.
4.
5.
在一定的变差范围内 ,季节、年龄、膘成等因素 ,对母黄牛繁殖过程中所出现的发情周期、持续期均有一定影响 ,其中在发情周期分布中 ,以清明至立冬期间、4～ 8岁阶段、七成膘者较为正常。在发情持续期中有 63 .61%的母黄牛在夏、秋两季发情 ,具有明显的季节性 ,其次是不同年龄、不同膘成的母黄牛之间也各有差异 相似文献
6.
黄牛进入初情期后,便开始出现发情表现.一次发情开始到下一次发情开始的间隔时间称为一个发情周期.黄牛的发情周期平均为21d,正常变动范围是18～24d,但还有不少黄牛的发情周期在正常范围之外,或长或短.为了摸清平原县本地黄牛发情周期长短变化情况及影响因素,以便及时观察、检查、输精,从而提高复配指数和受胎率,我们对平原县黄牛发情周期长短及影响因素进行了调查,现将调查结果报告如下:1 调查内容与方法1.1 调查内容按一个发情周期少于17d、18d～24d、25d以上,将所调查黄牛分为三类,统计每一类黄牛所占百分数并分析影响发情周期长短的因素. 相似文献
7.
猪人工授精已经成为现代化养猪业发展的重要技术之一,已被越来越多的人所接受。在生产实践中取得了明显的经济效益。笔者结合自己的工作经验,对1255头各类年龄的发情母猪,情期內的输精时间,受孕率及产仔数等作了对比观察。兹将情况介绍如下。 相似文献
8.
牛 配种适龄:初配母牛为18～30月、且黄牛较水牛略早。母牛最佳利用期为10～15年。最佳配种时间:母牛一年四季都可发情、不受季节影响,但以春季4～5月,秋季8～10月为配种旺季。母牛发情持续时间黄牛为10～20小时、水牛为48～72小时,因此,黄牛应在发情后8～12小时配种、水牛应在发情后第二天下午或第三天上午配种好。母牛的发情周期黄牛为18～21天、水牛为18～25天。妊娠期黄牛为285天、水牛为305～307天。 相似文献
9.
10.
养猪生产中常见到青年母猪达到发情年龄而不见发情；经产母猪在仔猪断奶后仍无发情表现或发情不明显，这些现象对生产的影响很大。 相似文献
11.
12.
13.
Evidence for the non-involvement of the uterus in the lifespan of the corpus luteum in the cyclic dog 总被引：1，自引：0，他引：1
Progesterone levels in peripheral blood of dogs were analysed during the cycle in which hysterectomy (n = 5) or sham surgery (n = 3) was performed as well as during the cycle of dogs (n = 5) hysterectomized at least one year prior to this study; the data were compared with the findings in control dogs (n = 3). The averages of the duration of the luteal period observed in the three experimental groups were not significantly different from those of control dogs. Immediately after surgery, the progesterone level decreased from 25 to 50% of the presurgical level, but returned to presurgical level in about four days. Prolactin levels were elevated for about 30 h after surgery. Nevertheless, the averages of the mean prolactin levels for each animal during the luteal period of the experimental groups were not significantly different from those of control dogs. It is concluded that in the dog, the uterus is not involved in the lifespan of the cyclic corpus luteum. 相似文献
15.
16.
嗅源是军犬嗅觉作业训练的依据.军犬鉴别中嗅源能力的培养在整个鉴别训练中占有重要地位,关系到鉴别训练的成败和鉴别能力的提高.所以,军犬在嗅认嗅源时必须按照训犬员的指令充分、细致地感受嗅源气味,并且对嗅源气味产生兴奋反应.如何培养军犬充分嗅认嗅源以及及时解决嗅认过程中出现的问题,成为我们进行鉴别训练的关键.…… 相似文献
17.
Meschan EM Peham C Schobesberger H Licka TF 《Veterinary journal (London, England : 1997)》2007,173(3):578-584
As there is no statistical evidence that saddle fit influences the load exerted on a horse's back, this study was performed to assess the hypothesis that the width of the tree significantly alters the pressure distribution on the back beneath the saddle. Nineteen sound horses were ridden at walk and trot on a treadmill with three saddles differing only in tree width. Kinetic data were recorded by a sensor mat. A minimum of 14 motion cycles were used in each trial. The saddles were classified into four groups depending on fit. For each horse, the saddle with the lowest overall force (LOF) was determined. Saddles were classified as "too-narrow" if they were one size (2 cm) narrower than the LOF saddle, and "too-wide" if they were one size (2 cm) wider than the LOF saddle. Saddles two sizes wider than LOF saddles were classified as "very-wide". In the group of narrow saddles, the pressure in the caudal third (walk 0.63 N/cm(2)+/-0.10; trot 1.08 N/cm(2)+/-0.26) was significantly higher compared to the LOF saddles (walk 0.50 N/cm(2)+/-0.09; trot 0.86 N/cm(2)+/-0.28). In the middle transversal third, the pressure of the wide saddles (walk 0.73 N/cm(2)+/-0.06; trot 1.52 N/cm(2)+/-0.19) and very-wide saddles (walk 0.77 N/cm(2)+/-0.06; trot 1.57 N/cm(2)+/-0.19) was significantly higher compared to LOF saddles (walk 0.65 N/cm(2)+/-0.10/ 0.63 N/cm(2)+/-0.11; trot 1.33 N/cm(2)+/-0.22/1.27 N/cm(2)+/-0.20). This study demonstrates that the load under poorly fitting saddles is distributed over a smaller area than under properly fitting saddles, leading to potentially harmful pressures peaks. 相似文献
18.
19.
Observations on the Pathology of the Spleen of the Cat 总被引：1，自引：0，他引：1
Abstract— Lesions were found in the spleen of four of sixty-three cats examined post mortem in the department, and comprised two examples of lymphosarcoma, one of chronic fibrinous peritonitis and one of subcapsular haematoma. Abnormalities were found in two cat spleens received from veterinary surgeons in general practice. In one cat the abnormalities were an haemangiosarcoma with secondary deposits in the liver and in the other extensive mast cell infiltration. In addition lesions were detected in the spleen of three of eighty-seven cats examined post mortem in general practice. The lesions were: multiple secondary deposits of adenocarcinoma from a primary tumour of the mammary gland, a ruptured spleen and a foreign body below the splenic capsule. Résumé— L'examen microscopique de soixante-trois chats pratiqué dans le service a permis de rencontrer quatre fois des lésions de la rate, dont deux lymphosarcomes, une péritonite capsulaire fibrineuse et un hématome sous-capsulaire. D'autre part des lésions ont été trouvées dans deux rates de chat expédiées par des vétérinaires exerçant en pratiaue générale. Chez un chat il s'agissait d'un htmangiosarcome avec métastases hépatiques et chex l'autre d'une infilt ation diffuse par des mastocyta. De plus, on a rencontré des llésions dnas la rate de trois chats parmi quatre-vingt sept autopsies effectuées dans le cadre d'une clientèle génárale. Ces iésions étaient dés métastases multiples d'un adénocarcinome dont la tumeur primitive siègeait dam la glande mammaire, une rupture de la rate et un corps érangers sou capsulaire. Zusammenfassung— Läsionen der Milz wurden bei vier von dreiuiidsechzig in dieser hbteilung sezierten Katzen gefunden, und zwar in zwei Fällen ein Lymphosarkom, in einem Falle eine chron-ische fibrinöse Peritonitis und in einem ein subkapsuläres Hématom. Anomalien fanden sich auch in der Milz von zwei Katzen, die aus der tierxrztlichen Praxis eingesandt wurden. Bei der einen Katze war dies ein Hämangiosarkom mit Metastasen in der Leber, bei der anderen eine weitläufige Infiltration der Mastzellen. Außerdem wurden bei drei von siebenundachtzig in der Praxis sezierten Katzen Milzläsionen gefunden. Diese bestanden am multiplen Metastasen eines Adenokarzinoms der Brustdrüse, einer Milzzerreissung und einem Fremdkörper unterhalb der Milzkapsel. 相似文献