共查询到20条相似文献，搜索用时 172 毫秒
1.
辽宁省北宁市的肉鸡产业发展较快，根据统计，全市村外养殖小区270个，规模养殖户1．3万户，年出栏肉鸡4000多万只，形成了本市经济发展和农民致富奔小康的支柱产业。最近，笔者随着科技三下乡技术咨询团深入到各乡镇肉鸡养殖小区和规模养殖大户，对养殖户普遍反映的鸡病多、投药多、育成率低的问题进行了调查和综合分析。 相似文献
2.
3.
近年来，畜牧业生产迅猛发展，出现了大批的规模化养殖场和养殖小区，而无公害肉鸡的规模化生产更显良好势头，就姜堰市而言，年出栏2000只以上的肉鸡养殖户就有559户，年出栏1000万只以上。但规模化肉鸡养殖所产生的粪便因含有大量有害物质和病原微生物，并散发恶臭，不进行有效处理则污染严重。因此，进行肉鸡规模养殖粪便处理和利用，使其无害化、减量化、资源化， 相似文献
4.
5.
6.
近几年来,随着肉鸡业的普遍发展,农村肉鸡养殖也越来也多,规模由小逐渐变大.然而,由于农村养殖户大多是利用自己空闲的房屋作为鸡舍,条件简陋,环境恶劣,不符合兽医卫生要求,另外养殖户缺乏安全饲养意识,管理技术跟不上,致使肉鸡的成活率低,疾病多,养殖效益少,严重影响了农村肉鸡业的发展. 相似文献
7.
8.
一 两广优质鸡养殖企业的现况
对于优质鸡主要养殖地——广西、广东来讲,方圆41万多平方公里,现有200多家规模大小不一的养殖企业,规模养殖户大约达10．7万户。最大的企业年产值达上百亿元人民币,小规模企业的年产值也有数十万元人民币。但是,两广整体养殖基数是巨大的。综合广西、广东两省发展情况,2006年种鸡存栏1850多万套,2007年达到了2200多万套;2006年肉鸡出栏12．5亿羽,2007年则为15亿羽; 相似文献
9.
10.
11.
12.
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
13.
14.
15.
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
17.
18.
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
19.