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41.
Sixty of the 65 dairy farms with cubicle houses in the Norwegian county of Oppland were included in a field study of the management of calving in 1990. The farmers recorded the location of the cow when giving birth, farmer presence and whether assistance was given during calving, occurrence of suckling, and time after birth when cow and calf were separated. Such data were recorded for a total of 1125 calvings. About 10% occurred on pasture, while 78% of the remaining calvings took place in the cubicle-equipped section. Thirteen percent calved in a calving pen, the remaining cows being tethered at the time of calving. Thirty-two percent of the calvings took place in houses lacking a calving pen altogether. Farmers were present during 41% of the calvings. Suckling most frequently occurred after pasture calvings, and was least frequent after calvings within the cubicle-equipped section of the cowhouse. Injuries to the calf caused by trampling or contact with fittings etc. were rare, and no more common in association with calving in the cubicle-equipped section than with calving taking place with the cow isolated from the rest of the herd. All calves were removed from their dams within 24 h after birth.  相似文献   
42.
亚硝酸盐中毒(Nitrite poisonig)是畜禽常发生的一种中毒病。用白菜等含硝酸盐较多的菜类作猪的饲料,因调制加工不合理,会产生大量的亚硝酸盐,喂后引起猪急性中毒,常来不急抢救而死亡,对养猪业危害较大。用食用醋精加入调制白菜的浸泡液中,使其pH值为4时,完全可抑制反硝化细菌的活动,基本上不会产生亚硝酸盐。这是因为醋酸是含有2个碳原子的有机酸,对反硝化细菌毒性大,使菌体内DNA和ATP受到破坏,细菌失去脱氮作用所致。用醋精作调制白菜的抑制剂,会起到预防畜禽亚硝盐中毒的作用。  相似文献   
43.
世界农业由子实体向营养体的转型、北方休牧还草政策的出台以及南方理想的自然条件和市场空间,为草畜业发展提供了千载难逢的机遇;南方发展草畜业不失为一条帮助农民快速致富的有效途径;只要破解观念更新、资金筹措、技术传授三大难题,草畜业定能成为南方农业的主要板块。  相似文献   
44.
Two questionnaire surveys (2×44) were conducted among pastoral households, using three grazing management systems. The average number of Tropical Livestock Units (250 kg) was 4.0 per member of the household. Milk production was the most important source of revenue (66% of the total) followed by sale of livestock (17%) and transport (16%). High mortality rates were recorded for all livestock. About 27% of the milk was sold fresh or as butter. Sedentary and transhumant grazing management systems showed similar levels of income, but nomads had a 2.6-fold higher overall net income. The average total gross income from the entire herd amounted to US$ 6382 per household per year. The calculated costs were 29% of the gross returns. The contribution to the total gross revenues of camels, cattle and small ruminants was 58%, 25% and 17%, respectively.  相似文献   
45.
本文介绍了丹麦有机猪的生产情况(有机猪的品种、畜舍环境和条件、畜舍卫生和饲养饲料状况)、沙门氏菌控制计划的情况(饲料、种猪群、断奶仔猪群、育肥猪群和屠宰场的监控)和效果。同时,简析了我国发展有机畜牧业的必要性,最后提出实行危害分析和关键控制点(HACCP)预防管理体系和有机养殖是我国养猪业的发展方向。  相似文献   
46.
随着我国养猪业的快速发展,猪病的发生率不断上升,对环境的污染不断严重,猪肉产品的质量也在不同程度上存在一些问题,影响了养猪业的可持续发展和人的健康。为实现养猪业安全、优质、高效和无公害生产,必须实施猪的健康养殖。本文提出了实现猪健康养殖的对策。  相似文献   
47.
本文运用灰色建模理论中的灰色数列预测方法,利用北京密云县10个乡镇的畜禽粪便实际负荷量和最大负荷量的确定,对未来年份的畜禽粪便负荷预警值进行预测。结果表明:该流域各乡镇未来十年所受畜禽粪便的污染威胁均呈现逐年加剧趋势,其中石城和番字牌预警值上升最快;冯家峪、大城子和新城子次之,高岭、太师屯和不老屯呈现缓慢上升态势。  相似文献   
48.
植酸酶是一种新型饲料添加剂,它能提高动物对饲料中植酸磷的利用率,降低粪便中磷的排泄量。本文对植酸的化学结构、理化性质与植酸酶的来源、生物学特性,并对影响植酸酶活力的因素及其在畜禽生产中的最新应用研究作了简要介绍。  相似文献   
49.
In a 2 × 2 factorial arrangement, 16 groups of 12 pigs were assigned to one of two housing systems (straw bedding, S vs. Barren, B) and to one of two starch types (native, N vs. pregelatinized potato starch, P, each included at 35%) to study effects on apparent faecal digestible nutrient intakes. Intake of straw from bedding material was estimated, using several markers, and results are discussed. Straw intake of the S-pigs was estimated between 143 and 234 g DM/d for P-pigs and between 96 and 156 g DM/d for N-pigs, depending on the method used. Nutrient digestibility was reduced in N-pigs when compared with P-pigs. Intake of digestible dry matter, energy, starch and ADF was increased in S-pigs, but the intake of digestible protein was reduced. Despite greatly reduced nutrient digestibility in S-pigs, additional digestible nutrient intake due to housing on a straw bedding can be considerable.  相似文献   
50.
酶制剂作为3大绿色饲料添加剂(益生素、中草药、酶制剂)之一,能够部分解决饲料资源不足的难题,它的研究、开发与应用已成为动物营养界关注的一个热点;作者综述了酶制剂在畜牧生产应用中的最新研究进展,并初步提出酶制剂开发利用的研究重点。  相似文献   
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