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1.
养蜂业是受气候因素影响较大的农业副业，如果出现洋槐花期连绵阴雨、荆条花开花前期干旱等恶劣天气将造成蜂产品的严重减产，风险较大。同时，由于长期野外作业，遇到冰冻、洪水、泥石流等灾害性天气以及森林火灾、水源污染、大规模农药播撒等人为因素造成的灾害都会对蜂业生产造成巨大的损失，严重的甚至造成人员伤亡。 相似文献
2.
春季气温变化无常,易出现雨雪、风暴等极端天气,气候干燥,空气湿度较小,且昼夜温差大,极易对种鸡健康、种蛋运输和储存以及孵化环境等造成不利影响,进而影响种蛋的孵化率。在春季孵化应重点做好以下几方面工作： 相似文献
3.
众所周知,在影响农业生产的自然因素中最主要的是气候因素。气候为农业发展提供了光、热、水等能量和物质,某地的气候因素往往决定了该地的种植制度。所以气候对农业生产起着绝对性影响。特别是最近异常气候发生很频繁,使农民遭受很大的损失和极大的痛苦。 相似文献
4.
随气候变暖,仔畜成活率呈上升趋势,牲畜死损率呈下降趋势。冬季气温对牛犊成活率是主要气候影响因子,暖冬成活率高,冷冬成活率低;盛夏最低气温的变化影响牧草的生长状况,进而影响到牛群抓膘;初冬和晚冬牛群在自然游牧环境下,极端低温天气对牛群膘情的影响十分明显;秋末降水量多,冬季易形成坐冬雪使冬季放牧采食的牛群掉膘严重。初秋日照充足羊易增肥,寡照多雨羊易掉膘;初冬在自然游牧环境下,母羊产羔和羊群膘情受极端低温天气影响明显。气候生态因子通过逐步回归筛选,其影响程度通过通径系数分析用数量表达,由此建立的预测模型就更接近实际情况,对指导畜群生产及合理安排畜群结构提供科学依据。 相似文献
5.
我地区冬季跨度长,气候寒冷,平均每年最低气温达到-20℃左右,温差在-10℃左右,风雪天气较多,这样的天气就给我地区的畜禽养殖业带来了一定的不利影响,据不完全统计我地区每年因气候和风雪天气给畜牧业带来的损失大约达到30余万元,为了避免和减少因气候和恶劣环境造成的损失,笔者根据多年的深入基层工作实际,总结出以下六项措施确保我地区畜禽安全越冬,仅供广大养殖户参考. 相似文献
6.
一、天气和气候对肉质的影响 Berg,Butterfied,Gowling等人就天气和气候对牛肉质量的影响进行了一些研究,过去曾有人报导,赤道地区的牛,特别是由于缺乏照料和管理而处于热应激条件下的牛,肉质很差,不适合作食用。在那些条件下生产的牛肉,一般是粗糙而坚韧的。 相似文献
7.
1环境气候
母羊的生殖机能与日照、气温、湿度、饲料成分的变化以及其他外界因素都有密切关系,这些因素可以协同影响母羊的发情。尤其,羊卵泡的发育过程受季节和气候影响大,发情母羊数也与天气的阴晴有关。 相似文献
8.
饲养管理不当,繁殖技术不良以及环境因素异常等均会导致母羊发生繁殖障碍,影响其繁殖性能的发挥。 1 环境气候性不育母羊的生殖机能与日照、气温、湿度、饲料成分的变化,以及其它外界因素都有密切关系。这些因素可以协同影响母羊的发情。尤其,羊卵泡的发育过程受季节和天气影响大,发情母羊数也与天气的阴晴有关。 相似文献
9.
在气候和环境变化较为明显的天气状态下,容易由于病菌的大量繁殖对仔猪产生影响,使得其免疫力出现下降,而此时天气原因可能诱发猪瘟等病菌大量滋生,最终使得仔猪出现混合感染的现象。感染发生后威胁其生命安全,且具有传染性,对此我们采用不同方法对其分析,做出鉴别并探究其治疗情况。 相似文献
10.
秋季具有气温逐步下降、天气干燥、昼夜温差大等气候特点,环境控制不好,容易造成整齐度下降、孵化率下降等。针对这些特点结合多年孵化经验,将秋季孵化总结归纳为四句话:种蛋保存是基础,外环境稳定最关键,内环境稳定是保证,卫生防疫做后盾。 相似文献
11.
In late December 1983, 2 800 veterinarians across Canada were sent a questionnaire in order to assess the status of heartworm disease in Canada in 1983 and 26% of them responded. Veterinarians reported that 59 504 dogs were blood-tested to check for microfilariae and 771 dogs (1.30% of those tested) were found with Dirofilaria immitis. Heartworm disease was diagnosed in all provinces except New Brunswick and Newfoundland but most (733) of the cases were in Ontario. Heartworm disease was found most frequently in companion dogs over three years of age maintained mainly outdoors in rural areas. About 31% of the cases were observed with clinical signs of heartworm disease and 64% had a history of not having left Canada. Southwestern Ontario continues to be the focus of the infection and most of the dogs there had not left the province previously. 相似文献
13.
In late December 1985, 1485 institutional veterinarians and small and mixed animal clinics across Canada were sent a questionnaire in order to assess the status of Dirofilaria immitis in Canada in 1985 and 44% of them responded. Veterinarians reported that 137,300 dogs were blood-tested to check for microfilariae and 1210 dogs were found with heartworm. Another 36 dogs were amicrofilaremic but diagnosed with heartworm disease to give the total number diagnosed in 1985 as 1247 (0.91%). Heartworm was reported from all provinces except Prince Edward Island, Newfoundland and Saskatchewan but most (1126) of the cases were in Ontario. Southwestern Ontario continued to be the primary focus of the infection in Canada. From Quebec, 91 cases were reported mostly from and around Montreal. From Manitoba, 19 cases were reported from Winnipeg and surrounding areas. Heartworm was found most frequently in companion dogs over three years of age maintained mainly outdoors in rural areas. About 28% of the cases were observed with clinical signs of heartworm disease and 78% had a history of not having left Canada. 相似文献
14.
In late November 1988, 1581 small and mixed animal clinics and institutional veterinarians across Canada were sent a questionnaire in order to assess the status of Dirofilaria immitis in Canada in 1988, and 46% of them responded. Veterinarians reported that 181,577 dogs were blood-tested for heartworm disease and 367 dogs were found with D. immitis microfilariae. Another 60 dogs were amicrofilaremic but diagnosed with heartworm disease to give the total number of cases diagnosed in 1988 as 441 (0.24%). 相似文献
15.
In late December 1984, 1853 institutional veterinarians and small and mixed animal clinics across Canada were sent a questionnaire in order to assess the status of Dirofilaria immitis in Canada in 1984 and 35% of them responded. Veterinarians reported that 97,794 dogs were blood-tested to check for microfilariae and 1417 dogs (1.45% of those tested) were found with heartworm. Another 34 dogs were amicrofilaremic, but were diagnosed as having heartworm disease, to give the total number diagnosed in 1984 as 1451 (1.48%). Heartworm was reported from all provinces except Prince Edward Island and Newfoundland but most (1310) of the cases were in Ontario. In Quebec, 126 cases were reported mostly from west of Montreal. Heartworm was found most frequently in companion dogs over three years of age maintained mainly outdoors in rural areas. About 27% of the cases were observed with clinical signs of heartworm disease and 72% had a history of not having left Canada. Southwestern Ontario continued to be the primary focus of the infection. 相似文献
17.
In late November 1991, 1883 clinics in Canada were sent a questionnaire to assess the status of Dirofilaria immitis in dogs in 1991 and there was a 60.0% response. There were 344,031 dogs tested for heart-worm (HW), 627 were found infected and the prevalence of HW infection was 0.18%. There were 417 dogs with HW in Ontario, 116 in Manitoba, 38 in Quebec, 53 in British Columbia, three in Alberta, and one in Nova Scotia. In British Columbia, all of the infected dogs but one were from the Okanagan valley which, as from 1991, is a new focus of infection in Canada. Most dogs with HW had not been on preventive medication in 1990, and the prevalence among dogs tested and unprotected was 0.59%. That prevalence was considerably higher in endemic areas. Companion dogs, over three years of age and maintained primarily outdoors in rural areas, were most frequently infected. One cat was diagnosed with D. immitis and 33 dogs had Dipetalonema reconditium. 相似文献
18.
In late November 1989, 1732 clinics and institutional veterinarians were sent a questionnaire to assess the status of Dirofilaria immitis, and 51.7% responded. Of 247,716 dogs tested, 394 had D. immitis microfilariae and 51 were amicrofilaremic for a total of 445 cases and heartworm prevalence of 0.17%. Most (408) of these dogs had no preventive medication and the prevalence among dogs tested and unprotected was 1.01%. That prevalence was considerably higher in endemic areas. Thirty-seven dogs with heartworm had preventive medication. Heartworm was most frequent in companion dogs over three years of age maintained outdoors in rural areas. About 75% of the cases had never left Canada, 26% had clinical signs and 125 were not treated. Heartworm was reported from British Columbia, Manitoba, Ontario, Quebec, Nova Scotia and Newfoundland, but 383 cases were in Ontario. South-western Ontario was the primary focus of infection. There were 33 cases in Quebec and 24 in Manitoba, mainly found in and around Metropolitan Montreal and Winnipeg respectively. 相似文献
19.
In late November 1987, 1246 institutional veterinarians and small and mixed animal clinics across Canada were sent a questionnaire in order to assess the status of Dirofilaria immitis in Canada in 1987, and 50% of them responded. Veterinarians reported that 165,428 dogs were blood tested for heartworm disease and 511 dogs were found with D. immitis microfilariae. Another 78 dogs were amicrofilaremic but diagnosed with heartworm disease to give the total number of cases diagnosed in 1987 as 589 (0.35%). 相似文献
20.
In late December 1986, 1224 institutional veterinarians and small and mixed animal clinics across Canada were sent a questionnaire in order to assess the status of Dirofilaria immitis in Canada in 1986; 46% of them responded. Veterinarians reported that 150,989 dogs were blood-tested for microfilariae and 869 dogs were found with heartworm. Another 65 dogs were amicrofilaremic but diagnosed with heartworm disease and one was found with heartworm at necropsy to give the total number diagnosed in 1986 as 935 (0.62%). Heartworm was reported from Manitoba, New Brunswick, Ontario and Quebec, but most (810) of the cases were from Ontario. South-western Ontario continued to be the primary focus of the infection in Canada. There were 103 cases reported from Quebec, mostly from and around Montreal, and 21 cases from Manitoba, from Winnipeg and surrounding areas. Heartworm was found most frequently in companion dogs over three years of age maintained mainly outdoors in rural areas. About 33% of the cases were observed with clinical signs of heartworm disease and 81% had a history of not having left Canada. 相似文献
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