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93.
京海黄鸡杂交组合亲本鸡球虫抗性指标的比较 总被引:1,自引:1,他引:0
为研究京海黄鸡杂交组合亲本BB鸡与FF鸡鸡球虫病抗性的差异,试验选取BB和FF公鸡各30只,饲养至9日龄时,每个群体随机分为免疫组(n=15)和非免疫对照组(n=15),分组当天免疫组京海黄鸡杂交组合亲本按正典鸡球虫病四价活疫苗说明书要求接种鸡球虫疫苗,疫苗免疫后第8天采用生物素双抗体酶联免疫吸附法(ELISA)测定免疫组和非免疫对照组8个血浆球虫抗性指标,并进行差异显著性检验.结果显示,BB鸡免疫组过氧化氢酶(CAT)、超氧化物歧化酶(SOD)和白介素17(IL-17)的含量显著高于FF鸡免疫组(P <0.05);BB杂交组合亲本免疫组CAT含量极显著高于对照组(P <0.01),SOD含量显著高于对照组(P <0.05);FF杂交组合亲本免疫组CAT和谷胱甘肽过氧化物酶(GSH-Px)含量均显著高于对照组(P <0.05).综合分析结果表明,BB鸡免疫效果优于FF鸡群体,BB鸡球虫病抗性优于FF鸡群体. 相似文献
94.
针对奶牛养殖快速发展带来的资源浪费和环境污染问题,探讨了南方规模化奶牛场循环农业模式并提出了相关策略。提出养殖场粪污(包括奶牛粪、尿和养殖废水)是造成环境污染的主要因子,牧草是消纳养殖场粪污,变废为宝,构成循环利用链的主要载体。因此南方规模化奶牛养殖可以就地取材、就近利用,构筑形成草基循环农业模式。草基循环农业模式结合规模化奶牛养殖对鲜草需要量大、杂交狼尾草产量高且对奶牛场污水氨氮吸收率高的三大因素而构建,是低耗高效、安全优质、清洁生态的循环农业模式。 相似文献
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Khan HA Siddique M Arshad M Abubakar M Akhtar M Arshad MJ Ashraf M 《Tropical animal health and production》2009,41(4):427-430
A total of 70 sheep and 330 goats were selected randomly. All the animals were kept under same housing and management conditions.
Serum samples were collected from all the animals and tested for the presence of antibodies against Peste des petits ruminants
(PPR) virus using competitive ELISA (cELISA). All the animals were found negative showing percentage inhibition (PI) values
<50. The animals were vaccinated against PPR with Nig/75/1 strain vaccine of PPR Serum samples were collected from randomly
selected 12 sheep and 30 goats at 10, 30 and 45 days post-vaccination. The samples were subjected to cELISA to determine the
presence of antibodies against PPRV. The samples with PI >50 were considered as sero-positive. The sheep found positive at
10, 30 and 45 days post-vaccination were 1(8.3%), 7(58.3%) and 12(100%) respectively. In case of goats 3(10.0%), 29(96.6%)
and 27(90.0%) animals gave positive results at 10, 30 and 45 days post-vaccination respectively. Mean PI values in sheep at
10, 30 and 45 days post-vaccination were recorded as 37, 65 and 91 respectively, whereas in goats these values were 43, 78
and 86 respectively. 相似文献
97.
Xiaokai Song Lixin XuRuofeng Yan Xinmei HuangMohammed Ali A. Shah Xiangrui Li 《Veterinary parasitology》2009
The immunization procedure of DNA vaccine pcDNA–TA4–IL-2 of Eimeria tenella, including route, dose, time of immunization and age of primary immunization of chicken, was optimized. The stability and the cross-species protection of the vaccine were also analyzed. Efficacy of immunization was evaluated on the basis of oocyst decrease ratio, lesion score, body-weight gain and the anti-coccidial index (ACI). Chinese Yellow chickens were randomly distributed into corresponding groups (30/group). The challenged, unchallenged and vector control groups were designed. The results illustrated that 25 μg was the optimal dose and intramuscular injection was the most effective route to induce protective immunity. There were no significant differences of ACIs between boosting and non-boosting groups. Storage time and temperature had little effect on the immunizing efficacy of the vaccine. The vaccine could provide partial cross-protection against the challenge with E. necatrix and E. acervulina, but not with E. maxima. 相似文献
98.
Proliferative enteropathy (PE) is an enteric disease of pigs that results in diarrhoea, reduced growth rate, reduced feed conversion efficiency and sometimes death. A survey of 13 pig veterinary practitioners in Australia was conducted to determine: (1) PE control strategies (antibiotics and vaccination), (2) how the efficacies of these strategies are evaluated and (3) how reliance on antibiotics could be reduced by increasing vaccine adoption. Antibiotics were routinely prescribed in the diets of weaner, grower and finisher pigs by 9/13, 10/13 and 8/13 veterinarians, respectively, if vaccination was not implemented. Water-soluble antibiotics were prescribed less frequently than in-feed antibiotics. Efficacy of control strategies was assessed most often through reduced clinical signs (diarrhoea, 'tail-ender' pigs, death) and reduced lesion incidence at abattoir postmortem inspection. Twelve practitioners had recommended PE vaccination to their clients in the previous 6 months. Barriers to continued vaccine implementation included perceived lack of efficacy for pigs housed in bedded systems, high cost relative to medication and difficulties in vaccinating pigs post-weaning. 相似文献
99.
枯叶蛱蝶规模化人工繁育研究 总被引:4,自引:0,他引:4
通过对成虫繁殖的空间条件、补充营养、卵期保育和幼虫饲育技术等的研究,找出了枯叶蛱蝶规模化繁育中的关键条件.在2头/m2的成虫密度条件下,雌蝶在一个高3 m、占地50 m2的网室空间内平均产卵量达到2457粒;10%~20%蜂糖水溶液能满足成虫营养需要,雌蝶平均产卵量为236.8~243.3粒;在蜂糖水中加入5%乙醇后,雌蝶平均产卵量最高达到279.8粒;将每日产下的卵收集起来在小玻璃瓶内保育,在卵临近孵化时将小瓶夹在寄主叶片附近;幼虫1~2龄期间在室外寄主上套袋放养,放养虫口密度为100~150头/袋;3~5龄期在室内饲养,饲养密度为600~800头/m\+2,室内温度控制在19~28℃;健康蛹不需要附着在物体下亦能正常羽化,但不宜在低温下贮存. 相似文献
100.