福建黄兔繁殖性状相关研究

本文对３１０只母兔的繁殖性状进行了测定分析，结果表明；妊娠期与产仔数、产活仔数及活仔窝重呈负相关，相关系数分别为－０．４２６＊、－０．３５０＊和－０．５１５头４胎内母兔，胎次对产仔性能无影响，对母兔泌乳性能有一定影响。同样条件下胎次增加。泌乳性能提高，第３胎较第２胎有显著提高。     

不同周龄大耳白兔血液生理生化指标的测定

为了明确大耳白兔中国兽药监察所封闭群的生物学特性，对其血液生理生化指标进行了测定。选5、10及13周龄的雄兔和雌兔。空腹采血测定红细胞、白细胞等16项血液生理指标和血糖、总蛋白等16项生化指标。10周龄的红细胞数、白细胞数、红细胞压积和平均红细胞血红蛋白含量高于5周龄和13周龄，雌雄间血液生理指标无明显差异，血清丙氨酸转氨酶含量随着周龄的增加而升高，碱性磷酸则随着周龄的增加而下降。与日本大耳白兔相比，主要血液生理指标比较接近，丙氨酸转氨酸、白蛋白、尿素氮、直接胆红素等血液生化指标相近，其他指标有所不同。测定结果表明，该封闭群具有不同于日本大耳白兔（Slc:JW/CSK)的生物学特性。     

兔病毒性出血症鸡源高免蛋黄抗体的研究与应用

用兔病毒性出血症抗原免疫产蛋鸡,收集高免蛋,精制蛋黄抗体(IgY),采用血凝抑制试验(HI)测定IgY的最高滴度为15 1og2.通过IgY的被动免疫保护试验证实,IgY滴度稀释至13 1og2时肌肉注射体重2.0～2.5kg的健康非免家兔5.0mL/只,可抵抗兔病毒性出血症强毒RC株1.0mL(血凝价HA为9 1og2)的攻击.临床应用效果显示:IgY(HI为13 log2)对发病兔进行紧急防治,治愈率为84.38%～92.86%,能迅速控制疫情.     

Enantioselective degradation kinetics of metalaxyl in rabbits

Metalaxyl [methyl-N-(2′-methoxyacetyl)-N-(2,6-dimethylphenyl)-d,l- alaninate] is a potent phenylamide fungicide. The (−)-(R)-isomer accounts for most of the fungicidal activity. A possible stereo and/or enantioselective kinetics of metalaxyl in rabbits was investigated by intravenous injection. The concentrations of (−)-(R)- and (+)-(S)-metalaxyl in plasma, liver, and kidney tissue were determined by HPLC with a cellulose-Tris-(3,5-dimethylphenylcarbamate)-based chiral stationary phase and gas chromatography-mass spectroscopy. After intravenous administration of racemic metalaxyl (40 mg/kg), the (+)-(S)-enantiomer levels in plasma, liver, and kidney decreased more rapidly than the (−)-(R)-isomer. The area ratio of the (−)-(R)-/(+)-(S)-enantiomer under the concentration-time curve (AUC_0 → ∞) in plasma after drug application was 1.62. The total plasma clearance value of the (+)-(S)-enantiomer was 1.53 and higher than that of the (−)-(R)-enantiomer. The [R]/[S] ratio in plasma was >1 for standard rac-metalaxyl at each time point. The other pharmacokinetic parameters of the enantiomers were also different. The results indicate substantial stereoselectivity in the degradation of metalaxyl enantiomers in rabbits.     

兔病毒性出血症、多杀性巴氏杆菌病、产气荚膜梭菌病(A)型三联灭活疫苗研制

对 5批兔病毒性出血症、多杀性巴氏杆菌病、产气荚膜梭菌病三联灭活疫苗进行了动物试验 ,结果表明该疫苗安全有效。近期效检对兔病毒性出血症的保护率为 1 0 0 % ,对兔多杀性巴氏杆菌病保护率为 92 % ,对产气荚膜梭菌病 (A)型保护率为 88%。在免疫期试验中 ,免疫 6个月后 ,对兔病毒性出血症保护率为 1 0 0 % ,对多杀性巴氏杆菌病的保护率为 79% ,对产气荚膜梭菌病 (A)型的保护率为 88%。在保存期试验中 ,4～ 8℃保存 1年仍有效。     

Non-target toxicology of a new mosquito larvicide, trypsin modulating oostatic factor

Trypsin modulating oostatic factor (TMOF), a peptide hormone originally isolated from the ovaries of adult Aedes aegypti, is currently under commercial development as a new pesticide chemistry with a novel mode of action for the control of larval mosquitoes. The objective of the current research is to evaluate potential risks of the use of TMOF as an insecticide on non-target organisms. TMOF (YDPAP₆) was degraded in vitro (as determined by HPLC and LC/MS) to DPAP₆, PAP₆, and then AP₆ by leucine aminopeptidase, a pancreatic enzyme found in the digestive system of vertebrates. The rate of degradation of TMOF and PAP₆ was significantly greater than that of DPAP₆, while no metabolism of AP₆ was found. TMOF technical insecticide was produced on a commercial scale by recombinant yeast (heat-killed before application). The technical TMOF when administered in a single dose by gavage to male and female mice at 2000 mg dry weight/kg body weight produced no negative effects as compared to controls up to 12 days after treatment. When male and female mallard ducks were treated by gavage with 1250 mg dry weight of technical TMOF/kg body weight each day for 5 days, again no toxic effects were noted through 35 days after the last treatment. TMOF technical insecticide was also applied to the shaved skin of male and female rabbits at the rate of 2000 mg/kg for 1-2 days, with no effect. The end point observations in these in vivo experiments were mortality; changes in growth rate, behavior, body structure, and color; and possible lesions observed during necropsy. Finally, Daphnia incubated with technical TMOF in rearing water at the level of 1.0 × 10⁶ yeast cells/ml (10 mg/ml) also demonstrated no negative effects on mortality, growth, molting, time to first brood, and production of viable neonates. It appears from these studies that TMOF can be degraded by vertebrate digestive proteases and technical TMOF is not toxic to the non-target organisms examined.     

兔出血症-巴氏杆菌病铝胶二联灭活苗的研制

筛选了具有良好免疫原性的兔瘟强毒株GMH881和兔巴氏杆菌C51-17株,研制出了兔出血症-巴氏杆菌二联铝胶灭活苗,对疫苗进行了免疫剂量、免疫产生期、兔出血症抗体测定、免疫保护期、保存期等试验;确定出二联铝胶苗免疫剂量1.0 mL;二联铝胶苗在免疫后7 d对兔病毒性出血症强毒的保护率达到100%,二联苗免疫后10～14 d对兔巴氏杆菌的保护率均达到75%以上;二联铝胶苗的兔病毒出血症抗体测定结果表明：二联铝胶苗免疫家兔后7 d,HI抗体均可达25.0,15 d明显上升,二联苗HI效价60～90 d达到最高峰,最高可达210,二联苗在120～180 d仍可维持在27.0～29.5水平。二联铝胶苗分别在免疫后4个月、6个月用兔出血症强毒攻击均产生100%保护,在6个月用2个MLD的兔巴氏杆菌攻击保护率可达70%以上,二联铝胶苗4～8℃条件下保护期暂定为1年,25℃条件下暂定为半年。     

牧草产业是我国家兔产业可持续发展的重要支撑

针对我国家兔规模化养殖的快速发展,牧草作为家兔生产主要饲料原料来源,供需矛盾日益突出。本文重点从家兔消化生理特点、兔产品安全生产、农民增收、需求现状与问题等方面进行了论述,并提出了相应对策。