四氯联苯对鸡胚性腺原始生殖细胞的毒性影响

采用四氯联苯处理发育至Ⅹ期的白来航鸡种蛋,孵化5.5天后取出胚胎进行全固定,用石蜡切片和PAS染色(高碘酸希夫试剂)研究四氯联苯对鸡胚性腺原始生殖细胞(PGCs)的影响.结果表明,四氯联苯对发育至5.5日胚龄的鸡胚性腺PGCs数量和结构有明显影响,但雌二醇处理的5.5日胚龄鸡胚PGCs数量变化不显著,其结构无明显变化.表明四氯联苯对5.5日胚龄的鸡胚性腺PGCs的影响主要来自于其毒性作用.     

银合欢对肉鸡临床毒性及减毒的研究

为研究银合欢对肉鸡的临床毒性和减毒作用,250只10日龄AA肉鸡随机分为五组,每组50只.在试验组的日粮中分别添加5%,10%,20%的银合欢进行试验,为期50天.通过对肉鸡生产性能,血液激素水平和粪中含羞草素含量的测定,结果显示适量添加银合欢可增加平均日增重,平均日采食量,减低饲料消耗率.银合欢的安全添加量应不超过饲料量的5%.     

Paraoxonase activity as a tool for clinical monitoring of dogs treated for canine leishmaniasis

This study was designed to determine if the activity of paraoxonase (PON1), an antioxidant enzyme that works as a negative acute phase reactant, is a better predictor for the clinical recovery of leishmaniotic dogs receiving standard treatments compared with inflammatory markers such as C reactive protein (CRP) and electrophoretic fractions. For this purpose we tested 20 healthy dogs (controls) and 39 leishmaniotic dogs classified as sick (group A, n = 23) or severely sick (group B, n = 16) and tested at admission and after 3, 7, 14, 21, 28, 35 and 42 days.At admission, CRP and electrophoresis were altered in both groups, while PON1 activity was abnormal only in group B. There were no differences related to the outcome (mortality, complications or time of recovery). PON1 activity normalized in about 2 weeks in dogs that had abnormal values at admission and a final positive outcome; CRP normalized in 4–6 weeks and electrophoretic fractions were still altered after 6 weeks. The results show that, at admission, inflammatory markers did not predict the outcome of leishmaniasis. PON1 activity decreased only in some dogs with systemic inflammation but not in those with mild leishmaniasis: when decreased, PON1 normalized earlier than other markers in dogs that responded to treatment. This finding most likely depends on the rapid decrease in oxidative phenomena. PON1 activity should therefore be tested on admission: if low values are recorded, severe inflammation may be suspected and PON1 measurement may be repeated during treatment to early identify responsive dogs.     

乳中硫氰酸盐对人类健康的风险评估

全面综述了乳中硫氰酸盐对人类健康的风险。介绍了硫氰酸盐在生鲜乳中保鲜使用情况,乳中硫氰酸盐的正常生理浓度和检测方法,乳及人体内硫氰酸盐的来源和影响因素,乳中硫氰酸盐对人类健康的毒性作用及风险评估。     

Acute phase response in mice experimentally infected with Trypanosoma congolense: a molecular gauge of parasite-host interaction

Mice infected with Trypanosoma congolense developed a severe anaemia 1 week after infection, which persisted till treatment with diminazine aceturate when the packed cell volume (PCV) recovered to pre-infection levels. This was accompanied by a marked increase in the plasma levels of the acute phase proteins (APP), serum amyloid P-component (SAP) and haptoglobin (Hp). The initial peak levels of Hp and SAP were attained 7 and 12 days post-infection (DPI), respectively. Thereafter SAP levels decreased significantly to near pre-infection levels, but later increased even after treatment to give a second peak 34 DPI after which there was a decline till the study was terminated. The Hp levels on the other hand decreased to an intermediate level after the initial peak increasing to a second peak 22 DPI. Thereafter Hp decreased significantly following diminazine aceturate treatment to reach pre-infection levels within 5 days post-treatment. This indicates that T. congolense-infected mice develop severe anaemia accompanied by an acute phase response leading to an increase in SAP and Hp but that following treatment divergent responses occurred indicating differences in the pathways for stimulation of the APP. Haptoglobin was shown to be an earlier indicator of infection and a better marker in monitoring the response to treatment.     

Permethrin toxicity in cats: a retrospective study of 20 cases

OBJECTIVE: Permethrin is a synthetic pyrethroid widely used in flea control products for small animals. Accidental toxicity can occur with off-label usage, and cats are particularly susceptible. METHODS: Retrospective study of 20 cases of permethrin toxicity in cats treated at an emergency clinic in Brisbane, Queensland from October 2004 to June 2005. RESULTS: The diagnosis of permethrin toxicity was made on the basis of a history of exposure and characteristic clinical signs, including seizures, muscle fasciculations, and tremors. Decontamination and appropriate seizure or muscle fasciculation control were the basis of treatment. The outcome was good after rapid intervention and 19 of the 20 cats were successfully treated, with the only death occurring in a kitten for which treatment was delayed for 24 h. No long-term complications were reported by the cats' owners at 4-month follow-up after discharge from hospital. CONCLUSIONS: Owner education, together with more appropriate product labelling, may help eliminate this problem in the future.     

7种杀菌剂对大麦条纹病的防治效果

针对大麦条纹病,选用7种杀菌剂对大麦品种甘啤4号种子处理后进行了室内毒力测定和室内发芽测定,同时进行了大田试验。结果表明,10％二硫氰基甲烷乳油,37／6敌萎丹悬浮种衣剂和0．5％二硫氰基甲烷种衣剂具有较好的抑菌效果,其EC。。有效抑菌浓度为2．563、7．345和19．721μg／mL;10％二硫氰基甲烷乳油、8％克...     

藏草乌水煎提取液体外杀灭羊虱蝇药效及皮肤毒性试验研究

试验旨在研究藏草乌的水煎提取液在体外杀灭羊虱蝇的药效作用及其皮肤毒性、刺激性、过敏性试验,为藏草乌的开发利用和临床应用提供理论依据。将1%、2%、4%、8%、10%藏草乌水煎提取液分别滴于衬有吸水纸和羊虱蝇的平皿中,在1、2、4、8 h时分别观察其对羊虱蝇的杀灭情况。取相同剂量1%、2%藏草乌水煎提取液均匀涂于大白兔的完整皮肤和破损皮肤,进行皮肤毒性、刺激性和过敏性试验。结果显示,给药1 h后各浓度的藏草乌水煎提取液及阳性对照组均出现了不同程度的羊虱蝇杀灭效果,4 h后阳性对照组杀灭率为100%,8 h时,1%、2%藏草乌水煎提取液杀灭率达到70%,而2%藏草乌水煎提取液较1%药物组杀灭羊虱蝇效果好;皮肤毒性试验显示,大白兔皮肤无红斑、水肿,体重变化正常;皮肤刺激性试验结果显示,藏草乌提取液对大白兔皮肤无刺激性;皮肤致敏反应结果表明,藏草乌提取液对大白兔不具有致敏性。综上所述,藏草乌水煎提取液具有良好的体外杀灭羊虱蝇作用,且皮肤用药安全。