Possible Fenthion Toxicity in Magpies (Pica pica)

Unusual mortality in magpies (Pica pica) is described. Dead or sick birds were discovered in proximity to cattle in Alberta feedlots. Subsequent examinations indicated magpies were being exposed to fenthion, an organophosphate used on cattle for control of warble larvae and lice. The possibility of toxicity with fenthion is suggested.     

毒死蜱对家蚕的急性毒性研究

在室内不同条件下进行了桑园杀虫剂毒死蜱对家蚕的急性毒性试验,结果表明:毒死蜱对2~5龄家蚕幼虫的摄入LC50值(48 h,25℃)分别为1.11、1.73、3.48与4.12 mg/L;在20、25、30、35℃下,毒死蜱对3龄家蚕的LC50值(48 h)分别为1.70、1.80、0.49与0.40 mg/L;桑叶浸药时间为1 s、10 s、1 m in、10 m in与1 h时,毒死蜱对4龄家蚕幼虫的LC50值(48 h,25℃)分别为5.55、3.64、3.15、2.12与1.54 mg/L;家蚕幼虫在毒死蜱药膜上爬行1、10、30与60 m in后,毒死蜱对3龄家蚕的接触LD50值(48 h,25℃)分别为3.59、0.28、0.20、0.12μg/cm2。     

Toxicity of Riddell's groundsel (Senecio riddellii) to cattle

The toxicity of Riddell's groundsel (Senecio riddellii) fed to calves in gelatin capsules, by gavage, or mixed in their hay ration was determined. Dosages were varied according to the pyrrolizidine alkaloid (PA) content of the plant, and the calves' responses were measured by clinical signs, serum enzyme changes, survival time, and histopathologic changes. Calves fed S riddellii to provide 10 mg of PA/kg of body weight/day in capsules or by gavage for 20 consecutive days did not develop clinical signs of seneciosis and did not have meaningful serum enzyme changes. However, feedings of the plant that provided 15 to 20 mg of PA/kg/day or more (gavaged or fed in capsules for the same time period) resulted in high mortality. The Senecio plant mixed in calves' hay ration was eaten slowly and reluctantly and was tolerated at dosages greater than 20 mg/kg/day, emphasizing that the toxicity was dependent on the rate at which the dosage was consumed and that mortality was not necessarily dependent on the cumulative dosage. Because of its high PA content, S riddellii presents a great hazard to cattle managed under conditions where they can consume quantities of the plant in short periods of time.     

玉米赤霉烯酮对猪卵巢颗粒细胞毒性的研究

以体外培养的猪卵巢颗粒细胞为模板,研究了玉米赤霉烯酮(ZEA)对该细胞的毒性作用.结果表明,在所测浓度范围内,ZEA对卵巢颗粒细胞活性具有明显的抑制作用,且抑制作用随着浓度的增强而加大,并呈现剂量效应关系;60、90和120 μmol/L的ZEA使细胞中的MDA含量均升高,呈现剂量效应关系;ZEA作用后,细胞中GSH-Px酶活力下降;TUNE检测发现凋亡细胞呈棕褐色,凋亡细胞间间隙明显加大,随着ZEA剂量的加大,棕褐色细胞逐渐增多,尤其是高剂量ZEA组,细胞核大部分被染成棕褐色,细胞皱缩,胞间几乎无连接;当Annexin标记FIFC、流式细胞仪检测发现,高剂量组(120 μmol/L) ZEA处理后其凋亡率可达60.83％,坏死率很低,显示ZEA抑制猪卵巢颗粒细胞增殖主要是通过细胞凋亡,并非坏死途径.     

Toxicity in goats caused by oleander (Nerium oleander)

Cases of poisoning by oleander (Nerium oleander) were observed in several species, except in goats. This study aimed to evaluate the pathological effects of oleander in goats. The experimental design used three goats per group: the control group, which did not receive oleander and the experimental group, which received leaves of oleander (50 mg/kg/day) for six consecutive days. On the seventh day, goats received 110 mg/kg of oleander leaves four times at one-hourly interval. A last dose of 330 mg/kg of oleander leaves was given subsequently. After the last dose was administered, clinical signs such as apathy, colic, vocalizations, hyperpnea, polyuria, and moderate rumen distention were observed. Electrocardiogram revealed second-degree atrioventricular block. Death occurred on an average at 92 min after the last dosing. Microscopic evaluation revealed renal necrosis at convoluted and collector tubules and slight myocardial degeneration was observed by unequal staining of cardiomyocytes. Data suggest that goats appear to respond to oleander poisoning in a manner similar to other species.     

水生物种中黄曲霉毒素的代谢及毒性研究(四)

<正>(上接第12期)3.5敏感性种类众多研究发现,在AFB1诱导肝癌的易感性方面,生物种间和种内存在着极大的差异(Eaton等,1990;Ramsdell和Eaton,1990;Hayes等,1991;Eaton等,1995),例如啮齿动物主要体现在大鼠对AFB1具     

高效灭蛀灵对毛皮害虫的效力与毒性试验

对高效灭蛀灵的药效、安全性、毒理进行测定。结果表明：高效灭蛀灵对各类毛皮及其制品主要害虫的各发育期均具有杀灭和预防作用，杀早率在99.47％－100％；防蛀效果达45个月；室温保存两年或煮沸、冷冻、日晒，药效均无明显变化；对各类毛皮及制品无腐蚀性，对人安全。应用效果证明，本品安全、高效、实用，有灭蛀、防蛀、防霉、消毒之功效，适宜于仓储、宾馆、家庭使用。     

MDMA(摇头丸)对小鼠LD50的测定及其毒性作用

MDMA(3,4亚甲基二氧甲基苯丙胺)属于苯丙胺类兴奋剂中的一种特殊类型,俗名“摇头丸”。该药传入我国内地之后成为严重危害人类健康的新型毒品。本文通过灌胃和腹腔注射两种方法测定MDMA的半数致死量(LD50),并研究它对小鼠的毒性作用。研究表明,MDMA对昆明系小鼠经灌胃给药的LD50为27.35mg/kg体重,腹腔注射的LD50为42.85mg/kg体重,试验鼠表现出高度兴奋、尖叫和冲撞,最后因呼吸麻痹而死亡。此研究有助于人们进一步认识该毒品的毒性作用及其对人体健康的危害。     

Toxicity of pyrrolizidine alkaloids from Riddell groundsel (Senecio riddellii) to cattle

The toxicity of Riddell groundsel (Senecio riddellii) gavaged to calves at a known lethal rate was compared with the toxicity of riddelliine and riddelliine N-oxide, the pyrrolizidine alkaloids isolated from the plant, which were fed by intraruminal infusion. Doses of the alkaloids were adjusted to the amount determined to be in the plant and fed individually and in combination. The relative toxicosis in the calves was measured by clinical signs, serum enzyme changes, survival time to morbidity, and histologic changes. Calves fed Senecio riddellii by gavage for 20 consecutive days to provide 45 mg of total pyrrolizidine alkaloids/kg of body weight/d developed clinical signs and serum enzyme changes typical of seneciosis, with 100% morbidity. However, calves receiving riddelliine at 4.5 mg/kg/d for 20 days had neither serum enzyme changes nor clinical signs of pyrrolizidine alkaloidosis. Calves treated with riddelliine N-oxide (40.5 mg/kg/d), and with riddelliine (4.5 mg/kg/d) and riddelliine N-oxide (40.5 mg/kg/d) in combination, had 100% morbidity, although the latter group had fewer liver lesions. These results establish that the N-oxide form of the alkaloid alone is capable of inducing typical Senecio toxicosis in cattle and that the free base level of the plant cannot be considered to be the sole factor in assessing the toxicity of S riddellii.     

瑞香狼毒根对长爪沙鼠的急性毒力测试

本文采用含17%瑞香狼毒(Stellera chamaejasme)根粉末的毒饵,依据孙氏改良寇氏综合计算法,实验室内测定了其对长爪沙鼠(Meriones unguiculatus)的急性毒力。根据预试验结果,采用最低剂量为7.0 g·kg^-1,最适剂量梯度比值K=0.65的5个剂量梯度的瑞香狼毒根毒饵饲喂长爪沙鼠。结果显示:试验组试鼠体重明显下降(P=0.029<0.05),完全致死组肝脏重/体重比对照组明显减小(P=0.014<0.05),但肾脏略增大(P=0.102>0.05)。其对长爪沙鼠的LD50为(20.37±0.086)g·kg^-1,95%平均可信限为(20.37±7.84)g·kg^-1,属弱毒水平。     

Dietary Vitamin D Toxicity in a Household of Pot-Beliied Pigs (Sus scrofa)

Vitamin D intoxication developed in Vietnamese Pot-Bellied Pigs ( Sus scrofa ) fed 2 commercially available swine rations. Pronounced hypercalcemia and a history incompatible with other causes of hypercalcemia led to confirmation of this diagnosis by plasma vitamin D metabolite analysis in 2 affected animals as compared to a control animal. Feed sample analysis suggested the diet as the likely source of toxicity.     

40%乐桑乳油对朱砂叶螨毒力测定的SPSS分析

应用SPSS软件中的Probit模块,统计分析了40％乐桑乳油对桑树朱砂叶螨的毒力测定数据,结果显示：应用SPSS进行毒力测定数据的统计具有快捷、直观、准确、输出信息量大的特点。     

Toxicity of Sevin (1-Naphthyl-n-Methyl-Carbamate) To Cattle Grubs, Lice, and Cattle

Sevin, a cholinergic insecticide, was used for the control of cattle lice Haemotopinus eurysternus and Bovicolar bovis and cattle grubs Hypoderma lineatum and H. bovis. Partial or complete spraying of the animal body with 0.5 per cent Sevin was equally effective for louse control and one application killed the lice and prevented reinfestation in `carrier' cows for 17-20 weeks.

The dermal or parenteral administration of Sevin to the host animal had no larvicidal effect on cattle grubs migrating in its body. Similarly, the sprays of Sevin had no lethal effect on grubs encysted in the back of cattle.

     

Acute,Oral Toxicity to Laboratory Animals of Fenthion (O-O-Dimethyl-O-(3-Methyl-4-Methyl-Mercapto-Phenyl)-Thiophosphate) in Different Formulations

The acute, oral toxicity of fenthion (O,O-dimethyl-O-(3-methyl-4-methylmercapto-phenyl)thiophosphate) in different formulations emulgated in water was studied. For male, white rats the approximate values for LD50 found varied from 340 to 560 mg per kg, technical fenthion in commercial products being more toxic than the chemically pure compound. Fenthion in the commercial preparation Lebaycid was more toxic for male, white mice (LD50 approx. 125 mg per kg) than for rats.