马杜拉霉素对肉鸡的临床毒性及病理组织学研究

本试验观察了饲料中添加不同浓度(10、17.5、25mg/kg)马杜拉霉素对科宝肉鸡的毒性。结果表明:17.5、25mg/kg可引起肉鸡明显的临床症状,如采食减少、站立困难、消瘦等,并继发腹水症。10mg/kg马杜拉霉素可引起鸡慢性中毒,因此,临床使用应低于这个浓度,用药时间不宜过长。病理形态学检验表明,中毒鸡的心/体比、肝/体比、肾/体比升高,脾/体比、法氏囊/体比降低;病理组织学检验表明,心肌和骨骼肌以肌肉变质性炎、肝脏以变质性炎、法氏囊和脾脏以淋巴细胞减少为特征。说明马杜拉霉素对心、肝、肾、脾、法氏囊等器官有损伤。     

马杜拉霉素对肉鸡的临床毒性及病理组织学研究

本试验观察了饲料中添加不同浓度（10、17.5、25mg/kg）马杜拉霉素对科宝肉鸡的毒性。结果表明：17.5、25mg/kg可引起肉鸡明显的临床症状，如采食减少、站立困难、消瘦等，并继发腹水症。10mg/kg马杜拉霉素可引起鸡慢性中毒，因此，临床使用应低于这个浓度，用药时间不宜过长。病理形态学检验表明，中毒鸡的心/体比、肝/体比、肾/体比升高，脾/体比、法氏囊/体比降低；病理组织学检验表明，心肌和骨骼肌以肌肉变质性炎、肝脏以变质性炎、法氏囊和脾脏以淋巴细胞减少为特征。说明马杜拉霉素对心、肝、肾、脾、法氏囊等器官有损伤。     

马杜霉素对肉鸡的临床毒性研究

本试验观察了不同浓度马杜霉素饮水剂及马杜霉素助溶剂饮水对艾维茵肉鸡的心,肝,肺,肾及胸肌的毒性。结果表明;１６ｍｇ／Ｌ马杜霉素组中毒的神经症状明显,并有致死性;对心脏有损伤的为１２,１６ｍｇ／Ｌ马杜霉素组;对肝脏有损伤的８μｌ／Ｌ助溶剂组和８,１２,１６ｍｇ／Ｌ马杜霉素组;对肾脏有损伤的为１６ｍｇ／Ｌ马杜霉素组;影响胸肌生长的有１２,１６ｍｇ／Ｌ马杜霉素组;同时分析得出;马杜霉素饮水剂量应小于８ｍ     

马杜拉霉素对兔的短期毒性试验

为评价马杜拉霉素的安全性，对兔进行了短期毒性测试。结果：染毒兔在12－24h后出现腹泻、多尿、体重骤减、伏臣、嗜睡和四肢瘫软无力等症状。剖检见兔体极度消瘦，有的兔体腔积液，偶见纤维素沉着；心肌松软失去弹性，呈煮肉样外观；肺、肝、肾、脾肿胀，重量增加，均有不同程度的瘀血、出血、变性；各脏器系数及含水量有不同程度的改变；胃肠黏膜出血、变性、坏死、脱落。马杜拉霉素的毒性上限指标：LD0为0．39mg/kg体重，MLD为0．47mg/kg体重，LD50为0．70mg/kg体重，LD100为1．16mg/kg体重。     

马杜拉霉素不宜用于兔

马杜拉霉素是含 1 %马杜拉霉素铵的预混剂 ,为控制鸡球虫病的常用药品。具有用量少、安全、高效等特点。对其它动物均不宜应用。笔者近年来收治兔马杜拉霉素中毒多例 ,现介绍如下。1　发病情况　市郊黄递铺村农户王某 1 998年 7月1 0日从保定市某兔场引进獭兔 1 0 0只 ,其中有 1 /2怀孕待产母兔。兔群均在原场按时接种兔瘟疫苗和巴氏杆菌苗 ;7月 1 2日王某在饲料中拌加马杜拉霉素 ,按包装使用说明 ,每袋 2 50 g应拌料 50 0 kg。而王某在每盆料约 1 .5～ 2 kg加入 1 /1 0袋药物 ,用量明显超过规定剂量。用药后第 2天有部分兔精神沉郁 ,减食 ,…     

水貂犬瘟热病理组织学观察

为了加深对犬瘟热病理学损害的认识,为该病的诊断、治疗以及判定预后提供依据,对确诊为犬瘟热的水貂的主要脏器进行了病理组织学观察。病理学变化特征为心肌细胞间隙明显增宽,有淋巴细胞浸润;肝脏出血、瘀血,淋巴细胞浸润及肝细胞肿胀、坏死;脾脏出血,脾脏白髓体积缩小;肺脏出血,大量淋巴细胞浸润;肾脏淋巴细胞浸润,部分肾小管上皮细胞肿胀、坏死。结果表明:患貂出现了广泛的组织损伤,并伴随机体各器官明显的炎症反应。     

牛心朴子总生物碱对小鼠的毒性试验

近年来 ,由于旱、风沙、鼠害、盐碱等自然条件的影响 ,以及草场管理不善 ,如载畜过重 ,过度采挖 ,过度放牧等 ,造成草场沙化、退化。使优良牧草大量减少 ,而有毒有害植物大量繁衍。毒草不仅与优良牧草竞争生存 ,降低优良牧草的产量 ,而且和优良牧草竞争养分、水分和阳光 ,以致使优良牧草逐年衰退 ,而毒草则愈加旺盛。据陈善科等 (1992 )报道 ,阿拉善盟荒漠草场牛心朴子又称老瓜头 ,属于萝摩纲萝摩科鹅绒藤属植物 Cynanchum komanovii,分布面积达 98万hm2 ,占可利用草场面积的 10 %。牛心朴子已成为内蒙与西部草场最具代表性植物 ,牛心朴子…     

“花肝病”雏番鸡病理组织学变化

1998年下半年以来，在佛山、南海、三水、肇庆、东莞等广大地区饲养的雏番鸭群，暴发一种高发病率、高致死率的急性烈性传染病。该病主要发生于 6～ 20日龄的雏番鸭群，死亡率可高达 90％以上，甚至全群死亡。发病雏鸭症状表现为迅速脱水消瘦、衰竭死亡。病理变化特征是心脏、胰脏、脾脏、肾脏等多个内脏器官，尤其是肝脏表面和实质广泛形成灰白色粟粒大小的坏死点 (俗称“花肝病” )。本病的病原，目前尚未完全确定。为引起同行对本病的注意，进一步做好诊断与防制工作，现就该病的剖检变化及 5例具有典型病变的病理组织学观察报告如下。 1…     

阿奇霉素对麻花肉鸡的亚急性毒性研究

将80只19日龄麻花肉鸡随机分为4组，每组2个重复，分别以0、50、100、200mg／I。阿奇霉素水溶液供试验鸡连续自由饮用14d，观察其亚急性毒性作用。结果显示，低剂量组（50mg／L）鸡的生长速度、饲料转化率显著强于其他组（P〈0．05）；高剂量组（200mg／L）鸡血清丙氨酸氨基转移酶活性和肝脏器系数与对照组（0mg／L）和低剂量组存在极显著差异（P〈0．01），肝肿大变黄，质脆，出现坏死灶，胆囊肿大，胆汁充盈，肝细胞排列无序、胞浆空泡化、弥漫性脂肪变性。表明，低剂量阿奇霉素能促进鸡生长，大于100mg／L则对肝、胆产生毒性作用。     

马杜霉素对肉仔鸡免疫器官发育影响的研究

为了探讨马杜霉素对肉仔鸡免疫器官的影响,试验选择体重相近的1日龄肉仔鸡200只,在日粮中分别不添加马杜霉素(Ⅰ组)和添加5.0 mg/kg(Ⅱ组)、7.5 mg/kg(Ⅲ组)、10.0 mg/kg(Ⅳ组)的马杜霉素,连续饲喂4周,测定各组雏鸡胸腺、脾脏、法氏囊指数。结果表明:5.0 mg/kg马杜霉素3周对肉仔鸡免疫器官发育有一定促进作用,但3周后呈现一定的抑制作用;用7.5 mg/kg和10.0 mg/kg马杜霉素饲喂1周即可抑制免疫器官的生长发育,其抑制作用能持续至停药后1周,但在停药3周后基本恢复正常。说明马杜霉素对肉仔鸡免疫器官发育的抑制作用呈现一定的量效和时效效应。     

Efficacy of maduramicin against ionophore-tolerant field isolates of coccidia in broilers

Maduramicin ammonium was given at 2.5-8 ppm in the feed to broilers experimentally infected with coccidia recently isolated from broiler farms where ionophores had been used for several years. Infection pressure varied from mild to severe in five trials: mortality in unmedicated controls ranged from 0 to 59%, intestinal lesion scores were high, and weight gain was depressed by the infections. The cultures of Eimeria were partly resistant to ionophores: birds medicated with monensin at 100-121 ppm had only modest reductions in lesion scores and incomplete protection against weight loss or mortality. Control of infections by maduramicin was significant at 4 ppm but best at 5-7 ppm. Maduramicin was more effective than monensin or narasin, but about the same as salinomycin, in reducing lesions and mortality and in protecting performance. Maduramicin was well tolerated within the dose range of 5-7 ppm.     

Clinico-haematological and mineral studies on experimental maduramicin toxicity in chickens

Clinico-haematological and mineral studies were carried out in experimental chickens given maduramicin medicated feed at 5 and 10 ppm for 21 days. Maduramicin medication in both medicated groups caused growth retardation. Clinical signs namely watery diarrhoea, depression, dullness and ruffled feathers were noticed in chickens from second week of the medication at 10 ppm but this effect was seen from third week in the birds given maduramicin at 5 ppm. Maduramicin medication caused significant reduction in haemoglobin in both the medicated group from day 14 and total erythrocyte count and packed cell volume in 10 ppm group on day 21. There was an increase in MCV in 10 ppm group on day 21 indicating macrocytic anaemia and decrease in mean corpuscular haemoglobin concentration (MCHC) in both the medicated groups indicating hypochromic anaemia. The leucopenia due to lymphopenia was observed in 10 ppm group on day 21. Maduramicin medication caused significant increase in serum Zn in 10 ppm group and decrease in Cu concentration in both the medicated groups from day 14. It is concluded that maduramicin caused toxic effects from day 14 in both the medicated groups.     

喹赛多对肉鸡的急性毒性试验

喹恶啉类是临床应用广泛的一类抗菌促生长饲料添加剂，喹乙醇与卡巴氧是本类应用最广泛的主要产品，但因对动物具有不同程度的毒副作用而被禁用或被严格限制使用。喹赛多是喹恶啉类新品种，由华中农业大学兽药研究所合成，本品抗菌效果与喹乙醇相似，对家禽、家畜及水产动物均有良好的抗病促生长效果，对实验动物的毒副作用均比同类产品低心。     

Nonprotein nitrogen-induced ammonia toxicosis and ammoniated feed toxicity syndrome

In spite of all the reports and work done, the ammoniated feed toxicity syndrome still is quite a mystery. Given its enigmatic cause, prevention is our only current means of control. The data that is recorded from each new episode, however, may help to piece together the exact mechanism so that one day it can be understood and treated.     

犬附红细胞体病的组织病理学观察

附红细胞体病是由附红细胞体感染所致的一种人畜共患病。本病广泛分布于世界各地，其宿主特异性较强，其中猪的发病率和致死率最高。犬的附红细胞体病主要以高热、渐进性消瘦为特征，感染率可达80％以上，本病已成为兽医领域研究的热点之一。近年来，对犬附红细胞体病的流行病学、临床表现、检测方法、治疗药物等报道较多，而对剖检变化及组织     

Haematological and histopathological findings in young broilers reared in poorly and well ventilated environments

Two strains of broilers, a modern commercial strain and a strain which has not recently been selected for economic traits, were reared in adjacent rooms which were identical except that one had good ventilation and the other poor ventilation. Mean cell volume (MCV) of erythrocytes was studied in relation to plasma viscosity and the incidence of lung nodules. Poor ventilation was associated with an increased incidence of lung nodules and increased plasma viscosity but there was no correlation between MCV and the number of nodules. Although environmental factors may influence MCV the genotype of the bird appears to be of major importance.