中文摘要：

用160羽1日龄健康AA肉鸡进行试验,研究福美双对肉鸡生长性能和胫骨软骨发育不良组织病理学变化的影响。将试验肉鸡预饲1周后随机分为2组。对照组饲以基础日粮;试验组饲以基础日粮添加福美双100mg/kg饲料,4 d后继续饲以基础日粮。试验期23 d。在试验的第4、9、16、23天,计算平均日增重（ADG）和料重比（F/G）;胫骨软骨发育不良（TD）评分,计算TD发病率,观察病理变化;并进行发病不同阶段组织病理学观察。结果表明,第4天试验组肉鸡TD发病率达到94.44%,料重比增加;第4和第9天肉鸡体增重显著下降,病理剖检症状典型。不同阶段组织病理学观察表明,福美双可促进软骨细胞极剧增殖,引起细胞大量死亡,挤压血管以致血管坏死,基质合成受阻,延缓软骨钙化,最终导致前肥大细胞大量聚集形成软骨栓。因此,对肉鸡短期饲喂福美双100mg/kg可显著影响AA肉鸡生长性能,提高TD发病率,引起与自然发生TD相同的形态学和组织病理学变化,是一个较为理想的研究TD发生发展、筛选各种微营养素预防TD的试验动物模型。

英文摘要：

The experiment was conducted to research the effect of thiram on growth performance and histopathologic changes of tibial dyschondroplasia in broilers. 160 one-day-old AA broilers were randomly allotted into two treatments after raised seven days, they were given a regular diet （control group）, or the same diet containing thiram 100 mg/kg for 96 h, then control and experimental group broilers were given the same regular diet. The feeding experiment was ended at 23rd days. ADG, F/G, TD score and TD incidence were studied at 4th, 9th, 16th, 23rd day. Pathological and histopathologic changes of growth plate were also observed at different stages. The results showed that TD incidence was 94.44% at 4th day. Body weight was decreased at 4th and 9th day, and feed to gain ratio （F/G） was increased at 4th day. The pathological symptoms were typical but also more severe than those of spontaneous TD. Through every stage observing with microscope, we found that the thiram promoted chondrocyte proliferation, resulted in large numbers of death cells, compressed blood vessels which led to necrosis of blood vessel, hindered extracellular matrix synthesis, deferred endochondral calcification, formed cartilage plug finally because of accumulated prehypertrophic chondrocytes. As a result, it was demonstrated that thiram could decline growth performance and elevate TD incidence significantly, lead to pathological and histopathologic changes in growth plate, which were similar to those of spontaneously occurring TD. So broiler TD induced by thiram is an ideal animal model for studying TD development and selecting effective different micronutrients against TD.