ABSTRACT The experiment was conducted to evaluate the effects of different levels of cottonseed meal (CSM) in laying hens. A total of 175 hens, 60-wk-old, were allocated to five treatments. The control group was fed a corn-soybean meal diet, and the four experimental diets contained 19.5, 67.5, 115.5, and 163.5 g/kg CSM, in which free gossypol level was 20, 70, 120, 170 mg/kg, respectively. The results showed that no significant differences were observed on laying performance, egg production and organ indexes among all groups. Jejunum and ileum mucosa slgA were significantly lower than the control group when FG reached 120 mg/kg (P < 0.05). The ileum IL-2 was significantly decreased when FG reached 70 mg/kg (P < 0.05). The ileum TNF-α was increased linearly and the liver damage was aggravated with the increase of FG. In conclusion, FG can destroy intestinal immunity and liver tissue and dietary FG in laying hens should be limited within 70 mg/kg.

中文翻译：

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不同水平棉籽粕对蛋鸡产蛋性能、蛋品质、肠道免疫和肝脏组织病理学的影响

摘要 本试验旨在评估不同水平的棉籽粕 (CSM) 对蛋鸡的影响。总共 175 只 60 周龄的母鸡被分配到五个处理组。对照组饲喂玉米-豆粕日粮，四种试验日粮的CSM含量分别为19.5、67.5、115.5和163.5 g/kg，其中游离棉酚水平分别为20、70、120、170 mg/kg。结果表明，各组间产蛋性能、产蛋量和器官指标均无显着差异。当FG达到120 mg/kg时，空肠和回肠黏膜slgA显着低于对照组（P < 0.05）。当 FG 达到 70 mg/kg 时，回肠 IL-2 显着降低（P < 0.05）。回肠TNF-α呈线性升高，肝损害随着FG的增加而加重。综上所述，