本试验旨在研究相对湿度（RH）和间歇性偏热处理对肉仔鸡免疫功能的影响。试验采用2个偏热水平（26和31℃）和3个RH水平（30%、60%和85%）的2×3因子设计，选取体重相近的22日龄健康爱拔益加（AA）肉仔鸡360只转入环境控制舱，随机分成6个组（Ⅰ、Ⅱ、Ⅲ、Ⅳ、Ⅴ和Ⅵ组），每组6个重复，每个重复10只鸡（公母各占1/2）。预试期7 d，温度21℃，RH 60%。正试期14 d，从29日龄开始，每天10：00-16：00（6 h）将环境控制舱内Ⅰ、Ⅱ和Ⅲ组的温度调至26℃，RH分别调至30%、60%和85%；Ⅳ、Ⅴ和Ⅵ组的温度调至31℃，RH分别调至30%、60%和85%，其余时间环境控制舱内温度与RH均与预试期相同。结果表明：1）Ⅰ和Ⅴ组肉仔鸡的法氏囊指数显著高于Ⅱ和Ⅵ组（P<0.05）；RH为30%和60%时肉仔鸡的法氏囊指数显著高于RH为85%时（P<0.05）。2）试验第7天，Ⅱ组肉仔鸡的血清球蛋白含量显著高于Ⅲ、Ⅳ和Ⅵ组（P<0.05）；26℃时肉仔鸡的血清球蛋白含量显著高于31℃时（P<0.05）。3）试验第1天，Ⅱ组肉仔鸡的血清溶菌酶活性显著高于Ⅲ、Ⅳ和Ⅴ组（P<0.05）；RH为60%时肉仔鸡的血清溶菌酶活性显著高于RH为30%和85%时（P<0.05）。试验第7天，Ⅱ组肉仔鸡的血清溶菌酶活性显著高于Ⅰ、Ⅴ和Ⅵ组（P<0.05）。试验第1和14天，26℃时肉仔鸡的血清溶菌酶活性显著高于31℃时（P<0.05）。4）试验第1和14天，Ⅵ组肉仔鸡的血清白细胞介素-1β（IL-1β）含量显著高于Ⅰ、Ⅱ、Ⅲ和Ⅴ组（P<0.05）；31℃时肉仔鸡血清IL-1β和白细胞介素-6（IL-6）含量均显著高于26℃时（P<0.05）。试验第1、7和14天，Ⅲ、Ⅳ、Ⅴ和Ⅵ组肉仔鸡的血清IL-6含量显著高于Ⅰ和Ⅱ组（P<0.05）；RH为85%时肉仔鸡的血清IL-6含量均显著高于RH为30%和60%时（P<0.05）。总之，RH和间歇性偏热处理以及两者的交互作用不同程度地影响肉仔鸡的免疫功能，其中较高偏热和较高湿度（31℃+85% RH）的影响最大。

This experiment was conducted to investigate the effects of relative humidity (RH) and intermittent partial heat temperatures on immune functions of broilers. According to 2×3 factorial design of two partial heat temperatures (26 and 31℃) and three RH levels (30%, 60% and 85%), three hundred and sixty 22-day-old healthy Arbor Acres (AA) broilers with similar body weight were allotted into environment chambers, and randomly divided into 6 groups (groups Ⅰ, Ⅱ, Ⅲ, Ⅳ, Ⅴ and Ⅵ), each group (chamber) contained six cages with ten birds per cage (male and female in half), and each cage as a replicate. The pre-test period lasted for 7 days and broilers were kept at 21℃ and 60% RH. The trial lasted for 14 days. When broilers were 29-day-old, the temperatures of groups Ⅰ, Ⅱ and Ⅲ were kept at 26℃, regulating the RH to 30%, 60% and 85%, respectively; the temperatures of groups Ⅳ, Ⅴ and Ⅵ were kept at 31℃, while regulating the RH to 30%, 60% and 85%, respectively. And the temperature and RH of groups were kept six hours each day, at 10:00 to 16:00, after the period, broilers were kept at 21℃ and 60% RH. The results showed as follows:1) the index of bursa of broilers in groups Ⅰ and Ⅴ was significantly higher than that in groups Ⅱ and Ⅵ (P<0.05), and the index of bursa at 30% RH and 60% RH was significantly higher than that at 85% RH (P<0.05). 2) On day 7, the content of globulin in serum of broilers in group Ⅱ was significantly higher than that in groups Ⅲ, Ⅳ and Ⅵ (P<0.05), and the content of globulin in serum at 26℃ was significantly higher than that at 31℃ (P<0.05). 3) On day 1, the activity of lysozyme in serum of broilers in group Ⅱ was significantly higher than that in groups Ⅲ, Ⅳ and Ⅴ (P<0.05), and the activity of lysozyme in serum at 60% RH was significantly higher than that at 30% RH and 85% RH (P<0.05). On day 7, the activity of lysozyme in serum in group Ⅱ was significantly higher than that in groups Ⅰ, Ⅴ and Ⅵ (P<0.05). On days 1 and 14, the activity of lysozyme in serum at 26℃ was significantly higher than that at 31℃ (P<0.05). 4) On days 1 and 14, the content of interleukin-1β (IL-1β) in serum of broilers in group Ⅵ was significantly higher than that in groups Ⅰ, Ⅱ, Ⅲ and Ⅴ (P<0.05), and the contents of IL-1β and interleukin-6 (IL-6) in serum at 31℃ were significantly higher than those at 26℃ (P<0.05). On days 1, 7 and 14, the content of IL-6 in serum in groups Ⅲ, Ⅳ, Ⅴ and Ⅵ was significantly higher than that in groups Ⅰ and Ⅱ (P<0.05), and the content of IL-6 in serum at 85% RH was significantly higher than that at 30% RH and 60% RH (P<0.05). In conclusion, RH, intermittent partial heat temperatures and their interaction affect the immune function of broilers to varying extent, and the higher temperature and humidity (31℃+85% RH) have the most impact.