本试验旨在研究不同饲养方式和饲养密度对肉鸡生长性能及肉品质的影响.试验采用3×2双因子试验设计,选用7日龄的Ross 308白羽肉鸡504只,3种饲养方式分别为地面厚垫料平养、笼养和网上平养,2个饲养密度分别为12(正常密度)和16只/m²(高密度),共6个组,每个组6个重复.试验期35 d.试验结果显示:1)饲养方式极显著影响7~28日龄和29~42日龄的平均日采食量、平均日增重及料重比(P<0.001).7~28日龄,肉鸡平均日采食量为垫料平养>笼养>网上平养,平均日增重为垫料平养>网上平养>笼养,料重比为网上平养<垫料平养<笼养.29~42日龄,肉鸡平均日采食量垫料平养显著高于笼养和网上平养(P<0.05),平均日增重笼养显著高于垫料平养和网上平养(P<0.05),料重比笼养<网上平养<垫料平养.在7~28日龄,高饲养密度有降低平均日采食量的趋势(0.05<P<0.10),极显著降低28日龄平均体重(P<0.01),但对料重比没有显著影响(P>0.05).在29~42日龄,高饲养密度则有提高平均日采食量的趋势(0.05<P<0.10),极显著降低42日龄平均体重(P<0.01),极显著增加料重比(P<0.01).2)笼养较垫料平养和网上平养组能显著降低肉鸡胸肌率(P<0.05),高饲养密度显著提高了肉鸡腹脂率(P<0.05).3)笼养极显著降低屠宰后45 min胸肌pH(pH₁)(P<0.01),高饲养密度显著降低胸肌pH₁(P<0.01),显著提高胸肉的滴水损失率(P<0.05).4)垫料平养的腿肌中亮度(L^*)、黄度(b^*)最高,且有降低红度(a^*)的趋势;笼养则相反,有降低L^*和b^*,升高a^*的趋势;高饲养密度极显著降低腿肌pH₁(P<0.01),显著提高腿肌中粗脂肪(EE)的含量(P<0.05);饲养方式和饲养密度的交互作用极显著影响腿肌pH₁(P<0.01),在垫料平养和网上平养中提高饲养密度显著降低屠宰后45 min腿肌pH₁(P<0.05),而在笼养组中没有显著差异(P>0.05),且垫料平养的高饲养密度肉鸡的腿肌pH₁最低.综上所述,饲养方式和饲养密度都会影响肉鸡生长性能,但两者不存在交互作用;但在垫料平养和网上平养方式中提高饲养密度会对腿肌肉品质有显著影响.

The effects of rearing system and stocking density on growth performance and carcass composition of broilers were investigated in this experiment. Using a 3×2 factors completely randomized design, a total of 504 seven-day-old male broilers (Ross 308) were divided into 6 groups with 6 replicates per group, respectively. Three rearing systems were designed as battery rearing, floor rearing and net rearing. Two stocking densities were designed as normal density (12 birds/m²) and high density (16 birds/m²). This test lasted for 35 d. The results showed as follows: 1) Rearing system had significant effect on average daily feed intake (ADFI), average daily gain (ADG) and feed to gain ratio (F/G) of broilers aged from 7 to 28 and 29 to 42 days (P<0.001). At 7 to 28 days of age, ADFI of broilers appeared as floor rearing>battery rearing> net rearing, ADG appeared as floor rearing> net rearing> battery rearing, F/G appeared as net rearing< floor rearing< battery rearing. At 29 to 42 days of age, floor rearing significantly enhanced ADFI of broilers compared with battery rearing and net rearing (P<0.05). Battery rearing significantly enhanced ADG of broilers compared with floor rearing and net rearing (P<0.05). F/G appeared as battery rearing> net rearing> floor rearing. High stocking density had the trend to decrease ADFI of broilers aged 7 to 28 days (0.05<P<0.10), significantly decreased BW of broilers aged 28 days (P<0.01), but did not significantly affect F/G (P>0.05). At 29 to 42 days of age, high stocking density had the trend to increase ADFI of broilers (0.05<P<0.10), significantly decreased BW and increased F/G of 42days broilers (P<0.01). 2) Battery rearing significantly decreased breast yields compared with the other two feeding system (P<0.05), high stocking density significantly increased abdominal fat yields (P<0.05). 3) The pH₁ of breast muscle at 45 min after slaughter was significantly decreased in battery rearing (P<0.01). High stocking density significantly decreased pH₁ and increased water-loss rate of breast muscle (P<0.05). 4) Floor rearing had the highest luminance (L^*) and yellowness (b^*), and had the trend to decrease redness (a^*) of leg muscle, whereas, battery rearing group appeared the contrary effect, had the trend to decrease L^* and b^*, and increase a^*. High stocking density significantly decreased pH₁ (P<0.01) and significantly increased the ether extract content of leg muscle (P<0.05). Significant interactive effects between rearing system and stocking density were appeared in pH₁ of leg muscle (P<0.01), high stocking density significantly decreased pH1 of leg muscle of broilers in floor rearing and net rearing system (P<0.05) but not in battery rearing system (P>0.05), and the lowest pH₁ of leg muscle was appeared in floor rearing with high stocking density group. In conclusion, rearing system and stocking density have affect on the growth performance of broilers with no interaction is found. The interaction is found in meat quality of leg muscle, and high stocking density in floor and net rearing system can significant affect the leg muscle quality.