Abdel-Latif Mervat A, El-Far Ali H, Elbestawy Ahmed R, Ghanem Rania, Mousa Shaker A, Abd El-Hamid Hatem S
Department of Nutrition and Veterinary Clinical Nutrition, Faculty of Veterinary Medicine, Damanhour University, Damanhour, AlBeheira, Egypt.
Department of Biochemistry, Faculty of Veterinary Medicine, Damanhour University, Damanhour, AlBeheira, Egypt.
PLoS One. 2017 Oct 23;12(10):e0185153. doi: 10.1371/journal.pone.0185153. eCollection 2017.
Supplementation of exogenous enzymes in chickens has been widely practiced, yet mechanisms responsible are not fully delineated. To investigate the effects of the dietary lysozyme on the growth performance and immunity of broiler chickens, a total of 120 one-day-old Ross 308 chicks were randomly allocated into four groups, each having three replicates (30 birds/group). The chicks were fed the starter (1-21 d) and grower (22-35 d) diets supplemented with 0 (control), 70 (LYZ70), 90 (LYZ90) and 120 (LYZ120) g of lysozyme 10%® per ton of basal diet for five weeks. The results revealed significant improvement in the growth performance and gut environment. There were significant decreases (P < 0.05 or 0.01) in the harmful fecal Coliform and Clostridia and an increase (P ˂ 0.05) in the beneficial Lactobacillus in the lysozyme-supplemented groups, especially in LYZ90. Moreover, the mRNA expressions of Cu, Zn-superoxide dismutase (SOD1), glutathione peroxidase (GSH-Px), interferon-gamma (IFN-γ), interleukin-10 (IL-10), and interleukin-18 (IL-18) were upregulated in response to lysozyme supplementation. In comparison to control, LYZ90 fed birds had a significant increase (P < 0.01) in the GSH-Px gene expression that enhances the antioxidant status of the gut. Expression of the biomarkers involved in the gut non-specific immunity indicated significant increases in the mRNA expression of INF-γ (P < 0.001), IL-10 (P < 0.001), and IL-18 (P < 0.05) in LYZ90 group. Also, serum globulin levels were significantly elevated (P ˂ 0.05) in lysozyme-supplemented groups. Histologically, the intestinal villi length and crypts depth were also enhanced (P ˂ 0.05) by dietary lysozyme supplementation. In conclusion, supplementation of broiler chickens with exogenous lysozyme, especially at 90 g of lysozyme per ton of basal diet dose rate, improved the growth performance, gut antioxidant status, and nonspecific immunity of broiler chickens.
在鸡饲料中添加外源酶已被广泛应用，但其作用机制尚未完全阐明。为了研究日粮溶菌酶对肉鸡生长性能和免疫力的影响，将120只1日龄的罗斯308雏鸡随机分为四组，每组三个重复（每组30只鸡）。雏鸡在1 - 21日龄饲喂开食料，22 - 35日龄饲喂生长料，基础日粮每吨分别添加0（对照组）、70（LYZ70）、90（LYZ90）和120（LYZ120）克10%的溶菌酶®，持续五周。结果显示，生长性能和肠道环境有显著改善。在添加溶菌酶的组中，有害粪便大肠菌群和梭菌显著减少（P < 0.05或0.01），有益乳酸菌增加（P < 0.05），尤其是LYZ90组。此外，添加溶菌酶后，铜锌超氧化物歧化酶（SOD1）、谷胱甘肽过氧化物酶（GSH - Px）、干扰素 - γ（IFN - γ）、白细胞介素 - 10（IL - 10）和白细胞介素 - 18（IL - 18）的mRNA表达上调。与对照组相比，饲喂LYZ90的鸡GSH - Px基因表达显著增加（P < 0.01），增强了肠道的抗氧化状态。参与肠道非特异性免疫的生物标志物表达表明，LYZ90组中INF - γ（P < 0.001）、IL - 10（P < 0.001）和IL - 18（P < 0.05）的mRNA表达显著增加。此外，添加溶菌酶的组血清球蛋白水平显著升高（P < 0.05）。组织学上，日粮添加溶菌酶也使肠绒毛长度和隐窝深度增加（P < 0.05）。总之，给肉鸡补充外源溶菌酶，尤其是每吨基础日粮添加90克溶菌酶的剂量率，可提高肉鸡的生长性能、肠道抗氧化状态和非特异性免疫力。
