背景:热应激(HS)是全球家禽生产和福利方面最重要的环境压力因素之一。确定创新和有效的解决方案是必要的。这项研究评估了含有bellirica和穿心莲的植物性饲料添加剂(PHY)对行为模式的影响,血液学和生化参数,氧化应激生物标志物,和HSP70,I-FABP2,IL10,TLR4和mTOR基因在慢性HS条件下肉鸡不同器官中的表达。将总共208只一天大的Avian-480肉鸡随机分配到四个处理中(4个重复/处理,52只鸟/处理):热中向控制处理(TN,饲喂基础饮食);热中性处理(TN,饲喂基础日粮+1公斤/吨饲料PHY);热应激处理(HS,饲喂基础日粮);热应激治疗(HS,饲喂基础日粮+1公斤/吨饲料PHY)。
结果:研究结果表明,HS导致摄食减少,觅食,走路,和舒适行为,同时增加饮酒和休息行为,HS也增加了红色,和白细胞(红细胞和白细胞)计数,和嗜红细胞/淋巴细胞(H/L)比(P<0.05);而两者的平均红细胞体积(MCV),平均红细胞血红蛋白(MCH)降低(P<0.05)。此外,HS负面影响脂质,蛋白质,和葡萄糖水平,肝肾功能检查,和氧化生物标志物通过增加丙二醛(MDA)水平和降低谷胱甘肽(GSH)活性(P<0.05)。热应激(HS)引起十二指肠内HSP70、TLR4基因表达上调,以及所有研究组织中I-FABP2,IL10,mTOR的下调,和肝脏TLR4(P<0.05)与TN治疗相比。植物性饲料添加剂(PHY)通过改善肉鸡的行为有效缓解热应激对肉鸡的负面影响,血液学,生物化学,和氧化应激生物标志物,HSP70表达水平显着降低,而所有组织均显示I-FABP2,IL10,TLR4和mTOR(肝脏除外)水平升高(P<0.05)。
结论:含有bellirica和穿心莲的植物性饲料添加剂(PHY)改善了HS诱导的氧化应激,提高了免疫力以及肉仔鸡的肠道健康和福利。
BACKGROUND: Heat stress (HS) is one of the most significant environmental stressors on poultry production and welfare worldwide. Identification of innovative and effective solutions is necessary. This study evaluated the effects of phytogenic feed additives (PHY) containing Terminalia bellirica and Andrographis paniculata on behavioral patterns, hematological and biochemical parameters, Oxidative stress biomarkers, and HSP70, I-FABP2, IL10, TLR4, and mTOR genes expression in different organs of broiler chickens under chronic HS conditions. A total of 208 one-day-old Avian-480 broiler chicks were randomly allocated into four treatments (4 replicate/treatment, 52 birds/treatment): Thermoneutral control treatment (TN, fed basal diet); Thermoneutral treatment (TN, fed basal diet + 1 kg/ton feed PHY); Heat stress treatment (HS, fed basal diet); Heat stress treatment (HS, fed basal diet + 1 kg/ton feed PHY).
RESULTS: The findings of the study indicate that HS led to a decrease in feeding, foraging, walking, and comfort behavior while increasing drinking and resting behavior, also HS increased red, and white blood cells (RBCs and WBCs) counts, and the heterophile/ lymphocyte (H/L) ratio (P < 0.05); while both mean corpuscular volume (MCV), and mean corpuscular hemoglobin (MCH) were decreased (P < 0.05). In addition, HS negatively impacted lipid, protein, and glucose levels, liver and kidney function tests, and oxidative biomarkers by increasing malondialdehyde (MDA) levels and decreasing reduced glutathion (GSH) activity (P < 0.05). Heat stress (HS) caused the upregulation in HSP70, duodenal TLR4 gene expression, and the downregulation of I-FABP2, IL10, mTOR in all investigated tissues, and hepatic TLR4 (P < 0.05) compared with the TN treatment. Phytogenic feed additives (PHY) effectively mitigated heat stress\'s negative impacts on broilers via an improvement of broilers\' behavior, hematological, biochemical, and oxidative stress biomarkers with a marked decrease in HSP70 expression levels while all tissues showed increased I-FABP2, IL10, TLR4, and mTOR (except liver) levels (P < 0.05).
CONCLUSIONS: Phytogenic feed additives (PHY) containing Terminalia bellirica and Andrographis paniculata have ameliorated the HS-induced oxidative stress and improved the immunity as well as the gut health and welfare of broiler chickens.