Al-Zghoul Mohammad Borhan, Hundam Seif, Mayyas Mohammad, Gerrard David E, Dalloul Rami A
Department of Basic Medical Veterinary Sciences, Faculty of Veterinary Medicine, Jordan University of Science and Technology, Irbid 22110, Jordan.
Department of Animal Production, Faculty of Agriculture, Jordan University of Science and Technology, Irbid 22110, Jordan.
Animals (Basel). 2025 Jun 12;15(12):1736. doi: 10.3390/ani15121736.
Thermal manipulation (TM) during embryogenesis is a promising non-pharmacological strategy to enhance physiological resilience in broiler chickens. This study evaluated the impact of thermal conditioning of fertile eggs on growth performance, inflammatory responses, and molecular stress markers following a post-hatch lipopolysaccharide (LPS) challenge. Fertilized eggs (average weight 62 ± 3 g) were obtained from 35-week-old Indian River broiler breeder hens. A total of 720 eggs were randomly assigned to either the control group ( = 360) or the TM group ( = 360), with each group consisting of two replicates of 180 eggs. Control eggs were maintained under standard incubation conditions (37.8 °C, 56% RH), while TM eggs were subjected to elevated temperature (38.8 °C, 65% RH) for 18 h daily from embryonic day 10 to 18. On post-hatch day 15, control and TM groups were administered either saline or LPS via intraperitoneal (IP) injection. Body weight and temperature, internal organ weights, and splenic mRNA expression levels of inflammatory cytokines, toll-like receptors, transcription factors, and heat shock proteins were assessed. TM did not alter hatchability ( = 0.633), but significantly shortened hatch time ( < 0.05) and improved feed efficiency ( < 0.05). While LPS induced marked inflammatory responses in all birds, those subjected to TM exhibited attenuated proinflammatory cytokine expression, enhanced anti-inflammatory signaling, and differential regulation of stress-associated genes, including nuclear factor kappa B (NF-κB), heat shock protein 70 (HSP70), and heat shock factors (HSFs). These findings suggest that TM during incubation promotes a more regulated immune response and improved stress adaptation post-hatch. This approach offers a potential antibiotic-free intervention to enhance broiler health, performance, and resilience under immunological stress.
胚胎发育期间的热调节（TM）是一种很有前景的非药物策略，可增强肉鸡的生理恢复力。本研究评估了种蛋热调节对孵化后脂多糖（LPS）攻击后的生长性能、炎症反应和分子应激标志物的影响。从35周龄的印度河肉种母鸡获取受精蛋（平均重量62±3克）。总共720枚蛋被随机分配到对照组（n = 360）或TM组（n = 360），每组由180枚蛋的两个重复组成。对照蛋在标准孵化条件（37.8℃，56%相对湿度）下保存，而TM组蛋从胚胎第10天到18天每天在高温（38.8℃，65%相对湿度）下处理18小时。在孵化后第15天，对照组和TM组通过腹腔注射给予生理盐水或LPS。评估体重和体温、内脏器官重量以及脾脏中炎症细胞因子、Toll样受体、转录因子和热休克蛋白的mRNA表达水平。TM未改变孵化率（P = 0.633），但显著缩短了孵化时间（P < 0.05）并提高了饲料效率（P < 0.05）。虽然LPS在所有鸡中诱导了明显的炎症反应，但接受TM处理的鸡表现出促炎细胞因子表达减弱、抗炎信号增强以及应激相关基因的差异调节，包括核因子κB（NF-κB）、热休克蛋白70（HSP70）和热休克因子（HSFs）。这些发现表明，孵化期间的TM促进了更受调节的免疫反应，并改善了孵化后的应激适应。这种方法提供了一种潜在的无抗生素干预措施，以增强肉鸡在免疫应激下的健康、性能和恢复力。
