Froebel Laney E, Calik Ali, Emami Nima K, Blue Candice E C, Dalloul Rami A
Avian Immunobiology Laboratory, Department of Poultry Science, University of Georgia, Athens, GA 30602, USA.
Avian Immunobiology Laboratory, Department of Poultry Science, University of Georgia, Athens, GA 30602, USA; Department of Animal Nutrition & Nutritional Diseases, Faculty of Veterinary Medicine, Ankara University, Ankara, 06110, Türkiye.
Poult Sci. 2024 Dec;103(12):104339. doi: 10.1016/j.psj.2024.104339. Epub 2024 Sep 18.
In this comparative study, the differential responses of heritage (ACRB; Athens Canadian Random Bred) and modern (Cobb) broilers to a necrotic enteritis (NE) challenge were evaluated. The design was a 2×2 factorial with breed (ACRB and Cobb) and challenge (non-challenged and NE-challenged) as main factors. On day (d) of hatch, 96 male chicks (48 ACRB and 48 Cobb) were allocated to 4 experimental groups with 8 replicate cages and 3 birds/cage. On d 14, birds in the NE-challenged groups were orally gavaged with 3,000 Eimeria maxima sporulated oocysts followed by 2 doses of ∼1×10 CFU of Clostridium perfringens on d 19 and 20. On d 21, 2 birds/cage were necropsied to score NE lesions, and spleen and cecal tonsils (CT) samples were collected from 1 bird/cage for assessing mRNA abundance. Challenged ACRB birds exhibited reduced growth performance and relative growth performance compared to challenged Cobb birds. There was no significant interaction between breed and challenge during the challenge period (d 14-21) for mortality. However, there was a challenge main effect (P ≤ 0.05) on mortality as manifested by greater NE-associated mortality compared to non-challenged birds. No significant breed × challenge interaction or breed main effect on lesion scores were observed in the duodenum, jejunum, and ileum. NE-challenged Cobb birds exhibited greater mRNA abundance of IL-18, TNFα, TLR1.2, TLR2.1, CCR5, CCR6, CCL20, and AvBD1 in CT compared to NE challenged ACRB birds. There was a significant breed × challenge interaction effect on mRNA abundance of IL-10, AvBD13, NK-Lysin, and LEAP2 in the spleen. Moreover, a main effect of breed was observed in IL-1β, IL-18, TNFα, TLR2.1, CCR5, CCL20, and NK-Lysin where ACRB birds had higher mRNA abundance than Cobb birds (P ≤ 0.05). The observed differences in performance, pathology, and mRNA abundance between ACRB and Cobb broilers during the NE challenge highlight the distinct immune response profiles of heritage and modern breeds, emphasizing the need for breed-specific nutritional, managerial, and genetic selection programs for modulating immune responses during enteric disease challenges.
在这项比较研究中，评估了传统品种（ACRB；雅典加拿大随机 bred）和现代品种（科宝）肉鸡对坏死性肠炎（NE）攻毒的不同反应。试验设计为 2×2 析因试验，以品种（ACRB 和科宝）和攻毒（未攻毒和 NE 攻毒）作为主要因素。在孵化日（d），将 96 只雄性雏鸡（48 只 ACRB 和 48 只科宝）分配到 4 个试验组，每组有 8 个重复笼，每个笼 3 只鸡。在第 14 天，NE 攻毒组的鸡口服接种 3000 个巨型艾美耳球虫孢子化卵囊，然后在第 19 天和第 20 天分别口服接种约 1×10 CFU 的产气荚膜梭菌。在第 21 天，每个笼剖检 2 只鸡以评估 NE 病变，并从每个笼的 1 只鸡采集脾脏和盲肠扁桃体（CT）样本以评估 mRNA 丰度。与攻毒的科宝鸡相比，攻毒的 ACRB 鸡生长性能和相对生长性能降低。在攻毒期（第 14 - 21 天），品种和攻毒之间对于死亡率没有显著交互作用。然而，攻毒对死亡率有主要效应（P≤0.05），表现为与未攻毒鸡相比，NE 相关死亡率更高。在十二指肠、空肠和回肠中，未观察到品种×攻毒交互作用或品种对病变评分的主要效应。与 NE 攻毒的 ACRB 鸡相比，NE 攻毒的科宝鸡 CT 中 IL - 18、TNFα、TLR1.2、TLR2.1、CCR5、CCR6、CCL20 和 AvBD1 的 mRNA 丰度更高。在脾脏中，IL - 10、AvBD13、NK - Lysin 和 LEAP2 的 mRNA 丰度存在显著的品种×攻毒交互作用效应。此外，在 IL - 1β、IL - 18、TNFα、TLR2.1、CCR5、CCL20 和 NK - Lysin 方面观察到品种的主要效应，ACRB 鸡的 mRNA 丰度高于科宝鸡（P≤0.05）。在 NE 攻毒期间，ACRB 和科宝肉鸡在性能、病理学和 mRNA 丰度方面观察到的差异突出了传统品种和现代品种不同的免疫反应特征，强调了在肠道疾病攻毒期间需要针对品种的营养、管理和遗传选择方案来调节免疫反应。
