该研究的目的是评估促肾上腺皮质激素释放因子（CRF）受体信号传导与预防性抗生素施用之间对新断奶和运输猪肠道生理学的相互作用。猪（n = 56；5.70 ± 1.05 kg）断奶（20.49 ± 0.64 天），采集血样，然后腹腔注射生理盐水（SAL；n = 28 头猪）或 CRF 受体拮抗剂（ CRFA；n = 28 头猪；30 μg/kg 体重；Astressin B)，然后用牲畜拖车运输 12 小时 49 分钟。分别在运输过程中的 4 小时 42 分钟和 11 小时 36 分钟进行第二次和第三次腹腔注射。运输后，对 4 头 SAL 和 4 头 CRFA 猪进行了血液采样并实施了安乐死。其余 48 头猪单独饲养并给予膳食抗生素 [AB; n = 12 头 SAL 和 12 头 CRFA 猪；运输后 14 天，使用金霉素 (441 ppm) 泰妙菌素 (38.6 ppm)] 或不使用日粮抗生素（NAB；n = 12 头 SAL 和 12 头 CRFA 猪）。在第 12 小时以及第 3、7 和 14 天收集血液，然后在断奶和运输后第 7 天（n = 24）和第 14 天（n = 24）对猪实施安乐死。与断奶和运输后的 SAL 猪相比，CRFA 猪的循环皮质醇降低 (p = 0.05)。第 7 天，AB 喂养的猪的空肠绒毛高度和隐窝深度总体上比 NAB 喂养的猪更大（p < 0.05）。第 14 天，与 SAL 猪相比，CRFA 猪的回肠隐窝深度减少 (p = 0.02)。与 SAL 猪相比，CRFA 猪的空肠 CRF mRNA 丰度在第 7 天趋于降低 (p = 0.09)。第 14 天，与 NAB 喂养的猪相比，AB 喂养的猪的空肠肿瘤坏死因子-α 降低（p = 0.01）。第 7 天，与饲喂 NAB 日粮的 CRFA 猪相比，饲喂 AB 日粮的 CRFA 猪的葡萄糖短路电流变化趋于增加 (p = 0.07)。总之，CRFA 猪和饲喂 AB 的猪在断奶后和运输后具有一些相似的生物肠道功能指标。版权所有 © 2023 McConn、Kpodo、Rivier、Behan、Richert、Radcliffe、Lay 和 Johnson。

The study objective was to evaluate the interaction between corticotrophin releasing factor (CRF) receptor signaling and prophylactic antibiotic administration on intestinal physiology in newly weaned and transported pigs. Pigs (n = 56; 5.70 ± 1.05 kg) were weaned (20.49 ± 0.64 d), a blood sample was taken, and then pigs were given an intraperitoneal injection of saline (SAL; n = 28 pigs) or a CRF receptor antagonist (CRFA; n = 28 pigs; 30 μg/kg body weight; Astressin B), and then were transported in a livestock trailer for 12 h and 49 min. A second and third intraperitoneal injection was given at 4 h 42 min and 11 h 36 min into the transport process, respectively. Following transport, 4 SAL and 4 CRFA pigs were blood sampled and euthanized. The remaining 48 pigs were individually housed and given dietary antibiotics [AB; n = 12 SAL and 12 CRFA pigs; chlortetracycline (441 ppm) + tiamulin (38.6 ppm)] or no dietary antibiotics (NAB; n = 12 SAL and 12 CRFA pigs) for 14 d post-transport. Blood was collected at 12 h and on d 3, 7, and 14, and then pigs were euthanized on d 7 (n = 24) and d 14 (n = 24) post-weaning and transport. Circulating cortisol was reduced (p = 0.05) in CRFA pigs when compared to SAL pigs post-weaning and transport. On d 7, jejunal villus height and crypt depth was greater overall (p < 0.05) in AB-fed pigs versus NAB-fed pigs. On d 14, ileal crypt depth was reduced (p = 0.02) in CRFA pigs when compared to SAL pigs. Jejunal CRF mRNA abundance tended to be reduced (p = 0.09) on d 7 in CRFA pigs versus SAL pigs. On d 14, jejunal tumor necrosis factor-alpha was reduced (p = 0.01) in AB-fed pigs versus NAB-fed pigs. On d 7, change in glucose short-circuit current tended to be increased (p = 0.07) in CRFA pigs fed the AB diet when compared to CRFA pigs fed the NAB diet. In conclusion, CRFA pigs and pigs fed AB had some similar biological intestinal function measures post-weaning and transport.Copyright © 2023 McConn, Kpodo, Rivier, Behan, Richert, Radcliffe, Lay and Johnson.