PEGASE, INRAE, Agrocampus Ouest, 16 Le Clos Domaine de la Prise, Saint-Gilles35590, France.
GenPhySE, Université de Toulouse, INRA, INPT, INP-ENVT, 24, chemin de Borde-Rouge - Auzeville Tolosane, Castanet Tolosan31320, France.
Animal. 2020 Nov;14(11):2277-2287. doi: 10.1017/S1751731120001299. Epub 2020 Jun 18.
Mycotoxins are a major contaminant of pig feed and have negative effects on health and performance. The present study investigated the impact of single or repeated acute challenges with a diet naturally contaminated with deoxynivalenol (DON) and zearalenone (ZEN) on growth performances of finishing pigs and their fecal microbiota composition. A total of 160 pigs (castrated males and females) in two successive batches were randomly divided into four experimental groups of 40 pigs each. The control group received a control finisher diet from 99 to 154 days of age. Challenged groups were subjected to a 7-day acute challenge by being fed a DON- and ZEN-contaminated diet (3.02 mg DON/kg feed and 0.76 mg ZEN/kg feed) at 113 days (group DC), 134 days (group CD) or both 113 and 134 days (group DD). Microbiota composition was analyzed via 16S rRNA sequencing from fecal samples collected from the 80 females at 99, 119, 140 and 154 days. Challenged pigs (i.e. groups DC, CD and DD) reduced their average daily feed intake by 25% and 27% (P < 0.001) and feed efficiency by 34% and 28% (P < 0.05) during the first and second mycotoxin exposure, respectively. Microbiota composition was affected by mycotoxin exposure (P = 0.07 during the first exposure and P = 0.01 during the second exposure). At the family level, mycotoxin exposure significantly (P < 0.05) decreased the relative abundances of Ruminococcaceae, Streptococcaceae and Veillonellaceae and increased that of Erysipelotrichaceae at both 119 and 140 days of age. After the 7-day DON/ZEN challenge, the relative abundance of 6 to 148 operational taxonomic units (OTUs) differed among the treatment groups. However, none of these OTUs changed in all treatment groups. Using 27 functional pathways, pigs exposed to DON/ZEN challenges could be distinguished from control pigs using sparse partial least squares discriminant analysis, with a 15% misclassification rate. Regarding the functionality of these predictors, two pathways were involved in detoxifying mycotoxins: drug metabolism and xenobiotic metabolism by cytochrome P450. In challenged pigs, microbiota composition returned to the initial state within 3 weeks after the end of a single or repeated DON/ZEN challenge, highlighting the resilience of the gut microbiome. The feeding and growth performances of the pigs during challenge periods were significantly correlated with biological pathways related to health problems and modifications in host metabolism. To conclude, short-term DON/ZEN challenges resulted in transient modifications in the composition and functions of fecal microbiota.
霉菌毒素是猪饲料的主要污染物，对健康和性能有负面影响。本研究调查了单次或重复急性挑战日粮中自然污染的脱氧雪腐镰刀菌烯醇（DON）和玉米赤霉烯酮（ZEN）对育肥猪生长性能及其粪便微生物群落组成的影响。总共 160 头猪（去势公猪和母猪）分为两批连续进行，每批 40 头猪随机分为 4 个实验组。对照组在 99 至 154 日龄时接受对照育肥日粮。113 日龄（DC 组）、134 日龄（CD 组）或 113 日龄和 134 日龄（DD 组）饲喂含有 3.02 mg DON/kg 饲料和 0.76 mg ZEN/kg 饲料的 DON 和 ZEN 污染日粮，进行为期 7 天的急性挑战。从 99、119、140 和 154 日龄的 80 头母猪的粪便样本中通过 16S rRNA 测序分析微生物群落组成。在第一次和第二次霉菌毒素暴露期间，受挑战的猪（即 DC、CD 和 DD 组）的平均日采食量分别减少了 25%和 27%（P < 0.001），饲料效率分别减少了 34%和 28%（P < 0.05）。在第一次暴露期间，微生物群落组成受霉菌毒素暴露的影响（P = 0.07），在第二次暴露期间，微生物群落组成受霉菌毒素暴露的影响（P = 0.01）。在科水平上，霉菌毒素暴露显著（P < 0.05）降低了瘤胃球菌科、链球菌科和韦荣球菌科的相对丰度，并增加了肠杆菌科的相对丰度，在 119 和 140 日龄时均如此。在 7 天 DON/ZEN 挑战后，处理组之间的 6 到 148 个操作分类单元（OTUs）的相对丰度存在差异。然而，在所有处理组中，这些 OTUs 都没有发生变化。使用 27 种功能途径，DON/ZEN 挑战后的猪可以与对照猪区分开来，误分类率为 15%。关于这些预测因子的功能，有两条途径参与了霉菌毒素的解毒：细胞色素 P450 介导的药物代谢和异生物质代谢。在受挑战的猪中，单次或重复 DON/ZEN 挑战结束后 3 周内，微生物群落组成恢复到初始状态，突出了肠道微生物组的弹性。挑战期间猪的采食量和生长性能与与健康问题和宿主代谢变化相关的生物途径显著相关。总之，短期 DON/ZEN 挑战导致粪便微生物群落组成和功能发生短暂变化。
