Early-life microbiota transplantation affects behavioural responses, serotonin and immune characteristics in chicken lines divergently selected on feather pecking

Abstract

in life 17. These findings suggest that the gut microbiota influences behavioural and physiological characteristics in poultry and could therefore influence a bird's ability to cope with environmental and social challenges, such as those encountered in animal production systems. Excessive damaging behaviours are indicative of an animal's inability to cope with a restrictive environment and are frequently seen in production animals. Feather pecking (FP) in chickens is one such damaging behaviour, which involves hens pecking and pulling at feathers of conspecifics, thereby reducing animal welfare and productivity 18. Feather pecking is multifactorial and has been linked to numerous behavioural characteristics, such as fearfulness, stress and activity, as well as physiological characteristics, such as serotonergic, dopaminergic and immune systems 19-21. Since behavioural and physiological systems that are related to FP are also affected by the gut microbiota, microbiota might play a role in the development of FP. Indeed, lines selected for high FP (HFP) and low FP (LFP) differ in behavioural responses, stress response, activity, central serotonergic and dopaminergic activity, peripheral serotonin, innate and adaptive immune characteristics 22-28. Moreover, the HFP and LFP lines differ in intestinal microbial metabolites and microbiota composition determined from caecal droppings and intestinal luminal content 29-31. These findings point to a relationship between the gut microbiota and FP, however, it is unknown whether the gut microbiota influences the development of FP. Therefore, this study aims to identify the effects of early-life microbiota transplantation on FP and behavioural and physiological characteristics related to FP in lines divergently selected for FP (HFP and LFP lines). We further identify the effects of microbiota transplantation on microbiota composition. We hypothesize that microbiota transplantation results in recipients adopting a similar behavioural profile as that seen in the donor line. For example, LFP birds receiving HFP microbiota show more FP and more active behavioural responses compared to LFP birds receiving LFP microbiota or control treatment. Results High and low feather pecking transplantation pools had distinct microbiota composition. Gut microbiota was collected from adult chickens of the HFP and LFP lines that were shown to differ in microbiota composition 31. Transplantation pools were made per line and could be distinguished from each other in terms of microbiota composition using a principal component analysis (PCA) (Fig. 1A). The orders of Clostridiales and Lactobacillales had the highest relative abundance in both pools. The HFP pool had a higher relative abundance of

Large-Scale Phenotyping of Livestock Welfare in Commercial Production Systems: A New Frontier in Animal Breeding

“…The authors detected common genomic regions for the presence of bacteria such as Lactobacillus and L. crispatus and traits such as feeding behavior (Mignon-Grasteau et al, 2017). A pilot study investigated the effects of early-life microbiota transplantation on feather pecking, and behavioral and physiological traits related to feather pecking (van der Eijk et al, 2020). The researchers reported that chicken lines with divergent genetic merit for feather pecking had different microbiota composition.…”

A Proposed Role for Pro-Inflammatory Cytokines in Damaging Behavior in Pigs

“…It has been suggested that the increased inflammatory state seen in depressed individuals (humans) is due to a response to LPS in intestinal bacteria that reach the circulation due to increased permeability in the intestinal wall ( 180 , 181 ). Hens with high and low levels of repetitive feather-pecking behavior have differences in intestinal microbial metabolites ( 182 ), but transplantation of gut microbiota from the high to low feather pecker line and vice versa did not have a strong effect on microbiota nor on feather pecking ( 183 ). A recent report showed more lactobacilli in the gut microbiota of pigs that neither bit nor were bitten compared to biters and victims (Rhabi et al, under review).…”

5-Hydroxytryptophan Suppresses the Abdominal Fat Deposit and Is Beneficial to the Intestinal Immune Function in Broilers

“…In broiler, L-tryptophan supplementation could relieve stress-effected expression of IL-1, IL-6, IL-10, and TNF-α by regulating 5-HT metabolism (Yue et al, 2017) and increase serum IgM concentration quadratically in laying hen reared under hot and humid summer conditions (Dong et al, 2012). Except of the behavioral responses, earlylife microbiota transplantation has long-term effects on immune characteristics and peripheral serotonin of chicken in a genotypedependent way (van der Eijk et al, 2020). As the intermediate metabolite of the essential amino acid L-tryptophan in the biosynthesis of 5-HT, 5-Hydroxytryptophan (5-HTP) has been used as a clinically effective serotonin precursor (Birdsall, 1998).…”