Premating stress alters the vaginal microbiota of gilts

• Autor(a) principal: Alves, Luana
• Data de Publicação: 2019
• Tipo de documento: Dissertação
• Idioma: eng
• Título da fonte: Biblioteca Digital de Teses e Dissertações da USP
• Texto Completo: http://www.teses.usp.br/teses/disponiveis/10/10134/tde-27082019-121926/
• topic: Bem-estar; Cortisol; Cortisol; Housing systems; Lipopolissacarídeo (LPS); Lipopolysaccharide (LPS); Sistemas de alojamento; Welfare

Pre-mating period is often associated with intense stress for sows in commercial production systems, due to the change of management, diet, facilities, among others. Sows are kept in crates during the pre-mating period, which challenge their welfare, occurring the release of cortisol, altering their physiology, modifying responses to pain, infection, injury and stress response. A prolonged exposure to stress can suppress the immune system and increase the susceptibility to infections, often caused by Gram-negative bacteria than contains lipopolysaccharide (LPS) in their cell wall. The role of microbiota in the gut-brain axis is recognized in processes related to stress, obesity, psychiatric disorders, among others, being influenced by environmental, physiological, genotypic and social factors. The hypothesis of this study is that the vaginal microbiota is altered by the stress that female undergoes during the pre-mating period and this alteration compromises their health and welfare. In this study, we investigated the consequences of housing 42 gilts in crates (n=14), indoor group housing (n=14) and outdoors (n=14), three different housing systems, prior to mating. Half of the gilts were challenged with an inoculation of lipopolysaccharides (LPS), in the day of the estrus, simulating an inflammatory condition. Measures of salivary cortisol, behavior, vaginal microbiota, temperature and post-mortem samples were collected. Our data indicates that housing can modulate behavior and physiology, influencing how animals cope with an LPS challenge, which induces a rise in temperature, thus interfering in their welfare. We propose that indoor group housing system, being a barren and poor environment, due the physical and social environment, was more favored to the appearance of pathogens in the swab samples. Greater bacterial diversity was observed in animals housed outdoors when compared with animals housed in crates, corroborating our initial hypothesis, along with a higher prevalence of Enterobacter and Klebsiella in animals housed in crates when compared to outdoor housed animals. Salivary cortisol results suggested that LPSs challenge did not compromised animals hypothalamic-pituitary-adrenal axis (HPA), maybe due the estrus period. We demonstrated that LPS is effective inducing an increase in body temperature, corroborating previous studies, modifying animals behavior. We demonstrated that environmental complexity, as experienced by animals housed outdoor, could indicate better welfare than indoor, barren group housing system and crates. We showed that the housing system influences animals level of activity, with crated animals being less active and performing more biologically irrelevant tasks. Our data showed that keeping gilts in crates compromises their welfare.