The role of material stereotypic behaviour on developmental outcomes in piglets

• Ano de defesa: 2018
• Autor(a) principal: Tatemoto, Patricia
• Tipo de documento: Tese
• Tipo de acesso: Acesso aberto
• Idioma: eng
• Instituição de defesa: Biblioteca Digitais de Teses e Dissertações da USP
• Palavras-chave em Português: Bem-estar; Comportamento estereotipado; Emocionalidade; Emotionality; Epigenética; Epigenetics; Pré-natal; Prenatal; Stereotypic behaviour; Welfare
• Link de acesso: http://www.teses.usp.br/teses/disponiveis/10/10134/tde-30042019-110553/

Stereotypic behaviour is considered an indicator of compromised welfare. We have conducted studies to test the controversial hypothesis that stereotypic behaviour helps animals to cope with challenges. We proposed that animals that do not express stereotypies could be under more compromised welfare, than the ones showing the behaviour, when exposed to difficult situations. Rather than asking to the animal if stereotypies are indicating good welfare, we assessed the effects on foetal programming. This study investigated the outcomes of stereotypies measured in sows (Sus scrofa) during gestation in shaping their offsprings phenotype measuring both behavioural and physiological indicators of welfare. Environmental enrichment is an efficient protocol, acting in the causal factors of stereotypies, such as motivational systems, to reduce repetitive, invariant behavioural patterns, defined as stereotypies. We demonstrated that stereotypies in pregnant sows are related with a reduction in fear indicators in their offspring. Then, we showed that environmental enrichment, in the last third of gestation, improved the welfare of sows and also the welfare in their offspring. Comparing the brain of the offspring of sows kept in enriched and non-enriched environments and comparing non-enriched sows performing stereotypies with non-enriched sows not showing stereotypies, we identified eight genes related with neuroplasticity and psychiatric diseases, which were differentially methylated. The main contribution of this study is that maternal stereotypic behaviour during gestation decreases fear indicators and alters the neuroepigenome of the limbic system of the offspring. As far as we know, this is the first evidence showing that stereotypies expressed by the mother during gestation did affect offsprings emotionality, in which the mechanism were epigenetic changes in the brain.