Stress significantly affects the health, welfare, and productivity of farm animals. We performed a longitudinal study to evaluate stress’s effects on pig performance, feeding behavior, and fecal microbiota composition. This study involved 64 Duroc pigs during the fattening period, divided into two experimental groups: a stress group (n = 32) and a control group (n = 32). Stressed groups had less space and were mixed twice during the experiment. We monitored body weight, feed efficiency, feeding behavior, and fecal microbiota composition. Compared to the control group, the stressed pigs exhibited reduced body weight, feed efficiency, fewer feeder visits, and longer meal durations. In the fecal microbiota, resilience was observed, with greater differences between groups when sampling was closer to the stressful stimulus. Stressed pigs showed an increase in opportunistic bacteria, such as Streptococcus, Treponema and members of the Erysipelotrichaceae family, while control pigs had more butyrate- and propionate-producing genera like Anaerobutyricum, Coprococcus and HUN007. Our findings confirm that prolonged stress negatively impacts porcine welfare, behavior, and performance, and alters their gut microbiota. Specific microorganisms identified could serve as non-invasive biomarkers for stress, potentially informing both animal welfare and similar gut-brain axis mechanisms relevant to human research.

Pigs are a social species, and they establish hierarchies for better use of resources and to reduce conflicts. However, in pig production, the opportunities for growth can differ between dominant and subordinate animals. In the present study, a system was tested to perform a dominant versus subordinate test in growing pigs to investigate how the hierarchy affects feeding behaviour, growth, and gut microbiota assessed in faeces. Sixty-four animals housed in eight different pens were used, with four castrated males and four females in each one, weighing 18 kg at arrival and maintained during the whole growing period, until 140 kg. Three stool samples were obtained from the animals directly from the anus to avoid contamination of the faeces 58, 100, and 133 days after the start of the study to investigate the microbiota composition. The dominant animals had higher gains during the growing period than the subordinates. In addition, they were performing more visits to the feeder throughout the day. Differential abundance patterns were observed in five bacterial genera, with Oliverpabstia, Peptococcus, and Faecalbacterium being more abundant in dominant animals and Holdemanella and Acetitomaculum being overrepresented in subordinate ones. This microbial biomarker accurately classified dominant versus subordinate groups of samples with an AUC of 0.92.

Pigs are a social species and they stablish hierarchies for a better use of resources and to reduce conflicts. However, in pig production, the opportunities for growing can differ in dominant and subordinate animals. In the present study a system was tested to perform a Dominance versus Subordinate test in growing pigs to investigate how the hierarchy affects feeding behaviour, growth and gut microbiota assessed in faeces. 64 animals housed in eight different pens were used, with four castrated males and four females in each one, weighing 18kg at arrival and maintained during the whole growing period, until 140 kg. Three stool samplings were obtained from the animals directly from the anus to avoid contamination of the faeces on 58, 100 and 133 days after the start of the study to investigate the microbiota composition. The dominant animals had higher gains during the growing period that the subordinate. In addition, they were performing more visits to the feeder throughout the day. Differential abundance patterns were observed in five bacterial genera, Oliverpabstia, Peptococcus, and Faecalbacterium being more abundant in dominant animals and Holdemanella and Acetitomaculum being overrepresented in subordinate ones. This microbial biomarker accurately classified dominant versus subordinate groups of samples with an AUC of 0.92.

Homeopathy is widely used as a complementary therapy, but its effects on the behavior of production animals remain underexplored. This study evaluated the influence of a homeopathic complex on the behavior of castrated male and female piglets in the nursery phase. The experiment lasted 35 days and involved 105 animals. Piglets were allotted to five treatments in a completely randomized block design with seven replicates using three piglets per experimental unit. Tested treatments were: negative control—basal diet without additives; basal diets with 4.5, 6.0, 7.5, and 9.0 kg/ton of the homeopathic complex in the feed. Behavioral tests included open field (OF), novel object (NO), sociability, discriminative learning, judgment bias, and reactivity during weighing (RDW). Vocalizations were lower in females than males during the OF test (p = 0.016). In the RDW test, a trend was identified (p = 0.076): as the level of the homeopathic complex increased, escape attempts decreased in females and increased in males (sex × treatment interaction). Females also showed greater resistance to movement (p = 0.018). Our study suggests that the homeopathic complex does not impact the behavior of castrated male and female nursery piglets. The findings further illustrate that the sex of the animals affects their behavior, with females displaying higher levels of inactivity compared to castrated male piglets.

Although its use remains controversial, homeopathy has been proposed as an integrative approach alongside conventional medicine. This systematic review aimed to validate the use of homeopathy in veterinary using randomized controlled trials as the gold standard methodology. We performed a broad bibliographic search on the use of homeopathy in veterinary medicine published between 2016 and 2023, following the prerequisites and protocol established by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) and Cochrane Training. All searched studies were excluded if they did not fit the chosen methodology. Studies were identified based on their data and passed through a selection process. The selected studies were then assessed for risk of bias. The initial database search yielded 161 documents. Of these, 126 studies were excluded because they were not within the scope of the review, either by title or In total, 35 articles remained and underwent a data extraction process followed by study selection. Due to its methodologies, many studies with high sampling densities, encompassing numerous species and diseases, were not included in this review. Eight articles met the requirements of the present study. The articles predominantly focused on diseases, which may be attributed to the fact that treating such diseases makes it easier to validate the use of homeopathics in veterinary medicine, rather than solely employing it for prevention, as observed in the majority of the outcomes. Only four studies exhibited an overall low risk of bias. There is a scant number of robust evidence for veterinary homeopathy. With that, further randomized controlled trials involving the same species are warranted to valitade its use; the limited number of articles did not allow us to conduct a meta-analysis. This systematic review illustrates the need for a better description of the methodologies used in these studies. Embora seu uso permaneça controverso, a homeopatia tem sido proposta como uma abordagem integrativa ao lado da medicina convencional. Esta revisão sistemática teve como objetivo validar o uso da homeopatia na medicina veterinária utilizando ensaios clínicos randomizados como metodologia de referência. Uma ampla pesquisa bibliográfica foi realizada em busca de estudos publicados entre os anos de 2016 e 2023, seguindo os pré-requisitos e protocolos estabelecidos pelo Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) e treinamento Cochrane. Estudos foram excluídos caso não se enquadrassem na metodologia escolhida. Os trabalhos foram identificados com base em seus dados e passaram por um processo de seleção. Estudos selecionados foram então avaliados quanto ao risco de viés, sendo que a busca inicial no banco de dados resultou em 161 documentos. Desses, 126 foram excluídos porque não estavam dentro do escopo da revisão, seja pelo título ou resumo. No total, 35 artigos permaneceram e passaram por um processo de extração de dados seguido da seleção. Devidos às suas metodologias, muitos estudos com altas densidades amostrais, abrangendo inúmeras espécies e doenças, não foram incluídos nesta revisão. Oito artigos atenderam aos requisitos da revisão. Os trabalhos focaram predominantemente em doenças, o que pode ser atribuído ao fato de que tratar tais doenças facilita a validação do uso de homeopáticos na medicina veterinária, ao invés de empregá-los exclusivamente para prevenção, como observado na maioria dos resultados. Apenas quatro artigos apresentaram, em geral, um baixo risco de viés. Há um número escasso de evidências positivas robustas para a homeopatia veterinária; mais ensaios clínicos randomizados envolvendo a mesma espécie são necessários para validar o seu uso. O número limitado de artigos não permitiu a condução de uma metanálise, sendo que essa revisão sistemática destaca a necessidade de uma melhor descrição das metodologias utilizadas nesses estudos.