ASSESSMENT OF THE IMPACT THAT STRESS AND SYSTEMIC INFLAMMATION DURING PARTURITION HAVE ON THE SOW'S WELFARE

• Grant number: 24/20463-0
• Support Opportunities: Scholarships abroad - Research Internship - Scientific Initiation
• Start date: January 21, 2025
• End date: May 19, 2025
• Field of knowledge: Agronomical Sciences - Veterinary Medicine - Animal Reproduction
• Principal Investigator: Cesar Augusto Pospissil Garbossa
• Grantee: Roberta Yukari Hoshino
• Supervisor: Stefan Bjorkman
• Host Institution: Faculdade de Medicina Veterinária e Zootecnia (FMVZ). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Institution abroad: University of Helsinki, Finland
• Associated to the scholarship: 24/06623-4 - Supply of nesting material as an alternative to promote welfare and productive efficiency of hyperprolific gilts, BP.IC

Abstract

Farrowing is an important and delicate moment in swine production. It is accompanied by significant physiological challenges, such as stress and systemic inflammation. These challenges, when uncontrolled in sows, can affect immunity and damage blood vessels, increasing the risk of infection. Additionally, they disrupt the endocrine and metabolic balance, which appears to be the main cause for the development of postpartum dysgalactia syndrome (PPDS). Therefore, it is of utmost importance to understand how these events affect the sow's homeostasis, as this correlation is currently unclear. For this reason, this study aims to evaluate the effects of systemic stress and inflammation during parturition on the sow's metabolic and endocrine state, particularly their influence on postpartum infection risk and antibiotic use. Forty-five crossbred sows (Danish Yorkshire and Landrace) that are in their second to fourth parities will be utilized. We will sample 10 to15 animals per batch, and three to four batches altogether. The sows will be followed from parturition through one-week post-farrowing, with saliva and blood samples collected on two key days (1 and 4 days post-farrowing) to assess stress biomarkers (cortisol, chromogranin A), oxidative stress biomarkers (ROS, TBARS), inflammatory markers (IL-6, TNF-¿), metabolic markers (IGF-1, T4/fT4 glucose) and hormones important for maternal behavior and lactation (Progesterone, Prolactin). We will conduct a general clinical examination of sows on both sampling days and an ultrasound examination of their uterus at the second sampling day. Outcome measures include the occurrence of postpartum reproductive diseases, antibiotic use, and the correlation between procalcitonin levels and postpartum uterine infections. All litters included in the present study will be weighed at both sampling days (after litter management strategies, e.g. cross fostering, has been conducted) and at weaning to evaluate litter performance and its association with the sow's biomarkers of stress and inflammation. Further, a sample of salivary biomarker for bacterial systemic infection (procalcitonin) and an ultrasound of the uterus, as indicators for bacterial infection of the uterus (i.e., endometritis / metritis), will be conducted on the second sampling day, and their associations with sow's stress and inflammatory status investigated.