Effects of different feeding strategies during mid-gestation of sows on body condition, milk composition, and litter performance

• Grant number: 25/09584-2
• Support Opportunities: Scholarships abroad - Research Internship - Scientific Initiation
• Start date: September 18, 2025
• End date: January 17, 2026
• Field of knowledge: Agronomical Sciences - Veterinary Medicine
• Principal Investigator: Cesar Augusto Pospissil Garbossa
• Grantee: Flávia Stievano de Souza Tavares
• Supervisor: Geert Paul Jules Janssens
• Host Institution: Faculdade de Medicina Veterinária e Zootecnia (FMVZ). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Institution abroad: Ghent University (UGent), Belgium
• Associated to the scholarship: 24/22402-8 - Chlorhexidine Nanoparticles: A New Molecule for Improving Microbiological Quality of Feed and Performance of Piglets in the Nursery Phase, BP.IC

Abstract

The body condition of gestating sows plays a crucial role in determining their productive and reproductive performance, while also directly influencing fetal development and the subsequent performance of the litter throughout the production cycle. During gestation, nutrition is essential for the build up and mobilization of body reserves-particularly protein and fat-to support proper embryonic growth, placental efficiency, and subsequent milk production. Parameters such as backfat thickness (BFT) and loin depth (LD) are commonly used to assess body condition, serving as indicators of protein and lipid metabolism in sows, and are associated with birth weight, milk composition, and postnatal survival. It is well established that mid-gestation is a critical phase for modulating body condition. In this context, the lack of well-defined nutritional strategies for maintaining optimal body condition in sows can lead to long-lasting impacts on piglet health and development. Therefore, this study aims to evaluate the effects of different feeding regimens during mid-gestation on sow body condition, milk composition, and litter performance. A total of 140 RASE sows will be assigned to three dietary treatments: sows fed at requirement (REQ), sows fed 25% below requirement (LOW), and sows fed 25% above requirement (EXTR), with requirement calculated by the model proposed by Dourmad et al. (2017). On day 35 of gestation, sows will be blocked by weight, and parity order. Feeding regimens will be implemented from day 35 to day 85 of gestation (mid-gestation), using individual electronic feeders. Body condition parameters will be assessed using an ultrasound device on days 0, 35, 63, 85, 110 of gestation, and on day 28 of lactation (weaning). Milk samples collected on days 7 and 28 of lactation will be analyzed for composition (protein, fat, and lactose). During farrowing, total born, live-born, stillborn, and mummified piglets will be recorded. After birth, piglets will be monitored until weaning to assess body weight, pre-weaning mortality, and average daily gain.