Effect of dietary supplementation with functional amino acids (Thr, Met and Trp) in suboptimal health challenged pigs with Salmonella typhimurium

• Grant number: 20/15797-5
• Support Opportunities: Scholarships in Brazil - Doctorate (Direct)
• Start date: March 01, 2021
• End date: October 31, 2023
• Field of knowledge: Agronomical Sciences - Animal Husbandry - Animal Nutrition and Feeding
• Principal Investigator: Luciano Hauschild
• Grantee: Ismael França
• Host Institution: Faculdade de Ciências Agrárias e Veterinárias (FCAV). Universidade Estadual Paulista (UNESP). Campus de Jaboticabal. Jaboticabal , SP, Brazil
• Associated research grant: 18/15559-7 - Precision nutrition for sanitary challenged pigs reared in hot climate areas, AP.JP2

Abstract

The activation of the immune system demands a massive contribution of Amino Acids (AA), which can come from ingested feed or metabolized from the muscular tissues. Challenging hygienic-sanitary conditions and stress factors result in recurrent induction of immune response, which can be considered one of the main factors influencing animal performance variation, especially in the initial growth phase (between 60-70 days of age). In this context, amino acid supplementation and health management strategies that potentially mitigate a suboptimal animal health condition may result in lower variation in performance. The objective of this study will be to evaluate the effect of extra supplementation using a combination of functional AA (Threonine, Methionine, and Tryptophan) on the performance, body composition and physiological and metabolic responses in suboptimal health pigs challenged with Salmonella typhimurium in the growth phase. To accomplish that, an experiment will be conducted where two sanitary conditions will be simulated in two experimental barns: good (animals from farms with good health history and hygiene standards) or challenged (mixing animals from farms with good health history and hygiene standards and animals from farms with poor health history and low standard of hygiene plus an inoculation with Salmonella typhimurium). The farms will be categorized through the analysis of previous batches performance and the sanitary aspects of the facilities, considering the performance indicators, history of diseases and quality of health management. Sixty female pigs (25 kg of initial weight) of lines with high genetic potential will be acquired from a single farm with good sanitary history. They will be housed in two experimental barns (30 animals/barn) to simulate two different health status (good or suboptimal). At the beginning of the growth phase, in order to simulate a poor sanitary condition in one of the barns, a group of 30 female pigs from a farm with a poor sanitary history will be housed with the animals acquired from the farm with good sanitary conditions. In addition, after mixing batches of pigs from different sanitary conditions, the pigs in this barn will be immunologically challenged with Salmonella typhimurium. Thus, the 60 animals coming from a good sanitary condition will be distributed in a 2×2 factorial design: 2 levels of functional AA supplementation (growth phase, 0% and 20% above the NRC recommended requirements for Thr, Met and Trp) and 2 sanitary conditions (good or challenged, during the growing phase). Each treatment will have 15 repetitions and each animal will be considered an experimental unit. The diets will be similar in both sanitary conditions and formulated according to the nutritional requirements recommended by the NCR (2012). The experiment will last 28 days. The variables to be studied will be performance; feeding behavior; body composition (evaluated with the use of Double X-ray Absorptiometry equipment - DXA); physiological and metabolic indicators (evaluated through blood analyses from animals during the growing phase). (AU)