Analysis of the supplementation of the microencapsulated antimicrobial peptide Ctx(Ile²¹)-Ha on performance and intestinal health of swines

• Grant number: 24/23197-9
• Support Opportunities: Scholarships in Brazil - Master
• Start date: April 01, 2025
• End date: March 31, 2027
• Field of knowledge: Agronomical Sciences - Animal Husbandry - Animal Nutrition and Feeding
• Principal Investigator: Eduardo Festozo Vicente
• Grantee: Sophia Silva Carrijo
• Host Institution: Faculdade de Ciências e Engenharia. Universidade Estadual Paulista (UNESP). Campus de Tupã. Tupã , SP, Brazil
• Associated research grant: 21/06706-9 - Antimicrobial peptides: expanding the horizons for animal production performance optimization, AP.JP2

Abstract

Swine production is an important economic activity in farming systems worldwide, especially in tropical and subtropical areas, where climatic conditions are not very favorable for pig production. In these locations, the animal production intensification, high environmental temperatures and humidity, associated with the degree of sanitary conditions of the facilities, frequently expose these animals to stressful conditions and health challenges. Consequently, these situations promote weakness of the immune system, propitiating proliferation and dissemination of pathogens. This results in a considerable variability in the productive response of pigs, making the use of antibiotics demanded. In this context, this study proposes the application of the AMP-formulations in swines. Firstly, the antimicrobial peptide Ctx(Ile21)-Ha (AMP) will be manually synthesized at School of Sciences and Engineering (FCE/Unesp Tupã), purified and characterized in order to obtain enough mass to the next steps and, after that, microencapsulaton process of the AMP will be performed. The in vivo experiments in swines will be carried out at LabSui at the Unesp Animal Science Department (FCAV/Unesp Jaboticabal). The trial will use 30 pigs (in a single repetition) in the growing phase. The adaptation phase will last at least 14 days, or until the pigs reach 25 kg of body weight (BW) in the beginning of the trial. To simulate a moderate sanitary challenge, two oral doses containing 108 CFU of Enterotoxigenic E. coli (ETEC) K88 will be evaluated. The experiment will be conducted in 14 days, being the treatments positive control (n = 10), negative control (n = 10) and treated, which will receive a dose of AMP-formulation microparticles (n = 10) from 20 to 50 mg per kg of feed, being each pig will be an experimental unit. The following experimental measurements will be carried out to evaluate the performance of the animals: i) feed consumption, ii) body weight of all animals, iii) body temperature, iv) body composition, v) blood and feces samples, vi) Salmonella fecal shedding and vii) fecal microbiome characterization. Statistical analyses will be analyzed using the SAS PROC MIXED testing the fixed effects of the experimental diets, sanitary conditions, time of supplementation, and the interactions between these factors. The mixed model will include the random effect of successive measurements of a variable on the same animal using covariance structures that provide the smallest AIC. The effect will be considered significant if P < 0.05.