Study of the indirect genetic effect of social interaction on traits obtained in feed efficiency tests of Nellore cattle

• Grant number: 24/05697-4
• Support Opportunities: Scholarships in Brazil - Doctorate
• Start date: August 01, 2024
• End date: February 28, 2026
• Field of knowledge: Agronomical Sciences - Animal Husbandry - Genetics and Improvement of Domestic Animals
• Principal Investigator: Maria Eugênia Zerlotti Mercadante
• Grantee: Júlia de Paula Soares Valente
• Host Institution: Instituto de Zootecnia. Agência Paulista de Tecnologia dos Agronegócios (APTA). Secretaria de Agricultura e Abastecimento (São Paulo - Estado). Nova Odessa , SP, Brazil

Abstract

Production systems commonly use animal species that exhibit gregarious behavior. This behavior is characterized by the formation of social interactions and relationship bonds between group members. However, classical animal genetic improvement does not take into account the social effect of an individual on their groupmates in theanimal model. An alternative modeling approach involves adding social interactions as an additional random effect into the model, assuming that a trait can be controlled either by direct genetic effect due to the animal's genes orby indirect genetic effect due to genes expressed by its group mates. Therefore, the present research project aims to evaluate the indirect genetic effect of social interactions on feed efficiency traits in Nelore cattle. The specificobjectives are to determine the best time interval between the departure of an animal and the subsequent entry of another animal into the same trough that occurred from an agonistic interaction between the same animals to predict replacement events in the trough with interaction agonistic interactions from electronic trough data anddetermine whether data obtained from electronic troughs can be used to identify agonistic interactions in Nellore steers. The information to be used was obtained from 1,157 Nelore steers that participated in 16 feed efficiency tests (FET) that occured between 2013 and 2023 at the Institute of Animal Science, Sertãozinho, SP, Brazil. Residual feed intake will be estimated as the residual of the linear regression of dry matter intake on average daily gain and metabolic body weight. Data to estimate social interactions between animals from the same FET will be obtained from the substitutions that occurred in the trough as a result of agonistic interactions (e.g., pushing, headbutting). The interactions will be identified based on data from feeding events obtained by the electronic troughs during the FETs that occurred between the years 2013 and 2023. A replacement criterion will be considered to determine a replacement with an agonistic interaction in the trough. The replacement criterion will be the shortest time interval between the departure of an animal and the entry of another animal into the same trough that characterizes a replacement that occurred due to an agonistic interaction. Two models will beused to estimate the variance components and genetic values based on the inclusion of the direct genetic and indirect genetic effect. With the development of this project, it is expected that the components of genetic (co)variance in different animal models, including direct and indirect genetic effects in Nelore cattle, will beestimated for comparison. The aim is to enable the use of data from electronic troughs to obtain agonistic interactions in the feeding area through the application of the replacement criteria for Nelore cattle. This approach will facilitate the acquisition of social behavior data and,consequently, the application of this information in models that use indirect genetic effects. Also, it is expected that the incorporation of the indirect genetic effect willimprove the selection process of feed efficiency traits.

Scientific publications

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

RODRIGUES, GUSTAVO R. D.; CYRILLO, JOSLAINE N. S. G.; MOTA, LUCIO F. M.; SCHMIDT, PATRICIA I.; VALENTE, JULIA P. S.; OLIVEIRA, EDUARDA S.; ALBUQUERQUE, LUCIA G.; BRITO, LUIZ F.; MERCADANTE, MARIA E. Z.. Effect of genomic regions harboring putative lethal haplotypes on reproductive performance in closed experimental selection lines of Nellore cattle. SCIENTIFIC REPORTS, v. 15, n. 1, p. 15-pg., 2025-02-03. (18/20026-8, 24/01909-7, 24/05697-4, 21/09942-5, 17/10630-2, 23/11176-4, 22/11852-7, 17/50339-5)

RODRIGUES, GUSTAVO R. D.; BRITO, LUIZ F.; MOTA, LUCIO F. M.; CYRILLO, JOSLAINE N. S. G.; VALENTE, JULIA P. S.; BENFICA, LORENA F.; NETO, JOAO B. SILVA; BORGES, MARCELO S.; MONTEIRO, FABIO M.; EL FARO, LENIRA; et al. Genome-wide association studies and functional annotation of pre-weaning calf mortality and reproductive traits in Nellore cattle from experimental selection lines. BMC Genomics, v. 25, n. 1, p. 17-pg., 2024-12-18. (24/01909-7, 24/05697-4, 17/10630-2, 23/11176-4, 22/11852-7, 17/50339-5)