Effect of selection for growth at different ages on energy consumption in the Nellore cattle

• Grant number: 09/04490-7
• Support Opportunities: Scholarships in Brazil - Doctorate
• Effective date (Start): April 01, 2010
• Effective date (End): July 31, 2012
• Field of knowledge: Agronomical Sciences - Animal Husbandry - Genetics and Improvement of Domestic Animals
• Principal Investigator: Henrique Nunes de Oliveira
• Grantee: Iara Del Pilar Solar Diaz
• Host Institution: Faculdade de Ciências Agrárias e Veterinárias (FCAV). Universidade Estadual Paulista (UNESP). Campus de Jaboticabal. Jaboticabal , SP, Brazil

Abstract

This paper will study the predicted effect of selection on growth traits at different life stages of animal and estimate their effect on energy requirement in a herd of complete breeding cycle (cow-calf, rearing, fattening), by the estimation of energy requirements of various animals categories. The data to be used in the estimation of the parameters needed to estimate the response to selection were provided by the National Association of Breeders and Researchers (NABR), which has a total of 874.624 million Nellore animals registered, distributed in 13 states. In this research, will be only used data from animals raised exclusively on pasture and belonging of Sao Paulo state. Weighing information during Nellore stayability will be used, where females weights are taken into adulthood and males until around 18 or 24 months. Estimates of genetic parameters of growth will be obtained by random regression models. The responses to selection will be calculated for each type of animal and age according to the prediction equations to the period of two generations. The generation interval will be estimated based on information from herds. The energy requirements of animals in each category will be estimated by prediction equations available in the NRC considering each age, physiological state, weight and weight gain until the next stage. Using reproductive and mortality parameters of Nellore, obtained in our data of livestock, or available in the literature and using average weight data for each age of animal of herds studied as a base, will be established simulated herds numerically stable, which will be subject to selection for growth at different ages. Once calculated the expected responses in each herd simulated to the direct and indirect selection for each animal category, will be estimated the energy requirements of each category and the increased weigh and gain effect on these requirements inside each category and the consumption of energy in the whole herd every year. Also, will be estimated kg of carcass produced each year based on parameters of literature. After that, herds subjected to different selection criteria will be compared to verify the consequences of selection for each weight in terms of the relationship between kg of carcass produced and energy consumption.

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)

SOLAR DIAZ, IARA DEL PILAR; FRAMARTINO BEZERRA, LUIS ANTONIO; LOBO, RAYSILDO BARBOSA; DE ARAUJO NETO, FRANCISCO RIBEIRO; FERREIRA DE CAMARGO, GREGORIO MIGUEL; ROCHA DA CRUZ, VALDECY APARECIDA; COSTA, RAPHAEL BERMAL; DE OLIVEIRA, HENRIQUE NUNES. Selection effect for growth traits on energy requirements in beef Nelore steers. TROPICAL ANIMAL HEALTH AND PRODUCTION, v. 54, n. 4, p. 9-pg., 2022-08-01. (09/04490-7)

Academic Publications

(References retrieved automatically from State of São Paulo Research Institutions)

DIAZ, Iara Del Pilar Solar. Efeito da seleção para crescimento em diferentes idades sobre o consumo de energia em animais da raça Nelore. 2012. Doctoral Thesis - Universidade Estadual Paulista (Unesp). Faculdade de Ciências Agrárias e Veterinárias. Jaboticabal Jaboticabal.