title: Inbreeding depression in Zebu cattle traits.
abstract: The productivity of herds may be negatively affected by inbreeding depression, and it is important to know how intense is this effect on the livestock performance. We performed a comprehensive analysis involving five Zebu breeds reared in Brazil to estimate inbreeding depression in productive and reproductive traits. Inbreeding depression was estimated for 13 traits by including the individual inbreeding rate as a linear covariate in the standard genetic evaluation models. For all breeds and for almost all traits (no effect was observed on gestation length), the performance of the animals was compromised by an increase in inbreeding. The average inbreeding depression was -0.222% and -0.859% per 1% of inbreeding for linear regression coefficients scaled on the percentage of mean (βm) and standard deviation (βσ), respectively. The means for βm(and βσ) were -0.269% (-1.202%) for weight/growth traits and -0.174% (-0.546%) for reproductive traits. Hence, inbreeding depression is more pronounced in weight/growth traits than in reproductive traits. These findings highlight the need for the management of inbreeding in the respective breeding programmes of the breeds studied here.
authors.affiliation: Grupo de Melhoramento Animal de Mato Grosso (GMAT), Instituto de Ciências Agrárias e Tecnológicas, Campus Universitário de Rondonópolis, Universidade Federal de Mato Grosso, Rondonópolis, MT, Brazil.
authors.forename: R J
authors.initials: RJ
authors.lastname: Pereira
authors.affiliation: Grupo de Melhoramento Animal de Mato Grosso (GMAT), Instituto de Ciências Agrárias e Tecnológicas, Campus Universitário de Rondonópolis, Universidade Federal de Mato Grosso, Rondonópolis, MT, Brazil.
authors.forename: M L
authors.initials: ML
authors.lastname: Santana
authors.affiliation: Grupo de Melhoramento Animal de Mato Grosso (GMAT), Instituto de Ciências Agrárias e Tecnológicas, Campus Universitário de Rondonópolis, Universidade Federal de Mato Grosso, Rondonópolis, MT, Brazil.
authors.forename: D R
authors.initials: DR
authors.lastname: Ayres
authors.affiliation: Grupo de Melhoramento Animal de Mato Grosso (GMAT), Instituto de Ciências Agrárias e Tecnológicas, Campus Universitário de Rondonópolis, Universidade Federal de Mato Grosso, Rondonópolis, MT, Brazil.
authors.forename: A B
authors.initials: AB
authors.lastname: Bignardi
authors.affiliation: Embrapa Gado de Corte, Campo Grande, MS, Brazil.
authors.forename: G R O
authors.initials: GR
authors.lastname: Menezes
authors.affiliation: Embrapa Gado de Corte, Campo Grande, MS, Brazil.
authors.forename: L O C
authors.initials: LO
authors.lastname: Silva
authors.affiliation: Associação Brasileira dos Criadores de Zebu, Uberaba, MG, Brazil.
authors.forename: C H C
authors.initials: CH
authors.lastname: Machado
authors.affiliation: Associação Brasileira dos Criadores de Zebu, Uberaba, MG, Brazil.
authors.forename: L A
authors.initials: LA
authors.lastname: Josahkian
authors.affiliation: Faculdade de Ciências Agrárias e Veterinárias, Universidade Estadual Paulista, Jaboticabal, SP, Brazil.
authors.forename: L G
authors.initials: LG
authors.lastname: Albuquerque
mesh_terms: D000818:Animals; D001938:Brazil; D002417:Cattle / Q000145:classification* / Q000235:genetics* / Q000502:physiology; D007178:Inbreeding; D008460:Meat; D008892:Milk
keywords: Beef cattle; calving performance; dairy cattle; growth; reproduction