Efeitos genéticos aditivos e não-aditivos em características de crescimento, reprodutivas e habilidade materna em ovinos das raças Santa Inês, Somalis Brasileira, Dorper e Poll Dorset

Abstract

RESUMO -Efeitos genético aditivo, de dominância e de recombinação em cruzamentos entre as raças Santa Inês (SI), Somalis Brasileira (So), Dorper (Do) e Poll Dorset (Po) foram estimados para as características de crescimento, reprodutivas e de habilidade materna. Os dados foram obtidos da Gaasa e Alimentos LTDA, uma empresa que participa do Programa de ABSTRACT -Additive genetic, dominance and recombination effects in breedings among Santa Inês (SI), Brazilian Somali (So), Dorper (Do) and Poll Dorset (Po) breeds were estimated for growth, reproductive and maternal hability traits. Data were obtained from Gaasa e Alimentos LTDA, a company that participates on the Programa de Melhoramento Genético de Caprinos e Ovinos (GENECOC) coordinated by Embrapa Caprinos. Initially, 3,573 records were analyzed using the MIXED procedure of the statistical package SAS (1999). The analyses were carried out considering the effects of additive genetic difference among breeds, dominance and recombination effects. Birth weight was mainly influenced by additive genetic effects, while weaning weight and pre-weaning weight gain were influenced by non-additive genetic effects. Direct heritability estimates for birth weight was moderate indicating that there is genetic variability believable to be exploited by individual selection. In the same way, heritability estimates for the traits age at first lambing and litter total weight at birth indicated the existence of genetic variability to obtain genetic gains through selection. Genes of the Poll Dorset and Dorper breeds had an important role for a better growth performance, therefore, these breeds can be indicated as sires in the terminal breeds. The use of F1 Santa Inês × Brazilian Somali females on crossbreeding with Poll Dorset rams can lead to a better reproductive efficiency.

Seleção assistida: proposta de otimização utilizando Algoritmos Genéticos

“…A utilização da variação de dominância, no geral, não é primordial para o melhoramento de raças puras, podendo ter maior impacto em animais cruzados, nos quais os efeitos heteróticos entre raças podem ser mais explorados (PEREIRA, 2008;BARBOSA NETO et al, 2010). SANTOS, N.P.S.…”

Genetic effects on meat quality of crossbred lambs finished in confinement

“…Santa Inês and Brazilian Somalis breeds, for example, stand out because of their adaptability to Brazilian Northeastern semiarid region and ability to produce meat. F1 Lambs originated from crossing of males of these genotypes with females from undefi ned racial pattern can be an important alternative in meat production with better physical and chemical characteristics, since it can exploit the potential of complementarity, which favors the conjugation of desirable characteristics of each genetic group (Barbosa Neto et al 2010).…”

Effect of the environment and diet on the physiological variables of sheep in the Brazilian semi-arid region

“…According to Barbosa Neto et al (2010), one of the alternatives to increase Brazilian production through animal genetic improvement would be to harness the potential of different breeds, using crossbreeding selection strategies. The Dorper breed can be used for this purpose because it was created to produce meat as efficiently as possible under varied and even unfavorable environmental conditions, being able to resist and maintain a good health and body condition (ARCO, 2018).…”