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| Author(s): |
Luís Gustavo Girardi Figueiredo
Total Authors: 1
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| Document type: | Doctoral Thesis |
| Press: | Pirassununga. |
| Institution: | Universidade de São Paulo (USP). Faculdade de Zootecnica e Engenharia de Alimentos (FZE/BT) |
| Defense date: | 2005-08-04 |
| Examining board members: |
Joanir Pereira Eler;
Júlio Cesar de Carvalho Balieiro;
Flávio Vieira Meirelles;
Henrique Nunes de Oliveira;
Luciana Correia de Almeida Regitano
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| Advisor: | Joanir Pereira Eler |
| Abstract | |
The aim of this research was to estimate the effect of the maternal lineage and mitochondrial DNA inclusion in the genetic evaluation model for growth traits, to evaluate the satellite DNA effect in these traits and to estimate genetic parameters for carcass traits and age at first calving. Blood samples were collected to mtDNA analysis from 457 Nellore cattle. Growth traits were analyzed from 14,432 production data and 16,561 pedigree data. Reproductive and carcass traits were analyzed from 4,621 age at first calving data and 951 loin-eye area and subcutaneous fat thickness data related to 7,135 pedigree data. Maternal lineage and mitochondrial DNA estimative were analyzed under 5 different models, (co)variance components for age at first calving and carcass traits were estimated in single and multiple-trait. There were no significant effects of maternal lineage or mitochondrial DNA related to production traits, but animals harboring Bos taurus mtDNA showed a low superiority on breeding values average for growth traits and animals harboring satellite DNA B pattern also showed a low superiority related to the other patterns. Further studies are suggested to evaluate the backfat thickness precocity effect related to sexual precocity. (AU) | |