Ganho genético monetário para resistência ao carrapato com diferentes acurácias.

SIEPE

Delineamento de esquemas de seleção genômica para resistência ao carrapato bovino.

CONGREGA

Linkage disequilibrium, persistence of phase and effective population size estimates in Hereford and Braford cattle.

The objective of this study was to estimate LD levels, persistence of phase and effective population size in Hereford and Braford cattle populations sampled in Brazil.Article 32

Estimation of linkage disequilibrium, persistence of phase and effective population size of Brazilian Hereford and Braford breeds.

A set of 41,241 SNP genotypes from 2,435 Hereford (HH) and Braford (BO) bovines were analyzed to estimate linkage disequilibrium (LD) levels, persistence of phase and effective population size of these populations. LD levels were estimated using the squared correlation of alleles at two loci (r2) at varying distances. Average r2 between adjacent SNP was 0.21 for HH and 0.16 for BO. Average inter-marker distance was 61 kb in both breeds. Useful LD values (r2>0.2) were observed at 0-60 kb bins in HH and 0-20 kb bins in BO. Breeds demonstrated moderate to strong persistence of phase at all distances (range=0.53- 0.97). The greatest phase correlations (r>0.9) were found in 0-50 kb bins. LD estimates decreased rapidly with increasing distances between SNPs, however, useful LD was observed in genomic regions spanning up to ~50 kb

Estimation of linkage disequilibrium, persistence of phase and effective population size of Brazilian Hereford and Braford breeds.

A set of 41,241 SNP genotypes from 2,435 Hereford (HH) and Braford (BO) bovines were analyzed to estimate linkage disequilibrium (LD) levels, persistence of phase and effective population size of these populations. LD levels were estimated using the squared correlation of alleles at two loci (r2) at varying distances. Average r2 between adjacent SNP was 0.21 for HH and 0.16 for BO. Average inter-marker distance was 61 kb in both breeds. Useful LD values (r2>0.2) were observed at 0-60 kb bins in HH and 0-20 kb bins in BO. Breeds demonstrated moderate to strong persistence of phase at all distances (range=0.53-0.97). The greatest phase correlations (r>0.9) were found in 0-50 kb bins. LD estimates decreased rapidly with increasing distances between SNPs, however, useful LD was observed in genomic regions spanning up to ~50 kb

Efeito da resistência de bovinos ao carrapato sobre a eficiência reprodutiva de fêmeas de rhipicephalus (boophilus) microplus.

Foram avaliadas amostras de teleóginas coletadas em 40 novilhas Braford classificadas de acordo com os valores genéticos para a resistência ao carrapato e expostas a quatro infestações artificiais, para verificar os efeitos da resistência sobre características relacionadas à capacidade reprodutiva dos parasitos. Fêmeas ingurgitadas em novilhas suscetíveis apresentaram maior capacidade de postura e maiores índices de eficiência reprodutiva que teleóginas ingurgitadas em novilhas resistentes