RESUMO
The unique Pere David's (Elaphurus davidianus) x red deer (Cervus elaphus) backcross hybrid has been used to search for evidence of quantitative trait loci (QTL) for antler pubertal (date and live weight at pedicle initiation) and antler seasonality (date of antler cleaning and casting) traits in temperate species of deer. Analyses using marker information revealed evidence for a QTL for date at pedicle initiation (LOD = 3.7) and live weight at pedicle initiation (LOD = 3.1). These QTL explained 13% and 11% of the phenotypic variance in these traits, respectively.
Assuntos
Quimera/genética , Cervos/genética , Característica Quantitativa Herdável , Animais , Mapeamento Cromossômico/veterinária , Cervos/crescimento & desenvolvimento , Feminino , Marcadores Genéticos , Genótipo , Masculino , Fenótipo , Estações do AnoRESUMO
Interspecies hybrids between Père David's deer (Elaphurus davidianus) and red deer (Cervus elaphus) have proved to be a powerful resource in the search for quantitative trait loci (QTL) in deer. Several regions of the genome with significant effects on live weight and growth rates in backcross hybrids were detected. These include putative QTL for 6-month live weight (LOD 3.90) on linkage group 12, for 14-month live weight (LOD 3.19) on linkage group 1, three putative QTL for growth rate from 3 to 6 months (LOD 4.19 on linkage group 12, LOD 3.92 on linkage group 12, and LOD 3.34 on linkage group 5). In addition, linkage groups 20 and 1 appear to be associated with live weight traits between 9 and 16 months. The variance in traits explained by these QTL ranged between 5.3% and 11.2%. Allele substitution with Père David's alleles at different loci had both positive and negative effects on live weights and growth rates.
Assuntos
Peso Corporal/genética , Cervos/genética , Característica Quantitativa Herdável , Animais , Mapeamento Cromossômico/veterinária , Cervos/crescimento & desenvolvimento , Feminino , Marcadores Genéticos , Genótipo , Masculino , FenótipoRESUMO
Molecular methods which identify species-specific genetic markers are valuable for identification and genetic analysis of hybrid deer. We have used a variety of molecular techniques to compare Père David's deer Elaphurus davidianus, red deer Cervus elaphus scotticus and North American wapiti C. e. manatobensis. In total, these analyses have identifed over 300 markers in which Père David's deer sires are distinct from farmed red deer and over 100 markers in which wapiti sires differ from red deer. Subsets of these markers have been used to identify hybrids on farms, and to estimate the proportion of red deer and wapiti in hybrid animals. Analysis of the segregation of the species-specific alleles in 352 backcross 1/4 Père David's, 3/4 red deer hybrids has produced a deer genetic linkage map which describes the chromosomal grouping and order of the markers. Correlation of the variability in phenotypic traits with marker segregation in the back-cross hybrids has located genes which influence variation in gestation length, pedicle-initiation, birth weight, growth rate and a variety of morphological traits in Père David's deer x red deer hybrids. Such genetic analyses can now be extended, using new marker technologies, to more closely related taxa, such as farmed red deer and wapiti hybrids, and potentially analyse natural hybrid zones.
Assuntos
Criação de Animais Domésticos , Animais Selvagens/genética , Cervos/genética , Marcadores Genéticos , Variação Genética/genética , Animais , Cruzamento , Cruzamentos Genéticos , Feminino , Hibridização Genética , Masculino , Repetições de Microssatélites/genética , Nova Zelândia , Polimorfismo Genético/genética , Polimorfismo de Fragmento de Restrição , Característica Quantitativa Herdável , Especificidade da EspécieRESUMO
Interspecies hybrids provide unique opportunities for fundamental genetic analyses and for genetic improvement of farmed deer. We have bred F1 hybrids by artificial insemination of red deer hinds (Cervus elaphus) with semen from Père David's deer (Elaphurus davidianus). The male and female F1 Père David deer x red deer hybrids were fertile and in matings with red deer have produced over 300 viable backcross hybrids. DNA was collected from the backcross progeny as an international reference panel for gene linkage mapping and to investigate associations between segregating species-specific genetic markers and phenotypic traits. We have measured a range of phenotypic traits in the backcross hybrids and red deer. Several traits appear suitable for genetic analysis using mapped genetic markers, including gestation length, growth rate, live weight, head morphometrics, and tail length. Typically these traits show a large difference between Père David's deer and red deer and a high variance in the backcross so that many individuals have a phenotype outside the range observed in red deer.
