APPLICATION OF MICROSATELLITE MARKERS IN IDENTIFICATION AND PARENTAGE ASSIGNMENT OF SHEEP

The accuracy of the parentage reference is the early step of information needed for genotyping study.Inaccurate data of recording sheep numbers is often occurred. Sometimes, we found sheep or lambs with uncertain original parents. This study was designed to identify the parentages of sheep and to find the putative parents of lambs. Using an advance DNA technology in molecular genetics particularly in genotyping study, those purposes can be clarified. DNA of sheep were isolated from fresh blood samples in EDTA using a high salt method. A concentration of 50ng/(il DNA was used for amplification. Several microsatellite markers were applied in the amplification. Using a DNA analyser and sequencer, PCR products were analysed to look at the figures of alleles (bands). Results showed that using microsatellite markers could inform that parents of several experimental lambs were incorrect. It was found that putative parents of some lambs were generated from incorrect parents. This study suggests that microsatellite marker can be used to clarify unknown original parents

Application of Microsatellite Markers in Identification and Parentage Assignment of Sheep

The accuracy of the parentage reference is the early step of information needed for genotyping study.Inaccurate data of recording sheep numbers is often occurred. Sometimes, we found sheep or lambs with uncertain original parents. This study was designed to identify the parentages of sheep and to find the putative parents of lambs. Using an advance DNA technology in molecular genetics particularly in genotyping study, those purposes can be clarified. DNA of sheep were isolated from fresh blood samples in EDTA using a high salt method. A concentration of 50ng/(il DNA was used for amplification. Several microsatellite markers were applied in the amplification. Using a DNA analyser and sequencer, PCR products were analysed to look at the figures of alleles (bands). Results showed that using microsatellite markers could inform that parents of several experimental lambs were incorrect. It was found that putative parents of some lambs were generated from incorrect parents. This study suggests that microsatellite marker can be used to clarify unknown original parents

Mapping quantitative trait loci (QTL) in sheep. I. A new male framework linkage map and QTL for growth rate and body weight

A male sheep linkage map comprising 191 microsatellites was generated from a single family of 510 Awassi-Merino backcross progeny. Except for ovine chromosomes 1, 2, 10 and 17, all other chromosomes yielded a LOD score difference greater than 3.0 between the best and second-best map order. The map is on average 11% longer than the Sheep Linkage Map v4.7 male-specific map. This map was employed in quantitative trait loci (QTL) analyses on body-weight and growth-rate traits between birth and 98 weeks of age. A custom maximum likelihood program was developed to map QTL in half-sib families for non-inbred strains (QTL-MLE) and is freely available on request. The new analysis package offers the advantage of enabling QTL × fixed effect interactions to be included in the model. Fifty-four putative QTL were identified on nine chromosomes. Significant QTL with sex-specific effects (i.e. QTL × sex interaction) in the range of 0.4 to 0.7 SD were found on ovine chromosomes 1, 3, 6, 11, 21, 23, 24 and 26