UBC Theses and Dissertations
Microsatellite DNA variation in domestic ratite populations Benun, Assaf
Ostrich (Struthio camelus) farming in North America is a growing industry that recently started moving from the breeder market to the slaughter market. The domesticated ostriches, the Black (Struthio camelus var domesticus) and the Blue (S. c. australis). have been bred in South Africa and farmed in the past 150 years. More recently, another subspecies, the Red (S. c. massaicus) has been added to the farm population. The commercial importation to North America has only begun in the mid 1980s. Unlike other poultry, ostriches have a relatively long generation time, require more rearing space, and have a high per unit dollar value. Because their pedigrees have not been well kept, the genetic variation of North American ostriches is not known. Fears of inbreeding and limited heterozygosity arose from limited knowledge of the breeders background and may affect the type of genetic manipulation that will be necessary for improving production, i.e., selection, cross-breeding and inbreeding. I used 8 recently developed microsatellite markers to measure the genetic variability in breeding flocks (66 birds) from 3 farms in British Columbia. Significant allelic frequency differences were found between breeding flocks as well as between different ostrich subspecies. The Blue seems to be genetically closer to the Black than the Red. Heterozygosity was found to be comparable to that reported in other ostrich populations. Positive correlation (r = 0.28) was found between heterozygosity and body weight, however, there were no obvious signs of inbreeding depression. The results suggest breeding stocks of the three farms came from diverse sources. Calculated genetic distances confirmed the genetic relationship between the different subspecies. Among other paleognathous birds farmed today, emu (Dromaius novaehollandiae) farming is a growing industry in North America and the tinamou (Nothroprocta perdicaria sanbonii) is a newly farmed bird in British Columbia. The development of microsatellite markers for these two species will be useful for genomic studies. The cross-species amplification of microsatellites in these two species with the application of ten ostrich primer sets was examined. Five primer sets amplified emu D N A and four sets amplified tinamou DNA. Microsatellite marker LIST002 was found to be 68% conserved between the emu and the ostrich. For marker O SM 4 ostrich sequence was found to be conserved in both the tinamou and emu (68% and 79% respectively) in the stretch prior to the repeats region. O SM 1 was 50% conserved among the tinamou and the emu. One locus (LIST002) showed polymorphism in the tinamou. However, it is not known whether it contains a microsatellite. The results indicated that cross-species amplification of DNA using ostrich primers in the emu and tinamou can be obtained quite efficiently. However, obtaining microsatellites using cross species amplification is inferior to a species specific library. Albeit, microsatellite repeat were found and should be considered for use in future research.
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