Analysis of Genetic Diversity of Egyptian Pigeon Breeds

Genetic Structure of Racing Pigeons (Columba livia) Kept in Poland Based on Microsatellite Markers

Pigeons played a major role in communication before the invention of the telephone and the telegraph, as well as in wars, where they were used to carry information and orders over long distances. Currently, numerous sports competitions and races are held with their participation, and their breeding is demanding not only for breeders, but also for the birds themselves. Therefore, an analysis of the genetic structure of racing pigeons kept in Poland was undertaken on the basis of 16 microsatellite markers, as well as the evaluation of the microsatellite panel recommended by ISAG. For this purpose, Bayesian clustering, a dendrogram, and Principal Coordinate Analysis were conducted. In addition, statistical analysis was performed. Based on this research, it was observed that racing pigeons are genetically mixed, regardless of their place of origin. Moreover, genetic diversity was estimated at a relatively satisfactory level (Ho = 0.623, He = 0.684), and no alarmingly high inbreeding coefficient was observed (F = 0.088). Moreover, it was found that the panel recommended by ISAG can be successfully used in Poland for individual identification and parentage testing (PIC = 0.639, CE-1P = 0.9987233, CE-2P = 0.9999872, CE-PP = 0.99999999).

LDHA gene is associated with pigeon survivability during racing competitions

Pigeon racing is a popular sport worldwide. Pigeons are under continuous selection to improve speed, spatial orientation, and endurance during long flights. However, numerous genetic and non-genetic factors affect survivability and homing ability, making such traits difficult for breeders to control. Polymorphisms in the lactate dehydrogenase A gene (LDHA) likely affects pigeon racing and homing abilities, due to its role in physical and mental performance. Additionally, the adenylate cyclase activating polypeptide 1 gene (ADCYAP1) has been associated with physiological and behavioral shifts that occur during avian migration. In this study, we examined the association between LDHA and ADCYAP1 genotypes with pigeon survivability during racing competitions. Survivability was evaluated through the estimated breeding value (EBV) of each individual's total race distances during its athletic life. ADCYAP1 was not polymorphic among our samples, while LDHA genotypes were significantly associated with deviated EBV values of longer total race distance; individuals carrying the S+ genotype had higher EBV (i.e., greater survivability). Thus, the LDHA locus might be useful for marker-assisted selection, empowering breeders and trainers to maximize pigeon quality. Moreover, data obtained from breeding will also improve our understanding of the genetic mechanism underlying navigation and flight for wild migrating bird species.

Genetic characterization of 11 microsatellite loci in Egyptian pigeons (Columba livia domestica) and their cross-species amplification in other Columbidae populations

Aim

This study aimed to analyze the genetic diversity and relationships of 10 Egyptian pigeon populations belonging to Columba livia domestica speciesusing 11 microsatellite markers and to investigate the success of these markers amplification across another eight pigeon species.

Methods

Genomic DNA was isolated from feather samples of179 pigeon samples from 10 Egyptian breeds: Asfer Weraq (n=14), Austoraly (n=20), Reehani (n=21), Messawed (n=17), Nemssawy (n=27), Otatti (n=12), Morasla (n=17), Tumbler (n=22), Halaby Asfer (n=10), and Karakandy (n=19) in addition to Japanese feral pigeons (n=30). Genotyping was done using 11 specific polymorphic microsatellite makers. Moreover, 37 samples not belonging to C. livia domestica but belonging to another eight pigeon species were genotyped. The polymerase chain reaction (PCR) products were electrophoresed on an ABI 3130xl DNA Sequencer. The basic measures of genetic diversity and phylogenetic trees were computed using bioinformatics software.

Results

Across the 10 studied Egyptian populations, the number of alleles per locus ranged from 3 to 19 and the average number of alleles observed was 9.091. The lowest value of expected heterozygosity (0.373) was obtained for the Reehani breed, and the highest value (0.706) was found for Morasla breed. The overall expected heterozygosity of Egyptian pigeons was 0.548. The F_ST coefficient which indicates fixation coefficients of subpopulations within the total population for the 11 loci varied from 0.318 to 0.114 with a relatively high mean (0.226). In our study, the F_IS showed a relatively high average(0.037). The pairwise Reynolds's genetic distance between the11 studied pigeon populations recorded lower values between Otatti and Austoraly (0.025) and between Morasla and Japanese feral pigeons (0.054). These results are supported by clustering pattern either by the neighbor-joining phylogenetic tree or by a Bayesian clustering of STRUCTURE with the admixture method.

Conclusions

We confirm the applicability of the CliµD17, CliµT17, CliµD16, CliµD32, CliµT13, CliµD01, PG1, PG2, PG4, PG6, and PG7 microsatellite markers among Egyptian domestic pigeons and across other pigeon species using cross-species amplification method. The information from this study should be useful for genetic characterization and for developing conservation programs of this important species.