Genetic Characterization of the Endangered Kiso Horse Using 31 Microsatellite DNAs

Abstract

ABSTRACT. In order to contribute to conservation of the endangered Kiso horse, we clarified their genetic information using 31 microsatellite DNAs, and genotyped 125 horses, 83% of the existing breed. First, we clarified the current status of the horses. The horses were confirmed to have experienced rapid loss of population causing a bottleneck, and their effective population size was much smaller than their census size. Moreover, the number of alleles (6.3), observed heterozygosity (0.674), and expected heterozygosity (0.662) were in the same range as other endangered horses all over the world. Therefore, although their inbreeding level was not so severe (F is : -0.017), the Kiso horse is surely one of the endangered. Second, we obtained genetic information of individuals. This information allowed us to understand the genetic distance of individuals, and might help in development of a reproductive strategy concerning the genetic distance between the mating pairs. Moreover, there appeared to be 4 subpopulations of Kiso horse, and this result was in good agreement with their historical background. Third, we confirmed that the parentage test for identification using the 31 microsatellite DNAs was highly reliable (probability of exclusion: 0.999999993). This identification increases the reliability of stud certification, and is also helpful for effective management. Understanding the genetic diversity within the population and the relationships among individuals is important to ensuring effective management for maintenance of genetic variation, and this study may help in conservation of the endangered Kiso horse.

Diversity and effective population size of four horse breeds from microsatellite DNA markers in South-Central Mexico

“…In general, the present results confirmed the usefulness of microsatellites in the assessment of genetic diversity and integrity of different horse breeds around the world (Aberle et al, 2004;Solis et al, 2005;Marletta et al, 2006;Luis et al, 2007;Burócziová andŘíha, 2009;Leroy et al, 2009;Chauhan et al, 2011;Ling et al, 2011;van de Goor et al, 2011;Conant et al, 2012;Prystupa et al, 2012;Khanshour et al, 2013;Berber et al, 2014). Genetic characterization helps to assure breed integrity and to assign individuals to defined populations (Glowatzki-Mullis et al, 2006).…”

“…In some genetic diversity studies with microsatellites the number of horses analysed per breed ranged from 17 to 24 (Aberle et al, 2004;Solis et al, 2005;Marletta et al, 2006;Burócziová andŘíha, 2009;Leroy et al, 2009;Chauhan et al, 2011;Ling et al, 2011;van de Goor et al, 2011;Prystupa et al, 2012;Khanshour et al, 2013;Berber et al, 2014), which is similar to the number of animals used per breed in the present study.…”

“…Heterozygosity was slightly higher than that reported for Thoroughbred horses (Cunningham, et al, 2001;GlowatzkiMullis, et al, 2006;van de Goor et al, 2011) and Quarter Horses (Luis et al, 2007) in previous studies with the same or similar loci and could be due in part to the random origin of the samples (different ranches). Similarly, lower heterozygosity values were reported in Argentine, Brazilian, Chilean and Venezuelan CRL horses (Cothran et al, 2011).…”

“…DNA concentration was measured with a NanoDrop 2000c spectrophotometer (Thermo Fisher Scientific v1.1.). Genotyping of samples was performed using the 17-microsatellite panel recommended by the International Society for Animal Genetics (ISAG) for identity and parentage testing (Table 1) (van de Goor et al, 2010). Polymerase chain reaction (PCR) conditions were optimized from the recommended StockMarks ® for Horses kit protocol (Applied Biosystems, Foster City, CA, USA).…”

“…Conservation of breed identity and adequate effective population size is pivotal for sound breeding management in any species, and genetic markers such as short tandem repeat (STR) loci (i.e. microsatellites) have been extensively used to examine genetic diversity and breed characterization in horse populations worldwide (Aberle et al, 2004;Marletta et al, 2006;Druml et al, 2007;Zuccaro et al, 2008;Felicetti et al, 2010;Chauhan et al, 2011;Ling et al, 2011;Takasu et al, 2012;Fornal et al, 2013;Berber et al, 2014). In this study, we used 17 microsatellite DNA markers to provide genetic diversity and effective population size of four horse breeds of economic and cultural importance in Mexico.…”