Genetic study of gestation length in andalusian and arabian mares

Gestational length in Carthusian broodmares: effects of breeding season, foal gender, age of mare, year of parturition, parity and sire

“…This fact could lead to an early end of pregnancy as a mechanism for adjusting to the adverse climatic and nutritional conditions (Pérez et al 2003). However, we did not find any significant difference in GLs in the Carthusian broodmares studied between 1998 and 2005, despite the differences in climate, results which disagree with those presented previously by Valera et al (2006). One plausible explanation could be the feed supplementation when the environmental conditions were not adequate for the mares.…”

“…Average values obtained in Carthusian mares were shorter than those obtained in different breeds such as, Thoroughbreds (Hintz et al 1992, Davies-Morel et al 2002, Kurtz Filho et al 1997, Duggan et al 2008, Sharma and Dhaliwal 2010, Freibergers (Giger et al 1997), Lipizzaners (Heidler et al 2004), Quarter Horses (Pool-Anderson et al 1994, Guay et al 2002, Duggan et al 2008), Hannoverians (Winter et al 2007), Pantaneira (Zúccari et al 2002), Andalusians (Valera et al 2006) and Arabians mares (Valera et al 2006, Cilek 2009). …”

“…Dry years with high average temperatures have a negative effect on GL. In this way, Valera et al (2006) stated that dry years or those with more extreme temperatures are the years with GLs longer than expected. The main reason could be the influence of the nutritional quality of feedstuffs.…”

“…Hence, favorable weather conditions affect the nutritional value of grasslands and, as a result, the mare might have a better nutritional intake and the foal would require less time to achieve the proper weight for birth. Valera et al (2006) noted that the mating period accounts for 4.4% of the variance in the GL of Andalusian and Arabian broodmares in the south of Spain. In our opinion, the differences between the above mentioned investigations could be partially explained according to the different climatic conditions over the years and/or the country.…”

“…Up to now, GL data have been reported for Thoroughbreds (Hintz et alElliot et al 2009, Sharma andDhaliwal 2010), Freibergers (Giger et al 1997), Lipizzaners (Heidler et al 2004), Friesians (Sevinga et al 2004), Quarter Horses (Guay et al 2002, Duggan et al 2008, Standardbreds (Marteniuk et al 1998, Villani andRomano 2008), Criollo (Winter et al 2007), Pantaneira (Zúccari et al 2002), Andalusians (Valera et al 2006), Arabians (Demirci 1988, El-Wishi et al 1990, Valera et al 2006, Cilek 2009, Meliani et al 2011) and Andalusians of Carthusian strain (Pérez et al 2003). In all these studies, GL ranges between 330 and 350 days.…”