Distribution of serum melatonin concentration in pregnant Hungarian Fallow Donkey mares

Abstract

The serum melatonin concentration during gestation is a little studied area among livestock. The aim of this study was to focus on nocturnal serum melatonin concentration in connection to the reproductive cycle and gestation. The authors measured the blood serum melatonin concentration at different stages of gestation of nine pregnant Hungarian fallow donkey mares and nine non-pregnant controls at a nucleus farm located in Bőszénfa. Blood samples were taken from the jugular vein into blood tubes containing EDTA during nights. Animals were kept in closed dark stable and samplings were done with use of red light at <1 lux.