The length of gestation and parturition in 147 Arabian Thoroughbred mares were studied. Length of gestation averaged 330 days and was influenced by the age of mare. They were 335, 330 and 328 days for mares aged up to 4 years, 5 to 9 years and over 10 years, respectively. Parturition lasted 56 minutes on average and was not influenced by the reproductive condition of the mare. Most births occurred at night.
gestation; parturition; equine
