USMAN T, SUHAIL SM, ZHANG X, GUO G, ULLAH I, SADIQUE U, et al. Effects of non-genetic factors on age at first conception and calving interval in Holstein cattle under subtropical conditions. Indian J of Anim Sci [Internet]. 2014 Jan. 30 [cited 2026 Oct. 23];84(1):45–49. Available from: http://epubs.icar.org.in/index.php/IJAnS/article/view/37306