Srivastava SK, Sanwal PC, Umashankar U, Varshney VP, Sahni KL. Pregnancy rates in bovines based on plasma progesterone concentration during AI under farm and village conditions. Indian J of Anim Sci. 2012;69(6). Accessed October 23, 2025. https://epubs.icar.org.in/index.php/IJAnS/article/view/20597