Vale W G, Melo P C H, Walter E, Ribeiro H F L, Rolim-Filho S T, Reis A N, Sousa J S and Silva A O A 2011: Fixed timed artificial insemination (FTAI) through the progesterone (CIDR) of 1^st, 2^nd, 3^rd and 4^th uses in bovine. I. Conception rate related to reproductive category, related to body condition scoring (BCS), related to calf withdrawal and use of eCG. Livestock Research for Rural Development. Volume 23, Article #205. Retrieved , from http://www.lrrd.org/lrrd23/10/vale23205.htm