Correspondence between hormone levels in blood and feces or urine in pregnant cattle

Abstract

Pregnancy diagnosis is a key to the effective reproductive management of animals. Although transrectal palpation has been established as a convenient method to diagnose pregnancy, the measurements of the levels of reproductive hormone have yet to be established. For this, a study was performed to compare the levels of the reproductive hormone in blood with those of matching urine and fecal samples. A total of 30 pregnant cows (10 in each pregnancy trimester) were selected from 226 pregnant cattle based on age, body condition score (BCS), and parity. The reproductive hormones were assayed in blood and corresponding urine and fecal samples through commercial kits by Enzyme Linked Immuno Sorbent Assay (ELISA). A significant variation (p<0.05) in progesterone (P4) and Estradiol (Ez) concentration among trimesters was found in serum, as well as in urine and feces. The values for Luteinizing Hormone (LH) varied less among the trimesters in all types of samples. Follicle Stimulating Hormone (FSH) levels varied significantly (p <0.05) in serum and fecal samples. A moderate positive (r=0.44) relationship was observed between serum vs urine FSH in the 1st trimester. On the contrary, a moderate positive relationship was found between serum vs urine p4 (r=0.40) and serum vs urine FSH in the 2nd-4th trimester, and a strong relationship (r=0.54) was found in serum vs fecal FSH, which implies that urine and feces could be used for reproductive hormone assays.