Pregnancy associated protein and progesterone concentrations during early pregnancy in Sirohi goats

Eight apparently healthy Sirohi goats, aged 2.5-3 years were synchronized and naturally served. Blood samples from each goat were collected every 4 days from day -4 (4 days before estrus) up to day 28 (day 28 after estrus) to determine progesterone and PAGs concentrations. Pregnancy diagnosis was done after one month using ultra-sonic scanning. The average serum progesterone concentration on day 4 before estrus and on the day of estrus was the lowest concentration recorded during the experiment. It increased non significantly on day 4 after estrus. Further it increased significantly (P < 0.05) on day 8 and remained almost similar upto day 12 of pregnancy. Later the progesterone concentration increased significantly (P < 0.01) from day 16 of pregnancy through day 28.The average serum PAG concentration on day 4 before estrus was the lowest concentration recorded during experiment. The serum PAG increased significantly (P < 0.05) on the day of estrus. Further it increased non significantly up to day 12 of pregnancy. Later the PAG concentration showed highly significant increase (P < 0.01) from day 16 of pregnancy through day 28 of pregnancy, respectively. The correlation between PAGs and progesterone concentration was significant and positive (r = 0.98; P < 0.05) from day 4 before estrus to 28th day of pregnancy in Sirohi goats. Although progesterone concentration is identified commercially as an aid to the diagnosis of pregnancy, similarly PAGs can also be an important alternate tool for accurate and early diagnosis of pregnancy by day 16 to day 20 in goats. (C) 2016 Elsevier B.V. All rights reserved.