Premium
Plasma progesterone, oestradiol‐17β and total oestrogen profiles in relation to oestrous behaviour during induced ovulation in Murrah buffalo heifers
Author(s) -
Roy K. S.,
Prakash B. S.
Publication year - 2009
Publication title -
journal of animal physiology and animal nutrition
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.651
H-Index - 56
eISSN - 1439-0396
pISSN - 0931-2439
DOI - 10.1111/j.1439-0396.2008.00830.x
Subject(s) - estrous cycle , ovulation , endocrinology , medicine , murrah buffalo , uterus , prolactin , luteolysis , induced ovulation , hormone , biology , zoology
Summary The objectives of this study were to establish the characteristics of oestrous behaviour in Ovsynch (induction of ovulation through administration of GnRH‐PGF 2α ‐GnRH in a systemic manner on 0, seventh and ninth day respectively) and Ovsynch plus Norprolac (Quinagolide hydrochloride – an inhibitor of prolactin secretion) treated Murrah buffalo heifers and to determine the relationships between this behaviour and the plasma concentrations of oestradiol‐17β (E 2 ), total oestrogen, and progesterone. Oestrus was detected by visual observations of oestrus signs, per rectal examination of genitalia and bull parading thrice a day during treatment period. Among all the symptoms, it was observed that bull mounting of heifers in oestrus was highest. Examination of genital tracts per rectum revealed that the cervix was relaxed, uterus was turgid and ovaries had palpable follicle in animals with oestrus. The peak concentrations of E 2 (10.81 ± 0.62 pg/ml) and total oestrogen (17.11 ± 1.21 pg/ml) occurred at 9.45 ± 0.85 and 9.64 ± 0.93 h after second GnRH administration, respectively, in Ovsynch treated animals. However, the peak levels of E 2 (20.02 ± 2.87 pg/ml) and total oestrogen (32.71 ± 3.15 pg/ml) occurred at 10.18 ± 0.50 and 10.36 ± 0.75 h after second GnRH administration, respectively, in Ovsynch plus Norprolac treated animals. Plasma progesterone concentration was basal (0.20 ± 0.001 ng/ml) during the peri‐oestrus period. The plasma progesterone concentration was the lowest on the day of oestrus and increased to register a peak on day 13 ± 2 of the cycle. Oestrous behaviour was positively correlated with the peak concentration of E 2 (p < 0.001) and total oestrogen (p < 0.001) during the peri‐oestrus period. Inhibition of prolactin by Norprolac administration significantly increased the concentration of E 2 and total oestrogen during oestrus in buffaloes in comparison to those recorded in animals subjected to Ovsynch protocol alone. In conclusion, our results suggest that the peak concentrations of E 2 and total oestrogen and mean level of E 2 and total oestrogen during the peri‐oestrus period are the important factors contributing the behavioural manifestation of oestrus in buffalo cows.