| dc.description.abstract | A total number of fifty-three (53) dairy cows were used i) to detect the causes of repeat
breeding syndrome of dairy cows in a farm, ii) to evaluate the responses of
gonadotrophin releasing hormone and prostaglandin for management of repeat breeding
syndrome and iii) to evaluate the conception rate in hormonally treated cows after
inseminated naturally and artificially. All experimental animals were treated with three
protocols: Select synch protocol, Ovusynch protocol and PGF2α plus PGF2α injection
selected on the basis of findings of rectal palpation. The estrus cows were inseminated
naturally or artificially. Pregnancy was confirmed by non-return to estrus and rectal
palpation. Among all the cows, 54.72 % cows had cystic ovarian degeneration diagnosed
by rectal palpation. The estrous response rate in Select synch, Ovusynch, andPGF2α plus
PGF2α protocols were 100%, 100% and 89.47%, respectively. The mean time of onset of
estrous was 49 ± 3.41 hr. in Select synch, 48.6 ± 2.98 hr. in Ovusynch and 44.26 ± 15.8
hr. in PGF2α plus PGF2α protocol, respectively. There was no significant difference
(P>0.05) among the groups of dairy cows on the time of onset of estrous. The mean time
of duration of estrous in Select synch, Ovusynch, and PGF2α plus PGF2α protocols were
40.1 ± 3.85 hr., 47.1 ± 5.61 hr. and 37.5 ± 13.44 hr., respectively. There was no
significant difference (P>0.05) among the groups on both onset of estrous and duration
of estrous. Poor conception rates following induction of estrus by Select synch,
Ovusynch and PGF2α plus PGF2α protocol in dairy cows inseminated artificially were
found, whereas the conception rate following induction of estrous by three protocols in
naturally inseminated dairy cows was 100%. The overall conception rate of in cows
(n=26) inseminated naturally was 100% and artificially (n=25) were only 8%. There was
significant (P<0.05) difference on conception rate of dairy cows between artificial
insemination and natural service groups. Though the estrus responses to hormonal
treatment were better, however, conception rate was significantly lower by artificial
insemination than natural. It is suggested that it is better to ensure the semen quality and
AI technician skillness before insemination at Small and large scale dairy farms. | en_US |
