Management of Oestrous Cycle in Crossbred Cattle Using Prostaglandin
Loading...
Files
Date
1994
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Department of Animal Reproduction, College of Veterinary and Animal Sciences,Mannuthy
Abstract
With the object of studying the efficacy of administration of prostaglandin F2 alpha in the management of oestrous cycle and fertility of fixed time insemination in induced oestrus, 96 heifers and cows which were cycling, selected from Kerala Agricultural University Livestock Farms, were allotted to three different groups. Sixteen heifers and 16 cows in group I were given 25 mg PGF2 alpha (Lutalyse) intramuscularly when they had functional corpora lutea, while in group II, 16 heifers and 16 cows were administered two injections of PGF2 alpha 25 mg each 13 days apart. Sixteen heifers and 16 cows were treated as control (Group III).
Twelve heifers (75%) and 16 cows (100%) in group I and all animals in group II responded to treatment. Mean time taken for induction of oestrus was 56.64 and 65.44 h respectively in heifers and cows. This difference was statistically significant. Parity of cows significantly influenced the time taken for induction of oestrus. Duration of oestrus was significantly different between heifers
(21.86 h) and cows (31.13h) of the experimental group. Significant difference in the duration of oestrus was observed among cows between experimental and control groups. All experimental animals which responded to PGF2 alpha showed marginal increase in physical characters of the reproductive tract like vulval oedema, hyperaemia of vaginal mucosa, vulval discharge and tonicity of uterine horns. Majority of the experimental animals showed medium to high intensity of oestrus compared to natural oestrus.
The first insemination and overall conception rates of heifers in group I, inseminated 72 h post-treatment, were 33.33 and 66.67 per cent respectively as against 33.33 and 50 per cent when inseminated 96 h post-treatment. Cows in groupI recorded 25 and 62.50 per cent and 37.50 and 62. 50per cent first insemination and overall conception rates respectively when inseminated 72 h and 96 h post-treatment. When heifers and cows in group II were inseminated 72h after the administration of the second dose of PGF2 alpha, 12.50 and 25 per cent conceived at first insemination with overall conception rate of 62.50 and 37.50 per cent respectively. The corresponding values in group II, when inseminated 96 h, were 25 and 12.5 per cent and 50 and 12.5 per cent
respectively. Among control 6.25 per cent of heifers and 18.75 per cent of cows conceived at first insemination. The first insemination conception rate of heifers of experimental (25%) and control groups (6.25%) were significantly different. However, overall conception rate did not differ between the three groups. There was no influence of parity or season on the conception rate. Similarly the time taken for induction of oestrus, duratioh of oestrus, physical changes of the reproductive tract during oestrus and intensity of oestrus did not affect the conception rate. Heifers and cows required 1.88 and 1.93 inseminations respectively per conception when treated with PGF2 alpha as against 3.14 and 3.33 in the control group. Though, the present investigation revealed that PGF2 alpha can be used in the management of oestrous cycle in crossbred heifers and cows with fixed time insemination, the high cost of the drug and the conception rate obtained warrant further studies on fertility in relation to detected oestrus and fixed time insemination after the administration of PGF2 alpha.
Description
P G
Keywords
Citation
170674