MANAGEMENT OF OESTROUS CYCLE IN CROSSBRED CATTLE USING PROSTAGLANDIN
Loading...
Date
1994
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
COLLEGE OF VETERINARY AND ANIMAL SCIENCE,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,
v/ere allotted to three different groups. Sixteen heifers and
16 cows in group I v/ere given 25 mg PGF2 alpha (Lutalyse)
intramuscularly v;hen they had functional corpora lutea, v/hile
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).
Tv/elve heifers (75%) and 16 cows (100%) in group I and
all animals in group II responded to treatment. Mean tim.e
taken for induction of oestrus was 56.64 and 65.44 h
respectively in heifers and cov;s. 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 v/as
observed among cows between experimental and control groups.
All experimental animals v/hich 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 shov/ed 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 group
I recorded 25 and 62.50 per cent and 37.50 and 62.50 per cent
first insemination and overall conception rates respectively
when inseminated 72 h and 96 h posttreatment. When heifers
and cov/s in group II were inseminated 72 h 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 v;as no influence of parity
or season on the conception rate. Similarly the time taken
for induction of oestrus, duration 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
Keywords
null
Citation
KVASU REFERENCE STYLE