MVSc

With the objective of studying the occurrence, onset, duration and
intensity of metoestrual bleeding and its effect on fertility in natural and induced
oestrus in cattle, detailed data of animals belonging to University Livestock Farm
and those presented at Artificial Insemination Centre and Bull Station, attached to
the Department of Animal Reproduction, College of Veterinary and Animal
Sciences, Mannuthy, were collected using a suitable proforma. Animals with the
history of metoestrual bleeding were randomly selected and allotted to the
following groups. Group I consisted of 16 animals, comprising- of eight cows and
eight heifers, with the history of metoestrual bleeding that were inseminated at
natural oestrus. Sixteen animals in group II (eight cows and eight heifers) with the
history of metoestrual bleeding were subjected to induction of oestrus on tenth
day using 25 mg PGF2 alpha (Lutalyse), which were inseminated at 72 and 96 h
after the administration of Lutalyse. Sixteen animals (eight cows and eight
heifers) which did not show metoestrual bleeding formed the group Ill.
Out of 1626 animals screened, 99 (6.09 per cent) animals exhibited signs
of metoestrual bleeding in one or more oestrous cycles. The occurrence was found
to be higher in heifers (9.87 per cent) than in cows (4.52 per cent). Higher
percentage of Brown Swiss cross bred cattle (9.88 per cent) exhibited signs of
metoestrual bleeding, followed by Holstein-Friesian cross bred (7.66 per cent) and
Jersey cross breds (7.4 7 per cent).
Out of 99 animals with metoestrual bleeding, eight (8.08 per cent) animals
showed bleeding on the day of oestrus (day 0), 44 (44.44 per cent) on day 1 of
oestrus, 26 (26.26 per cent) on day 2 of oestrus and 21 (21.21) on day 3 of oestrus.
Duration of metoestrual bleeding ranged from 6-36 h with a mean of 13.38
± 2.64 h. Thirteen (13.13 per cent), 57 (57.58 per cent) and 29 (29.30 per cent)
animals exhibited scanty, moderate and profuse bleeding, respectively.

Thick mucus blood tinged discharge was observed in 60 per cent of cases,
which on microscopic examination revealed fern pattern, that lay scattered in
disintegrated form with presence of RBCs, in stained smears. Thin mucus blood
tinged discharge was noticed in 40 per cent of cases with presence of RBCs in
stained smears, without fern pattern.
Microbial growth was not detected when metoestrual discharge was
inoculated on the culture media and incubated at 37°C for 24 h. Gram positive
bacilli were detected as the contaminants after 48 h.
Out of eight cows and eight heifers in group II subjected to PGF2alpha
administration, seven (87.5 per cent) and eight (100 per cent) responded to
treatment, respectively. The overall oestrus response was 93.75 per cent. The time
taken for the induction of oestrus in cows was 66.14 ± 1.55 h as against 59.88 ±
1.66 h in group II heifers. Average duration of oestrus in cows and heifers was
25.13 ± 0.99 and 18.75 ± 0.53; 31.43 ± 1.13 and 28.75 ± 2.00, and 23.63 ± 2.27
and 19.38 ± 0.65 h for groups I, 11 and III, respectively. Analysis of data revealed
significant difference in the duration of oestrus in cows and heifers in group II
from that of cows and heifers in groups I and III (P 37.5 per cent of cows and 12.5,37.5 and 50 per cent heifers showed high, medium
and low intensity of oestrus, respectively. In group II the corresponding values
were 57.14, 28.57 and 14.28 per cent in cows and 62.5, 25 and 12.5 per cent in
heifers. In group III 12.5, 37.5 and 50 per cent cows and 25, 37.5 and 37.5 per
cent heifers exhibited high, medium and low intensity of oestrus, respectively. Out
.
of eight cows and eight heifers induced, none exhibited metoestrual bleeding in
the induced heat.
The overall conception rate in groups I, Il and III were 18.75, 66.66 and
43.75 per cent, respectively. It can be recommended that induction of oestrus
using prostaglandin can be employed for enhancing the conception rate in animals
with the history of met oestrual bleeding.