Biomedical Engineering Reference
In-Depth Information
Table 1
Signs of oestrus in buffaloes during different seasons
Symptoms
Medium monsoon
Peak winter
Low summer
Bellowing
−
+
−
Mucus discharge
+
+
+/−
Swollen vulva
+/−
+
−
Activity
+
+
+
Frequent urination
+
+
+
Uterine tone
+
+
+
Open cervix
+
+
+
Nature of cervical
Periodic thick
Frequent thin
Patchy thick
Discharge
Yellowish
Glassy copius
Opaque very less
Source: Modi fi ed from Janakiraman (
1978
)
+
present, − absent, +/− present in some cases only
located ipsilateral to the gravid horn (Baruselli
et al.
1997
). As in cattle, follicular growth occurs
in waves in buffaloes, and twin ovulations are
rarely observed. Two-wave cycles in buffalo are
common (63.3%) followed by three-wave cycles
(33.3%) and a single wave cycle (3.3%). The
number of waves influences the length of the
luteal phase and the oestrous cycle.
The oestrus cycle of buffalo varies in different
breeds. The total duration of oestrus is usually
24 h but varies from 12 to 72 h. The most reliable
sign of oestrus in buffaloes is frequent urination.
The behavioural signs of oestrus are much less
pronounced in buffalo than in cattle (Table
1
).
Many buffaloes show oestrus only at night time
and for short period. A lactating buffalo may
slightly decrease in milk yield on the day of heat.
The buffalo in heat may be more restless and
difficult to milk (Bhikane and Kawitkar
2000
) .
Age at puberty: 36-42 months
or together, include age of puberty or maturity,
pattern of oestrus cycle and oestrus behaviour,
length of breeding, ovulation rate, lactational
anoestrus period, postpartum anoestrus, inter-
calving period and reproductive life span. A com-
bination of these traits is used to measure breeding
efficiency or breeding performance in farm ani-
mals (Agarwal
2003
) . Reproductive ef fi ci ency
in buffalo is reported to be alarmingly low,
causing severe economic losses to milk produc-
ers. However, the reproductive efficiency of some
buffaloes reared under farm conditions is better.
In Northern India, conception rate is highest
during the cool season (October to January) and
lowest during the hot-dry season (May to July).
In Southern India, the period from October
to April is more favourable for conception in
buffaloes. Maximum conception rates have
been observed during winter in buffaloes (Rao
et al.
1973
; Rao and Kodagali
1983
) . GnRH
analogue improves the conception rate in repeat
breeder Nili-Ravi buffaloes when administered
as a single dose at the time of insemination
(Ahmad et al.
2002
) .
Studies have established a negative influence
of ambient temperature and duration of sunshine
on incidence of oestrus, and ambient humidity
has a favourable effect. The period of the year
from October-March with moderate RH and low
ambient temperature is most congenial for
resumption of postpartum oestrus. However, high
humidity (hot-humid season) coupled with
moderate temperature has a negative effect on
postpartum oestrus (Reddy
1985
) . It has been
observed that a maximum % (75.02%) of open
•
•
Length of oestrus cycle: 20 ± 2 days
•
Duration of heat: 12-24 h
•
Time of ovulation: 10-14 h after end of oestrus
•
Period of maximum fertility: last 8 h of oestrus
•
Gestation period: 310 days
•
Period of involution of uterus: 25-35 days
9.5
Reproductive Performance
in Buffalo
The reproductive efficiency in buffaloes is deter-
mined by many different processes, which result
from interaction among genetic and environmen-
tal factors. The processes involved, individually
