Seasonal effects on the efficacy of intravaginal CIDR devices
for oestrous synchronization of farmed fallow deer (Dama dama)
C.J. Morrow, G.W. Asher, J.F. Smith, H.N. Jabbour, R.C. Mulley,
L.M. McLeay
Reproduction Group, Ruakura Agricultural Centre, AgResearch,
Private Bag 3123, Hamilton, New Zealand
Proceedings of the New Zealand Society of Animal Production.
1992, 52: 165-170
Eighty mature fallow deer does were allocated to four treatment
groups (n+20) for which oestrous synchronization treatment consisted of
intravaginal insertion of single CIDR devices for 14 days and
prostaglandin administration on days 0 and 10 of device insertion.
Treatment groups were staggered successively by 7-day intervals from
early March to late May, the period spanning the natural mating season
(rut). Observations to determine the onset of oestrus were performed
24-72 hours after CIDR device withdrawal and blood samples were
collected four times during insertion and then every 2 days, for 14
days, from CIDR device withdrawal. Plasma samples were analysed for
progesterone concentration to determine luteal development. A group of
untreated contemporary control does were allowed to mate naturally to
crayon-harnessed bucks to determine the period of the 1990 natural rut.
Oestrus and ovulation were detected on 69% and 80% of occasions
respectively following CIDR device withdrawal, with ovulation following
oestrus on 98% of occasions. Ovulation not preceded by observed
oestrus, probably representing silent ovulations, occurred early in the
breeding season. There was complete failure of response, in terms of
does exhibiting oestrus increased from 0-10% to 89-100% with the
greatest coinciding with the onset of the natural rut. In addition, the
mean interval from CIDR device withdrawal to onset of oestrus tended to
decrease from between 71-88h to 47-63h and oestrous synchrony improved
progressively during the trial. The efficacy of CIDR devices in
synchronizing oestrus and ovulation in fallow deer does is clearly
influenced by timing of treatment relative to the natural breeding
season of the herd.
Keywords: NZSAPAB;
Fallow deer; Dama dama; oestrous synchronization; CIDR
devices
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Last Updated 25-01-1997
