Predicting the onset of parturition during late gestation in
dairy cows using udder scoring and hormonal profiling
K.L. DAVIS AND K.L. MACMILLAN
Dexcel Limited, Private Bag 3221, Hamilton, New Zealand
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NZSAP 2002 Abstract No. 10
Proceedings of the New Zealand Society of Animal Production 62:
34-37
Sixty-four cows were blood sampled and physical signs of
impending parturition were scored daily from Day 272. Sampling and
scoring ceased on Day 282 of gestation or when parturition occurred,
whichever came about first. Mean udder development scores increased from
2.0 ± 0.76 (± SD) on Day -10 (ten days prior to
parturition) to 3.2 ± 0.72 (± SD) on Day 0 (day of
parturition) with 84% of cows having an udder score of 3 or 4 on the day
prior to parturition (Day -1). Teat distension, vulva swelling and
oedema were not useful as indicators of imminent parturition. Udder
score was the most useful predictor, but the low frequency of scores
less than 2 and greater than 3 on any one day resulted in unstable
models. Plasma samples were assayed for progesterone,
PGF2alpha metabolites (PGFM), cortisol and oestradiol.
Oestradiol concentration on Day 274 was a useful predictor of whether an
individual cow would calve within eight days (P=0.02). Plasma oestradiol
concentrations used to build models to predict whether a cow would calve
within the next five days were accurate from Day 272 to 275 of gestation
(P<0.05). Progesterone, PGFM and cortisol were unreliable indicators.
Keywords: NZSAPAB;
dairy; parturition; udder scoring; oestradiol
Last Updated 30/07/2002
