The Thai Journal of Veterinary Medicine
Article Title
Abstract
The aim of the present study was to investigate the effects of the weaning-to-oestrus interval (WOI) and parity on the expression of oestrus and the timing of ovulation in crossbred (Large White x Landrace) sows. The detection of pro-oestrus and oestrus was performed every 8 hrs in all sows, by observing the reddening and swelling of the vulva and by applying the back pressure test in the presence of a boar. Ovulation was monitored every 8 hrs using transrectal ultrasonography. The duration of oestrus was 59.1, 59.8 and 65.3 hrs for parities 1, 2 and 3-4, respectively. Parity 1 and 2 sows had a significantly shorter oestrus duration compared with parities 3-4 (p<0.01 and p<0.05, respectively). No difference in the pro-oestrus duration and ovulation times were found among parity 1, 2 and 3-4 sows. No difference in the pro-oestrus duration was found among sows with a WOI of 1-3, 4 and 5-7 days. Oestrus duration from the onset of standing oestrus to ovulation was 67.4, 58.5, 58.2 hrs and 48.6, 41.5, 40.2 hrs for sows with a WOI of 1-3, 4 and 5-7 days. Sows with a WOI of 1-3 days had a significantly longer oestrus duration and a longer ovulation time than sows with a WOI 4 and 5-7 days (p<0.001 and p<0.05, respectively). A significant negative correlation between the WOI and oestrus duration (r=-0.30, p<0.001) and between the WOI and ovulation time (r=-0.33, p<0.001) was observed. Oestrus duration was positively correlated with the ovulation time (r=0.82, p<0.001), but was negatively correlated with the relative ovulation time (r=-0.23, p<0.01). It was possible to use the WOI and the oestrus duration to predict the ovulation time.
Publisher
Faculty of Veterinary Science, Chulalongkorn University
First Page
55
Last Page
62
Recommended Citation
Urasopon, Nontakorn; Tantasuparuk, Wichai; and Techakumphu, Mongkol
(2003)
"THE EFFECTS OF WEANING-TO-OESTRUS INTERVAL ON THE EXPRESSION OF OESTRUS AND THE TIMING OF OVULATION IN SOWS,"
The Thai Journal of Veterinary Medicine: Vol. 33:
Iss.
2, Article 8.
Available at:
https://digital.car.chula.ac.th/tjvm/vol33/iss2/8