Sows occasionally show oestrous behaviour within 5 days of farrowing: this is termed post-partum oestrus (PPO). This study investigated the incidence and possible causes of PPO on nine Dutch farms. Lactation records (n = 1374) were used, hack fat thickness was measured (n=25), and ovarian condition was assessed by transrectal ultrasonography. The incidence of PPO ranged from 0% to 62% on the different farms. On average, PPO started 59 hours after farrowing and lasted for 55 hours. Sows with PPO were younger than sows without PPO (parity 3.8 ± 0.2 v.v 4.4 ± 0.1, respectively; P <0.05) and had more back fat than sows without PPO (21.3 ± 1.2 vs 17.9 ± 1.2 mm, respectively: P <0.10). Occasionally, some follicle growth was observed in sows with PPO, but ovulation did not occur. PPO did not affect the weaning-to-mating interval or piglet mortality during lactation.
|Number of pages||6|
|Journal||Tijdschrift voor Diergeneeskunde|
|Publication status||Published - 2005|
- pig farming
- animal behaviour
- abnormal behaviour