title: [Post-partum oestrous behaviour in sows is not associated with ovulation].
abstract: 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, backfat 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 vs 4.4 +/- 0.1, respectively; P < 0. 05) and had more backfat 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.
authors.affiliation: Departement Dierwetenschappen, Wageningen Universiteit.
authors.forename: N Y P
authors.initials: NY
authors.lastname: Souren
authors.forename: P
authors.initials: P
authors.lastname: Langendijk
authors.forename: N M
authors.initials: NM
authors.lastname: Soede
mesh_terms: D000273:Adipose Tissue / Q000378:metabolism; D000367:Age Factors; D000818:Animals; D004971:Estrus / Q000502:physiology*; D005260:Female; D007774:Lactation / Q000502:physiology*; D010060:Ovulation / Q000502:physiology*; D010298:Parity; D049590:Postpartum Period; D012307:Risk Factors; D013552:Swine / Q000502:physiology*