Survival of pigs with different characteristics of umbilical outpouching in a prospective cohort study of Danish pigs

Trine Hovmand-Hansen; Søren Saxmose Nielsen; Tina B Jensen; Kaj Vestergaard; Mai Britt F Nielsen; Henrik E Jensen

doi:10.1016/j.prevetmed.2021.105343

Survival of pigs with different characteristics of umbilical outpouching in a prospective cohort study of Danish pigs

Prev Vet Med. 2021 Apr 10:191:105343. doi: 10.1016/j.prevetmed.2021.105343. Online ahead of print.

Authors

Trine Hovmand-Hansen¹, Søren Saxmose Nielsen², Tina B Jensen³, Kaj Vestergaard³, Mai Britt F Nielsen³, Henrik E Jensen²

Affiliations

¹ Dept. of Veterinary and Animal Science, University of Copenhagen, Ridebanevej 3, 1870, Frederiksberg C, Denmark. Electronic address: trihov@sund.ku.dk.
² Dept. of Veterinary and Animal Science, University of Copenhagen, Ridebanevej 3, 1870, Frederiksberg C, Denmark.
³ Danish Agriculture and Food Council, SEGES, Axeltorv 3, 1609, Copenhagen, Denmark.

PMID: 33887619
DOI: 10.1016/j.prevetmed.2021.105343

Abstract

Umbilical hernia and other conditions clinically evident as umbilical outpouchings (UOs) affect the welfare and economy in Danish pig production. The objectives of the current study were to characterize the associations between 1) time of detection of the UOs and the odds of dying before scheduled slaughter; 2) time of death, irrespective of the cause, and clinical signs of the UOs, i.e. general condition, size, reducibility, form and skin-color of the UOs; and 3) occurrence of wounds on the UOs and clinical signs: general condition, size, reducibility, form and skin-color. A cohort of Danish conventional pigs with UOs (n = 255) were followed from the detection of an UO until spontaneous death, euthanization or slaughter of the pig. The pigs were clinically examined once a month, and when pigs with an UO died spontaneously, were euthanized or slaughtered, the causes and date of death were recorded. The effects of the clinical manifestations on overall survival were assessed using a Cox proportional hazards model. In total 57 % of the pigs died spontaneously or were euthanized before slaughter. The median age of spontaneous death or euthanasia was 85 days. The UOs were detected at different ages, with half of the pigs (52 %) detected in the farrowing section. No significant association was found between death before scheduled slaughter and the time of detection. Three different clinical manifestations were found to have a prognostic value for overall survival until slaughter, i.e. skin-color of the UO, a general condition of the pig and the size of the UO. An interaction was present between the size and the skin-color of the UO. Wounds on the UO were the most frequent complication resulting in euthanasia (37 %). The odds for developing a wound on the UO were higher for pigs in a general bad condition compared to pigs in a good condition (OR, 5.4; 95 % CL 2.5-11.3), and for pigs with an UO large in size compared to pigs with a small UO (OR, 4.8; 95 % CL 3.0-7.5). The identification of prognostic clinical signs in pigs with an UO is useful in the assessment and decision-making in relation to the future prospects of pigs with UOs.

Keywords: Fitness for transport; Pigs; Umbilical hernia; Umbilical outpouching; Welfare.