Early risk factors, development, disappearance and contents of umbilical outpouching in Danish pigs

The main objective of the study was to identify early risk factors associated with the development of umbilical outpouchings (UOs) in pigs. Secondly, to describe 1) the nature of UOs, 2) the age when UOs become visible, and 3) at which age UOs spontaneously may regress and disappear. A longitudinal study following pigs (n=3031) from birth to slaughter was carried out in two commercial Danish herds. In total, 8 % (n=255) of the pigs developed an UO between birth and death (spontaneous, euthanasia or slaughter). The odds for developing an UO was significantly lower for males than females (OR, 0.7; 95% CL, 0.50.9). Pigs born immature (OR, 3.4; 95% CL, 1.3-8.2) or observed with: 1) clinical sign of omphalitis (OR, 1.8; 95% CL, 1.1-2.8), 2) a elongated moist umbilical cord at birth (OR, 5.1; 95% CL, 2.6-9.8) or 3) a healed or healing protruding umbilicus in the second week after birth (OR, 1.9; 95% CL, 1.4-2.6) were associated with significant higher odds of developing an UO. No significant association (p-value >0.05) was found between the development of UOs and sow parity, litter size, birth weight and length of the umbilical cord. The nature of the UOs were mainly due to umbilical herniation and/or formation of abscesses or fibrosis. The majority of UOs became visible within the first 10 weeks of age (80%, n=234). Spontaneous regression of the UOs occurred in 14% (n=36) of the pigs; 83% (n=30) disappeared between the 4th and 14th week. Identifying piglets with high odds of developing UOs makes it possible to identify to which pig special attention should be paid during the daily management.