Fatal Rectal Perforation Following Boar-to-Boar Mounting

Abstract

Although abnormal sexual behavior, including boar-to-boar mounting with anal penetration, is recognized in pubescent pigs, reports of the pathologic consequences are scarce. A 7-month-old male minipig, housed with age-matched males, died within 1 day of the onset of lethargy and reluctance to rise. At necropsy, 2 rectal tears were identified as the cause for fibrinous peritonitis, and spermatozoa were identified in the pelvic and peritoneal cavity by light and transmission electron microscopy. According to DNA typing results, using 11 porcine microsatellites, the intraperitoneal semen was from at least 2 pen mates. The prohibition of castration of fattening pigs, implemented or planned in multiple European countries, could increase the risk of rectal perforation in co-housed pigs.

Male grey seal commits fatal sexual interaction with adult female harbour seals in the German Wadden Sea

“…Along the coastline of Dithmarschen, there are several sandbanks close to the shore, where harbour seals haul out routinely and grey seals are known to visit these occasionally. Seals are generally polygamous and depending on the group size, the sex ratio and the social system, different aggressive mating strategies can develop 53,[56][57][58][59] . Injuries during interspecific interactions become more likely if there is great disparity in size and weight 52 .…”

“…Most reports of mating-related trauma in pinnipeds refer to external, dorsal head and neck wounds of females after being bitten, pinned down or dragged by males 13 , 55 – 57 . Whereas likewise observations for aggressive mating behaviour and external lesions exist for many other vertebrate classes, evidence of internal injuries remains scarce 55 , 58 . A well-documented case was reported in several male southern sea otters ( Enhydra lutris nereis ) force-copulating with juvenile Pacific harbour seals ( Phoca vitulina richardsi ) 53 .…”