Erysipelothrix rhusiopathiae isolated from gull-inflicted wounds in southern right whale calves

Abstract

Southern right whales Eubalaena australis from Peninsula Valdés, Argentina, show wounds produced by kelp gulls Larus dominicanus that feed on the whales' dorsal skin and blubber. During the 2013 whale season, several calves were reported showing kelp gull injuries with a swollen area surrounded by rhomboid-shaped raised edges. Samples from 9 calves were taken in order to establish the etiology of these rhomboid-shaped wounds; 2 calves (one living, one dead) showed gull-inflicted injuries with rhomboid-shaped edges. Samples from the dead calf were histologically characterized by the presence of dermal congestion, suppurative dermatitis and panniculitis, necrotizing vasculitis and vascular thrombosis. Erysipelothrix rhusiopathiae was detected by culture and PCR in samples from both calves. In this study we report, for the first time to our knowledge, the isolation of E. rhusiopathiae from wounds produced by gull attacks on southern right whale calves, supplying evidence that these wounds may act as an entry route for pathogens. This work provides new information about the consequences of gull-inflicted injuries for whale health. KEY WORDS: Southern right whale · Eubalaena australis · Erysipelothrix rhusiopathiae · Skin injuries · Larus dominicanusResale or republication not permitted without written consent of the publisher

Cetacea

“…Two calves with wounds forming discrete rhomboid shapes have been described. Bacterial culture and PCR confirmed Erysipelothrix rhusiopathiae from lesions in these two calves (Fiorito et al, 2016). However, these were isolated cases and bacterial, viral or other infectious diseases that predispose the skin to predation have, to date, not been identified.…”

Gray Whale (Eschrichtius robustus) Health and Disease: Review and Future Directions

“…Rare observations of parasitic behavior of gulls feeding on live stranded neonate gray whales were made in the nursery lagoons (Eberhardt and Norris, 1964). Parasitic behavior of gulls on southern right whale calves (Eubalaena australis) has emerged as a significant health problem in Argentinian waters (Fiorito et al, 2016;McAloose et al, 2016).…”

Screening immune adjuvants for an inactivated vaccine against Erysipelothrix rhusiopathiae

“…rhusiopathiae is a Gram-positive rod-shaped nonsporeforming bacterium with a capsule but no flagellum (1), belonging to the genus Erysipelothrix in the family Erysipelothrichaceae. The bacterium is widely distributed in nature, causing diseases in a wide range of animals, including mammals, birds and fish (2)(3)(4)(5). Humans can be infected via trauma that results in skin lesions, thus acquiring erysipelas (6).…”