Microflora Associated With the Skin of the Bowhead Whale (Balaena Mysticetus)

Abstract

A study of the microbiological flora isolated from cultures of normal and lesional skin tissue samples collected from 19 bowhead whales (Balaena mysticetus) over a 4 yr period is presented. These cultures were obtained from 30 tissue samples (17 normal, 13 lesion) and 248 swab samples (157 normal, 91 lesion). Seven hundred-thirty bacterial and yeast isolations were made (285 normal, 445 lesion). Distribution revealed that 56% of the gram positive bacterial isolates, 75% of the gram negative bacterial isolates and 64% of the yeast isolates recovered were associated with lesional skin. It was found that 80% of one group of Corynebacterium sp. isolates, 90% of the Acinetobacter sp. isolates and 94% of the Moraxella sp. isolates were associated with lesional skin. Although the primary yeasts recovered were Candida spp., they were found on both normal and lesional skin. Enzymatic assays of isolates from normal and lesional skin demonstrated production of enzymes capable of causing necrosis. The majority of the microorganisms recovered were facultative anaerobes and many of them could be considered potential pathogens of mammalian hosts.

Yeast Infection in a Beached Southern Right Whale (Eubalaena Australis) Neonate

“…The study by Schotts et al (1990) found that Candida species were the dominant yeasts found on bowhead whales subjected to oil pollution and that these yeast species were found on both normal, as well as lesional skin. Species isolated and identified included Candida krusei, C. parapsilosis, C. rugosa, C. humicola, C. intermedia, C. guilliermondii, C. viswanathii, C. lipolytica, C. stellatoidea, and C. utilis.…”

“…The results of a 4-yr year study of bowhead whales (Balaena mysticetus) near Barrow, Alaska that were exposed to petrochemical industrial activities, were presented in 1990 (Schotts et al, 1990). These whales were characterized by dozens of roughened areas on their skin surface.…”

“…Swabs from the lesions, as well as nonlesioned skin, were cultivated, and 80 species bacteria and yeasts were isolated and identified. The dominant yeast species belonged to the genera Candida, Cryptococcus, and Rhodotorula and it was pointed out that these taxa have the ability to degrade hydrocarbons (Schotts et al, 1990).…”

Cutaneous Lesions in Cetaceans: An Indicator of Ecosystem Status?

“…A study conducted over a four year period found that a range of microbes were associated with lesional and non-lesional skin in a group of bowhead whales (Balaena mysticetus), characterized by dozens to hundreds of roughened areas on their skin surfaces [28]. The majority of microbes, isolated during the study, were associated with the lesional skin: 56% of Gram positive bacteria, 75% of Gram negative bacteria and 64% of the yeasts.…”

“…Subsequent tests on the isolates showed the production of enzymes able to cause necrosis by microbes originating from both lesional and non-lesional skin. These whales occurred in regions with increased industrial activities (gas and oil exploration) in the Beaufort Sea; the authors speculated that the roughened skin areas might have been associated with the adherence of spilled oil [28].…”