Mycotic abortion in cattle

Abstract

Placentas and foetuses from 1107 bovine abortions were examined and a fungal infection was diagnosed in 131 instances. Fungi seen in silver impregnated sections of tissues could be placed into 3 categories designated aspergillus, phycomycete and atypical. Culture indicated that the first 2 of these categories were due to Aspergillus sp and Mortierella wolfii respectively. The infections in the atypical category are probably also due to Aspergillus sp. Gross or microscopic examination or culture of the placenta were valuable diagnostically but examination of the foetus was seldom of value as infection in most instances did not involve foetal tissues. Questionnaires indicated that many M. wolfii abortions were associated with the feeding of poorly prepared or stored grass silage. As the majority of cattle are fed hay or silage, no association could be demonstrated between Aspergillus sp abortion and these feeds. Fertility following fungal abortion was apparently unimpaired.

Fungi Associated with Bovine Abortion in the Northern Plains States (USA)

“…29 Another factor in bovine mycotic abortion monia were not seen in the 2 dams of the cases in this may be BVDV, which causes immunosuppression in survey or in the 3 dams of the more recent abortions. cattle by interfering with neutrophil function.…”

In utero infection of a calf by Saksenaea erythrospora resulting in neonatal abomasitis and dermatitis

“…8 Contamination of feed during winter months is often cited as a potential source of infection, and hematogenous spread from the rumen or respiratory tract to the placenta may result in necrotizing vasculitis and abortion. 7,9,16 Abortions often occur late in gestation, and premature birth of an affected calf may also occur as in the case presented herein. 2,7 Cutaneous lesions in the aborted fetus or neonatal calf, consisting of thick, elevated, hairless plaques around the eyes, shoulders, back, and sides, are often observed, along with occasional cases of bronchopneumonia.…”

“…8 Angiotropism is common, and lesions caused by these highly invasive fungi are typically associated with vasculitis. 6,8,9 In histopathologic sections, hyphae of mucoralean fungi often lack septa, unlike those of Aspergillus spp. 6,9 Otherwise, there is little to distinguish them from one another, making fungal culture often necessary.…”

“…6,8,9 In histopathologic sections, hyphae of mucoralean fungi often lack septa, unlike those of Aspergillus spp. 6,9 Otherwise, there is little to distinguish them from one another, making fungal culture often necessary. 6 The lack of prior published cases of Saksenaea infection as a cause of bovine neonatal death is likely due to the difficulty of inducing these fungi to sporulate for identification.…”

“…8 Typically, fungi can be recovered from the placenta, stomach contents, or skin lesions. 2,8,9 The most common mucoralean fungi identified include the following genera: Mucor, Absidia, Rhizopus, Rhizomucor, and Mortierella. 8 Angiotropism is common, and lesions caused by these highly invasive fungi are typically associated with vasculitis.…”