Abstract-Artificial pond microcosms with pond water, including phytoplankton, periphyton, macrophytes, and larval gray tree frogs (Hyla versicolor), were treated with atrazine to achieve final aqueous concentrations of 0, 20, 200, or 2,000 g/L. Dissolved oxygen concentrations (DO) decreased to approx. 20 to 40% of their preexposure values in the 200-and 2,000-g/L treatment groups within 1 d of atrazine addition. Dissolved oxygen in these microcosms returned to control concentrations by 10 d after exposure but declined again to approximately 60 to 80% of control values at 21 d after exposure and remained depressed for the remainder of the study. In the 200-and 2,000-g/L treatment groups, pH decreased similarly within 1 d of atrazine exposure and returned to control values within the following 16 d. The DO and pH did not differ significantly between the 0-and 20-g/L groups or the 200-and 2,000-g/L groups. Frogs from the two higher atrazine concentration treatment groups were 5% shorter and had 10% lower body mass at metamorphosis than those from the control and low atrazine concentration groups. No difference in length or body mass at metamorphosis was detectable between the 0-and 20-g/L groups or between the 200-and 2,000-g/L groups. Larval period was 5% longer in the 2,000-g/L group than in the 200-g/L group but did not differ from controls in any treatment group. No significant treatment-related differences were detected for survival rate. The decrease in amphibian length and weight at metamorphosis may indicate a reduction in fitness in wild populations of anurans exposed to atrazine at 200 to 2,000 g/L.

BackgroundThe zoonotic Orf virus (ORFV; genus Parapoxvirus, Poxviridae family) occurs worldwide and is transmitted between sheep and goats, wildlife and man. Archived tissue samples from 16 Alaskan wildlife cases, representing mountain goat (Oreamnos americanus, n = 8), Dall’s sheep (Ovis dalli dalli, n = 3), muskox (Ovibos moschatus, n = 3), Sitka black-tailed deer (Odocoileus hemionus sitkensis, n = 1) and caribou (Rangifer tarandus granti, n = 1), were analyzed.ResultsClinical signs and pathology were most severe in mountain goats, affecting most mucocutaneous regions, including palpebrae, nares, lips, anus, prepuce or vulva, as well as coronary bands. The proliferative masses were solid and nodular, covered by dark friable crusts. For Dall’s sheep lambs and juveniles, the gross lesions were similar to those of mountain goats, but not as extensive. The muskoxen displayed ulcerative lesions on the legs. The caribou had two ulcerative lesions on the upper lip, as well as lesions on the distal part of the legs, around the main and dew claws. A large hairless spherical mass, with the characteristics of a fibroma, was sampled from a Sitka black-tailed deer, which did not show proliferative lesions typical of an ORFV infection. Polymerase chain reaction analyses for B2L, GIF, vIL-10 and ATI demonstrated ORFV specific DNA in all cases. Sequences from Dall’s sheep formed a separate cluster, comparable to ORFV from domestic sheep. Sequences from the other species were different from the Dall’s sheep sequences, but almost identical to each other.ConclusionsThis is the first major investigation of parapoxvirus infections in large Alaskan game species, and the first report of parapoxvirus infection in caribou and Sitka black-tailed deer. This study shows that most of the wild ruminant species in Alaska and from most parts of Alaska, can carry and be affected by ORFV. These findings call for attention to transmission of ORFV from wildlife to livestock and to hunters, subsistence harvesters, and wildlife biologists.Electronic supplementary materialThe online version of this article (10.1186/s13028-018-0366-8) contains supplementary material, which is available to authorized users.

No abstract

The muskox ( Ovibos moschatus ) population inhabiting the eastern North Slope (ENS) of Alaska, US declined dramatically during 1999-2006, whereas populations in western Alaska (WA) were stable or increasing. To understand morbidity and mortality factors contributing to the decline, Alaska Department of Fish and Game conducted pathologic investigations of carcasses from 2005 until 2008. Additionally, archived sera from both ENS and WA muskoxen collected during 1984-92, before the documented beginning of the ENS decline; sera collected during 2000, near the beginning of the decline; and contemporary sera (from live capture-release, adult females) collected during 2006, 2007, and 2008 were analyzed to determine whether prevalence of antibody to potential pathogens differed in the two areas or changed over time. The pathogens investigated were those that were believed could cause lameness or poor reproduction or adversely affect general health. Furthermore, trace mineral levels, hemograms, and gastrointestinal parasites were evaluated in live adult females captured 2006-08. Pathologic investigations identified several comorbid conditions, including predation, polyarthritis caused by or consistent with Chlamydophila spp. infection, hoof lesions, copper deficiency, contagious ecthyma, verminous pneumonia, hepatic lipidosis suggestive of negative energy balance, and bacterial bronchopneumonia due to Trueperella pyogenes and Bibersteinia trehalosi . Pathogens suspected to be newly introduced in the ENS muskox population on the basis of serologic detection include bovine viral diarrhea, respiratory syncytial virus, Chlamydophila spp., Brucella spp., Coxiella burnetii , and Leptospira spp., whereas parainfluenza virus-3 antibody prevalence has increased in the WA population. Although multiple disease syndromes were identified that contributed to mortality and, in combination, likely limited the ENS muskox population, further holistic investigations of disease agents, trace mineral status, and nutritional factors in conjunction with intensive demographic and environmental analyses would provide a better understanding of factors that influence Alaskan muskox populations.

No abstract