Polychlorinated biphenyl: interaction with duck hepatitis virus.

Ten-day-old mallard ducklings fed a polychlorinated biphenyl at concentrations of 25, 50, and 100 parts per million for 10 days suffered no apparent clinical intoxication. Five days later these birds were challenged with duck hepatitis virus, and they suffered significantly higher mortality than birds which were not exposed to the polychlorinated biphenyl.

Salmonella enteritidis and Arizona hinshawii isolated from wild sandhill cranes.

Salmonella enteritidis serotype Rubislaw and Arizona hinshawii were isolated from cloacal swabs of "healthy" live-trapped sandhill cranes (Grus canadensis tabida) in Indiana and Wisconsin. These respective isolations were the first reported from wild sandhill cranes.

The use of wildlife to monitor zoonoses.

Wildlife are usually considered vectors, reservoirs or primary targets of infectious disease. A seldom considered epidemiological role which they can play involves their use as disease sentinels for the detection and monitoring of zoonoses. Their potential for such utilization has been demonstrated with the wild turkey (Meleagris gallopava intermedia) and St. Louis encephalitis in Texas and the white-tailed deer (Odocoileus virginianus) and California encephalitis in North America. The limitations and criteria which are important in the use of wild populations for "sentinel" duty are discussed.

Serologic evidence of Venezuelan equine encephalitis in some wild and domestic populations of southern Texas.

More than 2,500 sera from approximately 30 wild and domestic species in southern Texas were tested for neutralizing antibodies to Venezuelan equine encephalitis (VEE). Virus isolations were also attempted from blood and tissue samples of many of the wild specimens. VEE neutralizing substances were present in a variety of species collected prior to the 1971 epizootic, suggesting that VEE was present and perhaps enzootic in this area before the recent epizootic. Serologic results of this study suggest that deer (Odocoileus virginianus) and feral swine (Sus scrofa) may serve as good indicators or sentinels of VEE transmission. The reservoir of VEE was not established, but results of the study suggest that a number of species or a combination of animal host populations including deer, feral swine, and peccaries (Pecari angulatus) may be involved in the eizootiologyof VEE in southern Texas.

Experimental haemonchosis in white-tailed deer.

White-tailed deer (Odocoileus virginianus) were successfully infected with Haemonchus contortus of sheep origin. Individual deer in each of three groups were inoculated with 0, 25,000, and 100,000 larvae respectively. Severity of infection was related to dose and signs of infection were most obvious in the heavily inoculated animals. Infected deer were weak, emaciated, and anemic, similar to the clinical response in sheep. Hemoglobin, packed cell volume, and total serum protein values for both infected groups were significantly lower than for the controls. Inhibition of larval growth was noted in both infected groups, but was most pronounced in the group which received 100,000 larvae. Inhibition of egg production was also noted in this group. The potential importance of H. cortortus in deer populations was discussed.

Bluetongue virus: (1) in pregnant white-tailed deer (2) a plaque reduction neutralization test.

Six white-tailed deer (Odocoileus virginianus) were infected with bluetongue virus (BTs, vaccinal strain) approximately one-third of the way through their gestation period. One deer died of bluetongue 21 days after inoculation. Of the five surviving the infection, one had two mummified fetuses, and the others no fetuses upon euthanasia two weeks after term. Fetuses were present in two control deer and in the one which died of bluetongue. A plaque reduction neutralization test for bluetongue virus was developed and described for the first time and its sensitivity illustrated by high post inoculation titers which ranged from 1:3200 to greater than 1:16000.

Isolation of a bunyamwera group arbovirus from a naturally infected caribou.

A Bunyamwera group arbovirus was isolated from the blood and from the brain of a female caribou parasitized with meningeal worms. The virus passed through a 0.45 micron filter; was ether sensitive; possessed no hemagglutination properties; could be propagated in suckling mice, 6-day old chick embryos, and BHK-21 tissue culture; and produced plaques in chick embryo fibroblast tissue culture. Neither complement-fixation or neutralization tests were sensitive enough to determine the serotype of the virus.

Serologic evidence of bunyamwera group arbovirus infections in Wisconsin and texas deer.

Sera of 81 white-tailed deer from south Texas and 283 white-tailed deer from Wisconsin were tested for neutralizing and hemagglutination-inhibiting antibodies to arboviruses of the Bunyamwera group. Neutralizing antibodies were detected in 100% of the Texas deer sera and hemagglutination-inhibiting antibodies were detected in 61% of those sera collected in 1969 and 78% of those sera collected in 1963. The prevalence of both neutralizing and hemagglutination-inhibiting antibodies in Wisconsin deer sera varied from 72-100% and 42-79% respectively depending on the geographic area tested in the years 1963 and 1969.

Serologic examination of wild birds for hemorrhagic enteritis of Turkey and marble spleen disease of pheasants.

Precipitin antibody which reacted with the hemorrhagic enteritis (HE) of turkeys/marble spleen disease (MSD) of pheasants group of avian adenoviruses, was not detected in serum samples of 618 wild birds (42 species) from Florida, Texas and Virginia. HE/MSD precipitin antibody was detected in serum samples of pen-reared ring-necked pheasants ( Phasianus colchicus ) which had experienced MSD, but not in serum samples of similar MSD unaffected birds.

Epidemiologic study of canine blastomycosis in Wisconsin.

An epidemiologic study was designed to investigate the increasing number of cases of canine blastomycosis being reported in Wisconsin. From January 1980 through July 1982, 200 cases of canine blastomycosis from 39 Wisconsin counties were examined to assess epidemiologic and environmental aspects of this disease. Based on a survey of 176 dog owners, principal disease characteristics for canine blastomycosis were anorexia, lethargy, shortness of breath, chronic cough, and weight loss. The greatest number of cases of canine blastomycosis was in the northwest, north central, northeast, central, and southeast regions of Wisconsin. The northeast and central regions were determined to be new enzootic areas. Sporting breeds accounted for the largest percentage of cases among the various breeds of dogs in Wisconsin. Most of the affected dogs were 3 years old or younger and there was no apparent sexual predilection. Canine blastomycosis was diagnosed more frequently from late spring through late fall. Enzootic areas, except for the southeast region of Wisconsin, were located where the soil was sandy and acid. The results of this study suggested a possible association of enzootic areas with waterways, especially impoundments.