Infectivity of sarcocystis spp. from bison, elk, moose, and cattle for cattle via sporocysts from coyotes

Bison bison (bison), Cervus canadensis (elk), Alces alces (moose), and Bos taurus (cattle) musculature containing Sarcocystis spp. cysts was fed to laboratory raised Canis latrans (coyotes), Sporocysts collected from the feces of coyotes fed musculature of each of the ruminant species were fed to four groups of three laboratory-raised domestic calves, respectively, to determine if Sarcocystis spp. was transmissible from wild to domestic ruminants and if so, to compare clinical signs of infection and morphologic features of cysts with those resulting from infection with Sarcocystis bovicanis. All calves fed sporocysts of Sarcocystis from coyotes that ate bison or cattle muscle had similar clinical signs and harbored morphologically similar parasites, suggesting that both bison and cattle are intermediate hosts for S. bovicanis and that this species is transmissible between the two ruminant species. All calves fed sporocysts from coyotes that ate elk muscle or moose muscle remained asymptomatic but one calf in each group had intramuscular cysts. The finding of relatively large numbers of intramuscular cysts in one calf fed sporocysts of elk origin and smaller numbers in one calf fed sporocysts of moose origin could represent either spurious natural infections or indicate low infectivity of Sarcocystis spp. from elk and moose to cattle.     

Molecular epidemiology of Brucella abortus isolates from cattle, elk, and bison in the United States, 1998 to 2011

A variable-number tandem repeat (VNTR) protocol targeting 10 loci in the Brucella abortus genome was used to assess genetic diversity among 366 field isolates recovered from cattle, bison, and elk in the Greater Yellowstone Area (GYA) and Texas during 1998 to 2011. Minimum spanning tree (MST) and unweighted-pair group method with arithmetic mean (UPGMA) analyses of VNTR data identified 237 different VNTR types, among which 14 prominent clusters of isolates could be identified. Cattle isolates from Texas segregated into three clusters: one comprised of field isolates from 1998 to 2005, one comprised of vaccination-associated infections, and one associated with an outbreak in Starr County in January 2011. An isolate obtained from a feral sow trapped on property adjacent to the Starr County herd in May 2011 clustered with the cattle isolates, suggesting a role for feral swine as B. abortus reservoirs in Starr County. Isolates from a 2005 cattle outbreak in Wyoming displayed VNTR-10 profiles matching those of strains recovered from Wyoming and Idaho elk. Additionally, isolates associated with cattle outbreaks in Idaho in 2002, Montana in 2008 and 2011, and Wyoming in 2010 primarily clustered with isolates recovered from GYA elk. This study indicates that elk play a predominant role in the transmission of B. abortus to cattle located in the GYA.     

Mortality in captive elk from salmonellosis

Salmonella typhimurium DT104 infections of captive elk (Cervus elaphus nelsoni) calves resulted in mortality in eight of 13 affected calves. Salmonellosis in these elk calves was characterized by diarrhea, fever, lethargy, inappetence and depression, and death usually ensued within 72 hr of initial clinical signs. Affected calves did not respond to antibiotic and fluid therapy. The source of the bacteria likely was one or more of the calves when they were captured in the wild at less than 5 days of age. In our captive holding facility, the disease spread quickly and was difficult to control. Phage typing, pulsed field gel electrophoresis, antibiotic sensitivity testing, and plasmid profiles determined that this Salmonella sp. strain was the epidemic strain common to cattle, sheep and humans.     

Comparison of abnormal prion protein glycoform patterns from transmissible spongiform encephalopathy agent-infected deer,elk, sheep,and cattle

Analysis of abnormal prion protein glycoform patterns from chronic wasting disease (CWD)-affected deer and elk, scrapie-affected sheep and cattle, and cattle with bovine spongiform encephalopathy failed to identify patterns capable of reliably distinguishing these transmissible spongiform encephalopathy diseases. However, PrP-res patterns sometimes differed among individual animals, suggesting infection by different or multiple CWD strains in some species.     

Ectoparasites from elk (Cervus elaphus nelsoni) from Wyoming

Hides of nine elk, collected during the winter of 1986-1987 from the National Elk Refuge, Wyoming (USA) were examined for ectoparasites. Parasites recovered were mites, Psoroptes sp. (five elk); lice, Solenopotes ferrisi and Bovicola (Bovicola) longicornis (seven elk); and winter ticks, Dermacentor albipictus (nine elk). Three elk with severe scabies had an estimated 0.6 x 10(6), 3.8 x 10(6) and 6.5 x 10(6) mites, respectively. Densities of mites were much higher in skin regions with severe dermatitis. Skin lesions on elk with scabies consisted of dense, often moist, scabs extending along the dorsal and lateral thoracic regions of the body. Lesions attributed to winter ticks consisted of broken hair and alopecia on the dorsal portion of the lower neck, often extending in a "collar" around the neck.     

Behavioral responses of male elk to hunting risk

Prey respond to predation risk with a range of behavioral tactics that can vary based on space use and hunting mode of the predator. Unlike other predators, human hunters are often more spatially and temporally restricted, which creates a period of short-duration, high-intensity predation risk for prey. Consequently, identifying the roles different hunting modes (i.e., archery and rifle), hunts for targeted and non-targeted species, and landscape features play in altering spatial and temporal responses of prey to predation risk by humans is important for effective management of harvested populations. From 2009 to 2016, we used a large-scale experiment including 50 animal-years of location data from 38 unique male elk (Cervus canadensis) to quantify changes in movement and resource selection in response to hunters during 3 separate 5-day controlled hunts for antlered males (elk archery, deer [Odocoileus spp.] rifle, and elk rifle) at the Starkey Experimental Forest and Range in northeast Oregon, USA. We evaluated competing hypotheses regarding elk responses to varying levels of prey risk posed by the different hunt types. We predicted that the strength of elk behavioral responses would increase with perceived hunter lethality (i.e., weak response to elk archery but similar response to elk and deer rifle hunts) and that prey response would be closely associated with hunter activity within the diel cycle (greater during diurnal than nocturnal hours) and across hunting seasons. Elk responses were strongest during diurnal hours when hunters were active on the landscape and were generally more pronounced during both rifle hunts than during the archery hunt (supporting our perceived lethality hypothesis). Male elk avoided open roads across all periods except during nocturnal hours of the breeding season and alternated between avoidance of areas with high canopy cover during nocturnal hours and selection during diurnal hours. In combination these patterns led to distinct distributional changes of male elk from pre-hunt to hunt periods. Patterns of male elk selection highlight the importance of managing for heterogeneous landscapes to meet a variety of habitat, harvest, hunter satisfaction, and escapement objectives.     

Transmission of elk and deer prions to transgenic mice

Chronic wasting disease (CWD) is a fatal prion disease in deer and elk. Unique among the prion diseases, it is transmitted among captive and free-ranging animals. To facilitate studies of the biology of CWD prions, we generated five lines of transgenic (Tg) mice expressing prion protein (PrP) from Rocky Mountain elk (Cervus elaphus nelsoni), denoted Tg(ElkPrP), and two lines of Tg mice expressing PrP common to white-tailed deer (Odocoileus virginianus) and mule deer (Odocoileus hemionus), denoted Tg(DePrP). None of the Tg(ElkPrP) or Tg(DePrP) mice exhibited spontaneous neurologic dysfunction at more than 600 days of age. Brain samples from CWD-positive elk, white-tailed deer, and mule deer produced disease in Tg(ElkPrP) mice between 180 and 200 days after inoculation and in Tg(DePrP) mice between 300 and 400 days. One of eight cervid brain inocula transmitted disease to Tg(MoPrP)4053 mice overexpressing wild-type mouse PrP-A in approximately 540 days. Neuropathologic analysis revealed abundant PrP amyloid plaques in the brains of ill mice. Brain homogenates from symptomatic Tg(ElkPrP) mice produced disease in 120 to 190 days in Tg(ElkPrP) mice. In contrast to the Tg(ElkPrP) and Tg(DePrP) mice, Tg mice overexpressing human, bovine, or ovine PrP did not develop prion disease after inoculation with CWD prions from among nine different isolates after >500 days. These findings suggest that CWD prions from elk, mule deer, and white-tailed deer can be readily transmitted among these three cervid species.     

Susceptibility to vancomycin of enterococci isolated from dairy products

The antibiotic vancomycin is often used in clinical therapy against multiple antibiotic-resistant bacteria. Twenty strains of enterococci, either Enterococcus faecium or Ent. faecalis , isolated from different cheeses were tested for resistance to vancomycin in liquid medium. Minimum inhibitory concentration (MIC) values ranged from less than 1 to 4 μg ml⁻¹. A 399 bp intragenic fragment of the van A gene was not observed after amplification of total DNA of the strains. It seems, therefore, that resistance to vancomycin, which is a common trait for enterococci of nosocomial origin, is not widespread among dairy isolates.     

Susceptibility of fungi isolated from clinical materials to voriconazole

The objective of the study was evaluation of the susceptibility of 139 fungal strains isolated from clinical materials to Voriconazole, a new antifungal agent of the triazole group. A dilution method was used. The drug was incorporated into the culture medium at concentrations 0.1-100 mg/l. It was found out that the antifungal effectiveness of the drug varied both between various fungal genera and species, and between strains within the same species. Total inhibition of the growth of 20% of the yeast-like fungi and 23.3% of the moulds was achieved at concentration 0.1 mg/l. It was documented that the species Candida guilliermondii, C. kefyr, Saccharomyces cerevisiae and Aspergillus fumigatus, that as a rule are resistant to triazoles, were highly susceptible to Voriconazole. Dermatophytes, too, were highly susceptible to the drug, particularly Trichophyton mentagrophytes and T. rubrum. The drug at concentration 0.1 mg/l totally inhibited 73.5% of the dermatophytes, and at concentration 1 mg/l--97.0% of them after 7 day incubation. After 14 day incubation, 97.0% of the strains were also inhibited at drug concentration not exceeding 1 mg/l.     

Responses of cattle to allergens from Boophilus microplus

Extracts of larvae of the cattle tick, Boophilus microplus, contain two allergens giving immediate hypersensitivity reactions in the skin of cattle which have been exposed to the tick. The partial purification of one of these is described. This, together with the other allergen whose purification has been described previously, was used to investigate the relationships between tick resistance, immediate hypersensitivity reactions, reaginic antibody levels as measured by Prausnitz-Küstner type reactions and serum levels of agglutinating antibody to one of the allergens. There were significant correlations between resistance and both the immediate hypersensitivity reactions and agglutinating antibody levels.