Journal of Veterinary Diagnostic Investigation, 2014
A total of 23 clinical isolates of Fusobacterium spp. were recovered at necropsy over a 2-year pe... more A total of 23 clinical isolates of Fusobacterium spp. were recovered at necropsy over a 2-year period from the respiratory tract of white-tailed deer ( Odocoileus virginianus). Isolates were identified as Fusobacterium varium (18/23), Fusobacterium necrophorum subsp. funduliforme (3/23), and Fusobacterium necrophorum subsp. necrophorum (2/23). Using polymerase chain reaction–based detection of virulence genes, all F. necrophorum isolates were positive for the promoter region of the leukotoxin operon and the hemagglutinin-related protein gene, while all F. varium isolates were negative. The presence of the leukotoxin gene in F. necrophorum isolates and the absence of this gene in F. varium isolates were confirmed by Southern hybridization using 2 separate probes. Toxicity to bovine polymorphonuclear leukocytes was observed with all F. necrophorum isolates, but was not observed in any F. varium isolates. Susceptibility to antimicrobials was markedly different for F. varium as compared...
In host–pathogen arms races, increases in host resistance prompt counteradaptation by pathogens, ... more In host–pathogen arms races, increases in host resistance prompt counteradaptation by pathogens, but the nature of that counteradaptation is seldom directly observed outside of laboratory models. The best-documented field example is the coevolution of myxoma virus (MYXV) in European rabbits. To understand how MYXV in Australia has continued to evolve in wild rabbits under intense selection for genetic resistance to myxomatosis, we compared the phenotypes of the progenitor MYXV and viral isolates from the 1950s and the 1990s in laboratory rabbits with no resistance. Strikingly, and unlike their 1950s counterparts, most virus isolates from the 1990s induced a highly lethal immune collapse syndrome similar to septic shock. Thus, the next step in this canonical case of coevolution after a species jump has been further escalation by the virus in the face of widespread host resistance.
Journal of the American Veterinary Medical Association, 2008
To determine current management practices used by white-tailed deer farms in Pennsylvania and ide... more To determine current management practices used by white-tailed deer farms in Pennsylvania and identify animal health problems that exist in these herds. Cross-sectional study. Owners and managers of 233 farms in Pennsylvania that raised white-tailed deer. A self-administered questionnaire was mailed to participants. Herds ranged in size from 1 to 350 deer. Land holdings ranged from 0.07 to 607 hectares (0.17 to 1,500 acres). Stocking density ranged from 0.1 to 118.6 deer/hectare (0.04 to 48 deer/acre). Most (84%) respondents raised deer for breeding or hunting stock; 13% raised deer exclusively as pets or for hobby purposes, and purpose varied by herd size. Multiple associations were identified between management or disease factors and herd size. The use of vaccines, use of veterinary and diagnostic services, use of pasture, and use of artificial insemination increased as herd size increased. The most common conditions in herds of all sizes were respiratory tract disease, diarrhea, parasitism, and sudden death. The prevalence of respiratory tract disease increased as herd size increased. Results suggested that many aspects of herd management for white-tailed deer farms in Pennsylvania were associated with herd size, but that regardless of herd size, many preventive medicine practices were improperly used or underused in many herds.
The current study describes isolation of Extraintestinal Pathogenic Escherichia coli (ExPEC) from... more The current study describes isolation of Extraintestinal Pathogenic Escherichia coli (ExPEC) from a juvenile male cat that died after being rescued from an animal hoarding incident. Grossly, there was evidence of pneumonia and renal abscessation. Histologically, there was diffuse interstitial pneumonia with necrosis and necrotizing and suppurative nephritis with colonies of coccobacilli. Within the lung, kidney, and mesentery there was necrotizing and suppurative vasculitis with thrombosis and coccobacilli. E. coli strain belonging to serotype O6:H1 that carried many of the virulence genes associated with ExPEC was isolated from the lung and kidney. The cat was part of a community of approximately 60 cats that lived in a house in a residential neighborhood, in which multiple cats had died. The case was of major significance to public health, as first responders, animal health professionals, and other community members were likely exposed to ExPEC, which is known to have zoonotic potential. It is important that pet owners, animal health and public health professionals, and first responders be made aware of the potential for zoonotic diseases.
Journal of Veterinary Diagnostic Investigation, 2004
The postmortem records of 160 white-tailed deer (Odocoileus virginianus) submitted for necropsy e... more The postmortem records of 160 white-tailed deer (Odocoileus virginianus) submitted for necropsy examination from 59 separate Pennsylvania captive deer farms over a 3.5-year period were reviewed to determine the primary cause of death of each animal. The most common causes of death were bronchopneumonia (39 cases), enterocolitis (30 cases), malnutrition (13 cases), and trauma (11 cases). Other causes of mortality included severe gastrointestinal parasitism (6 cases), cellulitis with septicemia (5 cases), degenerative myopathy (4 cases), ruminal acidosis (4 cases), and nephritis (4 cases). The cause of death was undetermined in 13 of the 160 animals. Arcanobacterium pyogenes (19 cases), Fusobacterium necrophorum (10 cases), Escherichia coli (7 cases), and Mannheimia haemolytica (4 cases) were the most commonly isolated bacteria from the pneumonic lungs. Bacterial agents associated with enterocolitis included Clostridium perfringens (15 cases), E. coli (12 cases), and Mycobacterium avium subsp. paratuberculosis (2 cases). The majority (52.2%) of the death loss in white-tailed deer of known ages occurred in animals 1 year of age or less, with 46.2% of the bronchopneumonia cases and 50.0% of the enterocolitis cases occurring during this time period. Cases of degenerative myopathy, myocardial degeneration, hepatic necrosis, meningoencephalitis, peritonitis, and urolithiasis considered severe enough to be the primary cause of death appeared early in life, affecting deer 6 months of age or less in all cases. In conclusion, bronchopneumonia, enterocolitis, malnutrition, and trauma were considered the most common causes of death in confined white-tailed deer in this study.
Journal of the American Veterinary Medical Association, 2008
To determine current management practices used by white-tailed deer farms in Pennsylvania and ide... more To determine current management practices used by white-tailed deer farms in Pennsylvania and identify animal health problems that exist in these herds. Cross-sectional study. Owners and managers of 233 farms in Pennsylvania that raised white-tailed deer. A self-administered questionnaire was mailed to participants. Herds ranged in size from 1 to 350 deer. Land holdings ranged from 0.07 to 607 hectares (0.17 to 1,500 acres). Stocking density ranged from 0.1 to 118.6 deer/hectare (0.04 to 48 deer/acre). Most (84%) respondents raised deer for breeding or hunting stock; 13% raised deer exclusively as pets or for hobby purposes, and purpose varied by herd size. Multiple associations were identified between management or disease factors and herd size. The use of vaccines, use of veterinary and diagnostic services, use of pasture, and use of artificial insemination increased as herd size increased. The most common conditions in herds of all sizes were respiratory tract disease, diarrhea, parasitism, and sudden death. The prevalence of respiratory tract disease increased as herd size increased. Results suggested that many aspects of herd management for white-tailed deer farms in Pennsylvania were associated with herd size, but that regardless of herd size, many preventive medicine practices were improperly used or underused in many herds.
Journal of Veterinary Diagnostic Investigation, 2014
A total of 23 clinical isolates of Fusobacterium spp. were recovered at necropsy over a 2-year pe... more A total of 23 clinical isolates of Fusobacterium spp. were recovered at necropsy over a 2-year period from the respiratory tract of white-tailed deer ( Odocoileus virginianus). Isolates were identified as Fusobacterium varium (18/23), Fusobacterium necrophorum subsp. funduliforme (3/23), and Fusobacterium necrophorum subsp. necrophorum (2/23). Using polymerase chain reaction–based detection of virulence genes, all F. necrophorum isolates were positive for the promoter region of the leukotoxin operon and the hemagglutinin-related protein gene, while all F. varium isolates were negative. The presence of the leukotoxin gene in F. necrophorum isolates and the absence of this gene in F. varium isolates were confirmed by Southern hybridization using 2 separate probes. Toxicity to bovine polymorphonuclear leukocytes was observed with all F. necrophorum isolates, but was not observed in any F. varium isolates. Susceptibility to antimicrobials was markedly different for F. varium as compared...
In host–pathogen arms races, increases in host resistance prompt counteradaptation by pathogens, ... more In host–pathogen arms races, increases in host resistance prompt counteradaptation by pathogens, but the nature of that counteradaptation is seldom directly observed outside of laboratory models. The best-documented field example is the coevolution of myxoma virus (MYXV) in European rabbits. To understand how MYXV in Australia has continued to evolve in wild rabbits under intense selection for genetic resistance to myxomatosis, we compared the phenotypes of the progenitor MYXV and viral isolates from the 1950s and the 1990s in laboratory rabbits with no resistance. Strikingly, and unlike their 1950s counterparts, most virus isolates from the 1990s induced a highly lethal immune collapse syndrome similar to septic shock. Thus, the next step in this canonical case of coevolution after a species jump has been further escalation by the virus in the face of widespread host resistance.
Journal of the American Veterinary Medical Association, 2008
To determine current management practices used by white-tailed deer farms in Pennsylvania and ide... more To determine current management practices used by white-tailed deer farms in Pennsylvania and identify animal health problems that exist in these herds. Cross-sectional study. Owners and managers of 233 farms in Pennsylvania that raised white-tailed deer. A self-administered questionnaire was mailed to participants. Herds ranged in size from 1 to 350 deer. Land holdings ranged from 0.07 to 607 hectares (0.17 to 1,500 acres). Stocking density ranged from 0.1 to 118.6 deer/hectare (0.04 to 48 deer/acre). Most (84%) respondents raised deer for breeding or hunting stock; 13% raised deer exclusively as pets or for hobby purposes, and purpose varied by herd size. Multiple associations were identified between management or disease factors and herd size. The use of vaccines, use of veterinary and diagnostic services, use of pasture, and use of artificial insemination increased as herd size increased. The most common conditions in herds of all sizes were respiratory tract disease, diarrhea, parasitism, and sudden death. The prevalence of respiratory tract disease increased as herd size increased. Results suggested that many aspects of herd management for white-tailed deer farms in Pennsylvania were associated with herd size, but that regardless of herd size, many preventive medicine practices were improperly used or underused in many herds.
The current study describes isolation of Extraintestinal Pathogenic Escherichia coli (ExPEC) from... more The current study describes isolation of Extraintestinal Pathogenic Escherichia coli (ExPEC) from a juvenile male cat that died after being rescued from an animal hoarding incident. Grossly, there was evidence of pneumonia and renal abscessation. Histologically, there was diffuse interstitial pneumonia with necrosis and necrotizing and suppurative nephritis with colonies of coccobacilli. Within the lung, kidney, and mesentery there was necrotizing and suppurative vasculitis with thrombosis and coccobacilli. E. coli strain belonging to serotype O6:H1 that carried many of the virulence genes associated with ExPEC was isolated from the lung and kidney. The cat was part of a community of approximately 60 cats that lived in a house in a residential neighborhood, in which multiple cats had died. The case was of major significance to public health, as first responders, animal health professionals, and other community members were likely exposed to ExPEC, which is known to have zoonotic potential. It is important that pet owners, animal health and public health professionals, and first responders be made aware of the potential for zoonotic diseases.
Journal of Veterinary Diagnostic Investigation, 2004
The postmortem records of 160 white-tailed deer (Odocoileus virginianus) submitted for necropsy e... more The postmortem records of 160 white-tailed deer (Odocoileus virginianus) submitted for necropsy examination from 59 separate Pennsylvania captive deer farms over a 3.5-year period were reviewed to determine the primary cause of death of each animal. The most common causes of death were bronchopneumonia (39 cases), enterocolitis (30 cases), malnutrition (13 cases), and trauma (11 cases). Other causes of mortality included severe gastrointestinal parasitism (6 cases), cellulitis with septicemia (5 cases), degenerative myopathy (4 cases), ruminal acidosis (4 cases), and nephritis (4 cases). The cause of death was undetermined in 13 of the 160 animals. Arcanobacterium pyogenes (19 cases), Fusobacterium necrophorum (10 cases), Escherichia coli (7 cases), and Mannheimia haemolytica (4 cases) were the most commonly isolated bacteria from the pneumonic lungs. Bacterial agents associated with enterocolitis included Clostridium perfringens (15 cases), E. coli (12 cases), and Mycobacterium avium subsp. paratuberculosis (2 cases). The majority (52.2%) of the death loss in white-tailed deer of known ages occurred in animals 1 year of age or less, with 46.2% of the bronchopneumonia cases and 50.0% of the enterocolitis cases occurring during this time period. Cases of degenerative myopathy, myocardial degeneration, hepatic necrosis, meningoencephalitis, peritonitis, and urolithiasis considered severe enough to be the primary cause of death appeared early in life, affecting deer 6 months of age or less in all cases. In conclusion, bronchopneumonia, enterocolitis, malnutrition, and trauma were considered the most common causes of death in confined white-tailed deer in this study.
Journal of the American Veterinary Medical Association, 2008
To determine current management practices used by white-tailed deer farms in Pennsylvania and ide... more To determine current management practices used by white-tailed deer farms in Pennsylvania and identify animal health problems that exist in these herds. Cross-sectional study. Owners and managers of 233 farms in Pennsylvania that raised white-tailed deer. A self-administered questionnaire was mailed to participants. Herds ranged in size from 1 to 350 deer. Land holdings ranged from 0.07 to 607 hectares (0.17 to 1,500 acres). Stocking density ranged from 0.1 to 118.6 deer/hectare (0.04 to 48 deer/acre). Most (84%) respondents raised deer for breeding or hunting stock; 13% raised deer exclusively as pets or for hobby purposes, and purpose varied by herd size. Multiple associations were identified between management or disease factors and herd size. The use of vaccines, use of veterinary and diagnostic services, use of pasture, and use of artificial insemination increased as herd size increased. The most common conditions in herds of all sizes were respiratory tract disease, diarrhea, parasitism, and sudden death. The prevalence of respiratory tract disease increased as herd size increased. Results suggested that many aspects of herd management for white-tailed deer farms in Pennsylvania were associated with herd size, but that regardless of herd size, many preventive medicine practices were improperly used or underused in many herds.
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