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Tonie Rocke

Tonie Rocke is a Research Epidemiologist at the National Wildlife Health Center.

Science and Products

A small brown bat sits on the side of a tree

Dynamics of Rabies Transmission in Vampire Bats and Potential for Control Through Vaccination

Vampire bats are the primary spreader of rabies, a lethal disease that harms livestock and people across Latin America. Growth of the livestock industry and environmental changes in this region are leading to the expansion of vampire bats’ habitat range, and it is considered likely this species will move into the southern United States.
By
Ecosystems Mission Area, Biological Threats and Invasive Species Research Program, National Wildlife Health Center
Dynamics of Rabies Transmission in Vampire Bats and Potential for Control Through Vaccination

Dynamics of Rabies Transmission in Vampire Bats and Potential for Control Through Vaccination

Vampire bats are the primary spreader of rabies, a lethal disease that harms livestock and people across Latin America. Growth of the livestock industry and environmental changes in this region are leading to the expansion of vampire bats’ habitat range, and it is considered likely this species will move into the southern United States.
Learn More
Gloved hands holding a bat white glove scientists administers vaccine orally.

White-nose Syndrome Vaccine Updates

Since its emergence in 2006, white-nose syndrome (WNS) continues to spread in North America and has substantially impacted hibernating bat populations, contributing to declines of over 90% in northern long-eared ( Myotis septentrionalis), little brown ( Myotis lucifugus), and tri-colored bat ( Perimyotis subflavus) populations. We are developing tools and management strategies to protect bat...
By
Ecosystems Mission Area, Biological Threats and Invasive Species Research Program, National Wildlife Health Center
White-nose Syndrome Vaccine Updates

White-nose Syndrome Vaccine Updates

Since its emergence in 2006, white-nose syndrome (WNS) continues to spread in North America and has substantially impacted hibernating bat populations, contributing to declines of over 90% in northern long-eared ( Myotis septentrionalis), little brown ( Myotis lucifugus), and tri-colored bat ( Perimyotis subflavus) populations. We are developing tools and management strategies to protect bat...
Learn More
Cluster of bats on a cave wall.

Field trials for testing of white-nose syndrome vaccine candidates

White-nose syndrome (WNS), caused by the fungus Pseudogymnoascus destructans (Pd), continues to decimate bat populations in North America, and efforts to develop treatment options have intensified. One potential method for controlling WNS is vaccination of bats with specific antigens to elicit a protective immune response.
By
Ecosystems Mission Area, Biological Threats and Invasive Species Research Program, National Wildlife Health Center
Field trials for testing of white-nose syndrome vaccine candidates

Field trials for testing of white-nose syndrome vaccine candidates

White-nose syndrome (WNS), caused by the fungus Pseudogymnoascus destructans (Pd), continues to decimate bat populations in North America, and efforts to develop treatment options have intensified. One potential method for controlling WNS is vaccination of bats with specific antigens to elicit a protective immune response.
Learn More
Image: Black-Footed Ferret

Development of SARS-CoV-2 vaccine to support black-footed ferret conservation

The SARS-CoV-2 virus is known to infect and cause severe disease, such as respiratory distress and death, in mustelids, including farm-raised mink ( Mustela  lutreola and  Neovison  vison) and domestic ferrets ( M. putorius). This raised concern that the virus may also pose a threat to endangered black-footed ferrets ( Mustela nigripes) managed in captivity for breeding and recovery purposes.
By
Ecosystems Mission Area, Biological Threats and Invasive Species Research Program, National Wildlife Health Center
Development of SARS-CoV-2 vaccine to support black-footed ferret conservation

Development of SARS-CoV-2 vaccine to support black-footed ferret conservation

The SARS-CoV-2 virus is known to infect and cause severe disease, such as respiratory distress and death, in mustelids, including farm-raised mink ( Mustela  lutreola and  Neovison  vison) and domestic ferrets ( M. putorius). This raised concern that the virus may also pose a threat to endangered black-footed ferrets ( Mustela nigripes) managed in captivity for breeding and recovery purposes.
Learn More
Little brown bat (Myotis lucifugus) in the Shipp Room, Hellhole cave

Modeling the response of cave hibernating Myotis species to white-nose syndrome mitigation tactics

Bat Research Research collaboration: Robin Russell (NWHC), Tonie Rocke (NWHC), Wayne Thogmartin (UMESC), Evan Grant (EESC) White-nose syndrome is a fungal disease devastating cave-hibernating bat species ( Myotis spp.) in the eastern United States. Several mitigation tactics have been proposed to alleviate the effects of white-nose syndrome on bats including probiotics and vaccination. Questions...
By
Biological Threats and Invasive Species Research Program, Species Management Research Program, National Wildlife Health Center, Upper Midwest Environmental Sciences Center
Modeling the response of cave hibernating Myotis species to white-nose syndrome mitigation tactics

Modeling the response of cave hibernating Myotis species to white-nose syndrome mitigation tactics

Bat Research Research collaboration: Robin Russell (NWHC), Tonie Rocke (NWHC), Wayne Thogmartin (UMESC), Evan Grant (EESC) White-nose syndrome is a fungal disease devastating cave-hibernating bat species ( Myotis spp.) in the eastern United States. Several mitigation tactics have been proposed to alleviate the effects of white-nose syndrome on bats including probiotics and vaccination. Questions...
Learn More
Image: Plague Vaccine Bait

Vaccines

The USGS National Wildlife Health Center (NWHC) works on developing various disease management tools, including the development of vaccines. Our current work focuses on vaccines for sylvatic plague, white-nose syndrome, and rabies as disease control strategies.
By
Ecosystems Mission Area, Biological Threats and Invasive Species Research Program, National Wildlife Health Center
Vaccines

Vaccines

The USGS National Wildlife Health Center (NWHC) works on developing various disease management tools, including the development of vaccines. Our current work focuses on vaccines for sylvatic plague, white-nose syndrome, and rabies as disease control strategies.
Learn More
Prairie dog and SPV bait

Sylvatic Plague

Sylvatic plague, caused by Yersinia pestis, is a bacterial disease transmitted by fleas that afflicts many mammalian species, including humans.
By
Ecosystems Mission Area, Biological Threats and Invasive Species Research Program, National Wildlife Health Center
Sylvatic Plague

Sylvatic Plague

Sylvatic plague, caused by Yersinia pestis, is a bacterial disease transmitted by fleas that afflicts many mammalian species, including humans.
Learn More
Image: Bat with White-nose Syndrome

White-Nose Syndrome

White-nose syndrome (WNS) is an emergent disease of hibernating bats that has spread from the northeastern across United States at an alarming rate.
By
Ecosystems Mission Area, Biological Threats and Invasive Species Research Program, National Wildlife Health Center
White-Nose Syndrome

White-Nose Syndrome

White-nose syndrome (WNS) is an emergent disease of hibernating bats that has spread from the northeastern across United States at an alarming rate.
Learn More
Mosquito, species not verified

Vector-Borne Diseases

Vector-borne diseases are transmitted from one animal to another by vectors, including insects, such as mosquitoes or fleas, and arachnids, such as ticks. The USGS National Wildlife Health Center investigates wildlife diseases, including vector-borne diseases, such as West Nile virus and sylvatic plague.
By
Ecosystems Mission Area, Biological Threats and Invasive Species Research Program, National Wildlife Health Center
Vector-Borne Diseases

Vector-Borne Diseases

Vector-borne diseases are transmitted from one animal to another by vectors, including insects, such as mosquitoes or fleas, and arachnids, such as ticks. The USGS National Wildlife Health Center investigates wildlife diseases, including vector-borne diseases, such as West Nile virus and sylvatic plague.
Learn More
Filter Total Items: 16
No Result Found
No results found.
Filter Total Items: 135

Epizootiologic studies of avian vacuolar myelinopathy in waterbirds Epizootiologic studies of avian vacuolar myelinopathy in waterbirds

Epizootic avian vacuolar myelinopathy (AVM) was first recognized as a neurologic disease in bald eagles (Haliaeetus leucocephalus) and American coots (Fulica americana) in Arkansas, USA in 1994 and 1996, respectively, but attempts to identify the etiology of the disease have been unsuccessful to date. Between 1998 and 2001, wing clipped sentinel birds (wild American coots and game farm...
Authors
Tonie E. Rocke, N. J. Thomas, T. Augspurger, Kimberli Miller
By
Ecosystems Mission Area, National Wildlife Health Center

Clinical features of avian vacuolar myelinopathy in American coots Clinical features of avian vacuolar myelinopathy in American coots

Objective—To characterize clinical features of avian vacuolar myelinopathy (AVM) in American coots. Design—Case-control study. Animals—26 AVM-affected American coots and 12 unaffected coots. Procedures—Complete physical, neurologic, hematologic, and plasma biochemical evaluations were performed. Affected coots received supportive care. All coots died or were euthanatized, and AVM status...
Authors
R. S. Larsen, Felicia B. Nutter, T. Augspurger, Tonie E. Rocke, L. Tomlinson, Nancy J. Thomas, M. K. Stoskopf
By
Ecosystems Mission Area, National Wildlife Health Center

Avian vacuolar myelinopathy: a newly recognized fatal neurologic disease of eagles, waterfowl, and other birds Avian vacuolar myelinopathy: a newly recognized fatal neurologic disease of eagles, waterfowl, and other birds

Wildlife biologists and health specialists have been frustrated by a long list of negative findings in their AVM investigations, however studies continue to provide pieces of information to aid the determination of the cause and its source. Available data indicated that AVM may have been present since at least 1990, occurs in at least five states, has been documented during October...
Authors
John R. Fischer, L.A. Lewis, T. Augspurger, Tonie E. Rocke
By
Ecosystems Mission Area, National Wildlife Health Center

Pleurochrysis pseudoroscoffensis (Prymnesiophyceae) blooms on the surface of the Salton Sea, California Pleurochrysis pseudoroscoffensis (Prymnesiophyceae) blooms on the surface of the Salton Sea, California

Dense populations of the coccolithophore Pleurochrysis pseudoroscoffensis were found in surface films at several locations around the Salton Sea in February–August, 1999. An unidentified coccolithophorid was also found in low densities in earlier studies of the lake (1955–1956). To our knowledge, this is the first record of this widespread marine species in any lake. Samples taken from...
Authors
Kristen M. Reifel, M. P. McCoy, M. A. Tiffany, Tonie E. Rocke, Charles Trees, S. B. Barlow, D. J. Faulkner, S. H. Hurlbert
By
Ecosystems Mission Area, National Wildlife Health Center, Salton Sea

Desert bighorn sheep mortality due to presumptive type C botulism in California Desert bighorn sheep mortality due to presumptive type C botulism in California

During a routine telemetry flight of the Mojave Desert (California, USA) in August 1995, mortality signals were detected from two of 12 radio-collared female desert bighorn sheep (Ovis canadensis) in the vicinity of Old Dad Peak in San Bernardino County (California). A series of field investigations determined that at least 45 bighorn sheep had died near two artificial water catchments...
Authors
P. K. Swift, J. D. Wehausen, H. B. Ernest, R. S. Singer, A. M. Pauli, H. Kinde, Tonie E. Rocke, V. C. Bleich
By
Ecosystems Mission Area, National Wildlife Health Center

Efficacy of a type C botulism vaccine in green-winged teal Efficacy of a type C botulism vaccine in green-winged teal

We tested the efficacy of a single dose of Botumink toxoid for protecting wild green-winged teal (Anas crecca) during botulism epizootics caused by Clostridium botulinum type C. We challenged control and immunized ducks with four different doses of type C botulinum toxin to determine the LD50 for this species and to evaluate vaccine protection. Fewer immunized ducks were affected with...
Authors
Tonie E. Rocke, M.D. Samuel, P. K. Swift, G.S. Yarris
By
Ecosystems Mission Area, National Wildlife Health Center

Type C botulism in dairy cattle from feed contaminated with a dead cat Type C botulism in dairy cattle from feed contaminated with a dead cat

Four hundred twenty-seven of 441 adult Holstein dairy cattle from a 1,200-cow dairy died over a 1-week period during early spring 1998. Affected animals were from 4 late lactation pens, one of which included the bull string. Signs included weakness, recumbency, watery diarrhea, and death. Eighty animals from the 4 pens were dead approximately 8 hours after the first ill cows were noted...
Authors
F.D. Galey, R. Terra, R. Walker, J. Adaska, M.A. Etchebarne, B. Puschener, R.H. Whitlock, Tonie E. Rocke, D. Willoughby, E. Tor
By
Ecosystems Mission Area, National Wildlife Health Center

Water and sediment characteristics associated with avian botulism outbreaks in wetlands Water and sediment characteristics associated with avian botulism outbreaks in wetlands

Avian botulism kills thousands of waterbirds annually throughout North America, but management efforts to reduce its effects have been hindered because environmental conditions that promote outbreaks are poorly understood. We measured sediment and water variables in 32 pairs of wetlands with and without a current outbreak of avian botulism. Wetlands with botulism outbreaks had greater...
Authors
Tonie E. Rocke, Michael D. Samuel
By
Ecosystems Mission Area, National Wildlife Health Center

Avian botulism Avian botulism

Avian botulism is a paralytic, often fatal, disease of birds that results when they ingest toxin produced by the bacterium, Clostridium botulinum. Seven distinct types of toxin designated by the letters A to G have been identified (Table 38.1). Waterfowl die-offs due to botulism are usually caused by type C toxin; sporadic die-offs among fish-eating birds, such as common loons and gulls...
Authors
Tonie E. Rocke, M. Friend
By
Ecosystems Mission Area, National Wildlife Health Center

Oil Oil

Each year, an average of 14 million gallons of oil from more than 10,000 accidental spills flow into fresh and saltwater environments in and around the United States. Most accidental oil spills occur when oil is transported by tankers or barges, but oil is also spilled during highway, rail, and pipeline transport, and by nontransportation-related facilities, such as refinery, bulk...
Authors
Tonie E. Rocke
By
Ecosystems Mission Area, National Wildlife Health Center

In situ detection of the Clostridium botulinum type C1 toxin gene in wetland sediments with a nested PCR assay In situ detection of the Clostridium botulinum type C1 toxin gene in wetland sediments with a nested PCR assay

A nested PCR was developed for detection of the Clostridium botulinum type C1 toxin gene in sediments collected from wetlands where avian botulism outbreaks had or had not occurred. The C1 toxin gene was detected in 16 of 18 sites, demonstrating both the ubiquitous distribution of C. botulinum type C in wetland sediments and the sensitivity of the detection assay.
Authors
Judy L. Williamson, Tonie E. Rocke, Judd M. Aiken
By
Ecosystems Mission Area, National Wildlife Health Center

Environmental characteristics associated with the occurrence of avian botulism in wetlands of a northern California refuge Environmental characteristics associated with the occurrence of avian botulism in wetlands of a northern California refuge

Avian botulism is an important disease affecting many species of waterbirds in North America, but the environmental conditions that initiate outbreaks are poorly understood. To determine wetland attributes associated with outbreaks of avian botulism in waterbirds at the Sacramento National Wildlife Refuge (SNWR), California, we compared environmental characteristics between wetlands...
Authors
Tonie E. Rocke, Ned H. Euliss, Michael D. Samuel
By
Ecosystems Mission Area, Northern Prairie Wildlife Research Center, National Wildlife Health Center

Science and Products

A small brown bat sits on the side of a tree

Dynamics of Rabies Transmission in Vampire Bats and Potential for Control Through Vaccination

Vampire bats are the primary spreader of rabies, a lethal disease that harms livestock and people across Latin America. Growth of the livestock industry and environmental changes in this region are leading to the expansion of vampire bats’ habitat range, and it is considered likely this species will move into the southern United States.
By
Ecosystems Mission Area, Biological Threats and Invasive Species Research Program, National Wildlife Health Center
Dynamics of Rabies Transmission in Vampire Bats and Potential for Control Through Vaccination

Dynamics of Rabies Transmission in Vampire Bats and Potential for Control Through Vaccination

Vampire bats are the primary spreader of rabies, a lethal disease that harms livestock and people across Latin America. Growth of the livestock industry and environmental changes in this region are leading to the expansion of vampire bats’ habitat range, and it is considered likely this species will move into the southern United States.
Learn More
Gloved hands holding a bat white glove scientists administers vaccine orally.

White-nose Syndrome Vaccine Updates

Since its emergence in 2006, white-nose syndrome (WNS) continues to spread in North America and has substantially impacted hibernating bat populations, contributing to declines of over 90% in northern long-eared ( Myotis septentrionalis), little brown ( Myotis lucifugus), and tri-colored bat ( Perimyotis subflavus) populations. We are developing tools and management strategies to protect bat...
By
Ecosystems Mission Area, Biological Threats and Invasive Species Research Program, National Wildlife Health Center
White-nose Syndrome Vaccine Updates

White-nose Syndrome Vaccine Updates

Since its emergence in 2006, white-nose syndrome (WNS) continues to spread in North America and has substantially impacted hibernating bat populations, contributing to declines of over 90% in northern long-eared ( Myotis septentrionalis), little brown ( Myotis lucifugus), and tri-colored bat ( Perimyotis subflavus) populations. We are developing tools and management strategies to protect bat...
Learn More
Cluster of bats on a cave wall.

Field trials for testing of white-nose syndrome vaccine candidates

White-nose syndrome (WNS), caused by the fungus Pseudogymnoascus destructans (Pd), continues to decimate bat populations in North America, and efforts to develop treatment options have intensified. One potential method for controlling WNS is vaccination of bats with specific antigens to elicit a protective immune response.
By
Ecosystems Mission Area, Biological Threats and Invasive Species Research Program, National Wildlife Health Center
Field trials for testing of white-nose syndrome vaccine candidates

Field trials for testing of white-nose syndrome vaccine candidates

White-nose syndrome (WNS), caused by the fungus Pseudogymnoascus destructans (Pd), continues to decimate bat populations in North America, and efforts to develop treatment options have intensified. One potential method for controlling WNS is vaccination of bats with specific antigens to elicit a protective immune response.
Learn More
Image: Black-Footed Ferret

Development of SARS-CoV-2 vaccine to support black-footed ferret conservation

The SARS-CoV-2 virus is known to infect and cause severe disease, such as respiratory distress and death, in mustelids, including farm-raised mink ( Mustela  lutreola and  Neovison  vison) and domestic ferrets ( M. putorius). This raised concern that the virus may also pose a threat to endangered black-footed ferrets ( Mustela nigripes) managed in captivity for breeding and recovery purposes.
By
Ecosystems Mission Area, Biological Threats and Invasive Species Research Program, National Wildlife Health Center
Development of SARS-CoV-2 vaccine to support black-footed ferret conservation

Development of SARS-CoV-2 vaccine to support black-footed ferret conservation

The SARS-CoV-2 virus is known to infect and cause severe disease, such as respiratory distress and death, in mustelids, including farm-raised mink ( Mustela  lutreola and  Neovison  vison) and domestic ferrets ( M. putorius). This raised concern that the virus may also pose a threat to endangered black-footed ferrets ( Mustela nigripes) managed in captivity for breeding and recovery purposes.
Learn More
Little brown bat (Myotis lucifugus) in the Shipp Room, Hellhole cave

Modeling the response of cave hibernating Myotis species to white-nose syndrome mitigation tactics

Bat Research Research collaboration: Robin Russell (NWHC), Tonie Rocke (NWHC), Wayne Thogmartin (UMESC), Evan Grant (EESC) White-nose syndrome is a fungal disease devastating cave-hibernating bat species ( Myotis spp.) in the eastern United States. Several mitigation tactics have been proposed to alleviate the effects of white-nose syndrome on bats including probiotics and vaccination. Questions...
By
Biological Threats and Invasive Species Research Program, Species Management Research Program, National Wildlife Health Center, Upper Midwest Environmental Sciences Center
Modeling the response of cave hibernating Myotis species to white-nose syndrome mitigation tactics

Modeling the response of cave hibernating Myotis species to white-nose syndrome mitigation tactics

Bat Research Research collaboration: Robin Russell (NWHC), Tonie Rocke (NWHC), Wayne Thogmartin (UMESC), Evan Grant (EESC) White-nose syndrome is a fungal disease devastating cave-hibernating bat species ( Myotis spp.) in the eastern United States. Several mitigation tactics have been proposed to alleviate the effects of white-nose syndrome on bats including probiotics and vaccination. Questions...
Learn More
Image: Plague Vaccine Bait

Vaccines

The USGS National Wildlife Health Center (NWHC) works on developing various disease management tools, including the development of vaccines. Our current work focuses on vaccines for sylvatic plague, white-nose syndrome, and rabies as disease control strategies.
By
Ecosystems Mission Area, Biological Threats and Invasive Species Research Program, National Wildlife Health Center
Vaccines

Vaccines

The USGS National Wildlife Health Center (NWHC) works on developing various disease management tools, including the development of vaccines. Our current work focuses on vaccines for sylvatic plague, white-nose syndrome, and rabies as disease control strategies.
Learn More
Prairie dog and SPV bait

Sylvatic Plague

Sylvatic plague, caused by Yersinia pestis, is a bacterial disease transmitted by fleas that afflicts many mammalian species, including humans.
By
Ecosystems Mission Area, Biological Threats and Invasive Species Research Program, National Wildlife Health Center
Sylvatic Plague

Sylvatic Plague

Sylvatic plague, caused by Yersinia pestis, is a bacterial disease transmitted by fleas that afflicts many mammalian species, including humans.
Learn More
Image: Bat with White-nose Syndrome

White-Nose Syndrome

White-nose syndrome (WNS) is an emergent disease of hibernating bats that has spread from the northeastern across United States at an alarming rate.
By
Ecosystems Mission Area, Biological Threats and Invasive Species Research Program, National Wildlife Health Center
White-Nose Syndrome

White-Nose Syndrome

White-nose syndrome (WNS) is an emergent disease of hibernating bats that has spread from the northeastern across United States at an alarming rate.
Learn More
Mosquito, species not verified

Vector-Borne Diseases

Vector-borne diseases are transmitted from one animal to another by vectors, including insects, such as mosquitoes or fleas, and arachnids, such as ticks. The USGS National Wildlife Health Center investigates wildlife diseases, including vector-borne diseases, such as West Nile virus and sylvatic plague.
By
Ecosystems Mission Area, Biological Threats and Invasive Species Research Program, National Wildlife Health Center
Vector-Borne Diseases

Vector-Borne Diseases

Vector-borne diseases are transmitted from one animal to another by vectors, including insects, such as mosquitoes or fleas, and arachnids, such as ticks. The USGS National Wildlife Health Center investigates wildlife diseases, including vector-borne diseases, such as West Nile virus and sylvatic plague.
Learn More
Filter Total Items: 16
No Result Found
No results found.
Filter Total Items: 135

Epizootiologic studies of avian vacuolar myelinopathy in waterbirds Epizootiologic studies of avian vacuolar myelinopathy in waterbirds

Epizootic avian vacuolar myelinopathy (AVM) was first recognized as a neurologic disease in bald eagles (Haliaeetus leucocephalus) and American coots (Fulica americana) in Arkansas, USA in 1994 and 1996, respectively, but attempts to identify the etiology of the disease have been unsuccessful to date. Between 1998 and 2001, wing clipped sentinel birds (wild American coots and game farm...
Authors
Tonie E. Rocke, N. J. Thomas, T. Augspurger, Kimberli Miller
By
Ecosystems Mission Area, National Wildlife Health Center

Clinical features of avian vacuolar myelinopathy in American coots Clinical features of avian vacuolar myelinopathy in American coots

Objective—To characterize clinical features of avian vacuolar myelinopathy (AVM) in American coots. Design—Case-control study. Animals—26 AVM-affected American coots and 12 unaffected coots. Procedures—Complete physical, neurologic, hematologic, and plasma biochemical evaluations were performed. Affected coots received supportive care. All coots died or were euthanatized, and AVM status...
Authors
R. S. Larsen, Felicia B. Nutter, T. Augspurger, Tonie E. Rocke, L. Tomlinson, Nancy J. Thomas, M. K. Stoskopf
By
Ecosystems Mission Area, National Wildlife Health Center

Avian vacuolar myelinopathy: a newly recognized fatal neurologic disease of eagles, waterfowl, and other birds Avian vacuolar myelinopathy: a newly recognized fatal neurologic disease of eagles, waterfowl, and other birds

Wildlife biologists and health specialists have been frustrated by a long list of negative findings in their AVM investigations, however studies continue to provide pieces of information to aid the determination of the cause and its source. Available data indicated that AVM may have been present since at least 1990, occurs in at least five states, has been documented during October...
Authors
John R. Fischer, L.A. Lewis, T. Augspurger, Tonie E. Rocke
By
Ecosystems Mission Area, National Wildlife Health Center

Pleurochrysis pseudoroscoffensis (Prymnesiophyceae) blooms on the surface of the Salton Sea, California Pleurochrysis pseudoroscoffensis (Prymnesiophyceae) blooms on the surface of the Salton Sea, California

Dense populations of the coccolithophore Pleurochrysis pseudoroscoffensis were found in surface films at several locations around the Salton Sea in February–August, 1999. An unidentified coccolithophorid was also found in low densities in earlier studies of the lake (1955–1956). To our knowledge, this is the first record of this widespread marine species in any lake. Samples taken from...
Authors
Kristen M. Reifel, M. P. McCoy, M. A. Tiffany, Tonie E. Rocke, Charles Trees, S. B. Barlow, D. J. Faulkner, S. H. Hurlbert
By
Ecosystems Mission Area, National Wildlife Health Center, Salton Sea

Desert bighorn sheep mortality due to presumptive type C botulism in California Desert bighorn sheep mortality due to presumptive type C botulism in California

During a routine telemetry flight of the Mojave Desert (California, USA) in August 1995, mortality signals were detected from two of 12 radio-collared female desert bighorn sheep (Ovis canadensis) in the vicinity of Old Dad Peak in San Bernardino County (California). A series of field investigations determined that at least 45 bighorn sheep had died near two artificial water catchments...
Authors
P. K. Swift, J. D. Wehausen, H. B. Ernest, R. S. Singer, A. M. Pauli, H. Kinde, Tonie E. Rocke, V. C. Bleich
By
Ecosystems Mission Area, National Wildlife Health Center

Efficacy of a type C botulism vaccine in green-winged teal Efficacy of a type C botulism vaccine in green-winged teal

We tested the efficacy of a single dose of Botumink toxoid for protecting wild green-winged teal (Anas crecca) during botulism epizootics caused by Clostridium botulinum type C. We challenged control and immunized ducks with four different doses of type C botulinum toxin to determine the LD50 for this species and to evaluate vaccine protection. Fewer immunized ducks were affected with...
Authors
Tonie E. Rocke, M.D. Samuel, P. K. Swift, G.S. Yarris
By
Ecosystems Mission Area, National Wildlife Health Center

Type C botulism in dairy cattle from feed contaminated with a dead cat Type C botulism in dairy cattle from feed contaminated with a dead cat

Four hundred twenty-seven of 441 adult Holstein dairy cattle from a 1,200-cow dairy died over a 1-week period during early spring 1998. Affected animals were from 4 late lactation pens, one of which included the bull string. Signs included weakness, recumbency, watery diarrhea, and death. Eighty animals from the 4 pens were dead approximately 8 hours after the first ill cows were noted...
Authors
F.D. Galey, R. Terra, R. Walker, J. Adaska, M.A. Etchebarne, B. Puschener, R.H. Whitlock, Tonie E. Rocke, D. Willoughby, E. Tor
By
Ecosystems Mission Area, National Wildlife Health Center

Water and sediment characteristics associated with avian botulism outbreaks in wetlands Water and sediment characteristics associated with avian botulism outbreaks in wetlands

Avian botulism kills thousands of waterbirds annually throughout North America, but management efforts to reduce its effects have been hindered because environmental conditions that promote outbreaks are poorly understood. We measured sediment and water variables in 32 pairs of wetlands with and without a current outbreak of avian botulism. Wetlands with botulism outbreaks had greater...
Authors
Tonie E. Rocke, Michael D. Samuel
By
Ecosystems Mission Area, National Wildlife Health Center

Avian botulism Avian botulism

Avian botulism is a paralytic, often fatal, disease of birds that results when they ingest toxin produced by the bacterium, Clostridium botulinum. Seven distinct types of toxin designated by the letters A to G have been identified (Table 38.1). Waterfowl die-offs due to botulism are usually caused by type C toxin; sporadic die-offs among fish-eating birds, such as common loons and gulls...
Authors
Tonie E. Rocke, M. Friend
By
Ecosystems Mission Area, National Wildlife Health Center

Oil Oil

Each year, an average of 14 million gallons of oil from more than 10,000 accidental spills flow into fresh and saltwater environments in and around the United States. Most accidental oil spills occur when oil is transported by tankers or barges, but oil is also spilled during highway, rail, and pipeline transport, and by nontransportation-related facilities, such as refinery, bulk...
Authors
Tonie E. Rocke
By
Ecosystems Mission Area, National Wildlife Health Center

In situ detection of the Clostridium botulinum type C1 toxin gene in wetland sediments with a nested PCR assay In situ detection of the Clostridium botulinum type C1 toxin gene in wetland sediments with a nested PCR assay

A nested PCR was developed for detection of the Clostridium botulinum type C1 toxin gene in sediments collected from wetlands where avian botulism outbreaks had or had not occurred. The C1 toxin gene was detected in 16 of 18 sites, demonstrating both the ubiquitous distribution of C. botulinum type C in wetland sediments and the sensitivity of the detection assay.
Authors
Judy L. Williamson, Tonie E. Rocke, Judd M. Aiken
By
Ecosystems Mission Area, National Wildlife Health Center

Environmental characteristics associated with the occurrence of avian botulism in wetlands of a northern California refuge Environmental characteristics associated with the occurrence of avian botulism in wetlands of a northern California refuge

Avian botulism is an important disease affecting many species of waterbirds in North America, but the environmental conditions that initiate outbreaks are poorly understood. To determine wetland attributes associated with outbreaks of avian botulism in waterbirds at the Sacramento National Wildlife Refuge (SNWR), California, we compared environmental characteristics between wetlands...
Authors
Tonie E. Rocke, Ned H. Euliss, Michael D. Samuel
By
Ecosystems Mission Area, Northern Prairie Wildlife Research Center, National Wildlife Health Center
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