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A fungal infection that is killing amphibians around the world acts by disrupting the flow of electrolytes across their skin, ultimately causing heart failure. The discovery is helping to raise hopes that a treatment for the infection could one day be given to amphibians in the wild. Batrachochytrium dendrobatidis, a kind of chytrid fungus that causes the skin disease chytridiomycosis in amphibians, was likely spread around the world by the South African clawed frog (Xenopus laevis) in the 1930s and 1940s, when the frog was widely used as a pregnancy test. A pregnant woman's urine, injected under the frog's skin, would contain sufficient hormones to make the animal ovulate. But although the South African clawed frog seems to have immunity to the disease, many other amphibians are not so lucky. According to one study led by chytrid expert Karen Lips of the University of Maryland in College Park, chytridiomycosis can kill 80% of amphibians in one year in an area with cool, moist conditions.1 Until now, no one was sure exactly how the fungus killed its victim; some researchers thought that it might secrete a poison. Jamie Voyles, a disease ecologist at James Cook University in Townsville, Queensland, Australia, and colleagues exposed Australian green tree frogs (Litoria caerulea) to the fungus, and have now worked out its deadly mode of attack. Voyles and colleagues monitored the progression of the infection, took blood and urine samples and measured electrolyte flow across skin samples. They found that levels of two ions — potassium and sodium — were greatly reduced in infected frogs, and that the ability to move these ions back and forth across the animals' skin had been greatly impaired. "Frog skin is really unique because it is permeable to water but it must maintain proper concentrations of these [electrolyte] ions," says Voyles. In infected frogs, "the electrolyte balance is all out of whack". The low potassium levels, in particular, were probably responsible for a breakdown of the electrical regulation of the heart, and the frogs ultimately died because their hearts stopped. The work is reported in Science2. Rich solution
The team found that an electrolyte-rich solution, similar to sports drinks but more concentrated, delayed death in infected frogs. But it couldn't cure them. "Because the skin is damaged, we can't really keep them from dying unless we fix the problem in the skin," says Voyles. Although captive frogs can be bathed in an antifungal medicine to rid them of their infection, there is no easy way to treat the hundreds of species of wild amphibians at risk of being wiped out by the fungus. Voyles's work is just one piece of research that might someday lead to a treatment that could be deployed in the wild. Geneticist Erica Rosenblum of the University of Idaho in Moscow is looking at gene expression in both the fungus and the host to determine what makes the fungus so lethal — and why amphibian immune systems don't seem to be aware of the infection.3 "Jamie has found that their osmotic regulation is all screwed up, they are essentially having heart attacks," she says. "Mine is an earlier question: why don't they have an immune response?" One possible treatment is being pursued by Reid Harris, a microbial ecologist at James Madison University in Harrisonburg, Virginia. He has found that at least some species of amphibians have beneficial bacteria on their skin that produce a protective antifungal agent.4 He is looking into the possibility of adding more of these bacteria to the soil in ecosystems where vulnerable amphibians live, to boost their natural defences. "People are already doing this in their gardens and larger-scale agricultural applications as well," he says. Harris would first like to try the technique on populations of frogs in captivity — so-called survival assurance colonies held in zoos and other institutions awaiting the day when they can be safely returned to the wild. Despite all these advances, Lips says that she has seen too many frog populations destroyed by the fungus to retain her optimism about saving what is left. "I don't know that there is enough money going to the right labs quickly enough to make a difference," she says. "More governments and NGOs need to step up. I mean, we are losing half the amphibians on the planet. And throwing amphibians into zoos is a short-term solution. It doesn't solve any problems." References Lips, K. R., et al. Proc. Natl. Acad. Sci. USA 103, 3165-3170 2006 | Article | PubMed | ChemPort |
Voyles, J. et al. Science 326, 582-585 (2009).
Rosenblum, E. B. et al. PLoS ONE 4, e6494 (2009).
Harris, R. N., Lauer, A., Simon, M. A., Banning, J. L. & Alford, R. A. Dis. Aquat. Organisms 83, 11-16 (2009). (http://www.freerepublic.com/focus/f-news/2369809/posts))
The City of Manhattan and Bartlett and West Engineers will host an Open House for the Tecumseh/Quiveria Stormwater Improvements Project February 17 from 4:00 p.m. to 6:00 p.m. in the City Commission Room, City Hall, 1101 Poyntz Avenue. The public and interested stakeholders are encouraged to attend. City staff and Bartlett and West representatives can answer questions and take input for the project. For more information about the project, contact Brian Johnson, Principal Civil Engineer, at johnsonb@ci.manhattan.ks.us or 587-2455.
Your children will have enjoy the WILDest adventures and hands-on learning experiences while spending the summer at Sunset Zoo! Download the Summer Club Packet! 2010 Summer Zoo Club Packet
The City of Manhattan will host a public input session for the Downtown Entertainment District on February 11 from 7:00 p.m. to 8:00 p.m. in the City Commission Room, City Hall, 1101 Poyntz Ave. The public input session will be an opportunity for HWS Consulting Group, Bowman, Bowman, Novick Architects, and the City of Manhattan to share and obtain information on current plans for the project, with focus on design concepts for the proposed one-acre park and the pedestrian underpass between the district and the historic Union Pacific Depot. The event will be an open-house format. Attendees are invited to circulate the information stations and provide input to development team members. At 8:00 p.m., there will be a summary of presentations providing input they received during the open-house session.
Prairie Dog Preschool, Kinder Cubs, New ZOOfari Tails, ZOOrific Birthday Parties, Vista Kids' Night Out, Z.O.O. Crew, Junior ZooKeeper orientation, Docent training and more await you, your family, and friends at Sunset Zoo! Download the 2010 Winter/Spring Sunset Zoo Registration below. You are one click away from wintertime and spring adventure! 2010 Winter/Spring Sunset Zoo Registration
The City of Manhattan would like to remind citizens of the requirements of the snow and ice removal ordinance (Section 30-71 of the City’s Code of Ordinances). This ordinance states that snow and ice are to be removed from sidewalks within 36 hours of the end of a snowfall or ice accumulation. Failure to do so may result in removal by the City, with the cost of that removal being charged to the abutting property owner. Where sidewalks are covered in ice, application of ice melt, fertilizer or similar de-icing agents may be used. Brad Claussen, Building Official, says that those enforcing the ordinance understand that some sidewalks may be blocked by windrows from snowplows. “In those cases, please do the best that you are able in removing the snow and making travel safe for pedestrians,” says Claussen. “Also, if you are aware of a neighbor that is in need of assistance, please help out as you can.” Citizens in need of assistance with snow removal, or those willing to volunteer to help others should contact Nick Arena, 785-587-4588. To view full ordinance or to report a suspected code violation via email, visit the City’s Web site, www.ci.manhattan.ks.us. Contact Code Services with any additional questions at 785-587-4506.
Your children will have enjoy the WILDest adventures and hands-on learning experiences while spending the summer at Sunset Zoo! Download the Summer Club Packet! 2010 Summer Zoo Club Packet
Prairie Dog Preschool, Kinder Cubs, New ZOOfari Tails, ZOOrific Birthday Parties, Vista Kids' Night Out, Z.O.O. Crew, Junior ZooKeeper orientation, Docent training and more await you, your family, and friends at Sunset Zoo! Download the 2010 Winter/Spring Sunset Zoo Registration below. You are one click away from wintertime and spring adventure! 2010 Winter/Spring Sunset Zoo Registration
The City of Manhattan Public Works Department, in conjunction with the Kansas Department of Water Resources, will be conducting a project to update stream topology information. Five different watershed stream ways will be surveyed over next few months: CiCo Tributary: Dickens Avenue south to Wildcat Creek
Little Kitten Creek: Colbert Hills south to Wildcat Creek
Rolling Hills: Amherst Avenue north to Wildcat Creek
Nevada-Montana: Dickens Avenue south to Wildcat Creek
Wildcat Creek Tributary: Keats Park south east to Kansas River The collected information will be used to better model flood events that could impact Manhattan. The project will also allow FEMA to more accurately model their flood hazard maps for Manhattan and Riley County.
Beginning this month and continuing through March 2010, city employees will be conducting stream cross-section surveys at defined points along the surveyed waterways, and at times will be accessing private property. Please contact Rob Ott, City Engineer, with questions at 785-587-2415.
Your children will have enjoy the WILDest adventures and hands-on learning experiences while spending the summer at Sunset Zoo! Download the Summer Club Packet! 2010 Summer Zoo Club Packet
Prairie Dog Preschool, Kinder Cubs, New ZOOfari Tails, ZOOrific Birthday Parties, Vista Kids' Night Out, Z.O.O. Crew, Junior ZooKeeper orientation, Docent training and more await you, your family, and friends at Sunset Zoo! Download the 2010 Winter/Spring Sunset Zoo Registration below. You are one click away from wintertime and spring adventure! 2010 Winter/Spring Sunset Zoo Registration
Owners of exotic animals like reptiles and birds need to be aware of illnesses that can affect both their pet and humans, according to a Kansas State University veterinarian. Gary West, assistant professor of zoological medicine in K-State's College of Veterinary Medicine, said exotic animals can make fun and interesting pets, but there are many health factors to consider before owning one. West said common exotic pets are ferrets, rabbits, guinea pigs, reptiles and birds. He recommended several of these animals as good pets, including cockatiels, guinea pigs, rabbits, bearded dragons, corn snakes, blue-tongued skinks, some species of tarantulas, freshwater tropical fish and some tortoises. Owning an exotic pet is different from owning pets like dogs and cats. Some exotic pets have specialized needs, such as lizards that require an ultraviolet light for basking, live insects for food or other whole prey items, West said. "Many of our diets and health care are very advanced for dogs, which have been domesticated for a long time," he said. "Many exotic pets are non-domestic, and although many advances have been made, there are still things we are learning about them." West said there are fad exotic animals every few years that can be challenging to own, such as a kinkajou. West said this South American animal is related to the raccoon and typically does not make a good pet because of special environmental requirements and that it can bite. He said all exotic animals have specific needs and requirements, and it is important that the pet owner become educated about the animal before purchasing it. He said the best way to keep an exotic pet healthy is to know what it requires to stay healthy and thrive. Exotic animals can carry diseases, West said. Reptiles are commonly known to be at risk of carrying salmonella, and there have been reports of other diseases, including chlamydia, in pet birds. Rabies also is a concern for mammals if they go outdoors. However, unlike dogs and cats, exotic pets like reptiles can carry diseases like salmonella without getting sick -- but that puts other animals and humans at risk. West said after handling an exotic pet, people should wash their hands immediately. He also said reptiles should not be allowed to roam free, they should not be allowed in the kitchen or around people who are eating, and owners should disinfect surfaces where reptiles have been. Additionally, the U.S. Centers for Disease Control and Prevention recommends that reptiles not be kept in homes with children younger than 5 years or with immunocompromised people, he said. West said typically there are no signs or symptoms to tell if an exotic animal is a carrier of salmonella or other diseases, though the animal could infect other pets. To keep other pets from getting the diseases, West said the same principles for humans apply. Other animals should not come into direct contact with the exotic pet, for mutual benefit, and the animals should keep away from each other's food and water bowls. Some exotic animals do not like much handling, noise or strangers, and agitating the animal puts the owner at risk for bites and scratches. Bite wounds can become infected with bacteria from the pet's mouth and should be examined by a doctor. Additionally, injuries are fairly common in small pets, so owners should be careful when the animal is around larger animals like dogs or around young children, West said. "We see many cases where the family cat or dog injures or bites the exotic pet, which are often can be life-threatening wounds," he said. He said owners should not impulse-buy pets, especially exotic animals. People also should buy from a good source who is knowledgeable about husbandry and care, and the source should also be able to recommend good products and guarantee that the animal is healthy. West also said to see if the source is selling species that make good pets. He said there are many animals that should not be pets, such as monkeys. Primates make bad pets for several reasons, he said, including because they can carry diseases that are transmissible to humans. "Wildlife do not make good pets, and it is illegal and irresponsible to take a baby animal from the wild and raise it or make a pet out of it," West said. "You are not helping it." West said owning a pet can be good for children as a way to learn patience and responsibility, and all pets can be great companions and even stress relievers. "Watching your fish or learning more about these fascinating creatures can be great hobbies for children and adults," he said. "Observing and learning about their behavior can be very interesting and help foster an interest and love for animals and wildlife." From an article appearing online at http://kstatenews.org/?p=1644. Used with permission of the Dr. Gary West.
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