The Winn Feline Foundation is pleased to announce the recent award of five grants funded by the George Sydney and Phyllis Redman Miller Trust. The Trust designated the Winn Foundation as one of its advisor organizations in their desire to “support medical research to investigate the causes, prevention and development of cures for diseases of . . . domestic cats.” Winn President Hilary Helmrich commented, “I am pleased that the expertise of the Winn Foundation and its veterinary consultants has been called upon to assist in the distribution of these funds. We are excited about the proposals that have been funded as a result. This year we awarded $68,730 in grants for two projects on diarrhea in cats, one on asthma, and two on infectious diseases ” feline calicivirus and feline infectious peritonitis.”
A new therapeutic approach for treatment of asthma in cats:
“Hyposensitization using Allergen and CPG motifs for the Treatment of Feline Allergic Asthma” Carol Reinero, DVM, DACVIM. Ph.D., College of Veterinary Medicine, University of Missouri-Columbia. Asthma is one of the most common types of lung disease in cats, and can be debilitating or occasionally fatal. There is no cure for this disease, and treatment often relies on high doses of steroids given for the remainder of a cat’s life. Over time, some cats can no longer be controlled with steroids and can develop life-threatening asthma attacks. In humans with life threatening allergies, a treatment option called rush immunotherapy (RIT) may be employed to attempt to quickly desensitize the patient to the allergen. High doses of the allergen are administered in the hospital under a doctor’s supervision over one to a few days. This procedure causes the body to become resistant to a life-threatening reaction when exposed to the allergen again under natural conditions. Another novel treatment option for asthma is to give CpG motifs, which are components of the bacteria that normally serve to warn the body that it has been invaded by potentially dangerous organisms. The body responds by mounting an immune response that also protects against asthma. The researchers have previously shown in an experimental model of asthma that both of these treatments show promise individually. In this study, they will combine both therapies in their model to determine if RIT combined with CpG motif administration is effective in ameliorating the signs of asthma. The ultimate goal is to determine if this combination therapy is a feasible option for cats with naturally developing asthma.
Investigation of the mechanism for virulence in some feline calicivirus strains:
“Identification of in vivo correlates of differences in virulence between feline calicivirus strains ” what determines the increased virulence of feline calicivirus isolated from cats with severe systemic disease?”, John S. L. Parker, DVM, Ph.D., and Colin R. Parish, Ph.D., Cornell University. In the last few years, highly virulent strains of feline calicivirus (FCV) have caused at least six oubreaks of a newly recognized fatal disease in cats. Although these outbreaks have been limited in extent, there is a real risk that these hypervirulent FCV strains will spread to the general cat population. FCV is highly contagious and may persist in the tonsils of infected cats that recover from the disease.
The goal of this study is to identify markers by which the hypervirulent FCV can be distinguished from the more common, but less virulent FCV strains. Currently, there is no way to distinguish between strains of differing virulence; therefore, the prevalence of hypervirulent FCV in cats cannot be determined and control measures cannot be undertaken to identify and isolate carrier cats. The researchers will examine a large panel of FCV strains in the laboratory for differences in selected genetic, physical, and viral growth properties that correlate with their natural virulence in cats. In preliminary studies, they have found that a hypervirulent FCV strain is more stable at room temperature and grows more rapidly in cell culture than less virulent strains. The researchers believe that these differences will be consistently found in other hypervirulent strains. If they are correct, the researchers will then use genetic techniques to identify the specific genome sequence(s) of FCV responsible for hypervirulence. Their long-term goal is to develop a simple screening assay to identify hypervirulent strains and determine their prevalence in the general cat population, allowing more effective control programs to be developed.
Evaluating treatment options for an emerging intestinal parasite of cats:
“Determination of in vitro Susceptibility of Feline Tritrichomonas Feotus to Nitroimidazoles and Novel Antimicrobials”, Stanley L. Marks, BVSc, PhD, ACVIM,University of California, Davis. Tritrichomonas feotus is a parasite that can cause diarrhea in domestic cats. Infection with T. foetus is characterized by a waxing and waning large bowel diarrhea that occasionally contains fresh blood and mucus. The prevalence at an international cat show was 31% (36 out of 117 cats), with 28 out of 89 catteries affected. Risk factors for protozoal shedding and exacerbation of diarrhea included concurrent infection with Cryptosporidium spp., and cats living in close proximity to each other. There is currently no therapy for elimination of the organism and cats may shed protozoa continually in spite of feces returning to normal consistency. A recent report showed that 57% of cats diagnosed with T. foetus-associated diarrhea were still shedding the organism up to 3 years following diagnosis. Diarrhea persisted for up to 2 years in many cats, despite aggressive antimicrobial administration. Cats infected with T. foetus have failed treatment with recommended and higher doses of conventional antimicrobial drugs including metronidazole, fenbendazole, sulfadimethoxine, furazolidone, tylosin, amoxicillin, and paromomycin. The goal of this study is to evaluate the in vitro susceptibility of feline T. foetus strains to conventional and novel antimicrobial agents in an effort to find a safe and effective treatment for elimination of this organism.
Evaluation of test methods for identification of parasites causing diarrhea in cats:
“Critical Appraisal of Zinc Sulfate Fecal Flotation, Enzyme-linked Immunosorbet Assay, and Immunoflouresence for Diagnosis of Giardia and Crytospodriuium spp, in Naturally Infected Cats”, Stanley L. Marks, BVSc, PhD, ACVIM. University of California, Davis. Diarrhea is an extremely common and clinically significant problem in cats. The intestinal parasites, Giardia and Cryptosporidium, play an important role in many of these cats. The detection of these parasites in fecal samples can be difficult because the organisms can be shed intermittently. Their detection can also be confused with many artifacts such as grass, pollen, and yeast. The need for accurate identification of these parasites in diarrheic cats is important because both organisms can be transmitted to humans. Further, failure to detect these parasites in diarrheic cats often leads to injudicious antibiotic therapy that can exacerbate the diarrhea. Many veterinarians and reference laboratories have resorted to using alternate tests such as ELISA tests that rely upon a reaction between an antibody in the kit and an antigen in the organism to cause a color change that denotes a positive test. However, virtually all of these tests are marketed for use in humans, and their performance characteristics have not been validated in cats. Preliminary studies have shown that many of these tests have unacceptably low sensitivities. This study will evaluate and compare the performance characteristics of 5 ELISA tests with fecal flotation and immunofluorescence in 200 diarrheic cats for the detection of Giardia and Cryptosporidium. These results will assist veterinarians and reference laboratories in the proper selection of diagnostic tests to improve identification of the cause of diarrhea in cats and to facilitate their proper treatment.
Investigation of the inheritance of susceptibility to feline coronavirus infection
“Phase 1 Studies on the Heritability of Resistance/Suspectibility in Feline Enteric Coronavirus Infection in Randomly-bred, Colony Reared, Domestic Cats”, Niels Pedersen, DVM, PhD, and Leslie Lyons, PhD, University of California, Davis. Vaccines have proven infective in protecting cats against either feline enteric coronavirus infection (FECV), or its most serious sequel ” feline infectious peritonitis (FIP). However, preliminary studies indicate that genetic selection for resistance may be possible. Ten to 20% of FECV infected cats will develop strong immunity and no longer shed virus, while an equal proportion will become persistent fecal shedders. The remainder has an intermediate disease course, i.e., alternating between infection, immunity, loss of immunity and reinfection. These patterns of infection and immunity are best explained by genetic differences in susceptibility/resistance. If so, genetic selection for resistance to FECV might be the most effective means to eliminating or minimizing FIP mortality.
This study will use the resources of a large specific pathogen free domestic breeding colony. Accurate records are kept of the matings and progeny of cats in the colony. This study will attempt to create to groups of breeding cats, representing extremes in immunity: 1) cats that develop strong immunity, and 2) cats that remain chronically infected. Cats in each colony with then be bred and kittens tested for their pattern of FECV immunity. Hopefully, progeny will eventually breed true for either resistance or susceptibility. If this can be achieved, future studies will look at the genetic basis for resistance and susceptibility. Hopefully, genetic makers may someday be available to identify breeding cats that have excellent or poor FECV immunity.
For additional information, please write to the Winn Feline Foundation, 1805 Atlantic Avenue, PO Box 1005, Manasquan NJ 08736-0805 or visit the foundation’s website at www.WinnFelineHealth.org.