WebFeline

Press release from Morris Animal Foundation

With a record 90 million cats living in U.S. homes, it might not seem like feline overpopulation could be a problem. But according to Dr. Julie Levy, a Morris Animal Foundation-funded veterinary scientist, an estimated 70 million homeless cats live in the United States. And this number is probably low. The count includes strays that have been lost or abandoned by owners and also feral cats that were born wild and have never lived in a home.

These cats face tough daily conditions and lack veterinary care and vaccines, so they may contract and spread diseases like panleukopenia and respiratory infections. Also, feral cat populations are tough to control. An unspayed female can have multiple litters each year. That adds up quickly to a lot of unwanted cats.

Dr. Levy heads a program at the University of Florida called Operation Catnip, which provides a monthly free spay-and-neuter day for feral cats. This type of program is called trap-neuter-return (TNR), and the theory behind it is that since sterilized cats can’t reproduce, the feral populations will gradually decrease in a humane way. However, TNR programs require funding, community support and many volunteers, including veterinarians, because trapping and transporting cats is costly and labor-intensive. Treating cats in the field would be far more efficient.

With Foundation funding, Dr. Levy tested a sterilization vaccine that targets a hormone in the brain called GnRH. When GnRH is controlled, the cat doesn’t produce estrogen or testosterone and becomes temporarily infertile as a result. Even better, veterinary technicians can easily administer the vaccine by injection in the field.

Dr. Levy was thrilled with the results. Over the two-year study, the vaccine prevented pregnancy in 73 percent of female cats. No other nonsurgical methods have shown such a high success rate with only a single treatment.

This vaccine has the potential to help feline welfare agencies throughout the world control feral cat populations in an inexpensive and humane way. That would mean fewer cats struggling for survival on the streets.

How cats get heartworm

Infection occurs when a mosquito carrying heartworm larvae bites a cat. The larvae enter through the bite and then develop in the tissues.

The immature worms enter a blood vessel and are carried to the arteries in the lung where they cause an inflammatory reaction.

Most worms die at this stage, causing additional inflammation. The worms that progress to the adult stage may live undetected for a couple of years. But, when the adult worms die, the inflammation can be severe enough to cause death.

Although outdoor cats are at a greater risk of being infected with heartworm, both indoor and outdoor cats can become infected.

The average age is fours years – but cases have been reported from nine months to 17 years.

Cats usually have fewer and smaller worms than dogs and the life of the worm is shorter: two to three years verse five to seven in dogs. In addition the percentage of worms that develop into adult stage is 0-25% compared to dogs 40-90%.

Signs of Heartworm
It is very difficult to diagnosis infection by clinical signs alone. Many signs can be non-specific and can look like other diseases. “Signs associated the first stage of heartworm disease, when the heartworms enter a blood vessel and are carried to the pulmonary arteries, are often misdiagnosed as asthma or allergic bronchitis, when in fact they are actually due to a syndrome newly defined as Heartworm Associated R espiratory Disease (HARD).” (From the Heartworm Society)

Acute Signs:

• collapse
• dyspnea
• Convulsions
• diarrhea/vomiting
• blindness
• tachycardia
• syncope
• sudden death

Chronic Signs:

• coughing
• vomiting
• dyspnea
• lethargy
• anorexia
• weight loss
• chylothorax