LAKE TOWNSHIP – A cow on a Lake Township farm has been diagnosed with rabies but it posed no danger to the public, authorities said.

The farm has been placed under quarantine, a Pennsylvania Department of Agriculture Press Secretary Shannon Powers said Monday.

The farmer contacted a veterinarian to look at the adult beef cow after it began “mooing abnormally’’ and was attacking other animals in the herd and the owner, Powers said.

After being examined by the vet, it was decided the cow needed to be euthanized. Its carcass was taken to the Agriculture Department’s Harrisburg laboratory where it tested positive for rabies, Powers said. To test the cow for rabies it had to be killed, she added.

“We typically do not give out the location of quarantined farms, given that rabies is widespread throughout the state, and this particular instance poses no public health risk,’’ she said. “As far as prevalence goes, there were only three cases of livestock in the state last year that were found to be rabid, and it’s unusual for a cow to be added.’’

Neither the farmer nor the veterinarian have shown signs of rabies but are undergoing treatment as a precaution, Powers said.

The 19 other head of cattle are receiving rabies treatment and will be quarantined at the farm for 120 days. It wasn’t known how the cow contracted rabies but likely was from direct contact with another animal.

“It is possible, but extremely unlikely, that cattle could contract rabies through their feed or water trough,’’ Powers said. “In fact, rabid animals are afraid of water. The virus shed in saliva is viable for an extremely short period of time, and would need to enter the exposed animal’s bloodstream directly – usually through an open wound. Open feed troughs can attract wild animals, which then bite livestock – that’s the most likely scenario.’’

Only mammals get rabies, she said. There is no rabies in birds, lizards or other non-mammalian animals.

“Raccoons are primary carriers of rabies and so are cats,’’ Powers said. Pennsylvania law requires all cats and dogs three months of age and older to be vaccinated against rabies.

Human interaction with rabies in northwestern Pennsylvania is much lower than other parts of the state.

“The northern tier doesn’t get a lot of rabies,’’ she said. “You find that interaction in the denser populations of the state where there are cities and towns.’’

While not required by state or federal law, the Agriculture Department strongly recommends that show cattle – those exhibited at fairs and cattle shows – are vaccinated for rabies.

All cattle at the PA Farm Show, All-American Dairy Show, and Keystone International Livestock Show are vaccinated for rabies.

“This is an important preventative measure for public health, given the interaction between the public and cattle at such events,’’ Powers said “In the unlikely event that a cow were to exhibit signs of rabies after a show, it would be virtually impossible to trace who had been exposed.’’