Among livestock species, cattle are among the most likely to contract rabies. The usual means of transmission of this deadly disease is via a bite from a rabid racoon, fox or other midsize mammal. A less common mode involves the saliva from an infected animal entering the bovine's skin through a wound or mucous membranes.
Signs of Rabies
The closer the bite is to the head, the sooner signs of rabies appear. A cow bitten on the nose may show signs within weeks, while an animal bitten on a rear leg might not become symptomatic for months. Early signs of rabies are subtle and often mimic other diseases. Affected dairy cows might eat less and produce less milk, but only after the disease advances do feed consumption and milk output drop a great deal.
Behavioral changes occur -- passive animals become aggressive and ill-tempered bovines appear friendly. Other changes include hypersalivation, inability to swallow, tongue protrusion, unsteady gait, straining to urinate and defecate, and constant vocalization. Swallowing issues are often mistaken for choke, so a farmer or vet might put his hands into the animal's mouth to remove the obstruction -- thus exposing himself to the virus. Always call your veterinarian to examine an animal displaying any neurological symptoms. Isolate an animal showing neurological symptoms from any other livestock or pets.
The End Is Near
Infected cattle generally die within a week of showing symptoms. An affected animal will go down, unable to get up. If you're dealing with a sick cow with vague symptoms, do not shoot the bovine in the head to end its misery. If rabies is suspected, the intact head of the cow must be sent to the state veterinary laboratory for testing. If the result is positive, anyone in close contact with the animal must receive a series of rabies vaccinations.
While state laws generally mandate vaccinating dogs against rabies, that's not true for livestock in general. Your state might recommend a vaccination protocol for cattle, but it's likely to mandate rabies inoculation only for those bovines exposed to the public, such as animals in petting zoos or on exhibition at fairs or similar events. Certainly, if you have a small herd, it's worth the expense of having your cattle vaccinated against rabies. Only a licensed veterinarian can inoculate animals against this fatal virus.