Cattle and Salmonella

Around the world, 2,300 varieties of salmonella exist, many of which pass from cattle to human with ease. Salmonella typhimurium DT104 poses a serious threat because it shows high antibiotic resistance, according to the University of California School of Veterinary Medicine. In cattle, both calves and adults can suffer infection. Many cows live as carriers, actively shedding the salmonella each time they eliminate.

  1. Transmission and Occurrence

    • Approximately 38 percent of all feed lots and 16 to 73 percent of dairy cow operations within the U.S. show salmonella infestations, according to the American Academy of Veterinary Pharmacology &Therapeutics. Cattle become infected with salmonella when they are exposed to a carrier animal, through contaminated feed that has been irrigated or fertilized with fecal matter containing salmonella. and through contact with rodents, mammals and birds. Humans can also transmit salmonella to cows if infected when handling the cow.

    Rendering

    • Livestock that die of salmonella poisoning are normally rendered. Rendering is the process of turning the dead carcass into animal food. Most farming, dairy and livestock operations render their dead cattle. Unfortunately, rendering often does not kill all of the salmonella which enables it to infect the food. By some estimates, 5 to 20 percent of all feed given to dairy cows contains salmonella, according to the American Academy of Veterinary Pharmacology &Therapeutics.

    Danger of Infection

    • Healthy cattle that consume feed infected with salmonella are rarely affected. If the feed becomes moist, however, the salmonella quickly multiplies to such high levels that the cow's immune system is unable to combat it and the animal succumbs. This can result in the entire herd becoming infected or only those who are weak, old or young.

    Prevention/Solution

    • Repetitive testing of cattle or testing of new cattle can help detect silent carriers within a herd. Never allow feed to become moist. Keep the area where cattle are housed free of accumulated fecal matter. Keep rodents and birds out of livestock feed to reduce the possibility of salmonella exposure, according to Michigan State University. Always wear disposable boots when entering a dairy yard to prevent outside fecal matter from coming into contact with the herd. When using a loader bucket, do not use the same one to pick up manure and also feed. Cross contamination can easily occur. Always maintain clean feed and water buckets.

    Zoonotic

    • Salmonella is a zoonotic disease, which means it is easily transmitted from livestock to humans. Always wash your hands after being around cattle. Keep your hands away from your face and mouth when handling livestock. Never eat or drink near livestock.

    Treatment

    • A veterinarian will administer fluids and electrolytes to the infected cow. Antimicrobial drugs and non-steroidal anti-inflammatory drugs will often be prescribed. Antibiotics are rarely used in the treatment of salmonella in cattle due to the danger of developing antibiotic resistant strains that can pose a serious danger to humans who contract salmonella. If antibiotics cannot be effectively used on humans who contract salmonella, then the survival rate would be quite low. Vaccination of pregnant cows can help prevent calves from contracting salmonella.