Many Texans rely upon the weather for a variety of reasons. From crops to cattle, Texans are often at the mercy of Mother Nature. Although droughts can have a dire impact on animal health, floods can contribute to widespread issues among animal owners. Excessive rainfall can contribute to mosquito-borne diseases, toxic plants, dermatologic conditions, and many other diseases. The Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL) offers testing and diagnostic consultations to assist animal owners and practitioners with many issues contributed to flooding. This post is the first in a series that cover the various animal health concerns contributed to flooding.
Here are some of the potential animal disease concerns TVMDL encourages animal owners and practitioners to be aware of during periods of excessive rain.
Transmission of the spirochetes causing leptospirosis increases when environmental conditions favor their survival. Wet conditions increase the potential for leptospirosis exposure. Leptospirosis affects a wide range of animals from livestock, horses, and dogs to wildlife. Once infected, the animal will shed spirochetes in urine for various periods of time; and therefore, contaminate the environment and provide a source of infection for other animals.
The clinical signs of leptospirosis vary and are nonspecific, according to the Centers for Disease Control and Prevention (CDC). Some clinical signs in canines include: fever, vomiting, abdominal pain, diarrhea, refusal to eat, severe weakness and depression, stiffness, severe muscle pain and, infertility in breeding dogs. Generally, younger animals are more seriously affected than older animals.
Various species of wildlife (rodents, skunks, raccoons and other small mammals) serve as maintenance hosts for leptospirosis. Therefore even “city dogs” that are allowed access to parks, nature trails ,and even the backyard, where wet areas can exist, are at risk of being exposed to leptospirosis Leptospirosis can be the cause of reproductive problems, as well as other medical conditions in livestock and horses. Veterinarians can work with TVMDL to perform tests to determine if leptospirosis is the cause of an animal’s illness.
TVMDL performs a microscopic agglutination test (MAT) and polymerase chain reaction (PCR) test for leptospirosis. The MAT can provide titers that indicate infection in the presence of compatible clinical signs. The PCR test can detect the presence of the organism in clinical specimens, which helps differentiate an infected animal from one that may be showing vaccine titers.
Herds can be vaccinated to protect against clostridial diseases such as Blackleg, Malignant Edema, Red Water disease and other clostridial infections. Spores from the bacteria that cause these diseases can reside in the soil for a few months or even years. Disturbance of the soil can expose the spores and make them more accessible to grazing animals. There can be an increase in clostridial infections in years of high rainfall and flooding. The spores can be spread to new pastures by flood water and run-off.
TVMDL’s bacteriology sections can perform a Clostridium fluorescent antibody (FA) assay on bovine, ovine, and cervid samples. This acute, highly fatal disease of cattle and sheep is caused by the Clostridium chauvoei bacteria and is one of the more common clostridial infections. The bacterial spores may be found on farms after flooding where it was not previously known to exist. This is also true for the other clostridial diseases. Signs of infection include emphysematous swelling, commonly affecting heavy muscles (clostridial myositis).
Commonly contracted by beef breeds, cattle 6-24 months old are the most susceptible, but disease may occur in cattle as young as 6-week-old and as old as 10-12 years old. In sheep, Blackleg often follows a wound infection following procedures such as shearing, docking or castration. Onset can be sudden, with large, hot and painful lesions; death can occur within 12-48 hours. For more information on testing, click here.
Anthrax is endemic in some areas of Texas and is caused by the spore forming bacterium Bacillus anthracis. Anthrax cases are often associated with periods of weather extremes. Cases may increase in years of high rainfall and flooding, especially when preceded by a drought; floodwaters may carry spores to new areas.
Anthrax should be considered in cases of sudden death in livestock, especially when dark or tarlike blood exudes from all orifices. If there is good reason to suspect Anthrax, the carcass should not be opened. A cotton or Dacron tipped swab can be soaked in the bloody discharge, placed in a red top tube and submitted to the diagnostic laboratory. TVMDL is equipped with capabilities for properly, and safely, testing the sample for anthrax.
Confirmed cases of Anthrax are reported to the Texas Animal Health Commission. Livestock owners should work with their veterinarian and the commission concerning vaccination protocols and proper disposal of infected carcasses. Laboratory testing is needed to confirm a suspected case of Anthrax.
An inflammation of the mammary gland, mastitis is usually due to infection by bacterial pathogens. Mastitis outbreaks are an issue in flooded areas and areas that have been very wet for prolonged periods. The wet, muddy conditions contaminate the teats and predispose the udder to mastitis.
Preparing animals for milking is important to preventing mastitis. Clean and dry the teats; signs of flakes, clots, watery milk, or hard and swollen quarters at milking are signs of mastitis.
Proper diagnosis and treatment of mastitis is important in an attempt to preserve as much functional mammary tissue as possible. Bacteriology culture and sensitivity results are used to select the proper antibiotic for the treatment of mastitis.
For more information on TVMDL’s test offerings, visit tvmdl.tamu.edu or call and schedule a consultation with one of TVMDL’s veterinary diagnosticians in College Station at 1.888.646.5623 or in Amarillo at 1.888.646.5624.
Download this flood series of posts in a comprehensive document here.
Click here to view potential insect-borne disease concerns for livestock owners during floods.