From floods to droughts, 2011’s weather extremes can create unexpected health problems in your cattle herd
With droughts in the South and flooding in other areas this summer, there will likely be new health challenges for cattle this fall. As outside cattle arrive to your operation, whether to be placed on feed or as new additions to the breeding herd, they may bring new and unexpected diseases.
One defense against these diseases is a thorough vaccination program that will boost herd immunity, says Dan Goehl, a veterinarian in Canton, Mo.
In addition to vaccinations, biosecurity protocols to keep new additions separate from existing cattle can help limit the spread of diseases. Also, knowing where the cattle you are bringing in came from can help you and your veterinarian develop a vaccination program to boost immunity.
Ready to infect. Cattle that have been on flooded pastures could have diseases that lie dormant and that wait for rain to reactivate.
"Blackleg, or Clostridium chauvoei, is a soilborne bacterium, and any disturbance to the soil, such as a flood, may increase the exposure of cattle to the bacterium," says Tom Troxel, a beef specialist at the University of Arkansas. Blackleg symptoms include lameness, depression and fever, and often result in sudden death.
"Blackleg vaccine is one of the cheapest vaccines to purchase for cattle," Troxel says. "It is recommended that cows and calves be vaccinated if flooding is an issue at your farm."
Another disease, Lepto hardjo-bovis, is easily spread in flooded areas where there is standing water. Lepto hardjo-bovis is transmitted through membranes of the eyes, nose, mouth and skin when uninfected animals come in contact with the urine of infected animals directly or through contaminated water.
Jon Seeger, DVM, veterinary operations, Pfizer Animal Health, says many producers may not realize their herds are infected with Lepto hardjo-bovis, especially if the disease has been present for a long period of time.
"When left unvaccinated, cattle are vulnerable to hardjo-bovis infection when given access to streams and stagnant water, or when pastures and facilities are exposed to raccoons, opossums or rodents," says Joe Campbell, senior professional services veterinarian, Boehringer Ingelheim Vetmedica, Inc.
For fed and feeder cattle, bovine respiratory disease (BRD) could be a bigger issue this fall as cattle coming from weather-challenged areas may have weaker immune systems.
In the southern High Plains, the fall calf run has already occurred as drought forced cattle into feedyards earlier than most expected. For stockers and feeders in the Midwest and other regions, however, receiving cattle could present some unique challenges depending on the source of origin. Southern feedyards are learning that cattle from drought areas are coming into the yards with lower nutrition levels and weakened immune systems. Administering vaccinations and boosters according to label direction and at the proper time is an important part of boosting the calves’ immunity.
Nutrition is also a key component in the animal health equation, so consult with a veterinarian and nutritionist to help the cattle you receive adjust to the new diet.
Optimizing health. While cows and heavier weight cattle are also susceptible to new disease pressures, lighter weight and newly weaned calves may have additional challenges even in average weather years.
"Young, light, freshly weaned calves represent a unique set of health management challenges. This class of cattle is at risk for respiratory disease due to high stress associated with this stage of production," Goehl says. "Risk of pathogen [disease] exposure is greatly increased if animals from multiple sources are combined in one location for growing. This decrease in performance due to illness at weaning may haunt the calf until he is harvested, decreasing profits for each stage of production."
Goehl adds that there is no magical silver bullet that will keep all animals healthy. Vaccinations are an important tool, "but do not fall into the trap of expecting them to overcome management shortcomings. The most important thing that can be done is to do all of the little things correctly," he says.
Accurate processing records are crucial in order to maintain quality controls and evaluate product performance. Goehl says you should record when calves receive initial vaccinations and boosters.
"The administration of many products induces a withdrawal time on each set of calves and proper
records make compliance with withdrawal times possible," Goehl says. It also helps later when evaluating the effectiveness of vaccines.
Initial processing timing and technique is critical because stressed animals do not generate an adequate immune response; care should be taken to avoid undue stress. Processing should be calm, quiet and efficient to minimize animal stress.
"The goal is to work the animals as efficiently as possible—not as fast as possible. The quality of each procedure performed is more important than the speed at which it is performed," Goehl says. "Improperly administered products do not prevent disease; thus, we may end up getting that calf up again for treatment, which in the long run adds additional time we must spend on each calf."
"The highest-quality vaccine available can be useless if not handled and administered properly," says Ron Gill, Texas AgriLife Extension livestock specialist. He offers these tips for effective vaccination procedures:
- Determine target pathogens
- Select the most effective vaccine available
- Prevent exposure of vaccine to heat and light
- Use only sterile needles and syringes
- Always draw from a bottle with a sterile needle
- Use quality syringes
- Use proper needle size
- Inspect and maintain all working components
- Administer the proper dose in the recommended route: intramuscular, subcutaneous or intranasal
- Change needles often to reduce tissue irritation
- Always follow label directions
- Booster all vaccines when the label requires it
- Leave vaccines in direct sunlight or UV light
- Leave vaccines refrigerated
- Place a used needle in a bottle of vaccine
- Place vaccine in the hip or upper round of the animal