Springtime is often when calves get their first vaccinations. It’s also their first exposure to high endotoxin loads.
Protecting calves from disease often begins with vaccinating young calves as they transition to grass or are branded. These vaccines contain a combination of Gram-negative bacteria, which commonly include Mannheimia haemolytica, Pasteurella multocida, and Histophilus somni, among others. Excessive endotoxin levels can be dangerous.
In a perfect world, cow-calf producers would administer one vaccine at a time, spacing them out to avoid endotoxin stacking. However, that is generally not the case due to the necessity of time management.
“When we talk about stress on these calves, there’s acute stress and chronic stress,” says Dr. Brett Terhaar, beef technical consultant for Elanco. “Branding or turnout to grass vaccination of young calves (60 days) is a time of acute, short-term stress for calves. We often administer vaccines, separate calves from cows for a few hours, and some calves may undergo surgery or castration, but the risk of stress-related respiratory diseases is low.”
After administering Gram-negative vaccinations, calves may experience a post-vaccination reaction due to high endotoxin levels. This is commonly called a “sweat,” and symptoms can resemble those of pneumonia, as the clinical signs of a heavy endotoxin load often mimic respiratory diseases.
“Calves are sensitive to endotoxin, but weight is a significant dilutional factor. If a vaccine protocol has a high endotoxin load, a 60-day-old, 200-pound calf will be more negatively affected than a 500-pound calf, which will then be more negatively affected than a 1,000-pound animal,” says Terhaar.
A heavy endotoxin load can cause fever, hypotension, blood vessel damage, shock, and even death.
“Anytime I see more than one calf have a severe negative reaction to a vaccine, my antennas go up. If I see multiple deaths, I start looking at vaccination protocols,” Terhaar says. “Some vaccines provide a higher dose of endotoxins than others. That’s where a product, like Elanco’s NEW NUPLURAÒ PH+5 really shines.”
Endotoxins are inherent in Gram-negative bacteria. The production of vaccines involves growing bacteria in an extensive fermentation system where bacteria continually grow and die. When bacteria die, if their cell walls are disrupted, whether naturally or through the manufacturing process, free endotoxin are released.
For example, a vaccine protocol can deliver several Gram-negative bacteria, including Histophilus somni, Mannheimia haemolytica, Pasteurella multocida, and Salmonella, will contain a significant amount of endotoxin.
Many Gram-negative bacterial vaccines deliver as many as 100,000 (+/- 20,000) endotoxin units per vaccine dose. In comparison, NUPLURA PH+5 does not significantly contribute to the endotoxin load, containing only about 1,500 endotoxin units per dose.
If you use three vaccines that each contain 100,000 endotoxin units, 300,000 endotoxin units are being delivered to that calf, and when numbers this high are delivered to a small calf, the potential for adverse events increases,” notes Terhaar.
Due to the unique manufacturing process for NUPLURA PH+5, the endotoxin load remains consistently lower than that of other Gram-negative bacterial vaccines. A 5-way viral vaccine, NUPLURA PH+5 includes protection against Mannheimia haemolytica bacteria.
“With NUPLURA, we are not giving the calf the entire bacteria. We are administering a vaccine composed of the outer portion of the bacteria, excluding the cell wall, which reduces the endotoxin units delivered to the calf. I like to think of the bacteria like a basketball. We aren’t making the vaccine from the complete ball. We’re shaving the dimples off and providing the calf with the dimples instead of the cell wall, which contains the majority of the endotoxin load.”
Terhaar recommends walking through the herd approximately 20 minutes after vaccinating to assess calves for respiratory distress or allergic reactions.
Although the risk of anaphylaxis is low, calves can, on rare occasions, experience an allergic reaction related to vaccines.
Cow-calf producers should closely monitor calves following vaccine administration and keep epinephrine on hand in case of an allergic reaction.
Other tips for maximizing your spring vaccination program include:
- Be careful to ensure that bacterial vaccines are not stored in freezing conditions. If gram-negative vaccines freeze, the water inside the cell can form sharp ice crystals that break the cell apart and release free endotoxins.
- Carefully invert vaccines to mix and avoid settling. Shaking until bubbles or foam form may increase the release of endotoxin.
For all vaccine products: The label contains complete use information, including cautions and warnings. Always read, understand and follow the label and use directions.
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