Day-to-day management demands can make it tempting to take shortcuts with antibiotic dosing.
But the repercussions that come with under- and overdosing cause financial and herd-health problems for your operation, and the industry at large, that cannot be taken lightly.
Avoiding potentially harmful missteps starts with understanding the actual weight of your animals and treating seriously the label of antibiotics such as DRAXXIN® (tulathromycin) Injectable Solution and EXCEDE® (ceftiofur crystalline free acid) Sterile Suspension, said Douglas Hilbig, DVM, beef technical services veterinarian, Zoetis. The labeled dose is what’s optimal for the pathogen being targeted in the species.
Impacts of Underdosing
When it comes to underdosing, the effects go beyond merely one animal and can cause resistance problems that may make recovery more difficult. As an example, Hilbig cited underdosing a 6-week-old calf with only three-fourths of what the label requires. The calf did not receive enough antibiotic to let its immune system take over and control the bacteria in the body. Underdosing may select for resistant bacteria, and later efforts to treat may now be more difficult.
This mistake has ripple effects throughout a herd — not only resistance in that bacteria against the specific antibiotic, but also through the entire class of antibiotics.
Beyond resistance, underdosing can carry a significant financial burden.
“By underdosing the calf, I could save $8,” Dr. Hilbig said. “And if I lose an $800 calf because I did that, it’s not good math.”
Impacts of Overdosing
Overdosing equates to essentially giving money away, especially with new products, as they are low-dose products. Overdosing means giving an animal more than it needs and spending more than necessary to do so.
And while overdosing might not create resistance issues, it needlessly extends withdrawal times and makes management more difficult. Ultimately, a producer doesn’t know when an overdosed animal will have the antibiotic out of its system.
“If you overdose by 25%, that doesn’t mean a 25% increase in withdrawal,” Dr. Hilbig said. “It could actually double it. You have to talk to your veterinarian about how this overdose has affected withdrawal.”
Importance of Accurate Bodyweight
If at all possible, put a scale under the chute or use a group scale, Dr. Hilbig said. It not only corrects dosing issues but also provides useful information and benefits an operation beyond antibiotic use.
Learn more about effective and responsible antibiotic use by watching this video.
IMPORTANT SAFETY INFORMATION FOR EXCEDE: People with known hypersensitivity to penicillin or cephalosporins should avoid exposure to EXCEDE. EXCEDE is contraindicated in animals with known allergy to ceftiofur or to the ß-lactam group (penicillins and cephalosporins) of antimicrobials. Inadvertent intra-arterial injection is possible and fatal. Do not use in calves to be processed for veal. Pre-slaughter withdrawal time is 13 days following the last dose. See full Prescribing Information.