With so much depending on the outcome, the choice of which antibiotic to use on their animals, or if one is necessary at all, is one of the most difficult decisions facing ranchers and feedlot owners.
One article cannot hope to clarify every combination but a strategy that combines solid animal management knowledge and veterinarian advice should offer the best route.
By reading the label, producers can find out which products have been cleared for which diseases.
This provides information on what types of diseases and what organ systems the antibiotic will get into.
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Most antibiotics, especially the new ones, will need a prescription from a veterinarian. This ensures producers are aware of the conditions it is used for, dosage, method of administration and withdrawal times.
Veterinarians base their decisions on whether to provide antibiotics on several factors.
First, are antibiotics necessary or will convalescence be enough? If there is no bacterial infection or expected, antibiotics may be unnecessary, such as in cases of viral infections. On large mature cattle or feedlot animals, the meat withdrawal times need to be considered.
If a condition becomes chronic, slaughter may be an option.
If daily care is better, can we accomplish that? Or is the next best long-acting product the way to go?
Other considerations are the ease of use with a syringe (especially important in winter), dosage amount, safety of the drug, means of administration (subcutaneous, oral, intravenous) and cost of the product per treatment per day.
The cost per day is really the best way to compare treatment costs. The longer-acting products cost more because they last longer. The upside is less labour and subsequently less handling and lower stress on the cattle.
This may be nullified if other procedures or painkillers must be given on a daily basis.
The main decision veterinarians and farmers make is based on the conditions, the organ system involved and the causative bacteria. From these three main things, the most appropriate first, second and third choice of treatment are made. These three choices might be made in a different order on different farms based on farmer preference, previous results or current research results.
There is almost never a simple one choice product.
A few antibiotics are called broad spectrum, meaning they work against a wide array of bacteria in different organ systems. The older sulphonimides, as well as newer drugs like Nuflor, Resflor or Excenel, are fairly broad in their effect. Other drugs are for specific treatments, such as for pneumonia. The macrolide antibiotics are a class of drugs that get into the lungs.
Drugs such as Zuprevo, Draxxin, Zactran and Micotil are all macrolides and are used primarily for bacterial pneumonia and only a few other things.
Veterinarians may prescribe them for other specific problems, such as seminal vesiculitis in young bulls, but there will never be a label claim against these oddball infections. A veterinarians’ experience becomes valuable in providing an extra label prescription.
There are two big classes of bacteria; gram positive and gram negative. Clostridial infections, such as blackleg or anthrax are caused by gram-positive organisms.
We were always told at veterinary school “p” for positive and “p” for penicillin. This older antibiotic is still effective against certain conditions and most veterinarians still use it on occasion.
Diseases such as blackleg produce toxins and the animal succumbs quickly so prevention in the form of vaccination is the only effective way to prevent it.
Proper dosage is also important. Twice as much as necessary will not be more effective and will only cost more and cause a longer drug withdrawal time. The safe rule is, if you double the dosage, you double the slaughter withdrawal.
In specific disease entities, supplemental drugs such as painkillers, anti-inflammatory medications or appetite stimulants can be given in conjunction with antibiotics to quicken or improve the response.
The selection of the appropriate medication for the specific disease takes thought. A major time saver is recording what products you use by either the active ingredient or trade name, and list the diseases it works well against, as well as the dosage.
Have a first and second choice. This will help make sure the appropriate product is given, especially by new workers.
Post drug dosage charts by the chute and have the slaughter withdrawal periods listed as well so drug residues don’t become an issue.
As well, it’s a good idea to have epinephrine handy in case of a drug reaction with the appropriate syringes and needles in a treatment kit.
