What percentage of antibiotics are being used on cattle?

Answer 1

A common misconception is that 80% of antibiotics used in cattle (or livestock in general) are used in humans. The fact of the matter is that to generate such a percentage is not that simple as simply getting some simple percent to wave around in everyone's faces.

There are many more livestock in North America (more emphasis placed on the US of A) than humans, and most of these livestock are larger and need a bigger dose of medicine--including antibiotic--than the average human needs. Also, many antibiotics used in human medicine are different than what are used in animals.

See, 13 percent of antibiotics, in the form of ionophores (the most common form, being monensin, is not used in humans) make up the antibiotic total. The rest of the total of what the FDA had provided--as in a little over 13 million antibiotics--are used for sick animals, not on healthy animals just so the farmer can "make a quick buck."

Bottom line is that it is quite impossible to glean an exact percentage of antibiotics used in livestock like cattle, no matter how you try to look at it or work around it.

Answer 2

In the context of this question, it depends on who the person this question is directed to, and if you are asking about general antibiotic usage in cattle or what antibiotics will be needed to be used in cattle regarding health and/or productivity.

As such, the factor to which this question holds a lot of ambiguity to is whether this is addressed to the general public (the 98% of the population who are not farmers nor raisers of cattle), or to the cattle producers themselves, regardless where on the production "line" they stand and what type of cattle they raise, makes this question nearly impossible to answer without going into great detail and creating more reading material for you, the viewer, to take in.

Thus, it is best to address this question in assumption that, a) it is directed to a cattle producer, and b) what antibiotics are needed to be used regarding health and/or productivity.

What a cattle producer should know regarding cattle health and use of antibiotics:

Antibiotics or antimicrobials are drugs which target specific species of bacteria in the attempt to force a die-off through chemical and physiological microbiological means which are often beyond the scope of understanding of the average cattle producer--but certainly not those whose jobs as nutritionists and/or veterinarians help keep their operation going. Such medicines are and should be used for what are called bacterial infections to provide the most effectiveness. If they are used to target infections caused by viruses or fungi, they are ineffective and a waste of money to even consider purchasing.

Most antibiotics by veterinary pharmaceutical companies (which also create medicines and vaccines for humans, just under a different compartment) are created for use at therapeutic levels--levels which are to be used on sick or dying animals. These antibiotics are not to be used on healthy animals. There are antibiotics created for the purpose of being used as feed additives--to be supplemented orally by mixing it in with the feed a producer is giving to their cattle--and these cannot be confused nor mixed with the antibiotics which are created to be injected via needle and syringe into an animal.

What antibiotic to use depends on the disease your cattle are experiencing, how effective you are wanting a certain antibiotic to be and how much you are willing to spend on that antibiotic. To give you an idea, for shipping fever and pneumonia alone, there are at least 10 antibiotics to choose from.

Antibiotics always show dosage rates on the box and/or bottle. It is highly recommended that you, being the cattle producer, follow these dosage recommendations to a T, unless otherwise specified or directed by your veterinarian. Dosage rates give you the amount to give per unit of body weight (either in per 100 lb body weight or per 10 or 50 kg of body weight--whatever is mentioned on the bottle, in the pamphlet that comes with the bottle, or the box the bottle came in), in either cc's (cubic centimeters) or mL (millilitres). Always know that 1 cc = 1 mL.

Further instructions will tell you if an antibiotic you purchased needs to be injected under the skin (subcutaneous or subQ), or in the muscle (intramuscular or IM). Very rarely is an antibiotic needed to be injected in the vein (intravenous or IV), so rarely that it is impossible to find such an antibiotic that can be used as such. Other instructions will tell you which animals you can use this antibiotic on (and which animals you must avoid giving it to), how often to inject this antibiotic, when it is safe to terminate use, and the withdrawal dates you should follow should you choose to slaughter or send to slaughter this animal which you are treating. It also comes with a warning and instructions for proper management and how to deal with this antibiotic if you accidently inject yourself with it. (Yes, it does happen!)

As mentioned above, there are antibiotics that are used on unhealthy, sick or dying animals, which are therapeutic antibiotics. However, there also exists another two classes of antibiotics, which are sub-therapeutic antibiotics and ionophores. Both are feed-additives. A producer who is operating a feedlot or is finishing or feeding cattle a high-concentrate diet must know about these antibiotics and their use.

Sub-therapeutic antibiotics are antimicrobials which are used to prevent common diseases from afflicting feedlot cattle, such as shipping fever, microbial diarrhea, bacterial pneumonia, liver abcesses and others. These are used in healthy cattle. These antibiotics come in the form of a feed additive which are added to and mixed with the feed that is to be fed to cattle. Just like with therapeutic antibiotics, these antibiotics also come with dosage rates, class, weights and type of animals it can be used on (as well as those which to avoid) and withdrawal times which must always be followed. Dosage rates often come in the form of mg/kg (miligram per kilogram).

Ionophores are also antibiotics or antimicrobials which are used in healthy cattle. They are used as a means to prevent cattle from getting acidosis or bloat, but, however ironic it may seem, not liver abscesses. (While ionophores do not prevent liver abscesses, they do reduce instances.) It's microbial action is in the rumen, where it targets most gram-positive bacteria, protozoa and fungi in the effort to increase rumen pH, reduce methane production and increase protein availability to the ruminant animal. As a result, ionophores increase feed efficiency (or improve feed conversion - feed:gain ratio), increase average daily gain (ADG), and improve consistencies of feed intake.

Ionophores come with a dosage rate that must be followed to prevent loss of 50 percent or more of your herd from overdosage of ionophore and to prevent increased rates of acidosis and bloat if you underdose this additive. It also comes with a warning to avoid feeding it to certain animals which may be very sensitive to its effects (such as horses, which, if fed >2 to 3 mg/kg of ionophore, could result in death [in comparison to horses, the lethal dose for cattle {in killing 50% of animals} is 20 to 30 mg/kg]), and, as with every antimicrobial substance, a withdrawal period.

Basically, with any antimicrobial product you purchase for whatever reason prompts you to purchase it, it is very important to read the instructions carefully and in its entirety in order to know what to use and how to use a certain antibiotic for your cattle.