Specialists at Texas A& M University provide the following recommendations for treating range cattle.

When chlortetracycline (CTC) is mixed in a free-choice formula, it is important that no other source of the nutrient be available to the cattle. For example, when a salt mix is used as a vehicle for the CTC, no other source of salt should be available. If a calcium/phosphorous/mineral mix is used as a vehicle for the CTC, then no other source of these minerals should be available. Under these circumstances, the medicated supplement must provide the daily required supplemental amounts of the nutrients. When formulations have been designed to provide only salt at the required nutritional level for range cattle, all other required nutrients must be supplied from the pasture or other supplements.

Feeding Free-Choice Supplements


  • The range mix should provide the only source of supplemental salt available.
  • Place the medicated supplement in several areas where cattle will congregate in the pasture (for shade, water, etc.).
  • Begin feeding the medicated supplements by putting out only a 2- or 3-day supply in the pasture. This will allow you to accurately measure consumption and make proper adjustments to achieve the desired medication intake. Adjustments to either encourage or discourage the consumption of the medicated supplement can be made by changing the formulation of the supplement or by changing management practices.
  • When the correct consumption rate has been achieved, then place a 1-week supply of the medicated supplement in the feeders. To ensure the potency of the medication, lace no more than 1 week’s supply of the supplement in the feeders.
  • When using chlortetracycline (CTC) as an aid in the control of anaplasmosis, feeding supplements containing CTC should begin before and continue through the vector season.



Increasing Consumption of Medicated Supplements


  • Increase the level of palatable ingredients (CSM, SBM, or dried molasses) as the level of the salt is decreased.
  • Feed the medicated supplement in feeders which also contain the calcium/phosphorous supplement. Place the feeding stations throughout the pastures at the locations where the cattle normally gather (shade, water, etc.)



Reducing Consumption of Medicated Supplements


  • Increase the salt level at the expense of more palatable ingredients.
  • Reduce the number of feeding locations.