Pharmaceutical products (vaccines, antimicrobials, other injectable or oral drugs, fly control products, dewormers, intramammary tubes, teat dips, etc.) represent a large investment that helps decrease incidence of disease, mitigate the severity of disease, and improve animal health and productivity.
When handled and used correctly, they are predictably safe and efficacious and are usually cost effective. However, improper storage can not only reduce their effectiveness but also increase the risk of adverse reactions or inappropriate use of these medications. Proper and orderly storage of pharmaceuticals also reduces inventory shrink, which happens when drugs go out of date, containers are broken or products disappear.
Inventory
Managing an appropriate inventory of drugs ensures that certain products are available when needed and unnecessary stocking of underutilized products does not tie up excess cash resources. Few farms have an active inventory management system in place and just order things when they are close to running out (or after they run out). In a perfect world, the drug inventory would be tracked along with disease-incidence information, which may allow for timely ordering and appropriate inventory stocking.
A great time to review the drug inventory is when reviewing animal health protocols or standard operating procedures (SOPs) on an annual or semi-annual basis. Every drug on the shelf should be tied to an SOP, and every product on an SOP should be in inventory in an amount consistent with disease incidence and ability to restock shelves when necessary.
Most dairies are careful about orderliness, expiration dates and proper drug labeling for their lactating-cow drugs because of periodic regulatory inspections, but we have witnessed that this may not be the case on other areas of the farm, where inspectors may not routinely look. Drugs stored in calf barns, heifer working facilities and in vehicles often get lost, broken or forgotten. This leads to excessive product utilization or wastage, which may be a significant opportunity cost on some dairies.
Access to drug storage rooms should be limited to trained employees. Many of the products utilized on farms pose some risks to animals or individuals on the dairy and should always be used with caution. Additionally, all treatments should be administered and recorded by trained herd-health personnel in an effort to provide appropriate and timely treatment while reducing the risk of milk or meat violative residues on the farm.
Cleanliness and orderliness
Medications should be stored according to their utilization category, with medications stored for non-lactating cows kept isolated to prevent inadvertent use that may create violative milk and meat residues. Areas for storage should be well-lit, so that it is easy to read product labels to avoid inappropriate use of medications. Additionally, many product bottles look very similar and it may be necessary to label shelf space for individual products.
Drug carts and totes are a convenient way to carry drugs from the storage area to animals, but they can quickly become disorganized. At the end of a treatment day, all drug storage carts and totes should be cleaned and restocked for the following day. Used needles should be discarded in approved sharps containers to avoid needlesticks. All used single-use syringes should be discarded, and reusable syringes should be cleaned and dried. If reusable syringes are utilized for vaccine delivery, the syringes should be cleaned with hot water and thoroughly rinsed and should not be cleaned with disinfectants, as this may inactivate vaccines.
Protective sleeves should be used to reduce the risk of breaking glass bottles. Many large-volume bottles provide product at a much cheaper price per dose; however, breaking a bottle will often eliminate any potential savings. Bottle sleeves are often available from product distributors or manufacturers and should be utilized whenever possible.
Medications should be stored inside a building or cabinet with a secure latch to prevent buildup of dust, debris or manure on the bottles. If the cap of a bottle is visibly dirty, it can be cleaned with 70% alcohol wipes prior to withdrawing medication. Cattle are much more tolerant than other animals to dirty injections; however, they can develop abscesses or other adverse reactions to contaminated products and administration equipment. Additionally, the reuse of syringes and needles increases the risk of spreading contagious diseases, such as bovine leukosis and anaplasmosis.
Most medication bottles are rated for a certain number of punctures through the rubber cap, and exceeding those recommendations may lead to product wastage, evaporation or bottle contamination. For large, multi-dose bottles, it may be necessary to use a tube-fed automatic syringe with a draw-off spike, which should not be removed until the bottle is emptied. Leaving needles in bottles allows an easy route for contamination of the product. Multiuse bottles should only be punctured with new, clean needles to avoid additional contamination.
Heat stress
Even if they do not require refrigeration, many products can be damaged by exposing them to high temperatures. Labels on these products often recommend storage at room temperature (59°-86°F or 15°-30°C). Unless they are stored in air-conditioned rooms, this is very hard to maintain in the summertime. Because this damage is cumulative, drugs that must be used in outdoor environments should be out of storage for the least amount of time possible. Medications stored in vehicles are at an increased risk of heat damage, as vehicular temperatures often soar over ambient air temperature. For some products, evaporation over time may increase concentration of the active ingredients and simultaneously increase the risk of adverse reactions occurring.
Refrigeration
The monetary investment stored in the farm refrigerator often far outweighs the quality or reliability of the refrigerator. We have seen too many hand-me-down household refrigerators with thousands of dollars of vaccines and pharmaceuticals stored inside. These household refrigerators, especially if doors do not seal well and they are old and have dirty cooling systems, may not be maintaining the correct temperature or quickly recovering that temperature after they are opened.
If these refrigerators are utilized for storing vaccines, and there is an issue with stability of the product, it could lead to significant production losses in the event of disease challenge. The risk of having a refrigeration failure is not just in the cost to replace the products inside, but also in the increase in disease costs if there are unidentified issues associated with storage. Vaccines that have lost efficacy can increase the risk of disease occurring, which may not be seen for many months.
We recommend use of wireless high-low thermometers to monitor refrigerators and their valuable contents. These monitoring devices can be fairly inexpensive, and some pharmaceutical companies offer them at little or no cost to their customers. One simple step to help ensure safety during medication storage is to maintain a daily temperature log, recording the high and low temperatures the refrigerator experiences. Once you know the current temperature of the refrigerator, you can then dial in the settings to match the recommendation on the product label. Most vaccines recommend a temperature of 35°-45°F (2°-7°C).
Freezing these products or storing them at higher temperatures may render them completely ineffective or may actually increase the risk of adverse reactions. In some vaccines that contain gram-negative bacteria, freezing or overheating can release more endotoxin (LPS), which can cause serious side effects in animals. Care should also be taken to avoid storage on the top shelf of a refrigerator (where cold air outflow could freeze products) or in the door of the refrigerator, as it often experiences significant temperature fluctuations.
Recommended action items
- Work with your veterinarian to develop SOPs for disease treatment and prevention, if not already in place.
- Begin by organizing and inventorying your current pharmaceutical drugs and vaccines.
- Discard expired products and any products that appear to have changed color or have debris present in the bottle, indicating potential contamination.
- Compare drug inventory with SOPs and update each as needed.
- Develop a plan for how much inventory to have on-hand and what locations on the farm will hold inventory (calf barn, etc.).
- Evaluate the quality of refrigeration equipment (temperature recording) and the risk and cost of failure of that equipment.
- Assign the responsibility of pharmaceutical inventory and management to one person and create a schedule of actions to ensure the investment is well managed.
- Evaluate treatment records and determine if there is potential waste of product or loss of inventory.
—This origianlly appeared in the Georgia DairyFax newsletter, July August September 2020.
