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  1. Product Safety Information

The Center for Veterinary Medicine Safe Food Facts: Storing, Handling and Using Animal Milk Replacer Products


Newly born mammals depend on milk as their sole source food, but when milk is not available, milk replacers can provide the nutrients and fluid necessary for the neonate to thrive. The composition of milk, such as the amount of solids and the types and amounts of proteins and fats, differs between species. Using milk replacers successfully requires following the directions on the label and observing proper hygiene.  A milk replacer that is not mixed correctly, fed to the animal inappropriately, given to the incorrect species, or is defective in some way may cause the animal to become seriously ill or die.

Newborns don’t have a reserve of essential nutrients and fluids to compensate if milk is not available and they can’t digest or utilize excessive quantities of these substances either. It is, therefore, essential to understand how to properly provide milk replacers to newborns. Milk replacers are formulated for specific species of animals according to their nutritional requirements and physiology. Consumers should use extreme caution when using these products in species other than the intended species specified in the labeling.

The structure, nutritional value, and solubility of milk proteins and fats in milk replacers, may be altered by improper processing, handling, or storage.  Fats may become rancid if exposed to excessive temperature and oxygen at any time prior to use.  Casein, the major protein in cow’s milk, is by itself not very soluble in water and mostly exists in milk in a complex structure known as the casein micelle. If the structure or composition of casein micelles is altered, the casein can clump together. Exposure to low pH (acidity), heat, proteolytic enzymes, such as rennin, and age can all cause casein to clump together. Milk replacer products, therefore, should not be mixed with any ingredients other than those included in the label instructions for reconstitution. Different brands of milk replacers and different types of milk replacers of the same brand should not be mixed.

Before feeding a milk replacer, check the expiration date and make sure it does not smell rancid, or have an unexpected or uncharacteristic odor or texture.  If the product does not look, smell, or mix as expected, it is probably best to not use the product and to contact the manufacturer, even if it is before the expiration, use by, or best by date.  The manufacturer and retailer may allow you to return the product or advise you to discard it. If a product is at all suspicious it should not be used and should be discarded.

The expiration, best by, or use-by dates apply only to the manufacturer-sealed packaging. Once a container is opened these dates to not apply to the unused portion of the product. This includes powdered products.  Reconstituted product should be prepared for one time use and any unused reconstituted products should be discarded immediately after use. Complete storage instructions should be included in the product’s labeling. The consumer should contact the manufacturer for guidance when storing products in a manner other than what is specified on the label.

If an animal appears sick or fails to thrive as expected on a milk replacer product, stop using the product and call a veterinarian immediately.

If you have concerns that any animal food product may be the cause of an animal illness or death, or is defective in some way, you should report it to the manufacturer and the FDA.  You can report pet or livestock food complaints electronically to the FDA through the Safety Reporting Portal, or you can call your state’s FDA Consumer Complaint Coordinators.

Additional Resources

Medicated Milk Replacers

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