Current rules outlined by the Association of American Feed Control Officials (AAFCO) state that copper minimum and maximum levels are required on labels for sheep or goat products where the amount of copper in the formula is at, or exceeds, 20 ppm. So what does this mean? In simplistic terms it means that the background levels of copper are at 20 mg per 2.2 lbs of product (9 mg copper per pound of product) or greater. When a formula contains less than 20 ppm copper, no copper guarantee is required and thus those labels will look different than those of formulas containing 20 ppm copper or greater.
How Does Copper Get Into The Formula?
Copper is a naturally occurring element in plants and soils. As such, ordinary feedstuffs such as grains, molasses and forages will naturally contain copper as well as other minerals. Additionally, mineral ingredients, such as dicalcium phosphate or calcium carbonate, will also include residual or “background” levels of copper as well as other minerals resulting from imperfections in processing.
So as you can see, it is not only possible, but probable, for a feed or supplement to contain a certain amount of copper even though elemental copper is not added to the formula and is not listed in the ingredients statement. Modern computer software and regular ingredient testing makes it easier to detect and track these background levels of copper than ever before.
Sheep Actually NEED Copper
While sheep owners have been told for decades that sheep can’t receive copper due to toxicity, this is only partially true. Yes, it is true that sheep (especially those with wool vs. hair) are sensitive to copper toxicity because their bodies have difficulty excreting excess copper. However, copper is vital for proper nutrition and sheep do have a daily requirement for copper. Of course, these levels will vary depending upon the concentrations of sulfur and molybdenum in the diet. Breed differences also affect copper requirements as some breeds absorb and retain copper at different rates. As a whole, sheep with wool tend to be more susceptible to copper toxicity than sheep with hair.
Copper is needed by a variety of key systems in the body for reproduction, immunity and growth. Copper plays key roles in wool production, stress resistance, development of antibodies and red blood cells, pigmentation of skin, wool and hair, maintenance of hoof tissue and many other functions. Copper deficient sheep have steely wool that is lacking in crimp and tensile strength. Additionally wool may lose its pigmentation. Lambs born to copper deficient ewes may experience congenital nervous disease. These lambs express symptoms of swayback or may have difficulty standing or walking. Affected lambs may die due to inability to nurse. Other symptoms include anemia due to insufficient red blood cell production and fragile bones susceptible to spontaneous fractures.
Should You Worry About Background Copper?
Now that I’ve revealed to you all of the hidden sources of copper that you never knew about, you’re probably wondering about the safety of your favorite feeds and supplements. Remember that regulations state that a copper maximum must be guaranteed for sheep products. Manufacturers are required by law to stay within tolerances and not exceed the stated level. As I stated earlier, modern testing techniques and computer software allow manufacturers to accurately monitor copper levels. SWEETLIX products designed specifically for the nutritional needs of sheep have been properly balanced to stay within safe limits of copper for all classes of sheep.
Changes in copper guarantees were required in order to comply with current regulations. These copper levels reflect background levels of copper coming from ingredients other than elemental copper. SWEETLIX animal nutritionists have taken background levels of copper into account and have determined that safe levels are being delivered. Supplement products labeled for use in sheep are safe for use in all classes of sheep unless otherwise stated.