Before the 1980s, copper deficiencies were a real problem for just about anybody raising cattle from Western Canada to Cape Canaveral.
Extensive copper research in beef cattle undertaken by Canadian and a host of international universities and governments, followed up by practical copper supplementation programs used by many producers has made severe copper deficiencies on cow-calf operations, a thing of the past.
Despite some of our best efforts, however, subtle or marginal copper deficiencies in cattle still are still with us. Without adequate testing and investment into a well-balanced mineral program, they can negatively affect the breeding season, future calf crops and final farm revenue.
Don’t go by colour
Oddly, we’ve all been taught the classic copper deficiency lesson; “copper deficiencies causes black cattle to turn gray and red cattle to turn yellow.” This tagline might work in the most severe copper deficiency cases, but is misleading when trying to determine whether your herd is suffering from marginal copper status, where deficiency symptoms are invisible, yet underlies frustrating poor performance.
- From the Canadian Cattlemen: A midterm checkup for your feeding program
In hard-to-pinpoint copper cases, it is important to recognize that micro-amounts of copper are required by all cattle; involved as activators of vital enzyme systems (specialized proteins) that drive cellular reactions in many areas of cattle maintenance and performance. Here are a few metabolic examples of how copper functions through these enzyme system.
- Vital functions — Copper plays many life-giving roles in the body. Case-in-point, it plays an irreplaceable role in respiration because it is essential to hemoglobin synthesis (compound that carries oxygen in blood) and red cell maturation. Copper also affects iron absorption in cattle (active metal in hemoglobin). Anemia is therefore a common condition in marginally copper-deficient animals.
- Immunity — It is theorized that within cattle immune systems, copper along with zinc, manganese and selenium play a pivotal role in antioxidant reactions, which destroy dangerous compounds known as “free radicals” produced during a normal immune response against disease. It has been proven by indirect evidence such as elevated copper levels present in white blood cells responding to infections and inflammation.
- Reproduction — Although well-defined biological pathways are unclear, copper plays a role in hormone production, normal estrus cycles, egg release, fertilization of the egg and early embryonic survival. Marginal copper deficiencies may lead to delays in cattle puberty, silent heats, failure to conceive, greater incidence of early embryonic deaths or overall lower pregnancy rates.
- Hooves — Copper has an important role in connective tissue synthesis and keratinization (hardening) of hoof horn in cattle. Cattle with a marginal copper deficiency are predisposed to heel cracks, foot rot, sole abscesses and other types of lameness.
This informal checklist might explain an odd year or series of years when a herd should have performed better (re: calving and breeding seasons), despite the cows being in relatively good shape for much of the year. One might ask: Is this just the experience of an “off” season or caused by a copper deficiency that was previously unknown?
It is easy to verify the copper status of most cow herds. It can save a lot of time, effort and money just by analyzing forage and feedstuff (including water samples) to determine their copper and other complete mineral profiles. Similarly with the assistance of a veterinarian, tissue (liver biopsies) and blood samples from cattle might be taken and analyzed for copper and other trace mineral status (zinc, and selenium). The results of these tests might indicate appropriate corrective action is needed to reverse an established copper deficiency.
Proper mineral mix
Correcting a verified marginal copper deficiency in many cow herds can be a straightforward matter of feeding a well-balanced commercial mineral containing supplemental copper. The NRC copper requirement for young and mature cattle is no more than 15 mg/kg of diet (dm, basis), which takes care of the beef animals’ basic copper requirement and also takes into account the antagonistic effects upon dietary copper by moderate molybdenum or sulphur levels in forages, other feedstuffs or water. Therefore, a purchased mineral containing 3,000 mg/kg of inorganic copper (added as copper sulphate) and fed at 50-100 grams per head per day should solve most copper deficient problems.
The following nutritional and management suggestions are also helpful in assuring your beef cows receive enough dietary copper:
- Target cow herd mineral consumption — The best well-formulated mineral containing adequate copper levels cannot do its job unless cattle eat it. Target the above mentioned 50-100 grams per head per day.
- Know the dietary copper sources in your mineral — The copper concentration on the mineral’s feed label is useful, but of limited information. Copper comes in many forms such as copper oxide, copper sulphate, and chelated copper forms, which have relative biological availabilities of five per cent, 100 per cent, and 125 to 150 per cent in cattle.
- Consider feeding “Breeder mineral” all year long — some producers feed a more fortified cattle mineral (with more biologically available organic copper) all year long, saying that the cost-difference between a basic and such a fortified mineral calculates up to $10 per cow per year, yet it is worth the assurance of good copper and other essential mineral status at all times.
- Fill your mineral feeders on a regular basis — Mineral feeders should be filled every two to three days and hardened old mineral should be removed. Check the condition of your mineral feeders and replace those that are broken, and beyond repair.