Minerals are important for cattle throughout the year, but certain times of year require a little more management around mineral supplementing than others, and one of these times is pre mating.
Minerals such as Selenium, copper, cobalt, iodine, and magnesium all play a major role in the health and reproductive ability of the cow. After a winter, calving, and the start of lactation often these minerals are depleted by the premating period, which will impair her ability to cycle and get in calf.
It is for this reason we will often recommend daily trace element supplementation throughout lactation and an additional trace element boost of Multiminâ injected four weeks prior to the start of mating.
Selenium
Helps the immune system function, it reduces the incidence of metritis, retained membranes and ovarian cysts post calving. There is also evidence that selenium reduces the amount of early embryonic death in the first month of pregnancy.
Copper
Is also a big player in immune system function and helps bone development and connective tissue development in the calf.
Cobalt/B12
Is a major component of the digestive health of a cow. It stimulates appetite and helps with metabolism, which leads to better body weight and better reproductive outcomes.
Iodine
It is used in metabolism, growth, lactation and reproduction. A deficiency in iodine can cause many problems but pre-mating it can affect reproduction by causing non-cycler cows, low conception rates, and foetal abortion.
Magnesium
Magnesium is important for milk production and helps with muscle function and appetite. Cows need a daily intake of magnesium to meet these functions. If they become deficient they may have subclinical effects like a loss in appetite and a reduction in milk production.
Calcium
It is also important to mention calcium here, because during mating when cows are producing a lot of milk they can often become calcium deficient. This causes milk fever, a condition where cows become recumbent and die. If your farm has a history of milk fever it is a good idea to check calcium on the premating mineral check.
Thankfully most of these minerals can be tested via a simple blood sample sent to the lab. Copper can be a little misleading at times as the majority of it is stored in the liver and even when liver stores are becoming depleted the cow will try to maintain good blood copper levels. Blood tests for copper are still useful as bloods that are low in copper will tell us that copper stores in the liver are very low but what it won’t tell us where her liver stores are at. To do this you will need to have a few liver biopsies done by your vet or have livers tested for copper from cull animals sent to the works.
Selenium, Cobalt Magnesium and Calcium are all testable by blood sample. Unfortunately, the blood test for iodine only gives us a short-term picture of the cows’ daily intake of Iodine and this can vary between cows and their intake. Consequently blood tests are not routinely done for iodine.
It is important to find out the mineral status of your animals as some minerals can be toxic in high doses such as copper and Selenium. Overdosing can cause death in some cases, so more is not necessarily better when it comes to supplementing your cattle.
The premating period is a great time to check the mineral status of your herd, to get them supplemented with what they need and ready to get back in calf as soon as possible.
Pop in to your local clinic or give us a call to ask your veterinarian about blood tests and supplementing your cows for minerals.
Tararua Vets offers a comprehensive on-farm and in-clinic veterinary service. Our branches in Pahiatua and Dannevirke complement this service with carefully chosen animal health products and merchandise with up-to-date advice on their use.
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