There are several metabolic diseases that can affect cows around calving time, with many of these the result of not having cows at the optimum body condition score (BCS) at calving and also through incorrect mineral feeding levels during the dry period.
Some of these metabolic diseases include milk fever, retained placenta, and displaced stomachs – which can cause added stress and increased work in what is already a busy time period.
These diseases, and others, can also have a knock-on effect on a cow’s milk production potential as well her fertility performance.
- Milk fever: €130 per case;
- Left displaced abomasum: €515 per case;
- Grass tetany (clinical): €632 per case;
- Ketosis: €190 per case;
- Retained placenta: €392 per case;
- Cow death: €2,282 per death.
BCS
By now, February or early-March calving cows should be at a BCS of 3. If not, increase the meal being fed to these cows and ensure they are on ad-lib good-quality silage.
A study undertaken by Teagasc – on herds that noted persistent health problems during the spring period -found that very few of the problem herds were managing BCS in their dry cows correctly.
Over-conditioned cows in particular, have an increased risk of problems. Therefore, if cows are beginning to get too fat (BCS of 3.5 or greater) separate them out and put them on a restricted mix of silage plus straw.
Minerals
Teagasc recommends that minerals are fed four-to-six weeks prior to calving. There are many different methods available when administering minerals to cows includeing: boluses; mineral blocks/buckets; bagged/dusting; minerals through the water; feeding pre-calver concentrates.
There are advantages/disadvantages to all of these methods. The most common method used by Irish farmers would be dusting. This is where farmers buy bags of minerals and feed twice-a-day on top of silage.
This is one of the cheapest methods; however, feed space is vital to ensure all animals have access to minerals.
Always read the label and make sure animals are getting the required amount. This method usually requires approximately 120g/head/day.
When picking the right minerals, it is important to ensure the correct minerals and vitamins are in the pre-calver at the correct rate.
Calcium, phosphorous, sodium and magnesium would be considered major elements whereas, copper, selenium, iodine, cobalt, manganese and zinc would be microelements and vitamins A, D3 and E are also essential in pre-calver minerals.
Too much phosphorous can prevent calcium uptake. Copper is essential for enzymes to work, while selenium and vitamin E are also very important for immune function and help to prevent white muscle disease.