Farm management advice: In this article, CAFRE’s Nigel Gould discusses mineral supplementation for cattle at grass, slurry spreading, farm safety, closing silage ground and grass tetany.
Mineral supplementation for cattle at grass
Consider mineral supplementation at grass as mineral deficiency is a widespread problem in soils across Northern Ireland.
Selenium and iodine deficiency are a particular concern for suckler cow fertility.
However, it is important to note that while a mineral deficiency can impact fertility, if overall nutritional needs are not met, fertility will still be compromised.
Ideally, get a pooled blood sample from a group of untreated animals analysed to identify a deficiency.
If a deficiency is identified, you can supplement minerals using a range of methods. The bolus is often the preferred option for cattle at grass due to the low labour requirement.
Grass tetany
Grass tetany (Hypomagnesaemia) can be a higher risk in early spring as rapidly growing quality grass, with a high passage rate through the rumen, can lead to magnesium deficiency.
Lactating cows and ewes are most at risk due to their higher demand. Periods of wet weather can exacerbate the problem.
High levels of potassium in grass can also increase the risk as it can interfere with magnesium absorption. The body cannot store magnesium. Therefore a daily intake is essential. High magnesium lick buckets are the standard choice for grass tetany prevention.
Grazing management
In early spring, opening covers of 2,000-3,000 kg DM per hectare are acceptable.
Later in the season, when grass growth is at its peak, follow the rule of threes: aim to graze at the three-leaf stage, graze for three days and graze again in three weeks.
This means seven paddocks will be required. When the grass plant is grazed, it will typically grow a new leaf each week. This varies depending on growth conditions, taking longer in the shoulders of the season.
After the third leaf grows, the first will die. For this reason, grazing at the appropriate time means minimal dead material in the sward, resulting in higher sward quality. It will also serve to increase the total utilisable annual dry matter yield.
Closing silage ground
Aim to have silage ground that you are grazing closed by mid-April at the latest.
Late closing will push the harvest date further into June, at a time when grass will naturally tend to go to seed, rapidly decreasing D-value and overall quality.
Farm safety
The increased workload on farms at this time of year increases the risk of farm accidents occurring.
Be aware of the specific risks on your farm and take action to remove or reduce the risks, where appropriate.
‘Stop and Think SAFE’ is a farm safety campaign developed by the Farm Safety Partnership to address the high rate of farm-related injuries and fatalities.
The word ‘SAFE’ focuses on raising awareness of the four main causes of accidents: Slurry, Animals, Falls (from height) and Equipment.
Slurry spreading and cows after calving are particularly high risk on beef and dairy farms at this time of year. Assess all slurry equipment and PTO shafts, in particular, to ensure they are fitted with secure, sound guards and replace if required.
Furthermore, do not leave agitation points to slurry tanks open while unattended.
Be aware of the risk of hydrogen sulphide gas released from slurry during agitation. Do not agitate on a calm day; wait until there is a breeze that will dissipate the gas released.
Remove all animals from the shed before agitating. The first half-hour after the start of agitating is the period when the majority of gas is released.
Therefore, avoid being in the shed during this period. Ideally, have another person present or let someone know what you are doing beforehand.
Cows around calving time can be unpredictable and potentially dangerous. Do not presume a generally quiet cow is not capable of an attack, especially where she has a newborn calf at foot.
Do not turn your back on a freshly calved cow and have an escape route planned.
