MAXIMISING weight for age in calves should remain a vital priority in the months leading up to housing as the greater the housing weight the reduced pressure on meeting growth targets during the winter period.
A number of areas dictate this, namely:
- Grassland management
- Parasite control
Grassland management: Whether or not meals should be fed from August onwards is dependant on the standard of grassland management on the farm. If calves are getting a constant supply of leafy grass 8-10cm in height (1,000-1,400 kg DM/Ha) and weather conditions are good, then meals can be cut out for these months.
Concentrates: If however they are being forced to graze poorer-quality swards and/or the weather is unfavourable (especially wet weather), then there is a benefit in feeding a small amount of concentrates daily. Feeding over 1.0kg per day to calves is not only costly but also reduces their grass intake, which then makes grassland management even more challenging as they are longer grazing down paddocks.
Parasite control: Stomach worms and hoose need to be kept to a minimum in young calves in their first year at grass. Calves have no immunity built up to them and they can dramatically reduce their daily performance if treatment for them is delayed. However, recent studies have shown that resistance is building in stomach worms to the different wormers that are on the market.
Essentially, this means that they are not as effective at killing these parasites as they used to be and, if we are not careful, they may be of no use to us in years to come if their efficacy continues to decline. One of the key steps to slowing down the problem of resistance to wormers is to only use them when they are needed.
Pooled fresh dung samples taken from a batch of calves can be sent to a laboratory and, for a very small fee, they can quickly tell you whether or not the calves need to be dosed for stomach worms. This is now considered best practice rather t han treating calves based on the number of weeks they are at grass.
Treating for hoose is different. Once calves start showing the signs of hoose, i.e. coughing after running, they should be treated immediately with an appropriate wormer.