Health of herd is of primary importance
Vaccination against this disease has become routine; it can cause serious human health problems and every herd should be vaccinated.
Mastitis, lameness; parasites and metabolic diseases are constant threats, but can be kept under control in well-managed herds. All aspects of the Teagasc mastitis control programme should be careful-ly followed.
For example the milking machine should be in perfect working order, chronically infected cows should be culled, cows should be calved in well disinfected areas and good milking practices such as teat dipping/ spraying should be carefully carried out.
Cubicles should be kept thoroughly clean and dusted with lime, especially around calving time when cows are very susceptible to mastitis infection. Mastitis infections around calving time can affect udder health for the remainder of the season.
Lameness is still a problem in many herds. Cows that are not lying in cubicles or showing any signs of lameness should be removed to a straw bedded house or soft bedded area before serious lameness infection sets in. Cows should be prevented from walking on rough areas as this a major cause of lameness. Preventative foot bathing and treat-ment should be carried out regularly.
Parasite infections are relatively easy to control, by fol -lowing a preventative programme, but are often neglected. Most young stock get adequate treatment for internal parasites at housing.
Dosing cows for worms is a practice that is increasing. There is evidence that it improves milk yields and fertility, as well as condition. Check products for safety and withdrawal periods. All Moorepark herds are dosed for worms every year.
Animals on most farms should be properly treated for fluke, or samples should be tested, at least.
Perhaps the parasite treat-ment that is most neglected is for lice. The damage that lice can do is underestimated. They can kill, but of course the usual effects are poor performance and susceptibility to other diseases.
Lice products have different coverage periods, but animals generally need a few treatments during the winter. Check products for safety and withdrawal periods.
Metabolic diseases are causing frequent problems at both clinical and sub clinical level.
Losses from Diseases
It is well known that the top 20% of dairy farmers have double the profitability of similar farmers in the lowest 20%.
Much of the profit gap is due to disease, especially subclinical diseases that farmers might not easily notice.
Many farmers don’t fully realise the effect that disease is having on their herds, and are not taking proper preventative action.
The first step is to involve your vet in a complete herd health programme.
Estimate of Losses
UCD and Vet Ireland have estimated the losses associated with the following diseases (see table, right). These losses include vets’ time, drugs, far mers’ time, discarded milk, reduced milk, reduced fertility, high culling, extra cost of AI, and fatalities.
Most farmers would find these costs surprising, but they were well researched, and are accurate when the overall situation on farms is taken into account. These figures should drive home the message that disease prevention is essential for success.
Clinical and subclinical (SCC) mastitis are obvious; but subclinical cases of other diseases often go undetected. Every farmer should assess their own situation with their vet.
Metabolic (Feed Related) Diseases
There are some very common health problems in dairy herds at this time of year, which can largely be controlled by feeding and management.
Having cows in proper condition at calving, followed by proper feeding after calving, will go a long way towards eliminating these problems.
If they occur regularly, consult your vet and Teagasc advisor. The first step is to have in-calf heifers and cows fed properly during the dry period, including minerals, and calving down at condition score 3.25-3.5.
Milk Fever
The feeding of 4 to 5 ounces of a good pre-calver mineral (Teagasc standard) per day for about 6 weeks before calving helps to prevent milk fever as well as other problems. Three to four ounces of limestone flour fed at calving and again 12 hours later is also helpful in problem cases. Avoid having cows too fat at calving. Some commercial products, including DC100, fed for about 10 days before calving seems to be very successful in problem herds.
Ketosis
Some level of ketosis is common in many dairy herds. It usually occurs in cows losing too much body condition after calving.
This may be due to cows being over-fat at calving, which reduces feed intake after calving, or poor quality silage, or very low meal feeding. The symptoms are dullness, going off feed, a sudden drop in milk production, and a characteristic smell from cow’s breath, milk and urine. Contact your vet at the first sign of the problem.
Like many other diseases, the most serious losses are incurred where there is a low level of the problem throughout the herd, and the poor performance or ill-health are not readily identifiable.
Acidosis
Acidosis is generally caused by digestive upsets. A sudden increase in concentrates after calving, or feeding high levels of concentrates containing too much starch or acid ingredients, is a frequent cause of the problem. Very low pH silage also increases the risk.
As well as a reduction in appetite and a drop in yield, there may be a general lack of thrive, panting and laminitis, causing lameness. The best preventative is to feed adequate fibre and a fibrous dairy ration. Also introduce concentrates gradually after calving, especially if concentrates are not fed before calving. The feeding of alkaline substances such as bread soda may be helpful, but feeding some fibrous food such as hay will usually prevent the problem.
Difficult Calvings
Difficult calvings and weak calves can cause major losses, ranging from deaths to infertility to poor performance.
As with the metabolic diseases referred to above, proper feeding during the dry period and disease control will help minimise the problem. High quality dry cow minerals and bull selection are essential aids in minimising and preventing calving problems and retained afterbirths.
Infertility
Infertility is still one of the biggest problems on dairy farms, with an average calving interval of around 400 days. While it is not always related to nutrition, trials have proved that having cows in proper condition score at calving down, and in the runup to and during the breeding season, has a major affect on conception. Only bulls with a high fertility sub- index should be used to breed fertile cows.
Mineral /Trace Element Deficiency
Pre-calving minerals containing high levels of trace elements and high in magnesium should be fed for about six weeks before calving. These help prevent weak calves, calving problems, retained afterbirths, infertility, milk fever etc.
Always follow recommended feeding rates, which are generally about 4-5 ozs per cow per day.
