LIVESTOCK MONITOR

Press, 20 September 1985, Page 12

LIVESTOCK MONITOR

The lambing percentage in Malvern County does not appear to reflect the relatively dry conditions in April. Most farmers are experiencing a good lambing, with a high proportion of twins in many flocks, according to the Darfield office of the M.A.F.

The lambs, including twins, are tending to be large, and farmers just beginning lambing may need to watch for dystocia. There is a very fine line in the feeding level between dystocia and sleepy sickness. The main aim should be to have the ewes on relatively tight rations, but good quality pasture. The moisture levels around Darfield are good, with soils at field capacity. Down country from Kirwee, the soil is a lot drier, and at Templeton, although surface moisture is adequate, moisture levels at depth are low. The feed situation is improving with the adequate moisture and warmth. Farmers that applied nitrogen are definitely reaping the benefits at present, with good, high quality pasture, said Caroline Carter, farm advisory officer. The monitor flock is about one third of the way through lambing, and the hoggets officially began on September 17. The ewes in the monitor flock, which are still to lamb, average 69kg, an increase of 7kg since mid-August. The hoggets average 47kg, close to the target lambing liveweight of 48 to 50kg.

They have gained 4.5 kg since mid-August. The ewes will receive a drench at tailing, to minimise parasite problems. This will be, on average, about three weeks after the beginning of lambing. Current research suggests that this is the optimum time to drench, to minimise early worm burdens in lambs. Looking ahead to the end of September, the monitor farm intends to sow rape in the paddocks which were affected by porina, for summer feed. The last of the silage is being fed to the hoggets and late lambing ewes. It will soon be time to start thinking of closing up paddocks for next winter’s supplementary feed. SHEEP: This spring so far as been quieter than usual at the M.A.F. Lincoln Animal Health Laboratory, according to a veterinarian, Dr Alan Pearson. This could be due to lower ewe numbers, mild weather and drought conditions in some areas. @ A common problem in ewes at this time of the year is gangrenous mastitis, commonly known as “black bay” — not to be confused with blackleg which is a type of blood poisoning. Gangrenous mastitis usually occurs in ewes that are good milkers and may be particularly common when lambs are weaned early. The affected side of the udder is initially hot, swollen and painful; first signs may be a hungry lamb or the ewe may appear lame on the affected side. A high dose of penicillin is the best treatment, but while this usually saves the ewe, the affected udder is often beyond repair and may even drop off in severe cases. Prevention is better than cure and if farmers have a high incidence of this problem in their ewe flocks a veterinarian should be consulted about preventative measures. © Vaccination of lamb against clostridial diseases at tailing is a must on many properties. However, as with so many preventative' techniques, blanket recommendations are inappropriate. Various combinations of clostridial disease vaccine are available and your veterinarian is best qualified to advise on the requirements for individual properties. With the possibility of low lamb prices this year a simple cost benefit calculation may assist you to make a decision on vaccine use. For example on properties which have experienced large outbreaks of tetanus or pulpy kidney in previous years, the potential value of lambs lost will far exceed the cost of vaccination. Goats are also susceptible to clostridial disease especially tetanus and pulpy kidney. With the current goat prices all kids should be vaccinated according to your veterinarian’s instructions. • Other common problems at this time of the year are associated with tailing procedures, Use of unhygenic tailing&nethods can cause

major problems with arthritis and spinal abscesses in lambs. In these diseases bacteria are absorbed from the stump of the tail into the blood stream and localise in the joints or spinal canal. Lambs with arthritis are obviously lame with hot swollen painful joints in one or more legs. Penicillin injections are the best treatment. Spinal abscess is less common; affected lambs have weak or paralysed hindquarters and usually do not respond well to treatment. Lameness caused by these diseases should be differentiated from white muscle disease. Preventation of arthritis and spinal abscesses relies on the use of clean, well maintained tailing equipment and tailing lambs in temporary yards in a clean paddock will reduce the risk of infection. Rubber rings are often the most hygenic method of tailing but using them increases the risk of tetanus. DAIRY CATTLE Calving is a stressful time for the cow and may result in a number of health problems. Amongst these three common disorders are retained foetal membranes, scouring and acute mastitis. © Cows that retain foetal membrances or “do not clean” are best left alone if they are showing no other signs of illness. Applying undue force to the retained membranes will damage the lining of the uterus and impair fertility. The membranes will usually detach themselves over a period of seven to 10 days. The only problem with this is the offensive, smell in the cowshed. A proportion of these cows will show signs of illness and in these cases veterinary attention should be sought. • Scouring in cows that have recently calved may be caused by ostertagiosis. Ostertagia is a worm that may remain dormant in the immature stage in the lining of the gut. The stress of calving results in a lowering of the cow’s defences and large numbers of ostertagia may rapidly complete their development. This results in gut damage and the sudden onset of profuse watery diarrhoea. This problem may be more common where parasite control in young stock is poor, with resulting high levels of worm egg contamination of the pasture. There are other causes of scouring in cows after calving including salmonellosis, which is a very severe disease. All cases of sudden severe scouring in cows after calving should be investigated by a veterinarian. • Acute post calving mastitis may also be a severe and life-threatening disease. It is caused by a variety of bacteria and appropriate antibiotic treatment must be used. It is imperative to seek veterinary advice The incidence of all these diseases may be higher in cows tlftt are induced to(<j calve early.