Latest news with #MauraLangan
Irish Examiner
29-05-2025
- Health
- Irish Examiner
Be alert to the risk of gut worms
HERD HEALTH SERIES: Maura Langan, Commercial and Technical Manager (Large Animal) at Norbrook. Maura Langan, Norbrook Veterinary Advisor. The warm, dry spell in March was welcomed by farmers and led to cattle being turned out earlier than usual. While we have had a healthy spring, farmers will need to factor in the early exposure to worms and a longer grazing period when dosing their cattle. Young calves are totally naive to parasites but will acquire some immunity as they are exposed to gut worms over time. As vets and farmers, we try to balance that exposure against the welfare and production losses associated with a significant worm burden. As a result, we tend to group animals according to risk. In a seasonal calving system like Ireland, that tends to be first grazing season (FGS), second grazing season (SGS) and adult cattle. Although there are around 20 types of gut worms that affect cattle, the two that are most economically important are Ostertagia and Cooperia. Over-wintered infective larvae are ingested soon after turnout and complete their lifecycle within the cattle before eggs are excreted back onto pasture. On dairy farms where cattle have only been housed for a couple of months and there have been few sustained frosts, it is likely that a significant number of viable larvae will have survived. Young FGS dairy calves are particularly vulnerable as they ingest more vegetation than suckler calves of the same age. Depending on the grazing pressure and level of contamination they may need anthelmintic treatment after only a few weeks. Clinical infections of parasitic gastroenteritis are often associated with scour, but it is the suppression of appetite that occurs in both clinical and subclinical cases that causes reduced growth rate. Parasitic infections can also lead to other developmental and fertility issues such as a delay in puberty, reduced conception rates and increased calving intervals. The decision when to dose and with what product, should be discussed with your vet. They will have a detailed knowledge of your farm, management system and its history. As well as being able to prescribe anthelmintics, they may undertake diagnostic tests such as faecal egg counts and recommend preventative grazing strategies. For FGS dairy or dairy-to-beef cattle, a key consideration will be the persistency of the product used. Some products, such as Taurador Pour-On or the new Taurador Injection protect against re-infection for up to 6 weeks after treatment. On farms where it may be difficult to bring cattle in to treat more regularly, this could be an appropriate strategy. The need for fewer worm doses can save both time and money, especially on busy dairy farms. Immunity to Ostertagia takes longer to build, so although SGS cattle may still need anthelmintic treatment, it may not be necessary until later into the summer. Products without persistency, such as Levacide Low Volume, may require more frequent retreatment but can be effective in allowing exposure to gut worms while checking the effects on production. Of course, the Irish climate may still have surprises for us, as our recent spell of warm weather looks set to change. Temperature does play a part in the hatching and development of worm larvae within the dung pat, but moisture is also required. In fact, rain plays an essential part in the distribution of larvae throughout the farm as faecal matter is through water flow and spread via transport hosts including cattle. For more information, visit HERE.
Irish Examiner
24-04-2025
- Health
- Irish Examiner
Be alert to the risk of grass tetany
HERD HEALTH SERIES: Maura Langan, Commercial and Technical Manager (Large Animal) at Norbrook Maura Langan, Norbrook Veterinary Advisor Grass tetany or staggers is a metabolic disease caused by an acute deficiency of magnesium (hypomagnesaemia). Lactating cows, especially those that are newly calved, have an increased requirement for magnesium. Most supplementary feeds will include adequate supplies of magnesium, but suckler cows and store cattle are rarely supplemented at grass and as such they may experience grass tetany. Cattle are unable store this essential mineral and have no active hormonal control of magnesium levels in the body, so they are reliant on daily dietary intake. Magnesium levels in pasture can vary quite considerably. The application of fertilisers containing nitrogen and potassium interferes with the uptake of magnesium by the grasses reducing the availability for cattle. Rapidly growing spring grass (especially rye grasses) is therefore low in magnesium, this is typically seen when a warm dry spell is followed by rain. Spring grass is also much lower in fibre which increases the rate of transit through the rumen, reducing magnesium absorption rates and causing scour. Poor weather, often a sudden cold and wet spell, is often associated with cases of grass tetany as cattle stop grazing and magnesium intake is further reduced. Clinical Grass Tetany is a rapid onset metabolic disease and a true veterinary emergency. Clinical signs include restlessness, hyper-excitability, 'wild eyes', frothing at the mouth, incoordination, staggering, collapse and seizures. Treatment needs to be instigated as soon as clinical signs are noticed, as animals will rapidly deteriorate and in severe cases death can occur within one hour of first symptoms. Emergency veterinary treatment is required with intravenous administration of a calcium and magnesium solution (Calciject 40+3) at first sign of symptoms. A further follow-up treatment of Magniject should be administered subcutaneously. Animals should not be stimulated during treatment. As with other metabolic conditions, animals that display clinical signs are only the tip of the iceberg and much of the herd is likely to be sub-clinically affected. Preventative measures via oral supplementation of magnesium are the simplest and most cost-effective option in managing grass tetany. Magnesium salts and minerals can be unpalatable. Mineral licks can be unreliable as individual intakes cannot be guaranteed. The optimum way of ensuring supplementation is through administration of a sustained release magnesium bolus. Opti-Mag3 bolus provides 100g of slow-release magnesium. Administration of two boluses 2-3 days before the risk period will supply approximately 6g of magnesium per animal per day for four weeks.
