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It is a member of the trichostrongylodiea family and is responsible for parasitic bronchitis in cattle.
It is a member of the trichostrongylodiea family and is responsible for parasitic bronchitis in cattle.
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The penetration phase lasts one week and occurs when the larvae migrate to lungs. There are no clinical signs.
The penetration phase lasts one week and occurs when the larvae migrate to lungs. There are no clinical signs.
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Reinfection syndrome may occur if immune cattle are exposed to large numbers; only then will they show clinical signs.
Reinfection syndrome may occur if immune cattle are exposed to large numbers; only then will they show clinical signs.
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The disease is carried form year to year by overwintering L3 on pasture, as well as carrier animals. Knowledge of the full epidemiology of the disease is not yet understood. Calves pick up the overwintered L3 on pasture and a patent infection occurs producing L1 on the pasture. These migrate from the dungpat via fungus (Pilobolus) and the rest of the calves then become infected. There may be multiple cycles in one year. Immunity however, is rapidly acquired.
The disease is carried form year to year by overwintering L3 on pasture, as well as carrier animals. Knowledge of the full epidemiology of the disease is not yet understood. Calves pick up the overwintered L3 on pasture and a patent infection occurs producing L1 on the pasture. These migrate from the dungpat via fungus (Pilobolus) and the rest of the calves then become infected. There may be multiple cycles in one year. Immunity however, is rapidly acquired.
History and season, as well as clinical signs are very indicative of the disease.
History and season, as well as clinical signs are very indicative of the disease.
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A faecal examination for '''larvae''' using the Baerman technique, should be performed. Sick and healthy cattle should be tested.
A faecal examination for '''larvae''' using the Baerman technique, should be performed. Sick and healthy cattle should be tested.
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In adult cattle, a blood and milk ELISA can be used, however, this is of varying diagnostic quality.
In adult cattle, a blood and milk ELISA can be used, however, this is of varying diagnostic quality. Also in adult cattle, a retrospective diagnosis can be achieved by assessing the response to anthelmintic treatment.
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A post mortem can also be performed. The '''Inderbitzen technique''' can be used, which is where worms are flushed out of the lungs by pumping water through the pulmonary arteries. The water and worms are collected over a sieve. Worms are counted and 200-300 are required to cause clinical disease. Upon post mortem, one may also see pulmonary oedema and emphysema, which is thought to be caused due to a hypersensitivity response to a massive invasion of lungworm larvae.
A post mortem can also be performed. The '''Inderbitzen technique''' can be used, which is where worms are flushed out of the lungs by pumping water through the pulmonary arteries. The water and worms are collected over a sieve. Worms are counted and 200-300 are required to cause clinical disease. Upon post mortem, one may also see pulmonary oedema and emphysema, which is thought to be caused due to a hypersensitivity response to a massive invasion of lungworm larvae.
If the animal is clinically affected, treatment with anthelmintic such as ivermectin can be used.
If the animal is clinically affected, treatment with anthelmintic such as ivermectin can be used.
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Control of the disease can be achieved by strategic anthelmintic dosing such as invermectin being given 3, 8 and 13 weeks post turnout. There are limitations to this, such as is larvae are encountered early e.g. in the first 2 weeks after turnout or late in the grazing season.
Control of the disease can be achieved by strategic anthelmintic dosing such as invermectin being given 3, 8 and 13 weeks post turnout. There are limitations to this, such as is larvae are encountered early e.g. in the first 2 weeks after turnout or late in the grazing season.
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Vaccination, called 'Huskvac' is the control method of choice and prevents anthelmintic resistance aoccuring on farms. It should be given to first season calves that are reared indoors. The vaccine is oral and calves should be vaccinated 6 and 2 weeks prior to turnout. This results in the decreased clinical disease. The vaccine does not prevent infection completely, but reduces it enough to prevent clinical signs. Note; never mix vaccianted and unvaccinated animals.
Vaccination, called 'Huskvac' is the control method of choice and prevents anthelmintic resistance aoccuring on farms. It should be given to first season calves that are reared indoors. The vaccine is oral and calves should be vaccinated 6 and 2 weeks prior to turnout. This results in the decreased clinical disease. The vaccine does not prevent infection completely, but reduces it enough to prevent clinical signs. Note; never mix vaccianted and unvaccinated animals.