Tribamec Duo – targeting mixed parasite infections in sheep
Mixed parasite infections can present a real challenge in sheep – especially when multiple parasite life stages and the potential for resistance further complicates the picture.
Targeting all life stages with Tribamec Duo
Tribamec Duo can be useful when there is a need for fluke control as well as treatment for gut worms and or lungworm. Different life stages of these parasites can cause a variety of clinical pictures, so activity against all life stages is often important to achieve effective protection.
Triclabendazole – one of the active ingredients in Tribamec Duo - is the only one that treats all stages of liver fluke (Fasciola Hepatica), from adults down to immature flukes of one week of age. The other active ingredient – ivermectin, a member of the 3ML (clear) group of wormers – targets lungworm and common gut worms, including inhibited forms and those resistant to benzimidazoles (white drenches). It also treats all life stages of nasal bots (Oestrus Ovis).
Liver fluke (Fasciola Hepatica)
This trematode parasite (flat worm) is estimated to cost the Irish livestock industry at least €90 million, due to deaths, production losses (up to 30%) and condemned livers at slaughter.1 It is widespread, with data to suggest that over 60% of Irish sheep flocks will have liver fluke infections.2
Egg laying adults live in the liver of infected animals, with eggs being shed in the faeces onto pasture. Development into the infective form involves a species of mud snail and is weather and temperature dependant. Infective stages are eaten by sheep, migrate from the stomach to the liver and eventually develop into adults.
There are three different presentations of the disease (fasciolosis) caused by liver fluke:
- Acute: large numbers of infective fluke are eaten over a short period, most often in the spring. Flukes migrating through the liver cause severe damage and bleeding with sudden death the most common sign.
- Sub-acute: caused by a mixed infection of immature, late immature and adult life stages, generally occurs later in the year. Presents as severe depression, inappetence and weakness and has a huge effect on growth rate, milk yield, finish weights and body condition.
- Chronic: caused by adult flukes residing in the bile ducts. Presents as very poor condition, poor fleeces, anaemia and sometimes bottle jaw.
Gutworms
Ivermectin treats Haemonchus, Teladorsagia, Trichostrongylus, Cooperia, Nematodirus, Strongyliodes, Oesophagostomum and adult Chabertia ovina. All these worms can cause disease either on their own or in combination, however the most economically important in Ireland are Nematodirus, Telodorsagia and Trichostrongylus.
Disease is known as Parasitic Gastroenteritis (PGE) and is most commonly seen in animals under a year old (excluding Haemonchus which can affect any age). Adults can carry infection with no clinical signs, but they shed eggs which may overwinter on the pasture and infect the subsequent year’s lamb crop.
For some gut worm species, the larval stages can enter an ‘inihibited’ phase, where they stall development until conditions are more favourable. When this happens, mass emergence can cause disease with negative faecal egg counts, as there are no adult worms laying eggs.
Using Tribamec Duo responsibly
Triclabendazole is the optimal choice when it’s important that all stages of liver fluke are killed, or acute fasciolosis is a risk. Ivermectin is useful when inhibited larval forms of Haemonchus and Teladorsagia (Ostertagia) may be present, or there is resistance to benzimidazoles (1BZ white drenches).
Anthelmintic resistance is a serious concern for the Irish sheep industry and reports of resistance are increasing year on year. A recent study on 18 sheep farms in Ireland tested for resistance in the commonly used wormer groups:3
White 100%
Yellow 17%
Clear 16%
Triclabendazole resistance has also been reported, and as such should be used responsibly in rotation with other flukicides.2 A commonly used regime involves treating with closantel or nitroxynil in the spring and triclabendazole in the autumn/winter.2
Treatment plans should be tailored to each individual farm, depending on their risk profile. Treatments for mixed gut worm and liver fluke infections are usually required:
- In the early spring to target any flukes remaining in the liver of older animals and minimise pasture contamination from both fluke and overwintered/inhibited gut worms.
- In autumn, when numbers of immature fluke may be high, to present clinical disease due to acute fasciolosis.
Steps should also be taken to control parasites through pasture management whenever possible.
References:
1. https://www.teagasc.ie/news--events/daily/beef/the-successful-control-of-liver-fluke.php#:~:text=Liver%20fluke%20is%20estimated%20to,in%20meat%20and%20milk%20production.
2. Animal Health Ireland. Understanding Liver Fluke in Sheep Flocks
3. https://www.teagasc.ie/news--events/daily/sheep/control-and-treatment-of-stomach-worms-in-sheep.php
Tribamec Duo – targeting mixed parasite infections in sheep
Mixed parasite infections can present a real challenge in sheep – especially when multiple parasite life stages and the potential for resistance further complicates the picture.
Targeting all life stages with Tribamec Duo
Tribamec Duo can be useful when there is a need for fluke control as well as treatment for gut worms and or lungworm. Different life stages of these parasites can cause a variety of clinical pictures, so activity against all life stages is often important to achieve effective protection.
Triclabendazole – one of the active ingredients in Tribamec Duo - is the only one that treats all stages of liver fluke (Fasciola Hepatica), from adults down to immature flukes of one week of age. The other active ingredient – ivermectin, a member of the 3ML (clear) group of wormers – targets lungworm and common gut worms, including inhibited forms and those resistant to benzimidazoles (white drenches). It also treats all life stages of nasal bots (Oestrus Ovis).
Liver fluke (Fasciola Hepatica)
This trematode parasite (flat worm) is estimated to cost the Irish livestock industry at least €90 million, due to deaths, production losses (up to 30%) and condemned livers at slaughter.1 It is widespread, with data to suggest that over 60% of Irish sheep flocks will have liver fluke infections.2
Egg laying adults live in the liver of infected animals, with eggs being shed in the faeces onto pasture. Development into the infective form involves a species of mud snail and is weather and temperature dependant. Infective stages are eaten by sheep, migrate from the stomach to the liver and eventually develop into adults.
There are three different presentations of the disease (fasciolosis) caused by liver fluke:
- Acute: large numbers of infective fluke are eaten over a short period, most often in the spring. Flukes migrating through the liver cause severe damage and bleeding with sudden death the most common sign.
- Sub-acute: caused by a mixed infection of immature, late immature and adult life stages, generally occurs later in the year. Presents as severe depression, inappetence and weakness and has a huge effect on growth rate, milk yield, finish weights and body condition.
- Chronic: caused by adult flukes residing in the bile ducts. Presents as very poor condition, poor fleeces, anaemia and sometimes bottle jaw.
Gutworms
Ivermectin treats Haemonchus, Teladorsagia, Trichostrongylus, Cooperia, Nematodirus, Strongyliodes, Oesophagostomum and adult Chabertia ovina. All these worms can cause disease either on their own or in combination, however the most economically important in Ireland are Nematodirus, Telodorsagia and Trichostrongylus.
Disease is known as Parasitic Gastroenteritis (PGE) and is most commonly seen in animals under a year old (excluding Haemonchus which can affect any age). Adults can carry infection with no clinical signs, but they shed eggs which may overwinter on the pasture and infect the subsequent year’s lamb crop.
For some gut worm species, the larval stages can enter an ‘inihibited’ phase, where they stall development until conditions are more favourable. When this happens, mass emergence can cause disease with negative faecal egg counts, as there are no adult worms laying eggs.
Using Tribamec Duo responsibly
Triclabendazole is the optimal choice when it’s important that all stages of liver fluke are killed, or acute fasciolosis is a risk. Ivermectin is useful when inhibited larval forms of Haemonchus and Teladorsagia (Ostertagia) may be present, or there is resistance to benzimidazoles (1BZ white drenches).
Anthelmintic resistance is a serious concern for the Irish sheep industry and reports of resistance are increasing year on year. A recent study on 18 sheep farms in Ireland tested for resistance in the commonly used wormer groups:3
White 100%
Yellow 17%
Clear 16%
Triclabendazole resistance has also been reported, and as such should be used responsibly in rotation with other flukicides.2 A commonly used regime involves treating with closantel or nitroxynil in the spring and triclabendazole in the autumn/winter.2
Treatment plans should be tailored to each individual farm, depending on their risk profile. Treatments for mixed gut worm and liver fluke infections are usually required:
- In the early spring to target any flukes remaining in the liver of older animals and minimise pasture contamination from both fluke and overwintered/inhibited gut worms.
- In autumn, when numbers of immature fluke may be high, to present clinical disease due to acute fasciolosis.
Steps should also be taken to control parasites through pasture management whenever possible.
References:
1. https://www.teagasc.ie/news--events/daily/beef/the-successful-control-of-liver-fluke.php#:~:text=Liver%20fluke%20is%20estimated%20to,in%20meat%20and%20milk%20production.
2. Animal Health Ireland. Understanding Liver Fluke in Sheep Flocks
3. https://www.teagasc.ie/news--events/daily/sheep/control-and-treatment-of-stomach-worms-in-sheep.php