Brand: VIRBAMEC ® ORAL
Company: VIRBAC
FORMULATION: «drench» for oral administration.
ACTIVE INGREDIENT(S): Abamectin: 0.8 g/L (=0.08%)
CHEMICAL CLASS of the active ingredient(s): macrocyclic lactone
INDICATIONS: SHEEP
PARASITES CONTROLLED (spectrum of activity)
- Roundworms:
- Gastrointestinal roundworms (adult and 4th-stage larvae): Ostertagia = Teladorsagia circumcincta (incl. inhibited larvae), Haemonchus contortus, Trichostrongylus axei, Trichostrongylus colubriformis, Trichostrongylus vitrinus, Nematodirus spathiger, Nematodirus filicollis, Cooperia curticei, Cooperia oncophora, Oesophagostomum columbianum, Oesophagostomum venulosum, Strongyloides papillosus, Chabertia ovina, Trichuris ovis.
- Lungworms: of Dictyocaulus filaria.
- Gastrointestinal roundworms (adult and 4th-stage larvae): Ostertagia = Teladorsagia circumcincta (incl. inhibited larvae), Haemonchus contortus, Trichostrongylus axei, Trichostrongylus colubriformis, Trichostrongylus vitrinus, Nematodirus spathiger, Nematodirus filicollis, Cooperia curticei, Cooperia oncophora, Oesophagostomum columbianum, Oesophagostomum venulosum, Strongyloides papillosus, Chabertia ovina, Trichuris ovis.
- Nasal bots, Oestrus ovis, all larval stages.
- Itch mites, Psorergates ovis.
RECOMMENDED DOSE
- 1 ml product/4 kg bw, equivalent to: abamectin 0.2 mg/kg bw
SAFETY
- LD50 (acute oral) in rats: abamectin a.i. 1.5 mg/kg (according to MSDS)
- LD50 (acute dermal) in rats: abamectin: a.i. >330 mg/kg (according to MSDS)
- Estimated hazard class according to the WHO: not applicable for veterinary medicines
Suspected poisoning? Read the articles on abamectin safety in this site.
Withholding periods (=withdrawal times) in days for meat & milk (country-specific differences may apply: read the product label)
- Meat: Australia 14 days (ESI 28 days)
- Milk for human consumption: DO NOT USE in dairy animals producing milk for human consumption or within 28 days prior to lambing.
WARNING !!!: Never use on humans, dogs or cats
You may be interested in the following articles in this site dealing with the general safety of veterinary products:
- Safety for humans
- Safety for domestic animals
- Safety for the environment
- Hazard classifications of pesticides
RESISTANCE PREVENTION
Risk of resistance of gastrointestinal roundworms to macrocyclic lactones (incl. abamectin): YES, resistance in ruminants is a very serious and increasing problem worldwide, particularly in sheep and goats. The most affected worm species are: Haemonchus spp, Ostertagia spp /Teladorsagia spp, Trichostrongylus spp, Nematodirus spp, Chabertia ovina.
Resistance of gastrointestinal roundworms to macrocyclic lactones (incl. abamectin) in sheep, goats and cattle has been reported almost worldwide, including the USA, UK, Australia and New Zealand. Based on the very abundant and frequent use of ivermectin and other macrocyclic lactones (with cross-resistance to ivermectin) in livestock it must be assumed that resistance of these roundworms to this chemical class will continue spreading and strengthening in the future.
Alternative chemical classes/active ingredients to prevent resistance of gastrointestinal roundworms through product rotation:
- Benzimidazoles, e.g. albendazole, febantel, fenbendazole, oxfendazole, etc. Similar or even worse resistance problems than ivermectin
- Imidazothiazoles, mainly levamisole. etc. Similar or even worse resistance problems than ivermectin
- Monepantel: available only for sheep & goats in some countries (e.g. Australia, UK & EU, New Zealand). First cases of resistance reported in New Zealand in 2013.
- Nitroxinil (limited spectrum of activity)
- Tetrahydropyrimidines, e.g. morantel, pyrantel (limited spectrum of activity)
- Salicylanilides, e.g. closantel (limited spectrum of activity)
These alternative products may not be available in all countries, or may not be available as drenches.
This means that if this product does not achieve the expected efficacy against the mentioned parasites, it may be due to resistance and not to incorrect use, which is usually the most frequent cause of product failure.
Learn more about resistance and how it develops.
MARKETING
Are the active ingredients of this product ORIGINAL* or GENERICS**?
- GENERICS
*Meaning that they are still patent protected and generics are not yet available
**Meaning that they have lost patent protection and may be acquired from manufacturers of generic active ingredients other than the holder of the original patent.
COUNTRIES where this brand/product is marketed: Australia.
GENERIC BRANDS available? Yes a few ones. This product itself contains generic abamectin.
Click here to learn more about GENERIC vs. ORIGINAL drugs.
For an overview on the most used antiparasitic pour-on brands click here.
COMMENTS
VIRBAMEC ORAL is an anthelmintic drench from VIRBAC containing abamectin. There is another formulation from VIRBAC (VIRBAMEC ORAL PLUS SE) with the same abamectin composition but with Selenium.
Abamectin, a veteran endectocide introduced in the 1980s (by MSD AgVet → MERIAL), is considered as the "cheap" macrocyclic lactone. It is less potent and more toxic than ivermectin and other macrocyclic lactones but is often "good enough", with a similar spectrum of activity as ivermectin. Interestingly abamectin is widely used in livestock and horses in Australia and New Zealand but so far not in the EU, the USA and Canada. As for other macrocyclic lactones, abamectin has no efficacy whatsoever against tapeworms and flukes.
In ruminants, reducing the amount of feed slows down the exit flow of the rumen and prolongs the time during which the active ingredient remains there and is absorbed. Consequently it is advisable to reduce the access of animals to feed (especially to fresh pasture, not to water) 24 hours before administration. For the same reason, it is better to keep the animals away from food for about 6 hours after drenching. However sick or weak animals should not be kept away from food and fasting animals should have access to water.
Click here for general information on good practices for the prevention and control of gastrointestinal worms in livestock.
DISCLAIMER
This article IS NOT A PRODUCT LABEL. It offers complementary information that may be useful to veterinary professionals and users that are not familiar with veterinary antiparasitics.
Information offered in this article has been extracted from publications issued by manufacturers, government agencies (e.g. EMEA, FDA, USDA, etc.) or in the scientific literature. No guarantee is given on its accuracy, integrity, sufficiency, actuality and opportunity, and any liability is denied. Read the site's DISCLAIMER.
In case of doubt contact the manufacturer or a veterinary professional.