Avermectin B1b is the minor component (<20%) of a commercially available anthelmintic used to control parasitic nematodes in livestock. Avermectin B1b contains a isopropyl residue in the 25-position. In vitro and in vivo studies have shown this analogue to be active, but less potent than the B1a analogue
ChEBI: Avermectin B1b is an avermectin.
(Merck)Avomec [Veterinary] (Merial); Bovitin
[Veterinary] (Merial); Doratect [Veterinary] (Merial);
Duomectin [Veterinary] (Merial); Duotin [Veterinary]
(Merial); Endecto (Merck); Enzec (Merck); Enzek
(Merck); Parafoil (Merck); Vertimil (Zectin
(Merck).
avermectin b1 is a mixture of avermectins containing >80% avermectin b1a and <20% avermectin b1b. b1a and b1b have very similar biological and toxicological properties.
the avermectins are insecticidal and antihelmintic compounds derived from various laboratory broths fermented by the soil bacterium. avermectin b1 is a natural fermentation product of this bacterium.
avermectin b1 therapy resulted in significant decreases in mean strongyle egg after treatment. all horses given ivermectin or avermectin b1 had zero strongyle egg counts 14 and 28 d after treatment. the oral administration of avermectin b1 appeared to be highly efficacious against intestinal strongyles and onchocera microfilaria [1].
[1] mogg td, pollitt cc, willmore jp, thompson h. efficacy of avermectin b1 given orally against equine intestinal strongyles and onchocera microfilaria. aust vet j. 1990;67(11):399-401.