Sustained-release delivery systems and their application for endoparasite control in animals
M Cardamone1, R P Lee, J C Lucas
1Centre for Animal Biotechnology, School of Veterinary Science, University of Melbourne, Parkville, Victoria, Australia. michaelc@gmp.usyd.edu.au
Summary
A novel solid moxidectin formulation in a sustained-release device offers superior protection against Haemonchus contortus in sheep. This advanced delivery system reduces anthelmintic dosage and extends parasite control for livestock.
Area of Science:
- Veterinary Parasitology
- Pharmacology
- Animal Science
Background:
- Macrocyclic lactones, like moxidectin, are potent anthelmintics used in livestock.
- Current injectable formulations require frequent administration.
- Developing sustained-release systems can improve efficacy and reduce treatment frequency.
Purpose of the Study:
- To evaluate a novel solid formulation of moxidectin delivered via a non-degradable device in sheep.
- To assess the anthelmintic efficacy and duration of protection against Haemonchus contortus.
- To compare the efficacy of the sustained-release formulation with a commercial injectable moxidectin product.
Main Methods:
- A solid moxidectin formulation was loaded into a subcutaneous delivery device for sheep.
- In vivo efficacy was monitored using fecal egg counts after Haemonchus contortus challenge.
- Antibody levels were measured in sheep with repeated larval infections.
Main Results:
- The solid moxidectin formulation provided greater protection against Haemonchus contortus than injectable Cydectin at the same dose.
- Anthelmintic dosage could be reduced to 1/6 of the recommended injectable dose.
- A single administration with two pellets extended Haemonchus contortus control from 42 to 183 days.
- Moxidectin-loaded devices significantly reduced antibody levels, indicating reduced antigenic load.
Conclusions:
- Sustained-release moxidectin via a non-degradable device is a highly effective anthelmintic strategy for sheep.
- This approach allows for reduced dosage and prolonged parasite control, potentially for an entire season.
- The technology may significantly improve nematode disease management in livestock with a single application.
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