Gelatin treats containing filamentous fungi to promote sustainable control of helminths among pets and zoo animals

[Display omitted] •Helminths can affect almost all grazing animals, and up to 80% pets.•Ingestion of certain fungi helps in reducing the risk of infection by helminths.•Gelatins with fungi are easily prepared and dehydration guarantees long durability.•Gelatins and dry gelatins are useful in halving the risk of helminthoses. The appropriateness of edible formulations of the parasiticide fungi Mucor circinelloides (ovicide) and Duddingtonia flagrans (larvicide) for the control of helminths affecting animals has been tested in two assays. Firstly, gelatin-based treats were manufactured with a blend of 3 – 6·107 chlamydospores each fungus and provided to three groups of six puppies each passing eggs of Toxocara canis, thrice a week for eight weeks. Feces collected at the end of this period were analyzed during four weeks to estimate the egg viability, the counts of infective eggs and the soil contamination index. The usefulness of the edible formulation comprised checking for the easiness of preparation and administration, the level of acceptance by the targeted animals and the expiration interval. A similar assay was conducted on a group of six captive baboons, but some refused to ingest the gelatins and others did it with difficulty. The second assay consisted of drying the gelatin treats and administering (thrice a week for eight weeks) to other two groups of six pups each infected by T. canis (different from those in assay I), and to six baboons captive in a zoo and passing eggs of Trichuris sp. (this probe on baboons was performed in triplicate at a four-month interval). Feces collected after eight weeks were examined for four weeks as mentioned previously. Viability of eggs of T. canis was significantly halved with the two edible formulations, and 44% reached the infective stage. In the feces of baboons taking dry gelatins, 50% eggs of Trichuris sp. remained viable, and 14% attained infectivity. Soil contamination by these nematodes was 20 and 5%, respectively. It was concluded that gelatin treats containing chlamydospores of a blend of M. circinelloides and D. flagrans offer a highly effective and practical formulation to develop strategies for the biological control of helminths affecting pets. In addition to retaining the high helminthicidal activity, the dehydration of the gelatins provides a very safe edible formulation, easy to store at room temperature and to give to companion animals and captive wild species, thus its administration is strongly