− | Cyathostomins are also known as small strongyles, and are one of the most important gastro-intestinal parasites of the horse. Over 40 species and several genera have been identified. The small, thread-like worms inhabit the caecum and the large colon with their developmental stages confined to the mucosa of the large intestine. Unlike the large strongyles, they do not undergo any extra-intestinal migration during development. Larvae ingested may develop to the L4 stage without interruption, leading to the characteristic 'pepper-pot' mucosal lesions seen with this type of disease. Larval emergence may occur throughout the summer and autumn, leading to the clinical signs associated with a 'wormy' horse however some larvae may become arrested at the EL3 stage. It is the mass, synchronous emergence of these hypobiotic larvae that leads to the clinical disease of larval pr Type 2 cyathostomosis. | + | Cyathostomins are also known as small strongyles, and are one of the most important gastro-intestinal parasites of the horse. Over 40 species and several genera have been identified. The small, thread-like worms inhabit the caecum and the large colon with their developmental stages confined to the mucosa of the large intestine. Unlike the large strongyles, they do not undergo any extra-intestinal migration during development. Larvae ingested may develop to the L4 stage without interruption, leading to the characteristic 'pepper-pot' mucosal lesions seen with this type of disease. Larval emergence may occur throughout the summer and autumn, leading to the clinical signs associated with a 'wormy' horse (type 1 cyathostomosis). However, some larvae may become arrested at the EL3 stage and it is the mass emergence of these hypobiotic larvae that leads to the clinical disease of larval or Type 2 cyathostomosis. |
− | All horses may be affected but most are less than five years old. Disease commonly occurs in late winter or early spring. | + | All horses may be affected but most are less than five years old. Disease commonly occurs in late winter or early spring. A history of an unthrifty or 'poor do-ing' young horse combined with identifcation of larvae in faeces may arouse clinical suspicion of cyathostomosis. |