Menacanthus stramineus

Menacanthus stramineus

Summary

Type: Chewing Lice

Zoonotic: No

Definitive Hosts: Birds

Inf Site: Skin (Epidermis)
Dx Tech: Direct Observation
Dx Stage: Adult with 6 Legs, Nymph with 6 Legs, Eggs("nits") on Hairs
Size: Macroscopic
Tran Mode: Direct Contact

Life Cycle

Lice undergo an incomplete metamorphosis which takes place entirely on the host within a period of 3-5 weeks. The eggs, commonly called "nits", are glued to the feathers of the host. The young lice develop through several nymphal stages, during which they look like small, pale adults. Nymphs and adults are transmitted from one animal to another primarily by host contact.

Taxonomy

Phylum Arthropoda
Class Insecta
Order Mallophaga
Suborder Amblycera

Diagnosis

Restlessness and anemia are two of the most outstanding clinical signs that should suggest pediculosis. Adults are small (up to 3.3 mm in length), with heads which are rounded anteriorly. The mouthparts are ventral and the claws are small. Careful examination of the skin and feathers of infested animals will reveal yellowish lice and their eggs which have distinctive filaments on the operculum and anterior half of the shell. Nits are laid in clusters.

Clinical Information

Chewing lice feed by nibbling on the feathers and epidermal debris, although some of them ingest blood by piercing the pulp of feathers or gnawing through the epidermis. Chewing lice annoy their hosts primarily by irritating the skin surface. A few lice are generally well tolerated, whereas large numbers may cause severe irritation, resulting in self-trauma. In general, lice are much more of a problem in young or debilitated animals than in older, well-nourished animals. A heavy louse infestation may itself be merely a symptom of some other underlying condition, such as malnutrition or chronic disease; debilitated animals often do not groom themselves and leave the lice undisturbed. 

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