Zur Morphologie von Strongylus vulgaris (Nematodes)

Ultrastructural aspects of feeding and secretion–excretion by the equine parasite Strongylus vulgaris

“…The present data confirm and extend earlier findings on the 4th-stage larva and adult S. vulgaris and agree with the description of the S-E system (tubules and glands) (Enigk & Grittner, 1952). The S-E system of S. vulgaris is of the rhabditoid type (Chitwood & Chitwood, 1974) and its ultrastructural morphology is very similar to that described for other nematodes especially the hookworm, Necator americanus (McLaren, 1974).…”

“…In the S-E system of both the 4th-stage larva and adult S. vulgaris, as studied by light microscopy, the tubules and glands differ from those described for other nematodes in that transverse sections reveal a pair of S-E canals in each lateral cord, i.e. a straight canal and a winding one (Enigk & Grittner, 1952). The winding canal starts blindly midway between the nerve ring and the anterior tip of the nematode and winds backward in the lateral cord toward the tail, where it joins the straight canal just before the anal opening.…”

“…Secretory-excretory glands vary in size, being largest in the 4th-stage larva during the active migratory phase, and it was suggested that gland granules are end products of metabolism. Proteolytic enzyme activity was not detected in medium containing 200 dissected S-E glands titrated in Tyrod's solution at pH 4.5 and 7.5 (Enigk & Grittner, 1952). The present study employed scanning and transmission electron microscopy to further investigate feeding, and S-E and related structures and processes, with special reference to possible sources of the ESP.…”

Studies on "Haemixodovin", the Pigment in the Eggs of the Cattle Tick Boophilus Microplus(Acarnia: Ixodidae)

“…Therefore, while a small proportion of the egg haematin may be used in the construction of larval haematin enzymes, or in cuticle pigmentation, circumstantial evidence indicates that, in the main,only the protein portion of the haemixodovin molecule is utilized by the larva as a reserve food, the discarded haematin being left as a deposit in the larval gut. None of this deposit is excreted as faeces while the larva remains unfed, but Enigk and Grittner (1952) have described the evacuation of reddish black faeces by ixodid larvae after they had attached to a host and commenced blood sucking. These authors explain this delayed evacuation of faeces on anatomical grounds.…”

“…This decrease in haemoprotein was accompanied by a very slight decrease in the corresponding haematin concentrations. During the incubation of unfed larvae, deposits of ivory-coloured urinary excreta, predominantly guanine (Enigk and Grittner 1952), collected on the walls of the sample tubes. No pigment could be extracted from this solid excreta by sodium hydroxide solution.…”