Energy and Food Reserves in the Development of Nematodes

The Physiological Ageing of the Infective Larvae of Haemonchus contortus

“…However, many workers have investigated the physiological ageing of Ancylostome larvae and the results should a PPtyi to some extent, to Trichostrongyle larvae. Thus Payne (1922and .1923), Cort (1925 and later Giovannola (1936) have shown that the physiological age of infective Ancylostome larvae can be determined by the examination of the fat stored in them. Rogers (1939) has determined the relationship between fat content, activity and infectivity in third stage hookworm larvae ageing under controlled conditions and the aim of the present work has been to find the similar relationships in Trichostrongyle larvae as exemplified by Haemonchus contorlus.…”

Intestinal granules found in the parasitic nematodes Ancylostoma caninum, and Oesophagostomum radiatum

“…Tornquist hypothesized that a direct association existed between granules and ingested blood. Giovannola (1936) noted the same relationship. He observed 'black, residual substances' in the intestinal lumen of Ancylostoma and Necator hookworms, however none were found in the Ascaris lumbricoides worm.…”

“…CaS. Giovannola (1936) It was impossible to determine in this experiment if intestinal granules within Ancylostoma caninum increased in number with the age of the worms. The nematodes were collected on the ninth week of culturing within their canine host, during which time the dog had to be sacrificed.…”

Anaerobiosis in invertebrates

“…Glycogen and paraglycogen are unquestionably important reserve substances for the anaerobic metabolism of parasitic protozoa, although usually only the storage of these substances and not their actual consumption has been demonstrated. It has thus been shown that the flagellates Giardia and various trichomonads accumulate considerable glycogen reserves (Deschiens, 1924;Giovannola, 1934;Stewart, 1938;Stewart-Lyford, 1941) and that glycogen or paraglycogen occurs in parasitic ciliates like Balantidium, Opalina and Nyctotherus (Biitschli, 1887;Barfurth, 1885;Jirovec, 1926;Kedrowsky, 1931;Armer, 1944).…”

“…A considerable polysaccharide storage has been reported for Coccidia and for Gregarines (Brault and Loeper, 1904b;Giovannola, 1934;Joyet-Lavergne, 1926; Edgar, Herrik and Eraser, 1944), but it has not yet been demonstrated that these carbohydrates are consumed under anaerobic conditions. M e s o z a .…”