Gregarine and coccidian protozoans (Apicomplexa) found leading to hypertrophy of the digestive epithelial cells and nephridal tubules, respectively, were recorded only in the Mar del Plata population, both with a low prevalence and intensity of infection (Table 2).
The investigator assigned this phenomenon to a parasitic infestation and went on to describe a new
gregarine species, Diplodina gonadipertha (Djakonov, 1923).
One popular alternative hypothesis for the pattern of invasion and decline is apparent competition via the
gregarine protozoan parasite Ascogregarina taiwanensis (Blackmore et al.
These included, for mytilid taxa, the
gregarines, ciliates, prokaryotic inclusions, trematode metacercariae, coccidians, copepods, xenomas [cells distended with numerous gill ciliates as described in Otto et al.
Quantitative scores were used for parasites and pathologies, including prokaryotic inclusions (Rickettsia, Chlamydia, etc.), ciliates,
gregarines, nematodes, cestodes, and metacercariae of trematodes, that could be tallied individually, following procedures described by Ellis et al.
Hammonasset East Tom's River River Creek VGH 0.35 0.82 0.00 RLOs 6.27 8.20 8.46 Ciliates 5.23 2.05 0.00 Xenomas 0.35 1.23 0.00 SG 0.70 0.41 0.00 Haplosporidium 22.65 5.74 24.89 nelsoni Nematopsis 5.23 2.05 0.00 Turbellaria 2.09 1.23 0.00 Hexamita 0.00 1.63 0.00 Mecox Pawcatuck Bay VGH 0.00 4.00 RLOs 4.17 8.00 Ciliates 0.00 0.00 Xenomas 0.00 0.00 SG 0.00 8.00 Haplosporidium 0.00 0.00 nelsoni Nematopsis 0.00 0.00 Turbellaria 0.00 0.00 Hexamita 0.00 0.00 VGH, viral gametocyte hypertrophy; RLOs, rickettsia-like organisms; SG, Sprague's
Gregarines.
It was reported that
gregarines of the genus Nematopsis cause focal hemocytic infiltration at most, without obvious pathogenic effects (Bower et al.
Gregarines del genere Nematopsis (Apicomplexa: Porosporidae) in Molluschi bivalvi del mare Adriatico.
Gregarines of the genus Nematopsis use marine bivalves as normal intermediate hosts, completing their life cycle in the gut of marine arthropods, and are usually associated with a focal hemocyte infiltration, without measurable effects on host health (Lauckner 1983).
Three new species of
gregarines (Apicomplexa: Sporozoea: Porosporidae) in the estuarine crab from Kerala, India.
Excluding the numerically-dominant
gregarines, however, removed the differential between oysters and mytilids, with the exception of East-coast mytilids that were more frequently parasitized than East-coast oysters.
In addition, Cremonte and Figueras (2003) reported, for the first time for this species, coccidian and
gregarines in a sample of yellow clam from Isla del Jabali, which was taken 2 years before the mass mortality.
albopictus is competent for dengue serotypes 2 and 3 in Mexico (16), its current geographical distribution, relative population of host-seeking females and the possible existence of parasitic
gregarine in northeastern Mexico have not been documented.
Previous studies demonstrated an association between the number of B chromosomes and resistance to
gregarine infection in natural populations of this species (Gorlov & Tsurusaki 2000).
