Search results for "Parasite hosting"
showing 10 items of 306 documents
Drug Synergism: Studies of Combination of RK-52 and Curcumin against Rhodesain of Trypanosoma brucei rhodesiense
2020
Rhodesain is an enzyme essential for the life of Trypanosoma brucei rhodesiense, a parasite causing a rapid-onset form of Human African Trypanosomiasis. RK-52 is a synthetic inhibitor of rhodesain,...
A High Sensitive Nested PCR for Toxoplasma gondii Detection in Animal and Food Samples
2013
Toxoplasma gondii is a major food and waterborne transmitted parasite world-wide. The tissues and meat samples of many warm blooded animals can contain tissues cysts from chronic toxoplasmosis. Water and vegetable can be contaminated by the parasitic oocysts shed through the feces of infected cats, representing the definitive host of the parasite. A sensitive PCR for Toxoplasma gondii detection is described. The first step amplified the region between the 28S and 18S rDNA in the closely related T. gondii and Neospora caninum; RFLP analysis distinguished the DNA from the two morphologically identical parasites. Although N. caninum is not involved in human transmission, so far, it is importan…
Combining stable isotope and intestinal parasite information to evaluate dietary differences between individual ringed seals (Phoca hispida botnica)
2006
The diet and foraging behaviour of nine individual Baltic ringed seals ( Phoca hispida botnica Gmelin, 1785) in the Bothnian Bay were studied by combining results from stable isotope analyses (δ13C and δ15N) with data on intestinal parasites whose occurrence varied among the fish hosts. The patterns of infection with three acanthocephalan parasites, Corynosoma semerme (Forssell, 1904), Corynosoma magdaleni Montreuil, 1958, and Corynosoma strumosum (Rudolphi, 1802), and with a cestode larva, Schistocephalus solidus (Müller, 1776), were examined. The ringed seals become infected with these intestinal parasites by feeding on the fish hosts and hence have different parasite species and differe…
Shoaling behaviour of fish under parasitism and predation risk
2008
Shoaling is a common antipredatory adaptation in several fish species. However, parasite infections may alter shoaling behaviour of fish by impairing fish sensory/motor systems and by reducing the net benefit of shoaling. In an experimental study, we investigated whether Diplostomum spathaceum (Trematoda) eye flukes alter shoaling behaviour of rainbow trout, Oncorhynchus mykiss, and if this has an interaction with predation risk. The parasite reduces the vision of fish by inducing cataract formation, which in previous studies has been shown to alter fish escape responses and crypsis. We found that the shoals of infected fish contained fewer individuals and they divided into separate groups …
Myxosporea parasites in roach, Rutilus rutilus (Linnaeus), from four lakes in central Finland
1991
Ten myxosporean species belonging to three families were found in roach, Rutilus rutilus (Linnaeus), obtained in 1985 and 1986 from four lakes in central Finland which are connected to each other, but differ in water quality. One of the lakes is polluted by paper and pulp mill effluent, two are eutrophic and one is oligotrophic and still in its natural state. Eight species were found in all the lakes. The most common species were Myxidium rhodei Leger, 1905, Myxobolus muelleri Butschli, 1882 and Myxobolus pseudodispar Gorbunova, 1936 with prevalences varying between 66–80, 16–31 and 32–59%, respectively, in the four lakes. The largest difference in myxosporean prevalence between lakes was f…
Development and habitat selection of a new sanguinicolid parasite of cultured greater amberjack, Seriola dumerili, in the Mediterranean
2009
Abstract This study presents a description of the developmental stages of a new sanguinicolid disease agent (Paradeontacylix ibericus) of cultured Seriola dumerili (greater amberjack) in the Mediterranean, and investigates parasite habitat selection in the definitive host and the development of sanguinicolidosis in experimental, inshore cultures of S. dumerili . Two experimental surveys were carried out using fish captured as wild 0+ juveniles in the aquaculture facilities at Puerto de Mazarron (Spain). Encysted, early post-cercarial stages (schistosomula) were detected in histological sections of the pelvic and thoracic muscles of fish and four subsequent stages of parasite development wer…
The earliest evidence of host-parasite interactions in vertebrates
2009
Luk s evics, E., Lebedev, O. A., Mark-Kurik, E. and Karataj u te-Talimaa, V. 2009. The earliest evidence of host‐parasite interactions in vertebrates. — Acta Zoologica (Stockholm) 90 (Suppl. 1): 335‐343 Traces of parasite action have been discovered in the Middle‐Upper Devonian fish from Estonia, Latvia and European Russia. Such traces are known in heterostracan Psammolepis venyukovi , antiarchs Asterolepis radiata and Bothriolepis ciecere , sarcopterygians Holoptychius sp., Ventalepis ketleriensis and Eusthenodon sp. nov. The traces include evidence of parasitic fixation and penetration as well as dwelling traces. Pathologies are developed as (1) round fossulae on the external surface of b…
A long non-coding RNA controls parasite differentiation in African trypanosomes
2020
Trypanosoma bruceicauses African sleeping sickness, a fatal human disease. Its differentiation from replicative slender form into quiescent stumpy form promotes host survival and parasite transmission. Long noncoding RNAs (lncRNAs) are known to regulate cell differentiation. To determine whether lncRNAs are involved in parasite differentiation we used RNAseq to survey theT. bruceilncRNA gene repertoire, identifying 1,428 previously uncharacterized lncRNA genes. We analysedgrumpy, a lncRNA located immediately upstream of an RNA-binding protein that is akeydifferentiation regulator. Grumpy over-expression resulted in premature parasite differentiation into the quiescent stumpy form, and subse…
New distributional data on <em>Haemogregarina stepanowi</em> (Apicomplexa) and <em>Placobdella costata</em> (Hirudinea) paras…
2021
The host-parasite system “Emys trinacris – Placobdella costata – Haemogregarina stepanowi” is known for Sicily, but scarce information is available to date about the distribution of the two parasites on the island. Therefore, an extensive sampling effort through visual census and collection and analysis of blood smears of the endemic Sicilian pond turtle E. trinacris was carried out in 46 water bodies scattered throughout mainland Sicily. Our findings revealed that the distribution of both parasites is limited to the Nebrodi area, where the infection of H. stepanowi has shown a high incidence on the local turtle populations. Our data suggest no correlation between the current distribution o…
Cryptosporidium parvum: Structural Components of the Oocyst Wall
1999
Cryptosporidium parvum, an enteropathogenic parasite, infects a wide range of mammals including man and constitutes a substantial veterinary and medical threat due to its ubiquitous distribution and the stability of the oocyst stage. The oocyst wall of C. parvum is known to be extremely resistant to chemical and mechanical disruption. Isolated oocyst walls are shown by both thin sectioning and negative staining transmission electron microscopy to possess a filamentous array on the inner surface. This filamentous array can be greatly depleted by digestion with proteinase K and trypsin, but pepsin has less effect. Ultrasonication of the untreated oocyst walls produced almost no fragmentation,…