Oocysts In Samples Research Articles

Protozoan Parasites in Adult Dairy Small Ruminants and Potential Predictors for Their Presence in Faecal Samples.

There is a scope to study protozoan infections in adult ewes and does, as these animals can act as reservoirs of infection for lambs and kids, for which these pathogens are harmful. The objectives of this study were to describe the prevalence of protozoan infections in faecal samples from adult sheep and goats on dairy farms across Greece and to evaluate farm-related factors potentially associated with the presence of protozoan infections in these animals. A cross-sectional study was performed on 325 sheep and 119 goat farms throughout Greece; faecal samples were collected from ewes and does and processed for the identification of protozoan parasites. Eimeria oocysts were found in faecal samples from 69% of farms (72% of sheep farms and 61% of goat farms), Giardia cysts in samples from 33% of farms (33% of sheep farms and 34% of goat farms) and Cryptosporidium oocysts in samples from 8% of farms (7% of sheep farms and 11% of goat farms). In a multivariable analysis, for the presence of Eimeria in samples from sheep farms, the lack of a designated building for lambs emerged as a significant factor; for the presence of Giardia in samples from goat farms, the availability of a main building for animals emerged as a significant factor; for the presence of Cryptosporidium, the lack of grazing and the management system emerged as the main significant factors in sheep and goat farms, respectively. Protozoa were found significantly more frequently in samples collected from farms on which farmers considered diarrhoea as an important health problem in their lambs/kids.

Occurrence of eggs and oocysts of gastrointestinal parasites in passerine birds kept in captivity in Para State, Brazil

ABSTRACT: The objective of this study was to detect helminth eggs and protozoan oocysts in samples of feces from birds of the order Passeriformes in Para State, Brazil. Fecal samples were collected individually from 403 passerine birds seized and kept in captivity in Para State. Samples were processed by the double centrifugation technique in saturated sucrose solution and the coccidial oocyst-positive samples were submitted to sporulation in potassium dichromate 2.0%. Helminth eggs and/or protozoan oocysts were observed in 43.18% (174/403) of the fecal samples examined. Coccidial oocysts were detected in 93.68% (163/174) of the positive samples, whereas helminth eggs were observed in 10.34% (18/174) of the positive samples. Oocyst sporulation occurred in 43.56% (71/163) of the samples, and only Isospora spp. oocysts were detected. Nematode eggs of the superfamilies Trichostrongyloidea (4.60%; 8/174), Ascaridoidea (0.57%; 1/174), and Trichuroidea (0.57%; 1/174) were diagnosed in the positive samples. Cestoda eggs were diagnosed in 2.87% (5/174), whereas Trematoda eggs were detected in 2.30% (4/174) of positive samples. Passerine birds seized and kept in captivity in the visited local presented parasitism by intestinal helminths and protozoan, with a predominance of infection with coccidia of the gender Isospora.

FREQUÊNCIA DE ENTEROPARASITOS EM AMOSTRAS DE FEZES DE CÃES EM UM MUNICÍPIO DO PONTAL DO TRIÂNGULO MINEIRO, MINAS GERAIS, BRASIL

Dogs are considered important reservoirs of intestinal parasites due to their coprophagic behavior and close interaction with humans. The objective of this study was to determine the prevalence of Giardia spp. cysts and of coccidia oocysts in dog stool samples collected at the Zoonosis Control Center (CCZ) and at pet shops in Ituiutaba town, in the state of Minas Gerais, Brazil. Eighty stool samples (40% puppies and 60% adult dogs) were collected from dogs of both genders in individualand collective kennels. Cysts were then isolated from the samples using Sheather’s solution, and the oocysts were isolated in accordance with a modified version of the protocol by Ortega-Mora (1999). Thirty-four (42.5%) of dog samples were found to be positive for Giardia spp., 26 (51.0%) of which came from the CCZ, and 8 of which (27.6%) came from the pet shops. There was a prevalence of 13.72% (7) of oocysts in stool samples of CCZ dogs, and of 34.48% (10) oocysts in pet shop animals. The high prevalence of Giardia spp. cysts and oocysts in the samples may be associatedwith exposure to parasites from stray dogs. Clustering of animals in collective kennels or pet shops promotes the risk of intestinal parasite transmission with high zoonotic potential for the animals and for the people living with them.

Detection of Giardia and Cryptosporidium cysts/oocysts in watersheds and drinking water sources in Brazil urban areas

The protozoan parasites Giardia and Cryptosporidium have been described as important waterborne disease pathogens, and are associated with severe gastrointestinal illnesses. The objective of this paper was to investigate the presence of Giardia cysts and Cryptosporidium oocysts in samples from watershed catchments and treated water sources. A total of 25 water samples were collected and examined according to the US EPA--Method 1623, 2005, consisting of 12 from drinking water and 13 from raw water. Positive samples from raw water for Giardia cysts and Cryptosporidium oocysts were 46.1 and 7.6%, respectively. In finished water, positive samples were 41.7% for Giardia cysts and 25.0% for Cryptosporidium oocysts. Concentrations of Giardia cysts found in raw water samples ranged from "not detected" to 3.4 cysts/L, whereas concentrations of Cryptoporidium oocysts ranged from "not detected" to 0.1 oocysts/L. In finished water, Giardia concentrations ranged from "not detected" to 0.06 cysts/L, and Cryptosporidium, from "not detected" to 0.01 oocysts/L. Concentrations of Giardia cysts and Cryptosporidium oocysts were not high in the samples analyzed. Nevertheless, the results of this study highlight the need to monitor these organisms in both raw and drinking water.

Immunomagnetic separation of Toxoplasma gondii oocysts using a monoclonal antibody directed against the oocyst wall

Recent outbreaks of waterborne toxoplasmosis have stimulated the development of sensitive methods to detect Toxoplasma gondii oocysts in samples suspected to be contaminated. The immunomagnetic separation (IMS) have been standardised to detect waterborne protozoa, but it did not exist for Toxoplasma oocysts. In this study, we describe two monoclonal antibodies (mAbs 3G4 and 4B6) produced against the oocyst wall, and the incorporation of mAb 3G4 in an IMS procedure. We found that an indirect IMS method gave better mean recoveries than a direct one (69.4% and 25.2%, respectively). Dissociation of oocyst_magnetic bead complexes was greatly improved by using a 2% aqueous H 2SO 4 solution instead of a 0.1 N HCl solution (82.8% and 17.4%, respectively). With these parameters, mean recoveries of less than 1000 oocysts ranged from 44.6% to 82.9%, depending on incubating temperature and buffe r. Age of oocysts (1 or 12 months old) does not influence IMS performances. Results of this study indicate that the described IMS is an efficient technique to recover Toxoplasma oocysts.

Contamination of bivalve molluscs by Cryptosporidiumoocysts: the need for new quality control standards

A yearlong study was carried out to investigate the presence and viability of Cryptosporidium oocysts in 203 samples of cultured shellfish from Galicia (NW Spain) and 38 samples imported from other European Union (EU) countries. Shellfish samples included mussels, oysters, clams and cockles. Cryptosporidiumoocysts were detected, using a direct immunofluorescence antibody test (IFAT), in 34.4% of the samples analyzed; use of the fluorogenic dye propidium iodide (PI) revealed viable potentially infective oocysts in 53.0% of these samples. There was no relation between the presence of Cryptosporidium oocysts and the microbiological contamination detected in the samples expressed as Most-Probable-Number (MPN) of fecal coliforms, the different species of mollusc, or the month of sampling. One important finding was that the depuration process was ineffective in totally removing oocyst contamination. Furthermore, the existence of viable oocysts in samples with microbiological contamination levels lower than 300 fecal coliforms/100 g, which in accordance with current legislation are considered suitable for human consumption, suggests the need to include parasitological analyses in the quality control for these molluscs.

A novel method for counting eimerian oocysts at very low concentrations in aqueous suspensions

A novel method for counting eimerian oocysts in samples of drinking water has been developed to fulfil the need for monitoring the delivery of very low concentrations of live anticoccidial vaccines to poultry via pipeline nipple-drinker systems. Advantages of the method are the ease of sample collection and processing, high degrees of accuracy and precision, and a sensitivity of one oocystml−1. Results of a validation test are presented, with a protocol for the method and notes on its use. The coefficient of variation (CoV) of 10 sets of oocyst counts with nominal means of 10 to 160 oocysts ml−1ranged from about 16 per cent down to 6 per cent. The recovery efficiency for all 100 validation counts averaged 100·2 per cent with a range of 70–130 per cent. A practical example of field use of the method is given, including a modification to decrease the time taken for counting. In this case, when oocysts were pumped around a pipeline circuit of 129m for 2·5 hours, the CoV of a mean of 112 oocysts ml−1(n = 10) was 12·4 per cent.

Molecular Characterization of Cryptosporidium Oocysts in Samples of Raw Surface Water and Wastewater

Recent molecular characterizations of Cryptosporidium parasites make it possible to differentiate the human-pathogenic Cryptosporidium parasites from those that do not infect humans and to track the source of Cryptosporidium oocyst contamination in the environment. In this study, we used a small-subunit rRNA-based PCR-restriction fragment length polymorphism (RFLP) technique to detect and characterize Cryptosporidium oocysts in 55 samples of raw surface water collected from several areas in the United States and 49 samples of raw wastewater collected from Milwaukee, Wis. Cryptosporidium parasites were detected in 25 surface water samples and 12 raw wastewater samples. C. parvum human and bovine genotypes were the dominant Cryptosporidium parasites in the surface water samples from sites where there was potential contamination by humans and cattle, whereas C. andersoni was the most common parasite in wastewater. There may be geographic differences in the distribution of Cryptosporidium genotypes in surface water. The PCR-RFLP technique can be a useful alternative method for detection and differentiation of Cryptosporidium parasites in water.

Species of Eimeria of small wild rodents from the British Isles, with descriptions of two new species

An examination of oocysts in samples and isolates originating from the faeces or gut contents of 582 wild wood-mice (Apodemus sylvaticus), yellow-necked mice (A. flavicollis) and bank-voles (Clethrionomys glareolus) revealed 7 different species of the genus Eimeria. Of these, E. divichinica Musaev & Veisov, 1963, E. apodemi Pellerdy, 1954 and E. hungaryensis Levine & Ivens, 1965 are recorded from British wood-mice, and E. rysavyi Levine & Ivens, 1965 from British bank-voles for the first time. Two additional species from the wood-mouse, E. montgomeryae n.sp. and E. uptoni n.sp., are described. The species E. divichinica, E. apodemi, E. hungaryensis and E. uptoni were also found in the yellow-necked mouse. The pre-patent times of E. apodemi, E. hungaryensis, E. montgomeryae and E. divichinica were established by passage in the wood-mouse. ac]19820916