جستجوی مقالات مرتبط با کلیدواژه « اووسیست » در نشریات گروه « دامپزشکی »

The protozoancryptosporidiumisan important intestinal parasitic infection in domestic ruminants that has the potential for transmission between humans and livestock throughout the world and Iran.

The present study was undertaken to determine cryptosporidiuminfection in different age groupsof cattle and water buffaloesin farms of Mahabad suburb, Iran.

For this purpose, a total number of 248 fresh fecal samples were randomly collected from rectum of cattle and water buffaloesin farms of 4 villages from May2016 to May 2017. The fecal samples were subjected to floatation technique andcryptosporidiumoocysts were collected using Sucrose Gradient and Percole flotation technique and stained with modified Ziehl-Neelsen technique.

Overall prevalence of cryptosporidiuminfection was 50% (124/248). The highest rate of infection was significant in female calves (30.65%) less than one year-old. The highest infection rate was significantly found in summer (20.16%). Cryptosporidium parvum and C. andersoni were identified in 40.32% (100/248) and 9.68% (24/248) of examined cattle, respectively. Mixed infection was 8.47%.

The results of this study indicated that C.parvum was prevalent in cattle of the region, therefore, further molecular studies are recommended to determine the genotypes of the parasiteas a potential zoonotic agent.

Eimeria infection is an important part of protozoal infection in ruminants which causes economic lost in animal husbandry of Iran and worldwide. Therefore it is important to implement effective control programs on the prevalence and diversity of Eimeria species in livestocks. This study was aimed to determine prevalence and Eimeria species diversity in dairy cattle with different age groups under industrial management. The present study was carried out in industrial cattle husbandry of Kangavar suburban of Kermanshah province, Iran, from spring 2011 to 2012. A total of 307 fresh fecal samples were randomly collected from the rectum of examined animals. The fecal specimens were subjected for flotation technique and collect Eimeria oocysts. The intensity of infection was determined using McMater method. Eimeria species diversity and frequency was also determined by using oocyst sporulation technique in 2.5% potassium dichromate. The overall prevalence was 31.92% (98 out of 307). The highest prevalence was found in dairy cattle (37%) with 1-3 years old. There was no significant difference between prevalence and different age groups. The highest frequency was significantly in spring (41.66%). The intensity was variable in examined animals which ranged from 3.18×103 to 2.71×105. There was no significant difference between the prevalence and intensity in all age groups. Fecal consistency findings revealed that the highest infection was significantly in dairy cattle with normal fecal consistency in all age groups. According to Laboratory identification, a number of seven Eimeria species were detected in all infected animals. The most common specie was E. zuernii (28.25%) in 5% dairy cattle (1-3 years-old) in spring (30%) and summer (30%). There was significant association between frequency of Eimeria infection and each season during the course of the study. All infected cattle had mixed infections with two (42.85%) and three (3.15%) species of Eimeria. The results of this study indicated that cattle Eimeria infection was a problem in dairy cattle of industrial farms in the region. Attention should be paid within seasonal infection in young cattle to avoid probable clinical coccidiosis, particularly in farms with poor hygienic conditions and no prophylactic treatments.

Cryptosporidium parvum is a protozoan parasite which belongs to apicomplexa phylum. The parasite infects both wild and domesticated animals and human beings as well. The purpose of the present study was to detect oocyst shedding and diarrhea pattern in experimental cryptosporidiosis and their correlation with weight loss in neonatal calves. Twelve Holstein calves of both sexes were obtained at birth from dairy farm and randomly divided into two groups of 6 calves. Six calves were orally infected with 107 C. Parvum oocysts at the 12h post parturition. The control group was not infected. Clinical signs were examined and fecal samples were collected by the rectal examination twice a day. All calves were weighed from day 0 to day 30 with 3 days intervals to determine effects of cryptosporidiosis on weight gain. All infected calves were noticeably depressed and had a decreased appetite from 3 days post inoculation (DPI) while they received colostrum. Subsequently، watery diarrhea with clumps of mucus and yellow or pale changes of feces color were observed. The infected calves have had diarrhea for 5-8 days that remarkably had got dehydrated. The most severity of diarrhea was 4-6 DPI. Oocyst excretion started 4 DPI، peaked at 6 DPI (60. 48×106±9. 03oocysts/g feces) and continued until 11 DPI. Control calves had no diarrhea and other clinical signs during the whole period of the trial. The mean weight gain of control group was significantly higher than inoculated group during experiment (p<0. 001). The Weight of the infected calves was retarded until 9 days old and then risen subsequently. Present study showed the role of C. Parvum as the primary cause of diarrhea and weight loss among neonatal calves.

Cryptosporidium baileyi is one of the pathogen protozoa which is specific for poultry. C. baileyi is able to infect، grow and reproduce in epithelial cells of respiratory، gastrointestinal and urinary tracts of chickens. This parasite has been isolated from Iran poultry industry. The aim of this study was to propagate the parasite in the chicken embryonating SPF eggs. Oocysts were maintained by passage through chicks. Faeces containing excreted oocysts were mixed with 2. 5% potassium dichromate (w/v) and stored at 4°C. Oocysts of C. baileyi were purified and cleaned by modification of Sheater’s sugar flotation method and using 1% sodium hypochlorite solution. The oocysts were washed with PBS and appropriate antibiotics were added. Ten day- old embryonating SPF eggs were inoculated via allantoic cavity with 1x 105 oocysts or equivalent oocysts exposed by excystation fluid. The eggs inoculated by samples were incubated 7 days at 37 ºC and candled once a day. The results showed that both inoculated samples were able to grow and propagate in chorio allantoic membrane and release the oocysts in allantoic fluid. Inoculation of 1x105 oocysts caused releasing of 1x106 oocysts in the allantoic fluid of one egg. Upon the results the propagation of C. baileyi in the chicken embryonating SPF eggs can be used in research works. This method can be used for limited propagation of the parasite using the intact oocysts as inoculated samples in embryonating eggs of chickens or even other birds..

The purpose of this study is to evaluate humoral immunity response in broiler chickens with mixed Eimeria infection، before and after treating by Salinomycin. The relation between the antibody titer and oocyst shedding was also investigated. Forty Ross 308 chicks were divided into 5 groups including 2 infected groups which had been fed with drug، 2 infected groups without treatment، and one as negative control. One of the infected groups was selected from Mazandaran (denoted as category1) and the other from Hamedan (denoted as category2). The antibody titer was assessed using ELISA test. In treated chickens of category 2، OPG (oocyst per gram) had a more significant difference (P≤ 0/05) than non-treated chickens of the same category. While in category 1، there was no significant difference for this index. The results showed more virulence in category 2 compared to category 1. There was a significant difference of OD (optical density) in the negative control group compared to the other four groups (P≤ 0/05). Both groups fed with oocysts showed stimulation of the immunity system to generate antibody، however its amount was not affected by Salinomycin. The results showed that there is no significant relation between oocyst shedding and antibody titers.

Coccidiosis is a common disease of poultry breeding industry in the world that cause by Eimeria spp. objective of the present study was comparison of anticoccidial effect of Diclazuril and Toltrazuril and their effects on the breeding function and intestinal oocyst shedding rate. Therefore, 300 broilers from Ross breed with 47 gr weigth average were divided into 3 groups randomely. Then chickens were inoculated 0.1 ml of suspension containing 10.000 Eimeria tenella oocysts in 22 days age and after produce coccidiosis in broilers, they were treated by Diclazuril and Toltrazuril through drinking water in two groups. Another group was untreated as control. Finally, food conception and intestinal oocyst shedding rate were compared with statistical analysis. Findings showed that difference between oocyst shedding rate in treated group with Diclazuril and control group (p=0.000) and treated group with Toltrazuril and control (p=0.000) were significant. But difference between two treated groups was not significant (p=0.059). Moreover, food conception rate in two treated groups were less than control group (p=0.000) that it indicated to better breeding function in treated groups. Therefore, regarding to similar effects of to anticoccidial compounds, it appears diclazuril is advised because of its lower dose and price.

Cryptosporidium parvum is a zoonotic protozoan which causes disease in immunocompromised patients and newborn animals especially calves. The oocysts excreted by infected animals are introduced into the environment and water. Since the low number of oocyst can cause infection and there is no effective disinfectant against cryptosporidium، the investigation dealing with the cryptosporidiosis is of growing interest among many researchers. Therefore، they try to improve the existing isolation methods of C. parvum oocysts even in environmental samples with small number of oocysts، to obtain much purified oocysts for immunological and molecular studies. Different methods have gained some success on the isolation of cryptosporidium، but they didn’t result in obtaining completely pure oocysts. The aim of the present study was to try to develop an isolating system for bacteria free oocysts. For this aim، four flotation methods have been used to isolate the C. parvum oocysts from the feces، including NaCl floatation، sucrose floatation، ficoll gradient and 55% sucrose floatation. A floatation method based on 55% sucrose was evaluated as the best method for the primary isolation of Cryptosporidium oocytes. The nitrocellulose filter (with 3µm pore size) was used to remove bacteria and other contaminants. Our results suggest that the oocysts isolated using filtration were free of bacteria and the amount of pure oocysts was 30%. Although the amount of isolated oocysts was limited، the isolated pure oocysts can be used for proteomics studies.

Sodium hypochlorite has been used for disinfecting of Cryptosporidium in some contaminated environments by this parasite and also in laboratory works it has been used for the purification of the parasite from bacteria and as a treatment for facilitating of releasing the sporozoites of Cryptosporidium (excystation). The excystation is a critical stage of life cycle of the parasite. The purpose of this study was to determine the efficacy of sodium hypochlorite on the laboratory excystation of sporozoites of Cryptosporidium baileyi. C. baileyi oocysts have been isolated and identified from the bursa of fabricus of naturally infected 30- day- old broiler chickens in Shiraz area. The oocysts were propagated in sensitive 2-day-old chicks and purified by modified sheater’s sugar flotation method. Oocysts were exposed to various concentrations of bleach and incubated at various temperatures for 15 min prior to being washed by centrifuging. Then the oocysts were exposed to the appropriate excystation fluid and releasing the sporozoites were observed by light microscopy. Complete excystation inhibition was seen by 2.5% and 5% Sodium hypochlorite at 37 º C for 15 min. Treatment of oocysts with 1.25% Sodium hypochlorite at 4 º C had no effect on laboratory excystation. In other cases there were some degree of excystation inhibition. The results indicate that 25% commercial bleach or 1.25% Sodium hypochlorite at 4 º C for 10-15 min may be suitable for purification and sterilization of oocysts and also this treatment facilitates and enhances in vitro sporozoite releasing from the oocysts.

For the purpose of identifying the most probable type of yeast which manifests the milk claws,15 industrials farms, which held holstein cattle for milk production,were selected randomly.samples were taken from the internal surface of the liners by sterile swabs and then the samples were taken to the mycology laboratory.the samples were cultured in sabourauds dextrose agar and kept in room temperature.the final and definite recognition was done by the yeasts recognition kit(rapid yeast plus system).the type of yeasts which detected were include:C.albicansl C.krusei C.rugosal Cryptococcus.neoformanse,Cryptococcus.humiculus,Crytococcus.albicus,Rodotrola.rubra,Geotrichum.candidum,Trichosporon.beigelly,Sporodiobolus.salmonicolor.in this study,relationship between number of milk claws washing per day and type of disinfected solution with detection of saprophyte yeasts were also considered.

Cryptosporidium as an intracellular parasite causes severe diarrhea in calves. Several cases of cryptosporidiosis have been reported in different Iranian regions. The aim of this study was to follow cryptosporidiosis occurrence in cattle husbandries of Semnan city in Iran. Fecal samples were collected from 200 cows and calves, stained by modified Ziehl-Neelsen method and the cryptosporidium oocysts, size were determined. While the collected oocysts (n=40) showed a morphology similar to cryptosporidium parvum they were smaller than this parasite. In this respect, their mean length, width and length to width ratio were 3.44±0.06 µm, 3.55±0.06 µm and 1.03, respectively. By considering these characteristics and the small size of Cryptosporidium ryanae (as a key characteristic for this species) infection with this species has been suggested. However, further molecular studies would be necessary. The mean prevalence of cryptosporidiosis was 17.5%. However, in diarrheal calves, numbers of positive samples were significantly more than the other cattle. In non diarrheal cases, the infection rate was remarkably higher in cattle when compared with heifers and calves. There was not any relation between number of positive cases and type of husbandry, source of water, base of stable and sex of cattle. However, there was positive correlation between number of infected cattle and quality of basement sanitation, the way of using detergents and number of cattle in husbandry. It can be concluded that cryptosporidium ryanae may affect cattle of husbandries in some Iranian regions as Semnan. Hence, improvement of management and good sanitation of husbandry should be considered as control measures.

Materials for this study were consisted of 100 carcasses of broiler chickens aged 14 to 60 which had died from respiratory problems and/or Gumboro disease with diarrhea. These carcasses were submitted from local poultry farms to the department of poultry diseases of the veterinary college of Islamic Azad University، Tabriz Branch for post mortem examination. Intestinal faecal from colac and cecum، trachea and lung samples from the carcasses were examined for the presence of cryptosporidium oocysts after staining using by modified Ziehl – Neelson technique. In this study Cryptosporidium oocysts were found in 5 percent of intestinal samples and in none of the respiratory samples.