جستجوی مقالات مرتبط با کلیدواژه « cryptosporidium parvum » در نشریات گروه « دامپزشکی »

Cryptosporidiosis is a parasitic disease caused by the cryptosporidium protozoan in vertebrate animals. In livestock, especially ruminants, infants develop diarrhea syndromes. The infection is widespread throughout the world, as well as in Iran, which is reported from various species. Morphological diagnosis of Cryptosporidium species has many limitations and is of no taxonomic value alone, therefore using molecular methods helps remove these limitations to some extent. The current study is aimed at microscopic, molecular, and antigen detection and isolation of Cryptosporidium Parvum parasite. Firstly, there were 300 specimens collected from different parts of Iran. Next, purification of oocysts from feces was carried out according to the method of Casemore et al., through the flotation technique following which staining was done by means of the modified Ziehl-Neelsen method (Henriksen method), and identification through diagnostic keys. ELISA test was also performed on the specimens for which the results were from 1 positive to 4 positive. Results of our study demonstrated that from the 300 cases tested for Cryptosporidium through the molecular method, 48 cases (16%) were positive. These cases were collected during summer, autumn, and winter, however, more than 50% of positive cases were found among specimens collected in autumn. Furthermore, there were 54 positive cases found by means of PCR test, which indicates 6 cases more than that for ELISA results. Finally, results from PCR detection and ELISA, were subjected to Chi-Square analysis, where no significant difference between the collected data was observed (p=.0587).

Cryptosporidium parvum is a coccidian parasite with worldwide distribution.

It is considered one of the most important causes of diarrhea in many vertebrate species and im-munocompromised humans. Due to the lack of effective treatment of cryptosporidiosis, protection strategy against this species can be focused on encouraging the immune system through vaccine development.

For this aim, we prepared oocysts lysate as a whole antigen vaccine candidate (420 μg) and immun-ized 3 pregnant cows 4 times every 2 weeks from 70 days to parturition. As a control group, 3 unimmunized pregnant cows were used. After parturition, each calf was fed with colostrum of his dam and challenged at 12h of age with 1×107C. parvum oocysts.

In contrast to the test group, the calves in the control group developed severe watery diarrhea with excretion of oocysts from 4 days post-infection. The calves in the test group, which received the hyperimmune colostrum, showed no clinical signs and a significant reduction in oocysts excretion.

The whole antigen prepared from oocysts of C. parvum can be considered a suitable candidate for immunizing pregnant cows producing hyperimmune colostrum.

Protozoan parasites are very important in drinking water production systems because their cystic forms are stable in the environment and resistant to conventional disinfection methods. The present study aimed to investigate protozoan parasites in the drinking water of different places in Samarra, Iraq. To this end, 100 samples of tap drinking water were collected from 10 places in Samarra, Iraq (i.e., Al-Sekek, Al-Kadesia, Alzeraa, Al-Shuhdaa, Al-Muthana, Al-Shorta, Al-Mamal, Al-Khedraa, Al-Efraz, and Al-Jubereaa), from the beginning of December to the end of February. After sample collection, water samples were examined to detect oocysts or cysts of protozoan parasites by using Direct wet smear, Lugol’s iodine, and Modified Ziehle Nelseen stain methods. The results indicate that 80% of the samples under investigation were infected with protozoan parasites, and the ratio of diagnostic parasites in the samples under investigation was determined at 36% with Entamoeba histolytica, 23% with Giardia lamblia, and 21% with Cryptosporidium parvum. The findings reveal the presence of protozoan parasites in the drinking water of the area under study and specify the need for a rapid improvement of the monitoring systems for the treatment of drinking water to control diseases caused by these pathogens, as well as to identify the sources of contamination.