ARCHIVES OF RAZI INSTITUTE
Year:2010 | Volume:65 | Issue:2|Papers Count:8

H9N2 avian influenza A viruses are endemic in poultry of many Eurasian countries and have caused repeated human infections in Asia since 1998. It has been also reported that H9N2 can cause high mortality in commercial broiler farms in Iran previously. However there was no report of H9N2 outbreak in any other species. In order to evaluate the pathogenicity of H9N2 virus in Japanese quail, 145 Japanese quail were randomly divided into 5 separate groups (116 quails in the treatment and 29 quails in the control groups). The experimental groups infected via oral rout, eye drop, intramuscular injection and spray method at the age of 32 days with 106.5 EID50/bird. The virus A/chicken/Iran/ZMT-101/98(H9N2) was kindly provided obtained from Razi vaccine& serum institute with EID50=108. The blood samples were experimented the day before use to show freedom from antibodies to influenza A and more specifically, the H9 subtype. The clinical signs and antibody titer of the infected chicks were also monitored. Five birds of each group were bled at 10 and 20 days post infection (DPI), and 20 birds of each group at 30 DPI were bled. The immune response to infection was measured by Haemmaglutination Inhibition (HI) test using the H9N2 virus as antigen. Feed & water consumption were recorded on daily bases before and after inoculation. Body weight of each group was also recorded on weekly bases before and after inoculation. During the current study clinical signs such as sneezing, gasping, depression observed in challenged groups followed by decreasing in laying (1-17%). High HI antibody titers of AIV subtype H9 was seen in 10 DPI. The quails exhibited no decrease in food and water consumption and all quails were growing well and did not show any abnormality.

Since, the most susceptible laboratory animal to Foot–and–Mouth disease virus (FMDV) is guinea pig, and then one milliliter of FMDV type (O) concentrations of 106-106.5 TCID50was inoculated intradermally (ID) to 10 plantar surface of guinea pig (right side). Guinea pig adapted virus has been prepared after generalization phase, and then one milliliter of virus was inoculated intradermally to 30 guinea pigs in 5 groups (each consist of six). Samples from different organs including, heart, lung, liver, spleen, pancreas, tongue and plantar epithelium, retropharyngeal and inguinal lymph nodes were collected on days 2, 4, 14, 30, 60 post inoculation (PI) and kept in transport media and sent to FMD department of Ref lab. According to the results of this study, plantar epithelium and tongue as well as lung have been detected to be the original sites for virus survival. In addition, the highest rate of the presence of virus can be seen on 4 days and 14 days PI. By the way there was no sign of presence of the virus in any organs on days 30 and 60 PI.

Mycoplasma synoviae (MS) is an important avian pathogen that can cause both respiratory disease and joint inflammation synovitis in poultry, inducing economic losses to the Iranian chicken industry especially breeder farms. The aim of this study was to use the MS specific PCR and culture methods in order to detect of M. synoviae from breeder farms where located in Tehran province. A total of 475 samples including choanal cleft, trachea, ovary and /or joint cavities from 23 broiler breeder farms of Tehran area were collected. Samples were cultured in PPLO broth media supplemented for MS isolation. The bacteria DNAs were extracted by phenol/chloroform method. Specific published primers amplify a 207 bp region of the 16S rRNA gene of MS were used for PCR method. Out of 475 samples, 146 cultures were shown positive and typical Mycoplasma colonies, 85 samples were also identified MS based on agglutination test with specific MS antiserum and the PCR method. A total of 122 samples, a band with 207 bp was shown as MS specific PCR product in electrophoresis. In addition to these 85 samples that were positives in both culture and PCR, 37 samples that had not grown in Mycoplasma media were positive in MS specific PCR. A total of 292 samples were negatives in both culture and PCR methods. 122 positive samples out of 475 samples (25.7%) were belonged to 7 breeder farms (30.4%). On conclusions, the MS infection of broiler breeder farms of Tehran area was confirmed truly. From the results, as the PCR method reduces the time consuming, an effectiveness and efficient for detection of M. synoviae infection of chicken breeder. It is then suggested that the PCR method could be an alternative method for culturing.

Hemiscorpius lepturus is medically important scorpion species present in the south and southwest part of Iran, causing morbidity and mortality in children and adults. Unlike other scorpions studied so far, the venom of H. lepturus is highly cytotoxic, that can be a reason for its complexity in clinical manifestations in patients stung by this scorpion. Scarce studies showed the mechanism involved in envenomation by H. lepturus. In the present study, H. lepturus venom in three doses of 50, 500 and 1500 mg/kg was subcutaneously injected into three separate groups of rabbits. Electrocardiograms of all the rabbits were recorded during the experiment. Blood collection was carried out before, one and three hours after venom injection. Serum was used for determination of alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), urea, creatinine, BUN (Blood Urea Nitrogen), creatine phosphokinase (CPK) and creatine kinase isoenzyme MB (CK-MB). In group 1 rabbits although some change were observed in serum biochemical parameters following venom injection but statistically the changes were not significant. In group 2 rabbits significant (P<0.05) increase in LDH, BUN, urea and creatinine was observed 3 hrs after venom (500 mg/kg) injection. In group 3, the venom injection caused highly significant (P<0.01) elevated level of BUN, creatinine, CPK and CK-MB and significant (P<0.05) elevated level of rest of the biochemical parameters. On the other hand, in this group, electrocardiogram abnormalities such as ST elevation and sinus bradycardia in limb lead II were indicator of a mild cardiac injury. In conclusion, it seems that the venom of H. lepturus has the cytotoxic components that severely affecting the organs kidney and liver directly and its mechanism of action is quite different from scorpions in buthidea family.

There is considerable confusion concerning the structure and synonymity of macroscopic sarcocysts in goats. In the present work, ultra structural and molecular study on fat and thin macrocysts of Sarcocystis isolated from naturally infected goats were investigated. Two forms of macro cystic sarcocysts were collected from fresh oesophagus, diaphragm, skeletal muscles and heart of slaughtered goats in abattoirs of Tehran and Ghazvin provinces of Iran. Then ultrastructural and molecular studies were carried out contemporaneous using PCR technique and transmission electron microscope respectively. Based on morphological examinations both cysts differ in shape with naked eye but they had the same wall structure with electron microscopy study. The 18S rRNA amplification by PCR showed a 637-bp band for both forms. The results of sequencing of PCR product of the cysts indicated these two kinds of cysts were identical to each other and also to Sarcocystis moulei. The present result, suggests that fat and thin cysts are the same and identical species.

This study was conducted to evaluate and compare the levels of aflatoxin M1 in raw and pasteurized milk samples during different seasons by Enzyme- Linked Immuno Sorbent Assay in Sanandaj, Iran. In 257 (94.49%) out of 272 milk samples the presence of aflatoxin M1 was detected in concentrations ranging between 0.007 and 115.930 ng/l. AFM1 level in 12 (4.4%) of positive samples were higher than the maximum tolerance limit (50 ng/l) accepted by Iran and European Union countries. Statistical evaluations showed that the differences between raw and pasteurized samples were not significant (p<0.05). There was no significant difference between spring and summer but the differences between other seasons were statistically significant. Winter samples with 22.35 ng/l and summer samples with 5.14 ng/l had the highest and lowest concentration, respectively (p<0.05). Since contamination of milk with aflatoxin is a potential risk for human health, milk and milk products should be controlled periodically for Aflatoxin contamination.

An unusual occurrence of actinobacillosis was diagnosed in 4 heifers aged 8-15 months and 2 cattle in a dairy herd with 190 Iranian Holstein breed. Anorexia, dysphagia, drooling of normal or foodtinged saliva and presence of warts-like lesions on the dorsal surface of tongue shaft were observed in a 15-month-old heifer without showing protrusion of tongue or presenting woody tongue and no involvement of either sulcus lingualis or tongue base. In addition to tongue, soft tissues of oral cavity and pharyngeal region including lymph nodes, salivary glands and tonsils were contained multiple whitish nodules. Histopathologically, typical pyogranulomas of actinobacillosis contained radiating eosinophilic clubs surrounded by many neutrophils were diagnosed. Actinobacillus lignieresii was isolated from the lesions in pure culture. Clinical examination of other animals revealed the presence of different degrees of granulomatous abscesses in soft tissues including skin around mandibles in at least 3 heifers aged 8-11 months and 2 cattle. Due to 4 recent droughty years feeding the heifers, dry cows and low milk producing cattle by cheap oat and wheat straw mixed with plant awns could be the cause of this event.

This investigation was carried out to determine the prevalence of Eimeria infections and the diversity of Eimeria species in camels of Tabriz region. The prevalence of Eimeria spp. infection and the intensity of faecal oocysts were determined in 164 camels using floatation and sporulation techniques. Faeces of 34 camels (20.73%) were infected with four Eimeria species including E. bactriani (52.42%), E. cameli (19.31%), E. pellerdyi (15.68%) and E. dromedarii (12.59%). Of infected animals, mixed infection was at most with four Eimeria species in 10.54% of camels. There was a significant difference between the prevalence of Eimeria infection in camels among different age groups (P<0.05). Infection rate was higher in female camels (54%) with less than one year-olds. There was significant differences in the prevalence between male and female camels in all age groups (P<0.05). It is concluded that Eimeria infection is a problem in camel husbandry in Tabriz region and further studies will reveal more information about economic effects of this parasite which it will be useful for establishing control programs.