BACKGROUND: Brucellosis is one of the most dangerous worldwide infectious zoonotic diseases that are common between ruminants and human. Consumption of infected milk and by-products is the major transmission source to human. In Iran, sheep compared to cow, has a higher rate of contamination with brucellosis. Therefore, early detection and precision could be a starting point for any efficient program to control the disease in human and animals. For brucellosis monitoring, milk ring test (MRT) is recommended but the test is not reliable in sheep herds. Perhaps a more realistic outcome could be achieved by changing the antigen used in MRT. OBJECTIVES: Comparison of two Brucella abortus and Brucella melitensis antigens in MRT for detection of Brucella antibodies in milk, as well as monitoring contamination of  ewe’s milk in Dezful region by detection of B. abortus and B. melitensis genes using PCR. METHODS: In this research, 220 milk samples from 16 different herds were collected from Dezful region’s nomadic at Khuzestan province. As the first step, MRT by two antigens, B. abortus and B. melitensis, were conducted on the samples. Next, the samples were subjected to detect Brucella genes using PCR technique. RESULTS: Results showed that 47 (21/3 %) out of 220 cases were positive by MRT test, in terms of both antigens of B. abortus and B. melitensis. In PCR, out of 220 samples, only 9 (4%) samples were positive for specific genes of B. melitensis which were MRT positive as well. CONCLUSIONS: A significant difference between B. abortus and B. melitensis antigens was not observed in MRT. Although the nature and basis of PCR and MRT methods for the diagnosis of brucellosis is different but a significant difference between the results obtained by PCR and MRT showed that MRT even by changing of antigens is still not authentic. Considering that various methods of identification have their limitations, it is recommended that in ewe’s milk samples, in addition to using a serological method as screening, PCR and culture methods should be used for definitive diagnosis.

BACKGROUND: Neospora caninum is one of the most important pathogenic protozoan parasites causing bovine abortion around the world. Objectives: The aim of this study was to detect the presence of Neospora caninum in the brain, cerebellum and medulla oblongata of aborted fetuses in cattle in Arak by means of molecular method. Methods: 38 samples of brain, cerebellum and medulla oblongata from aborted fetuses in dairy cattle of Arak were tested for the presence of Neospora with nested-PCR. Results: Survey findings indicated the presence of DNA in 26.3 % of aborted fetal brains. In the cerebellum and medulla oblongata samples no Neospora caninum  DNA was detected. There was a significant relationship between neosporosis and maternal age (number of calvings), abortion history and the presence of dogs in the herd. Conclusions: The results showed a significant association between the infection and the number of abortions in the examined cows; As a result it seems that neosporosis could be an important factor in epidemic abortions in Arak city’s dairy farms which requires continuous monitoring and implementation of prevention programs in the dairy industry.

BACKGROUND: Neospora caninum is a protozoanintracellular parasite which is considered as one of the main factors forrecurrent abortions of dairy cattle in various countries such as Iran. Thisparasite leads to negative economic impacts such as decline in reproduction,reduced amount of milk, and long calving intervals. OBJECTIVES: Therehave been numerous tests to determine the cause of abortion. PCR test isconsidered as a suitable method to specify Neospora caninum DNA and itcan determine the DNA in tissue samples and body fluids of the aborted fetus.This study aims to use PCR to evaluate parasites in the tissues of abortedfetuses so as to detect the best tissue for determining the parasite. METHODS:In this study, 82 aborted fetuses in the first six months of 2015 were studied.The tissues were selected from brain, liver, lungs, spleen, kidneys and rennetfluids. The NP21plus primer was used to detect the presence of Neosporacaninum in samples. After conducting the PCR Test, samples with 340bp bandin Gel electrophoresis were considered as positive. Statistical data from thesurvey of Neospora caninum’s presence in selected tissues were evaluatedby SAS (version 9.2) software. RESULTS: Contamination with this parasitewas found in 34 brain samples (41.5%) of aborted fetuses. In 2 (2.4%) and 4(4.9%) of the aborted fetuses, parasite DNA was found in lung and liver tissuesalong with brain tissues, respectively. CONCLUSIONS: Due to significantdifference of infection of brain tissues in comparison to other tissues, ourstudy considers brain tissue as the most appropriate sample for detecting Neosporacaninum infection in aborted fetuses in PCR method

BACKGROUNDS: Toxoplasma gondii is an intracellular parasite, which is widely prevalent in sheep throughout the world. Parasite infection can occur pre- or post-natally. Congenital ovine toxoplasmosis occurs following a primary infection in a pregnant ewe and leads to abortion and stillbirth of the fetus causing important economical losses to sheep industry. OBJECTIVES: The present study was conducted to evaluate the presence of T. gondii DNA in brain samples from fetuses of slaughtered ewes in Khorramabad, west of Iran. METHODS: In total, 60 brain samples of ovine fetuses were collected. Examined fetuses were categorized in three age groups (4 months). Fifty grams of each sample was homogenized by mortar and pestle. DNA extraction was performed using a DNA isolation kit (MBST, Iran). A polymerase chain reaction (PCR) which targets the repeated element (RE) of the organism was used for tissue samples. Brain samples were considered T. gondii-positive if the expected band size (529 bp) appeared. RESULTS: T. gondii was detected in 4 out of 60 (6·7%) examined fetuses. No case was recorded in the age group

BACKGROUND: Tilapia is one of the important farmed fish in the world. In the recent years this fish has been grown for evaluating the possibility of farming in climate status of Bafgh region. OBJECTIVES: The aim of this study was identification of some important bacterial pathogens in farmed tilapia. METHODS: In this study thirty fish with 153.4 g (average weight) and 20.12 cm (average length) were randomly collected from ponds. Some bacteriological and biochemical tests such as gram staining, Catalase, H2S production, Indole and motility were used. For definitive identification of isolates, PCR test was done by use of special paired primers. For each bacterium a target gene is detected. RESULTS: From two bacterial groups, gram positive and gram negative, six species were identified. In the gram positive group, Lactococcus graviaea and in the gram negative group, Yersinia ruckeri, Aeromonas hydrophila, Vibrio alginoliticus, V. parahemoliticus and V. vulnificus were identified. CONCLUSIONS: Understanding of different bacterial agents in the fish farm environments is essential for cultivation of tilapia. There are different bacterial agents, each of which can be considered to threaten the living conditions of fish. Respecting the health management leads to increasing  fish immunity and helps  their survival in the cultivation status.