BACKGROUND: Staphylococcus aureus is one of the most important human pathogens that cause infection and also food intoxication by secreting various enterotoxins. Conventional culturing methods to detect S. aureus have some limitations such as being time-consuming due to bacterial growth and low precision and sensitivity in detecting viable but non-cultivable cells. OBJECTIVES: The objective of this study was to detect and quantify enterotoxigenic (A-E) S. aureus in cream pastry products applying PCR coupling with propidium monoazide (PMA) to distinguish dead and live cells. METHODS: One hundred samples were randomly collected from pastry shops in Amol, in a period of 2 months. After preparing dilutions, bacterial pellets were separated and treated with PMA before DNA extraction. Real time PCR was conducted in order to quantify S.aureus cells and enterotoxigenic strains using specific primers. RESULTS: Results of conventional method were close to PMA-qPCR data (P>0.05), but data from qPCR that includes live and dead cells shows more bacterial count than two other methods. Sensitivity of the method applied in the present study, detecting low number of S.aureus cells (less than 10/g) seems considerable. CONCLUSIONS: Findings showed that applying PCR coupling with PMA results in more reliable data than conventional culturing method. Regarding this approach being time-effective, considerably sensitive and specific, it is expected that it be used in food quality control labs in monitoring systems in future.

BACKGROUND: Diarrhea syndrome is associated with irrecoverable damages in the husbandry industry worldwide due to losses resulted from fatality, weight loss, growing weak calves and treatment costs. Hence, investigation of diarrhea causes in different areas is important to attempt management strategies to prevent and control it. OBJECTIVES: Present study was carried to investigate prevalence of some important entropathogens in diarrheic calves until three months old, in Shahrekord suburb husbandries. METHODS: Fecal samples were taken from 82 female calves in first day of diarrhea and were examined for isolation of salmonella, Escherichia coli, clostridium, cryptosporidium, and coccidia through common microbiological and parasitological methods. RESULTS: In general, prevalence of isolated organisms were: salmonella 36.6%, Escherichia coli 24.4%, clostridium 9.8%, cryptosporidium 9.8%, and coccidian 7.31%, and Escherichia coli K99 were isolated from four calves. The most prevalent pathogens were Escherichia coli and Salmonella. CONCLUSIONS: The calves are unavoidably exposed to infectious causes of diarrhea during their whole lifespan, because they acquire organisms from environment immediately after birth. Therefore, attempts at efficient management methods, hygienic principles and receiving enough colostrum, particularly in cold seasons, may be efficient in the control, prevention and decrease of diarrhea and its subsequent losses.

BACKGROUND: Rotavirus Group A is one of the most important causes of gastroenteritis as it is isolated from 30 to 50% of infant diarrhea from humans and other animals. G genotype of the virus is determined by gene sequence of a surface protein of the virus (VP7), one of the most important factors in inducing immunity against the virus which acts very specific to each genotype. OBJECTIVES: In the present study the presence of common bovine rotavirus genotypes A was examined in human rotavirus population. METHODS: A total of 100 stool samples from children under 2 years of age in Tehran and Varamin were collected and to track the presence of rotavirus A, were evaluated using ELISA method. Positive samples were isolated and cultured on the MA-104 cell line after several passages. The positive samples (49 samples) were determined to be the G type using semi-nested RT-PCR and primers specific for bovine common genotype. RESULTS: From 100 samples, 49 were positive in ELISA. Eight samples in the first semi nested RT-PCR showed the desired rotavirus bands and in the second round, the results were positive for the presence of bovine VP7 in two samples taken from Varamin, in one sample, G6, and in another sample, two genotypes of VP7, G6 and G8 were detected, indicating infection with at least two strains of human rotavirus reassortant. Six of the ELISA selected positive samples that were taken to the cell line MA104, showed effects of cell damage (CPE) after 4-5 consecutive passages, demonstrating proliferation of the rotaviruses of this study and so, their viability was confirmed. CONCLUSIONS: The results of this study indicate reassortment between bovine and human rotaviruses and show that in case of occurrence of bovine and human rotavirus infection and the emergence of new human type, due to reassortment strain differences in protein immunogen it is possible to overcome due to lack of maternal immunity in the human population and low efficiency of current vaccines and, ultimately, epidemic and considerable losses may occur. Hence, more research is warranted.

BACKGROUND: Toxoplasma gondii is an intracellular protozoan parasite that can infect most species of warm-blooded animals, including birds and humans. Because of feeding habits of domestic chickens, prevalence of Toxoplasma infection in free-range chickens is considered as a suitable indicator of environmental distribution of oocysts. OBJECTIVES: The present study was designed to investigate the seroprevalence of Toxoplasma infection in domestic chickens from Khorramabad and compare the results obtained from serological and molecular methods. METHODS: In total, 97 serum samples were randomly obtained from domestic chickens and examined for the presence of anti-Toxoplasmaantibodies using modified agglutination test (MAT). Fifty grams of muscles (mixture of breast and heart) and whole brain from seropositive chickens were separately homogenized and examined by PCR which targets the repeated element (RE) of the parasite. RESULTS: Anti-Toxoplasma antibodies were observed in 21 of 97 (21.64%) sera. T. gondii DNA was detected in 10 out of 21 (47.61%) seropositive chickens (with titres of ≥1:20). The low agreement between serological and molecular results can be explained by several factors such as possibility of cross-reactions in MAT and/or limited sample size in PCR. CONCLUSIONS: These results indicate that domestic chickens may have an important role as a source of infection for cats and individuals living in rural areas.

BACKGROUND: Ticks are one of the most important ectoparasites in animals that cause economic losses in livestock industry. So, removal or reduction of ticks on animals is necessary. Cysteine proteases are among the compounds that play an important role in the physiological action of ticks and are a good candidate for the anti-tick vaccine. Cathepsins is one of the most important cysteine proteases. OBJECTIVES: The aim of this study was cloning and expression of recombinant cathepsin L gene of Rhipicephalus annulatus in order to evaluate its immunogenicity. METHODS: After collection the ticks were cultivated. Then RNA was extracted from ticks, cDNA was synthesized by using specific primer of cathepsin and amplification by RT-PCR. The desired genes were cloned into expressional pQE30 plasmid. Further, a shorter sequence of the cathepsin gene (654 bp) was prepared as a synthetic plasmid. The expression of the protein produced by both recombinant plasmids in the E.coliBL21 prokaryotic expression system is carried out and the immunity of the recombinant proteins was evaluated by Dot Blot and Western Blot using serum of challenged rabbits with recombinant protein and calves infected with ticks were examined and compared. RESULTS: The results of this study indicate that the protein derived from recombinant plasmid No. 2 had higher expression and purity due to its solubility. Also, the challenge of rabbit serum with these proteins was able to identify both recombinant proteins. But the serum of challenged calves with ticks did not show a satisfactory response with recombinant proteins. CONCLUSIONS: Although the sera reaction of calves infested with ticks was lower than the challenged rabbits sera with cathepsin L, this result was expected, because L cathepsin protein is considered as a concealed antigen.  Overall, the recombinant cathepsin L could be an appropriate candidate for immunizing calves against Rhipicephalus annulatus, although it seems further investigations are necessary.

BACKGROUND: The protozoancryptosporidiumisan important intestinal parasitic infection in domestic ruminants that has the potential for transmission between humans and livestock throughout the world and Iran. OBJECTIVES: The present study was undertaken to determine cryptosporidiuminfection in different age groupsof cattle and water buffaloesin farms of Mahabad suburb, Iran. METHODS: 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. RESULTS: 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%. CONCLUSIONS: 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.

BACKGROUND: This study was conducted to characterize two fowlpox viruses isolated in Iran and study their phylogenic relationship. OBJECTIVES: The aim of this study was to determine the identity of two pox viruses recovered from a tissue sample with typical lesions of fowl pox and red mites from a laying farm. Fowl pox in poultry industry causes significant economic losses associated with decreased egg production, reduced growth, blindness and increased mortality. The pox virus, by direct or indirect contact, may also be transmitted through vectors such as mites and fleas. Dermanyssus gallinae also known as the poultry red mite is the most important blood feeder ectoparasite affecting poultry, in particular, laying hens. In addition to its significant economic losses, it is considered as a potential vector for a number of important avian pathogens. METHODS: Both isolates were inoculated to chorioallantoic membrane (CAM) of embryonated chicken eggs, detected by specific PCR for pox virus 4b gene and characterized by sequencing and phylogentic analysis. RESULTS: Both isolates developed pock lesions in CAM of embryonated eggs. A 578 bp fragment of the poxvirus 4b gene was amplified in both isolates by PCR. The sequence analyses revealed that the two isolates were 100% identical and placed in the same branch. The nucleotide sequence of these two isolates showed a similarity of 73 to 100% to the other selected avian pox sequences available in the GenBank. CONCLUSIONS: These results confirmed that Dermanyssus gallinae are considered to be an important vector for the spread of fowl pox virus in the flocks. Therefore, controlling the red mites in poultry farms will not only inhibit problems such as blood feeding, decreased production and reduced growth rate, it can reduce the transmission of diseases and pathogenic agents in the farms.

BACKGROUND: Nowadays, researchers are converted silver to nanometer dimensions and using nanotechnology to achieve suitable performance and preserve the poultry health and they are used silver nanoparticles are used for poultry nutrition as a nutritional supplement. On the other hand, at the molecular level no complete reports in poultry breeding have been provided. OBJECTIVES: This study was conducted to evaluate cytochrome P450 gene expression in broiler chickens fed with silver nanoparticles. METHODS: This experiment a completely randomized design with 450 single-day Cobb 500 broiler chicks was divided into five treatments and six replications (15 birds in each replicate). Chickens were fed with (1) control (basal diet), (2) basal diet containing 1% zeolite, (3) basal diet containing 1% of zeolite-coated with 0.5% silver nanoparticles, (4) Basal diet containing with 0.15% organic acids and (5) Basal diet containing 1% of zeolite-coated with 0.5% of silver nanoparticles and 0.15% organic acids in with or without heat stress condition. RESULTS: Results demonstrated the level of expression of cytochrome P450 in broilers fed zeolite (Z) in the 21st day of experiment, silver nanoparticles coated with zeolite in combination with organic acid (NSOA) in 42nd day without heat stress condition and silver nanoparticles coated with zeolite (NS) in day 42 with heat stress condition in intestine and liver had significant increase in expression in comparison with control (C) treatment (P<0.05). CONCLUSIONS: In conclusion, result showed that zeolite and silver nanoparticles were identified as inorganic, chemical and exogenous substances in liver and intestine and up-regulated expression of pollution biomarkers genes. Whereas this effect is not identified in organic acid.

BACKGROUND: Leptospirosis is a zoonotic disease with a worldwide spread, which is very important from two aspects, health concerns in human societies and economic losses due to abortion, stillbirth, birth of weak calves,  Milk-drop syndrome and mastitis and death. The prevalence of an infection at the herd or animal level is a key issue that determines whether the infection should be considered important and which measures and policies should be made and applied. OBJECTIVES: The aim of this search is a meta-analysis study of  the prevalence of leptospirosis and serovars of leptospira interrogans in Iran. METHODS: The search was carried out by relevant literature search from 1997 to 2017 and by keywords: Iran, leptospira, cattle, sheep, goats, buffaloes, camel, and their combination in data banks of Magiran, SID, Iranmedex, PubMed and Google scholar. In this study, 39 articles were finally accepted. For statistical analysis, prevalence rates were entered in the Comprehensive Meta Analysis (CMA) software. RESULTS: The prevalence of leptospirosis in apparently healthy ruminants was 21.5% (95% CI: 17.8-25.8) and Grippotyphosa, Pomona and Canicola were the most prevalent. CONCLUSIONS: According to the high prevalence of pomona in our results, using this serovar in produced vaccines inside the country, applying preventive methods to control infection in herd dogs and gaining a share of the health system budget can have a good effect on for leptospira control program.

BACKGROUND: Health and welfare of dogs can be adversely affected by ectoparasite infestations and these infestations pose severe risks to human health due to close contact between dog and human. OBJECTIVES: This study was carried out to detemine the frequency of ectoparasite infestation in referred dogs to veterinary hospital of Ferdowsi University of Mashhad, Mashhad, Iran. METHODS: From April 2017 to April 2018, a total of 460 dogs were examined for ectoparasites. Age, gender, season, breed, keeping place, hair length, hair colour, pruritus, alopecia and distribution of parasites on different parts of the body of each examined dog were recorded in a questionnaire. RESULTS: Out of 460 dogs examined, 99 (21.52%) were found to be infested with ectoparasites. Forty-eight  (10.43%) dogs were infested with Ctenocephalides canis and Pulex irritans. Rhipicephalus turanicus, Sarcoptes scabiei, Hippobosca longipennis and Rhipicephalus sanguineus were found on 14 (3.04%), 10 (2.17%), 10 (2.17%) and 9 (1.95%) dogs, respectively. Infestation with Wohlfahrtia magnifica, Demodex canis, Otodectes cynotis, Haemaphysalis erinacei and Linognathus setosus were observed in 9 (1.95%), 3 (0.65%), 2 (0.43%), 1 (0.21%) and 1 (0.21%) examined dogs, respectively. There was a statistically significant association between ectoparasite infestation and sex, keeping place and pruritus (p < /em><0.05). No statistical relationship was found between ectoparasite infestation and age, hair colour, hair length, season and alopecia (p < /em>>0.05). CONCLUSIONS: This is the first study conducted on dog ectoparasite infestation in Mashhad district, Northeast Iran. Fleas were the most common ectoparasites and although ectoparasite infestation rate was relatively low, high species diversity was observed. Some of these ectoparasites have zoonotic importance.