BACKGROUNDS: Different susceptibility rates of pathogenic bacteria to antimicrobial agents are considered major factors in the choice of drugs and the success of treatments. Concerns have been raised regarding the emergence of antimicrobial resistance among pathogenic bacteria that may result in unpredictable antimicrobial susceptibilities and therapy failure. OBJECTIVES: The purpose of this investigation was to determine the antimicrobial susceptibility of 1,000 bacterial isolates to five antibacterial agents commonly used in the Iranian poultry industry. METHODS: From July 2008 to June 2009, the antimicrobial susceptibility of 1,000 bacterial isolates to five antibacterial agents was tested. These agents that are commonly used in the Iranian poultry industry include colistin, doxycycline, enrofloxacin, florfenicol, and sulfamethoxazole + trimethoprime. The data were provided by 19 laboratories in eight Iranian provinces. RESULTS: The bacterial species belonged mainly to Escherichia coli and Salmonella spp. Of all tested samples, 55.5% were resistant to colistin, 61.5% to doxycycline, 41.5% to enrofloxacin, 34.5% to florfenicol, and 65.5% to sulfamethoxazole + trimethoprime. CONCLUSIONS: The findings of this survey represent the high frequency of resistance to antimicrobial agents commonly used in the Iranian poultry industry. They also highlight the need for the implementation of a national monitoring program for antimicrobial resistance and for a rational use of antimicrobial drugs.

BACKGROUNDS: Optimization of microbial compositions and load in live food during the process of bioencapsulation is one of the most important concerns in aquaculture, as it can promote the growth and feeding parameters of fish larvae. OBJECTIVES: The aim of this study was to determine the growth and feeding performance of Persian sturgeon larvae fed with bioencapsulated D. magna with Saccharomyces cerevisiae. METHODS: D. magna were bioencapsulated with S. cerevisiae at three concentrations of 5, 5.30 and 5.48 Log CFU ml-1 for 10 hours. P. sturgeon larvae were fed using enriched D. magna at 30 percent of their body weight, six times a day. Controlled treatment was fed on unbioencapsulated D. magna. RESULTS: The results indicated that the S. cerevisiae promoted the growth and feeding parameters in P. sturgeon larvae. The final body weight and specific growth rate (SGR) in experimental treatments had significant difference in comparison with control treatment (p

BACKGROUNDS: Gyrodactylus is a small monogenean ectoparasite that lives on the skin and fins of most of the world's fish species. Gyrodactylus appears to be one of the most prevalent parasites found in ornamental fish, especially in Cyprinids. Goldfish (Carassius auratus) are a popular ornamental fish that are highly contaminated by Gyrodcatylus. OBJECTIVES: The present study is aimed to identify morphological and molecular character-istics of the Gyrodactylus parasite on gold fish. METHODS: The morphological identification of Gyrodactylus specimens was performed using the measurements and drawings of opisthaptoral hard parts of the parasites. The molecular species description was based on a polymerase chain reaction (PCR) of partial sequence of the 5.8S region of ribosomal RNA, and a partial sequence of the internal transcribed spacer 2 (ITS2) of ribosomal RNA. The nucleotide sequences of the PCR products were compared with corresponding sequencing registered in GenBank. RESULTS: Based on the morphometric analysis and sequencing, the Gyrodactylus specimens were described as Gyrodactylus gurleyi. CONCLUSIONS: A combination of molecular techniques with morphological analysis seems to be the best approach for the identification of Gyrodactylus speices.

Encephalomalacia is softening or loss of brain tissue following cerebral infarction; cerebral ischemia infection, craniocerebral trauma or other injuries. Cholangiocarcinomas are malignant neoplasms of biliary epithelium, which usually arise from the intrahepatic ducts. A budgerigar was presented with a history of ataxia, decreased activity, neck weakness and weight loss. Supportive care was attempted, but the bird did not improve and euthanasia was elected. At necropsy, the liver was pale and large. There were two symmetrical pale areas on the cortical surface of cerebrum. Representative specimens from all tissues were fixed in 10% buffered formalin, embedded in paraffin and stained with hematoxylin and eosin (HE). In gray matter of cerebral tissue, there were small clear vacuoles of varied size that formed in the cytoplasm of neuron cell bodies. Proliferation of capillaries was seen. The fluid-filled clear spaces were in the white matter especially in peduncles. There were a few thromboses in the vessels and neuronal necrosis of cerebrum. Neoplastic tissue was limited to the liver. There were numerous epithelial lined ducts with an associated dense fibrous stroma. Cholangiocarcinoma and encephalomalacia were confirmed based on the macroscopic and microscopic evidences. It seems that chronic exposure to a mycotoxin and vitamin E deficiency are probable causes of encephalpmalacia and cholangiocarcinoma in this bird.

BACKGROUND: Gallstones are concretions that form in the biliary system. There are two major types of gallstones (pigment and cholesterol), which seem to form due to distinctly different pathogenic mechanisms. OBJECTIVES: The aim of this study was to determine the prevalence and chemical composition of gallstones in goats. Bacteriologic analysis and pathological findings were reviewed. METHODS: The study was carried out on 411 goats at Juneghan abattoir in Chaharmahal-Bakhtiari province of Iran. RESULTS: Gallstones were found in the gallbladder of 5 goats (1.2%). Biliary calculi were more frequent in adult goats (p

BACKGROUND: Fat replacers are ingredients that can replace fat in many foods, therefore,many consumers have limited their dietry intake of fat and calories due to diet and health concerns. OBJECTIVES: The present study investigated the effect of modified starch on some physico-chemical and sensory properties of low fat Hamburger. METHODS: In this research, modified starch potato, tapioca (Acetylated distarch adipate) and waxy maize (Hydroxypropyl distarch phosphate) at 0.5, 1.5 and 3% levels were used as the fat replacers. The amount of fat was reduced from 20% to 10% in control. Physical (cooking losses), chemical (e.g. moisture, protein, fat, ash) and sensory characteristic were assessed compared with control one. RESULTS: Results showed that moisture content in samples containing starch was decreased and there was a significant difference between samples containing starch and the control (p

Background: The complex process of spermatogenesis is regulated by various factors. Studies on spermatogonial stem cells have provided a very important tool to improve herd genetic and different field. 0.2 to 0.3 percent of total cells of seminiferous tubules consist of spermatogonial stem cells. To investigate and biomanipulate these cells, first the proliferation and viability rate of cells should be increased in vitro. Objectives: In the present study, the in vitro effects of testosterone on spermatogonial cell colony formation were investigated. Methods: Sertoli and spermatogonial cells were isolated from 3-5-month-old calves. The identity of the cells was confirmed through analysis of immuno-cytochemistry. Co-cultured Sertoli and spermatogonial cells were treated with testosterone in different doses of 0.2 µmol L-1, 0.4 µmol L-1 and 0.8 µmol L-1, before colony assay. Results: testosterone did not decrease the proliferation of spermatogonial stem cells. Conclusions: testosterone can be chosen for in vitro colonization of spermatogonial cells with other factors.

BACKGROUND: Caprine pox virus disease play an important role in major constraints to small ruminants production in Iran. OBJECTIVES: This study was conducted in different districts of Iran to determine the prevalence of goats pox virus disease in different age groups, sex and seasons in Black goats of Iran. METHODS: In this study skin lesions of male and female goats were collected randomly from different provinces during (January, 2007 to November, 2010). A total of 318 samples were examined, of which 66 were found positive. RESULTS: The overall prevalence rate was 20.75%. Pox virus disease was observed significantly higher in older (58.33%) female goats (36.79%) and in rainy seasons (26.16%). The estimated economic losses due to condem-nation of skin deficiency were 5.59% which cost US$115.44 per thousand skin of slaughtered goats. The prevalence was significantly different (p|£|0.05) in different age groups and sex of the animals. CONCLUSIONS: The present study indicates that pox virus disease infection in goats is associated with age, sex of animal and seasons of the year. To control the disease in infected provinces, appropriate preventive control strategies have to be designed to reduce the impact of the disease on goat production in Iran.

Background: Poultry products have been recognized as major sources of human gastrointestinal disease caused by Salmonella spp. and several outbreaks have been reported where eggs were the source of human infection. OBJECTIVES: This study was carried out to determine the prevalence of Salmonella spp. in the quail egg interior contents from retail stores of Semnan, Iran and to characterize the isolated Salmonella serovars via serotyping and Multiplex PCR techniques. METHODS: 140 packages of quail eggs (each package containing 12 eggs) were collected from different batches during summer 2010 and tested for the presence of Salmonella through conventional culture and serotyping methods. RESULTS: From these samples, S. enteritidis was detected in the egg contents of one package (0.71 %) out of 140 packages. This isolate was confirmed by Multiplex PCR generated amplification products for a random sequence that is specific for the genus salmonella and spv and sefA genes. CONCLUSIONS: According to our results, S. enteritidis is the most prevalent serotype of quail egg content contaminant in the Semnan area of Iran and the multiplex PCR method could be used as a reliable method of identifying Salmonella serovars.

BACKGROUND: Several regulatory proteins are involved in Salmonella invasion. The key regulator of SPI-1 (Salmonella pathogenicity island 1 ) is hilA, a transcriptional activator encoded on SPI-1 that regulates the expression of the SPI-1 secretion system. OBJECTIVES: Importance of hilA mutation on S. enteritidis colonization and shedding in layer hens was evaluated in a long-term experiment. METHODS: Two groups of layer hens were orally inoculated with 1010 CFU of hilA and parent strains of S. enteritidis, consequently. At days 2, 7, 14, 21 and 35 post-inoculation samples were taken from cloaca and different parts of digestive and reproduction systems of euthanized birds. RESULTS: In the birds infected with parent strain, the higher numbers of colonizing bacteria in the liver, spleen, caecum, small intestine and cloaca-vagina were observed. Fecal shedding in this group was also higher than the hilA group. However, no significant differences were observed for the colonization of bacteria in magnum, isthmus and infundibulum of both groups. Using PCR method, hilA gene was only detected in tissues of parent group hens. CONCLUSIONS: This study has shown that the hilA mutant is able to colonize in internal organs; an implication of this is the possibility that genes other than hilA, or at least other mechanisms, might be involved in the invasion of S. enteritidis to the internal organs of birds.