نشریه تحقیقات دامپزشکی و فرآورده های بیولوژیک
سال بیست و نهم شماره 4 (پیاپی 113، زمستان 1395)

Ornithobacterium rhinotracheale (ORT) infection is a contagious bacterial disease of avian species, primarily chickens and turkeys which associated with respiratory distress, mortality, and increased slaughter condemnation rates, and high economic losses in the poultry industry throughout the world annually. Signs seen in natural and experimental infections, simultaneous infections with other respiratory pathogens and public health and economic importance of the disease have been analyzed and reviewed in this article. Respiratory signs such as pneumonia, nervous signs, reduced growth, Egg drop and ascites have been observed in commercial chickens of Iran. Observation of purulent cast into the trachea and bronchi and heavy mortalities are common signs of natural and or experimental ORT and influenza virus H9N2 co-infection in Iran. This sign or any mortality was not seen in the case of influenza H9N2 virus experimental infection alone. ORT infection has been reported with high prevalence in various breeds of commercial chicken flocks and also in turkeys. Pathogenicity of ORT strains are not the same and so it is possible to emerge strains with high pathogenicity in poultry industry of Iran. Only a few works have described some of the virulence factors of this bacterium such as non-siderophores iron acquisition mechanisms, neurominidase enzymatic activity, and a hemolysin-like protein. To deal with the disease, some ways including vaccination by autogenous vaccine, drug treatment based on antibiogram and stresses and other pathogens management are effective. Lowering the slaughter age in broilers is another way to deal with the heavy losses caused by ORT infections.

Ornithobacterium rhinotracheale (ORT) is one of the causes of poultry respiratory diseases. In this study in vitro drug sensitivity of 47 ORT isolates using standard disk diffusion were examined with 35 different antibiotics. The isolates originating from commercial chicken flocks submitted in 2000, 2001 and 2007 to Razi institute. None of the isolates was resistant to tiamulin , and less than 50% were resistant against ampicillin , amoxycillin , imipenem , doxycyclin, tylosin ,cefalexin, penicillin, ciprofloxacin, norfloxacin, ticarcillin, chloramphenicol, danofloxacin, florphenicol, ceftiofur, furazolidone and clindamaycin. All the isolates were completely resistant to colistin, erythromycin, gentamicin, co-trimoxazole, sultrim, lincomycin, nafcillin and neomycin. There were antibiotic resistance increase in 2007 isolates compared with 2000 and 2001 in several antibiotics including streptomycin, tetracycline, oxytetracycline, chlortetracycline, ticarcillin, ceftiofur, furazolidone, penicillin, danofloxacin, cefalexin, and linco-spectin. In others no change or even resistance decrease were seen. Of course because of different geographic area and different breeds of birds this comparison cannot be generalized. Because of acquired antibiotic resistance, and various results of antibiotic therapy, it must be stressed to ORT antibiogram test more than before.

Colibacillosisis one of the common illness in the Broiler chicken farms that increase resistance and overuse of drugs in recent years has brought a lot of losses. The aim of the current study was the detection of bla TEM, bla CTX-M and bla SHV in Escherichia coli isolated from poultry by multiplex-PCR and their antibiotic susceptibility profile. A total of 60 isolates of E. coli were collected from the poultry. The antibiotic susceptibility test was determined using the disk diffusion method agreeing with CLSI guideline. Cellular DNA was extracted by CinnaPure-DNA (Cell culture, Tissues, Gram negative Bacteria and CSF) and MPCR was performed for the identification of the CTX-M, SHV and TEM genes.
The antibiotic susceptibility test results showed that, the lowest and highest resistance rate were related to imipenem (0%) and aztronam (77%) , respectively. 41(68.3%) , 28(46.6%) and 0(0.0%) strains were positive for CTX-M, TEM and SHV, respectively. 16(26%) isolates carry out both TEM and CTX-M. Disk diffusion method for laboratory diagnosis of ESBLs is highly functional and cost-effective method that can be given to the importance of ESBLs-producing organisms to test routine is added. In addition, PCR assay for genotyping can be used.

Ornitobacterium rhinotracheale (ORT) is a gram-negative bacterium which causes respiratory disease and reduced flock performance in commercial poultry farms. The aim of the present study was molecular detection and determination of antibiotic susceptibility of ORT in broiler flocks of Golestan province. In this study, 513 samples were taken from trachea, lung and infraorbital sinuses of 50 broiler flocks from 9 poultry abattoirs of Golestan province. Out of 29 flocks(58%) were detected against to Ornitobacterium rhinotracheale infection with using specific primers of ORT in PCR method was amplified A 784 bp fragment of the 16SrRNA gene. Antimicrobial susceptibility test using standard disk diffusion technique was performed with 16 antibiotics. All isolates were susceptible (100%) to: Florfenicol, Tiamulin, Tylosin, Penicillin, Amoxicillin, Ampicillin. Also100% of the isolates were resistant to: Erythromycine, Streptomycin, Gentamycin, Colistin, Neomycin, Sulfamethoxazole Trimetoprim, Bacitracin. The results showed that prevalence rate of ORT infection was high in Golestan province.

The objectives of this study were to compare fertility between heatsynch and estradoublesynch protocols in fresh Holstein dairy cows. Holstein cows with normal ovary and uterus (n= 191, yielding more than 30 kg of milk/d and parity 3.2±1.1) were randomly assigned into two experimental groups, including 1- heatsynch (n=96) , GnRH-7d-PGF2α-24h-EB-48H-TAI or 2) estradoublesynch (n=86), PGF2α-2d-GnRH-7d-PGF2α-24h-EB-48h- TAI. Results showed that estradoublesynch increased the percentage of cows diagnosed pregnant cows at 32 and 60 d after AI (P

In order to compare the existing traditional conditions and the use of slow release bolus containing zinc, selenium and cobalt on performance of pregnant ewes and their lambs, six weeks prior to lambing, 105 ewes were divided into three groups (35 heads each) including: 1) control group; 2) selenium vitamin E injected group; 3) slow-release bolus given group. Data obtained from all the 35 ewes in each group were used to determine the performance of lambs, but to determine the blood and milk parameters 6 of ewes and their lambs from each group were used. Ewes were blood sampled at 10 days prepartum and 45 and 90 days postpartum, and samples of their milk were collected on day 45 also blood samples of lambs were collected at 10, 45 and 90 days old. Body weight on birth and weaning of lambs and average daily gain of lambs were highest in bloused animals (P

Opportunist fungal pathogens (Ascosphaera apis, Aspergillus flavus, Aspergillus fumigatus) cause considerable economic and health losses in honey bees. This article deals with the frequency of these agents in the bee hive in Mazandaran province. For this purpose, five regions (Noshahr, Nour, Amol,sari and Behshahr) were chosen in 1380. Samplings were conducted in the spring, summer and autumn.10 apiaries of each region and from each of which 4 hives were randomly selected In each season. In this study, a total of 468 hives were sampled during three seasons. In the laboratory, microbial cultures Operation were performed on samples. The results showed that 36.5% of samples were contaminated with pathogenic fungi (Ascosphaera apis, Aspergillus flavus, Aspergillus fumigatus). According to the type of sample (bees, larvae, pollen and honey), contamination rate are 37.4 %, 33.3%, 37.1 % and 36.7 %, respectively which is not statistically significant. Also according to the type of pathogenic fungi, contamination rate with Ascosphaera apis, 0.43% and (Aspergillus flavus Aspergillus fumigatus) , 36.07 % has been determined. The difference is statistically significant. Therefore, in this study, Ascosphaera apis infection is very low, whereas Aspergillus flavus, Aspergillus fumigatus infection is abundant.

The aim of this study was to determine the effects of dietary lactoferrin (LF) on digestive enzymes activity, body composition and intestine bacterial flora of sobaity (Sparidentex hasta) with an average weight of 7.64 ± 0.3 g. This study was carried out in a completely randomized design with three treatments and replications in fiberglass tanks with 300 liters volume. Fish were fed with feed containing 0, 400 and 800 mg lactoferrin per kg feed for 42 days. At the end of the experiment, body composition and intestine samples were collected. The obtained results indicated that dietary lactoferrin did not change sobaity digestive enzymes activity, including protease, amylse and lipase (P > 0.05). In this study, weak, positive and no significant correlation were observed between dietary lactoferrin and protease activity, amylase activity, and lipase activity (P > 0.05). The results indicated that different levels of lactoferrin did not affect body composition including protein, ash and moisture and intestine bacterial flora (P > 0.05) but fat content in fish fed on 400 mg lactoferrin per kg feed was significantly higher that control group (P

The present study investigated the effects of Myrtus communis and Ferula assafoetida extracts on percentage of hatching and survival rate in the early growth stages of rainbow trout (Oncorhynchus mykiss) larvae compared with malachite green (MG). This study was carried out in Dalkhan propagation and cultivation farm, in Sepidan, Shiraz. To assess the percentage of hatching and survival rate in the early growth stage, Myrtus communis was used at 400 mg/L and Ferula assafoetida at 40 mg/L for 30 minutes per day and MG as the positive control at 2 mg/L for 20 minutes per day. Normal control without any treatment was also included. Each treatment trial was provided in three replicates. The obtained results showed that the mortality level in normal control was significantly higher than other groups in the hatching stage (p0.05). In addition, the mortality rate of the produced larvae was significantly higher in both Ferula assafoetida group and normal control groups than other two groups (p

In this study 30 fish were caught from 4 species of river fish Shapour River including Chalcalburnus sellal, Cyprinion macrostomum, Capoeta barroisi persica and Garra ruffa in 2014 and after transferring to the Laboratory of Parasitology, Faculty of Veterinary Medicine, Islamic Azad University of Kazerun Branch were examined in terms of internal and external parasites. A total of 12 species were isolated and identified, including 5 monogenian speices (Dactylogyrus carassobarbi, Dactylogyrus holciki, Dactylogyrus alatus , Dactylogyrus pulcher, Dactylogyrus sp. and Gyrodactylus sp.),1 digenea (Allocreadium sp.), 2 nematod (Rhabdochona sp. and Cucullanus sp.) ,1 arthropoda (Lamprolegna sp.), 1 protozoa (Ichthyophthrius multifillis) and 1 myxozoa (Myxobolus sp.). The results showed that the highest percentage of parasitic infestation was Dactylogyrus and the lowest was Lamprolegna and Cucullanus. Also Chalcalburnus sellal and Capoeta barroisi persica allocated the highest and the lowest percentage of parasitic infection, respectively. Based on the results of this study D. alatus were reported for the first time in Iran.

This experiment was conducted to evaluate the effect of Padina astraulis extract on the growth performances of Mugil cephalus in terms of final weight (FW) and daily growth ratio (DGR), feed indices (feed conversion rate) (FCR), voluntary feed intake (VFI), protein efficiency ratio (PER) and lipid efficiency ratio (LER) and body chemical (protein, fat, moisture and ash) and fatty acid composition of Mugil cephalus for 62 days. The experiment was conducted in a completely randomized design with 360 of grey mullet larvae (with average weight of 0.82±0.02g) in 4 treatments and 3 replicates (n=30 in each replicate) and included: control group without using algae extract, an another groups (treatment 2, 3 and 4) the amounts of this extract were 5,10 and 15 g/kg food. The results showed that at the end of experiment, the highest FW (4.22±0.11g), DGI (1.77±0.51%), the lowest FCR (0.95±0.05), the highest VFI (2.81±0.12 %), the highest PER (2.91±0.78), the highest LER (3.66±0.54), the highest crude protein (23.51±0.98%), the highest crude lipid (18.95±0.08%) and the highest poly unsaturated fatty acid (PUFA) including C18:2n-6 (6.51±0.04%), C18:3n-3 (4.81±0.09%) and C20:5n-3 (EPA) (5.21±0.10%) were observed in the diet containing 15 g /kg algae extract in all of these parameters, treatment 4 showed a significant difference compared with control treatment (P

Electric fishing is one of the research methods used for sampling of aquatic species in freshwater and riverine habitats. Also in the marine environment using electric fields to reduce by-catch species and increase targeted fishing activities specially is a common useful method on particular for benthoses species. Electric current density and environmental factors such as water salinity can have different effects on fish species. Therefore, the study of behavioral changes and possible physical effects of electrical currents on fish species are important in terms of biological aspects and changes in population distribution for target prey species. The present study aimed to investigate changes in behavior of common carp (Cyprinus carpio) in experimental pond condition using a variable voltage electric field in different water salinity during entanglement of fishing gear. Common carp behavioral reactions in response to the strength and conductivity of the electric field in the water with different salinity and temperature such as distance from the source of electric current, fear reactions, convulsions and ultimately death of the fish when they were in the test environment were measured. In this study electric field treatments include a range of voltages 240, 225, 210, 195, 180, 165, 150,135, 120, 105 and 90 V in four water salinity levels (0, 2, 4 and 8 g/l) , respectively. The results showed that an increasing of water salinity (0-8) g /l does not have a significant effect on the distance of carp from the electric source. While, the increase in voltage has significant impact on the distance of carp from the electric source. Also in all water salinity treatments the maximum convulsion has been recorded in voltages higher than 150 volts. Mortality was observed at higher voltages above 225 v. Further complementary behavioural studies are needed to investigate potential effects of anthropogenic environmental pollutions including electric fields, produced by commercial fish pond mechanization and fisheries gear developments on fish species behavioural changes in both growing ponds and commercial fisheries activities. Moreover, we suggest that to understand the effects of environmental pollutions at the community levels require more laboratory and field experiments on many fish species at individual levels.

Nowadays due to rapid development and wide applications of nanosized matters, the possibility of their discharge into water bodies and their subsequent toxicity to aquatics are also increased. Total of 135 fingerling rainbow trout with an average weight of 30g were randomly allocated to three treatments in a two-stage completely randomized design experiment. During first 21 days, fish were exposed to three concentrations of the nanoparticles, namely, 0, 25 and 50 ppb. The final post nanoparticle exposure stage was also lasted for 21 days to scrutinize the ability of fish to recover from damage of first stage. Some hematologic, hepatic and biochemical indices of rainbow trout were evaluated at the end of each stage (days 21 and 42). Light microscopic analyses demonstrated cytoplasmic and vacuolated degeneration in hepatocytes enclosed to sinusoids, which were changed to severe hepatic necrosis and inflammatory exudate accumulation. Results from the first stage indicated that GGT was significantly (P

Unicellular yeasts are known as a part of aquatics intestinal flora. Some species are useful and some are known as pathogen for known or unknown diseases. So far any comprehensive study was done to characterize yeast intestine flora of fish in Iran. Due to the importance of isolation and characterization of micro flora of fishes and possibility of introducing this endemic species as Probiotics, in present study, the diversity of the intestinal yeast flora of domestic Rainbow trout fishes of 6 Urmia cities farms was investigated by general and specific diffraction media as SDA, SCC, CHA and CMA following to molecular analyses. Molecular technique of PCR for small fragment of ITS1 was followed by sequencing in order to identifying some complex samples in case of culture methods failure. This study not only succeed to stablishe a protocol for characterization of yeast micro flora of fishes but also could identify some species Candida guilliermondii, Saccharomyces cerevisiae strain LN, Saccharomyces cerevisiae strain YG3-1, Saccharomyces cerevisiae and also strains of Rhodotorula.

Recombinant DNA technology is an in vitro molecular techniques to isolate and manipulate DNA fragments. Using this technique, construction chimeric molecules, called recombinant DNA molecules, then insert the recombinant molecules to living cells, replication and proliferation of the cells was possible. The fusion protein technology is the strategy to achieve rapid, cheap and efficient expression of proteins. Clostridium perfringens type D epsilon gene nucleotide sequence (etxD) and Clostridium septicum alpha gene (csa) were retrieved from GenBank. Then, to produce chimeric fusion protein, epsilon-alpha fusion gene was designed. Secondary and tertiary structures and characteristics of the fusion protein was determined by online software. The results showed that the designed fusion gene construction is suitable to expression of chimeric fusion protein.