BACKGROUND: Yersinia ruckeri is the etiological agent of enteric red mouth (ERM) or yersinioisis disease, one of the important bacterial diseases in the cultured salmonids. OBJECTIVES: The purpose of present study was detection of gyrA gene (quinolone resistance) in the Y. ruckeri bacterium. METHODS: In this study fish were evaluated in average size 8-12 cm from six rainbow trout farms in Chahar Mahal va Bakhtiyari province (Iran). In each farm 10 fish (totally 60) suspected to yersinioisis were randomly selected; sampling was done from lower part of intestine and cultured on Trpticase Soy Agar (TSA). The mediums were transferred to incubator and kept at 22 °C for 48 hours. Pure colonies which are grown on the mediums were tested by catalase, oxidase and gram staining, then those of gram-negative, catalase positive and  oxidase negative were diagnosed, and cultured on Waltman- Shots medium (as specific medium for Y. ruckeri). These mediums were incubated at 22 °C for 48 h. Colonies that were grown were tested by PCR method for Y.ruckeri detection. Then, in the identified strains of Y.ruckeri gyrA gene were detected by PCR test. RESULTS: The results of bacteriological, biochemical and molecular tests showed that three cases out of total isolates were identified as Y. ruckeri. In all isolates of Y. ruckeri, gyrA gene was identified by molecular test. CONCLUSIONS: Identification of quinolone resistance gene in Y. ruckeri isolates can be the reason of low efficacy of these classes of antibiotics in the aquaculture. ِTherefore, the policy of treatment should be changed specially in enteric red mouth disease.

BACKGROUND: Vitamins are considered an essential part in diet of aquatic animals. OBJECTIVES: This study was carried out to assay the effect of different levels of vitamin E on growth performance, carcass compositions and blood parameters of common carp fingerlings (Cyprinus carpio). METHODS: Total number of 96 common carp fingerlings weighing 15.49 ± 3.64 g were randomly distributed into 12 fiberglass tanks in four treatments group including control (without added vitamin), 100, 200 and 400 mg/kg vitamin E in three replicates and kept at a density of 8 fish per tank for 10 weeks. RESULTS: Results showed that the highest weight gain, percentage of body weight increase, mean daily growth, specific growth rate, condition factor and the lowest food conversation ratio were observed in fish fed with 200mg/kg vitamin E but no significant differences were seen compared to other treatments (p>0.05). Fish fed with 200mg/kg vitamin E had the highest (p>0.05) contents of protein and ash compared to control group. There was an increase in values of RBC, Hct and Hb in fish fed with 100, 200 and 400 mg/kg vitamin E in comparison with control group. Significant differences were observed in MCHC in fish fed with 100 mg/kg vitamin E compared to control and fish fed with 400 mg/kg, also treatment 200 mg/kg with treatment 400 mg/kg vitamin E (p<0.05). Fish fed vitamin E in 200 and 100 mg/kg had the highest WBC count. Fish fed with different levels of vitamin E had higher lymphocyte in comparison with control group and fish fed with 100 mg/kg had significant difference with control in lymphocyte (p<0.05). CONCLUSIONS: Vitamin E in level of 200 mg/kg can play an important role to enhance growth performance, nutrition efficiency and improving blood indices and support cell immunity in common carp fingerlings.

BACKGROUND: Heat stress is very important in poultry production. OBJECTIVES: To evaluate the effect of oral elatoninsupplementation and increasing of dark period on biochemical profile of broiler chickens under Heat Stress (HS). ETHODS: A total of 200 day- old broiler (Arian) chicks were randomly allocated in to 4 groups (dark ,melatonin, negative and ositive controls). Melatonin group  received 40 mg melatonin/kg  diet from 30-40 days of age and chickens of dark group were xposed to  a  special lighting schedule from 10-40 days of age. All groups (except negative control) were daily exposed to HS (39± 1 c) for 6 hours per day from 35-40 days of age. At the end of 6 weeks, body weight was measured. At 30, 35, and 40 days, serum uric acid, glucose, total protein, albumin, globulin, activity of AST  and creatinine were measured.  atawas analyzed by ANOVA and Tukey test in SPSS software. RESULTS: In 30 days, there was no significant difference etween groups. In the day 35, only serum uric acid of melatonin group was significantly increased in comparison with egative control. Also, serum uric acid of melatonin group  increased significantly in 40 days in comparison with other roups, as melatonin plays an important role in the antioxidant defense system and uric acid is an important antioxidant inchickens. Serum glucose of positive control compared to other groups significantly increased in 40 days. Other biochemical parameters were not significant. In this study,the mean body weight of dark group was significantly decreased. The  percentage of mortality rate in negative control, dark, melatonin and positive control  treatments was zero, 4 ,5  and 10% respectively. CONCLUSIONS: These results demonstrate that  dark period and oral melatonin supplementation  candecrease HS.

BACKGROUND: Dietary nucleotide has been shown to improve growth indices, nutritional function and higher vertebrates in fish. OBJECTIVES: We investigated the effect of different levels of dietary nucleotide on growth parameters, whole-body composition and fluctuations of cortisol and glucose due to acute stress in Snow trout (Schizothorax zarudnyi). METHODS: One-hundred-twenty Snow trout fingerlings with average weight 7.58±0.05g, were fed with four levels of dietary nucleotides including 0 (control), 0.15, 0.25, and 0.5 percent for 8 weeks. Ten fingerlings were stocked into each 300l tank with triplicate in four treatments and fed three times daily at 3-5% body weight rate. At the end of feeding trial, weight gain, Weight gain rate, feed efficiency, Food efficiency ratio and survival were computed. Also, the numbers of fish that were exposed to acute stress (temperature and pH). RESULTS: The results showed that none of the nucleotide-supplemented diets had any significant effect on growth indices (p>0.05). None of the dietary treatments resulted in any significant changes to dry matter, ash and protein. The only significant difference was observed in the fat (p>0.05). The fish fed 0.25% nucleotide showed higher whole lipid compared to other dietary treatments. Stress test results showed no significant difference at the beginning of the experiment, whereas after, acute stress cortisol levels were significantly higher in trials. The lowest response was observed in trial with 0.50% nucleotide and the highest was in control groups. Glucose levels were not significantly different, neither before nor after acute stress. CONCLUSIONS: The nucleotide composition used in the present study failed to provide significant effects on growth of Snow trout juveniles but could improve response to acute stress.

BACKGROUND: Biofloc technology is considered  a method that degrades organic waste by microorganisms and produces bacterial flocculation. OBJECTIVES: This study was performed to evaluate of the application of biofloc technology in therearing of common carp (Cyprinus carpio) fingerlings in intensive culture. METHODS: The experiment was designed in four treatments (Commercial diet as a control, 75% commercial diet + Biofloc, 50% commercial diet + Biofloc, 25% commercial diet + Biofloc) with carp fingerlings (Initial weight 58 ± .2 g) over a period of one month. Water exchange in Biofloc treatments was 1% during 24 h while water flow through system was used in control. At the end of experiment, all fish were intraperitoneally injected with 12×107 colony forming units (CFU) of Aeromonas hydrophila per fish. RESULTS:The results of the experiment indicated that the highest weight gain was observed in fingerlings fed 75% commercial diet + Biofloc that differed significantly from the group fed 25% commercial diet + Biofloc (p<0.05). There was no significant difference between control and 50% and 75% commercial diet as well (p<0.05). No significant difference was observed in case of condition factor, viscerosomatic index (VSI) and survival in experimental treatments (p>0.05). Also, Biofloc significantly increased ash content in muscle (p<0.05). The highest mortality (64.2 %) was observed in control inchallenge of Aeromonas hydrophila. CONCLUSIONS: The results suggest that the Biofloc technology can increase growth performances of carp fingerlings in intensive system and decrease water exchange via quality improvement.

BACKGROUND: Improvement of hatchability in aging broilerbreeder has economic justification. OBJECTIVES: The main objective ofthis study was to determine the effect of dietary Anethum graveolensessential oil on egg quality, some plasma metabolites and hatchability inbroiler breeder hens. METHODS: A total number of eighty hens and eightcocks from Ross 308 strain of 105 weeks old were divided into four groups withtwo replicates within each (10hens+ 1cock). The diets were supplemented without essential oil (Control) and with 10, 20 and 40 ml essential oil/100kg dietsfor four weeks. RESULTS: There were no significant differences among thegroups in Haugh unit and yolk index. While, there were significant differencesin egg weight, egg shape index, shell thickness, shell ratio, yolk color andshell weight. Plasma triglyceride, high density lipoprotein cholesterol (HDL-C)and egg yolk cholesterol concentration were not influenced by dietary essentialoil of Anethum graveolens. Whereas essential oil increased plasmacholesterol significantly, it also significantly decreased plasma glucose.Hatchability and fertility were positively affected by supplementation ofessential oil in the diet. CONCLUSIONS: Results of this study showedthat supplementing diet with  Anethumgraveolens essential oil improved hatchability of total eggs set of broilerbreeders.

BACKGROUND: The correct usage of  wastes in animal nutrition causes  decrease in environmental pollution. Apple pomace as an energetic matter and source of digestible fibers for ruminants is a proper alternative for forage. OBJECTIVES: The aim of this experiment was to investigate the effect of diets containing dried apple pomace on digestibility, rumination, microbial fermentation and blood glucose and urea of Arabi sheep. METHODS: In the first step, 0, 10, 20 and 30% dried apple pomace replaced with alfalfa were used in the experimental diets. According to the result, gas production and digestibility of diet containing 30% dried apple pomace was higher than the other diets (p<0.05). Therefore, in the second step, 8 Arabi sheep were fed with diet without apple pomace (control) and diet containing 30% apple pomace for 45 days. RESULTS: The result showed that nutrient digestibility (dry matter, organic matter, NDF and ADF) were not significantly affected by the diets (p>0.05), but rumination activity of diet containing apple pomace decreased (p<0.05). Blood metabolites (glucose and urea) showed no significant differences between experimental diets, but blood glucose was higher in control treatment. Rumen ammonia nitrogen concentration was 14.48 and 17.49 mg/dl (p>0.05), and pH was 6.30 and 6.16 for control and apple pomace treatment, respectively (p<0.05). The rumen protozoa numbers increased with apple pomace (p<0.05). Diet containing apple pomace increased gas production potential and digestibility of wheat straw by rumen microorganism and bacteria (p<0.05). CONCLUSIONS: The results of this study suggest that alfalfa replaced with 30% dried apple pomace in Arabi sheep’s diet can improve digestive activity of rumen microbes and nutrient fermentation and digestibility.

BACKGROUND: Mastitis is an important health disorder in dairy herds which affects milk production, animal reproduction and production. OBJECTIVES: The aim of this study was to estimate the cumulative incidence of mastitis in dairy herds in Tehran province.  METHODS: From 679 dairy herds in Tehran province that have more than 50 animals, 32 dairy herds were selected randomly and animals that had calved from March 2007 to March 2008 were followed until the next calving or culling. In total 10506 animals were included in the study. The information on number, parity, occurrence of mastitis was gathered from registry forms. RESULTS: Cumulative incidence of mastitis in this study was calculated 35.8% (95% Confidence interval (34.9-36.8), 3764 animals of 10506). Incidence of mastitis was increased by the increasing parity of animals, and animals in fifth parity have the most incidence. CONCLUSIONS: The results of this study showed the incidence of mastitis in this area is very high and it is necessary to control it.

BACKGROUND: Schistosomiasis is considered as one of the most important infections in ruminants. The flukes are found in the blood vessels of animals. This parasite has been observed in many countries such as: Turkmenistan, Kazakhstan, Iran, Iraq and parts of Europe. OBJECTIVES: Aim of this study was to determine the contamination of Schistosoma turkestanicum in sheep in the central region of Mazandaran province during the year 2012-13. METHODS: Based on the high mortality rate reported by Mazandaran Veterinary Organization in some herds in the cities of the north of Iran During investigation 21.2% mortality was seen in infected herds by necropsy; Schistosoma turkestanicum was diagnosed  as cause of death. Examined infected herds and fecal samples were collected directly from the rectum of sheep.  Samples were examined by flotation method and obtained results were analyzed by statistical tests. RESULTS: During present study which was performed in five central cities of Mazandaran, the highest infection rate was found in Babolsar and the lowest was found in Moghrikola region of Babol. Mortality rate was also evaluated based on gender and it was shown that mortality rates in females were higher than in males (p<0.05). CONCLUSIONS: Ornithobilharziosis, is considered one of the endemic diseases in some parts of Iran and several epidemics have occurred in recent years in Iran. Because this parasite causes  significant economic losses in herds of sheep and goat in Iran, due to its location in the ruminants body and because Mazandaran province is one of the important foci of infection, more attention of the veterinary organization and its institutions is needed for better and greater control of infection.

BACKGROUND: The Mesobuthus eupeus scorpion venoms are known to contain α-toxin peptides, many of which interfere with K+ ion channel function. These toxin peptides have important value in  the pharmacology and physiology studies of specific K+ channel of cells. OBJECTIVES: Given the  lack of information of the molecular biology of peptides in the toxin of Iranian scorpions, the aim of this study is Amplification and Analyses of cDNA sequence coding for a peptide toxin from the venomous gland of the Khuzestan province scorpion Mesobuthus eupeus. METHODS: Total RNA was extracted from the venom glands of scorpion Mesobuthus eupeus collected from  Khuzestan province of Iran and then cDNA was synthesized with the modified oligo (dT) primer. By applying the Semi-nested RT-PCR using homologous primers, the fragments of 227 bp were amplified and sequenced. RESULTS: The full-length sequence of coding region was 174 bp which  contained an open reading frame of 57 amino acids with a predicted molecular mass of 6.434 KDa and theoretical pI of 5.12. It contains a signal peptide of 19, propeptide of 4 and a mature peptide of 34 amino acids. For comparison of this peptide with the similar sequences registered in NCBI database, BLAST program was used. This protein with homology to the “Scorpion toxin-like domain” belongs to the Toxin-6 super family. CONCLUSIONS: Multiple alignment of the putative amino acid sequence of this gene exhibited the highest sequence identity with lesser Asian scorpion M. eupeus venom potassium channel α-toxin-1. This high sequence similarity indicates that this gene is a member of α-toxin from the Iranian Mesobuthus eupeus.