BACKGROUND: Lead (Pb) induced oxidative stress is known to suppress growth performance in broiler chickens. The current study was carried out in an attempt to describe the specific underlying mechanisms of such phenomenon. OBJECTIVES: The objective of this study was to investigate the effect of Pb-induced oxidative stress on performance, antioxidant status and behavioral responses of broiler chicken. METHODS: Eighty day-old broiler chicks were randomly assigned to 2 dietary treatment groups of 4 pen replicates, namely i) basal diet containing no lead supplement (control) and ii) basal diet containing 200 mg Pb/kg of diet. RESULTS: The results showed that addition of lead decreased body weight gain (p<0.01) and feed conversion ratio (p<0.01). Also, consumption of contaminated diet significantly increased MDA and H/L Ratio and significantly decreased SOD and GPx activity (p<0.01). Moreover, addition of 200 mg/kg diet significantly increased sitting pasture and aggression behavior and decreased feeding behavior (p<0.01).               CONCLUSIONS: Our data conclude that Pb-induced oxidative stress adversely suppressed feed conversion ratio and growth performance. The proposed underlying mechanism for such phenomenon is Pb-induced oxidative stress by impaired antioxidant status and feeding behavior decreased the growth performance.

BACKGROUND: Indigenous chickens could serve as precious genetic resources that should be considered in conservation and breeding programs. The Major Histocompatibility Complex (MHC) has a strong association to disease resistance/susceptibility, production and reproduction traits in chicken. Therefore, identifying its polymorphism in populations under selective breeding could be used for selection of disease resistant and higher productive breeds. MHC association with quantitative traits could be  a result of its linkage with causative genes controlling these traits. Insulin-like growth factor 1 (IGF1) is a candidate marker for phenotypic traits in chicken which are associated with important production and reproduction features. Objectives: Based on this hypothesis, MHC polymorphism and its association to IGF1 gene (as a marker for production traits) were investigated in Khorasan indigenous chicken. Methods: In total, 313 DNA samples that belonged to the Khorasan indigenous chicken were analyzed. LEI0258 microsatellite marker and fragment analysis method was used for MHC genotyping. Single nucleotide polymorphism (SNP) of the IGF1 5’-UTR was detected by restriction fragment length polymorphism (PCR-RFLP) and PstI restriction endonuclease enzyme. Linkage disequilibrium between MHC and IGF1 loci were also determined using SAS/Genetics software and likelihood ratio test. Results: Collectively, 25 different alleles (185-493 bp) and 76 genotypes of LEI0258 microsatellite were identified in Khorasan population. Two alleles, A (PstI -) and B (PstI +) and three genotypes (AA, AB and BB) were identified for IGF1 gene. Significant linkage disequilibrium (p=0.0083) was observed between LEI0258 and IGF1 loci in this population. Conclusions: These results indicate a high MHC genetic diversity in Khorasan indigenous chicken as a valuable genetic resource. Results from MHC/IGF1 linkage study confirm the hypothesis that MHC association with production traits could be as a result of MHC linkage with causative genes controlling the traits.

BACKGROUND: PRP (Platelet-Rich Plasma) is a biological product that has shown significant therapeutic results compared to synthetic drugs and some traditional methods. The advantages of this method include: PRP, compared to other biological materials, is easily prepared in clinic and the safety is high as well. OBJECTIVES: We aimed to investigate the evaluation of histomorphometric properties after injection of plasma. METHODS: Thirty rats were divided randomly into three groups: control group (normal saline), PRP and PPP (Platelet-Poor Plasma) groups. In order to prepare PRP and PPP, blood samples (1cc) were collected through cardiac puncture and were centrifuged. The upper layer consisted of PPP and lower layer consisted of PRP. The 2% calcium gluconate solution (100 µl) was added to platelet-rich plasma (200 µl) layer to activate platelet. After seven days, the dorsal skin samples were collected. They are cut into 5 to 6 μm thickness sections using paraffin embedding method and were stained by hematoxylin, eosin and Masson’s trichrome. The epidermis, dermis and hypodermis layers of skin, the epithelial thickness of hair root sheath, maximum depth of hair follicles, the thickness of the whole skin, the number of sebaceous glands and hair follicles in the specified scale, finally the number of fibroblast cells and the percent distribution of connective tissue fibers were investigated in histometric structure of the skin and skin appendages. RESULTS: The results of this study indicated that systematic and controlled PRP may have beneficial effects on the reconstruction and rehabilitation of the skin and its appendages. CONCLUSIONS: The present study showed that growth factors in plasma especially PRP, could be stimulated connective tissue fibroblast of dermal layer in the skin.

BACKGROUND: The most common metal used in the body is iron and since it may produce ROS, it could potentially be a dangerous substance. OBJECTIVES: Regarding the side effects of nanomaterials such as nano iron particles and possibility of environmental contamination including air pollution with nanoscale iron particle, this study was designed to compare the effects of conventional iron oxide with iron oxide nanoparticles, on certain indexes of ovarian tissue in a rat experimental model. METHODS: This animal model was carried out in 5 groups of female rats, including control, iron oxide (15 mg) and iron oxide nanoparticles (5, 15 and 30 mg). The drugs were intraperitoneally injected daily for 16 days. On the seventeenth day the rats were euthanized by chloroform. Ovarian tissue was removed, and histological changes and iron accumulation were assessed by special staining and light microscopy. RESULTS: According to our findings, folliculogenesis was decreased in all groups receiving iron. The number of corpus luteum in the groups receiving different doses of nanoparticle was reduced and the number of atretic follicles was significantly increased in all groups compared to the control group. CONCLUSIONS: In conclusion, probably iron nanoparticles with impaired cellular oxidative pathways, reduces the number of follicles and corpus luteum and increase atretic follicles by producing oxygen free radicals and destructing microfilaments. This can cause a negative effect on the fertility of female rats.

BACKGROUND: Diazinon is an organophosphate pesticide which is widely used in paddy fields located in northern parts of Iran, though it is prohibited to be used in many countries. OBJECTIVES: The purpose of the present study was to investigate sublethal effects of diazinon on blood parameters of common bream Abramis brama. METHODS: In sublethal toxicity test, fish were exposed to diazinon concentrations of 0.04, 0.36, 0.73 and 1.46 mg/l for 14 days and their hematological parameters including WBCs, white cell differential count, RBCs, Hct, Hb, MCV, MCH and MCHC were studied.  RESULTS: The results of sublethal toxicity indicated that by increase of toxicant concentration a significant decrease was appeared in WBCs, RBCs, Hct, Hb and MCH both after 7 and 14 days (p<0.05). After 7 days a significant decrease was observed in lymphocytes count which accounted for about %81 of the control group. The neutrophils count was also face the same reduction so that after 14 days of diazinon exposure, the neutrophils counted decreased to about %85 of control group. CONCLUSIONS: Regarding the toxicity of diazinon on various hematological parameters and the diazinon concentration in Iranian waters and considering the fish habitat in the waters which are connected to the Caspian Sea it suggests that the pesticide diazinon affect the fish survival.

BACKGROUND: This study was conducted to evaluate the effect of melatonin on semen quality and quantity changes and increase of reproductive efficiency in Lori-Bakhtiari ram in the non-reproductive season. OBJECTIVES: The purpose of this study was to investigate the effect of melatonin on testicular size and semen qualitative and quantitative changes in the non-breeding season is Lori-Bakhtiari rams. METHODS: This study was designed to evaluate the effects of melatonin on the quantity and quality of semen and testicular diameter in 8 Lori- Bakhtiari rams (4 control rams and 4 treatment rams) for 10 weeks during spring 2013. Each ram in the treatment group was received three tablets of 18 mg implantable melatonin subcutaneously at the base of ear after 5 weeks from the start of the trial. RESULTS: Semen parameters and testicular diameter measurements were evaluated on a weekly basis. No significant differences were observed between 2 groups before melatonin implanting. A significant difference was observed after melatonin implanting between 2 groups in the mean of testicular diameter (treatment: 33.5±0.25 and control: 30.67±0.07 cm), in semen volume (treatment: 1.34±0.03 and control: 0.87± 0.04 ml) and in sperm concentration (treatment: 1.76±0.05 and control: 1.37±0.04 109/ml) (p<0.05). However, other parameters including average of lives sperm percentage, total sperm motility, sperm progressive movement and percentage of abnormal sperm were not significant (p>0.05). CONCLUSIONS: The results of this experiment showed that the use of melatonin in the non-reproductive season resulted in increase of testicular size, semen volume and sperm concentration in Lori-Bakhtiari ram. However, the rest of the semen parameters have not been affected.

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: In recent years, use of herbs as dietary irritant growth factors and replacing it with artificial materials in aquaculture is discussed. Rosemary (Rosmarinus officinalis) oil is one of herbal medicines which its antioxidant and antibacterial properties have been proved in humans and animals. So it can be an alternative option in order to achieve artificial growth stimulants properties. OBJECTIVES: The purpose of this study was to investigate the effect of different levels of rosemary oil as a medicinal herb on growth parameters and gut morphology of beluga juveniles (Huso huso). METHODS: Six groups (three replicate/group) of 126 fish with initial mean body weight of 130.94 ± 5.28g were fed with diets containing 0 (control), 0/01, 0/1, 1 and 2 % of rosemary oil and a group of oxytetracyclin (30mg/kg) for 8 week. At the end of the trial, the growth parameters (final weight, specific growth rate and feed conversion ratio) were calculated. Then, beluga intestinal biopsy was performed and the mean villi length, width and surface were measured in the treatments. RESULTS: Significant increase were observed in villi length (2/25±0/11mm), width (0/52±0/01mm) and surface (1/17±0/07mm) in fish fed with diets containing 1ml/kg rosemary oil (p<0/05). There were no significant differences in growth parameters between treatments. CONCLUSIONS: According to the significant increase of beluga intestinal absorption area and slight improvement of growth parameters in fish fed with diets containing rosemary extract compared to the control group, it seems that rosemary oil can act as a growth stimulant. So it can be considered as an alternative to artificial growth stimulants in aquaculture industry.

BACKGROUND: Excessive use of antibiotic growth promoters leaded in the creation of antibiotic-resistant bacteria and by consuming animal products, humans are at risk of receiving their residual. Therefore, instead of using antibiotics as growth promoters, some alternatives must be identified and introduced to animal breeders. Objectives: The purpose of this research was to study the effect of anise seed on performance, digestibility, and infectious microbes in the intestine of suckling calves. Methods: Twenty four female Holstein calves with average weight of39.8±3.8kg from the fourth day after birth to two weeks after weaning were examined in a completely randomized design to evaluate the effects of anise powder on dry matter intake, weight gain, age and weight of weaning, feed conversion ratio, apparent digestibility of dry matter, NDF and ADF, and intestinal infectious and harmful bacteria. The diets were: 1- Control, 2- 0.25% and 3- 0.5% anise/DM of diets. Results: Dry matter intake of calves did not affected by diets (p>0.05). At 70 days old the final weight of calves that consumed diets containing 0.25% and 0.5% of anise was significantly more than control diets. There was no significant difference between diets for the mean of total weight gain in whole period of experiment. The digestibility of NDF and ADF after weaning for diets contain anise was significantly more than control diet (p<0.05). Feed conversion ratio did not affected before weaning, but after weaning significantly improved compared with the control group for diet contain 0.25% and 0.5% anise (p<0.05). The age and weight of weaning were not affected by treatments. The Ammonia and pH of rumen fluid showed increase for anise diets compared with the control group (p>0.05). The adding of anise to the diets resulted in significantly decrease of E.coli of intestine of calves. Conclusions: Therefore, use of anise seed as a medicinal herb additive improved the performance of calves. Also, with the decline of E.coli population had beneficial effect on animal health and the environment. So it may be taking into account as good alternative for antibiotics.

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.