BACKGROUND: Zinc (Zn) is one of the most important essential elements in the body of animals and plants. Zinc plays a significant role in the structure of more than 300 different proteins and in many life supporting biochemical and metabolic processes such as cellular respiration and protection against free radicals. Nanoparticles of zinc are the new form of Zinc used in cosmetic and personal care products and also in livestock feed and food packaging. OBJECTIVES: The aim of this study was to evaluate the effects of several sizes and doses of Zinc nanoparticles on antioxidant defense system in rat compared to controls. METHODS: Zinc nanoparticles (10, 20 and 30 nm) at 3 doses (3, 10 and 100 mg/kg bw) were administrated orally for 28 days among 9 experimental groups (n=5). 2 control groups were treated orally with ZnCl2 (100 mg/kg bw) and normal salin (n=5). After 28 days, the rat decapitated and serum was separated from blood samples. The ferric reducing ability of Plasma (FRAP), thiobarbituric acid reactive substances (TBARS) and activity of glutathione peroxidase (GPx), and superoxide dismutase (SOD) enzymes in serum samples were measured as biomarkers of oxidative stress and compared with control group. RESULTS: This survey showed that zinc nanoparticles cause induction of GPx and SOD activity (P < 0.05) and also increased the level of TBARS (P < 0.05). This assay also showed zinc nanoparticles cause significant decrease in total antioxidant activity of plasma (FRAP) (p<0.001). CONCLUSIONS: Nano Zinc induced oxidative stress in a dose dependent manner in large sizes, while their effects depend on the level of ionization in small sizes.

Background: Diabetes is a metabolic disease that is associated with hyperglycemia and infertility. Previous studies indicate that aloe vera may positively affect the blood glucose and fertility. Objective: the present study was carried out to evaluate effect of aloe vera on serum oxidant/antioxidant activity and reproductive hormones following experimental diabetes. Methods: sixty adults male wistar rats were divided to 5 groups. control group(A) was kept without treatment. Group(E) only received aloe vera gel(400 mg/kg-orally). Experimental diabete mellitus was induced in 3 groups of rats by streptozotocin( 65 mg/kg-Ip). One diabetic group was kept without treatment(B). Another diabetic group received aloe vera gel(400 mg/kg-orally)(C) and another received insulin(10 units)(D). Aloe vera gel and insulin was administration for 30 days then, the rats were anesthetized and blood collected. The amount of malondialdehid(MDA), anti oxidant activity(AOA), glutathion peroxidase activity(GPX), thiol protein(TSH), testosterone, LH and FSH was determined in serum. Results: level of testosterone was significantly decreased while amount of MDA, TSH, GPX and AOA was significantly increased in non-treated diabetic rats. Aloe vera increased antioxidant defense. Conclusions: Aloe vera improves antioxidant activity and reduces diabetic complications. Key words: Diabetes, Aloe vera, Anti oxidant, pituitary – sexual hormones, rat.

BACKGROUND: Toxocara canis is the most prevalent intestinal roundworm of canid species. OBJECTIVES: This study aims to evaluate the effects of Toxocara canis excretory-secretory antigens (TcES Ag) on modulating the immune system in Experimental Allergic Encephalomyelitis (EAE) model. METHODS: Adult worms of T.canis were collected from dogs to obtain excretory-secretory antigens. Female C57BL/6mice divided to four groups (5 mice in each) including: group 1 (MOG +TcES Ag), 2 (MOG), 3 (normal) and 4 (TcES Ag). EAE was induced in groups 1 and 2 using myelin oligodendrocyte glycoprotein peptide. Before EAE induction, TcES Ag was injected in group 1. Twenty nine after EAE induction, mice spleens were removed. Mononuclear cells were cultured and used for RNA extraction.Real Time PCR was performed to evaluate RNA expression levels of T-bet (Th1 lineage-specific transcription factor), GATA-3 (Th2 transcription factor), and FOXP3 (Treg transcription factor). RESULTS: Our results indicated the clinical signs (disability score) of mice in group 1 significantly were decreased as compared to the control group. Gene expression of T-bet in the TcES Ag treatment groupmarkedly were diminished compared to MOG and normal group. The expression of GATA-3 gene in group 1 was lower than that in group 2. CONCLUSIONS: It seems that the TcES Ag may reduce disability score in multiple sclerosis EAE model, and other recombinant antigens should be examined.

BACKGROUND: In mare, different methods of earlier cyclicity induction and hastening first ovulation of the year have been reported. OBJECTIVES: The goal of present study was to investigate the effect of progesterone (Cue-mate®) on synchronization and acceleration the first ovulation of the year in winter anestrous mares under artificial lighting system. METHODS: After detection of anestrus mares, artificial lighting regimen of 16h light was conducted since early December for both treatment and control groups mares. After detecting of 25 mm follicle on the ovary, treatment group mares received Cue-Mate and examined through rectal ultrasound until follicle reached in size of 35mm, when Cue-mate was removed. Daily ultrasound examination and teasing were done until detection of ovulation. RESULTS: Based on our results, no significant difference in rate of ovulation (66% vs 60%) and size of ovulatory follicle were existed between treatment and control group. In addition to, despite of decreasing time interval of follicular growth from 25 mm to 35 mm (8.33±0.88 vs 10.75±2.28 in treatment and control groups respectively) and from each of these sizes to ovulation size, no significant difference was existed between treatment and control groups. CONCLUSION: This was the first preliminary report of investigating the effect of progesterone plus artificial lighting on hastening first ovulation of the year in early winter anestrous. It seems more studies with considering the greater number of mares in different ages are needed.

BACKGROUND: Bovine coronavirus (BCoV) is a primary cause of neonatal calf diarrhea worldwide, and is also associated with acute diarrhea in adult cattle during the winter season, resulting heavy economic losses to both dairy and beef industry throughout the world. OBJECTIVE: The Objective of the present study was to screen the fecal samples for BCoV collected from diarrhea from six geographic region of Iran, with the aim to deepen the knowledge of BCoV prevalence and epidemiology in Iran. MEETHODS: 194 fecal samples from diarrheic calves up to one-month age, based on the geographic area were collected. Samples from all the cases were screened for the presence of BCoV by commercially available ELISA kit. Furthermore, all positive samples were subjected to RT-PCR for confirmation. RESULTS: ELISA examination revealed that 7.2 % of taken samples, were positive. All positive samples in ELISA were also positive in RT-PCR. All samples from northwest, northeast, and west, were negative. The average ages of positive calves were nine days. The average stool scores in positive samples and negative samples were 2.5 and 2.1 respectively. 71/4 % of positive samples had fever. CONCLUSION: The results of the present study showed that the occurrence of BCoV in stool samples of diarrheic calves in dairy farms of Iran is lower than the other reports on the world.

BACKGROUND: The parasitic protozoa Toxoplasma gondii is widely prevalent in humans and warm-blooded animals. Humans are usually infected with T. gondii by ingesting oocysts shed by cats or by ingesting viable tissue cysts present in raw or undercooked meat. OBJECTIVES: This preliminary study was conducted to assess the frequency of Toxoplasma gondii infection in tissue samples of ewes slaughtered in Khorramabad, west of Iran. METHODS: We examined the brain tissue, diaphragm, tongue and masseter muscles of 30 ewes. A nested-PCR which targets the 25–50 copies of B1 sequence has been used for tissue samples. RESULTS: The parasite was identified in 21 brain samples (70%) and 8 muscle samples (26.6%). Twenty-three sheep (76.6%) were infected with T. gondii. CONCLUSION: T. gondii is might be considered as one of the major causes of ovine abortion in this region. According to the result, edible parts of sheep may play a greater role as a source of infection for individuals living in this area.

Introduction: Chlamydiosis is a worldwide zoonotic disease caused by different microorganisms in the order Chlamydiales. The aim of this study was to detect and determine the prevalence of Chlamydia infection in pet and zoo reptiles in Tehran, Iran. Materials and Methods: In a period of 10 months from April 2015 to February 2016, swab samples were collected from cloaca and conjunctiva of 130 pet or zoo reptiles (18 snakes, 81 turtles, and 31 iguanas). A Real Time-PCR assay targeting 23s rRNA of chlamydial organisms was performed to detect chlamydial infection in clinical specimens. Results: No positive sample could be detected in the investigated clinical specimens in the present study. Conclusion: Regarding the negative results which were achieved in this study, reptiles could not be important hosts of chlamydial organisms at least in the region of the present study, Iran, Tehran. Despite the present findings in reptiles, pet and aviary birds were previously shown to be remarkable host of Chlamydia spp. in Iran. Further studies particularly serologic surveys and other PCR methods are needed to thoroughly evaluate significance of the chlamydial infection in reptiles. A rapid, accurate and cost-effective method was applied for Chlamydiaceae spp detection and discrimination of the most significant Chlamydia spp., causing disease complications in reptiles. The results indicated low zoonotic risk of Chlamydia spp in Iranian reptiles.

BACKGROUND: Avian Colibacillosis can lead to important economic losses in the poultry industry. Escherichia coli the causative agent of this disease has acquired resistance to different antibiotics, including tetracycline. OBJECTIVES: This study was carried out to detect the distribution of tetracycline Group І efflux genes genes among E.coli isolates from from avian colibacillosis in Iran by PCR assay .METHODS: A total of 50 E. coli isolates from chicken colibacillosis were characterized by cultural, biochemical and PCR methods. Kirby-Bauer disk diffusion method was used to define the resistance of isolates to tetracycline, then the Frequencies of tetracycline resistance genes (tetA, tetB, tetC, tetG, tetH, tetZ and tetE) were also determined using PCR method. RESULTS: According to biochemical and molecular experiments, 50 isolates from 237 chicken samples were recognized as E. coli. Seventy six(76%) of the isolates, however, were resistant to tetracycline. The distribution of tetracycline-resistance genes among E. coli isolates included tetB(34%) , tetA(26%), tetE(16%), tetC(15%), tetH(12%), tetG(12%) and tetZ(6%). CONCLUSION: The present study highlights the prevalence of tetracycline resistant E. coli among chickens which is due to extensive

BACKGROUND: Accurate identifying and assessment of the degree of pain that the animal is suffering can be a challenge, and, control of painful condition is becoming an increasingly important part of veterinary medicine. OBJECTIVES: This study was carried out to compare different tools for postoperative pain assessment in bitches. METHODS: Ten adult mixed breed bitches were selected and randomly divided into two equal treatment and control groups. Anaesthesia was premedicated with acepromazine (0.03 mg/kg, IM) and induced with Sodium thiopental (6-10 mg/kg, IV). Halothane was used for maintenance of the anesthesia. Ovariohysterectomy performed in the two groups. Treatment group received 3 mg/kg of tramadol intramuscularly (i.m.) and control group received normal saline (equal volume with tramadol, i.m.) before the anesthetic induction. After operation the injections of tramadol and normal saline were repeated for every 6 hours in 7 days. The animals were monitored at hour 2, 3 and 4 after each injection and they were scored for signs of pain by two trained assessors who were blinded to the groups. The measured variables were pain assessment with different methods including Simple Descriptive Scale (SDS), Visual Analogue Scale (VAS), and University Melbourne Pain Scale (UMPS). Duration of anesthesia and duration of surgery, were also recorded. RESULTS: There were no significant differences between the two groups in regard to analgesia that were measured based on VAS and SDS methods, but in UMPS method, analgesia was significantly better in treatment group. Among simple clinical criteria body temperature and respiratory rate did not show any significant alterations, but heart rate had significant changes between the groups. CONCLUSIONS: The ability to quantify the degree of pain experienced by animals is an important aspect in the assessment of animal welfare; in addition, we concluded, that the great challenge for the veterinarians is the evaluation of postoperative pain in dogs

BACKGROUND: Bacterial resistance to antibiotics is a crucial public health problem. Essential oils (EOs) possess antimicrobial effects and have been screened as potential natural antimicrobial compounds. OBJECTIVES: This study was conducted to compare the effects of Eugenia caryophyllus (clove) and Origanum compactum (oregano) EOs on the growth of Staphylococcus aureus and the expression of the SEA, SEC and SEE genes. METHODS: The minimum inhibitory concentrations (MIC) of EOs and growth of bacterium at subMIC levels of EOs was determined. Enterotoxin detection was done using a commercial SE visual immunoassay kit after 18, 24, 48 and 72 h. Gene expression of enterotoxins was evaluated through RNA extraction, DNA synthesis and performing real time-PCR using specific primers for each SE. RESULTS: MIC of clove and oregano were 2 µl/ml and 1µ l/ml, respectively. Colony counts at 48 and 72h of cultures grown at 75% MIC of clove oil showed the growth rate was reduced 1.67 and 1.83 log10 cfu/ml compared to the control, and in the case of oregano at 75% MIC the decreases in growth rate were 2.25 and 2.68 log10 cfu/ml, respectively. When the target bacterium is cultured in the presence 75% subMIC of EOs, the transcript levels of sea, sec, see and the regulatory gene (agrA) were decreased 8.81, 9.13, 9.08 and 8.32 fold in the case of clove, and 11.56, 9.96, 11.07 and 11.15 fold in the case of oregano, compared to the control. CONCLUSIONS: The growth, gene expression and as a result secretion of enterotoxins A, C and E by S. aureus were decreased significantly at subMIC levels of EOs, especially at 75% MIC.