The objective of the present study was to investigate the effects of a sustained-release multi-trace element ruminal bolus on sex ratio, the reproductive performance and lambs growth of Afshari ewes. Eighty Afshari cycling ewes during breeding season were used in the trial. The animals were synchronized using CIDR for 14 days and assigned into 4 groups including: group 1 (n=20) received a single Ferrobloc bolus four weeks prior to CIDR insertion following 400 IU eCG on CIDR removal, group 2 (n=20) received two boluses four weeks prior to CIDR insertion following 400 IU eCG on CIDR removal, group 3 (n=20) received only 400 IU eCG on CIDR removal and group 4 (n=20; control) received no bolus and no eCG. Growth traits were analyzed using the mixed procedure of SAS. Number of observations (lambing rate, litter size, barren rate and the male / female lamb rate) in different groups was compared using the Chi-Square test. Results showed that ruminal bolus can play an indirect role in skewing sex ratio toward male offsprings. Given 1 or 2 sustained-release multi-trace element ruminal boluses four weeks before synchronization programme using eCG, causes the pregnancy of all ewes. Of the four treatments tested, the 2 boluses+eCG showed superiority on reproductive performancein terms of lambing rate (150%) and litter size (150%) in Iranian Afshari ewes during breeding season. Also, bolus supplementation enhances lamb body weight at birth up to 60 days of age.

Listeria monocytogenes is an important food borne pathogen with a high case fatality rate. Among 13 different serotypes of this bacterium, 4 serotypes (1/2a, 1/2b, 1/2c, and 4b) were considered as the main cause of listeriosis outbreaks. The aim of this study is to identify the major serotypes and virulence genes in Listeria monocytegenes isolated from chicken carcasses which were collected from different supermarkets and butcheries in Mashhad. Among the 80 isolated Listeria spp., most of them were identified as L. monocytogenes (36 out of 80). Most of the L. monocytogenes isolates belonged to serogroup llb (52.77%) which contains 1/2b and 3b serotypes. The second and third major serogroups were IVa (27.77%) and IIa (16.66%). Serogroup IVb (2.77%) which contains 4b serotype was the fourth major isolate. In order to differentiate serotype 1/2a and 3a from 1/2c, amplification of flaA gene was used. L. monocytogenesis isolates were also examined for the presence of inlC, inlJ and hlyA virulence genes. 26 out of 36 isolates were positive for inlC, and inlJ, whereas hlyA gene was detected in 32 isolates. Chicken carcasses may act as a source of infectious listeriosis for humans living in this area.

Probiotics have shown beneficial effects on growth parameters of various food animals. In this research, the growth promoting effects of a multi-strain probiotic was investigated on common carp (Cyprinus carpio). Accordingly, 200 fish (6-7g) were randomly allocated to 4 experimental groups. The first group received placebo and was served as the negative control. The second group received the prebiotic Fermacto at 3g/kg diet and was considered as the positive control. The remaining 2 groups received a multi-strain probiotic (PTX) at 75 and 150mg/kg feed, respectively. The body weights and lengths of all fish were measured at the end of the experiment (day 45). The amounts of protein, fat, ash and dry matter of fish meat were analyzed in all experimental groups (n= 6 each). The probiotic, at 75mg/kg feed, significantly increased the body weights and lengths, as well as the condition factor. Consistently, the feed conversion rate was lower in PTX treated groups. The percentage of meat fat was significantly lower in groups receiving either the probiotic at 150mg/kg feed, or Fermacto, compared to the control. The fish receiving PTX at 150mg/kg feed showed significantly higher amounts of meat protein. The levels of meat ash and meat dry matter were not statistically different compared to the control group. The present study suggests that PTX, at 75mg/kg feed, is effective in improving the growth and feed conversion rates of common carps

Colibacillosis is of the most common infectious bacterial diseases of poultry.A total of 170 Escherichia coli isolates obtained from broiler and layer flocks implicated with colibacillosis between 2011 and 2014 were subjected to phylogenetic analysis. Among 150 E. coli isolates from typical lesions of local and systemic colibacillosis, 54 (31.8%), 37 (21.7%), 36 (21.2%) and 43 (25.3%) isolates determined as belonged to groups A, B1, B2 and D, respectively. The distribution of phylogenetic types for 20 isolates, obtained from apparently healthy birds as controls, were 9 (45%), 5 (25%), 1 (5%) and 5 (25%) for A, B1, B2 and D, respectively. Overall, the phylogenetic Determination revealed the B2 groups as predominant isolates in diseased birds, whereas the A group was apparently predominant in healthy birds. Results of this study represent genotypic diversity among different manifestations of avian colibacillosis.

Fleas are the most common and important external parasites worldwide and also serves as vectors of various pathogens for humans and animals. The study aimed to determine the prevalence of Pulex irritants in sheep herds and residential areas of villages in Kurdsitan Province, Iran. A total of 2,900 sheep were randomly selected from 48 flocks and 630 residential areas of 18 villages from November 2011 to October 2012. The collected fleas were identified by key fleas. Results revealed that 259 (8.93%) sheep from 31 flocks (65.51%) and 31 (4.92%) residential areas were infested with P. irritants. Of 1323 P. irritants, 503/1323 (38.02%) and 820/1323 (61.98%) were male and female, respectively. Of these, 950 (72%) were from animals and 373 (28%) were from residential areas. The highest infection rate was found in age group less than one year (30.93%, 29/92). The body distribution of all collected flea was found to be from back part of the body (100%). Seasonal distribution of P. irritants in examined animals had significant difference. Geographical distribution of P. irritants indicated that the highest infection rate was found in Marab region (6.03%). The highest flea infestation was also found in summer (41.8%) with a total number of 450 fleas out of 1323 (34.01%). From the results of this study, it was concluded that P. irritants was a prevalent flea in sheep and residential areas in the region and may serve as an important vector for pathogenic agents.

Argas reflexus is considered obligate blood feeder that may cause skin redness and local swelling. For histopathological evaluation of biting site, pigeons were used as natural host species in this study. Adult ticks were collected from Urmia, North-west of Iran and kept in a desiccator before their use in the experiment. Sixteen Pigeons were infested experimentally and were divided into 4 groups, euthanized after 30 min, 4, 24 and 48h for evaluation of histopathological changes in biting sites. Early histopathologic lesions due to time of infestation included edema, hemorrhagic foci, vascular congestion, necrosis and mild to severe inflammatory reaction in dermis. In late lesions, presence of micro abscess foci in dermis was prominent. This study well documented the different pathological changes of skin of pigeons with Argas reflexus. However, further study should be performed to evaluate allergic immune responses and pathological changes in other animal species including human.

Identification of exogenous factors affecting spermatogonial stem cells (SSCs) proliferation in vitro, provides worthy ways to study the basic biology of the cells. The aim of this study was to investigate the effects of a GnRH analogue (alareline acetate) on SSCs colonization in short-term co-culture with sertoli cells. Five, three-month old Holstein male calves were used to isolate spermatogonial and sertoli cells. Testicular germ cell collection was made by enzymatic digestion methods. The cells were co-cultured in a 15 day period and in vitro effects of various doses (0.5, 1, 2 and 4 µg/ml) of GnRHa on SSCs colonization were assessed. Effects of GnRHa on SSCs proliferation were dose dependent. In conclusion, it was demonstrated that 1 µg/ml GnRHa was the optimum dose for SSCs colonization in comparison with control group. The highest treatment dose (4 µg/ml GnRHa), negatively affected SSCs colonization in comparison with control group.

Although there are many evidences regard to the relationship between serum thyroid hormones, cholesterol, triglyceride and lipoproteins in different animals, but there are limited references in dogs. The aim of this study was to determine the correlation between thyroid hormones and concentrations of serum lipid and lipoprotein profiles, and also to detect relationship between the measured parameters in different season, sex and age groups of dogs in Ahvaz district, Southwest of Iran, on 2011. Blood samples were taken from the cephalic vein of 60 clinically healthy and non-pregnant native dogs in two seasons (summer and winter) and in two age groups (3 years). Sampling was done only once from each animal (30 dogs in every season). The serum concentrations of cholesterol, triglyceride (T.G), very low density lipoproteins (VLDL-cholesterol), low density lipoproteins (LDL-cholesterol), high density lipoproteins (HDL-cholesterol and their correlations with thyroxine (T4) and triiodothyronine (T3) hormones were measured in the studied dogs. The mean serum concentrations of cholesterol, triglyceride, HDL-cholesterol, LDL-cholesterol, VLDL-cholesterol (mmol/L), T4 and T3 (µmol/L) were measured in the present survey. The above parameters were also obtained in two summer and winter seasons. Season had a significant effect on T.G, HDL, LDL and VLDL levels in the studied dogs (p0.05). No significant differences were detected for the measured cholesterol, T3 and T4 parameters in different age, sex and season groups (p>0.05). To the best of our knowledge, there was no previous research regarding the correlation of the thyroid hormones with the serum lipids and lipoproteins in dogs in Iran. Our results showed that thyroid hormones affect T.G, HDL, LDL and VLDL levels and observed seasonal change in serum may be partly due to changes in thyroid hormones.

Cobalt is an essential co-factor in red blood cell production and function and its deficiency may produce clinical signs in sheep. Thus, present study was designed to evaluate the effect of cobalt nano-particles on serum biochemical factors and histopathological changes in liver and kidnies of lambs. Study was carried out in 3 groups of lambs (4 lambs per group). One group of lambs was kept as control group. Second and third group respectively received cobalt nano-particles and conventional cobalt chloride suspension daily for a period 25 day. Blood sample and then serum was collected before and at the end of study. Activity of ALT,AST, ALP and level of BUN, creatinine and vitamin B12 were measured in serum of lambs. Tissue sections of liver and kidney were stained with hematoxylin and eosin and examined by light microscopy. Activity of ALT, BUN and vitamin B12 was significantly increased by cobalt nano-particles and conventional cobalt chloride. Fatty change of hepatocytes occured by conventional cobalt and granulomatous hepatitis, focal necrosis of hepatocytes and degeneration of hepatocytes by the nano cobalt was identified in liver. There were not any significant lesions and alteration in the kidnies of treated groups. Thus, cobalt nano-particles have similar effect to conventional cobalt for using in sheep with cobalt deficiency.

BVDV and BHV-1 are considered as worldwide, complicated and economically significant infections associated with a range of clinical syndromes in cattle. As clinical syndromes such as pneumonia, diarrhea, abortion and reproductive losses were repeatedly reported in dairy herds in suburbs of Arak, this study was planned to determine the prevalence of antibodies to BVDV and BHV-1 in industrial dairy herds in the region. For this purpose, a total of 803 serum samples from 12 non-vaccinated herds were collected between June to October 2008 and evaluated for BVDV and BHV-1 antibodies using commercially available ELISA kits. Antibodies were detected against BVDV in all herds, but only one herd was free from BHV-1. The prevalence rate of 54.3% and 35.6% was estimated for BVDV and BHV-1, respectively. In addition, statistical analysis showed significant associated seropositivtiy to both infections. The results notably exhibited that both BHV-1 and BVDV infections are highly prevalent in the region, indicating that control measures should be implemented to reduce the prevalence rate of these infections.