Iranian Journal of Veterinary Medicine
Volume:7 Issue: 1, Winter 2013

Colibacillosis is one of the most prevalent diseases in the world that causes multimillion-dollar annual losses. In order to evaluate molecular epidemiology of some virulence associated factors in Escherichia coli, isolated from poultry, the presence of iut A, iss, hly F, omp T, iro N, afa, sfa (S)and pap G (II) were investigated by multiplex PCR assay. Two hundred thirty four Escherichia coli isolated from avian colibacillosis (APEC) and fifty four fecal E. coli isolates from the feces of apparently healthy birds (AFEC) were investigated for presence of some virulence associated genes by two panel of multiplex PCR. Statistical analysis was performed using |c 2 test. the p-value was |£|0.05. Among 234 E. coli strains associated with colibacillosis and 54 AFEC strains, 85% of isolates were positive for at least one of the virulence gene. The three most prevalent genes in E. coli isolated from colibacillosis were hly F (77.3%), omp T(73%) and iss (68.2%). Iut A, iro Nand pap G (II) were detected in 157 (67.4%), 152 (65.2%) and 41(17.6%) respectively. None of isolates harbored sfa (s) and afa genes. Several combination patterns of virulence genes were detected. Combination of hly F, omp T (70.8%) was the most prevalent pattern. the prevalence of iss, hly F, omp T, iro N genes in APEC isolates was significantly more than AFEC strains and probably these genes play an important role in the pathogenesis of APEC strains.

Bone marrow-derived mesenchymal cells can transdifferentiate into Cardiomyocyte cells and improve heart function after transplantation. Since biomaterials can improve the cell retention in the site, cell survival and differentiation, heart tissue engineering is now being explored as an applied solution to support cell-based therapies and increase their efficacy for myocardial diseases. Chitosan in combination with Glycerol Phosphate (GP) can produce a thermo sensitive material that in body temperature can form a jellylike material.The aim of this study was to evaluate the effects of a combination of autologous undifferentiated bone marrow mesenchymal stem cells (MSCs) and injectable scaffold on cardiac function improvement in rabbits after inducing myocardial infarction. The Left Anterior Descending (LAD) coronary artery was ligated by No. 6-0 polyamide suture material, and autologous MSCs with injectable scaffold were injected into the margins of the infarcted zone at the time of surgery. At 4 weeks after transplantation, the cardiac function and structure was detected using echocardiography. There was no significant difference among the three groups (MI only, MI Scaffold, and MI+Scaffold+MSCs) in the Echocardiographic parameters including, heart rate (HR), Ejection Fraction (EF), Fractional Shortening (FS), Left Ventricular Diameter (LVD) and Left Ventricular Parietal Wall Diameter (LVPW). A combination of autologous undifferentiated bone marrow MSCs and injectable scaffold made of Chitosan+ Glycerol Phosphate in echocardiographic evaluation did not have a positive influence on achieving functional improvement.

A major issue in many gene expression studies utilizing small amount of biological materials is the limited quantity of RNApurified from clinical samples, which is often used for RT-PCR or standard Northern blot analysis. The SMART cDNA synthesis method and subsequent SMART-cDNA-PCR technique was used to analyse 3 genes in macroschizonts of Theileria annulata in small lymph node biopsy material. The SMART-cDNA of TaSp gene was cloned in pTZ57R/T-vector and sequenced. We focused on genes encoding surface proteins TaSp, TaD and HSP70. Our results showed that SMART cDNA dependably reproduces the expression profile found in messenger RNA. The RT-SMART-PCR showed the amplification of the processed mRNAs. The sequencing analysis showed that the amplified cDNA was coded for TaSp protein in Theileria annulata. It was concluded that the SMART PCR technique is practical for amplification of complete sequence of mRNAs in the form of cDNAs, and therefore for gene expression studies if only small amounts of starting material are available.

The H9N2 subtype of avian influenza viruses (AIVs) have spread in Asia and Middle East countries and have become a serious threat to poultry industry in Iran.Characterization of genes of H9N2 subtype involving in pathogenicity and diagnosis are crucial in control of avian influenza outbreaks. The Nonstructural (NS) gene and its protein products (NS1 & NS2) are important as diagnostic marker, life cycle and pathogenicity of AIVs. The NS gene of five strains, isolated from 1998 to 2010, were completely sequenced and analyzed. All of the examined strains were composed of 890 nucleotides with 230 amino acids. In this regard, only two Iranian strains from GeneBank had 217 amino acids in NS1 protein. All Iranian H9N2 strains subdivided into two distinct sublineages including I and II. Comparative analysis of NS genes of Iranian strains showed that since 2003, they might have originated from Pakistan H7N3 strains; whereas from 2008 they could be originated from Pakistan H9N2 strains. Although the low pathogenic H9N2 subtype has been permanently circulating from 1998 to the present in Iran, phylogenetic analysis of NS genes revealed that sublineage II has circulated more in poultry industry of Iran. These epidemio-logically variations could be related to vaccination pressure due to massive vaccination or NS gene reassortment in rural and backyard chickens.

Salmonellosis is one of the most important zoonotic diseases throughout the world. The purpose of this study was to characterize a large collection of Salmonella isolates from different poultry sources in Iran. A total of 123 Salmonella isolates from different poultry sources were subjected to drug susceptibility test,hemolysin production, motility test, and plasmid profile (50 isolates). Seventy-one resistance patterns were found to 29 antimicrobial agents among 123 Salmonella isolates, in which 81% of isolates were resistant to more than one antibacterial agent. The resistance patterns of 123 isolates to 10 commonly used antibacterials in Iranian poultry industry were also quite variable and included 31 patterns. Four different plasmid patterns were found among 50 Salmonellaisolates. Fifty four percent of Salmonella isolates harbored one or three plasmids with approximate molecular size ranging from 2.3 to 68 kb. No plasmid was detected in 46% of isolates. Aband of 68 kb size was detected in all isolates that harbored plasmid. All isolates were motile but no isolate showed hemolysinproduction. The frequency of resistance to antibacterial agents among avian Salmonella isolates is a majorpublic health concern.

Brucellosis is a febrile zoonotic infection and has worldwide distribution among humans as well as animals. Although the seroprevalence of brucellosis in various animals has been described in Iran, there is only one report on equine brucellosis in the region. This study was carried out to determine the seroprevalence of brucellosis in racing clubs and private horse owners in the south of Iran and risk factors associated with the disease in horses. 312 randomly selected equine serum samples were investigated for the presence of antibodies against Brucella genus, using slide agglutination by Rose Bengal plate test (RBPT), serum agglutination test (SAT) and 2 mercaptoethanol (2-ME) test, using whole cell antigen. PCR assay was also used for detection of clinically suspected cases. Most seropositive horses in this study were asymptomatic. The true seroprevalence of brucellosis was found to be 9.9, 8 and 7% by RBPT, SAT and 2- mercaptoethanol tests, respectively. All horses with history of clinical signs (3.2% of all samples) had RBPT, SAT and 2- mercaptoethanol positive results. It was also revealed that age, sex and a history of contact with ruminants had no effect on acquiring the infection in positive cases. In the PCR, one of the three horses with fistula withers produced amplicon of 450 bp fragment of wbo sequences specific to Brucella spp. field strain. This study showed the seroprevalence of brucellosis in horses of Fars province and it was indicated that the PCR assay may be helpful in detection of clinically suspected horses.

Abortion is one of the most important factors reducing lambing rate and consequently profitability of sheep farms. In addition to financial losses, it is also important from a zoonotic point of view. The aim of this study was to investigate bacterial abortifacient agents in an outbreak of abortion occurring in Afshari sheep in the northwest of Zanjanprovince. Vaginal swab samples were collected from 217 Afshari ewes (129 samples were taken from aborted ewes, 3 samples from ewes with crippled and deformed lambs, and 85 samples from animals that had given birth to healthy lambs) from reported flocks involved in outbreak. Swabs were examined by PCR assay to detect DNAfrom Coxiella burnetii, Chlamydophila abortus, Salmonella enterica, Yersinia enterocolitica, Campylobacter fetus, Brucella ovis and Leptospira interrogans. Based on the results, only DNA of Campylobacter was detected in the samples. A 266 bp fragment specific for Campylobacter was amplified from 51.52% and 34.12% samples belonging to aborted and non-aborted ewes, respectively. Significant presence of the bacterium in aborted ewes (p<0.001) compared to the non-aborted groups with odd ratio of 3, emphasizes that Campylobacter could be involved in the outbreak of the abortion. Considering the importance of the disease, prophylactic measures are needed to reduce the disease. However, further investigations are required to determine the impact of this bacterium in prevalence of abortion in sheep in other areas.

Canine parvovirus (CPV) infection is one of the most common causes of infectious gastroenteritis in dogs and is a highly contagious, often fatal disease. The original virus (CPV type 2) has had some mutations since its emergence and new variants (CPV-2a, 2b and 2c) have been reported from many countries all around the world. Early diagnosis and treatment can profoundly affect the disease outcome. To compare the ability of Immunochromatographic (IC) test to detect CPV infection in 50 PCR positive samples (n=50) with regard to virus strains. 50 rectal swabs (n=50) were prepared from suspicious dogs and subjected to PCR and IC test respectively. The sensitivity of IC test in PCR positive samples was 84% (42 out of 50 samples) and the positive predictive value of the test was 100%. Using PCR, CPV strains in our study were 2a (18/50, 36%) and 2b (32/50, 64%) with the predominance of 2b strain. IC test was also able to diagnose 15/18 (83.3%) of CPV- 2a and 27/32 (84.3%) CPV-2b strain positive samples, which means IC test can detect CPV infections caused by both virus strains (2a and 2b), without significant difference. This study shows that IC test results are relatively reliable for diagnosing CPVinfection in daily veterinary practice and the test is able to diagnose both CPV-2a and CPV-2b which are prevalent strains in Iran.

Several investigations showed cartilaginous cells in fibrous tissue of the free part of the penis in one humped camel. The aim of this study was accurate assessment of existence of cartilaginous cells in penis shaft of onehumped camel. Six camel penises from matured camels more than 3 years-old were collected from an abattoir. Different specimens were prepared from each penis and kept in 10% formalin container for fixation. After passing different stages of histotechnique methods, several slides were prepared from each specimen, stained with Haematoxylin Eosin and studied. Results showed that the majority of cartilaginous cells were inside the collagen fibers of tunica albuginea and around corpus cavernosum and corpus spongiosum of penis and their distributions were dissimilar in different parts of the penis shaft. This survey further showed that in penis shaft length, the majority of cartilaginous cells were inside tunica albuginea, which is surrounded by corpus spongiosum and particularly, the ventral surface of urethra. The number of cartilaginous cells decreased gradually from distal extremity towards the proximal extremity of the body of the penis and increased gradually from external layer of tunica albuginea towards the internal layer of tunica albuginea and centre of corpus cavernosum penis. Existence of cartilaginous cells inside the leaf tissue of the penis was seen with aging and puberty.

Black leg has been reported in a variety of animals, but is of the most importance in cattle and sheep. A20 days old Holstein dairy calf was examined because of anorexia and lameness from 2 days ago. The calf was depressed, tachypneic, tachycardic, and had a body temperature of 38.5ºC. Both hind limbs proximal to the tarsal joint were markedly swollen, firm and painful. No crepitation was noted on palpation. The calf had bruxism, stiffness of gait and unwillingness to move. At necropsy, massive necrosis of thigh muscles which caused dark discolorated tissue with metallic sheen, large amount of thin sanguineous exuda and abundant gas bubbles were evident in the underlying tissues.Histopathologic examination revealed extensive degeneration and coagulative necrosis of muscle fibers and supported a diagnosis of black leg. No vaccination against Clostridium chauvoei was applied in the herd and the calf did not receive notable maternal antibody. Providing sufficient maternal antibody or early vaccination of the susceptible newborn calves should be considered in the endemic regions.