Iranian Journal of Veterinary Medicine
Volume:8 Issue: 2, Spring 2014

Newcastle disease virus (NDV) is the causative agent of the Newcastle disease (ND), a highly contagious disease in birds that causes significant economic losses to the poultry industry worldwide. ND is endemic in Iran and outbreaks are reported regularly in commercial poultry flocks and different species of birds. The current study was carried out to characterize NDV based on phosphorprotein (P) gene from recent outbreaks in Iran, 2010-2012. The P gene fragment of NDV isolates of five chickens, 1 ostrich, and 1 Pigeon paramyxovirus-1 was obtained by RT-PCR and sequenced. Phylogenetic analysis of sequences revealed that chicken and ostrich NDV isolates were closely related and placed in the genotype VII and Pigeon Paramyxovirus-1 was located in the genotype V. This is the first report of Phosphoprotein gene sequences of NDV strains isolated in Iran. This study will help us to understand the epidemiology and molecular characteristics of Newcastle disease virus in Iran.

Linguatula serrata, a tongue worm, is an aberrant cosmopolitan parasite, which inhabits the canine respiratory system (final host). The discharged eggs infect many plant feeder, including ruminants and human being, that produce visceral and nasopharyngeal linguatulosis which is known as Marrara syndrome in man. In the current study, the prevalence rate of infection with L. serrata nymphs in mesenteric and mediastinal lymph nodes (MLNs) of slaughtered goats was investigated by cutting in MLNs and observing them in Isfahan Province, Iran. The MLNs of 620 slaughtered goats, including 197 females and 423 males, after the preparation of the lymph nodes, were examined for L. serrata nymphs by cutting them longitudinally and testing them by using a dissecting microscope for L. serrata nymphs. Then, in the suspected cases, the samples were digested by pepsin and hydrochloric acid and were examined for presence of L. serrata nymphs. Goats were categorized into four age groups, including < 1.5 year, 1.5 to 2.5 years, 2.5 to 3.5 years, and > 3.5 years. The results showed that 54.35% of the examined goats were infected with L. serrata. Sex had no significant effect on the prevalence rate of this parasite in goats. Ahigh prevalence rate of infection in goats suggests a possible similar high rate of infection in other animals and man in the investigated area, which emphasizes undertaking strict control measures to reduce the risk of zoonotic outbreaks.

Neonatal calf diarrhea (NCD), also known as calf scours, is caused by viruses, bacteria, and parasites. Coronavirus is one of the important causes of NCD syndrome. Electron microcopy has been used for demonstration of viruses in fecal samples of diarrheic calves since 1969.

The aim of this study was to determine the prevalence of coronavirus in fecal samples of neonatal calf diarrhea using electron microcopy examination of fecal samples.

For the purpose of this study, a total of 100 cases (under 2 months of age) of diarrheic calves from 25 commercial farms in four districts of East Azerbaijan province of Iran were used. Fresh Fecal samples using sterile swab were collected from every calf with clinical diarrhea. All samples were transferred into a sterile container and then were sent to the laboratory to be kept in -20oC freezer until examination. Electron microscopic examination was applied to all fecal samples. Chi-square test was used to analyze the data.

According to the results of this study, coronavirus was present in 15% of cases and a significant difference was found between the prevalence rate and the seasons (p<0.05). The highest prevalence was recorded in winter (28%) and the least prevalence was seen in summer (4%). There was not any significant difference in both age groups and different districts according to the prevalence rate of infection.

Neonatal calf diarrhea is a multi-etiological syndrome. Among the viral diarrhea, bovine coronavirus is one of the major causes of this syndrome. For detection of coronavirus in feces, electron microscope examination is a gold standard diagnostic technique. It seems that coronavirus can be considered as one of the important etiologies of neonatal calf diarrhea in east Azerbaijan of Iran.

Betaine has been shown to be antioxidant and methyl donor effects in our recent studies. In the present study, the antioxidant and methyl donor properties of betaine in levodopa/benserazide-mediated hyperhomocysteinemia and levodopa-induced oxidative stress in rat's kidney were examined. Sprague-Dawley male rats were divided into levodopa (LD), Betaine (Bet.), levodopa plus betaine (LD/Bet.), levodopa plus benserazide (LD/Ben.), levodopa plus betaine-benserazide (LD/Bet.-Ben.), and control groups. The experimental groups received LD (3 × 100 mg/kg), Bet. (1.5% w/w of the total diet), Ben. (3 × 25 mg/kg), and distilled water was given to controls for 10 consecutive days, orally by gavage. Plasma total homocysteine (tHcy) concentration decreased significantly in Bet.-, LD/Bet.-, and LD/Bet.-Ben.- treated rats compared to LD/Ben. group. Thiobarbituric acid reactive substances concentration (as a lipid peroxidation marker) in renal tissue reduced statistically in betaine group in comparison with LD and LD/Ben. groups. Renal catalase activity increased significantly in LD-treated rats when compared to controls. Renal superoxide dismutase activity significantly decreased in LD-treated group when compared to LD/Ben. group. However, there was not any significant difference in renal glutathione peroxidase (GPx) activity among the groups. These findings indicate that LD and LD/Ben. have side effects in kidney due to induction of hyperhomocysteinemia and oxidative stress. In contrast, betaine acts as a promising antioxidant and methyl donor agent versus LD-induced complications.

Cardiovascular system is a very important organ that plays a vital role in tissue function. In farm animals, the growth and high milk production depends on function of cardiovascular system. Cardiovascular health in high and low-yielding dairy cows was investigated. Fifty 4-year-old high- yielding Holstein dairy cows and fifty 4- year-old low- yielding Holstein dairy cows were used in this study. Electrocardiogram was recorded by a base- apex lead, and blood samples were collected from the jugular vein for the measurement of cardiac biomarkers (CK (Creatine Kinase), CKMB (Creatine Kinase-Myocardial Band), LDH (Lactate Dehydrogenase), and AST (Aspartate Aminotransferase) and troponin I). Cardiac dysrhythmias were detected more in low- yielding Holstein dairy cows (62%) compared to highyielding Holstein dairy cows (46%). The cardiac dysrhythmias that were observed in low- yielding Holstein dairy cows included sinus arrhythmia (34.7%), wandering pacemaker (22.45%), sinus bradycardia (18.37%), sinus tachycardia (10.20%), atrial premature beat (2.04%), sinoatrial block (2.04%), atrial fibrillation (8.16%), and atrial tachycardia (2.04%). The cardiacdysrhythmias were observed in high- yielding Holstein dairy cows, including sinus arrhythmia (86.95%) and wandering pace maker (13.05%). Also, notched P wave was observed in highand low- yielding Holstein dairy cows, 30% and 14% respectively. The amount of cardiac biomarkers in the low yielding cows was significantly higher than that of the high yielding cows. Further more, there was not any detectable significant difference of serum concentration of total CK between the high and low- yielding Holstein cows. Despite significant differences in cardiac biomarkers and based on the normal range of cardiac biomarkers in both groups, the increase in cardiac dysrhythmias in low- yielding Holstein dairy cows may be metabolic and electrolyte disorders.

Disruption of testicular function and arrest of spermatogenesis are the consequence of cryptorchidism in response to elevated temperature. This investigation was set to clarify the possible ghrelin efficacy in altering some sperm quality parameters upon experimentally-induced cryptorchidism. Thirty male adult rats were scheduled for the study and were divided into three groups: group 1 was served as control-saline (CS), group 2 was designed as cryptorchidism-saline (CrS), and group 3 was defined as cryptorchidism-ghrelin (CrG). After surgically inducing cryptorchidism in groups 2 and 3, the researchers gave 10 nmol of ghrelin to CrG rats for 7 consecutive days. Five animals in each group were equally killed on days 3 and 7 after operation and their testes were taken for sperm evaluation. Testicular weight, sperm forward progressive motility (FPM), functional membrane integrity (assessed by HOS-test), and sperm concentration displayed slight changes after heating on day 3. However, abdominal position of the testes for 7 days caused a significant reduction in the percentages of HOS-positive cells (p<0.0001), FPM (p<0.0001), and sperm concentration (p<0.01). Although a 30% decrease occurred in the testicular weight at this point, however, this reduction was not statistically significant. Interestingly, HOS-test and FPM percentages were significantly higher in the ghrelin-exposed animals compared to the CrS group on day 7 (p<0.05). However, ghrelin treatment had not considerable influence on sperm parameters by day 3. Moreover, sperm concentration and testicular weight did not exhibit any changes either on day 3 or at day 7 upon ghrelin injection (p>0.05). Indeed, this function of ghrelin could be attributed to its antioxidant properties and it may be implicated as a potential agent in attenuation of impaired spermatogenesis after cryptorchidism.

Tetracyclines (TCs) are broad-spectrum antibiotics that are widely used in veterinary medicine. The presence of TCs residues in milk is a public health concern all over the world. This study aimed to determine TCs residuals in pasteurized milk marketed by some dairy companies in Tehran from April 2011 to March 2012. 432 pasteurized milk samples were purchased from supermarkets supplying the milk products of 12 major dairy companies in Tehran (3 samples from each company every month), and they were stored at -20 0C until analysis. Oxytetracycline (OTC) and Tetracycline (TC) residues in each sample were extracted by a liquid - liquid phase procedure and quantitated using a high performance liquid chromatographic (HPLC) method. Chromatographic conditions included a mobile phase as oxalic acid buffer- acetonitril (80: 20) with a flow rate of 1mL/min and UVdetection at 355 nm. TCs residuals in most milk samples were lower than 100 ppb, maximum residue level (MRL); however, in seven samples (1.62%) the total residues of OTC and TC were more than MRL. In the latter milk samples, the median total TCs residue was 625 ppb, ranging between 274 and 1270 ppb. Because of the presence of TC residues above the MRL level in a limited number of milk samples, it is concluded that more studies and supervision of health authorities are needed in this field.

Occurrence of resistance against antibiotics and inadequate efficacy of some vaccines necessitates studies of natural immunostimulators in aquaculture. Shrimps shell derived from Chitosan can be used as immune stimulators in fish. In this study, the effects of oral administration of chitosan, derived from shrimp shell, on some immune responses and disease resistance in Cyprinus carpio were studied. Three hundred healthy fish weighing 42.4+8.1 g were divided into 4 equal groups: the first group (G10) was fed with food supplemented with 10 mg kg-1 chitosan, the second (G5) and third groups (G2.5) were fed with food supplemented with 5 mg kg-1 and 2.5 mg kg-1, respectively. The control group was fed with basal feed (without chitosan). All groups were treated for 60 days. Blood samples were taken on 0, 20, 40, and 60 days post- experiment; In addition, some immunological indices, including serum lysozyme activity, serum bactericidal activity, Nitro Blue Tetrazolium (NBT) reduction activity, serum proteins, white blood cell count (WBC), and differentiated count were measured. At the end of the treatment, fish were challenged with live Aeromonas hydrophila and mortality rate was recorded for 14 days. Oral administration of chitosan (0.5 and 1%) significantly enhanced NBT reduction activity and resistance to A. hydrophila infection (p=0.012). Serum lysozyme and bactericidal activity, serum total protein and globulin, WBC and leukocytes ratio showed no significant change among the groups (p>0.05). This study indicates that oral administration of shrimp shell chitosan may have a positive effect on some immune parameters and resistance against bacterial infection in Cyprinus carpio.

Aflatoxin B1 (AFB1) is a toxic metabolite produced by Aspergillus species that contaminates a wide range of agricultural products. This study was designed to develop a rapid and highly sensitive immunoassay method in microarray format for quantitative detection of AFB1 to evaluate the potential of microarray platform for high-throughput screening, which can be beneficial in food and feed industry. Following successful optimization, using an indirect competitive immunoassay in dot blot format, AFB1-bovine serum albumin (AFB1-BSA) conjugate was contact-printed onto 16 isolated subarrays on multi-pad nitrocellulose coated slides; subsequently used in competitive binding assays. Using the aforementioned assay, AFB1 was determined from 15 pg/g to 3.04 ng/g working range with detection limit (LOD) of 1 pg/g. To evaluate assay performance in real food matrices, the authors spiked wheat samples with different concentration of AFB1. After extraction, working ranges of 0.11-4.15 ng/g with detection limit of 30pg/g was determined. Good recoveries (94±9%) were obtained, demonstrating accurate detection of AFB1 concentrations in wheat samples. Assay procedure completed in 3 hours. The results indicated that the proposed developed assay in microarray format could be used for rapid and sensitive detection of AFB1in wheat samples.

Perosomus elumbis is an occasional congenital anomaly of cattle, swine, sheep, and dogs with unknown etiology. This congenital abnormality occurs in both sexes. A dead Holstein calf characterized by musculoskeletal and external genitalia abnormalities was referred to the large animal hospital of University of Tehran. Radiographic evaluation and subsequent dissection revealed that the vertebral column was truncated at the level of first lumbar vertebra (L1). Moreover, L2-L5, sacrum and coccygeal vertebrae were absent. The dorsum of the lumbosacral region contained only soft tissues. Urogenital tract was incomplete, and it contained agenesis of the ovaries, uterine tubes, cervix, and vulva concurrent with unilateral umbilical artery agenesis. Small and large intestine contained blind-ended sacs. No testes, scrotum, and penis were found. The intact ureter was attached to a thin-walled fluid fill sac. The laboratory finding showed that the pH of the fluid was 6 and contained hemoglobin, white blood cells, bacteria, a few red blood cells, oxalate crystalline, and epithelial cells. It was concluded that the collected fluid was urine. This is the first report of perosomus elumbis in a Holstein calf having a lot of visceral abnormalities in Iran.