IRANIAN JOURNAL OF VETERINARY RESEARCH (IJVR)
Year:2007 | Volume:8 | Issue:4 (21)|Papers Count:20

This study was designed to investigate whether administration of zinc sulphate could improve the response of mouse testis to degenerative effects of short term exposure heating. Fifty-four adult male Balb/C mice were anaesthetized and the scrotums of 36 of them were immersed for 15 min in a waterbath at 43oC. Immediately after the heating, half of the heated animals (n=18) were injected with saline solution (HS) and the other half (n=18) were given 10 mg/kg of zinc sulphate intraperitoneally (HZ), and this was continued every other day for 60 days. Control group of mice (n=18) were treated identical to the HS group with the exception that the waterbath was held at 23°C. Mice were sacrificed at 15, 30 and 60 days after heating and the testes were gently excised. Seminiferous tubules diameter and percentage of spermatogenesis were measured in each testis. There was a significant reduction in the mean seminiferous tubules diameter and the percentage of spermatogenesis up to day 30 after heating in the HS group in comparison with the control group (172.5±2.55 mm vs 208.2±1.53 mm and 18.00±0.77% vs 99.33±0.33%, respectively) but in the HZ group, only initial decline (up to day 15) was observed in the mean seminiferous tubules diameter (199.1±1.90 mm vs 206.0±2.51 mm, not significant) and the percentage of spermatogenesis (91.33±0.95% vs 97.67±0.66%, P<0.001); then, a progressive recovery was seen up to the end of the experiment. Histopathological observations showed progressive degeneration up to day 30 after heating and then normal structure was returned in the HS group. In the HZ group, normal structure was returned up to day 15. The results from this study indicated that administration of zinc sulphate may improve the spermatogenesis process after testicular damage caused by a short term exposure of the mouse testis to heat.

To investigate the relationship between chemical composition of meat from the carcass cuts and the whole carcass, 48 nine-month-old randomly selected ram lambs of Ghezel and Mehraban (24 rams per breed) were used in a trial arranged as a 2x2 factorial experiment with two breeds and two feeding levels (high and low), in a completely randomized design. After 80 days, all animals were slaughtered and the right side of the carcass was cut into the leg, shoulder, back, neck, brisket and flap joints. Dry matter (DM), crude protein (CP), crude fat and ash were determined in meat from individual cuts and combined meat of all cuts (carcass meat). In general, average meat composition was not significantly affected by breed, feeding level and their interaction. Significant correlations were found between chemical composition of meat in most carcass cuts and carcass meat. Carcass DM in Ghezel sheep was highly correlated (P<0.001) with shoulder (r=0.81) and back (r=0.74) meat DM. In Mehraban sheep, back meat DM showed the highest correlation with carcass meat DM (r=0.84, P<0.001). Back CP was significantly correlated with carcass meat CP in both breeds (r=0.80, P<0.001). Carcass meat fat was significantly (P<0.001) correlated with back fat in both Ghezel (r=0.76) and Mehraban (r=0.84). In Ghezel, correlation coefficients of carcass meat ash and other parameters were generally small and non-significant. In Mehraban, carcass meat ash showed a small correlation with shoulder ash (r=0.58, P<0.01) followed by back (r=0.49, P<0.05) and brisket ash (r=0.43, P<0.05). As a whole, chemical composition of the meat in the back joint showed the highest correlation coefficients with the corresponding parameters in the carcass, and may be used as a good predictor of carcass composition in these breeds. Regression analysis of the data indicated that percentages of fat and protein in back meat accounted for about 65% of total variation in carcass meat fat and protein.

The present study was conducted on five healthy male cross bred calves to study the kinetic disposition and urinary excretion of levofloxacin following its single subcutaneous administration at the dose of 4 mg.kg-1. The concentration of levofloxacin in plasma and urine samples was estimated by microbiological assay. Peak plasma level of levofloxacin (2.8 ± 0.3  mg.ml-1) was observed at 45 min and the drug level above MIC90 in plasma, was detected up to 12 hrs of administration. The bioavailability of levofloxacin was 41.9 ± 3.2%. High value of AUC (9.88 ± 0.1 mg.ml-1.hr) reflected a vast area of body covered by drug concentration. Good distribution of the drug was reflected by the high value of Vdarea (0.73 ± 0.04 L.kg-1). The elimination half-life and MRT were 3.0 ± 0.2 hr and 4.79 ± 0.2 hr, respectively. A suitable subcutaneous dosage regimen for levofloxacin was calculated to be 1.25 mg.kg-1 repeated at 12-hr intervals in calves.

To identify the reservoirs of shiga toxin-producing Escherichia coli 0157, sensitive detection and isolation methods are necessary. The sensitivity of traditional culture methods can be improved significantly by the inclusion of an immunoconcentration step, resulting in less false-negative results. In this study, enrichment procedure and immunomagnetic separation (IMS) were compared for use in conjunction with a multiplex polymerase chain reaction (M-PCR) method for detection of genes stx1, stx2, eaeA and hlyA. A total number of 975 faecal samples were collected iTom26 dairy farms in Shiraz area, Shiraz, southern Iran. The samples were cultured at 370C for 18-24 hrs in modified tryptic soy broth (m-TSB). Each of five enriched samples were pooled and examined in two ways-direct PCR and IMS. The detection limit of the M-PCR protocol for seeded E. coli 0157:H7: ATCC: 43895inm-SB withouts tool was 1.23x 102 CFU/ml, whereas it was 1.23 x 106 CFU/ml with enriched faecal sample. In direct PCR of enriched samples, no positive sample was detected. However, in IMS of enriched samples one specimen was positive. The prevalence of E. coli O157:H7 in faeces of cows in examined farms was 0.51% and the herd prevalence was 3.86%. Isolation of this serotype trom faecal sample indicates that cattle are reservoirs of this pathogen and potentially a source of human infection. This finding is of considerable public health importance.

Leptospirosis is a worldwide zoonosis caused by Leptospira interrogans. This study was conducted to evaluate serologic and bacteriologic findings of leptospirosis in clinically-suspected cows. 380 sera and 33 urine samples were collected from 6 industrial dairy farms in Tehran suburb, from December 2004 to June 2005. The prevalence of disease was determined by microscopic agglutination test (MAT), enzyme-linked immunosorbent assay (ELISA), direct dark-field microscopic (DFM) examination, indirect fluorescent antibody test (IFAT), microbiologic cultural isolation technique and polymerase chain reaction (PCR). Antibodies were detected by MAT at least against one serovar of L. interrogans in 55 sera (14.5%) among 380 samples at a dilution of ³1:100. L. interrogans serovar icterohaemorrhagiae was the most prevalent serovar. Leptospiral antibodies were detected by ELISA in 85 sera (22.4%) among 380 samples. Four (12.1%) of 33 urine samples were suspected by DFM examination and no positive sample by IFAT was observed. Leptospires could be isolated from none of the 33 samples taken from industrial farms. In this study, positive controls were detected at a dilution of ≥2000 leptospires per each ml of urine sample by PCR. Therefore, no DNA from serum and urine samples were collected from 6 industrial dairy farms could be detected by this method. It seems that, to increase the accuracy in the diagnosis of the disease, using a range of reliable techniques and comparing the results is important in reaching final conclusion.

To investigate the seroprevalence of leptospiral infection in sheep in Ahvaz, southwestern Iran, blood samples were taken from 181 female sheep. Sera were stored at -20oC until use. They were initially screened at serum dilution of 1:100 against six live antigens of Leptospira interrogans serovars pomona, canicola, hardjo, ballum, icterohaemorrhagiae, grippotyphosa using the microscopic agglutination test (MAT). The samples were considered positive if ³50% of agglutination of leptospire in a dilution test serum of ³l:100 were observed. Sera with positive results were titrated against reacting antigens in serial two-fold dilutions from l: 100 to 1:1600. Antibodies against one or more serovars were detected in 27 (14.9%) sera at dilution ³1:100. Antibodies against more than one serovar were found in 5 (18.5%) positive sera. Among the positive sera, antibodies were most frequent to serovar pomona (43.8%) followed by canicola (21.9%), icterohaemorrhagiae (12.5%), grippotyphosa (9.4%), ballum and hardjo (each of them 6.3%). The results of this survey indicate that leptospiral infection is common in sheep in Ahvaz and that various serovars concur in the etiology.

The objective of this research was to evaluate the cause of fertility reduction after chemotherapy. Cyclophosphamide is a common chemotherapy and immunosuppressive agent used for the treatment of a wide range of neoplastic and some auto-immune diseases. In the present study, morphometrical changes in the ovary and uterus of 12 5–6-week-old female Syrian mice after intraperitoneal injection of 75 mg cyclophosphamide/kg BW were assessed. Control animals (n=8) were injected with sterile distilled water using similar method. The results of this study revealed that cyclophosphamide eliminated almost more than 50% of the primordial follicles (PMF) reserve. The mean±SE number of PMF in the control group was 1210±135 compared to 464±55 in the test group. The mean number of secondary, tertiary follicles and corpora lutea also showed significant (P<0.05) reduction in the treatment group. The histomorphometric studies also showed that the mean±SE diameter of the ovary in the control group was 1703±78 mm as compared to 900.9±86 mm in the test group (P<0.01). The thickness of the uterine wall was also significantly different with a mean±SE of 745.7±13 mm in the control and 393.1±23 mm in the test group. The mean±SE thickness of endometrium in the control group was 392.1±16 mm, whereas in the test group it was 194±10 mm (P<0.001). The results of this study revealed that chemotherapy with cyclophosphamide causes destruction of PMF as well as other growing follicles; accordingly, the reproductive potential was negatively affected. The method used in this study can be most likely used as a sensitive and inexpensive tool to predict the damage to fertility caused by new chemotherapy protocols. In conclusion, chemotherapy brings about a) reduction in ovarian follicular populations, especially PMF, b) it causes reduction in diameter and size of ovary and c) decreases thickness of uterine wall, especially endometrium.

To find the prevalence of domestic and wild animal bites in general, and that of rabies disease in human, in particular in Kerman province, southeastern Iran, a retrospective study was conducted. The necessary data including residence place (urban or rural) of bitten persons, age and job of people were collected during a 10-year period from 21 March 1994 to 21 March 2003 from all regional cities including the urban and rural areas of the province. Data were analysed by chi-square, Fisher's exact test, Pearson correlation coefficient, Student's t-test and Kolmogrov Smironov test using SPSS (v.11.5). The results of the present study showed that the fatal cases of human rabies in the province of Kerman from 1994 to 2003 were 10 persons (8 males and 2 females), half of whom had been bitten by dogs and the others by foxes. No human rabies reported in 1994 in Kerman province. 47% of animal bitten persons had been injured through feet; 41% hands; 7% trunks; 3% faces and 2% through head and neck. From all (21,546 people) who had been bitten by animals during the studied period, 55.57% were living in rural and 44.43% in urban areas; 79.36% of them were treated by non-completed rabies prophylaxis regimens and 20.64% received completed rabies prophylaxistreatment regimens. The most common affected age group was 10–19-year-old persons; the least was children aged under 4 years. Males were more frequently (73.48%) affected than females (26.52%) (P<0.01). We found that there was a significant inverse correlation between the amount of annual raining and the incidence of animal bites (r=0.5, P=0.01); the incidence of animal bites was increased during the drought years. The increasing number of stray dogs and cats should not be ignored by public health authorities as well as Veterinary Public Health Organizations related to strategic programs of rabies control in the southeast of Iran.

This report is on infestation with Chorioptes bovis of Holstein cattle on a dairy farm included 900 cows in Tabriz. Ten heifers and 25 milking cows under the age of 5 years were infested. Clinical signs consisted of alopecia, crusts, ulcerations and superficial skin fissures. Pruritus and itching were severe in all cases. Lesions were present around the base of the tail, on the neck and below the knee. Skin scrapings were examined and eggs, larvae, nymphs and adult mites were recovered. The infested animals were separated from others and treated three times at weekly intervals with 0.05% solution of sebacil. Signs of improvement were observed after the final treatment.

On June 2005, a respiratory disease was observed in the chickens of a large broiler farm in Kermanshah province, west of Iran. Relatively severe respiratory signs started with sneezing at 27 days of age. The disease lasted up to the end of fattening period and accompanied by increased mortality (13.6%). At postmortem examination, tracheitis, airsacculitis and pneumonia were obvious. Serologic examinations were negative for Mycoplasma gallisepticum and Mycoplasma synoviae. On virologic examinations, virulent infectious bronchitis virus (IBV), avian influenza virus (AIV) and virulent Newcastle disease virus (NDV) could not be isolated. Histopathologic examinations showed no pathognomonic lesion typical for infectious laryngotracheitis. On bacteriologic examinations, Ornithobacterium rhinotracheale (ORT) was isolated from trachea, lungs and air sacs of the affected birds. Based on clinical, post-mortem and laboratory findings, ORT could be probably the primary cause of respiratory disease on this farm.

The purpose of this study was to gain more information on the structure of different layers of renal artery and comparing these structures in post-natal male and female sheep. To do so, right and left renal arteries of 6 adult and 6 newborn animals were dissected; the middle parts of arteries were only collected. After tissue processing using paraffin embedding method, 5–6-mm sections were cut and stained with haematoxylin and eosin, green Masson's trichrome and Verhoeff's elastic fiber methods. Three layers were identified in the wall of artery in both sexes. In tunica media the number of rows of circular smooth muscle cells was 15–25 rows in newborn and 30–40 in adult sheep. External elastic membrane was visible in adult and was structurally thinner than the internal membrane. Tunica adventitia was visible in all samples and collagen fibers and smooth muscles bundle were distinguished. The existence of these muscle bundles in external layer of renal artery was not reported previously in domestic animals and regarded as a new finding in the present study. These muscle bundles were thicker in adult than in newborn animals and probably have a relationship with the function of kidney's vascular system. It was concluded that these bundles may potentiate the tunica media muscle cells to prevent hypertension crisis.

An 8-month-old female thoroughbred foal was presented showing signs of colic. The foal was anxious, exhibiting signs of abdominal pain and distention. The foal had tachycardia (120 beats/min), tachypnea (40 breaths/min). Blood samples obtained for haematologic and serum biochemistry analysis that showed a PCV of 30% and a TPP of 70 g/L. The peritoneal fluid analysis revealed a clear fluid with mild elevation of total protein. The early treatment involved intravenous administration of a balanced electrolyte solution and analgesics. The signs of abdominal pain were progressive and nonresponsive to treatments. Therefore, exploratory laparatomy was elected. During the exploratory laparatomy a faecalith impaction of small colon was detected. The mass was manipulated, macerated and milked toward the rectum and anus. It was finally removed via the anus without enterotomy incision. Midline incision and skin incision were sutured routinely. The foal made an uneventful recovery.

At necropsy of a five-year-old sheep, a pear shaped, lobular yellow-brownish mass measuring about 12x15x20 cm was found to involve the right hepatic lobe. Microscopic examination revealed two trabecular and solid patterns of neoplastic hepatocytes. In solid pattern, there were numerous tumoral giant cells that contain one or more large hyperchromatic bizarre-shaped nuclei scattered among clusters of neoplastic hepatocytes. In addition, mitotic figures, dilated sinusoids and large vascular spaces filled with red blood cells were observed in some sections. Based on gross and histopathologic characteristics, the mass was diagnosed as hepatocellular carcinoma.

An 8-year-old female Japanese Spitz dog was reffered to Shiraz University Veterinary Clinic, with sign of anisocoria. Clinical examinations revealed mydriasis in the right eye. Ocular examination revealed a dilated and unresponsive right pupil to focal illumination. By testing with topical 2% pilocarpine, the tentative diagnosis was parasympathetic denervation of the right iris sphincter muscle-pupillotonia.

Herein, we described the first case of self-inoculation in a veterinarian with bovine Johne's disease (BJD) attenuated vaccine in Iran that required medical attention. A needle-stick injury to the right thumb of a young veterinarian during vaccination of cattle with BJD vaccine resulted in an inflammation that not only failed to resolve but also progressed to a lesion 2.5 cm in diameter. The usual conservative treatment of this wound was not effective. Surgical intervention for debridement of the inflammatory tissue was not performed. For diagnosis of lesion, needle biopsy was prepared from the inflamed tissue mass. Histopathologic examination revealed a tuberculoid granulomatous inflammation without any caseous necrosis. The wound healed by taking rifampin.

Nitrate toxicosis associated with consumption of pigweed red-root (Amaranthus retroflexus) was diagnosed in a small herd of cattle in the suburb of Mashhad, northeastern Iran. The clinical signs were ruminal tympany, incoordination, tachycardia, dyspnea, head pressing, aggressive movements and jugular distension. Seven animals including 3 young calves and 4 cows died of intoxication; other affected cattle were treated by intravenous administration of epinephrine and ascorbic acid. No further mortality was observed after the treatment. One of the treated cows aborted a 6-month-old fetus more than three days after intoxication. Two samples of suspected plants were analysed for nitrate. The nitrate content of those plants was 6.6% and 10.4% in dry matter.