IRANIAN JOURNAL OF VETERINARY RESEARCH (IJVR)
Year:2007 | Volume:8 | Issue:3 (20)|Papers Count:15

Avian intestinal spirochaetosis (AIS) is a condition arising from colonization of the caeca and colon of  irds with anaerobic spirochaetes of the genus Brchyspira. The purpose of the present study was to evaluate PCR amplification from formalin-fixed, paraffin-embedded tissue method for detecting infected laying hens with Brachyspira pilosicoli with the same primers that have been used for detecting the infection in live birds. Over a 4-week period following experimental infection, the faeces of three of the eight inoculated birds became culture-positive. At post-mortem examination, no specific pathological changes were found, and in histological examination of caeca, no forming a “false brush border” was observed, but the spirochaete-form bacteria were present between the intestinal villi. Faecal and swab cultures from caeca of three infected birds became positive and confirmed by PCR amplification of 16S rRNA gene of B. pilosicoli. But this gene was not detected by PCR amplification from fixed caecal tissues of infected birds. This result might be due to low number of bacteria in each section or damage and fragmentation of target DNA.

Milk samples were collected from quarters of 35 cows with subclinical mastitis (California mastitis test [CMT] positive and somatic cell counts [SCC] >500,000 cells/ml in individual quarter foremilk), as well as from 37 healthy controls. Compared to the levels observed in milk from healthy quarters, milk from quarters with subclinical mastitis showed elevated sodium (91.97 vs 52.93 mg/dl), chloride (>0.14 vs <0.14 g/dl), pH (6.69 vs 6.59), albumin (5.62 vs 2.65 g/dl), lactate dehydrogenase (LDH) activity (1524.04 vs 485.94 IU/L) and immunoglobulins (26.86% vs 7.43%). In contrast, decreased values were found for calcium (90.45 vs 126.29 mg/dl), inorganic phosphorous (24.40 vs 30.59 mg/dl), potassium (151.56 vs 167.74 mg/dl), a- lactalbumin (22.25% vs 28.72%) and b-lactoglobulin (34.21% vs 57.08%). No changes were seen in blood serum LDH activity. Furthermore, an increase in positive response to CMT was found to be accompanied by an almost proportionate increase in immunoglobulin values to 48.20% and decrease of a-lactalbumin levels in milk serum (P<0.01). These changes in pH, mineral concentrations, LDH activity and protein fractions in milk of quarters show the presence of tissue damage provoked by SCM. Thus, these parameters can be used in the diagnosis of mastitis.

The pharmacokinetics of cefpirome was investigated in buffalo calves following its single intramuscular (IM) administration (10 mg). The peak plasma concentration of cefpirome at 30 min was 9.0 ± 0.5 mg.ml-1, which declined to 0.2 ± 0.1 mg.ml-1 at 24 hrs. The absorption half-life (t1/2Ka) and elimination half-life (t1/2 b) were 0.19 ± 0.03 hr and 2.39 ± 0.05 hr, respectively. The area under the plasma concentration-time curve (AUC), area under the first moment curve (AUMC), apparent volume of distribution (Vdarea), total body clearance (ClB), mean residence time (MRT) and total duration of therapeutic effect (td) were 28.7 ± 1.9 mg.ml-1.hr, 107.7 ± 6.7   g.ml-1.hr2, 0.42 ± 0.01 L.kg-1, 0.12 ± 0.003 L.kg-1.hr-1, 3.76 ± 0.04 hr and 12.7 ± 0.3 hr, respectively. The systemic bioavailability (F) after IM administration of cefpirome in calves was 35.3 ± 3.1%. To maintain a minimum therapeutic concentration of 0.25 mg.ml-1, a satisfactory dosage regimen of cefpirome in buffalo calves was 3.46 mg.kg-1 followed by 3.36 mg.kg-1 at 12-hour intervals. Cefpirome was bound to the plasma proteins of buffalo calves in vitro to the extent of 30.7 ± 1.9%.

The objective of this study was to evaluate three methods of estrous synchronization, viz. controlled internal drug releasing device (CIDR), intravaginal sponges impregnated with fluogestone acetate (FGA), and cloprostenol (Estrumate; an analogue of prostaglandin F2a) in Nadooshani goats of Yazd province, Iran. The estrous synchronized does (n = 30 to 33 per treatment), after heat detection, were artificially inseminated (once) with diluted semen of fertile bucks. Pregnancy was determined by measuring blood serum progesterone levels on day 21 after insemination, followed by ultrasonography at mid-gestation. No significant difference was observed for the interval between the end of the synchronization protocol and the standing heat amongst treatments (range: 23 to 35 hrs). There was no significant difference in the interval between the time of standing heat and insemination among treatments (range: 15 to 27 hrs). Blood serum progesterone levels (overall mean: 4.80 ± 0.41 ng/ml; SEM), litter size (overall mean: 1.32 ± 0.05; SEM), non-return rate to estrus and the kidding rate were not significantly affected by the synchronization methods. Serum progesterone levels were significantly lower (P<0.01) in does that returned to estrus after artificial insemination (AI). Prolificacy and fecundity were not significantly affected by the synchronization methods; however, cloprostenol method was found to be more convenient and economical under the conditions of this experiment.

Tenderness is the single most important factor influencing consumer acceptance of meat. The calpain proteolytic system is known to be responsible for the post-mortem tenderization of meat. The purpose of this study was to determine and compare the tensile strength and total calpain activities in different muscles of camel, cattle, sheep and goat. In camels, the effect of age and sex of animal was also studied. Twenty-four animals (camel, cattle, sheep and goat) were sampled randomly after slaughtering. Samples from biceps femoris, longissimus dorsi and triceps brachii and heart were obtained from each animal. The tensile strength was calculated using an Instron Universal testing machine. After homogenization of samples in 0.1 M NaCl and centrifugation, total calpain activity was determined by fluorometric method. Despite significant differences in tensile strength, no significant difference (P>0.05) was observed among calpain activities of different muscles in each species. Inter-species differences however, were significant (P<0.05). In all muscles, the highest calpain activity was found in camel (3.08–5.36 RFU/mg protein) followed by cattle (3.65–4.43 RFU/mg protein), sheep (1.17–2.82 RFU/mg protein) and goat (1.24–2.23 RFU/mg protein). No significant differences were observed between camel and cattle and also between sheep and goat in tensile strength (P>0.05). In camel, adult animals had higher calpain activity and tensile strength than youngs; sex had no significant effects. Correlation coefficients of calpain activity and tensile strength were negative and not significant in all species. In conclusion, meats from different species might show different degrees of tenderness, partly due to the difference in their calpain activity.

The specificity of gentamicin for vitamin E deficiency-associated oxidative stresses in the renal proximal convoluted tubules is apparently related to its ability to increasingly facilitate generation of radical species in mitochondria. To determine the ways in which vitamin E manage the currently processes, we conducted a prospective study aimed to investigate the tubular preserving effect of vitamin E, pre-treatment and cotreatment, in nephrotoxicity with gentamicin-treated Sprague-Dawley rats. 35 healthy rats were ascribed 1–5 trials to receive once daily intramuscular injections of either gentamicin (80 mg/kg/body Wt) (GN), normal saline (NS), vitamin E (250 mg/kg/body Wt) (VE), vitamin E (250 mg/kg/body Wt) plus gentamicin (80 mg/kg/body Wt) simultaneously (CGE), or vitamin E alone (250 mg/kg/body Wt) 3 days before coadministration with gentamicin (80 mg/kg/body Wt) (PGE), for 10 dys. Gentamicin alone caused a decrease in glomerular filtration rate-associated coefficient of the creatinine clearance, increase in blood content of BUN as well as a decrease in tubular function evident by recognised depression of ATPase activity, increases in lipid peroxidation and subsequently MDA activity. The histopathologic studies revealed acute tubular necrosis with tubular cast formation triggered by gentamicin treatment over 10 days of experiment and change in size and pattern of tubules. Further biochemical studies showed tubular preserving effect of vitamin E pre-administration including slow down in rising enzyme activity (MDA) and mild to moderate BUN with recovery in creatinine clearance and holding ATPase activity up to 50% on comparison with the control and vitamin E alone-treated rats. Significant tubular resistance against gentamicin proximal tubular lesions on the suppressed activity of lipid oxidation induced by vitamin E pre-treatment with normal size during microscopic inspections lead us to conclude protective role of vitamin E is probably attributed to tubular prevention, whereas hyperemia prepared by vitamin is only a consequent.

In this report, b-tubulin gene polymorphism was investigated in Haemonchus contortus populations isolated from sheep flocks in different regions of Khouzestan province, southwestern Iran. The samples were chosen on the basis of regional variation in benzimidazole treatment background of sheep flocks. Our objective was to study the relationship between treatment background and b-tubulin gene polymorphism of H. contortus isolated from the selected regions. H. contortus isolated from Shooshtar revealed reduction in b- tubulin gene polymorphism restriction fragment length polymorphism (RFLP) in respect to other isolates indicating that benzimidazole-resistant isolates of H. contortus developed in some sheep flock of Shooshtar region.

The calcium status of lactating, non-lactating, and male sheep on farm in southwestern Punjab, Pakistan was studied. Pasture and animal were sampled at the end of the first month of summer and winter. All samplings were carried out fortnightly. A mineral supplement was available to all animals throughout the year. Plasma calcium in all animals was not affected by the physiologic state and gender as it was severely deficient in all classes of animals. The calcium concentrations of forage and plasma in all classes of sheep, and milk in lactating sheep were affected by the season (P<0.001). In the lactating sheep, the marginal deficient levels of calcium for requirement (1200-2600 mg/kg) in summer and moderate deficiency (1200- 2600 mg/kg) for sheep requirement during winter were found. In non-lactating sheep, plasma calcium was moderately deficient during winter and marginally deficient in summer. In male sheep, plasma calcium level in summer was marginally deficient while plasma calcium during winter was moderately deficient. Soil and forage calcium concentrations were found within the same range during both seasons and showed a positive association between them (P<0.001). Based on these analyses, it was concluded that the calcium status of grazing sheep in this specific region needs supplementation with specifically tailored mixture to achieve the maximum potential of grazing sheep in this ranch.

Testosterone enanthate (TE) is used by many athletes as a muscle builder. Previous studies showed that high concentration of the drug in plasma may affect the natural function of endocrine glands, specially the secretion of the adrenocortical hormones. The objective of the present study was to examine the effects of high concentration of TE on histometrical structure of adrenal cortex in male rats. 120 Charles River rats were equally divided into 5 groups of gonadectomized rats receiving (G+TE), non-gonadectomized rats receiving TE (Sh+TE), gonadectomized rats receiving vehicle (G+S), non-gonadectomized rats receiving vehicle (Sh+S), and the control rats which were neither operated nor received vehicle or drug (CO). The animals were given either 0.5 ml normal saline as vehicle or 5 mg/100 g body weight TE in equal volume of normal saline. Nine weeks after receiving drug or vehicle, serum levels of testosterone were determined, and histometrical studies were performed on tissues from adrenal glands using haematoxylin and eosin staining. There was a significant increase in serum levels of testosterone in G+TE group compared to the CO one. Moreover, the diameters of the nuclei and cells from zona glomerulosa, zona fasciculate and zona reticularis showed a significant increase compared to the CO group. The results indicated that TE has an increasing effect on the nuclei and cell size of the adrenal cortex.

Streptococcus agalactiae, S. dysgalactiae and S. uberis are Gram-positive bacterial pathogens that affect cows in dairy herds. These are considered as the major causes of economic losses of dairy producers without a control program. To reveal the role of these agents in inducing subclinical mastitis in dairy cattle in Ahvaz, 100 CMT-positive milk samples and 20 CMT-negative milk samples were collected and examined by polymerase chain reaction (PCR). The results were compared with the conventional bacterial culture. Based on the PCR results, S. agalactiae, S. dysgalactiae and S. uberis were causative agents in 20, 12.5 and 0.83% of samples, respectively. There was not any culture-positive samples being negative in PCR, but there were 10 PCR positives being negative in culture method. Based on McNemar test, there was 91.6% agreement between PCR and culture methods for the diagnosis of streptococcal mastitis. There were 14 and 7 CMTnegative samples, being positive by PCR and culture methods, respectively. The results of this study showed that subclinical infections from these bacteria are prevalent in dairy cattle of Ahvaz and regular testing and control programs should be planned to control the infection. CMT has not sufficient sensitivity for detection of subclinical mastitis due to these agents.

To study changes in concentrations of some biochemical factors of amniotic fluid, 115 normal goat uteri at different stages of pregnancy were collected from slaughterhouse. After expelling of each fetus accompanied by fetal membranes, 10 ml amniotic fluid was taken from amniotic sac for biochemical analysis. Then approximate ages of fetuses were calculated by using age estimation formula. At five stages of five months of pregnancy, the following results were obtained, respectively: sodium concentrations were 123.3, 125, 115.9, 122 and 120.8 mmol/L; potassium, 6.2, 5.2, 5.8, 4.9 and 5.6 mmol/L; chloride, 101.4, 115.1, 117.3, 106.6 and 94.9 mmol/L; glucose, 7.1, 11.5, 8.8, 4.9 and 3.6 mg/dl; urea, 43.7, 69.3, 84.8, 117 and 91.7 mg/dl; uric acid, 0.4, 0.1, 0.1, 0.3 and 0.7 mg/dl; creatinine, 1.5, 0.6, 0.6, 5 and 5.9 mg/dl and total protein with the highest value of 54.2 mg/dl at the first month of pregnancy and the lowest value of 26.6 mg/dl at the second month.

Mammary secretions of 913 quarters from 229 pregnant Holstein heifers were obtained aseptically to determine the prevalence of coagulase-negative Staphylococci isolated during periparturient period. Quarter samples were collected 14 to 10 days before expected parturition. Analysis of culture data indicated that 78.5% (717/913) of samples were negative, 20.5% (187/913) contained coagulase-negative Staphylococci, 0.33% coagulase-positive Staphylococci, 0.33% E. coli, 0.22% Arcanobacterium pyogenes and 0.11% environmental Streptococci spp. A total of 187 isolates of coagulase-negative Staphylococci were tested in vitro for susceptibility to 8 antimicrobial agents. Susceptibility was detected in 180 (96.3%), 187 (100%), 163 (87.2%), 168 (89.8%), 183 (97.9%), 187 (100%), 174 (93%) and 164 (87.7%) isolates for oxytetracycline, gentamicin, streptomycin, tylosin, cloxacillin, enrofluxacin, trimethoprim+ sulphamethoxazole and penicillin G, respectively. More than 93.8% of the isolates were susceptible to all antimicrobial agents tested. In conclusion, results of this study suggest that coagulase-negative Staphylococci spp. is the most prevalent microorganism isolated from intramammary secretions in pregnant heifers which is susceptible to common antibiotics in vitro.

This study was conducted to determine the prevalence of Salmonellae contamination of chicken carcasses in slaughterhouses in central Iran (Yazd province). 435 samples were obtained from liver, breast-before and after chilling-and bacteriological and serological examinations were done. The results showed that the rate of contamination of liver, breast meat-before and after chiller-were 8.1, 18.48 and 34.45%, respectively. Serological tests showed that S. typhimurium was the main contaminant of the samples (52.2%). Other isolated serotypes were S. newport (15.6%), S. enteritidis (12.2%), S. havana (8.9%), S. dublin (5.6%) and S. paratyphi-B (5.6%). Bacteriological examinations on water of chiller indicated that 33.3% of chill water samples were contaminated with S. typhimurium, 8.3% with S. dublin and 8.3% with S. paratyphi-B.

A seven-year-old stallion with diversion of urinary pass to the thigh due to a urethral fistula caused by gunshot perineal injury was presented to the Urmia University, Veterinary Teaching Hospital. No signs of urinary obstruction or renal failure were observed. Because of inaccessible location of the injured urethra, through a perineal urethrotomy incision, a urinary catheter was effectively advanced to repel the obstruction into the bladder. Retrograde urethral catheterization was adopted for 5 days to assist mucosal healing. Healing was uneventful and no complications were observed during one month postoperative.

Tumours of odontogenic origin have been reported in various domestic animals. Ameloblastic fibroodontoma is a rare tumour derived from odontogenic epithelium and pulpal mesenchyme. Plain and formalised sections from masses on the front of the cranial aspect of the jaw and the end of the tongue of a castrated beef cattle from an abattoir was submitted to Mt Pleasant laboratories, Launceston, Australia. Histologically long cords and discrete islands of odontogenic epithelium in a background of loose mesenchymal tissue reminiscent of dental pulp were observed. Based on microscopi c and macroscopic features, the tumour was diagnosed as ameloblastic fibro-odontoma.