Relationship between hepcidin and oxidant/antioxidant status in calves with suspected neonatal septicemia.

AIM: This study has been conducted for the purpose of determining serum hepcidin, total antioxidant status (TAS), total oxidant status (TOS), and Fe levels in calves with suspected neonatal septicemia before and after treatment and the clinical significance of hepcidin in calves with suspected neonatal septicemia. MATERIALS AND METHODS: The study material consisted of 15 calves of different ages and sexes brought to the Training, Research and Application Center at the Kafkas University Faculty of Veterinary Medicine with suspected neonatal septicemia. 8.5 mL of blood was drawn from the jugular vein of each animal into coagulant tubes before and after treatment for one-off biochemical analyses and centrifuged. After this, the serum was separated. Hepcidin, TAS, TOS, and Fe levels in the serum were measured. RESULTS: While pre-treatment hepcidin levels were 58.42±3.46 ng/mL, post-treatment levels were 46.87±2.98 ng/mL (p<0.05). Pre-treatment Fe levels were 60.13±7.27 µg/dl, while post-treatment levels were 83.1±8.09 µg/dl (p<0.05). The changes in the TAS and TOS levels were also found to be statistically significant. CONCLUSION: In light of the fact that hepcidin plays a role function in the regulation of Fe as well as the fact that Fe is a significant nutritional source for many microorganisms, it was concluded that hepcidin may play a significant role in nutritional immunity and the pathogenesis of diseases.

Effects of reduced glutathione on nitric oxide level, total antioxidant and oxidant capacity and adenosine deaminase activity.

The aim of this study was to determine the effect of exogenous GSH, an important antioxidant containing thiol group, on total antioxidant capacity (TAC) and total oxidant capacity (TOC), adenosine deaminase (ADA), a significant indicator of cellular immunity, and nitric oxide (NO) concentrations in rabbits. Sixteen healthy New Zealand rabbits were divided into 2 groups as control and GSH-treated group. Animals in control group received single intraperitoneal (ip) administration of 0.9% saline. Rabbits in GSH-treated group received reduced L-glutathione (10 mg/kg) (ip). Blood samples were taken from the marginal ear vein 0, 3, 6 and 12 hours after injection. Plasma TAC and NO levels were not statistically different between control and GSH group at 0 and 12 hours. Plasma TAC level was found to be significantly higher (p < 0.05) while NO level was found to be significantly lower (p < 0.05) in GSH treated group when compared to control group at 3 and 6 hours. Plasma TOC and ADA activity were not statistically different between control and GSH group during experiment. In conclusion, exogenous GSH resulted in an alteration of TAC and NO but not TOC and ADA, so exogenous GSH may be a valuable enhancer of the antioxidant system.

Investigation of oral selegiline and rasagiline administration on QT interval in conscious rabbits.

Rasagiline (RSG) and selegiline (SEL) are potent selective monoamine oxidase-B inhibitors and used in the treatment of Parkinson's disease. Selegiline is metabolized in vivo to I-methamphetamine and I-amphetamine which effect cardiovascular system. Therefore, the aim of this study was to evaluate and to compare the effects of long-term use of these drugs on QT interval in conscious rabbits. The study involved 17 New Zealand rabbits of both sexes, aged between 7 and 14 months. Control group (CG, n = 6) was orally given isotonic saline solution at dose of 0.5 cc/per rabbit. The SEL group (SG, n = 6) received 5 mg/per rabbit SEL orally twice daily (09:00 am and 09:00 pm) for 14 days. The RSG group (RG, n = 5) was orally given of RSG at 1 mg/per rabbit daily for 14 days. Electrocardiographic records were taken before the experiment (baseline) and at 1st, 7th, and 14th days of experiment by direct writing electrocardiograph for two groups. Heart rate (HR), QT and QTc values were determined from ECG records. HR did not significantly differ in both treatment groups through the experimental period when compared to baseline values. The significant prolongation of QT and QTc values were observed at 7th, and 14th day (p < 0.01) in SG and 1st day of experiment in RG (p < 0.05) as compared to baseline values. In conclusion, the results obtained suggest a statistically significant effect of SEL on QTc prolongation when compared to RAS. QTc prolongations should be taken into account in Parkinson's disease where autonomic system is involved.

Effects of therapeutic doses of Pregabalin on QTc interval in conscious rabbits.

Pregabalin (PRG) is a new antiepileptic drug that has been used as supportive therapy for partial seizures in patients. Although many neuro-psychiatric and non-cardiac drugs are known to prolong ventricular repolarization as manifested by QTc prolongation on ECG of which provokes torsades de pointes, there is limited data available regarding the characteristics of QT interval in conscious laboratory animals after PRG administration. For that purpose, effects of different therapeutic doses of oral PRG administration on Heart Rate (HR), QT and QTc values in rabbits were evaluated at a predefined time interval in this research. The study involved 28 New Zealand rabbits of both sexes, aged between 8 and 12 months. Animals were divided into four equal groups. Rabbits in control group (CG) received saline 0.5 ml/per animal orally. Group I, II and III were orally given single dose of PRG at 1.25 mg/kg, 2.5 mg/kg and 5 mg/kg, respectively. ECG records were taken before experiment (baseline) and at 1st, 2nd, 4th, and 6th hour (h) of experiment by direct writing electrocardiograph. HR, QT and QTc values were determined from ECG records. Heart rates increased in all groups when compared to baseline values. The increases were evident at 4th h in group II (p < 0.001), at 2nd h (p < 0.05) and 4th h (p < 0.001) in group III compared with CG. After application of PRG, QTc began to prolong at 1st h through the 4th of experiment and then turned to baseline values at 6th h of the experiment. The QTc values obtained at 2nd h in Group II and III (p < 0.05) and 4th h (p < 0.001) of application in group III were significantly different from CG. Changes obtained in HR, QT and QTc values in PRG treated rabbits were time and dose dependent (p < 0.001). Increase in HR and QTc prolongation determined in PRG given rabbits may implied that clinicians should take care of these changes when using this drug and further studies are required to fully understand the mechanism involved.

Use of cardiac troponin kits for the qualitative determination of myocardial cell damage due to traumatic reticuloperitonitis in cattle.

This study was designed to investigate whether kits to measure circulating cardiac troponin-I (cTn-I) and cardiac troponin-T (cTn-T) can be used to determine myocardial cell damage in cattle with traumatic reticuloperitonitis (trp). Twenty cattle with trp were compared with 10 clinically healthy cattle. cTn-I and cTn-T were determined qualitatively and cTn-I was determined quantitatively; biochemical analyses were also performed on both groups. The mean serum concentrations of total protein, globulin, glucose and calcium, and the mean activities of creatine kinase mb, aspartate aminotransferase, lactate dehydrogenase and gamma-glutamyl transferase were higher in the cattle with trp than in the control group. The cTn-I and cTn-T kits both gave positive results in three of the cattle with trp and the quantitative measurement of cTn-I was positive in 11 of the trp cases. Both tests were negative in the healthy cattle.

Serum sialic acid and oxidative stress parameters changes in cattle with leptospirosis.

This study was designed to disclose some indicators of oxidative stress and inflammation in natural cases of bovine leptospirosis. For this purpose, 12 bulls exhibiting clinical signs of leptospirosis and 10 healthy bulls were used. Animals were subjected to thorough clinical examination and the clinical signs were recorded. All animals were blood sampled in order to determine serum total sialic acid (TSA), lipid bound sialic acid (LBSA), malondialdehyde (MDA), reduced glutathione (GSH), nitric oxide (NO), uric acid (UA), total protein (TP), albumin and glucose. Urine samples were collected from each animal and examined under dark-field microscope to observe spirochetes. Diseased animals exhibited clinical signs suggesting leptospirosis and the diagnosis was supported by positive dark-field microscope examination. Mean TSA (mmol/L), LBSA (mmol/L), TP (g/dl), albumin (g/dl), glucose (mg/dl), MDA (micromol/L), GSH (mg/dl), NO (nmol/ml), and UA (mg/L) levels were 1.63 +/- 0.02, 0.40 +/- 0.10, 7.18 +/- 0.24, 3.23 +/- 0.5, 64.96 +/- 1.88, 5.71 +/- 0.11, 78.68 +/- 0.72, 7.94 +/- 0.34, and 8.75 +/- 0.41 in healthy bulls, and 2.50 +/- 0.05, 0.70 +/- 0.2, 9.27 +/- 0.17, 2.55 +/- 0.62, 107.93 +/- 2.52, 8.82 +/- 0.14, 47.85 +/- 1.85, 14.57 +/- 0.63 and 15.85 +/- 0.80 in leptospirosis cases, respectively. The differences between the two groups were statistically significant (P < 0.001). Increased TSA, LBSA, MDA, NO, UA, TP, glucose and decreased GSH and albumin concentrations were suggestive of inflammation and oxidative stress in diseased bulls. The results obtained may suggest that oxidative damage along with other mechanisms might have taken part in the pathogenesis of bovine leptospirosis and further detailed studies are needed to fully understand the mechanism(s) of the disease.

QT interval prolongation and decreased heart rates after intravenous bolus oxytocin injection in male and female conscious rabbits.

The aim of this study was to evaluate changes in heart rate (HR), QT and RR intervals and corrected QT (QTc) values in conscious male and female New Zealand rabbits which intravenously received oxytocin (OXT) at different dosages. Animals were divided into 6 equal groups: group I (n = 6 male, received 0.75 U OXT per animal); group II (n = 6 male, received 1.5 U OXT per animal); group III (n = 6 male, received 3 U OXT per animal); group IV (n = 6 female, received 0.75 U OXT per animal); group V (n = 6 female, received 1.5 U OXT per animal); group VI (n = 6 female, received 3 U OXT per animal). ECG recording were taken from all animals before injection and then at 2, 4, 6, 8, 10, 15 and 20 min of OXT administration. QT and RR intervals obtained at 2 min of OXT administration were significantly prolonged in all groups (p < 0.05) with one exception that is the 1.5 U OXT injected female group where only QT interval did not change. The prolongation of QT and RR intervals persisted for 20 min in 1.5 U OXT injected male group while only QT interval prolongation was obvious for 20 min in 3 U OXT injected female group as for the other groups the prolonged interval were observed for 8-10 min and then returned to baseline values. Generally, a significant prolongation of QTc was noticed in both male and female rabbits at the 2 and 4 min in all groups and bradycardia was noticed at 2 min of OXT administration in all groups. Heart beats returned to normal values in all groups after 8 min of OXT administration. The change of HR, RR, QT and QTc was gender- but not dose-dependent (p < 0.001). The male rabbits were more sensitive to OXT effect then female rabbits. In conclusion, OXT used in therapeutic dosages decreased heart rate and prolonged QT and QTc intervals. Although cardiovascular effect of OXT are of short duration, its use in patient with risk factors for malignant arrhythmias requires more attention.

The effects of levamisole poisoning on the haematological and biochemical parameters in dogs.

This study was designed to evaluate possible organ and system disorders associated with experimentally induced levamisole poisoning in dogs. For this purpose, twelve clinically healthy dogs of different ages, sexes and breeds were used. They were divided into two equal groups (Group A and Group B) and given levamisole orally at a dose of 25 mg/kg of body weight daily for three days. The dogs in Group B were also injected with atropin sulphate (0.04 mg/kg of body weight) subcutaneously (sc) 1 hour after each administration of levamisole. Routine clinical examinations were made and some haematological, biochemical and blood gas parameters were established at various times after administration of levamisole. The dogs in Group A developed severe neurological signs, gastric haemorrhage, bloody vomiting, colic, anaemia and four dogs died. In Group B these signs were mild and only one dog died. Levamisole poisoning was characterised by a significant reduction in the total number of red blood cells (RBCs), concentration of haemoglobin (Hb) and packed cell volume (PCV), and by anaemia. Peripheral blood pH, actual bicarbonate of plasma (HCO3), actual base excess (BE), partial pressure of oxygen (pO2) and saturated oxygen (O2SAT) increased in both groups of animals and these dogs developed metabolic alkalosis 48 hours after the first administration of levamisole. The results of the study also show that levamisole poisoning in dogs causes a significant increase in the activity of serum alanine aminotransferase (ALT) and of alkaline phosphatase (AP) and in the concentration of urea in both Group A and Group B. In the study, atropin sulphate reduced the severity of the clinical signs and the number of deaths, but it was not alone sufficient to remedy levamisole poisoning in dogs.

Optimization of a culture technique for the isolation of Listeria monocytogenes from faecal samples.

A culture technique employing cold enrichment at 4 degrees C followed by selective enrichment and plating at higher temperatures (30 degrees C) was used to isolate Listeria monocytogenes from faecal samples. The samples were held at 4 degrees C for 15 weeks and cultured weekly to assess the sensitivity of the culture after cold storage for different lengths of time. No media, Listeria selective enrichment broth (LSEB), nutrient broth (NB) and saline were used as cold storage medium. Cold storage increased the frequency of Listeria positive samples. The sensitivity of the culture for Listeria spp. and L. monocytogenes was 72 and 94%, and 56 and 61% after third and seventh week of cold storage, respectively. When the results of third and seventh week of cold storage were combined, the sensitivity was 100% for Listeria spp. and 94% for L. monocytogenes. LSEB and NB as storage medium increased Listeria positive samples after the first week of cold storage but did not maintain the increase thereafter while saline had an adverse effect on the growth of the bacteria. However, samples held in no media in a pilot study involving monthly sampling of a herd revealed better results. Detection limit of the culture media was also investigated. The lowest concentration detected by culture media was 3.17 organisms/ml. This was seven organisms/g for known Listeria positive sample. The faecal samples spiked with 10-fold dilutions of L. monocytogenes and held at 4 degrees C revealed that the sample spiked with 3.17 x 10-1 cfu/ml organisms resulted in growth after the second week of cold storage. The results suggest that the culture technique employing cold enrichment followed by selective enrichment and plating is more sensitive, the storage of faecal samples in no media when compared with the samples in storage medium, LSEB, NB and saline, during cold enrichment is a better application and culture of faeces, immediately after collection, at third and seventh week of cold enrichment produce more satisfactory results.

Discrimination of Arcobacter butzleri isolates by polymerase chain reaction-mediated DNA fingerprinting.

AIMS: The objective of this study was to subtype Arcobacter butzleri isolates using RAPD-PCR. METHODS AND RESULTS: Thirty-five A. butzleri isolates obtained from chicken carcasses were examined. PCR-mediated DNA fingerprinting technique with primers of the variable sequence motifs was used to detect polymorphism within the isolates. Eleven distinct DNA profiles were obtained as follows: Of the 35 strains, 10 as profile 4; seven as profile 1; five as profile 3; three as profiles 2 and 9; two as profile 10; one as profiles 5, 6, 7, 8 and 11. CONCLUSIONS: Chicken carcasses sold in markets were found to be contaminated with several different strains of A. butzleri. RAPD-PCR technique was found to be a useful technique for distinguishing A. butzleri isolates. SIGNIFICANCE AND IMPACT OF THE STUDY: The presence of several different A. butzleri strains on chicken carcasses may indicate multiple sources of contamination. The epidemiological role of A. butzleri in human and animal diseases should be investigated further.

Prevalence, incidence, signs and treatment of clinical listeriosis in dairy cattle in England.

The prevalence, incidence and clinical signs of listeriosis in dairy cattle in England were investigated by means of a postal questionnaire survey of 1500 dairy farmers. The response rate was 64.1 per cent. Overall the farm prevalence of listeriosis was 11.7 per cent, 9.3 per cent for milking cows, 5.0 per cent for replacement heifers and 1.4 per cent for dairy calves. The within-herd incidence rate per thousand animal-years was 51.4 for all cases, 39.7 for milking cows, 86.6 for replacement heifers and 73.7 for dairy calves. Most cases of clinical listeriosis were reported between December and May, and the most common signs were silage eye, followed by nervous signs. The results of the questionnaire were validated internally by re-estimating the farm prevalence by including only those cases diagnosed by a veterinarian or veterinary investigation centre; the prevalence did not change significantly. The proportion of cases which were culled or died of encephalitic listeriosis was compared with the proportion diagnosed during statutory BSE reporting. The fact that the two proportions were similar provided external validation for the results of the questionnaire.

Prevalence, incidence and geographical distribution of Johne's disease in cattle in England and the Welsh borders.

The prevalence, incidence and geographical distribution of clinical Johne's disease in dairy cattle in England and the border regions of Wales were determined by a postal survey of 3772 dairy farmers. The study area was divided into three regions; south, central and north. The response rate was 78.3 per cent. The proportion of farms that reported 'ever' having the disease was 17.4 per cent. For the 10 years between 1985 and 1994 it was 4.9 per cent, and only 1.5 and 1.3 per cent in 1993 and 1994 respectively. The highest prevalence figures were always in the south. The incidence rate of clinical disease was 3.0/10,000 cow-years in both years in all herds and 16.7 and 22.8/1000 cow-years in infected herds in 1993 and 1994 respectively. An estimate of the criterion validity of diagnosis by farmers was obtained by comparing the reporting of the clinical signs with positive veterinary or veterinary investigation centre diagnoses. The proportion of farmers reporting one or other of the correct clinical signs was 95.3 per cent, and 70.6 per cent reported both correct signs (diarrhoea and weight loss).

Relationships between the presence of Johne's disease and farm and management factors in dairy cattle in England.

The data collected by a postal questionnaire sent to 3772 randomly selected dairy farmers in England and the border regions in Wales were used to estimate the relationships between the presence of clinical Johne's disease and farm and management factors associated with that disease. Two binary outcomes (case reported in 1993, case reported in 1994) and 27 predictor variables were considered. Only two variables were consistently and significantly associated with clinical disease in multivariable analysis. Farms on which Channel Island breeds were predominant were associated with an increased risk of reporting disease (odds ratios (ORs) ranged from 10.9 to 12.9). The presence of farmed deer on the farm also increased the risk of reporting disease (ORs ranged from 15.2 to 209.3). There were other significant but inconsistent associations involving the source of replacements, age of first-offering hay, type of concentrate feed to calves, and calving in individual pens when the cows were at grass. Since Johne's disease is predominantly subclinical, these contributing factors may play important roles in switching subclinical infection to overt disease.