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Avian mycobacteriosis in domestic chickens from selected agro-climatic regions in Ethiopia
2003
Tadesse, S. | Woldemeskel, M. | Molla, B. | Tibbo, Markos | Kidane, D. | Medhin, G. | Britton, S.
Domestic poultry are important natural hosts of Mycobacterium avium (MAC), especially in the traditional poultry management system in the tropics. Qualitative and quantitative studies on a total of 95 chickens from three agro-climatic areas in Ethiopia were examined for avian mycobacteriosis through postmortem examinations and tissue staining (haematoxylin & eosin and acid-fast staining). The mycobacteria species were isolated and identified by using mycobacteriologic culture and experimental infection for virulence assessment. Five of the 95 examined chickens (5.3%) had gross tuberculous lesions in different visceral organs. On histopathologic examination, the lesions showed granuloma with typical Langhan’s giant cells in which acid-fast bacilli were shown by acid-fast stain. The culture on pyruvate-enriched Lowenstein-Jensen slants revealed growth of colonies on samples from 6 (6.3%) of the 95 chickens. Experimental infection with the strains from culture resulted in death of 10 (83.3%) of 12 inoculated chickens 56 to 110 days after inoculation, indicating that the isolates may be virulent strains of MAC. On postmortem examination, the experimentally infected chickens showed similar tuberculous lesions to natural infection that was confined at the site of injection, on the liver, spleen and (in two subjects) small intestine. The inoculated organisms were recovered from the respective organs. Therefore, this study showed that a virulent strain of MAC infects domestic chicken in Ethiopia.
Afficher plus [+] Moins [-]A cross-sectional study of bovine tuberculosis in selected dairy farms in Ethiopia
2003
Ameni, G. | Bonnet, P. | Tibbo, Markos
A cross-sectional study to determine individual animal prevalence of bovine tuberculosis (BTB) was conducted on 1171 dairy cattle in 12 randomly selected dairy farms in Ethiopia between January 1999 and May 2001 using comparative intradermal tuberculin (CIT) test and bacteriologic study through milk culturing. An overall individual animal prevalence of 46.8% (548 of 1171 animals) and a herd prevalence of 91.7% (11 of 12 farms) were recorded in 12 dairy farms by the CIT test. There were significant (P <0.0001) differences in individual prevalence between farms and breeds (pure Holstein and their crosses with Zebu). There was positive correlation (r = 0.41) between herd size and prevalence of bovine tuberculosis. Furthermore, a negative linear association (R2 = 0.24) was found between mean score of management of the farm and prevalence, indicating that the prevalence of bovine tuberculosis could be improved by sanitary measures. Breed and management affected the prevalence of BTB (R2 = 0.30) as confounding variables. Mycobacterium bovis was isolated from the milk of 13.3% (4 of 30) reactor cows. The widespread occurrence of BTB in the study farms and isolation of M. bovis from the milk of reactor cows signify its economic importance and potential risk to public health. Generalization and improved use of milk pasteurization within all dairy subsectors is recommended, and this would affect the competitiveness of the dairy sector in Ethiopia.
Afficher plus [+] Moins [-]Bovine Tuberculosis: Prevalence and risk factor assessment in cattle and cattle owners in Wuchale-Jida District, central Ethiopia
2003
Ameni, G. | Amenu, K. | Tibbo, Markos
A cross-sectional study was conducted between December 2001 and April 2002 on 94 households and 763 (188 indigenous and 575 crossbred) cattle to determine the prevalence of bovine tuberculosis (BTB) and assess its public health implications in smallholder farms in Wuchale-Jida District, Central Ethiopia. Cluster sampling, single intradermal tuberculin (SIDT) and comparative intradermal tuberculin (CIDT) tests, a questionnaire, and mycobacteriology were used. Based on the CIDT test, herd and individual animal prevalences of BTB were 42.6% and 7.9%, respectively. The individual animal prevalence was significantly affected by herd size (P<0.01), age (P<0.0001) and body condition (P<0.05). Among the interviewed households, 24.5% (23 of 94) had experienced at least one human tuberculosis case in the family. Of these families, 43.5% (10 of 23) had reactor cattle. Nevertheless, no statistically significant association (P>0.05) was observed between reactor cattle and human tuberculosis cases in households. The habit of milk and meat consumption was affected by occupation (P<0.0001) and location of household residence (P<0.001). Although the level of education influenced the habit of milk consumption (P<0.05), it did not impact the habit of meat consumption (P>0.05). Less than half (38.3%; 36 of 94) of the respondents knew about BTB, and only 30.8% (29/94) of the respondents were conscious of its transmission from cattle to humans. Secondary data analysis from Muka-Turri clinic indicated that 85.6% of the human tuberculosis cases were from rural parts of the district. Although the BTB prevalence seems low, its potential risk to public health was important based on food consumption, poor sanitary measures, and the lack of understanding about its zoonosis.
Afficher plus [+] Moins [-]Use of the impulse oscillometry system for testing pulmonary function during methacholine bronchoprovocation in horses.
2003
Van Erck, Emmanuelle | Votion, Dominique | Kirschvink, Nathalie | Art, Tatiana | Lekeux, Pierre
peer reviewed | OBJECTIVE: To compare sensitivity of the impulse oscillometry system (IOS) with that of the conventional reference technique (CRT; ie, esophageal balloon method) for pulmonary function testing in horses. ANIMALS: 10 horses (4 healthy; 6 with recurrent airway obstruction [heaves] in remission). PROCEDURE: Healthy horses (group-A horses) and heaves-affected horses (group-B horses) were housed in a controlled environment. At each step of a methacholine bronchoprovocation test, threshold concentration (TC(2SD); results in a 2-fold increase in SD of a value) and sensitivity index (SI) were determined for respiratory tract system resistance (R(rs)) and respiratory tract system reactance (X(rs)) at 5 to 20 Hz by use of IOS and for total pulmonary resistance (RL) and dynamic lung compliance (C(dyn)), by use of CRT. RESULTS: Bronchoconstriction resulted in an increase in R(rs) at 5 Hz (R(5Hz)) and a decrease in X(rs) at all frequencies. Most sensitive parameters were X(rs) at 5 Hz (X(5Hz)), R(5Hz), and R(5Hz):R(10Hz) ratio; RL and the provocation concentration of methacholine resulting in a 35% decrease in dynamic compliance (PC(35)C(dyn)) were significantly less sensitive than these IOS parameters. The TC(2SD) for X(rs) at 5 and 10 Hz was significantly lower in group-B horses, compared with group-A horses. The lowest TC(2SD) was obtained for X(5Hz) in group-B horses and R(5Hz) in group-A horses. CONCLUSIONS AND CLINICAL RELEVANCE: In contrast to CRT parameters, IOS parameters were significantly more sensitive for testing pulmonary function.The IOS provides a practical and noninvasive pulmonary function test that may be useful in assessing subclinical changes in horses.
Afficher plus [+] Moins [-]A meta-analysis review of the effects of recombinant bovine somatotropin. 1. Methodology and effects on production
2003
Dohoo, I.R. | Leslie, K. | DesCôteaux, L. | Fredeen, A. | Dowling, P. | Preston, A. | Shewfelt, W.
This manuscript presents the results of a review of the effects of recombinant bovine somatotropin (rBST) on milk production, milk composition, dry matter intake, and body condition score that was carried out by an expert panel established by the Canadian Veterinary Medical Association (CVMA). The panel was established by the CVMA in response to a request from Health Canada in 1998 and their report was made public in 1999. A series of meta-analyses was used to combine data on production and nutrition related parameters that were extracted from all randomized clinical trials, which had been published in peer-reviewed journals or which were provided by Health Canada, from the submission by Monsanto for registration of rBST in Canada. A companion paper will present the results of the effects of the drug on measures of health, reproductive performance, and culling parameters. Recombinant bovine somatotropin was found to increase milk production by 11.3% in primiparous cows and 15.6% in multiparous cows; although there was considerable variation from study to study. While some statistically significant effects on milk composition (% butterfat, protein, and lactose) were found, they were all very small. Treatment increased dry matter intake by an average 1.5 kg/day during the treatment period and dry matter intake remained elevated on into the first 60 days of the subsequent lactation. Despite the increase in dry matter intake, treated animals had lower body condition scores at the end of the treatment period, and the reduced scores persisted through until the start of the subsequent lactation.
Afficher plus [+] Moins [-]Pharmacokinetics and tissue concentrations of azithromycin in ball pythons ( Python regius )
2003
Coke, Rob L. | Hunter, Robert P. | Koch, David E. | Goatley, Marie A. | Carpenter, James W.
Objective-To determine pharmacokinetics and tissue concentrations of azithromycin in ball pythons ( Python regius ) after IV or oral administration of a single dose. Animals-2 male and 5 female ball pythons. Procedures-Using a crossover design, each snake was given a single dose of azithromycin (10 mg/kg) IV. After a 4-week washout period, each snake was given a single dose of azithromycin (10 mg/kg) orally. Blood samples were collected prior to dose administration and 1, 3, 6, 12, 24, 48, 72, and 96 hours after azithromycin administration. Azithromycin was quantitated by use of liquid chromatography-mass spectrometry. Results-After IV administration, azithromycin had an apparent volume of distribution of 5.69 L/kg and a plasma clearance of 0.19 L/h/kg. Harmonic means for the terminal half-life were 17 hours following IV administration and 51 hours following oral administration. Mean residence times were 37 and 94 hours following IV and oral administration, respectively. Following oral administration, azithromycin had a peak plasma concentration (Cmax) of 1.04 micrograms/mL, a time to Cmax of 8.4 hours, and a prolonged mean absorption time of 57 hours. Mean oral bioavailability was 77%. Tissue concentrations ranged from 4 to 140 times the corresponding plasma concentration at 24 and 72 hours after azithromycin administration. Conclusions and Clinical Relevance-Azithromycin is well absorbed and tolerated by ball pythons. On the basis of plasma pharmacokinetics and tissue concentration data, we suggest an azithromycin dosage in ball pythons of 10 mg/kg, orally, every 2 to 7 days, depending upon the site of infection and susceptibil ity of the infective organism.
Afficher plus [+] Moins [-]Serum acute phase proteins and swine health status
2003
Chen, Hsin-Hsin | Lin, Jyh-Hung | Fung, Hang-Pong | Ho, Lin-Lin | Yang, Ping-Chin | Lee, Wen-Chuan | Lee, Yan-Pai | Chu, Rea-Min
The purpose of this study was to investigate the relationship between swine health status and the concentration of the serum acute phase proteins, haptoglobin (HP), and C-reactive protein (CRP). A total of 378 clinically healthy pigs from farms A and B, plus 20 pigs culled from farm A due to poor growth, were used in this experiment. Each pig was examined and blood samples were collected during slaughter. The HP concentration was measured by using an HP-hemoglobin binding assay. The CRP concentration was measured by using a CRP enzyme immunoassay. Gross and histopathological lesions were examined and recorded at slaughter. Representative samples were then collected in order to isolate pathogens. Swine enzootic pneumonia, found in 47.7% of the pigs, was the most common lesion. Other lesions included pleuropneumonia (32.7%), suppurative pneumonia (10.3%), fibrinous pericardititis (4.3%), Ascaris migration in the liver (33.9%), and intestinal serositis (3.0%). On farm A, the percentage of pigs with 1 or more lesions was 88.2%. For culled pigs from farm A, the mean serum concentrations of HP and CRP were 2.23 +/- 0.14 mg/mL and 252.93 +/- 11.62 μg/mL, which were significantly higher than concentrations in clinically normal pigs (1.42 +/- 0.02 mg/mL and 84.88 +/- 2.61 μg/mL, respectively, P < 0.01). Moreover, among clinically normal farm A pigs, the mean HP concentration in pigs with lesions (1.43 +/- 0.02 mg/mL) was significantly higher than in pigs without lesions (1.32 +/- 0.07 mg/mL) (P < 0.05). However, the mean serum CRP concentrations in these animals were not significantly different. On farm B, the percentage of pigs with one or more lesions was 50.0%. Interestingly, the mean serum HP concentration in clinically normal pigs with lesions was significantly lower in farm B pigs (1.23 +/- 0.07 mg/mL) than in the farm A pigs (1.43 +/- 0.02 mg/mL; P < 0.01). However, serum CRP concentrations in farm A and B pigs were not significantly different. Serum HP concentration, which is a better indicator of inflammatory reactions in pig herds than serum CRP concentration, provides an important marker for swine health status.
Afficher plus [+] Moins [-]A meta-analysis review of the effects of recombinant bovine somatotropin. 2. Effects on animal health, reproductive performance, and culling
2003
Dohoo, I.R. | DesCôteaux, L. | Leslie, K. | Fredeen, A. | Shewfelt, W. | Preston, A. | Dowling, P.
This manuscript presents the results of a review of the effects of recombinant bovine somatotropin (rBST) on dairy cattle health, reproductive performance, and culling, that was carried out by an expert panel established by the Canadian Veterinary Medical Association (CVMA). The panel was established by the CVMA in response to a request from Health Canada in 1998 and their report was made public in 1999. A series of meta-analyses was used to combine data on health-related parameters that were extracted from all randomized clinical trials that had been published in peer-reviewed journals or which were provided by Health Canada from the submission by Monsanto for registration of rBST in Canada. A companion paper (1) presents the estimates of the effect of the drug on production parameters. Recombinant bovine somatotropin was found to increase the risk of clinical mastitis by approximately 25% during the treatment period but there was insufficient data to draw firm conclusions about the effects of the drug on the prevalence of subclinical intra-mammary infections. Use of rBST increased the risk of a cow failing to conceive by approximately 40%. For cows which did conceive, there was no effect on services per conception and only a small increase in average days open (5 days). Use of the drug had no effect on gestation length, but the information about a possible effect on the risk of twinning was equivocal. Cows treated with rBST had an estimated 55% increase in the risk of developing clinical signs of lameness. Few studies reported data on culling, but based on those that did, there appeared to be an increase risk of culling evident in multiparous cows. Use of the drug in 1 lactation period appeared to reduce the risk of metabolic diseases (particularly ketosis) in the early period of the subsequent lactation.
Afficher plus [+] Moins [-]Accuracy of pulse oximetry and capnography in healthy and compromised horses during spontaneous and controlled ventilation
2003
Koenig, Judith | McDonell, Wayne | Valverde, Alex
The objective of this prospective clinical study was to evaluate the accuracy of pulse oximetry and capnography in healthy and compromised horses during general anesthesia with spontaneous and controlled ventilation. Horses anesthetized in a dorsal recumbency position for arthroscopy (n = 20) or colic surgery (n = 16) were instrumented with an earlobe probe from the pulse oximeter positioned on the tip of the tongue and a sample line inserted at the Y-piece for capnography. The horses were allowed to breathe spontaneously (SV) for the first 20 min after induction, and thereafter ventilation was controlled (IPPV). Arterial blood, for blood gas analysis, was drawn 20 min after induction and 20 min after IPPV was started. Relationships between oxygen saturation as determined by pulse oximetry (SpO2), arterial oxygen saturation (SaO2), arterial carbon dioxide partial pressure (PaCO2), and end tidal carbon dioxide (P(et)CO2), several physiological variables, and the accuracy of pulse oximetry and capnography, were evaluated by Bland–Altman or regression analysis. In the present study, both SpO2 and P(et)CO2 provided a relatively poor indication of SaO2 and PaCO2, respectively, in both healthy and compromised horses, especially during SV. A difference in heart rate obtained by pulse oximetry, ECG, or palpation is significantly correlated with any pulse oximeter inaccuracy. If blood gas analysis is not available, ventilation to P(et)CO2 of 35 to 45 mmHg should maintain the PaCO2 within a normal range. However, especially in compromised horses, it should never substitute blood gas analysis.
Afficher plus [+] Moins [-]Development and analytic validation of an enzyme-linked immunosorbent assay for the measurement of canine pancreatic lipase immunoreactivity in serum
2003
Steiner, Jörg M. | Teague, Sheila R. | Williams, David A.
Recently, a radioimmunoassay (RIA) for measurement of canine pancreatic lipase immunoreactivity (cPLI) in serum was developed and validated. However, RIAs require frequent use of radioactive materials. Therefore, the goal of this project was to develop and validate an enzyme-linked immunosorbent assay (ELISA) for cPLI. After purifying cPL, we developed and purified antiserum against cPL in rabbits. The purified antibody was bound to microtitre plates and used to capture antigen. A portion of the purified antibody was biotinylated and used to identify the captured antigen. Streptavidin labelled with horseradish peroxidase and a horseradish peroxidase substrate were used for detection. The assay was validated by determination of sensitivity, working range, linearity, accuracy, precision, and reproducibility. The reference interval for serum cPLI was determined by the central 95th percentile in 74 clinically healthy dogs: 2.2 to 102.1 μg/L. The sensitivity and the upper limit of the working range were 0.1 and 999.2 μg/L, respectively. The ratios of observed to expected values for dilutional parallelism for 6 serum samples ranged from 0.0 to 148.8%; the ratios for spiking recovery for 4 serum samples ranged from 90.4 to 112.6%, assuming 55% recovery of the cPL. Coefficients of variation for intra- and interassay variability for 6 different serum samples were 2.4, 3.4, 4.1, 5.8, 7.4, and 10.0% and 5.9, 7.7, 11.6, 13.9, 23.5, and 46.2%, respectively. We conclude that the ELISA described here is sufficiently sensitive, linear, accurate, precise, and reproducible for clinical application. Evaluation of its clinical usefulness for the diagnosis of exocrine pancreatic disorders in dogs is under way.
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