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Antimicrobial susceptibility profile of Campylobacter spp. isolated from different animal species in Minas Gerais
2017
Cristiane Pinheiro Toscano de Brito | Elaine Maria Seles Dorneles | Telma Maria Alves | Ana Paula Reinato Stynen | Andrey Pereira Lage
Universidade Federal de Minas Gerais, Escola de Veterinária, Departamento de Medicina Veterinária Preventiva, Laboratório de Bacteriologia AplicadaSusceptibility pattern of 45 Campylobacter spp.isolates – 16 C. jejuni, eight C. coli, and 21 C. fetus isolated from different animal species in Brazil – to twelve antimicrobial agents was determined. All Campylobacter spp. isolates were susceptible to gentamicin, sulfadiazine, and sulfamethoxazole. C. jejuni and C. coli were also sensitive to chloramphenicol, whereas all C. fetus strains were susceptible to kanamycin. Cefoperazone showed the highest percentage of resistance among C. jejuni (68.75%), followed by nalidixic acid (31.25%), ampicillin (37.50%), tetracycline (37.50%), erythromycin (12.50%), and kanamycin (6.25%). Likewise, cefoperazone exhibited the highest percentage of resistance among C. coli (75.00%), followed by nalidixic acid (50.00%), tetracycline (50.00%), erythromycin (37.50%), ampicillin (12.50%), and kanamycin (12.50%). Among C. fetus strains, nalidixic acid showed the highest resistance rate (85.71%), followed by cefoperazone (71.43%), tetracycline (42.86%), ampicillin (19.05%), chloramphenicol (9.52%), and erythromycin (4.76%). Therefore, it was found that the majority of Campylobacter spp. isolated from animals was sensitive to gentamycin, chloramphenicol, kanamacyn, and sulfonamides; however, a high proportion of the strains showed reduced susceptibility to nalidixic acid, ampicillin, cefoperazone, and tetracycline. Moreover, C. coli and C. fetus isolates showed a high percentage of multidrug resistant strains.
Показать больше [+] Меньше [-]The involvement of the hypothalamopituitary-adrenocortical axis in stress physiology and its significance in the assessment of animal welfare in cattle
2017
Emma J. Brown | Andre Vosloo
The intensification of cattle production has raised concern for animal welfare due to the stress that is associated with farming practices. The welfare of an animal is determined by the animal’s ability to cope with or adapt to its continuously changing environment and the biological cost that is associated with this adaptation and maintenance. Stressors arise from various psychological, physiological and physical aspects of farming practices due to management and human–cattle interactions. Measuring the activity of the hypothalamopituitary-adrenocortical (HPA) axis with plasma cortisol levels is a useful method for determining the effects of stress on animals as it is stimulated at the onset of a perceived stress. The activation of the HPA axis affects various target tissues or systems and can result in suppression of the immune system, increased susceptibility to disease and adverse effects on reproductive success in prenatal and neonatal calves. Although some levels of stress associated with farming practices are unavoidable, improvements in farming methods need to be implemented in order to maintain or increase the efficiency of cattle production in a way that does not compromise the welfare of the animal.
Показать больше [+] Меньше [-]Beef tenderness improvement by dietary vitamin D3 supplementation in the last stage of fattening of cattle
2017
Półtorak, Andrzej | Moczkowska, Małgorzata | Wyrwisz, Jarosław | Wierzbicka, Agnieszka
Tenderness is the most important characteristic of meat, determining consumer approval. There are numerous methods of its improvement, although of diverse effectiveness. addition of vitamin D₃ to the feed for a short period before slaughter (7–10 days) is one of the natural ways to enhance the tenderness. Vitamin D₃ is responsible for Ca²⁺ mobilisation in serum and increase in activity of proteolytic enzymes belonging to calpains, which results in significant improvement of beef tenderness and reduction of ageing time. The use of vitamin D₃ is an application tool determining tenderness improvement of beef with substantial reduction in processing costs. Moreover, shorter post mortem ageing process will exceed the retail display time, which will consequently reduce losses due to unsold meat being returned from shops to the manufacturers. Based on the results of studies conducted over the last 15 years, this paper presents the possibility and the effects of the use of vitamin D₃ to improve beef tenderness.
Показать больше [+] Меньше [-]Evaluation of susceptibility to antimycobacterial drugs in Mycobacterium tuberculosis complex strains isolated from cattle in Poland
2017
Krajewska-Wędzina, Monika | Zabost, Anna | Augustynowicz-Kopeć, Ewa | Weiner, Marcin | Szulowski, Krzysztof
Introduction: Tuberculosis is a highly infectious disease affecting humans and animals. It is caused by the Mycobacterium tuberculosis complex (MTBC) – Mycobacterium bovis and Mycobacterium caprae, which are aetiological factors of bovine tuberculosis (bTB). In Poland, the bTB eradication programme exists. Animals diagnosed with tuberculosis are in the majority of cases not treated, but removed from their herd and then sanitary slaughtered. Material and Methods: In total, 134 MTBC strains isolated from cattle in Poland were subjected to microbiological analysis. The resistance phenotype was tested for first-line antimycobacterial drugs used in tuberculosis treatment in humans: streptomycin, isoniazid, rifampicin, ethambutol, and pyrazinamide. The strains were isolated from tissues collected post mortem, so the test for drug resistance fulfilled only epidemiological criterion. Results: The analysis of drug-resistance of MTBC strains revealed that strains classified as M. bovis were susceptible to 4 antimycobacterial drugs: isoniazid, rifampicin, streptomycin, and ethambutol, and resistant to pyrazynamide. The strains classified as M. caprae were sensitive to all tested drugs. Conclusion: The results indicate that despite enormously dynamic changes in mycobacterial phenotype, Polish strains of MTBC isolated from cattle have not acquired environmental resistance. The strains classified as M. bovis are characterised by natural resistance to pyrazinamide, which is typical for this species.
Показать больше [+] Меньше [-]Development of LC-MS/MS confirmatory method for the determination of testosterone in bovine serum
2017
Woźniak-Sobczak, Barbara | Matraszek-Żuchowska, Iwona | Witek, Sebastian | Posyniak, Andrzej
Introduction: In the European Union the use of steroid growth promoters is prohibited under Council Directive 96/22/EC. For effective control of illegal use of natural steroids, highly sensitive analytical methods are required, because sex hormones can be present in very low concentrations in biological samples. The aim of the study was to develop a confirmatory method for the detection of testosterone in bovine serum at ppt level. Material and Methods: 17β-testosterone and internal standards of 17β-testosterone-d2 were extracted from serum samples with a mixture of tert-butyl methyl ether/petroleum ether and were directly analysed by an LC/MS/MS on QTRAP 5500 instrument with a TurboIon-Spray source operating in a positive ionisation mode. Chromatographic separation was achieved on the analytical column Inertsil® ODS-3 with an isocratic elution using mobile phase consisting of acetonitrile, methanol, and water. Method validation has been carried out in accordance with the Commission Decision 2002/657/EC. Results: The method was characterised by good recovery (82%) and precision (R.S.D 17 %). Decision limit (CCα) and detection capability (CCβ) was 0.05 μg L⁻¹ and 0.09 μg L⁻¹ respectively. The method met the criteria set out in Commission Decision 2002/657/EC for the purpose of confirmation in terms of retention time and ion ratio in the whole range of its application. Conclusions: The developed method is specific and sensitive, suitable for measuring the natural level of testosterone in blood of cattle and for use in routine control programme for the detection of this hormone in bovine serum.
Показать больше [+] Меньше [-]Development of a recombinant protein-based ELISA for detection of antibodies against bovine foamy virus
2017
Materniak-Kornas, Magdalena | Osiński, Zbigniew | Rudzki, Marcin | Kuźmak, Jacek
Introduction: Infections with bovine foamy virus (BFV) were found in many countries but there is a lack of large-scale surveys on the prevalence of BFV among dairy cattle. The aim of this study was to develop and validate the recombinant Gag protein-based ELISA and to estimate the prevalence of antibodies against BFV. Material and Methods: Gag coding region from BFV was cloned into expression vector pT7Arg-STOP, which expressed a high level of recombinant Gag protein from E.coli. The ELISA was standardised, and the cut-off value and sensitivity and specificity of the test were calculated using a receiver operating characteristic and Bayesian estimation. Results: A total of 3,051 serum samples were tested by ELISA and 939 (30.8%) sera were recognised as positive. When Bayesian approach was used, the overall true BFV prevalence was 29.7% (95% CI: 25.9-33.4%). Conclusion: Expressed Gag protein of BFV has been used successfully as an antigen for ELISA. Eventually, this study provides basic information about the epidemiological status of infection with BFV in dairy cattle in Poland, which can be used for further studies on dissemination and transmission of BFV infection.
Показать больше [+] Меньше [-]Inventory of medicinal plants used in the treatment of diseases that limit milk production of cow in Benin
2017
Nestor Dé | nakpo Noudè | kè | Ignace Dotché | Gbê | nagnon Serge Ahounou | Issaka Youssao Abdou Karim | Souaï | bou Farougou
Objective: This study aimed to make an inventory of animal diseases that affect milk production and the plants locally used against these diseases. Materials and methods: A survey was carried out from April to August 2013 in 41 farms in department of Collines, 40 in Alibori, 40 in Borgou and 21 in Mono using questionnaires. SAS software was used with Chi-square test and bilateral Z test. Results: The study revealed twelve main pathologies that limit milk production. Among these pathologies, foot-and-mouth disease and trypanosomiasis were the most mentioned pathologies. To fight these pathologies, 60 medicinal plants of 32 families were recorded. The most cited families were Leguminosae (31.67%), Combretaceae (6.67%), Meliaceae (5%) and Rubiaceae (5%), whereas the predominant species used by animal keepers were Khaya senagalensis, Vitellaria paradoxa, Parkia biglobosa and Securidaca longipedunculata. The 60 listed species were used in 85 recipes which varied from one department and farmer to another. The most used organs were plant barks (41.06%) and roots (31.13%), while the most common methods of preparation were decoction (37.5%), maceration (32.5%) and powders (22.5%). Oral route was the main route of administration.Conclusion: The inventory has shown that the important pathologies are foot-and-mouth disease and trypanosomiasis. This needs immediate actions. Barks and roots were the commonly employed plant organs used as infusion (decoction and maceration) and powder that farmers administer orally to animals. The harvest did not require a special season or time. Furthermore, farmers inherited most of these recipes from their parents and they use them because of their effectiveness. [J Adv Vet Anim Res 2017; 4(1.000): 1-14]
Показать больше [+] Меньше [-]Reduced activities of thiamine-dependent and cytochrome c oxidase enzymes in cerebral cortex of cattle affected by sulfur-induced polioencephalomalacia
2017
Amat, Samat | Hendrick, Steve | Moshynskyy, Igor | Simko, Elemir
Sulfur-induced polioencephalomalacia (PEM) is an important disease affecting cattle in certain geographical regions. However, the pathogenesis of brain damage is not completely understood. We previously observed that excess dietary sulfur may influence thiamine status and altered thiamine metabolism may be involved in the pathogenesis of sulfur-induced PEM in cattle. In this study, we evaluated the activities of thiamine-dependent enzymes [α-ketogluterate dehydrogenase (α-KGDH) and pyruvate dehydrogenase (PDH)] and cytochrome c oxidase (COX) in the cerebral cortex of sulfur-induced PEM-affected cattle (n = 9) and clinically normal cattle (n = 8, each group) exposed to low or high dietary sulfur [LS = 0.30% versus HS = 0.67% sulfur on a dry matter (DM) basis]. Enzyme activities in PEM brains were measured from the brain tissue regions and examined using ultraviolent (UV) light illumination to show fluorescence or non-fluorescence regions. No gross changes under regular or UV light, or histopathological changes indicative of PEM were detected in the brains of cattle exposed to LS or HS diets. The PDH, α-KGDH, and COX activities did not differ between LS and HS brains, but all enzymes showed significantly lower (P < 0.05) activities in UV-positive region of PEM brains compared with LS and HS brains. The UV-negative regions of PEM brain had similar PDH activities to LS and HS brains, but the activities of α-KGDH and COX were significantly lower than in LS and HS brains. The results of this study suggest that reduced enzyme activities of brain PHD, α-KGDH, and COX are associated with the pathogenesis of sulfur-induced PEM.
Показать больше [+] Меньше [-]Towards an improved estimate of antimicrobial use in animals: Adjusting the "population correction unit" calculation
2017
Radke, B. R.
International comparisons of animal antimicrobial use (AMU) have typically been based on total national estimates of antimicrobials sales standardized by the national animal biomass calculated as the population correction unit (PCU). The objective of this paper was to compare the currently accepted PCU calculation with that of the adjusted population correction unit (APCU), which re-evaluates the standard animal weights used in the calculation and accounts for animal lifespan. The APCU calculation resulted in substantial changes to the 2009 national biomass estimates for cattle, pigs, and poultry in 8 European countries and Canada. The estimated national biomass for cattle increased 35% to 43%, while the estimated national biomass of pigs and poultry typically decreased by approximately 51% and 87%, respectively. Among the 9 countries, the total national APCU ranged from an increase of 1% to a decrease of 40% relative to PCU, and these differences were statistically significant. Adjusted population correction unit is preferred over PCU in comparing and contrasting AMU among animals with different lifespans because it is more transparently derived and is a reasonable approximation of the animal biomass at risk of antimicrobial treatment.
Показать больше [+] Меньше [-]Evaluation of pathogen-specific biomarkers for the diagnosis of tuberculosis in white-tailed deer (Odocoileus virginianus)
2017
Wanzala, Sylvia I. | Palmer, Mitchell V. | Waters, Wade R. | Thacker, Tyler C. | Carstensen, Michelle | Travis, Dominic A. | Sreevatsan, Srinard
OBJECTIVE To develop a noninvasive biomarker-based detection system specific for Mycobacterium bovis for monitoring infection in wild animals. SAMPLE Serum samples from 8 experimentally infected yearling white-tailed deer (Odocoileus virginianus) and 3 age-matched control deer and from 393 Minnesota Department of Natural Resources hunter-harvested white-tailed deer in northwest Minnesota. PROCEDURES 8 yearling deer were inoculated with 2 × 10(8) CFUs of virulent M bovis strain 1315 (day 0), and sera were obtained on days 0, 19, 48, and 60; sera were obtained from 3 uninoculated control deer on those same days. Sera from these deer and 9 M bovis-positive hunter-harvested deer were tested for 3 Mycobacterium-specific biomarkers (MB1895c, MB2515c, and polyketide synthase 5) by use of an indirect ELISA. That same ELISA was used to test sera obtained from 384 exposed noninfected deer in northwest Minnesota from 2007 through 2010, concurrent with an outbreak of tuberculosis involving cattle and deer in that region. RESULTS ELISA results revealed that tuberculosis infection could be detected as early as 48 days after inoculation in experimentally infected deer. Results for 384 deer sera revealed that prevalence of tuberculosis decreased over the 4-year period. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that the prevalence of tuberculosis in Minnesota deer decreased after 2009 but tuberculosis may have persisted (as subclinical disease) at extremely low levels, as indicated by the presence of low concentrations of circulating biomarkers. Biomarker-based diagnostic tests may offer a specific approach for early identification of M bovis infection.
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