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1.
Animals (Basel) ; 13(1)2022 Dec 24.
Artículo en Inglés | MEDLINE | ID: mdl-36611681

RESUMEN

Throughout their lives, dogs may experience various stressful events. Early neurological stimulation (ENS), which was shown to alter stress responses beneficially in some animals, has not been fully explored in dogs. Seventy-six small-breed puppies from one commercial breeding kennel were divided into three treatment groups: ENS, held, and control. Puppies in the ENS group received 30 s of handling exercises for 21 days after birth; puppies in the held group were simply held for the same amount of time. Puppies in the control group were managed as per normal breeder practices (i.e., routine husbandry and physical health checks). Physical health was assessed weekly, and puppies were generally healthy and clean. Behavioral responses to stranger approach and isolation tests were evaluated pre- and post-ground-transportation to a distributor. Puppies were more affiliative toward a stranger post-isolation than pre-isolation (p < 0.001), and post-transport than pre-transport (p < 0.001). At the distributor, puppies in the isolation test spent less time in exploratory locomotion (p < 0.001) and vocalized more than at the breeder's kennel (p = 0.011). Treatment did not affect these results. Overall, the results suggest that the type of ENS used in this study may not provide the purported benefits to puppies' stress responses in commercial breeding populations.

2.
Animals (Basel) ; 12(20)2022 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-36290206

RESUMEN

Poor dam welfare throughout the peri-parturient period can also negatively affect that of their offspring. This study aimed to identify changes in physical, physiological, and behavioral metrics indicative of dam welfare throughout the peri-parturient period. Dams (n = 74) from eight U.S. Midwest commercial breeding (CB) kennels were tested at 6 and 1 week prepartum, and 4 and 8 weeks postpartum. At each time point dams underwent a stranger approach test, physical health assessment, hair collection for hair cortisol concentration (HCC) and fecal collection for fecal glucocorticoid metabolites (FGM), fecal secretory immunoglobulin A (sIgA) and parasite detection. Linear mixed-effects models indicated dams exhibited more affiliative behaviors towards the stranger at 4 weeks postpartum than 6 weeks prepartum (p = 0.03), increased HCC from 4-weeks to 8 weeks postpartum (p = 0.02), and increased FGM from 1 week prepartum to 8 weeks postpartum (p = 0.04). At each respective time point, the percentage of dams with intestinal parasites was 11%, 4%, 23%, and 15%. Most changes are likely due to increased energy requirements and hormonal variations. However, deviations from expected changes may have resulted from changes in environment and/ or management, which should be explored in future studies.

3.
Animals (Basel) ; 12(23)2022 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-36496902

RESUMEN

Many puppies from commercial breeding kennels (CBKs) are transported by ground from their kennels of origin to a distributor. This experience may elicit fear and stress during a sensitive developmental period, which may in turn negatively impact the puppies' short- and long-term welfare. This study aimed to measure short-term effects of transportation on puppy welfare metrics. Eight-week-old puppies (n = 383) from 12 CBKs were tested at their kennels (pre-trans) and ~48 h after arriving at a distributor (post-trans). At each location, puppies underwent an isolation test, a stranger-approach test, and a physical health assessment. Behavioral responses to testing were scored from videos. Fecal glucocorticoid metabolites (FGM), fecal secretory immunoglobulin A (sIgA), and presence of intestinal parasites were also analyzed. Linear mixed-effects models identified decreased exploration (p < 0.001), and increased locomotion (p < 0.001) and escape attempts (p = 0.001) during the post-trans isolation test. Increased affiliative behavior (p < 0.001), FGM (p < 0.001) and sIgA (p = 0.014) were also observed post-trans. Findings support good physical health both pre- and post-trans, while behavioral and physiological changes suggest increased puppy distress post-trans. Higher post-transport affiliative behavior may indicate that puppies sought social support as a coping strategy after experiencing transport-related distress. Future studies should explore the efficacy of transportation-related interventions to mitigate puppy distress.

4.
Biosens Bioelectron ; 22(11): 2400-7, 2007 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-17023153

RESUMEN

An in vivo enzyme-based biosensor platform was developed that uses specific oxygenase enzymes to detect aromatic compounds in water. Bacteria capable of degrading highly reduced hydrocarbons initiate substrate oxidation using well-characterised oxygenase enzymes, which due to their specificity, stability and high activity can be applied in vivo as biosensor components. Oxygenase enzyme activity was determined in vivo using BD Oxygen Biosensor plates to measure oxygenase-mediated oxygen depletion in the presence of specific aromatic analytes. The BTEX family of compounds (benzene, toluene, ethylbenzene and the three isomers of xylene) were used as model compounds. Detection limits and sensitivity achieved using this approach (microM detection range) was similar to levels achieved with oxygen electrode-based and some recombinant DNA-based approaches. No significant signals were detected with hydrocarbons that were not substrates of the initial oxygenases.


Asunto(s)
Bacterias Aerobias/enzimología , Bioensayo/métodos , Técnicas Biosensibles/métodos , Contaminantes Ambientales/análisis , Hidrocarburos Aromáticos/análisis , Oxígeno/análisis , Oxigenasas/química , Bioensayo/instrumentación , Técnicas Biosensibles/instrumentación , Hidrocarburos Aromáticos/química , Reproducibilidad de los Resultados , Sensibilidad y Especificidad
5.
Biosens Bioelectron ; 22(5): 759-63, 2006 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-16487702

RESUMEN

A new rapid biosensor method employing the dye resazurin as an indicator of bacterial respiration has been developed to provide a rapid, facile and specific biosensor for environmental contaminants that does not rely on genetic modification techniques, is suitable for a high-throughput multiwell format, and is ideally suited to resource-constrained environmental monitoring situations. This whole-cell biosensor has been applied to the test analyte toluene using natural toluene-degrading bacteria as the biological component and is competitive with more complex recombinant approaches. The redox-driven biosensor is dependent on the catabolism of a specific compound, concomitantly reducing the redox indicator resazurin to provide the analytical signal in a whole-cell biosensor assay.


Asunto(s)
Bioensayo/métodos , Técnicas Biosensibles/métodos , Burkholderia cepacia/metabolismo , Oxazinas/análisis , Pseudomonas/metabolismo , Tolueno/análisis , Tolueno/farmacología , Xantenos/análisis , Bioensayo/instrumentación , Técnicas Biosensibles/instrumentación , Burkholderia cepacia/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Monitoreo del Ambiente/métodos , Contaminantes Ambientales/análisis , Contaminantes Ambientales/farmacología , Compuestos Orgánicos/análisis , Compuestos Orgánicos/farmacología , Oxazinas/metabolismo , Pseudomonas/efectos de los fármacos , Xantenos/metabolismo
6.
J Microbiol Methods ; 60(2): 217-24, 2005 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-15590096

RESUMEN

The genus Pseudomonas contains fast-growing nutritionally versatile bacteria that are able to utilize a wide variety of carbon sources. The ubiquity of the genus has been highlighted by conventional microbiology and the genus is well represented in collections of cultured bacteria. Here we evaluate the Pseudomonas population in New Zealand soils by comparing a culture-independent (real-time PCR combined with fluorescent TaqMan technology) with a culture-dependent (Gould's S1) population estimate. We show that cultivated fluorescent pseudomonads are not numerically dominant and represent a small proportion of <1% of the total Pseudomonas population, and that the total Pseudomonas population itself represents only a small proportion of <1% of the total bacterial population.


Asunto(s)
Reacción en Cadena de la Polimerasa/métodos , Pseudomonas/aislamiento & purificación , Técnicas Bacteriológicas/métodos , Recuento de Colonia Microbiana , ADN Bacteriano/química , ADN Bacteriano/genética , Nueva Zelanda , Pseudomonas/genética , Pseudomonas/crecimiento & desarrollo , ARN Ribosómico 16S/química , ARN Ribosómico 16S/genética , Microbiología del Suelo , Polimerasa Taq/metabolismo
7.
Gene ; 38(1-3): 9-17, 1985.
Artículo en Inglés | MEDLINE | ID: mdl-2998951

RESUMEN

A 10.9-kb segment of the Bacillus subtilis 168 chromosome has been cloned in an Escherichia coli plasmid and shown to contain terC (the replication terminus of the chromosome). The terC-containing portion of this plasmid has been subcloned within each of two overlapping fragments of DNA, 1.75 and 1.95 kb, again in E. coli plasmids. These have afforded a more precise definition of the location of terC in the B. subtilis chromosome and provided material for a detailed analysis of the structure and functioning of this site.


Asunto(s)
Bacillus subtilis/genética , Replicación del ADN , ADN Bacteriano/genética , Mapeo Cromosómico , Clonación Molecular , Enzimas de Restricción del ADN , ADN Bacteriano/biosíntesis , Plásmidos
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