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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
481

Care and treatment of women with inflammatory symptoms of the breast during lactation

Kvist, Linda J. January 2006 (has links)
<p>Care and treatment of women with inflammatory symptoms of the breast during lactation</p><p>Inflammation of the breast during lactation causes considerable discomfort to mothers and carries a risk of early abandonment of breastfeeding. Little is known about the effects of care interventions, including acupuncture, used for these mothers or about mothers’ experiences of the complaint. Aim: to study care and treatment given at a midwife-led breastfeeding clinic to mothers with inflammatory symptoms of the breast during lactation, to gain knowledge of mothers’ experiences of being afflicted by breast inflammation and to investigate factors which may be associated with the development of breast abscess. Methods: method triangulation was used to study different aspects of the phenomenon of inflammatory symptoms of the breast during lactation; two randomised controlled trials I (n = 88) and II (n = 210), a descriptive study III (n = 210), an interview study with a Grounded Theory approach IV (n = 14), and a population-based register study V (n = 1,454,068 singleton deliveries). Results: mothers’ symptoms were more effectively relieved when acupuncture was used but acupuncture treatment did not shorten contact with health services. Nine percent (I) and 15 % (II) respectively, of mothers were prescribed antibiotics. Twelve percent experienced renewed symptoms requiring health care contact within 6 weeks (III). Seven mothers (0.1% of breastfeeding mothers) developed breast abscess, which was comparable to the figure in the population-based study (V). The presence of Group B streptococci in the breast milk was related to longer contact with health care (II). Mothers’ “will to breastfeed” may make it possible for them to withstand physical and emotional difficulties caused by the illness. Mothers considered access to clinical expertise to be an important factor in their care (IV). Primiparous mothers, those over the age of 30 years and those who give birth after 41 weeks gestation appear to be at a significantly increased risk for the development of breast abscess (V).</p><p>Conclusions: mothers’ symptoms were more effectively dissipated when acupuncture treatment was used. However, acupuncture treatment did not shorten mothers’ contact with health care services. Interventions, including acupuncture treatment for relief of symptoms may help mothers to withstand their discomfort and await the body’s own anti-inflammatory response and therefore make it possible to substantially reduce the use of antibiotic therapy for this group. The results indicate a need for a better understanding of the influence on breastfeeding of hormones administered to birthing and breastfeeding women. The availability of immediate clinical expertise is an important factor for these mothers, which health care planners should be aware of. Information on potential breastfeeding problems should be improved.</p><p>Key words: acupuncture, antibiotics, breast abscess, breastfeeding, care interventions, inflammatory symptoms, lactation mastitis</p> / <p>Vård och behandling av kvinnor med inflammation i brösten under amningsperioden</p><p>Bröstinflammation orsakar stort obehag för ammande mödrar och innebär en risk för att amning avslutas i förtid. Det finns ringa kunskap om effekterna av interventioner, inkluderande akupunktur, som används vid vård av dessa kvinnor. Det saknas även kunskap om mödrarnas upplevelser av bröstinflammation. Syfte: att studera vård och behandling av kvinnor med bröstinflammation vid en amningsmottagning ledd av barnmorskor, att utveckla kunskap om mödrars upplevelser av att vara drabbad av bröst inflammation samt att undersöka faktorer som kan ha betydelse för utvecklandet av bröstabscess. Metoder: metodtriangulering användes för att studera olika aspekter av fenomenet bröstinflammation under amningsperioden; två randomiserade kontrollerade studier I (n = 88) and II (n = 210), en deskriptiv studie III (n = 210), en intervjustudie med en grounded theory ansats IV (n = 14) och en populationsbaserat registerstudie V (n = 1 454 068 enkelbörds förlossningar). Resultat: mödrarnas symptom lindrades mer effektivt med akupunktur akupunkturbehandling men förkortade inte deras kontakt med vården. Nio procent (I) respektive 15 % (II) av mödrarna fick antibiotika. Tolv procent fick recidiv vilket föranledde kontakt med vården inom 6 veckor (III). Sju mödrar (0,1 % av ammande mödrar) utvecklade bröstabscess (II), vilket överensstämde med resultat i den populationsbaserade studien (V). Förekomsten av Grupp B streptococcer i bröstmjölken var relaterad till längre vårdkontakt (II). Mödrarnas viljan att amma kan göra det möjligt för dem att uthärda fysiska och emotionella svårigheter som sjukdomen innebär (IV). Tillgång till klinisk expertis var en viktig del av vården för dessa kvinnor. Att vara förstföderska kan innebära en något större risk för utveckling av bröstabscess. Mödrar över 30 år samt de som föder efter graviditetsvecka 41 har också en ökad risk för abscess (V).</p><p>Slutsatser: mödrarnas symptom lindrades mer effektivt när akupunktur användes. Kontakten med vården blev dock inte förkortad av akupunkturbehandling. Interventioner som inkluderar akupunkturbehandling kan tillåta mödrar att invänta kroppens anti-inflammatoriska respons och kan därför möjliggöra en avsevärd minskning av antibiotika terapi för dessa mödrar. Resultaten visar behov av att bättre förstå hur amning påverkas av hormoner administrerade till kvinnor under förlossningsarbete och amningen. Tillgång till omedelbar klinisk expertis är en viktig faktor för dessa mödrar vilket hälso- och sjukvårdsplanerare bör vara medvetna om. Förbättrad information angående potentiella amningsproblem bör eftersträvas.</p><p>Nyckelord: akupunktur, amning, antibiotika, bröstabscess, bröstinflammation, interventioner, mastit, mjölkstockning</p>
482

Care and treatment of women with inflammatory symptoms of the breast during lactation

Kvist, Linda J. January 2006 (has links)
Care and treatment of women with inflammatory symptoms of the breast during lactation Inflammation of the breast during lactation causes considerable discomfort to mothers and carries a risk of early abandonment of breastfeeding. Little is known about the effects of care interventions, including acupuncture, used for these mothers or about mothers’ experiences of the complaint. Aim: to study care and treatment given at a midwife-led breastfeeding clinic to mothers with inflammatory symptoms of the breast during lactation, to gain knowledge of mothers’ experiences of being afflicted by breast inflammation and to investigate factors which may be associated with the development of breast abscess. Methods: method triangulation was used to study different aspects of the phenomenon of inflammatory symptoms of the breast during lactation; two randomised controlled trials I (n = 88) and II (n = 210), a descriptive study III (n = 210), an interview study with a Grounded Theory approach IV (n = 14), and a population-based register study V (n = 1,454,068 singleton deliveries). Results: mothers’ symptoms were more effectively relieved when acupuncture was used but acupuncture treatment did not shorten contact with health services. Nine percent (I) and 15 % (II) respectively, of mothers were prescribed antibiotics. Twelve percent experienced renewed symptoms requiring health care contact within 6 weeks (III). Seven mothers (0.1% of breastfeeding mothers) developed breast abscess, which was comparable to the figure in the population-based study (V). The presence of Group B streptococci in the breast milk was related to longer contact with health care (II). Mothers’ “will to breastfeed” may make it possible for them to withstand physical and emotional difficulties caused by the illness. Mothers considered access to clinical expertise to be an important factor in their care (IV). Primiparous mothers, those over the age of 30 years and those who give birth after 41 weeks gestation appear to be at a significantly increased risk for the development of breast abscess (V). Conclusions: mothers’ symptoms were more effectively dissipated when acupuncture treatment was used. However, acupuncture treatment did not shorten mothers’ contact with health care services. Interventions, including acupuncture treatment for relief of symptoms may help mothers to withstand their discomfort and await the body’s own anti-inflammatory response and therefore make it possible to substantially reduce the use of antibiotic therapy for this group. The results indicate a need for a better understanding of the influence on breastfeeding of hormones administered to birthing and breastfeeding women. The availability of immediate clinical expertise is an important factor for these mothers, which health care planners should be aware of. Information on potential breastfeeding problems should be improved. Key words: acupuncture, antibiotics, breast abscess, breastfeeding, care interventions, inflammatory symptoms, lactation mastitis / Vård och behandling av kvinnor med inflammation i brösten under amningsperioden Bröstinflammation orsakar stort obehag för ammande mödrar och innebär en risk för att amning avslutas i förtid. Det finns ringa kunskap om effekterna av interventioner, inkluderande akupunktur, som används vid vård av dessa kvinnor. Det saknas även kunskap om mödrarnas upplevelser av bröstinflammation. Syfte: att studera vård och behandling av kvinnor med bröstinflammation vid en amningsmottagning ledd av barnmorskor, att utveckla kunskap om mödrars upplevelser av att vara drabbad av bröst inflammation samt att undersöka faktorer som kan ha betydelse för utvecklandet av bröstabscess. Metoder: metodtriangulering användes för att studera olika aspekter av fenomenet bröstinflammation under amningsperioden; två randomiserade kontrollerade studier I (n = 88) and II (n = 210), en deskriptiv studie III (n = 210), en intervjustudie med en grounded theory ansats IV (n = 14) och en populationsbaserat registerstudie V (n = 1 454 068 enkelbörds förlossningar). Resultat: mödrarnas symptom lindrades mer effektivt med akupunktur akupunkturbehandling men förkortade inte deras kontakt med vården. Nio procent (I) respektive 15 % (II) av mödrarna fick antibiotika. Tolv procent fick recidiv vilket föranledde kontakt med vården inom 6 veckor (III). Sju mödrar (0,1 % av ammande mödrar) utvecklade bröstabscess (II), vilket överensstämde med resultat i den populationsbaserade studien (V). Förekomsten av Grupp B streptococcer i bröstmjölken var relaterad till längre vårdkontakt (II). Mödrarnas viljan att amma kan göra det möjligt för dem att uthärda fysiska och emotionella svårigheter som sjukdomen innebär (IV). Tillgång till klinisk expertis var en viktig del av vården för dessa kvinnor. Att vara förstföderska kan innebära en något större risk för utveckling av bröstabscess. Mödrar över 30 år samt de som föder efter graviditetsvecka 41 har också en ökad risk för abscess (V). Slutsatser: mödrarnas symptom lindrades mer effektivt när akupunktur användes. Kontakten med vården blev dock inte förkortad av akupunkturbehandling. Interventioner som inkluderar akupunkturbehandling kan tillåta mödrar att invänta kroppens anti-inflammatoriska respons och kan därför möjliggöra en avsevärd minskning av antibiotika terapi för dessa mödrar. Resultaten visar behov av att bättre förstå hur amning påverkas av hormoner administrerade till kvinnor under förlossningsarbete och amningen. Tillgång till omedelbar klinisk expertis är en viktig faktor för dessa mödrar vilket hälso- och sjukvårdsplanerare bör vara medvetna om. Förbättrad information angående potentiella amningsproblem bör eftersträvas. Nyckelord: akupunktur, amning, antibiotika, bröstabscess, bröstinflammation, interventioner, mastit, mjölkstockning
483

Associations between Canadian Holstein Dairy Cattle Health and Production Traits

Weller, Denise 03 January 2013 (has links)
A multiple trait, random regression, test day (TD) model was used to determine the heritability and genetic correlations of milk, fat, protein, and SCS with metritis, cystic ovary disease, mastitis, lameness, ketosis, milk fever, and displaced abomasum for four periods in lactations 1, 2, and 3-5 using two disease definitions. Definition 1 assumed that the first disease occurrence affects all TD thereafter equally and definition 2 assumed that disease affects only the next TD. Results were similar between definitions. The models were modified to allow the estimation of differences in disease occurrence by level of production, and to estimate production differences between diseased and non-diseased cows. Few significant associations were found between production levels and disease occurrence, the largest was between MAST and SCS. Diseased animals had lower levels of production than healthy animals for all diseases except COD. Animals with MAST had increased SCS. / Natural Sciences and Engineering Research Council (NSERC). Dairy Cattle Genetics Research and Development (DairyGen) Council.
484

Mammite bovine à Escherichia coli : identification et caractérisation de la persistance

Fairbrother, Julie-Hélène 02 1900 (has links)
Escherichia coli est un agent de mammites environnementales. Par contre, E. coli peut persister dans la glande mammaire. Les objectifs de cette étude étaient de confirmer la présence d’infection persistante chez des vaches laitières canadiennes et d’identifier la possibilité de contagion entre les quartiers d’une vache dans une cohorte de 91 fermes suivies durant deux ans. De plus, les souches persistantes ont été comparées à des souches transitoires. Les profils génétiques ont été obtenus à l’aide de l’électrophorèse sur gel en champs pulsés. La détection de la résistance pour sept antibiotiques s’est faite par microdilution. Vingt-sept gènes de virulence ont été déterminés par hybridation sur colonies. De la persistance a été détectée chez 18 vaches et de la contagion entre quartiers, chez deux vaches. La proportion de résistance chez les E. coli persistants était de 0,0 % (enrofloxacin) à 27,8 % (ampicilline et tétracycline) et de 0,0 % (enrofloxacin) à 16,8 % (tétracycline) pour les E. coli transitoires. Pour chacune des résistances additionnelles, les probabilités d’être une souche persistante augmentaient par un facteur 1,6 (95% IC : 1.1, 2.4). Une souche résistante à l’ampicilline et à la céphalothine avait une plus forte probabilité d’être persistante. Une souche possédant le gène iroN avait 5.4 fois plus de probabilité (95% IC: 1.2, 24.0) d’être persistante. Aussi, une souche positive pour le gène sitA avait 8.6 fois plus de probabilité (95% IC: 2.8, 27.1) d’être persistante. En conclusion, cette étude confirme qu’E. coli peut persister dans la glande mammaire des vaches laitières canadiennes et que ces E. coli sont différents de ceux impliqués lors d’infection transitoire. / Escherichia coli is part of the environmental mastitis pathogens. However, in some cases, persistence in the mammary gland occurs. The objectives of this study were to confirm persistent infection in Canadian dairy cows and to identify possible spread between quarters of a same cow in a cohort of 91 herds monitored over two years. Also, persistent strains were compared to transient strains. Antimicrobial susceptibility was determined by the broth microdilution method. Genetic profiles were obtained for same cow isolates by DNA fingerprinting with pulsed field gel electrophoresis. Twenty-seven virulence genes were determined by colony hybridization. Persistence was detected in 18 cows and contagion between quarters, in 2 cows. Proportions of resistance in persistent E.coli ranged from 0.0% (enrofloxacin) to 27.8% (ampicillin and tetracycline). Proportion of resistance in transient E.coli ranged from 0.0% (enrofloxacin) to 16.8% (tetracycline). For each additionnal antimicrobial resistance, odds of being classified as a persistent isolate increased by a factor of 1.6 (95% CI: 1.1, 2.4). Resistance to ampicillin and to cephalothin were both associated with higher odds of being a persistent E. coli. Isolates harboring gene iroN had 5.4 times higher odds (95% CI: 1.2, 24.0) of being classified as persistent isolates. Similarly, isolates positive to virulence gene sitA had 8.6 times higher odds (95% CI: 2.8, 27.1) of being classified as persistent isolates. In conclusion, this study confirmed that E. coli can persist in the udder of Canadian dairy cows and that these E. coli are different when compared to transient E. coli.
485

Immundiagnostische Charakterisierung der bovinen Protothekenmastitis

Rösler, Uwe 28 November 2004 (has links) (PDF)
Die Protothekenmastitis des Rindes ist eine therapieresistente, weltweit vorkommende Infektionskrankheit. Das ätiologische Agens, die farblose Alge Prototheca (P.) zopfii, kommt ubiquitär in feuchten Habitaten vor und verursacht fakultativ akute bis chronische Entzündungen des Rindereuters. Es gibt Hinweise auf das Vorkommen eines speziellen, Mastitis-assoziierten Biotyps von P. zopfii, der sogenannten Variante II. Durch die oft zu beobachtende endemische Ausbreitung in Milchviehbeständen sowie durch die nachhaltige Therapieresistenz, welche oft zum wirtschaftlichen Totalverlust der betroffenen Milchkühe führt, stellen Protothekenmastitiden beim Rind ein großes ökonomisches Problem für den betroffenen Betrieb dar. Da bisher nur sehr beschränkte Erkenntnisse zur lokalen und systemischen Immunantwort sowie zur Erregerausscheidung im Verlaufe der Protothekenmastitis des Rindes vorlagen, wurden die verschiedenen klinischen Stadien dieser Infektion serologisch, kulturell sowie durch Bestimmung der Zahl der somatischen Zellen in der Milch charakterisiert. Zu diesem Zwecke wurden drei verschiedene ELISA-Systeme entwickelt, die anschließend auch auf ihren möglichen Einsatz bei der Diagnostik der Protothekenmastitis hin untersucht wurden. Dies geschah in einem hochgradig an Protothekenmastitis erkrankten Milchviehbestand. Darüber hinaus wurden verschiedene Isolate von P. zopfii auxanographisch, biochemisch, serologisch und genetisch untersucht, um eine Differenzierung innerhalb der Algenspezies P. zopfii vornehmen zu können. Anhand der auxanographischen, biochemischen, serologischen und genetischen Untersuchungen war eine eindeutige Differenzierung von drei verschiedenen Bio-, Sero- und Genotypen innerhalb der Algenspezies P. zopfii möglich. Alle untersuchten Mastitisisolate konnten eindeutig der Variante II von P. zopfii zugeordnet werden, womit dieser Variante eine besondere epidemiologische Bedeutung bei der Entstehung der Protothekenmastitis des Rindes zu zukommen scheint. Die Untersuchungen dieser Arbeit zeigen, dass akut infizierte Tiere sowohl die höchsten Antikörperaktivitäten an IgG im Blutserum sowie an IgA und IgG1 im Milchserum als auch die höchsten Gehalte an somatischen Zellen in der Milch aufweisen. Chronisch infizierte Milchkühe weisen zum Teil sehr hohe Antikörperaktivitäten in der Milch auf und unterschieden sich nicht signifikant von akut infizierten Tieren. Demgegenüber weisen diese chronisch infizierten Tiere signifikant höhere IgG-Aktivitäten im Blutserum sowie IgA- und IgG1-Aktivitäten in der Milch auf als nicht infizierte Tiere. Somit ist eine eindeutige Differenzierung zwischen infizierten und nichtinfizierten Kühen möglich. Die ELISAs zum Nachweis von spezifischem IgA und IgG1 im Milchserum erwiesen sich als besonders geeignet, um infizierte Kühe zu identifizieren. Beide serologischen Testsysteme wiesen Sensitivitäten von 96,3 % für IgA sowie 92,6 % für IgG1 und Spezifitäten von 94,4 % (IgA) und 96,3 % (IgG1) auf. Demgegenüber wies der ELISA zum Nachweis von spezifischem IgG im Blutserum bei einer Spezifität von 100 % nur eine Sensitivität von 81,5 % auf. Die sehr gute Reproduzierbarkeit der Tests wurde durch Intra-Assay-Variationen von 6,08 % für den Nachweis von IgA im Milchserum und 7,20 % für IgG1 sowie durch die geringe Inter-Assay-Variation von 6,32 % (IgA) und 9,74 % (IgG1) belegt. Der Einsatz dieser Testsysteme bei der Sanierung eines hochgradig mit P. zopfii infizierten Milchviehbestandes zeigte, dass die serologische Diagnostik dem bisher gebräuchlichen kulturellen Erregernachweis bei der Identifikation intermittierender Erregerausscheider überlegen ist. Es wurde deutlich, dass 70,5% der infizierten Tiere die Erreger über einen Zeitraum von 12 Monaten permanent ausschieden und mindestens weitere 4,9 %, wahrscheinlich jedoch wesentlich mehr, dieser infizierten Tiere intermittierende Erregerausscheider waren. Somit scheint der serologische Erregernachweis für die Diagnostik der Protothekenmastitis des Rindes besser geeignet zu sein als die kulturelle Diagnostik. Dabei wurde die höchste Sensitivität durch die Kombination des Nachweises von spezifischem IgA und IgG1 im Milchserum erzielt. / Protothecosis is a severe, often endemic mastitis in cattle caused by colorless algae of the genus Prototheca. Only little and insufficient knowledge about the organism itself, and the host immune response to this infection existed. Therefore, the aim of this thesis was to characterize the local and systemic immune response and the possible elimination or persistence of the pathogen in the host. To gain more information on the specific immune response, different clinical stages of infection were characterized serologically, culturally, and by determination of the number of the somatic cells in milk. Three different ELISA systems were developed, which were also examined for their diagnostic application potential. For the investigations, a dairy herd highly infected with Prototheca zopfii and severe clinical manifestation of protothecal mastitis was used. The ELISA was evaluated using serum and whey from animals with different clinical stages of infection. As antibody isotypes, IgG in serum, and IgA and IgG1 in whey were used. In addition, different isolates of P. zopfii were biochemically, serologically, and genetically examined in order to allow a differentiation of individual isolates within the species P. zopfii. The biochemical, serological and genetic investigations allowed a clear differentiation of the three known Variants of P. zopfii. All examined mastitis isolates could be assigned to variant II of P. zopfii. Therefore, it can be concluded that this variant has a particular epidemiological significance in the etiology of bovine protothecal mastitis. The serological investigations showed high antibody activities during acute and chronic stage of infection. The antibody activity was low in chronically infected, but presently cultural negative animals and also in uninfected animals. A strong correlation was observed between whey IgA and whey IgG1 antibody activity and the count of somatic cells in milk. Whereas, only a weak correlation exists to the number of algae cells excreted with the milk. A sensitivity of 96 % and a specificity of 94 % were calculated for the ELISA based on IgA levels. The ELISA for detection of specific IgG1 in whey shows a sensitivity of 92,6 % and a specificity of 96,3 %. Intra-assay and interassay variations were calculated to be at 6.08 % and 6.32 %, respectively. Based on these data, these ELISAs are suitable for discrimination between infected and uninfected animals, and might therefore be used for the screening of affected herds. When used in the remediation of a high-grade infected dairy herd the serological showed clear advantages in the identification of intermittent shedders. By culturing of Prototheca from milk, it was shown that 70.5% of the infected animals were permanent shedders, whereas 4.9 % were intermittent shedders. Since intermittent shedders could be clearly identified serologically, but might not be recognized by culturing, it can be assumed that serological diagnostics is more suitable for the identification of inapparently infected, intermittent shedders.
486

Multiplex flow cytometric assays for markers of inflammation : development and application in bovine samples /

Dernfalk, Johanna, January 2008 (has links) (PDF)
Diss. (sammanfattning) Uppsala : Sveriges lantbruksuniversitet, 2008. / Härtill 4 uppsatser.
487

Identification d'un moyen de lutte alternatif contre les mammites : synthèse, caractérisation et évaluation de l'activité antibactérienne in vitro d'huile de tournesol ozonée / Identification of an alternative mean of fight against mastitis : synthesis, characterization and evaluation of the in vitro antibacterial activity of ozonized sunflower oil

Moureu, Sophie 04 December 2015 (has links)
La mammite est une inflammation de la mamelle, le plus souvent, en réponse à une invasion d’origine bactérienne. L’utilisation d’antibiotiques pour le traitement de cette pathologie n’est pas la solution idéale. Outre les problèmes engendrés pour la qualité du lait, l’apparition de résistance et l’inefficacité des traitements nécessitent de développer des méthodes alternatives. L’objectif de ces travaux de thèse était de vérifier si l’utilisation d’huile de tournesol ozonée comme moyen de lutte alternatif contre les mammites est envisageable. Dans un premier temps, l’effet des conditions d’ozonation sur la composition et sur l’activité antibactérienne de l’huile ozonée a été étudié pour déterminer les conditions optimales de synthèse d’un agent antibactérien. Les résultats ont montré que l’ajout d’eau et l’augmentation de la durée de la réaction permettaient l’obtention de valeurs d’indice de peroxyde plus élevées et d’une meilleure activité antibactérienne mettant en évidence la relation existant entre ces deux paramètres. Par la suite, l’activité antibactérienne d’huile de tournesol ozonée a été évaluée in vitro sur 59 espèces bactériennes isolées de cas déclarés de mammites chez des brebis. Le produit testé a prouvé son efficacité contre toutes les souches étudiées avec des concentrations minimales inhibitrices de croissance comprises entre 0,625 et 20 mg/mL. L’homologation de l’huile de tournesol ozonée comme préparation vétérinaire requiert d’avoir des données sur sa stabilité thermique et d’identifier les molécules actives. Les travaux menés ont montré que la composition de l’huile de tournesol ozonée stockée à −20 °C ou à +4 °C n’évoluait pas pendant une durée d’un an. Au contraire, des températures de stockage plus élevées entrainaient rapidement une diminution de l’indice de peroxyde et une augmentation de l’acidité. Cependant, ces modifications n’ont pas eu d’effet sur l’activité antibactérienne qui a gardé une valeur constante. Ces observations ont permis d’émettre des hypothèses sur l’identité des molécules actives. L’activité antibactérienne des huiles ozonées serait due à la présence d’ozonides, d’hydroperoxydes et d’acides nonanoïque et azélaïque. L’étude de la réaction d’ozonolyse sur un composé modèle, l’oléate de méthyle, a permis d’affiner ces hypothèses. En effet, l’activité antibactérienne spécifique de différentes fractions obtenues après purification d’oléate de méthyle ozoné a été évaluée. Toutefois, les ozonides purifiés et caractérisés par RMN n’ont pas montré d’activité dans la gamme de concentration testée. L’activité antibactérienne de l’huile de tournesol ozonée peut donc être attribuée aux hydroperoxydes, aux aldéhydes et aux acides carboxyliques à chaines courtes. / Mastitis is an inflammation of the udder, usually in response to a bacterial invasion. The use of antibiotics for the treatment of this disease is not the ideal solution. In addition to the problems caused to the quality of milk, the development of resistance and ineffective treatments require to focus on alternative methods. The aim of this work was to verify if the use of ozonized sunflower oil as an alternative means of fight against mastitis could be possible. Firstly, the effect of the ozonation conditions on the composition and the antibacterial activity of ozonized oils was studied to determine the optimum conditions for the synthesis of an antibacterial agent. The results showed that the addition of water and increasing the duration of the reaction allowed to obtain higher peroxide index values and improved antibacterial activity highlighting the relationship between these two parameters. Afterwards, the antibacterial activity of ozonized sunflower oil was assessed in vitro against 59 bacterial species isolated from reported cases of mastitis in ewes. The tested product has proved its efficiency against all the strains studied with minimum inhibitory concentrations between 0.625 and 20 mg/mL. The registration of ozonized sunflower oil as a veterinary preparation requires to obtain data on its thermal stability and to identify the active molecules. The work carried out has shown that the composition of ozonized sunflower oil stored at −20 °C or +4 °C did not evolve for a period of one year. On the contrary, higher storage temperatures quickly led to a decrease of the peroxide index and an increase in acidity. However, these changes had no effect on the antibacterial activity that kept a constant value. These observations allowed speculating on the identity of active molecules. The antibacterial activity of ozonized oils could be due to the presence of ozonides, hydroperoxides and nonanoic acid and azelaic acid. The study of the ozonolysis reaction on a model compound, methyl oleate, helped to refine these assumptions. Indeed, specific antibacterial activity of various fractions obtained after purification of ozonized methyl oleate was evaluated. However, purified ozonides, characterized by NMR, showed no activity in the tested concentration range. The antibacterial activity of ozonized sunflower oil can therefore be attributed to hydroperoxides, aldehydes and short chain carboxylic acids
488

Estudo genético e quantitativo da contagem de células somáticas em bubalinos leiteiros

Mendoza-Sánchez, Geovanny [UNESP] 05 November 2007 (has links) (PDF)
Made available in DSpace on 2014-06-11T19:32:17Z (GMT). No. of bitstreams: 0 Previous issue date: 2007-11-05Bitstream added on 2014-06-13T19:02:48Z : No. of bitstreams: 1 mendozasanchez_g_dr_jabo.pdf: 284774 bytes, checksum: 92c1507cf74421e8e38247e70aded393 (MD5) / Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) / Universidade Estadual Paulista (UNESP) / Considerando-se que a contagem de células somáticas (CCS) de amostras de leite é um valioso indicador da saúde do úbere de búfalas, foi desenvolvido este trabalho com o objetivo de estimar a relação existente entre a CCS e a produção de leite (PL). Foram analisadas informações de 9404 amostras de controles de CCS e PL, referentes a 2198 lactações de animais da raça Murrah com idades entre 2 e 15 anos, filhas de 187 reprodutores, que ocorreram entre os anos 1997 e 2005. Para quantificar as perdas de PL em relação à CCS, nas análises de variância para a variável PL, foram incluídos no modelo os efeitos fixos de fazenda, ordem e ano de parto e estação do parto o escore da contagem de células somáticas (ECCS) como covariável, o efeito de animal dentro da fazenda foi considerado como aleatório. Para a estimação de parâmetros genéticos para a CCS, utilizaram-se “test day models”, a média da contagem de células somáticas na lactação (CCSt270) e a produção de leite aos 270 dias (PL270); os componentes de (co) variância foram estimados usando método de máxima verossimilhança restrita. A CCS de cada mês da lactação foi considerada como uma característica distinta, em análises uni e bicaracterísticas, o modelo incluiu como efeitos aleatórios, o genético aditivo direto e de ambiente permanente e residual. Além disso, foram considerados como efeitos fixos: grupo de contemporâneos, número de controle e idade da vaca ao parto como covariável (efeito linear e quadrático). Para a CCSt nos diferentes meses, os grupos de contemporâneos foram definidos como... / Considering that the somatic cells count (SCC) of samples of milk is a valuable indicator of the health of the buffaloes’ udder, this work was developed with the objective of estimating the relationship between SCC and milk yield (MY). Information on 9404 SCC and MY controls were analyzed. Data contained 2198 lactations of Murrah animals aging between 2 and 15 years, daughters of 187 sires, from 1997 and 2005. To quantify the decreases of MY in relation to SCC, the analyses of variance for the variable MY, included in the model a random animal effect nested in farm and the fixed effects of farm, order and year of parity and season of parity, somatic cells count score (SCCE) as covariate. For estimating genetic parameters for SCC, “test day models were used. For average of somatic cells count in the lactation (SCCt270) and milk yield to 270 days (MY270); the (co) variance components were estimated using Restricted Maximum Likelihood (MTDFREML). SCCs of every month of lactation were considered as different traits in single and double trait analyses. The model included genetic additive, permanent environmental (for SCCt270 and for MY270) and residual random effects. Other fixed effects were: contemporary group; control number and age of cow at parity as a covariate (linear and quadratic effects). For CCSt, contemporary groups were defined as flock-year-month of the control, and for SCCt270 and MY270 as herd-year- season of the parity. x It was found that all effects influenced the expression of SCCE. For first parity females, no relationship between MY and SCC was found. The results indicated that the largest decreases were observed in females with more than one parity. This category... (Complete abstract click electronic access below)
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Impacto da mentalidade do produtor e do engajamento dos funcionários sobre a qualidade do leite / Farmer mindset and employees engagement impact on milk quality

Larissa Nazareth de Freitas 23 September 2016 (has links)
A mastite é uma das principais doenças enfrentadas por produtores de leite do mundo todo. Um dos indicadores que está diretamente relacionado com a doença no rebanho é a contagem de células somáticas (CCS). Estudos recentes mostram que um dos fatores de risco associados à mastite é o homem. Isto é, fatores relacionados às práticas de manejo, gestão da propriedade e às características pessoais do produtor, como personalidade, atitude, crenças, intenções, habilidades, conhecimentos e outras são importantes, além do engajamento dos funcionários. Dessa forma, entender a influência do homem é fundamental para o controle e a prevenção da mastite. O objetivo deste trabalho foi i) verificar se as motivações e barreiras percebidas pelo produtor rural podem explicar a variação da (CCS) do tanque em fazendas de leite, ii) avaliar a mentalidade do produtor de leite com relação ao futuro do próprio negócio e, iii) se as necessidades dos funcionários de fazendas produtoras de leite estão sendo atendidas. Para isso, um estudo foi conduzido em 75 propriedades de leite da região sul do Brasil. A coleta de dados foi realizada por meio de entrevistas com os produtores e funcionários, utilizando um questionário composto por perguntas abertas e com respostas na escala Likert. Todos os questionários foram aplicados pelo mesmo pesquisador. Para o estudo da mentalidade do produtor foi utilizado o Modelo Comportamental Fogg (MCF) e, para o estudo do engajamento dos funcionários, foi utilizada a Teoria de Motivação de Maslow. Na análise estatística foram utilizados os modelos de equações estruturais e análises descritivas. Pelos resultados encontrados é possível concluir que a variação da CCS do tanque é explicada pelas motivações e barreiras percebidas pelos produtores, ou ainda, que o Modelo Comportamental Fogg (MCF) pode ser usado para explicar a influência do homem sobre a mastite. Além disso, é possível concluir que os produtores de leite não possuem mentalidade positiva com relação ao futuro do negócio e estão desmotivados com a atividade leiteira. Com relação aos funcionários, estes não estão engajados e existe uma grande barreira de comunicação entre produtor e funcionário, pois o produtor de leite não sabe o que o seu funcionário valoriza. Por fim, este estudo permite concluir que, empresas de consultoria que trabalham com a melhoria da qualidade do leite, deveriam focar também no fator humano através do estudo da mentalidade do produtor e do engajamento dos funcionários. / Mastitis is a major disease faced by dairy farmers worldwide. One of the indicators directly related to the prevalence of the disease in the herd is the bulk tank somatic cell count (BTSCC). Recent studies showed that one of the risk factors associated with mastitis is the human factor. That is, factors related to management practices, farm management and personal characteristics of the farmer, such as personality, attitude, beliefs, intentions, skills, knowledge and others are important, besides to employee\'s engagement. Therefore, to understand the influence of humans is fundamental to control and prevent the disease. The main goal of this study was i) to determine whether the motivations and barriers perceived by farmers can explain the variation in the BTSCC, ii) to evaluate the farmer mindset about the business future and, iii) if the needs of dairy farms employees are being met. Thus, a study was conducted at 75 dairy farms in southern Brazil. Data collection was conducted through interviews with farmers end employees using a survey based on open questions and Likert scale answers. All surveys were given by the same researcher. Fogg Behavioral Model (FBM) was used to study the farmer mindset and Maslow\'s Motivation Theory was used to study employee\'s engagement. In statistical analysis, structural equation models and descriptive analyzes were used. Through the results found is possible to conclude that variations in BTSCC can be explained by the motivations and barriers perceived by farmers and that the Fogg Behavioral Model (FBM) used in this study can be used to explain the influence of human behaviors towards mastitis control. In addition, it is possible to conclude that dairy farmers in the study area have no positive mindset regarding the company\'s future and are unmotivated with the dairy business. Regarding the employees, they are unmotivated and there is a barrier of communication between the farmer and the employee, because the farmer does not know what her or his employees most valorize. Finally, this study showed that consulting companies focused on improving the milk quality should also pay attention to the human factor through the study of farmer mindset and employee\'s engagement.
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Prevalência de Corynebacterium sp. no leite de vacas, sua correlação com o manejo de ordenha e contagem de células somáticas / Prevalence of Corynebacterium sp. in the milk cows, their relationship with milking pratices and somatic cells count

Dambrós, Dayane 09 March 2012 (has links)
Made available in DSpace on 2016-12-08T16:24:10Z (GMT). No. of bitstreams: 1 PGCA12MA087.pdf: 1147805 bytes, checksum: 749e6e38b1399033aef2801d2ef1b25f (MD5) Previous issue date: 2012-03-09 / The bovine mastitis is a disease that causes more losses in dairy farming, significantly reducing the production and milk quality. A causative agent of mastitis is the Corynebacterium sp. , especially the specie Corynebacterium bovis, but their role in intramammary infection is not yet defined, since some studies consider this agent, a minor pathogen of the mammary gland, causing no change in production and composition milk, though others, realize the large capacity of Corynebacterium sp. in causing mastitis, placing it as a risk factor for the development of the activity. Meet the microbiological profile of milk samples, the specific action of the agents in the mammary gland and its effect on milk quality, are of great importance in mastitis control programs. This study aimed to determine the prevalence of Corynebacterium sp. n the milk of cows from dairy herds located in five Brazilian states and to correlate the presence of this agent with the management of the milking herd and the somatic cell count of bulk tank milk and milk of individual cows. We conducted a longitudinal study from January 2010 to July 2011, in dairy herds located in the states of SC, PR, RS, MG and PE, which were performed in four colletions (at six months intervals) of milk samples in each herd. A questionnaire was applied in each farm to obtain data and information on the practices of milking herds, such as teat disinfection and teat drying, which may influence the occurrence of mastitis by Corynebacterium sp. Of the 4949 milk samples analyzed, submitted to microbiological culture, 666 (13,46%) had isolation of Corynebacterium sp. Minas Gerais was the state with the highest pravelence off this agent (21,07%) compared to others states. Risk factors associated with the management of milking, such as teat disinfection before and after milking and dry cow treatment showed no statistically significant influence on the prevalence of Corynebacterium sp. in milk samples analyzed. The isolation of Corynebacterium sp. in milk samples did not affect the SCC of bulk tank milk of the herds, but in the CMT, the presence of this agent caused variations in the number of positive mammary quarters and the degree of score in their test. Therefore Corynebacterium sp. is a causative agent of mastitis of great relevance not only by the frequency of isolation observed in this study, but also by the effect of CMT in individual cows and consequently in the herd SCC / A mastite bovina é a enfermidade que mais causa prejuízos na pecuária leiteira, reduzindo, significativamente, a produção e qualidade do leite. Um dos agentes causadores da mastite é o Corynebacterium sp., principalmente a espécie Corynebacterium bovis, porém seu papel na infecção intramamária ainda não é definido, pois alguns estudos consideram este agente, um patógeno menor da glândula mamária, sem causar alteração da produção e composição do leite, entretanto outros, constatam a grande capacidade do Corynebacterium sp. em causar mastite, colocando-o como um fator restritivo para o desenvolvimento da atividade leiteira. Conhecer o perfil microbiológico de amostras de leite, a ação específica dos agentes na glândula mamária e seu efeito na qualidade do leite, são de grande relevância em programas de controle da mastite. Este estudo teve como objetivos determinar a prevalência de Corynebacterium sp. no leite de vacas de rebanhos leiteiros localizados em cinco estados brasileiros e, correlacionar a presença deste agente com o manejo de ordenha dos rebanhos e com a contagem de células somáticas do leite do tanque e do leite individual das vacas. Foi realizado um estudo longitudinal, de janeiro de 2010 a julho de 2011, em rebanhos leiteiros localizados nos estados de SC, PR, RS, MG e PE, nos quais foram realizadas quatro coletas (semestrais) de amostras de leite em cada rebanho. Foi aplicado um questionário, em cada propriedade, para obter dados e informações sobre o manejo de ordenha dos rebanhos, como a desinfecção pré e pós-ordenha, secagem dos tetos, que possam influenciar na ocorrência de mastite por Corynebacterium sp. Do total de 4949 amostras de leite analisadas, submetidas a cultura microbiológica, 666 (13,46%) apresentaram isolamento de Corynebacterium sp. Minas Gerais foi o estado que apresentou a maior prevalência deste agente (21,07%) comparado aos demais estados. Os fatores de risco associados ao manejo de ordenha das propriedades, como a desinfecção dos tetos pré e pós-ordenha e o tratamento de vaca seca não apresentaram influência estatística significativa na prevalência de Corynebacterium sp. nas amostras de leite analisadas. O isolamento de Corynebacterium sp nas amostras de leite não afetou a CCS do leite do tanque dos rebanhos, porém no CMT, a presença deste agente causou variações no número de quartos positivos e no grau de escore no respectivo teste. Portanto, Corynebacterium sp. é um agente causador de mastite de grande relevância, não só pela freqüência de isolamento observada no presente estudo, mas também pelo efeito no CMT individual das vacas e consequentemente na CCS do rebanho

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