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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.
121

Mastito sukėlėjų įtaka karvių pieno sudėčiai / The relationship between mastitis pathogens and milk composition

Mirošničenko, Virginija 05 March 2014 (has links)
Mastitas yra viena iš brangiausių ir dažniausiai pasitaikančių pieno ūkių problemų, kuri aktuali visam pasauliui. Ekonominiai nuostoliai patiriami kiekvieną dieną, dėl pieno kieko sumažėjimo, pieno kokybės suprastėjimo, didelių gydymo kaštų, mastitu sergančių karvių išbrokavimo. Pirmame etape buvo tiriamos „X“ pieninių galvijų bandos karvės; antrame etape - 8 Lietuvos pieninių galvijų ūkių karvės. Buvo nustatyti visų karvių mastito sukėlėjai ir išanalizuoti jų pieno sudėties ir somatinių ląstelių skaičiaus kontrolės duomenys. Pirmame tyrimo etape įvertinus mastito sukėlėjų paplitimą tirtoje pieninių galvijų bandoje nustatyta, kad labiausiai paplitę buvo Streptococcus spp (22,22 proc.) Antrame tyrimo etape tirtose Lietuvos pieninių galvijų bandose labiausiai paplitę mastito sukėlėjai - Streptococcus spp. - 23 proc. Tirtoje karvių bandoje didžiausias somatinių ląstelių skaičius buvo pieno mėginių karvių, kurioms buvo nustatyta Streptococcus spp. (D grupė) sukėlėjas – 3430 ± 305 tūkst./ml. Mažiausias pieno riebumo vidurkis nustatytas Staphylococcus spp. su Escherichia coli 3,38 ± 0,08 proc. Mažiausias baltymingumo vidurkis Staphilococcus aureus 3,1 ± 0,01 proc. Ir mažiausias laktozės vidurkis Streptococcus spp.4,1 ± 0,2 proc. (p<0,05). Tirtose Lietuvos pieninių galvijų bandose didžiausias SLS kiekis nustatytas piene karvių, kurių mėginiuose buvo Staphylococcus spp. su Enterococcus spp - jų vidutinis somatinių ląstelių skaičius buvo 3198 ± 255 tūkst./ml. Mažiausias pieno... [toliau žr. visą tekstą] / Bovine mastitis is the most prevalent and costly disease, affecting dairy farms worldwide. Economic losses associated with mastitis derive mainly from a decrease in milk production and to a lesser extent, from the culling of chronically infected cows, cost of veterinary treatment, and penalties on milk quality. The researches was carried out in 2011 – 2014 at State Laboratory “Pieno Tyrimai”, at the Department of Animal Breeding of the Veterinary Academy of the Lithuanian University of Health Sciences and in dairy farm. At the first phase there was investigated „X“ dairy cows herd. And at the second phase there was investigated Lithuanian dairy cow’s herds. In both have been investigated cow’s mastitis pathogens and analyzed cow’s milk structure changes. The biggest part of the cows in tested cows herd was found to be infected with Streptococcus spp. (22.22 proc.) and in Lithuanian dairy cows herds - Streptococcus spp. (23 proc.). The most elevated somatic cells count was determined in tested dairy cows infected with Streptococcus spp. (D group) (3430 ± 305 thousands/ml.). The most decrease milk fats was determined to Staphylococcus spp. and E. coli (3.38 ± 0.08 proc.). The most decreased milk proteins to - S. aureus (3.1 ± 0.01 proc.). And most decreased milk lactose to - Streptococcus spp.4.1 ± 0.2 proc. (p<0.05). The most elevated somatic cells count was determined, in Lithuanian dairy cows herds, infected with Staphylococcus spp. and Enterococcus spp. (3198 ± 255... [to full text]
122

Peripartale hämatologische und klinisch-chemische Blutuntersuchungen zur Frühdiagnostik der Dislocatio abomasi, Gebärparese, Retentio secundinarum und Mastitis bei Milchkühen / Peripartal screenings of haematological and blood chemical parameters for the early diagnosis of abomasal displacement, milk fever, retained placenta and mastitis in dairy cows

Schwartau, Katja 14 February 2012 (has links) (PDF)
Zusammenfassung Katja Schwartau Peripartale hämatologische und klinisch-chemische Blutuntersuchungen zur Frühdiagnostik der Dislocatio abomasi, Gebärparese, Retentio secundinarum und Mastitis bei Milchkühen Medizinische Tierklinik der Veterinärmedizinischen Fakultät der Universität Leipzig Eingereicht im Mai 2011 Bibliographische Angaben 94 Seiten, 22 Abbildungen, 19 Tabellen, 210 Literaturangaben, Schlüsselwörter: Labmagenverlagerung, Gebärparese, Retentio secundinarum, Mastitis, Kuh Produktionskrankheiten haben in den letzten Jahren immer mehr an Bedeutung gewonnen. Diese leistungsassoziierten Bestandserkrankungen tragen wesentlich zur kurzen Nutzungsdauer von ca. 2,5 Jahren der Milchkühe bei. Es ist deshalb besonders wichtig, ihre Prophylaxe einschließlich der Früherkennung in den Vordergrund zu stellen. In der vorliegenden Untersuchung wurden deshalb frühdiagnostische Möglichkeiten der LMV (Labmagenverlagerung), GP (Gebärparese), Retentio sec. (Retentio secundinarum) und Mastitis geprüft. Des Weiteren wurden die Kühe in einer Gruppe „krank“ und einer Gruppe „gesund“ gegenübergestellt, um durch Stoffwechselabweichungen generell subklinische Veränderungen zu erkennen, die Hinweise auf bevorstehende Erkrankungen geben. Besondere Beachtung fand für die Bewertung des Erkrankungsrisikos die odds ratio. In die Untersuchung wurden insgesamt 398 Schwarzbunte Kühe einbezogen. 49 Tiere waren an einer LMV, 121 Tiere an einer GP, 131 an einer Retentio sec. und 119 Tiere an einer Mastitis erkrankt. Im Gruppenvergleich gesund/krank wurden 347 erkrankte Kühe mit 51 klinisch gesunden Tieren verglichen. Es wurden bei allen Kühen 14-7 d a.p. (Tage ante partum) und 3 d p.p. (Tage post partum) Blutproben entnommen. Es wurden Parameter des Energie-, Fett- und Leberstoffwechsels (FFS [Freie Fettsäuren], BHB [ß-0H-Butyrat], Cholesterol, Glucose, Insulin, AST [Aspartat-Amino-Transferase], Bilirubin), des Eiweißstoffwechsels (Albumin, Haptoglobin, TP [Gesamt-Eiweiß], Harnstoff, Kreatinin) und der Leukozyten sowie des Mineralstoffwechsels (Na [Natrium], K [Kalium], Cl [Chlorid], Ca [Calcium], Pi [anorganisches Phosphat], AP [Alkalische Phosphatase]) und der CK [Creatinkinase] bestimmt und mit gesunden Kühen verglichen. 92 Auf das Risiko einer LMV weisen a.p. besonders Konzentrationssteigerungen des Haptoglobins hin. Aber auch die Mediane der Glucose und der AP liegen außerhalb des Referenzbereichs bei Tieren, die später an einer LMV erkranken. Drei d p.p. kommen signifikante Konzentrationsanstiege der FFS, des BHB und des Bilirubin sowie signifikante Konzentrationsabnahmen des Insulin (odds ratio 8,43) bis unter den Normbereich hinzu. Die Aktivitäten der AP und auch die Konzentrationen von Cholesterol und Ca bleiben ebenfalls unter dem Normbereich. Die Mediane der AST-Aktivität und der Haptoglobinkonzentration liegen oberhalb des Referenzbereichs. Auf das Risiko einer GP weisen a.p. und p.p die verminderte AP-Aktivität sowie Konzentrationsanstiege der FFS (odds ratio 1,78) hin. Drei d p.p ergänzen die Konzentrationen des BHB, des Bilirubins und des Haptoglobins (odds ratio 4,59) oberhalb der Referenzbereiche die Veränderungen. Der Median der Insulinkonzentration liegt 3 d p.p. unter dem Referenzbereich. Einer Retentio sec. gehen erhöhte Glucosekonzentrationen a.p. voraus. Der Median der AP-Aktivitäten liegt schon a.p. unter dem Normbereich. Drei d p.p. unterscheidet er sich signifikant von Kühen ohne Retentio sec. Hinweise auf Mastitiden liefern p.p. die Konzentrationen des BHB (odds ratio 1,78). Die Mediane der Glucosekonzentrationen liegen a.p. oberhalb und die der AP-Aktivitäten unterhalb der Referenzbereiche. Drei d p.p. kommen Steigerungen der Haptoglobin-, Glucose- und Bilirubinkonzentrationen sowie Aktivitätssteigerungen der AST bis über den Normbereich hinzu. Als Besonderheit liegen die Ca- und Pi-Konzentrationen aufgrund des geringeren Abflusses bei einer verminderten Milchleistung signifikant über denen der gesunden Kühe. Für die Entstehung postpartaler Erkrankungen generell verdienen die signifikanten Konzentrationssteigerungen der Glucose sowie die Abnahme der AP-Aktivität besondere Beachtung. Das BHB (odds ratio 1,92 a.p.) und die CK (odds ratio 2,17 a.p.) weisen auf ein erhöhtes Krankheitsrisiko hin. Drei d p.p. kommen zu den Veränderungen dieser Parameter noch signifikante Konzentrations- bzw. Aktivitätssteigerungen der FFS, des BHB, der CK, des Bilirubins, der AST und des Haptoglobins (odds ratio 4,61) sowie erniedrigte Ca-Konzentrationen hinzu. Die Untersuchungen haben gezeigt, dass a.p. generell Abweichungen des Energiestoffwechsels und im Besonderen gesteigerte Glucosekonzentrationen sowie erniedrigte AP-Aktivitäten ein erhöhtes Risiko für postpartale Erkrankungen anzeigen. Höhere Aussagekraft besitzen Kontrollen am 3. d p.p. mit den Parametern Insulin (odds ratio 8,4), FFS, BHB und Haptoglobin (odds ratio 4,61), deren Konzentrationen gegenüber gesunden Kühen signifikant abweichen. Ähnlich gute Eignung zeigen, Bilirubin, AST und Ca.
123

A study of the public health significance of bovine mastitis a thesis submitted in partial fulfillment ... Master of Science in Public Health ... /

Coogan, Charles P. January 1900 (has links)
Thesis (M.S.P.H.)--University of Michigan, 1939.
124

A study of the public health significance of bovine mastitis a thesis submitted in partial fulfillment ... Master of Science in Public Health ... /

Coogan, Charles P. January 1900 (has links)
Thesis (M.S.P.H.)--University of Michigan, 1939.
125

Expressão gênica diferencial em úbere extracorpóreo de vacas mestiças Holandês-Zebu infectado por Streptococcus agalactiae / Differential gene expression in mamary tissue extracorpóreo of Holandês-Zebu cows infected by Streptococcus agalactiae

Sbardella, Ana Paula [UNESP] 29 July 2016 (has links)
Submitted by ANA PAULA SBARDELLA null (paulasbardella@gmail.com) on 2016-08-30T12:48:56Z No. of bitstreams: 1 ANAPAULASBARDELLA_GENÉTICA_E_MELHORAMENTO_ANIMAL_MESTRADO_VERSÃO_FINAL.pdf: 2368521 bytes, checksum: c62c877ae578820d87db27a37651a178 (MD5) / Approved for entry into archive by Ana Paula Grisoto (grisotoana@reitoria.unesp.br) on 2016-08-31T12:58:56Z (GMT) No. of bitstreams: 1 sbardella_ap_me_jabo.pdf: 2368521 bytes, checksum: c62c877ae578820d87db27a37651a178 (MD5) / Made available in DSpace on 2016-08-31T12:58:56Z (GMT). No. of bitstreams: 1 sbardella_ap_me_jabo.pdf: 2368521 bytes, checksum: c62c877ae578820d87db27a37651a178 (MD5) Previous issue date: 2016-07-29 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A mastite é responsável por grandes perdas econômicas na bovinocultura leiteira e necessita de maior compreensão de suas bases genéticas para que métodos de melhoramento genético possam ser desenvolvidos. Neste sentido, estudos de expressão gênica têm sido empregados. Portanto, os objetivos deste trabalho foram: 1. Detectar, por meio de três métodos computacionais distintos, a expressão gênica diferencial de dados obtidos por sequenciamento de RNA extraído de glândula mamária mantida em um sistema extracorpóreo de bovinos de leite mestiços Holandês-Zebu e infectada experimentalmente com Streptococcus agalactiae; 2. Estudar o perfil de expressão do total de genes identificados e aqueles comuns aos três métodos relacionados ao desenvolvimento da mastite, a fim de contribuir para melhor entendimento de processos biológicos, de componente celular e função molecular e vias biológicas envolvidas com a expressão desta característica. Quatro vacas foram abatidas e os úberes foram colhidos, perfundidos e inoculados com S. agalactiae. Para cada úbere, dois quartos foram inoculados (anterior esquerdo - AE; e posterior esquerdo - PE) e dois quartos foram utilizados como controle (anterior direito - AD; e posterior direito - PD). Biópsias foram feitas do tecido alveolar nos tempos 0 e 3 horas após a perfusão do tecido. O RNA das amostras foi extraído e sequenciado com a plataforma HiSeq2000 (Illumina). A partir das leituras obtidas os transcritos foram montados utilizando como referência a anotação do genoma bovino UMD 3.1 e então foram avaliadas quanto à sua expressão diferencial e funcionalidade. Métodos que assumem distribuição binomial negativa executados pelos métodos computacionais edgeR e baySeq e o método que assume distribuição beta binomial negativa executado pelo Cuffdiff, foram utilizados para análise de expressão gênica diferencial. Foram identificados 5.158 genes provenientes da união dos resultados obtidos com os três métodos computacionais. Esses genes foram investigados pela plataforma DAVID revelando o enriquecimento de termos de ontologia gênica, dentre os quais destacaram-se os processos de resposta a estímulos, sistema imune e processos apoptóticos. O perfil de genes diferencialmente expressos em amostras afetadas foi associado com a diferenciação, proliferação, migração e apoptose celular, desempenhando importante papel no local da inflamação por células do sistema imune, além de ativar vias de sinalização relacionadas ao sistema imune que são importantes nas primeiras três horas de infecção. Foram identificados apenas 122 genes com expressão diferencial em comum pelos três métodos utilizados. A restrição causada pelo uso da intersecção dos resultados obtidos com os três métodos não se mostrou adequada para realizar o enriquecimento funcional pois muitos genes de interesse foram desconsiderados e perdeu-se suporte estatístico nas análises de enriquecimento funcional. Assim, sugerimos que para esse tipo de estudo é mais adequado a utilização dos resultados de um dos métodos ou a união dos resultados dos três métodos. Este estudo permitiu maior entendimento das bases genéticas do desenvolvimento da mastite em úbere extracorpóreo de bovinos leiteiros mestiços holandês-Zebu, infectado experimentalmente por S. agalactiae, durante as primeiras horas de infecção. / Mastitis is responsible for huge economic losses in dairy cattle production which requires a better understanding of its genetic bases in order that genetic breeding methods could be developed. Therefore, some gene expression studies have been developed. The aims of this study were: 1. To detect, through three different computational methods, the differential gene expression data obtained by RNA sequencing from mammary glands of Holstein-Zebu crossbred dairy cattle, kept in an extracorporeal system and experimentally infected with Streptococcus agaclatiae; 2. To study the total gene expression profile and those genes common to the three methods, related with mastitis, in order to contribute to a better understanding of biological processes, cellular components, molecular functions and metabolic pathways related with the expression of this trait. Four cows were slaughtered and its udders were perfused and inoculated with S. agalactiae. For each udder, 2/4 were inoculated (front left - AE, and rear left - PE) and 2/4 were used as control (front right - AD, and rear right - PD). Biopsies were obtained from the alveolar tissue at 0 and 3 hours after the tissue perfusion. The RNA sample was extracted and sequenced with HiSeq 2000 platform (Illumina). From the reads obtained transcripts were assembled using as the reference the bovine genome annotation UMD 3.1, and then were evaluated for differential expression and functionality. Methods that assumes negative binomial distribution performed by edgeR and baySeq and the method that assumes beta negative binomial distribution performed by Cuffdiff were used for differential gene expression analysis. From the union of the results obtained with all computational methods, a total of 5,158 genes were identified. These genes were investigated by DAVID platform showing the enrichment of gene ontology terms, which were highlighted the response processes stimuli, immune response and apoptotic processes. The profile of differentially expressed genes identified in the affected samples was associated with differentiation, proliferation, migration and apoptosis, playing a major role in the inflammation site by immune system cells and in the activation of signaling pathways related to the immune system, which are important in the early three hours of infection. Only 122 differentially expressed genes were identified in common by the three methods. The restriction caused by the use of the intersection of the results obtained with the three methods was not interesting to perform functional enrichment analysis because there is loss of many interesting genes and the functional enrichment analysis has no statistical support. Thus, for this kind of study, we suggest that could be most appropriate the use of the results obtained with one method or the union of the results obtained with more than one method. This study allowed a better understanding of the genetic basis of mastitis developing in extracorporeal udder of Holstein-Zebu crossbred dairy cattle, during the early hours of experimentally infection by S. agalactiae.
126

Comparação entre a contagem de células somáticas obtidas de secreção láctea de vacas com mastite sub-clínica, antes e depois de tratamento homeopático / Comparison between somatic cell counts in milk samples from bovine cows with sub-clinical mastitis, before and after homeopathic treatment

Roberto Mangieri Junior 15 December 2005 (has links)
Objetivou-se neste trabalho, comparar se o tratamento homeopático eliminou ou não o agente causal das mastites subclinicas; se houve alteração na contagem de células somáticas (CCS) e a variação da produção láctea antes e depois do tratamento homeopático proposto. Utilizou-se 34 glândulas mamárias de 22 vacas que apresentavam mastite subclinica, CMT 2+ e 3+, pluríparas entre o terceiro e sexto me de lactação e entre a segunda e a quinta cria. Foram divididas em 2 grupos. O grupo teste-homeopatia recebeu 15 glóbulos do medicamento Phytolaca decandra 6 CH duas vezes ao dia,e o grupo controle recebeu 15 glóbulos inertes, duas vezes ao dia, por 15 dias consecutivos. Ao final do experimento, não houve diferença significativa entre as contagens de células somáticas da secreção láctea das glândulas quando comparadas antes e depois do tratamento homeopático, bem como quando comparou-se ambos os grupos. Porém, observou-se que a produção láctea dos animais tratados com remédio homeopático aumentou significativamente (P<0,05) em 2,5 kg/leite/dia em média. No grupo tratado com placebo não houve diferença significativa na produção láctea no mesmo período. / Mammary gland inflammatory process has been particularly frequent and important in dairy cattle and gives a lot of damage. Infectious mastitis is the most important injury either by economic or public health points of view. Identify the aggressor microorganism and somatic cells count (SCC) in milk are important tools to avail the sanitary conditions of the herd and how victim react against the aggressor. In clinical mastitis, the signs of the injury and resulting reaction of the organism who suffer the injury are evident, clear, so are seem signs and symptoms of inflammation. Otherwise, in sub-clinical mastitis, signs and symptoms of inflammations are not seen, and to realize it there are technical methods. In this case, the option was use as sub-clinical mastitis indicator the Tamis test (black ground cup) and the CMT (California Mastitis Test). Then, was chosen 22 cows that obtained score 2+ and 3+ on CMT test of each teat, between third and sixth months milking and second and fifth birth. They were separated into two groups. Homeopathy is a kind of therapy that has been recently used in animals with such satisfactory results. The conventional drugs have restricted use on organic production and in same cases are forbidden. In the start of this investigation, before the homeopathic treatment, was collected, from the each teat that had sub-clinical mastitis (CMT 2+ and 3+), two milk samples. One of then was sent to somatic cells count (SCC) and another to the microbiological laboratory to identify the microorganism. Milk production from each cow, were under control all time. Since this point the group called Test-homeopathy received the homeopathic medication Phytolacca decandra 6 ch, 15 pills twice a day, and the group called Control, received placebo, 15 pills twice a day, for both groups. At the end of 15 days of treatment, a new double collect of milk samples from each same teats were done. The samples were sent again to the microbiological laboratory to identify the microorganism implicated and to somatic cells counter (SCC) laboratory. The weight of milk production of each cow was controlled before and after treatment of each cow from both groups. At the end of research, there were no significant rates between somatic cells counts (SCC) of the milk when compared before and after homeopathic treatment, as well as when compared among both groups. But, it was observed that milk production of cows which received homeopathic treatment had an increase statistically significant (P<0,05) on 2,5 kg of milk/ day in media, and the group which received placebo there were no significant rates in milk productions in the same time.
127

Einfluss verschiedener bestandsspezifischer E. coli-Vakzinen auf die Eutergesundheit von Milchrindern

Heine, Manuela 26 November 2013 (has links)
Die Mastitis beim Milchrind hat eine große ökonomische Bedeutung, daher liegt derzeit ein Forschungsschwerpunkt auf der Aktivierung und Stabilisierung der körpereigenen Abwehr zur Bekämpfung von Euterentzündungen. Besonders im peripartalen Zeitraum liegt eine Prädisposition für Infektionen vor, da eine physiologische Abwehrschwäche besteht. Daher erscheint die Förderung der Bildung von Antikörpern durch Impfungen sinnvoll. Getestet wurde der Einfluss von bestandsspezifischen E. coli-Vakzinen auf das Immunsystem, das Erregervorkommen in der Milch und die Eutergesundheit. Differenziert wurden Impfstoffe, die einerseits aus den Originalkulturen der antigenen Erreger (sogenannte large colony variants, LCV) oder aber aus den kleineren, intrazellulär persistierenden Erregern (small colony variants, SCV) hergestellt wurden. Letztlich zeigte sich bei Anwendung der Vakzinen an Milchrindern kein Unterschied zwischen LCV und SCV, bei beiden Impfstoffen war eine vakzinationsbedingte deutliche Steigerung der Antikörpertiter, welche einen Einfluss auf Erregervorkommen und Eutergesundheit hatte, erkennbar.
128

Application of soluble CD14 and a trivalent vaccine to prevent mastitis caused by Escherichia coli and Staphylococcus aureus

Lee, Jai-Wei, 1970- January 2003 (has links)
No description available.
129

Identification and characterization of differentially expressed genes in response to Escherichia coli and Staphylococcus aureus in bovine mammary epithelial cells and mammary gland

Roy, Mélanie. January 2006 (has links)
No description available.
130

Effect of selective dry cow therapy on udder health of US dairy herds

Torres, Audrey H. 26 June 2007 (has links)
No description available.

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