Ziel dieser epidemiologischen Studie war es, das Vorkommen und das Artenspektrum von Eimeria spp. sowie den Infektionsverlauf in zwei konventionell geführten landwirtschaftlichen Betrieben in Schleswig-Holstein unter Feldbedingungen zu untersuchen und eine Behandlungsstrategie abzuleiten.

On two farms in a two-year period (spring 2005,autumn 2005, spring 2006, autumn 2006) calves faecal samples from the rectum or from the floor were obtained for parasitologic examination. A total of 560 samples from 209 calves were examined using the floatation method in Sheather's sugar solution. In positive samples the presence of Giardia intestinalis cysts, Cryptosporidium parvum, C. andersoni and Eimeria spp. oocysts was found. The infection by C. parvum was the highest from the 1st to the 3rd week and the infection by C. andersoni was the highest from the 7th to the 8th week of the calves age. In both breedings Coccidia Eimeria spp. was the most diagnosed, followed by G. intestinalis. With calves bred in stables by two a higher probability of parasitic infection was detected (46,9 %) compared to breeding of calves in outer individual boxes (17,6). The excrements of the calves were mainly of pasty or even of mushy consistence and the prevalence of the parasites was in most cases diagnosed in single infections.

Doenças, como a enterite necrótica aviária (NE), têm se tornado reemergentes em função não apenas do sistema de criação intensivo de frangos de corte atualmente em uso, como também da restrição imposta ao uso dos aditivos antimicrobianos por diversos países, dentre os quais, aqueles da União Européia. A NE é uma doença que acomete aves de produção e seu agente etiológico primário é o Clostridium perfringens tipo A. Pouco se conhece a respeito dos mecanismos pelos quais o estresse modula o desenvolvimento da NE. O presente trabalho foi realizado para avaliar os efeitos do estresse por calor sobre o desenvolvimento da NE em frangos de corte. Empregou-se, para tal, modelos experimentais de NE em que se usou infecção isolada por C. perfringens e/ou em co-infecção com Eimeria spp. O estresse por calor foi aplicado de forma contínua ou intermitente em longo prazo. Foram propostos sete experimentos; em cinco deles os animais foram criados em câmaras isoladoras e, nos dois restantes, em galpões. Foram feitas avaliações da imunidade sistêmica, de órgãos linfoides secundários e do intestino delgado para determinar os efeitos imunomodulatórios da infecção e/ou do estresse por calor. Para caracterização dos efeitos neuroimunes, fizemos uma análise integrada dos achados imunes, de atividade do Sistema Nervoso Central e/ou de ativação do eixo hipotálamo-hipófise-adrenal (HPA). Foram utilizadas medidas quantitativas e semiquantitativas para avaliar os diferentes graus de lesão tecidual decorrentes do processo infeccioso e/ou parasitário com ou sem estresse por calor. Para analisar os efeitos do estresse no processo infeccioso/parasitário empregamos, também, cultivos microbiológicos e técnicas usadas para determinação da proliferação do C. perfringens e da Eimeria spp. Os resultados mostraram que o estresse por calor: reduziu a inflamação intestinal e o dano tecidual em modelo de NE empregando infecção isolada por C. perfringens preparada em caldo tioglicolato; reduziu a formação de centros germinais esplênicos e intestinais com consequente modulação da produção de imunoglobulinas séricas e secretórias; ativou núcleos do SNC relacionados á atividade do eixo HPA; ativou o eixo cérebro-intestinal; diminuiu a infecção intestinal por Eimeria spp., com consequente redução do desenvolvimento da NE e da lesão tecidual dela resultante; modulou a atividade de sistemas de neurotransmissão central relacionados com o comportamento das aves e ativação do eixo HPA; alterou o perfil neuroquímico cerebral quando em associação com a NE; facilitou o desenvolvimento da infecção por C. perfringens em animais não desafiados por fatores predisponentes da NE; reduziu a lesão tecidual no modelo de co-infecção por C. perfringens e Eimeria spp.; modulou o balanço de citocinas para um padrão Th2 no intestino dos animais infectados ou não; alterou as subpopulações de linfócitos esplênicos e circulantes, bem como a função proliferativa destas células e a resposta das mesmas à expressão de citocinas. Desta forma, concluímos que o estresse por calor e/ou inflamação intestinal de origem infecciosa ou química ativam o eixo HPA por mecanismo que envolve o eixo cérebro-intestinal, reduzindo os sinais clínicos da NE por interferir na patogênese do C. perfringens e da Eimeria spp / Diseases such as necrotic enteritis (NE) are coming back not only as a consequence of the intensive farming procedures now being used but also as a consequence of the restrictions imposed by the European Union countries to the use of antimicrobials as feed additives. NE is a disease that affects poultry production; its primary etiologic agent is Clostridium perfringens type A. Little is known about the mechanisms by which stress modulates the development of NE. Thus, to evaluate the effects of heat stress on NE development, sevenstudies were done using experimental models of NE that used C. perfringens infection per se or in combination with Eimeria spp. Heat stress was used throughout the experiments, being applied continuously or intermittently but always for long-term. Five experiments were performed using animals reared in isolator chambers and two others employing animals reared in sheds. Evaluations of systemic immunity, secondary lymphoid organs and small intestine portions were used to determine the immunomodulatory effects of the infections and/or of the heat stress. Neuroimmune effects were assessed using an integrative approach of the observed immune, Central Nervous System (CNS) and/or hypothalamic-pituitary-adrenal (HPA) axis changes. Quantitative and semi-quantitative techniques were utilized to measure and compare the different degrees of tissue damage resulting from the infectious processes in the presence and absence of heat stress. Microbiological techniques were also used to determine C. perfringens and Eimeria spp. proliferations. Results showed that heat stress: reduced intestinal inflammation and tissue damage in the NE model that used C. perfringens together with thioglycolate broth culture medium intake; reduced the formation of splenic and intestinal germinal centers with subsequent production of serum and secretory immunoglobulins; activated some brain areas related to animals behavior and HPA axis activity; modified the brain-gut axis relationship during NE development; reduced Eimeria spp. infection leading to a subsequent reduction in the NE development and in the scores of tissue injury; together with NE, modified neuronal brain-amine systems activity and, as a consequence, changed animals behavior, HPA axis activity and brain amine systems fuction within some brain areas; predisposed the birds to C. perfringens infection in the presence or absence of NE inducing factors; reduced the tissue damages observed in the course of C. perfringens and Eimeria spp.co-infection; modulated cytokines to a Th2 pattern in animals infected or not; altered the splenic and peripheral blood lymphocytes subpopulations and, changed the proliferative function of immune cells and cytokine expression.Thus, we conclude that the heat stress and/or intestinal inflammation of infectious or chemical origin activate the HPA axis by a mechanism involving the brain-gut axis, reducing the clinical signs of NE by interfering in the pathogenesis of C. perfringens and Eimeria spp

Doenças, como a enterite necrótica aviária (NE), têm se tornado reemergentes em função não apenas do sistema de criação intensivo de frangos de corte atualmente em uso, como também da restrição imposta ao uso dos aditivos antimicrobianos por diversos países, dentre os quais, aqueles da União Européia. A NE é uma doença que acomete aves de produção e seu agente etiológico primário é o Clostridium perfringens tipo A. Pouco se conhece a respeito dos mecanismos pelos quais o estresse modula o desenvolvimento da NE. O presente trabalho foi realizado para avaliar os efeitos do estresse por calor sobre o desenvolvimento da NE em frangos de corte. Empregou-se, para tal, modelos experimentais de NE em que se usou infecção isolada por C. perfringens e/ou em co-infecção com Eimeria spp. O estresse por calor foi aplicado de forma contínua ou intermitente em longo prazo. Foram propostos sete experimentos; em cinco deles os animais foram criados em câmaras isoladoras e, nos dois restantes, em galpões. Foram feitas avaliações da imunidade sistêmica, de órgãos linfoides secundários e do intestino delgado para determinar os efeitos imunomodulatórios da infecção e/ou do estresse por calor. Para caracterização dos efeitos neuroimunes, fizemos uma análise integrada dos achados imunes, de atividade do Sistema Nervoso Central e/ou de ativação do eixo hipotálamo-hipófise-adrenal (HPA). Foram utilizadas medidas quantitativas e semiquantitativas para avaliar os diferentes graus de lesão tecidual decorrentes do processo infeccioso e/ou parasitário com ou sem estresse por calor. Para analisar os efeitos do estresse no processo infeccioso/parasitário empregamos, também, cultivos microbiológicos e técnicas usadas para determinação da proliferação do C. perfringens e da Eimeria spp. Os resultados mostraram que o estresse por calor: reduziu a inflamação intestinal e o dano tecidual em modelo de NE empregando infecção isolada por C. perfringens preparada em caldo tioglicolato; reduziu a formação de centros germinais esplênicos e intestinais com consequente modulação da produção de imunoglobulinas séricas e secretórias; ativou núcleos do SNC relacionados á atividade do eixo HPA; ativou o eixo cérebro-intestinal; diminuiu a infecção intestinal por Eimeria spp., com consequente redução do desenvolvimento da NE e da lesão tecidual dela resultante; modulou a atividade de sistemas de neurotransmissão central relacionados com o comportamento das aves e ativação do eixo HPA; alterou o perfil neuroquímico cerebral quando em associação com a NE; facilitou o desenvolvimento da infecção por C. perfringens em animais não desafiados por fatores predisponentes da NE; reduziu a lesão tecidual no modelo de co-infecção por C. perfringens e Eimeria spp.; modulou o balanço de citocinas para um padrão Th2 no intestino dos animais infectados ou não; alterou as subpopulações de linfócitos esplênicos e circulantes, bem como a função proliferativa destas células e a resposta das mesmas à expressão de citocinas. Desta forma, concluímos que o estresse por calor e/ou inflamação intestinal de origem infecciosa ou química ativam o eixo HPA por mecanismo que envolve o eixo cérebro-intestinal, reduzindo os sinais clínicos da NE por interferir na patogênese do C. perfringens e da Eimeria spp / Diseases such as necrotic enteritis (NE) are coming back not only as a consequence of the intensive farming procedures now being used but also as a consequence of the restrictions imposed by the European Union countries to the use of antimicrobials as feed additives. NE is a disease that affects poultry production; its primary etiologic agent is Clostridium perfringens type A. Little is known about the mechanisms by which stress modulates the development of NE. Thus, to evaluate the effects of heat stress on NE development, sevenstudies were done using experimental models of NE that used C. perfringens infection per se or in combination with Eimeria spp. Heat stress was used throughout the experiments, being applied continuously or intermittently but always for long-term. Five experiments were performed using animals reared in isolator chambers and two others employing animals reared in sheds. Evaluations of systemic immunity, secondary lymphoid organs and small intestine portions were used to determine the immunomodulatory effects of the infections and/or of the heat stress. Neuroimmune effects were assessed using an integrative approach of the observed immune, Central Nervous System (CNS) and/or hypothalamic-pituitary-adrenal (HPA) axis changes. Quantitative and semi-quantitative techniques were utilized to measure and compare the different degrees of tissue damage resulting from the infectious processes in the presence and absence of heat stress. Microbiological techniques were also used to determine C. perfringens and Eimeria spp. proliferations. Results showed that heat stress: reduced intestinal inflammation and tissue damage in the NE model that used C. perfringens together with thioglycolate broth culture medium intake; reduced the formation of splenic and intestinal germinal centers with subsequent production of serum and secretory immunoglobulins; activated some brain areas related to animals behavior and HPA axis activity; modified the brain-gut axis relationship during NE development; reduced Eimeria spp. infection leading to a subsequent reduction in the NE development and in the scores of tissue injury; together with NE, modified neuronal brain-amine systems activity and, as a consequence, changed animals behavior, HPA axis activity and brain amine systems fuction within some brain areas; predisposed the birds to C. perfringens infection in the presence or absence of NE inducing factors; reduced the tissue damages observed in the course of C. perfringens and Eimeria spp.co-infection; modulated cytokines to a Th2 pattern in animals infected or not; altered the splenic and peripheral blood lymphocytes subpopulations and, changed the proliferative function of immune cells and cytokine expression.Thus, we conclude that the heat stress and/or intestinal inflammation of infectious or chemical origin activate the HPA axis by a mechanism involving the brain-gut axis, reducing the clinical signs of NE by interfering in the pathogenesis of C. perfringens and Eimeria spp

Made available in DSpace on 2016-12-08T16:24:15Z (GMT). No. of bitstreams: 1 PGCA13MA115.pdf: 2445554 bytes, checksum: 3ef0e43758000b9d20b09e8f978e7502 (MD5) Previous issue date: 2013-07-10 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The species of the genus Eimeria are responsible for the greatest economic impact among the parasitic diseases that affect broilers. The control of coccidiosis is mainly performed with anticoccidial, however, the development of resistance to these drugs, together with the public opinion against the use of drugs in food, they tend to promote the use of vaccines, increasing the importance of the identification of species of Eimeria circulating. Aiming to identify the species of Eimeria and study the occurrence of these species in poultry farms in the southern state of Santa Catarina, samples were collected (pool of feces) in 21 municipalities, from 251 flocks of broilers aged 28 to 48 days. The oocysts were recovered by techniques of filtration, centrifugation and flotation using supersaturated solution of NaCl and quantified using a Neubauer chamber. The samples were stratified by age of the birds in three intervals (28 to 34, 35 to 41 and 42 to 48). The species were identified by Multiplex PCR technique. Amplicons of the seven species of Eimeria originating from the PCR positive samples have been cloned and sequenced. The occurrence of the genus Eimeria was 96.02%. It was found that in chickens aged 42 to 48 days the average number of oocytes was significantly reduced when compared to the intervals age of 28 to 34, and 35 to 41 days (p<0.05). Were found Eimeria acervulina (63.3%), Eimeria maxima (63,7%), Eimeria tenella (54.6%), Eimeria praecox (25.1%), Eimeria mitis (38.6%), Eimeria necatrix (24.3%) and Eimeria brunetti (13.1%). The average number of species detected by property was 2.96 and was the most frequent combination of E. acervulina, E. maxima and E. tenella (9.16%). The sequencing of the clones confirmed the specificity and effectiveness of the Multiplex PCR technique for identification of species of Eimeria. It can be concluded that in the South of the State, prophylactic measures should consider the control of the seven Eimeria species that parasitize chickens / As espécies do gênero Eimeria são responsáveis pelo maior impacto econômico dentre as doenças parasitárias que acometem frangos de corte. O controle da coccidiose é realizado principalmente com anticoccidianos, porém, o desenvolvimento da resistência a esses fármacos, aliada à opinião pública contra o uso de drogas na ração, tendem a fomentar a utilização de vacinas, aumentando a importância da identificação das espécies de Eimeria circulantes. Com os objetivos de identificar as espécies de Eimeria e estudar a ocorrência destas em instalações avícolas da mesorregião Sul do estado de Santa Catarina, foram coletadas amostras (pool de fezes) em 21 municípios, provenientes de 251 lotes de frangos de corte com idade entre 28 a 48 dias. Os oocistos foram recuperados por meio de técnicas de filtragem, centrifugação e centrífugo-flutuação utilizando solução hipersaturada de NaCl e quantificados utilizando câmara de Neubauer. As amostras foram estratificadas, por idade das aves em três intervalos (28 a 34; 35 a 41 e 42 a 48). As espécies foram identificadas por meio da técnica de Multiplex PCR. Amplicons das sete espécies de Eimeria originados da PCR de amostras positivas foram clonados e sequenciados. A ocorrência do gênero Eimeria foi de 96,02%. Verificou-se que em frangos com idade entre 42 a 48 dias a média do número de oocistos foi significativamente menor quando comparada com os intervalos de idade de 28 a 34 e 35 a 41 dias (P<0,05). Foram encontradas Eimeria acervulina (63,3%), Eimeria maxima (63,7%), Eimeria tenella (54,6%), Eimeria praecox (25,1%), Eimeria mitis (38,6%), Eimeria necatrix (24,3%) e Eimeria brunetti (13,1%). O número médio de espécies detectadas por propriedade foi de 2,96 e a associação mais frequente foi de E. acervulina, E. maxima e E. tenella (9,16%). Por meio do sequenciamento dos clones confirmou-se a especificidade e eficácia da técnica de Multiplex PCR para a identificação das espécies de Eimeria. Concluí-se que na mesorregião Sul do Estado, a adoção de medidas profiláticas deve considerar o controle das sete espécies de Eimeria que parasitam frangos

A coccidiose aviária é uma doença entérica causada por protozoários parasitas do gênero Eimeria. Visando uma maior compreensão dos mecanismos moleculares envolvidos na regulação do ciclo de vida dos parasitas, foram geradas 15.000 seqüências expressas (ORESTES) para cada uma das três espécies mais importantes: E. tenella, E. maxima e E. acervulina. O presente trabalho consistiu no desenvolvimento de componentes de anotação automática de seqüências para o sistema EGene, plataforma previamente desenvolvida pelo nosso grupo (Durham et al. Bioinformatics 21: 2812-2813, 2005) para a construção de processamentos encadeados (pipelines). Estes componentes foram utilizados para a construção de pipelines de anotação automática de seqüências-consenso obtidas a partir da montagem dos ORESTES de Eimeria spp. A anotação consistiu na identificação dos genes e atribuição da função dos respectivos produtos protéicos, baseando-se em um conjunto de evidências. As seqüências também foram classificadas e quantificadas utilizando-se um vocabulário controlado de termos de ontologia gênica (GO). / Avian coccidiosis is an enteric disease caused by protozoan parasites of the genus Eimeria. Aiming at obtaining a better understanding of the molecular mechanisms that regulate the life cycle of the parasites, our group generated 15,000 expressed sequences (ORESTES) for each one of the three most important species: E. tenella, E. maxima and E. acervulina. In the present work, we report the development of a set of components for the automated sequence annotation through EGene, a platform for pipeline construction previously described by our group (Durham et al. Bioinformatics 21: 2812-2813, 2005). These components were used to construct pipelines for the automated annotation of assembled sequences of ORESTES of Eimeria spp. The annotation process consisted in the identification of genes and the corresponding protein function based on a set of evidences. The sequences were also mapped and quantified using a controlled vocabulary of gene ontology (GO) terms.

In den vorliegenden Studien wurden verschiedene diagnostische Verfahren zum Nachweis von Protozoen und Nematoden im Hinblick auf Sensitivität, Arbeitsaufwand und Kosten miteinander verglichen. Zudem wurde die Eignung der PCR zur molekularen Charakterisierung der Cryptosporidium spp. exemplarisch an Igelkotproben getestet. Bei der Untersuchung von 90 Ferkelkotproben auf I. suis war die Sensitivität eines Kotausstriches mit nachfolgender Autofluoreszenzmikroskopie (AM) signifikant höher als bei einem Flotationsverfahren (FV) mit NaCl-Zucker-Lösung und bei dem kombinierten Sedimentations-Flotations-Verfahren (KSFV) mit verschiedenen Flotationslösungen (NaCl, ZnSO4, NaCl-Zucker-Lösung) mit nachfolgender Lichtmikroskopie. Zudem ist der Arbeitsaufwand für die AM deutlich geringer als bei dem FV und KSFV. Die höheren apparativen Kosten für die AM sind bei hohem Probendurchsatz durch den geringeren Zeitaufwand und der höheren Sensitivität gerechtfertigt. Die Anzahl Kryptosporidien-positiver Proben war bei der Untersuchung von 103 Kälberkotproben auf Cryptosporidium sp. mittels Enzymimmunoassays (EIA; ProSpecT® Cryptosporidium Microplate Assay) im Vergleich zur Karbolfuchsin-Färbung (CF) nach HEINE (1981) und der modifizierten-Ziehl-Neelsen-Färbung (MZN) nach HENRIKSEN u. POHLENZ (1982) am höchsten und signifikant höher als bei der Anwendung der MZN, wenn 10 Blickfelder durchmustert wurden. Bei der Untersuchung von 74 Igelkotproben auf Cryptosporidium sp. mittels EIA (ProSpecT®), einem immunochromatographischen Verfahren (FASTest® CRYPTO Strip), der MZN nach HENRIKSEN u. POHLENZ (1981) und einem direkten Immunfluoreszenz-Test (IFA; MERIFLUOR Cryptosporidium/Giardia) wurden in 9 (EIA), 10 (FASTest®), 11 (MZN) und 12 (IFA) Proben Cryptosporidium sp. nachgewiesen. Der Arbeitsaufwand des FASTest® und der CF ist mit dem EIA vergleichbar, während der IFA und die MZN mehr Zeit benötigen. Die Anwendung des FASTest®, des IFA und des EIA ist mit höheren Kosten verbunden als bei den Färbemethoden, können aber gut in den Arbeitsablauf eines diagnostischen Labors eingefügt werden und sind einfach auszuwerten. Darüber hinaus wurden 45 Kotproben, welche bis zu 27 Tage bei verschiedenen Temperaturen (+6 °C, +16 °C, +30 °C, +40 °C) gelagert wurden, untersucht, um einen Einfluss der Temperatur auf das Untersuchungsergebnis von EIA, CF und MZN zu ermitteln. Während sich die Anzahl positiver Proben bei der Untersuchung mit den Färbemethoden temperatur- und zeitabhängig reduzierte, wurde das Untersuchungsergebnis mittels EIA von der Lagerungstemperatur nicht beeinflusst, so dass ungekühlt transportierte Proben vorzugsweise mit dem EIA untersucht werden sollten. Dagegen ist die CF aufgrund ihrer einfachen und preiswerten Durchführung zur Untersuchung einer hohen Anzahl an Proben geeignet, sofern eine ununterbrochene Kühlung der Proben gewährleistet ist und diese innerhalb von drei Tagen untersucht werden. Der FASTest® ist zur Anwendung in Tierarztpraxen und Ställen geeignet, da zur Untersuchung kein Mikroskop benötigt wird und die Resultate schnell vorliegen. Die Verwendung des IFA, der Kryptosporidien-Oozysten und Giardien-Zysten nachweist, bietet sich vor allem bei Proben an, die auf beide Protozoen untersucht werden sollen. Das Vorkommen der Kryptosporidiose bei unterentwickelten und geschwächten Igeln, welche zum Überwintern in Igelstationen aufgenommen werden, ist hoch. Von 188 untersuchten Igelkotproben konnten in 29,8 % der Proben Cryptosporidium spp. nachgewiesen werden. Durch die Genotypisierung der Kryptosporidien aus 15 positiven Igelkotproben mittels RFLP-PCR basierend auf dem 18S rRNA-Gen konnte in allen untersuchten Proben die Präsenz von C. parvum gezeigt werden. Mit Hilfe der Multilocus-Sequenz-Typisierung der Fragmente des 60kDa Glycoprotein-Gens, des 18S rRNA-Gens, des Actin-Gens und des 70 kDa Hitzeschockprotein-Gens konnten drei verschiedene Subtypen-Familien (IIa, IIc und eine neue als VIIa vorgeschlagene Subtypen-Familie) erkannt werden. Die von den Igeln ausgeschiedenen Kryptosporidien-Oozysten mit zum Teil nachgewiesenem zoonotischen Potential (IIa Subtypen-Familie) könnten eine Infektionsquelle für den Menschen sein, aber auch ein antropozoonotisches Potential (IIc Subtypen-Familie) sollte in Betracht gezogen werden, so dass die Hygiene in den Igelstationen einen hohen Stellenwert einnehmen sollte. Die Untersuchungsergebnisse zum Nachweis von Eimeria-Arten beim Kalb von 70 Sammelkotproben, hergestellt aus 10 Einzelkotproben (SKP10), bzw. von 30 Sammelkotproben, zusammengesetzt aus 5 Einzelkotproben (SKP5), wurden mit denen der zugehörigen Einzelkotproben (EKP) verglichen. Die Resultate der EKP (arithmetischer Mittelwert) und der zugehörigen SKP weisen mit den signifikant häufigeren Abweichungen im Bereich von bis zu 100 Oozysten pro Gramm Kot (OpG) eine geringe Differenz zwischen den beiden Verfahren auf. Durch den sicheren Nachweis von Eimeria-Oozysten bei einem erwarteten Oozystengehalt von nur 202 OpG (SKP10) und 122 OpG (SKP5) ist die Untersuchung von Kälbersammelkotproben, eine Methode mit geringem Arbeitsaufwand und geringen Untersuchungskosten, zum Nachweis einer klinischen oder subklinischen Kokzidiose geeignet. Bei 51 Pferdekotproben wurde jeweils dreimal das kombinierte Sedimentations-Flotations-Verfahren (KSFV), wobei die Entnahme von verschiedenen Lokalisationen der Kotprobe (aus der Randregion, dem Inneren oder aus beiden Lokalisationen) erfolgte, und jeweils dreimal das KSFV mit vorheriger Homogenisierung einer größeren Kotmenge zum Nachweis von Nematodeneier durchgeführt. Eine Anhäufung der Strongyliden- und Ascarideneier in einem bestimmten Bereich der Proben konnte durch die Untersuchungen der verschiedenen Lokalisationen (á 10 g Kot) nicht nachgewiesen werden, so dass eine weitgehend homogene Verteilung dieser Nematodeneier in einer Pferdekotprobe wahrscheinlich ist. Zudem konnten die Untersuchungsergebnisse des KSFV, bei welchem 10 g Kot untersucht werden, durch die vorherige Homogenisierung einer größeren Probenmenge nicht verbessert werden. Zum Nachweis von Nematoden beim Pferd sollte dem Labor eine ausreichende Probenmenge (ca. 50 g) zugesandt werden. Die Homogenisierung einer größeren Probenmenge vor der Durchführung einer diagnostischen Methode, bei der Aliquote von mindestens 10 g Kot Verwendung finden, ist unnötig. / The studies presented were carried out to compare different diagnostic methods for detection of protozoa and nematodes regarding sensitivity, expenditure of human labour and costs. Besides, the ability of the PCR for the molecular characterization of the Cryptosporidium spp. was tested exemplarily in faecal samples of hegdehogs. The examination of ninety faecal samples of suckling piglets showed a significantly higher sensitivity of faecal smears examined by autofluorescence microscopy (AM) compared to the flotation method (FV) using NaCl-sucrose solution and the combined sedimentation-flotation method (KSFV) using different flotation solutions (NaCl, ZnSO4, NaCl-sucrose) scanned by bright field microscopy. Moreover the expenditure of human labour by AM is considerably lower than FV and KSFV. The costs related to equipment for AM is justified in case of high sample throughput and by superior sensitivity. The enzyme immunoassay (EIA; ProSpecT® Cryptosporidium Microplate Assay) was the most sensitive method for diagnosis of cryptosporidiosis in calves (n = 103) compared to the carbol fuchsin (CF; HEINE 1981) and modified Ziehl-Neelsen (MZN; HENRIKSEN a. POHLENZ 1982) staining techniques. The sensitivity of the EIA was significantly higher than the MZN, if ten fields of view were scanned. 74 faecal samples of hedgehogs were examined with the EIA (ProSpecT®), an immunochromatographic method (FASTest® CRYPTO Strip), the MZN (HENRIKSEN u. POHLENZ (1981)) and a direct immunofluorescent assay (IFA; MERIFLUOR Cryptosporidium/Giardia). Cryptosporidium sp. were detected in 9 (EIA), 10 (FASTest®), 11 (MZN) und 12 (IFA) faecal samples. The hands on time of the FASTest® and CF is comparable to EIA while the IFA and MZN are more time-consuming. The examination of the FASTest®, IFA and EIA is combined with higher costs than the staining techniques, but they can be integrated in the work flow of a routine diagnostic laboratory easily and evaluation is simple. Moreover 45 faecal samples stored up to 27 days at different temperature (+6 °C, +16 °C, +30 °C, +40 °C) were examined to evaluate the influence of temperature on the results of EIA, CF and MZN. While the number of the positive samples of stained smears decreased in a temperature and time-dependent manner, the results of the EIA were not influenced by sample storage at any temperature, so that samples transported without cooling should be examined preferably by EIA. Nevertheless the CF due to its simplicity and low costs is suited for scanning of a high number of samples, if they were cooled continuously and examined within three days. The FASTest® is qualified for use in veterinary practice and stables, because the examination requires no microscope and the results are obtained immediately. The IFA, which can detect Crypotsporidium oocysts as well as Giardia cysts, is suited especially for faecal samples suspected to contain both protozoa. Cryptosporidial infections are very frequent in hedgehogs which are admitted for hibernation to hedgehog rehabilitation centres because of their insufficient body weight and weakness. Cryptosporidium spp. were detected in 29.8 % of 188 faecal samples of hedgehogs. The genotyping of Cryptosporidium spp. by PCR and RFLP-PCR based on the 18S ribosomal RNA gene were performed on 15 faecal samples of hedgehogs positive for Cryptosporidium spp. and suggested the presence of C. parvum in all samples. Multilocus sequence typing on partial 60 kDa glycoprotein gene, 18S rRNA gene, actine gene, 70 kDa heat shock protein gene sequences revealed 3 different subtype families: IIa, IIc and a new proposed as VIIa subtype family. Some of the Cryptosporidium oocysts excreted from hedgehogs are zoonotical (IIa subtype family) or anthropozoonotic(IIc subtype family). Thus hygienic measurements to avoid transmission are essential in hedgehog rehabilitation centres. The results of examination of 70 pooled faecal samples originating from 10 calves (SKP10) and 30 pooled faecal samples originating from 5 calves (SKP5) for detection of Eimeria spp. were compared with the arithmetic means of opg (oocysts per gram of faeces) counts of the respective single 10 or 5 samples. A low difference between both methods of less than 100 opg was significantly more frequently observed than higher differences. Low values of 202 opg and 122 opg were reliably detected in SKP10 und SKP5, respectively, and thus examination of pooled faecal samples appears to be suitably sensitive and cost effective to detect clinical and subclinical coccidiosis in calves. 51 faecal samples of horses were examined three times by KSFV for nematode eggs by taking aliquots from different locations of the same faecal samples (from the margin, from inside and from both locations). Thereafter the KSFV with the homogenisation of a larger amount of faeces was also carried out three times. The examination of samples from the different locations (each 10 g of faeces) delivered no evidence for accumulation of nematode eggs (strongyles and Parascaris equorum) in the faeces and thus the distribution of the nematode eggs appears sufficiently homogeneous in faecal samples of horses. Homogenisation of a larger amount of faeces did not improve the results of coproscopy. For diagnostic purposes 50 g faeces per sample should be shipped to the laboratory. The homogenisation of a larger amount of faeces before using a diagnostic method is dispensable, if aliquots of 10 g faeces are examined.

In der vorliegenden Arbeit wurden die Ergebnisse von 263 Einzeltierverfolgungen in 12 Betrieben in verschiedenen Regionen in Deutschland, Belgien, Frankreich und der Tschechischen Republik zur Stallkokzidiose der Kälber zusammengefasst ausgewertet. Während diesen Untersuchungen wurden 5840 Kotproben beurteilt. Dabei wurden das Auftreten und die Ausprägung der Eimeriose der Kälber analysiert und potentielle Einflussfaktoren untersucht und ein verlässlicher Schwellenwert für die Bewertung der Oozystenausscheidung ermittelt. Weiterhin wurden in 16 Betrieben bei 23 gemeinsam aufgestallten Kälbergruppen Spezies-Prävalenzuntersuchungen über einen Zeitraum von fünf Wochen durchgeführt. Hierfür wurden 5133 Proben ausgewertet, davon 3519 mit Teil- und 1614 mit vollständiger Differenzierung. In allen Betrieben traten die Kotkzidiosen als eine Mischinfektion verschiedener Eimeria-Arten auf. Dabei herrschte in der Regel in jedem Betrieb eine der beiden pathogensten Spezies vor. Diese Prädominanz blieb auch über mehrere Jahre gleich in den Betrieben. Die Herkunft der Kälber hatte einen Einfluss auf den Infektionsverlauf. In Betrieben mit ausschließlich eigener Nachzucht verläuft die Kokzidiose als eingipflige Infektion, bei Zukaufbetrieben ist der Infektionsverlauf zweigipflig. Ein signifikant erhöhtes Risiko des Auftretens einer klinisch ausgeprägten Kokzidiose bei Aufstallung auf Stroheinstreu im Vergleich zur Haltung auf Spaltenboden konnte bewiesen werden (p = 0,005). In der Verfolgungsuntersuchung korrelierten die Kokonsistenzwerte mit den nachgewiesenen OpG in den Kotproben positiv signifikant (0,135 Korrelationskoeffizient; p = 0,000). Für das Auftreten von Durchfall konnte eine statistisch bewiesene lineare Korrelation mit der Oozystenausscheidung für diverse Schwellenwerte festgestellt werden (p = 0,000). Bei einem Grenzwert von 500 OpG lag der Korrelationskoeffizient bei 0,149. Die Korrelationswerte erhöhten sich nicht wesentlich bei Festlegung eines höheren Grenzwertes für die Oozystenausscheidung oder sanken sogar (0,153 bis 0,121). Bei der Verrechnung von Durchfallvorkommen mit gleichzeitiger, potentiell relevanter Oozystenausscheidung mit den verschiedenen Schwellenwerten der Oozystenausscheidung konnte der höchste Zusammenhang zwischen dem Durchfallgeschehen und dem Schwellenwert von 500 OpG bewiesen werden (0,633 Korrelationskoeffizient; p = 0,000). Daher kann ein Wert von 500 OpG pathogener Eimeria spp. als geeigneter Schwellenwert für die Feststellung einer relevanten Oozystenausscheidung angesehen werden. Bei gleichzeitigem Auftreten von Durchfall ist von einer maßgeblichen Beteiligung der Eimerien auszugehen. Ein gehäuftes Auftreten von mit Oozystenausscheidung assoziierten Durchfällen trat bei Tieren ohne oder ohne potentiell relevante Oozystenausscheidung (‚rK -’) signifikant seltener auf (p = 0,000) als bei Tieren mit mindestens 500 aufsummierten OpG während des gesamten Beobachtungszeitraumes (‚rK +’). Kälber der Kategorie ‚Kok-Kat 1’ hatten signifikant niedrigere Kotkonsistenzwerte und weniger Durchfälle als Tiere der Subpopulation ‚rK -’ (p = 0,000). Dagegen hatten die Tiere der Auswertungsgruppe ‚Kok-Kat 2’ statistisch bewiesen in allen Durchfall-Kategorien höhere Werte bzw. ein häufigeres Durchfallvorkommen als beide anderen Subpopulationen (p = 0,000 für alle Vergleiche). Wässrige Durchfälle mit Beimengungen traten, mit Ausnahme einer Einzelbeobachtung in Gruppe ‚rK -’, ausschließlich bei Kälbern der Auswertungsgruppe ‚Kok-Kat 2’ auf. Sowohl Kälber der Gruppe ‚rK +’ als auch ‚Kok-Kat 2’-Tiere (jeweils p = 0,000) und Kälber mit potentiell relevanter Oozystenausscheidung, aber ohne gleichzeitiges Durchfallgeschehen, (‚Kok-Kat 1’) (p = 0,005) hatten signifikant geringere relative Gewichtszunahmen als Tiere ohne bzw. ohne potentiell relevante Oozystenausscheidung (‚rK -’). Eine lineare Korrelation der Ausscheidung der pathogenen Spezies E. bovis und E. zuernii mit den absoluten (-0,098 Korrelationskoeffizient; p = 0,005) und relativen Gewichtszunahmen (-0,170 Korrelationskoeffizient; p = 0,000) konnte statistisch bewiesen werden. Bei Haltung auf Stroheinstreu zeigten Tiere ohne bzw. mit weniger als 500 ausgeschiedenen OpG im Untersuchungszeitraum (‚rK -’) signifikant höhere relative Zunahmen im Vergleich zu Tieren mit potentiell relevanter Oozystenausscheidung (p = 0,000). Dabei war es ohne Bedeutung, ob diese Kälber ein gleichzeitiges Durchfallgeschehen zeigten oder nicht. Besonders zum Tragen kommen diese Unterschiede in der Gewichtsentwicklung in den Wochen mit den höchsten Oozystenausscheidungen bei zweigipfligem Infektionsverlauf. Unter den Milchviehkälbern nahmen Tiere ohne relevante Oozystenausscheidung signifikant mehr relatives Gewicht zu als Kälber mit kumulativ mindestens 500 OpG im Untersuchungszeitraum (p = 0,004). Dies galt sowohl für Tiere mit gleichzeitigem Durchfall ‚Kok-Kat 2’ (p = 0,002) als auch tendenziell für Kälber der Gruppe ‚Kok-Kat 1’ (p = 0,059). Mastviehkälber der Gruppe ‚rK -’ zeigten signifikant höhere relative Zunahmen im Vergleich zu Tieren mit potentiell relevanter Oozystenausscheidung ‚rK +’ (p = 0,039). Dies galt auch in Relation zu den Kälbern der Auswertungsgruppe ‚Kok-Kat 1’ (p = 0,029). Während der Prävalenzuntersuchungen wurden insgesamt neun verschiedene Eimeria-Arten nachgewiesen. In Einzelkotproben wurden zwischen einer und neun verschiedene Spezies beobachtet. Unter den in Europa als heimisch bekannten Arten wurden während dieser Untersuchung lediglich E. wyomingensis, E. brasiliensis und E. bukidnonensis nicht gefunden. E. ellipsoidalis hatte sowohl die höchste Inzidenz (20,99 %) als auch die größte Intensität (arithmetischer Mittelwert von 765963,37 OpG), gefolgt von E. bovis und E. zuernii. Zudem wurde in Aufzuchtbetrieben E. ellipsoidalis in der Regel als erste Eimeria-Spezies, gefolgt von E. auburnensis und den pathogenen Arten E. zuernii und E. bovis, nachgewiesen. Die seltensten Spezies waren E. canadensis und E. pellita. Eimeria pellita wurde als letzte Art erst ab der fünften Woche nach Aufstallung beobachtet. E. cylindrica trat vermehrt in den Betrieben in Belgien und Frankreich auf. Diese Art sowie E. canadensis wurden nur in Betrieben in Bayern, Belgien und Frankreich festgestellt. E. pellita hatte, neben E. canadensis, die geringsten Prävalenzen, Nachweise wurden vor allem für zentral gelegene Betriebe sowie im Süden des Untersuchungsgebietes dokumentiert. Die Übereinstimmung der gefundenen Varianzen der Speziesprävalenzen der vorliegenden Untersuchung mit den Daten epidemiologischer Studien in den verschiedenen Regionen aus der Literatur bestätigt einen repräsentativen Charakter der Untersuchungsbetriebe. Dies belegt zusätzlich die Allgemeingültigkeit der festgestellten Einflussfaktoren auf das Auftreten und die Auswirkungen der Stallkokzidiose der Kälber. / A total number of 263 calves housed on 12 different farms in several regions in Germany, Belgium, France and the Czech Republic were followed individually in tracking studies and data was compiled and analysed to investigate factors influencing occurrence and severity of bovine eimeriosis of housed calves. The same data was used for development and verification of a suitable threshold indicating relevant oocyst excretion. Within the tracking studies a total number of 5840 faecal samples were examined for faecal consistency, oocyst counts of pathogenic E. bovis and E. zuernii excretion carried out and individual body weight development was documented regularly. Additionally 23 groups of animals on 16 farms were observed for a period of five weeks and 5133 faecal samples examined for oocyst excretion and Eimeria species differentiated. All study sites were positive for mixed coccidia species infections. Nevertheless all farms except one showed a predominance of one pathogenic Eimeria species, which remained unchanged in different groups of animals and even in different years of investigations. Animal origin, i.e. groups of animals representing own breeding or originating of only one source in contrast to groups of calves coming from several origins, influences the course of the coccidiosis infection. Farms with only one single and permanent animal origin or raising exclusively the own breeding show coccidiosis with a single peak of oocyst excretion. On farms housing groups of animals of various origins the course of infection and oocyst shedding has typically two peaks with an interval of two to three weeks. The risk for development of clinical coccidiosis rises significantly if animals were housed on straw bedding compared to slatted-floor (p = 0.005). Faecal scores correlated significantly (p = 0.000) with the intensity of oocyst excretion with a positive correlation coefficient of 0.135. For occurrence of diarrhoea a positive linear correlation with the oocyst excretion was statistically proved (p = 0.000) for various thresholds. At a threshold of 500 opg of E. bovis and E. zuernii the correlation coefficient rised to 0.149 and correlation coefficients did not rise distinctly or even got down if higher thresholds were used (values between 0.153 and 0.121). Focusing only on potentially coccidiosis related diarrhoea the threshold of 500 opg of E. bovis and E. zuernii proved to result in the highest correlation (0.633; p = 0.000) of all tested threshold levels. Therefore the threshold of 500 opg of E. bovis and E. zuernii can be accounted modest and reliable to detect a relevant oocyst excretion in individual faecal samples as well as in compiled samples. In cases of coincidental diarrhoea coccidiosis can be considered as a major factor. Increased numbers of days with diarrhoea in coincidence with an oocyst excretion (‘Kokass-DF’) within the observation period were seen significantly more often (p = 0.000) in animals with a potentially relevant oocyst excretion (‘rK +’) of at least 500 summed up opg of E. bovis and E. zuernii in comparison to calves without such an oocyst excretion (‘rK -‘). Significantly lower faecal scores and fewer days with diarrhoea were documented for calves of the group ‘Kok-Kat 1’ in contrast to animals of group ‘rK -‘ (p = 0.000). Nevertheless significantly higher faecal scores and more days with diarrhoea than both other groups were calculated for those calves meeting the inclusion criteria for group ‘Kok-Kat 2’ (p = 0.000 for all comparisons). Additionally liquid faeces or faeces with constituencies were seen only in this group, except for one single sample of a calf of group ‘rK -‘. Calves of evaluation group ‘rK +’ as well as both subpopulations representing group ‘Kok-Kat 2’ and calves with potentially relevant oocyst excretion but without diarrhoea associated to an oocyst excretion (‘Kok-Kat 1’) showed significant lower values for relative body weight increases in comparison to animals without relevant oocyst excretion throughout the complete study period of five weeks (‘rK -‘) (p = 0.000 vs. ‘rK +’ and vs. ‘Kok-Kat 2‘; p = 0.005 compared with ‘Kok-Kat 1’). A negative linear correlation between oocyst excretion of pathogenic Eimeria spp. and absolute (-0.098 correlation coefficient; p = 0.005) as well as relative body weight gain (-0.170 correlation coefficient) was verified statistically (p = 0.000). Animals housed on straw bedding and belonging to the group ‘rK -‘ gained relatively more body weight in comparison to calves housed in the same stables and meeting the inclusion criterium of group ‘rK +’, i.e. excreting at least 500 summed up opg of pathogenic E. spp., (p = 0.000) within the total study period. The presence of coincidental diarrhoea had no impact on impaired body weight development of animals with a potentially relevant coccidia excretion. Differences in body weight development were most distinct within the weeks of highest intensities in oocyst excretion according to a course of infection with two peaks. Within the subpopulation of dairy calves those animals belonging to evaluation group ‘rK -‘ developed significantly higher relative body weight gains compared to group ‘rK +’ (p = 0.004). Similar results were found for animals of group ‘Kok-Kat 2’ (p = 0.002) and a statistical tendency was calculated for group ‘Kok-Kat 1’ (p = 0.059) in comparison to group ‘rK -‘. Analogous to the differences in dairy calves animals on fattening farms without relevant oocyst excretion (‘rK -’) had significantly higher relative body weight gains compared to calves of evaluation group ‘rK +’ (p = 0.039) and animals of group ‘Kok-Kat 1’ (p = 0.029) of the same breeds and farms. Nine different Eimeria spp. were detected during the prevalence studies. In single individual samples a minimum of one and up to nine different species were found. Twelve Eimeria spp. are known to be endemic in Europe of which only E. brasiliensis, E. bukidnonensis and E. wyomingensis were not present in any faecal sample in this study. E. bovis and E. zuernii were only second to E. ellipsoidalis which had the highest prevalence (20.99 %) as well as the highest intensity (765963.37 mean opg) in the faecal samples examined. In breeding farms E. ellipsoidalis was the first species to be found in faecal examination in most cases, followed by E. auburnensis and the pathogenic species E. zuernii and E. bovis. E. canadensis and E. pellita were detected only in a low number of samples. E. pellita was observed for the first time at the faecal samplings five weeks after stabling and mainly in farms situated in the central and southern region of the prevalence study. E. canadensis and E. cylindrica were most prominent in farms situated in Belgium and France. Variances in prevalence of the species observed are in conformity with those to be found in recent literature according to the different regions of Europe. This may indicate a representative character of the farms participating in this study and therefore universal validity of the results and impactfactors on coccidiosis in calves described in this manuscript.

A coccidiose aviária é uma doença entérica causada por protozoários parasitas do gênero Eimeria. Visando uma maior compreensão dos mecanismos moleculares envolvidos na regulação do ciclo de vida dos parasitas, foram geradas 15.000 seqüências expressas (ORESTES) para cada uma das três espécies mais importantes: E. tenella, E. maxima e E. acervulina. O presente trabalho consistiu no desenvolvimento de componentes de anotação automática de seqüências para o sistema EGene, plataforma previamente desenvolvida pelo nosso grupo (Durham et al. Bioinformatics 21: 2812-2813, 2005) para a construção de processamentos encadeados (pipelines). Estes componentes foram utilizados para a construção de pipelines de anotação automática de seqüências-consenso obtidas a partir da montagem dos ORESTES de Eimeria spp. A anotação consistiu na identificação dos genes e atribuição da função dos respectivos produtos protéicos, baseando-se em um conjunto de evidências. As seqüências também foram classificadas e quantificadas utilizando-se um vocabulário controlado de termos de ontologia gênica (GO). / Avian coccidiosis is an enteric disease caused by protozoan parasites of the genus Eimeria. Aiming at obtaining a better understanding of the molecular mechanisms that regulate the life cycle of the parasites, our group generated 15,000 expressed sequences (ORESTES) for each one of the three most important species: E. tenella, E. maxima and E. acervulina. In the present work, we report the development of a set of components for the automated sequence annotation through EGene, a platform for pipeline construction previously described by our group (Durham et al. Bioinformatics 21: 2812-2813, 2005). These components were used to construct pipelines for the automated annotation of assembled sequences of ORESTES of Eimeria spp. The annotation process consisted in the identification of genes and the corresponding protein function based on a set of evidences. The sequences were also mapped and quantified using a controlled vocabulary of gene ontology (GO) terms.

In der vorliegenden Arbeit wurden die Ergebnisse von 263 Einzeltierverfolgungen in 12 Betrieben in verschiedenen Regionen in Deutschland, Belgien, Frankreich und der Tschechischen Republik zur Stallkokzidiose der Kälber zusammengefasst ausgewertet. Während diesen Untersuchungen wurden 5840 Kotproben beurteilt. Dabei wurden das Auftreten und die Ausprägung der Eimeriose der Kälber analysiert und potentielle Einflussfaktoren untersucht und ein verlässlicher Schwellenwert für die Bewertung der Oozystenausscheidung ermittelt. Weiterhin wurden in 16 Betrieben bei 23 gemeinsam aufgestallten Kälbergruppen Spezies-Prävalenzuntersuchungen über einen Zeitraum von fünf Wochen durchgeführt. Hierfür wurden 5133 Proben ausgewertet, davon 3519 mit Teil- und 1614 mit vollständiger Differenzierung. In allen Betrieben traten die Kotkzidiosen als eine Mischinfektion verschiedener Eimeria-Arten auf. Dabei herrschte in der Regel in jedem Betrieb eine der beiden pathogensten Spezies vor. Diese Prädominanz blieb auch über mehrere Jahre gleich in den Betrieben. Die Herkunft der Kälber hatte einen Einfluss auf den Infektionsverlauf. In Betrieben mit ausschließlich eigener Nachzucht verläuft die Kokzidiose als eingipflige Infektion, bei Zukaufbetrieben ist der Infektionsverlauf zweigipflig. Ein signifikant erhöhtes Risiko des Auftretens einer klinisch ausgeprägten Kokzidiose bei Aufstallung auf Stroheinstreu im Vergleich zur Haltung auf Spaltenboden konnte bewiesen werden (p = 0,005). In der Verfolgungsuntersuchung korrelierten die Kokonsistenzwerte mit den nachgewiesenen OpG in den Kotproben positiv signifikant (0,135 Korrelationskoeffizient; p = 0,000). Für das Auftreten von Durchfall konnte eine statistisch bewiesene lineare Korrelation mit der Oozystenausscheidung für diverse Schwellenwerte festgestellt werden (p = 0,000). Bei einem Grenzwert von 500 OpG lag der Korrelationskoeffizient bei 0,149. Die Korrelationswerte erhöhten sich nicht wesentlich bei Festlegung eines höheren Grenzwertes für die Oozystenausscheidung oder sanken sogar (0,153 bis 0,121). Bei der Verrechnung von Durchfallvorkommen mit gleichzeitiger, potentiell relevanter Oozystenausscheidung mit den verschiedenen Schwellenwerten der Oozystenausscheidung konnte der höchste Zusammenhang zwischen dem Durchfallgeschehen und dem Schwellenwert von 500 OpG bewiesen werden (0,633 Korrelationskoeffizient; p = 0,000). Daher kann ein Wert von 500 OpG pathogener Eimeria spp. als geeigneter Schwellenwert für die Feststellung einer relevanten Oozystenausscheidung angesehen werden. Bei gleichzeitigem Auftreten von Durchfall ist von einer maßgeblichen Beteiligung der Eimerien auszugehen. Ein gehäuftes Auftreten von mit Oozystenausscheidung assoziierten Durchfällen trat bei Tieren ohne oder ohne potentiell relevante Oozystenausscheidung (‚rK -’) signifikant seltener auf (p = 0,000) als bei Tieren mit mindestens 500 aufsummierten OpG während des gesamten Beobachtungszeitraumes (‚rK +’). Kälber der Kategorie ‚Kok-Kat 1’ hatten signifikant niedrigere Kotkonsistenzwerte und weniger Durchfälle als Tiere der Subpopulation ‚rK -’ (p = 0,000). Dagegen hatten die Tiere der Auswertungsgruppe ‚Kok-Kat 2’ statistisch bewiesen in allen Durchfall-Kategorien höhere Werte bzw. ein häufigeres Durchfallvorkommen als beide anderen Subpopulationen (p = 0,000 für alle Vergleiche). Wässrige Durchfälle mit Beimengungen traten, mit Ausnahme einer Einzelbeobachtung in Gruppe ‚rK -’, ausschließlich bei Kälbern der Auswertungsgruppe ‚Kok-Kat 2’ auf. Sowohl Kälber der Gruppe ‚rK +’ als auch ‚Kok-Kat 2’-Tiere (jeweils p = 0,000) und Kälber mit potentiell relevanter Oozystenausscheidung, aber ohne gleichzeitiges Durchfallgeschehen, (‚Kok-Kat 1’) (p = 0,005) hatten signifikant geringere relative Gewichtszunahmen als Tiere ohne bzw. ohne potentiell relevante Oozystenausscheidung (‚rK -’). Eine lineare Korrelation der Ausscheidung der pathogenen Spezies E. bovis und E. zuernii mit den absoluten (-0,098 Korrelationskoeffizient; p = 0,005) und relativen Gewichtszunahmen (-0,170 Korrelationskoeffizient; p = 0,000) konnte statistisch bewiesen werden. Bei Haltung auf Stroheinstreu zeigten Tiere ohne bzw. mit weniger als 500 ausgeschiedenen OpG im Untersuchungszeitraum (‚rK -’) signifikant höhere relative Zunahmen im Vergleich zu Tieren mit potentiell relevanter Oozystenausscheidung (p = 0,000). Dabei war es ohne Bedeutung, ob diese Kälber ein gleichzeitiges Durchfallgeschehen zeigten oder nicht. Besonders zum Tragen kommen diese Unterschiede in der Gewichtsentwicklung in den Wochen mit den höchsten Oozystenausscheidungen bei zweigipfligem Infektionsverlauf. Unter den Milchviehkälbern nahmen Tiere ohne relevante Oozystenausscheidung signifikant mehr relatives Gewicht zu als Kälber mit kumulativ mindestens 500 OpG im Untersuchungszeitraum (p = 0,004). Dies galt sowohl für Tiere mit gleichzeitigem Durchfall ‚Kok-Kat 2’ (p = 0,002) als auch tendenziell für Kälber der Gruppe ‚Kok-Kat 1’ (p = 0,059). Mastviehkälber der Gruppe ‚rK -’ zeigten signifikant höhere relative Zunahmen im Vergleich zu Tieren mit potentiell relevanter Oozystenausscheidung ‚rK +’ (p = 0,039). Dies galt auch in Relation zu den Kälbern der Auswertungsgruppe ‚Kok-Kat 1’ (p = 0,029). Während der Prävalenzuntersuchungen wurden insgesamt neun verschiedene Eimeria-Arten nachgewiesen. In Einzelkotproben wurden zwischen einer und neun verschiedene Spezies beobachtet. Unter den in Europa als heimisch bekannten Arten wurden während dieser Untersuchung lediglich E. wyomingensis, E. brasiliensis und E. bukidnonensis nicht gefunden. E. ellipsoidalis hatte sowohl die höchste Inzidenz (20,99 %) als auch die größte Intensität (arithmetischer Mittelwert von 765963,37 OpG), gefolgt von E. bovis und E. zuernii. Zudem wurde in Aufzuchtbetrieben E. ellipsoidalis in der Regel als erste Eimeria-Spezies, gefolgt von E. auburnensis und den pathogenen Arten E. zuernii und E. bovis, nachgewiesen. Die seltensten Spezies waren E. canadensis und E. pellita. Eimeria pellita wurde als letzte Art erst ab der fünften Woche nach Aufstallung beobachtet. E. cylindrica trat vermehrt in den Betrieben in Belgien und Frankreich auf. Diese Art sowie E. canadensis wurden nur in Betrieben in Bayern, Belgien und Frankreich festgestellt. E. pellita hatte, neben E. canadensis, die geringsten Prävalenzen, Nachweise wurden vor allem für zentral gelegene Betriebe sowie im Süden des Untersuchungsgebietes dokumentiert. Die Übereinstimmung der gefundenen Varianzen der Speziesprävalenzen der vorliegenden Untersuchung mit den Daten epidemiologischer Studien in den verschiedenen Regionen aus der Literatur bestätigt einen repräsentativen Charakter der Untersuchungsbetriebe. Dies belegt zusätzlich die Allgemeingültigkeit der festgestellten Einflussfaktoren auf das Auftreten und die Auswirkungen der Stallkokzidiose der Kälber. / A total number of 263 calves housed on 12 different farms in several regions in Germany, Belgium, France and the Czech Republic were followed individually in tracking studies and data was compiled and analysed to investigate factors influencing occurrence and severity of bovine eimeriosis of housed calves. The same data was used for development and verification of a suitable threshold indicating relevant oocyst excretion. Within the tracking studies a total number of 5840 faecal samples were examined for faecal consistency, oocyst counts of pathogenic E. bovis and E. zuernii excretion carried out and individual body weight development was documented regularly. Additionally 23 groups of animals on 16 farms were observed for a period of five weeks and 5133 faecal samples examined for oocyst excretion and Eimeria species differentiated. All study sites were positive for mixed coccidia species infections. Nevertheless all farms except one showed a predominance of one pathogenic Eimeria species, which remained unchanged in different groups of animals and even in different years of investigations. Animal origin, i.e. groups of animals representing own breeding or originating of only one source in contrast to groups of calves coming from several origins, influences the course of the coccidiosis infection. Farms with only one single and permanent animal origin or raising exclusively the own breeding show coccidiosis with a single peak of oocyst excretion. On farms housing groups of animals of various origins the course of infection and oocyst shedding has typically two peaks with an interval of two to three weeks. The risk for development of clinical coccidiosis rises significantly if animals were housed on straw bedding compared to slatted-floor (p = 0.005). Faecal scores correlated significantly (p = 0.000) with the intensity of oocyst excretion with a positive correlation coefficient of 0.135. For occurrence of diarrhoea a positive linear correlation with the oocyst excretion was statistically proved (p = 0.000) for various thresholds. At a threshold of 500 opg of E. bovis and E. zuernii the correlation coefficient rised to 0.149 and correlation coefficients did not rise distinctly or even got down if higher thresholds were used (values between 0.153 and 0.121). Focusing only on potentially coccidiosis related diarrhoea the threshold of 500 opg of E. bovis and E. zuernii proved to result in the highest correlation (0.633; p = 0.000) of all tested threshold levels. Therefore the threshold of 500 opg of E. bovis and E. zuernii can be accounted modest and reliable to detect a relevant oocyst excretion in individual faecal samples as well as in compiled samples. In cases of coincidental diarrhoea coccidiosis can be considered as a major factor. Increased numbers of days with diarrhoea in coincidence with an oocyst excretion (‘Kokass-DF’) within the observation period were seen significantly more often (p = 0.000) in animals with a potentially relevant oocyst excretion (‘rK +’) of at least 500 summed up opg of E. bovis and E. zuernii in comparison to calves without such an oocyst excretion (‘rK -‘). Significantly lower faecal scores and fewer days with diarrhoea were documented for calves of the group ‘Kok-Kat 1’ in contrast to animals of group ‘rK -‘ (p = 0.000). Nevertheless significantly higher faecal scores and more days with diarrhoea than both other groups were calculated for those calves meeting the inclusion criteria for group ‘Kok-Kat 2’ (p = 0.000 for all comparisons). Additionally liquid faeces or faeces with constituencies were seen only in this group, except for one single sample of a calf of group ‘rK -‘. Calves of evaluation group ‘rK +’ as well as both subpopulations representing group ‘Kok-Kat 2’ and calves with potentially relevant oocyst excretion but without diarrhoea associated to an oocyst excretion (‘Kok-Kat 1’) showed significant lower values for relative body weight increases in comparison to animals without relevant oocyst excretion throughout the complete study period of five weeks (‘rK -‘) (p = 0.000 vs. ‘rK +’ and vs. ‘Kok-Kat 2‘; p = 0.005 compared with ‘Kok-Kat 1’). A negative linear correlation between oocyst excretion of pathogenic Eimeria spp. and absolute (-0.098 correlation coefficient; p = 0.005) as well as relative body weight gain (-0.170 correlation coefficient) was verified statistically (p = 0.000). Animals housed on straw bedding and belonging to the group ‘rK -‘ gained relatively more body weight in comparison to calves housed in the same stables and meeting the inclusion criterium of group ‘rK +’, i.e. excreting at least 500 summed up opg of pathogenic E. spp., (p = 0.000) within the total study period. The presence of coincidental diarrhoea had no impact on impaired body weight development of animals with a potentially relevant coccidia excretion. Differences in body weight development were most distinct within the weeks of highest intensities in oocyst excretion according to a course of infection with two peaks. Within the subpopulation of dairy calves those animals belonging to evaluation group ‘rK -‘ developed significantly higher relative body weight gains compared to group ‘rK +’ (p = 0.004). Similar results were found for animals of group ‘Kok-Kat 2’ (p = 0.002) and a statistical tendency was calculated for group ‘Kok-Kat 1’ (p = 0.059) in comparison to group ‘rK -‘. Analogous to the differences in dairy calves animals on fattening farms without relevant oocyst excretion (‘rK -’) had significantly higher relative body weight gains compared to calves of evaluation group ‘rK +’ (p = 0.039) and animals of group ‘Kok-Kat 1’ (p = 0.029) of the same breeds and farms. Nine different Eimeria spp. were detected during the prevalence studies. In single individual samples a minimum of one and up to nine different species were found. Twelve Eimeria spp. are known to be endemic in Europe of which only E. brasiliensis, E. bukidnonensis and E. wyomingensis were not present in any faecal sample in this study. E. bovis and E. zuernii were only second to E. ellipsoidalis which had the highest prevalence (20.99 %) as well as the highest intensity (765963.37 mean opg) in the faecal samples examined. In breeding farms E. ellipsoidalis was the first species to be found in faecal examination in most cases, followed by E. auburnensis and the pathogenic species E. zuernii and E. bovis. E. canadensis and E. pellita were detected only in a low number of samples. E. pellita was observed for the first time at the faecal samplings five weeks after stabling and mainly in farms situated in the central and southern region of the prevalence study. E. canadensis and E. cylindrica were most prominent in farms situated in Belgium and France. Variances in prevalence of the species observed are in conformity with those to be found in recent literature according to the different regions of Europe. This may indicate a representative character of the farms participating in this study and therefore universal validity of the results and impactfactors on coccidiosis in calves described in this manuscript.