Orientador: Elizabeth Moreira dos Santos Schmidt / Resumo: A coccidiose é uma das doenças mais importantes que acometem leitões lactentes no Brasil. A administração de toltrazuril é usada no mundo todo para a prevenção de coccidiose em leitões, entretanto, não foram encontradas pesquisas sobre a correta profilaxia da doença no Brasil. Sendo assim, este estudo tem como objetivo investigar diferentes protocolos de administração de toltrazuril (FARMACOX® 5%, suspensão oral, Farmabase Saúde Animal, SP, Brasil) sob as condições de campo no estado de São Paulo. Para isso, 495 leitões foram aleatoriamente divididos em quatro diferentes grupos: 125 leitões (grupo controle) que não receberam toltrazuril; 127 leitões que receberam toltrazuril no terceiro dia de vida (grupo dois); 116 leitões que receberam toltrazuril no quinto dia de vida (grupo três), e 127 leitões que receberam duas doses de toltrazuril, uma com três e outra com sete dias de idade (grupo quatro). A excreção de oocistos foi avaliada por análises coproparasitológicas quando os animais tinham cinco, sete, 12, 21 e 63 dias de idade e as pesagens individuais foram realizadas aos três, 21 e 132 dias de idade. Os dados foram analisados usando o peso ao terceiro dia como uma covariável independente. Os resultados foram separados por médias e ajustados por Tukey (p ≤ 0,05). Os animais dos grupos dois e quatro não excretaram Cystoisospora suis, mas um animal do grupo controle e um do grupo três (aos 63 dias de idade) excretaram oocistos de C. suis. Os leitões do grupo controle apresen... (Resumo completo, clicar acesso eletrônico abaixo) / Mestre

Over one third of the human population is currently infected by one or more species of parasitic helminth, but the immune responses elicited by these infections remain poorly defined. Studies in helminth-exposed human populations and laboratory models suggest that helminth infection elicits a range of different effector cell types and that protective immunity and resistance to immune-mediated pathology depends on the balance between these responses. The aim of this thesis was to investigate how cytokines, the molecular mediators of the immune system, can be used to characterise human immune phenotype during natural and experimental helminth infection. Cytokines associated with innate inflammatory (TNFα, IL-6 and IL-9), Thl (IFNγ, IL-2 and IL-12p70), Th2 (IL-4, IL-5 and IL-13), Th17 (IL-17A, IL-21 and IL-23) and regulatory (IL-10 and TGFβ)immune phenotypes were analysed to provide the most comprehensive analysis of cytokine responses in human helminth infection conducted to-date. Using a multivariate statistical approach cytokines were analysed as combined immune profiles to reflect their complex interactions in vivo. In the first part of the study venous blood samples collected from a cross-sectional cohort of 284 Zimbabweans (age range: 3 -86 years) endemically-exposed to Schistosoma haematobium were cultured with antigens from different stages of the parasite's life-cycle(cercariae, adult worms and eggs) and the anti-schistosome vaccine candidate antigen glutathionine-S-transferase (GST). Cytokines responses were quantified in culture supernatants via enzyme-linked immunosorbent assay (ELISA). These assays were repeated 6 weeks after clearance of infection by anti-helminthic treatment. Parasitological and demographic characterisation of the cohort before, 6 weeks, 6 and 18 months after treatment allowed cytokine responses to be related to epidemiological patterns of infection before treatment and the risk of re-infection after treatment. The main findings of this study were:Cytokine responses to the antigens of S. haematobium cercariae are more proinflammatory than those elicited by adult worms and eggs prior to treatment, reflecting the distinct proteomes and exposure patterns of the 3 life-cycle stages Young children (5-10 years old) have a more regulatory and Th17-polarised cytokine response to S. haematobium antigens than older children and adults. These responses are significantly associated with schistosome infection intensity and may contribute to the development of resistance to schistosomiasis with age and exposure to infection Anti-helminthic treatment leads to a shift in S. haematobium cercariae, egg and GST specific cytokine responses towards a more pro-inflammatory phenotype The magnitude of change in S. haematobium-specific cytokine profiles after treatment is dependent on schistosome infection intensity at the time of treatment Individuals who remain un-infected up to 18 months after treatment to clear schistosome infection have a more pro-inflammatory and IL-21-polarised response to S. haematobium antigens 6 weeks after treatment than those who become re-infected, suggesting that post-treatment cytokine profiles promote resistance to re-infection. The second part of the study assayed systemic, parasite and allergen-specific cytokine responses in 45 adults with seasonally exacerbated allergy to grass pollen who were experimentally exposed to Trichuris suis. Cytokine responses in infected individuals were compared to those of 44 un-infected controls. This aspect of the study showed that: Exposure to T. suis promotes systemic and parasite-specific Th2 and regulatory cytokine responses, but does not alter cytokine responses to environmental allergens.

Feldstudie zum Einsatz gezielter Desinfektionsmaßnahmen gegen die Saugferkelkokzidiose Institut für Parasitologie der Veterinärmedizinischen Fakultät der Universität Leipzig Eingereicht im März 2004 Schlüsselworte: Saugferkelkokzidiose, Isospora suis, Bekämpfung, Desinfektion, Ne-opredisan 135-1® 109 Seiten, 13 Abbildungen, 12 Tabellen, 137 Literaturangaben, 11 Anhangstabellen Die neonatale Kokzidiose des Schweins ist ein weit verbreitetes Problem in Ferkelerzeugerbe-trieben, das üblicherweise durch medikamentelle Metaphylaxe bekämpft wird. Aufgabe der hier vorliegenden Arbeit war es, eine gezielte Desinfektion mit Neopredisan 135-1®, einem gegen Kokzidienoozysten wirksamen Desinfektionsmittel, als mögliche Alternative zur medi-kamentellen Bekämpfung zu testen. In zwei Ferkelerzeugerbetrieben im Landkreis Diepholz (Niedersachsen) mit vorberichtlicher Isosporoseproblematik wurden von Oktober 2001 bis Juli 2002 in sechs Versuchsdurchgän-gen (V1 bis V6) insgesamt 56 Würfe (Gruppe A) nach einer Eingangsdesinfektion und zu-sätzlicher Desinfektion in der belegten Abferkelbox mit Neopredisan 135-1® auf Isospora suis koproskopisch und klinisch untersucht und mit 50 Würfen, die als Kontrollgruppe (Grup-pe B) geführt wurden, verglichen. In der Versuchsgruppe (Gruppe A) wurde einmal (V1 und Gruppe A1 in V5) gegen Ende der ersten Lebenswoche, zweimal (V2, Gruppe A2 in V5, V6) gegen Ende der ersten und zweiten Lebenswoche oder dreimal (V3 und V4) gegen Ende der ersten Lebenswoche und erneut zwei und vier Tage später eine Desinfektion durchgeführt. Die Würfe wurden ab dem 5. Lebenstag siebenmal bis zum Absetzen nach der dritten Le-benswoche untersucht, wobei jeweils vier Ferkeln pro Wurf Einzelkotproben rektal entnom-men und die beprobten Ferkel klinisch beurteilt wurden. Durchfallkotproben wurden differen-tialdiagnostisch auf andere Enteropathogene (E. coli, Clostridien, Salmonellen, Lawsonia intracellularis, Brachyspira hyodysenteriae) untersucht. Am ersten und letzten Untersu-chungstermin wurden die Ferkel jeweils gewogen. Von den Muttersauen wurden am ersten und letzten Untersuchungstermin eines Versuchsdurchganges Kotproben parasitologisch un-tersucht. In V3 war aufgrund einer mangelhaft durchgeführten Reinigung erwartungsgemäß keine Des-infektionswirkung zu verzeichnen, und dieser Versuchsdurchgang wurde nicht weiter ausge-wertet. Mit Ausnahme von V6 waren die Befallsraten der Würfe mit Isospora suis in den zu-sätzlich desinfizierten Buchten geringer als bei den Kontrollen. Bezogen auf die Einzelproben waren in allen fünf ausgewerteten Versuchsdurchgängen in der Gruppe A insgesamt weniger Proben positiv als in der Kontrollgruppe B. Dabei schwankten die Befallsraten der Würfe in den einzelnen Versuchsdurchgängen zwischen 14 % und 90 % in der Gruppe A und zwischen 43 % und 83 % in der Gruppe B. Mit einer einmaligen Zwischendesinfektion war eine Reduk-tion der Prävalenz von Isospora suis um 67 % bis 77 % erreichbar. Die zweimalige Desinfek-tion reduzierte das Auftreten von I. suis um 54 %, 71 % und 83 % und die dreimalige Zwi-schendesinfektion um 76 %. Somit hat die Zwischendesinfektion zwar den Infektionsdruck senken können, die Wirkung konnte aber nicht durch eine erhöhte Frequenz der Desinfektion verbessert werden. Insgesamt hatten 7 % der Proben Durchfallcharakter. In V1, V2 und V5 waren dabei in der Gruppe A weniger Würfe betroffen als in der Kontrollgruppe B, in V4 und V6 konnte ein entsprechender Effekt nicht festgestellt werden. Die Durchfallraten der Würfe schwankten in den einzelnen Versuchsdurchgängen zwischen 43 % und 90 % in der Gruppe A und zwischen 60 % und 90 % in der Gruppe B. Bezogen auf die Ferkel war eine Reduktion des Auftretens von Durchfall außer in V2 regelmäßig erreichbar. Mit einer einmaligen Zwischendesinfektion konnte die Durchfallhäufigkeit um 43 % und 65 % reduziert werden, mit zweimaliger Desin-fektion um 18 % und 48 % und mit dreimaliger Desinfektion um 39 %. Die Durchfallhäufig-keit konnte insgesamt durch die Zwischendesinfektion reduziert werden, aber auch hier brach-te eine erhöhte Frequenz der Desinfektion keinen zusätzlichen Nutzen. Auf weitere klinische Parameter sowie die Gewichtsentwicklung der Ferkel hatte die Zwi-schendesinfektion wenig bis gar keinen Einfluss. Bei den Sauen waren in wenigen Fällen Eier von Magen-Darm-Strongyliden sowie Oozysten von Eimerien nachweisbar. Oozysten von I. suis konnten hier nicht gefunden werden. Die Ergebnisse zeigen unter Feldbedingungen einen hemmenden Einfluss von Neopredisan 135-1® auf die Ausbreitung der Isosporose, so dass in einer gezielten Desinfektion ein zur Metaphylaxe alternativer Ansatz für eine Bekämpfung liegen könnte. Allerdings ist in Be-ständen mit bestehender klinischer Problematik eine alleinige Desinfektion nicht ausreichend, so dass hier eine Kombination von medikamenteller Metaphylaxe und Desinfektion vorge-schlagen wird. Möglichkeit und Nutzen von integrierten Bekämpfungsmaßnahmen, die ein parasitologisch-klinisches Monitoring einschließen müssen, sollten in weiteren Studien unter-sucht werden. / Field study concerning the suitability of disinfection in fighting piglet coccidiosis for Institute of Parasitology, Faculty of Veterinary Medicine, University of Leipzig Submitted in March 2004 Keywords: Piglet coccidiosis, Isospora suis, Control, Disinfection, Neopredisan 135-1® 109 pages, 13 figures, 12 tables, 137 references, 11 appendices Piglet coccidiosis is a well-known and frequent problem in piglet production. It is usually fought by metaphylaxis. The objective of this investigation was to try specific disinfection with Neopredisan 135-1® for the control of coccidiosis as an alternative approach to medica-tion. Between October 2001 and July 2002, 56 litters (group A) kept in pens that were additionally disinfected after farrowing with Neopredisan 135-1® were compared to 50 litters (group B) without disinfection. The study was performed in six sequences (V1 to V6) on two piglet breeding farms with a history of Isosporosis (Diepholz, Lower Saxony). In group A, addi-tional disinfection was conducted at the end of the first week of life (V1 and group A1 in V5), a second, additional disinfection at the end of the first and second week of life (V2, group A2 in V5, V6) and three additional disinfections were made at the end of the first week of life and two and four days later (V3 and V4). Litters were examined seven times from the fifth day after farrowing until weaning. Individual faecal samples from four piglets per litter were col-lected. Each piglet was examined clinically. Subjects with diarrhea were assayed for Entero-bacteriaceae for differential diagnosis. On the first and the last examination day piglets were weighed. Samples from the sows were examined for parasites on the first and the last exami-nation day. Sequence V3 was discarded because of insufficient stall cleanliness, which, as expected, re-sulted in failure of disinfection. In general, the prevalence of Isospora suis was lower in the litters where repeated disinfections were conducted than in the litters without additional disin-fection with the exception of V6. I. suis was discovered more often in the individual samples from group B than from group A in all five trial sequences. The prevalence in the litters ranged from 14 % to 90 % in group A and from 43 % to 83 % in group B. A single additional disinfection reduced the prevalence of I. suis by 67 % to 77 %, two additional disinfections reduced the prevalence of I. suis by 54 %, 71 % and 83 % and three additional disinfections reduced the prevalence of I. suis by 76 %. Thus disinfection after farrowing is suited to reduce the infection pressure, however increased frequency of additional measures did obviously not improve the hygienic status. Diarrhea was diagnosed in 7 % of all subjects. In the sequences V1, V2 and V5, more litters in group B showed diarrhea than in group A. In the sequences V4 and V6 there were equal numbers of litters with diarrhea in both groups. The prevalence of diarrhea in the litters was ranging from 43 % to 90 % in group A and from 60 % to 90 % in group B. Related to the in-dividual piglets diarrhea was less frequently seen in group A. A single additional disinfection reduced the prevalence of diarrhea by 43 % and 65 %, two additional disinfections reduced the prevalence of diarrhea by 18 % and 48 % and three additional disinfections reduced the prevalence of diarrhea by 39 %. However, in trial sequence V2 (repeated disinfection) no re-duction of the prevalence of diarrhea was observed. Disinfection after farrowing is suited to reduce the prevalence of diarrhea, but no improvement can be seen by increased frequency of additional measures. Other clinical aspects, such as weight gain, were not influenced by additional disinfection. In the samples from the sows eggs of Strongyloides and oocysts of Eimeria were occasionally seen, oocysts of I. suis were not found. The present data show that Neopredisan 135-1® can inhibit the spread of piglet coccidiosis under field conditions. Specific disinfection may be a suitable control measure against piglet coccidiosis. In case of clinical coccidiosis, disinfection alone will not suffice but may support medical metaphylaxis. More investigations are required to explore the suitability of integrated control measures that should include parasitological monitoring.

Thesis (Ph.D.)--University of Wollongong, 2009. / Typescript. Includes bibliographical references: leaf 188-214.

Submitted by GIOVANI MARCO STINGELIN null (giovani_44@hotmail.com) on 2017-04-19T04:16:09Z No. of bitstreams: 1 Dissertação de Mestrado Giovani M. Stingelin.pdf: 1323487 bytes, checksum: 714dbbed6afc25d765018a23a47264a0 (MD5) / Approved for entry into archive by Luiz Galeffi (luizgaleffi@gmail.com) on 2017-04-19T13:55:36Z (GMT) No. of bitstreams: 1 stingelin_gm_me_bot.pdf: 1323487 bytes, checksum: 714dbbed6afc25d765018a23a47264a0 (MD5) / Made available in DSpace on 2017-04-19T13:55:36Z (GMT). No. of bitstreams: 1 stingelin_gm_me_bot.pdf: 1323487 bytes, checksum: 714dbbed6afc25d765018a23a47264a0 (MD5) Previous issue date: 2017-03-09 / A coccidiose é uma das doenças mais importantes que acometem leitões lactentes no Brasil. A administração de toltrazuril é usada no mundo todo para a prevenção de coccidiose em leitões, entretanto, não foram encontradas pesquisas sobre a correta profilaxia da doença no Brasil. Sendo assim, este estudo tem como objetivo investigar diferentes protocolos de administração de toltrazuril (FARMACOX® 5%, suspensão oral, Farmabase Saúde Animal, SP, Brasil) sob as condições de campo no estado de São Paulo. Para isso, 495 leitões foram aleatoriamente divididos em quatro diferentes grupos: 125 leitões (grupo controle) que não receberam toltrazuril; 127 leitões que receberam toltrazuril no terceiro dia de vida (grupo dois); 116 leitões que receberam toltrazuril no quinto dia de vida (grupo três), e 127 leitões que receberam duas doses de toltrazuril, uma com três e outra com sete dias de idade (grupo quatro). A excreção de oocistos foi avaliada por análises coproparasitológicas quando os animais tinham cinco, sete, 12, 21 e 63 dias de idade e as pesagens individuais foram realizadas aos três, 21 e 132 dias de idade. Os dados foram analisados usando o peso ao terceiro dia como uma covariável independente. Os resultados foram separados por médias e ajustados por Tukey (p ≤ 0,05). Os animais dos grupos dois e quatro não excretaram Cystoisospora suis, mas um animal do grupo controle e um do grupo três (aos 63 dias de idade) excretaram oocistos de C. suis. Os leitões do grupo controle apresentaram menor peso ao desmame quando comparado com os do grupo quatro. Quando os leitões do grupo controle tinham 132 dias de idade, o peso corporal foi significativamente menor quando comparado com os grupos dois e quatro. Os animais do grupo controle tiveram menor ganho de peso diário (GPD) que os do grupo quatro no período de três a 21 dias e menor GPD dos três aos 132 dias de idade que os animais dos grupos dois e quatro. Estes resultados sugeriram que a administração de toltrazuril ao terceiro dia de vida é o protocolo recomendado para controle da coccidiose e para melhoria do peso e GPD dos leitões. / Coccidiosis is one of the most important diseases affecting suckling piglets. It causes diarrhea, dehydration, weight loss, low performance and significant economic losses. Toltrazuril administration is used worldwide for coccidiosis prevention in piglets, however, no research was found on the correct prophylaxis of the disease in field conditions in Brazil. Thus, this study is aimed at evaluating different protocols of toltrazuril administration (FARMACOX® 5%, oral suspension, Farmabase Animal Health, SP, Brazil). These protocols were used for specific conditions of production in the state of São Paulo for controlling coccidiosis under field conditions. For that, 495 piglets were randomly allocated. The animals were divided into four different groups: 125 piglets (control group) which did not receive toltrazuril; 127 piglets that received toltrazuril on the third day of life (group two); 116 piglets which received toltrazuril on the fifth day (group three), and 127 piglets that received two dosages of toltrazuril when the animals were 3 and 7 days-old (group four). Excretion of oocysts was evaluated by coproparasitological analysis when the animals were 5, 7, 12, 21 and 63 days-old. They were individually weighed at 3, 21 and 132 days-old to evaluate the growth performance between treatments. Data was analyzed using the MIXED procedure of SAS, using the third day weight as an independent covariate. Results were separated with PDIFF adjusted by Tukey (P ≤ 0.05). Groups 2 and 4 did not excrete C. suis. One animal from the control group and group three (63 days-old) excreted C. suis oocysts. The control group demonstrated lower weight at weaning when compared to group 4. When the piglets from the control group were 132 days-old the body weight was significant lower when compared to groups 2 and 4. The control group also demonstrated significant lower average daily weight gain (ADG) then group 4 at weaning and lower significant ADG at 132 days-old then groups 2 and 4. These results suggested that the administration of toltrazuril by the third day of life is the recommended protocol to control coccidiosis and to improve the weight and ADG of piglets.

Two species of Cryptosporidium are routinely found in pigs: Cryptosporidium suis and Cryptosporidium pig genotype II. Identification of Cryptosporidium species and genotypes currently relies on molecular methods such as polymerase chain reaction (PCR) followed by restriction fragment lenght polymorphism (RFLP) or gene sequencing. However their applications are limited in identification of mixed infections. To overcome this problem, novel species specific primers were developed in this study. A total of 457 pig fecal samples were collected and examined using microscopy and molecular tools including PCR-RFLP, species or genus specific nested PCR and sequencing. Of these, 12.8 % were microscopicaly positive for oocysts presence and 36.5 % using molecular methods. While PCR-RFLP with genus specific primers revealed 1 case of C. suis and Cryptosporidium pig genotype II mixed infection only, nested PCR with species specific primers identified 41 cases of mixed infections. Our results showed that C. suis is infectious for all age categories of pigs and Cryptosporidium pig genotype II has been found in animals older than 6 weeks of age. Morphometric analysis proved oocyst size difference between both pig specific Cryptosporidium spp. Histological examination revealed that Cryptosporidium pig genotype II infects epithelia of both small and large intestine.

Mémoire numérisé par la Direction des bibliothèques de l'Université de Montréal.

Feldstudie zum Einsatz gezielter Desinfektionsmaßnahmen gegen die Saugferkelkokzidiose Institut für Parasitologie der Veterinärmedizinischen Fakultät der Universität Leipzig Eingereicht im März 2004 Schlüsselworte: Saugferkelkokzidiose, Isospora suis, Bekämpfung, Desinfektion, Ne-opredisan 135-1® 109 Seiten, 13 Abbildungen, 12 Tabellen, 137 Literaturangaben, 11 Anhangstabellen Die neonatale Kokzidiose des Schweins ist ein weit verbreitetes Problem in Ferkelerzeugerbe-trieben, das üblicherweise durch medikamentelle Metaphylaxe bekämpft wird. Aufgabe der hier vorliegenden Arbeit war es, eine gezielte Desinfektion mit Neopredisan 135-1®, einem gegen Kokzidienoozysten wirksamen Desinfektionsmittel, als mögliche Alternative zur medi-kamentellen Bekämpfung zu testen. In zwei Ferkelerzeugerbetrieben im Landkreis Diepholz (Niedersachsen) mit vorberichtlicher Isosporoseproblematik wurden von Oktober 2001 bis Juli 2002 in sechs Versuchsdurchgän-gen (V1 bis V6) insgesamt 56 Würfe (Gruppe A) nach einer Eingangsdesinfektion und zu-sätzlicher Desinfektion in der belegten Abferkelbox mit Neopredisan 135-1® auf Isospora suis koproskopisch und klinisch untersucht und mit 50 Würfen, die als Kontrollgruppe (Grup-pe B) geführt wurden, verglichen. In der Versuchsgruppe (Gruppe A) wurde einmal (V1 und Gruppe A1 in V5) gegen Ende der ersten Lebenswoche, zweimal (V2, Gruppe A2 in V5, V6) gegen Ende der ersten und zweiten Lebenswoche oder dreimal (V3 und V4) gegen Ende der ersten Lebenswoche und erneut zwei und vier Tage später eine Desinfektion durchgeführt. Die Würfe wurden ab dem 5. Lebenstag siebenmal bis zum Absetzen nach der dritten Le-benswoche untersucht, wobei jeweils vier Ferkeln pro Wurf Einzelkotproben rektal entnom-men und die beprobten Ferkel klinisch beurteilt wurden. Durchfallkotproben wurden differen-tialdiagnostisch auf andere Enteropathogene (E. coli, Clostridien, Salmonellen, Lawsonia intracellularis, Brachyspira hyodysenteriae) untersucht. Am ersten und letzten Untersu-chungstermin wurden die Ferkel jeweils gewogen. Von den Muttersauen wurden am ersten und letzten Untersuchungstermin eines Versuchsdurchganges Kotproben parasitologisch un-tersucht. In V3 war aufgrund einer mangelhaft durchgeführten Reinigung erwartungsgemäß keine Des-infektionswirkung zu verzeichnen, und dieser Versuchsdurchgang wurde nicht weiter ausge-wertet. Mit Ausnahme von V6 waren die Befallsraten der Würfe mit Isospora suis in den zu-sätzlich desinfizierten Buchten geringer als bei den Kontrollen. Bezogen auf die Einzelproben waren in allen fünf ausgewerteten Versuchsdurchgängen in der Gruppe A insgesamt weniger Proben positiv als in der Kontrollgruppe B. Dabei schwankten die Befallsraten der Würfe in den einzelnen Versuchsdurchgängen zwischen 14 % und 90 % in der Gruppe A und zwischen 43 % und 83 % in der Gruppe B. Mit einer einmaligen Zwischendesinfektion war eine Reduk-tion der Prävalenz von Isospora suis um 67 % bis 77 % erreichbar. Die zweimalige Desinfek-tion reduzierte das Auftreten von I. suis um 54 %, 71 % und 83 % und die dreimalige Zwi-schendesinfektion um 76 %. Somit hat die Zwischendesinfektion zwar den Infektionsdruck senken können, die Wirkung konnte aber nicht durch eine erhöhte Frequenz der Desinfektion verbessert werden. Insgesamt hatten 7 % der Proben Durchfallcharakter. In V1, V2 und V5 waren dabei in der Gruppe A weniger Würfe betroffen als in der Kontrollgruppe B, in V4 und V6 konnte ein entsprechender Effekt nicht festgestellt werden. Die Durchfallraten der Würfe schwankten in den einzelnen Versuchsdurchgängen zwischen 43 % und 90 % in der Gruppe A und zwischen 60 % und 90 % in der Gruppe B. Bezogen auf die Ferkel war eine Reduktion des Auftretens von Durchfall außer in V2 regelmäßig erreichbar. Mit einer einmaligen Zwischendesinfektion konnte die Durchfallhäufigkeit um 43 % und 65 % reduziert werden, mit zweimaliger Desin-fektion um 18 % und 48 % und mit dreimaliger Desinfektion um 39 %. Die Durchfallhäufig-keit konnte insgesamt durch die Zwischendesinfektion reduziert werden, aber auch hier brach-te eine erhöhte Frequenz der Desinfektion keinen zusätzlichen Nutzen. Auf weitere klinische Parameter sowie die Gewichtsentwicklung der Ferkel hatte die Zwi-schendesinfektion wenig bis gar keinen Einfluss. Bei den Sauen waren in wenigen Fällen Eier von Magen-Darm-Strongyliden sowie Oozysten von Eimerien nachweisbar. Oozysten von I. suis konnten hier nicht gefunden werden. Die Ergebnisse zeigen unter Feldbedingungen einen hemmenden Einfluss von Neopredisan 135-1® auf die Ausbreitung der Isosporose, so dass in einer gezielten Desinfektion ein zur Metaphylaxe alternativer Ansatz für eine Bekämpfung liegen könnte. Allerdings ist in Be-ständen mit bestehender klinischer Problematik eine alleinige Desinfektion nicht ausreichend, so dass hier eine Kombination von medikamenteller Metaphylaxe und Desinfektion vorge-schlagen wird. Möglichkeit und Nutzen von integrierten Bekämpfungsmaßnahmen, die ein parasitologisch-klinisches Monitoring einschließen müssen, sollten in weiteren Studien unter-sucht werden. / Field study concerning the suitability of disinfection in fighting piglet coccidiosis for Institute of Parasitology, Faculty of Veterinary Medicine, University of Leipzig Submitted in March 2004 Keywords: Piglet coccidiosis, Isospora suis, Control, Disinfection, Neopredisan 135-1® 109 pages, 13 figures, 12 tables, 137 references, 11 appendices Piglet coccidiosis is a well-known and frequent problem in piglet production. It is usually fought by metaphylaxis. The objective of this investigation was to try specific disinfection with Neopredisan 135-1® for the control of coccidiosis as an alternative approach to medica-tion. Between October 2001 and July 2002, 56 litters (group A) kept in pens that were additionally disinfected after farrowing with Neopredisan 135-1® were compared to 50 litters (group B) without disinfection. The study was performed in six sequences (V1 to V6) on two piglet breeding farms with a history of Isosporosis (Diepholz, Lower Saxony). In group A, addi-tional disinfection was conducted at the end of the first week of life (V1 and group A1 in V5), a second, additional disinfection at the end of the first and second week of life (V2, group A2 in V5, V6) and three additional disinfections were made at the end of the first week of life and two and four days later (V3 and V4). Litters were examined seven times from the fifth day after farrowing until weaning. Individual faecal samples from four piglets per litter were col-lected. Each piglet was examined clinically. Subjects with diarrhea were assayed for Entero-bacteriaceae for differential diagnosis. On the first and the last examination day piglets were weighed. Samples from the sows were examined for parasites on the first and the last exami-nation day. Sequence V3 was discarded because of insufficient stall cleanliness, which, as expected, re-sulted in failure of disinfection. In general, the prevalence of Isospora suis was lower in the litters where repeated disinfections were conducted than in the litters without additional disin-fection with the exception of V6. I. suis was discovered more often in the individual samples from group B than from group A in all five trial sequences. The prevalence in the litters ranged from 14 % to 90 % in group A and from 43 % to 83 % in group B. A single additional disinfection reduced the prevalence of I. suis by 67 % to 77 %, two additional disinfections reduced the prevalence of I. suis by 54 %, 71 % and 83 % and three additional disinfections reduced the prevalence of I. suis by 76 %. Thus disinfection after farrowing is suited to reduce the infection pressure, however increased frequency of additional measures did obviously not improve the hygienic status. Diarrhea was diagnosed in 7 % of all subjects. In the sequences V1, V2 and V5, more litters in group B showed diarrhea than in group A. In the sequences V4 and V6 there were equal numbers of litters with diarrhea in both groups. The prevalence of diarrhea in the litters was ranging from 43 % to 90 % in group A and from 60 % to 90 % in group B. Related to the in-dividual piglets diarrhea was less frequently seen in group A. A single additional disinfection reduced the prevalence of diarrhea by 43 % and 65 %, two additional disinfections reduced the prevalence of diarrhea by 18 % and 48 % and three additional disinfections reduced the prevalence of diarrhea by 39 %. However, in trial sequence V2 (repeated disinfection) no re-duction of the prevalence of diarrhea was observed. Disinfection after farrowing is suited to reduce the prevalence of diarrhea, but no improvement can be seen by increased frequency of additional measures. Other clinical aspects, such as weight gain, were not influenced by additional disinfection. In the samples from the sows eggs of Strongyloides and oocysts of Eimeria were occasionally seen, oocysts of I. suis were not found. The present data show that Neopredisan 135-1® can inhibit the spread of piglet coccidiosis under field conditions. Specific disinfection may be a suitable control measure against piglet coccidiosis. In case of clinical coccidiosis, disinfection alone will not suffice but may support medical metaphylaxis. More investigations are required to explore the suitability of integrated control measures that should include parasitological monitoring.

The Chlamydiaceae are widespread pathogens of both humans and animals. Chlamydia trachomatis infection causes blinding trachoma and reproductive complications in humans. Chlamydia pneumoniae causes human respiratory tract infections and atypical pneumonia. Chlamydia suis infection is associated with conjunctivitis, diarrhea, and failure to gain weight in domestic swine. Chlamydial infections in humans and domesticated animals are generally controlled by antibiotic treatment—particularly macrolides (usually azithromycin) and tetracyclines (tetracycline and doxycycline). Tetracycline-containing feed has also been used to limit infections and promote growth in livestock populations, although its use has decreased because of growing concerns about antimicrobial resistance development. Because Sandoz and Rockey published an elegant review of chlamydial anti-microbial resistance in 2010, we will review the following: (i) antibiotic resistance in C. suis, (ii) recent evidence for acquired resistance in human chlamydial infections, and (iii) recent non-genetic mechanisms of antibiotic resistance that may contribute to treatment failure.

Thèse numérisée par la Direction des bibliothèques de l'Université de Montréal.