Coccidiosis is endemic in the commercial broiler industry and inflicts devastating economic losses to poultry operations. Probiotics may provide a potential alternative to the prophylactic use of anticoccidials in commercial production. This study evaluated the effects of probiotic applications (feed and water) on bird performance and resistance to a mixed Eimeria infection in commercial broilers. On day of hatch, 1008 commercial male broilers (Cobb 500) were assigned to one of 6 treatments (8 replicate floor pens; 21 birds/pen), including non-infected negative control (NEG), Eimeria-infected positive control (POS), anticoccidial control (0.01% salinomycin, SAL), intermittent high dose water-applied probiotic (WPI), continuous low dose water-applied probiotic (WPC), and feed-supplemented probiotic (FSP). On d15, all birds except those in NEG were challenged with a mixed inoculum of Eimeria acervulina, E. maxima, and E. tenella. Measurements were taken on d7, 15, 21, 28, 35 and 42. Fecal samples were collected from d20-d24 for oocyst counts, and lesion scores were evaluated on d21. Data were analyzed using the Fit Model platform in JMP Pro 10.0 (SAS). Differences in experimental treatments were tested using Tukey HSD following ANOVA with significance reported at P ° 0.05. Overall, NEG birds outperformed all other groups. For performance, the probiotic groups were comparable to the SAL treated birds, except during the 6 days immediately following the Eimeria species challenge, where the SAL birds exhibited better performance. WPC birds had lower duodenal and jejunal lesion scores, indicating a healthier intestine and enhanced resistance to Eimeria species compared to POS. Birds in the WPI treatment shed fewer oocysts in the feces, though this was not a trend for all of the probiotic treatment groups. The results of this study suggest probiotic supplementation without anticoccidials can enhance performance and help alleviate the negative effects of a mixed Eimeria infection. / Master of Science

Excystation of coccidian oocysts is a diphasic process where CO2 and suitable reducing agents cause changes in oocyst wall permeability (phase I) allowing the entrance of trypsin and bile which activate the sporozoites (phase II). This project was an indirect study of the mechanism of CO2 action by the substitution of NO, NO2, N2O, H2S, SO2 , CH4, NH3 and 8M urea in place of CO2. Changes in oocyst wall permeability of Eimeria stiedae, E. bovis and E. tenella were determined by incubation with the reagents and cysteine HCl followed by treatment with trypsin and bile to initiate activation of sporozoites, staining oocyst inner structures with methylene blue, and removal of outer and inner oocyst walls with sodium hypochlorite. The gases CH4 , NO2, N2O were negative for all 3 tests as were SO2, NH3 and 8M urea which in addition were toxic to the oocysts. Both H2S and NO were capable of mimicing the action of CO2 and are related chemically to the reducing agent, and hence tend to underscore its importance in excystation. It now appears that the role of CO2 is that of an allosteric effector enhancing the action of the reducing agent.

No description available.

This thesis examines the costs and benefits of maternal allocation to both mother and offspring in gamebirds, specifically ring necked pheasants (Phasianus colchicus) and the Chinese painted quail (Coturnix chinensis). Maternal allocation of compounds from the mother to the young during early development can potentially have both positive and negative effects. For example the transfer of nutrients to the offspring can help to increase post-partum survival and subsequent life time reproductive success. In contrast, the transfer of stress hormones can potentially have long term negative effects on the offspring’s development. The first part of this thesis investigates the effects of the transfer of immune components from mother to offspring, which are known to have positive short term effects (protection against pathogens in early development). There is therefore considerable interest in whether this response can be induced by maternal vaccination to confer protection to young birds in commercial situations. However, it is unclear how this affects life-history trade offs in the mother and the development of the offspring post-hatching. These effects are especially important in the gamebird industry where birds are commercially reared on a large scale before being released into the wild. Chapter 2 therefore examines the costs and benefits to the mother of producing a maternally transmitted immune response to the CoxAbic vaccine, such as the impact of vaccination on egg laying characteristics and body condition. Chapter 3 looks at these costs and benefits to the chicks by examining growth rates and survival after a challenge of live coccidia in offspring from vaccinated and unvaccinated mothers. Chapter 4 examines the immune response to vaccination in adult pheasants. Finally, chapter 5 considers other factors that have been shown to affect the allocation decisions of females, specifically the effect of male characteristics on female reproductive effort.

Coccidiosis has a negative economic impact on the commercial poultry industry, and probiotics are beneficial bacteria that aid in maintaining healthy gut microflora. We hypothesized that probiotic administration would positively affect gut morphology and increase IgG secretion during an Eimeria challenge, which was evaluated by measuring total chicken IgG and gut morphology (villus height, villus width, villus surface area, crypt depth, villus height to crypt depth ratio and lamina propria thickness). On day-of-hatch, broilers were placed into floor pens with 50 percent pine shavings and 50 percent used litter. The broilers were exposed to Eimeria oocysts via the feed on day 14 and challenged on day 36. On days 6, 22, 36, and 43, tissue samples from the intestine were collected for morphological evaluation, and blood samples were taken to quantify chicken IgG from serum. Data were measured using a factorial ANOVA and main effect means were deemed significant at P ≤ 0.05. In cases where significant interactions were observed, data was subjected to a one-way ANOVA. All means were separated using a Duncan’s Multiple Range Test. On day 6 in the duodenum, a significant interaction was observed regarding vaccination and probiotic administration (Coccivac®-B, Intervet/Schlering-Plough Animal Health/Merck and Co., Inc., Whitehouse Station, NJ). Villus height to crypt depth ratio decreased in ionophore treated birds compared to control birds in the duodenum and lower ileum on day 6, 36, and 43. Villus crypt depth in vaccinated birds decreased in the duodenum after the challenge. On day 43, the ionophore treated birds had less villus height and surface area compared to control and vaccinated birds, while lamina propria thickness increased in the duodenum, and non probiotic birds had longer villi than probiotic birds. On day 22, vaccinated birds had significantly increased chicken IgG levels compared to the control and ionophore birds, and the non probiotic birds had significantly increased IgG secretion compared to probiotic fed birds. On day 36, the ionophore birds had significantly increased levels of IgG compared to the control birds, which could also support that the ionophore delayed exposure to the parasite. These results suggest that gut morphology and humoral immunity are affected by probiotic administration, coccidiosis vaccination, ionophore application and Eimeria challenge. Both the day 43 morphology results and day 36 chicken IgG results for the ionophore treated birds demonstrates that ionophore administration delays exposure of the avian gut to invasive coccidia. More research is necessary to evaluate how probiotics influence coccidiosis vaccination and humoral immunity, so that probiotics may be used to improve the effectiveness of coccidiosis vaccination and to evaluate if probiotics aid in ameliorating the effects of an Eimeria infection.

Two experiments were performed to evaluate effects of amprolium administration at specific times and concentrations in replacement broiler breeders of three genetic lines vaccinated against coccidiosis. Effects on performance parameters including body weight and flock uniformity, and post-vaccination oocyst cycling patterns were evaluated in addition to development of immunity following clinical Eimeria challenge according to gross and microscopic lesion scoring, post-challenge body weight gain (BWG), and total oocyst output. Experiment one was conducted on fresh pine shavings while experiment two was conducted on used litter remaining in treatment pens from the first trial. No significant differences were seen among treatment groups with regard to body weight in either trial. Increased magnitude of oocyst shedding was observed in trial one, Line A with the group receiving amprolium on day 10. Trends in the data indicated increased uniformity in Line A related to amprolium administration following day 21. The group in Line A receiving amprolium at day 10 showed a significantly lower degree of total oocyst output following challenge than the other medicated groups. The group receiving amprolium on day 10 in Line B showed significant reduction in post-vaccination oocyst shedding following treatment in both trials while all shedding was delayed in trial two when compared to the first trial. Effects on uniformity in Line B pullets varied between trials with trends indicating it being advantageous when used litter was a factor. Higher post-challenge BWG was observed in Line B pullets administered the low concentration at day 16 than the controls. Reductions in gross lesion development were seen in Line B pullets in both trials. Line C pullets receiving the highest concentration of amprolium at day 16 showed significantly less uniformity in trial one while the controls appeared to perform better than all medicated groups in trial two. All medicated groups in Line C exhibited delayed and increased magnitudes of oocyst shedding in trial two. These data indicate that the effects of amprolium on performance and immunity development are variable according to genetic strain and indicated that administration may be influenced by litter condition.

Thesis (M.S.)--Auburn University, 2008. / Abstract. Vita. Includes bibliographical references.

Two immunologically distinct strains of poultry coccidium Eimeria maxima, Guelph (GS) and M6 strains, were investigated. Paired in vivo experiments demonstrated that GS and M6 have prepatent periods of approximately 120 h followed by peak oocyst shedding at 144 150 h post inoculation. Fecundity of E. maxima M6 (12.8×103±1.95 oocysts shed/oocyst inoculated) was approximately twice that of GS (6.9×103±3.33) when inoculated with 1×103 infective oocysts per bird. Numerous sequential observations of synchronized populations of oocysts sporulating at 26°C showed no difference in the sporulation kinetics of the two strains; in both strains, sporogony was divided into five morphologically distinguishable stages whose abundance peaked at the following times during sporulation: unsporulated oocysts at 0 h; sporoblast anlagen at 18 h; sporoblasts without sporocyst walls at 22 h; and sporocysts without mature sporozoites at 38 h. Total RNA was isolated from four stages of sporogonic development (18 h, 22 h and 38 h of sporulation, and excysting sporozoites). These RNA samples were quantitatively pooled from each strain separately prior to selection of poly A mRNA that was then fragmented, end-labeled and pyrosequenced using an Illumina HiSeq 2000 sequencer. The resulting transcriptome sequences (~48.8×109bp total reads) were paired and de novo assembled. Ten thousands transcripts (5,000 from each strain) were searched against GenBank using blastx. A total of 2,067 transcripts of GS and 1,610 transcripts of M6 were assigned to putative biological function; ~60% of functionally annotated transcripts mapped to metabolic or cellular processes. GPI anchored surface antigens (SAgs) identified in GS (18 SAgs) and M6 (18 SAgs) belonged to four major multi copy gene families and 2 single copy loci. Relative expression of SAgs expressed by both strains was generally similar; however, 3 GPI-anchored SAgs were uniquely expressed by each of GS and M6. One multigene locus demonstrated strain-specific SAg expression that may explain the lack of cross immunity between these strains. This represents the first transcriptome data of sporulation of E. maxima and first comparison of immunologically distinct strains of any Eimeria sp. These data should aid in the search for antigenic targets that could be included in future subunit vaccines against these important agricultural parasites. / Research Funding: Natural Sciences and Engineering Research Council of Canada (NSERC) and the Ontario Ministry of Agriculture and Food (OMAF); Funding of Studies: Iraqi Ministry of Higher Education and Scientific Research (MOHESR) for PhD scholarship support; American Society of Parasitologists for a Marc Dresden Travel Award to attend the 2012 ASP Annual Meeting.

Orientador: Celio Raimundo Machado / Banca: Urara Kawazoe / Banca: Carlos Wilson Gomes Lopes / Banca: Luis Francisco Prata / Banca: Antonio Carlos Paulillo / Resumo: A infecção experimental por Eimeria stiedae em coelhos foi realizada com o objetivo de avaliar os sinais clínicos, alterações hematológicas, metabólicas e anatomopatológicas. Foram utilizados 50 coelhos, raça Nova Zelândia, brancos, com idade entre 40 - 60 dias e de pesos semelhantes. Os animais foram randomizados com relação ao peso e distribuídos em 2 grupos experimentais: grupo infectado, inoculado com 1ml de solução contendo 1x104 oocistos esporulados de E. stiedae; grupo controle, inoculado 1 ml de água destilada. Os animais foram avaliados semanalmente, durante 28 dias, a partir da data de inoculação. Os dados foram avaliados utilizando-se método estatístico não paramétrico pelo teste de Wilcoxon ao nível de 5% de significância. Coelhos infectados com oocistos esporulados de Eimeria stiedae tiveram cirrose hepática que afetou o funcionamento normal do referido órgão repercutindo em produção de proteínas de fase aguda e ocasionando consideráveis alterações metabólicas. / Abstract: The experimental infection by Eimeria stiedae in rabbits was performed to evaluate the clinical signs, hematological, metabolic and pathological changes. Fifty rabbits were used, New Zealand race, white, aged 40 to 60 days and of similar weight. The animals were randomized to the weight and distributed into 2 experimental groups: infected group, inoculated with 1 ml of solution containing 1x104 sporulated oocysts of Eimeria stiedae; control group, inoculated 1 ml of distilled water. The animals were evaluated weekly, for 28 days from the date of inoculation. A statistical was used non-parametric Wilcoxon test method at 5% level of significance. Rabbits infected with sporulated oocysts of Eimeria stiedae had liver cirrhosis that affected the normal functioning of the body resulting in production of acute phase proteins and cause considerable metabolic changes. / Doutor

Made available in DSpace on 2014-06-11T19:33:26Z (GMT). No. of bitstreams: 0 Previous issue date: 2009-02-02Bitstream added on 2014-06-13T21:06:05Z : No. of bitstreams: 1 freitas_flc_dr_jabo.pdf: 1139081 bytes, checksum: 856bf3c96a6f7eed40da1a35b470f7ae (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A infecção experimental por Eimeria stiedae em coelhos foi realizada com o objetivo de avaliar os sinais clínicos, alterações hematológicas, metabólicas e anatomopatológicas. Foram utilizados 50 coelhos, raça Nova Zelândia, brancos, com idade entre 40 - 60 dias e de pesos semelhantes. Os animais foram randomizados com relação ao peso e distribuídos em 2 grupos experimentais: grupo infectado, inoculado com 1ml de solução contendo 1x104 oocistos esporulados de E. stiedae; grupo controle, inoculado 1 ml de água destilada. Os animais foram avaliados semanalmente, durante 28 dias, a partir da data de inoculação. Os dados foram avaliados utilizando-se método estatístico não paramétrico pelo teste de Wilcoxon ao nível de 5% de significância. Coelhos infectados com oocistos esporulados de Eimeria stiedae tiveram cirrose hepática que afetou o funcionamento normal do referido órgão repercutindo em produção de proteínas de fase aguda e ocasionando consideráveis alterações metabólicas. / The experimental infection by Eimeria stiedae in rabbits was performed to evaluate the clinical signs, hematological, metabolic and pathological changes. Fifty rabbits were used, New Zealand race, white, aged 40 to 60 days and of similar weight. The animals were randomized to the weight and distributed into 2 experimental groups: infected group, inoculated with 1 ml of solution containing 1x104 sporulated oocysts of Eimeria stiedae; control group, inoculated 1 ml of distilled water. The animals were evaluated weekly, for 28 days from the date of inoculation. A statistical was used non-parametric Wilcoxon test method at 5% level of significance. Rabbits infected with sporulated oocysts of Eimeria stiedae had liver cirrhosis that affected the normal functioning of the body resulting in production of acute phase proteins and cause considerable metabolic changes.