Wolbachia are widespread obligate intracellular bacteria that are maternally transmitted and modulate reproduction of their invertebrate host. Mosquitoes transinfected with Wolbachia have reduced capacity for transmitting vector borne diseases and can replace native populations in the field because of a reproductive advantage. The cellular mechanisms of how reproduction is altered by Wolbachia are poorly understood. In this work Wolbachia-induced reproductive changes in the model organism Drosophila were used to pinpoint underlying cellular processes affected by the bacteria. Specifically, egg production (or fecundity) of Wolbachia-infected Drosophila mauritiana was compared to non-infected flies that had been generated by antibiotic treatment of infected flies. Immediately before the fecundity experiment backcrossing of both fly lines ensured an equivalent nuclear genetic background. Initially egg production in Wolbachia-infected flies was increased by 4-fold but in less than 30 generations this changed to a 0.84 fold decrease with a slight advantage for the non-infected line. Additional backcrossing experiments determined that selection on the host nuclear genome is one of the factors underlying this reversion of fecundity gains. Other non-Mendelian factors, such as the microbiota, may also play a role in this rapid change. Wolbachia alterations in egg production were always linked to Wolbachia induced changes in programmed cell death (PCD) in the germarium during oogenesis and germline stem cell (GSC) division. Germline stem cells are maintained and regulated through their interaction with the germline stem cell niche (GSCN). Interestingly, these cells are both frequently infected with Wolbachia and possess a high bacterial titer. A developmental time course revealed the mechanism of how Wolbachia accumulate in the niche cells. The data suggest that the bacteria actually coordinate their replication with the differentiation of the niche cells. Future work on understanding the cellular and molecular basis of Wolbachia - host interaction will not only give insight into novel mechanisms of host manipulation by a pathogen, but will also expand our current understanding of stem cell niche morphogenesis and modulation of stem cell proliferation. / 2018-06-05T00:00:00Z

Laying hen welfare is gaining importance in the United States and several states have passed legislation for a welfareriendly housing environment, which has forced the egg industry to explore alternative housing environments. For this reason, our first objective was to determine the effect of housing environment and laying hen strain on production performance and egg quality. Results showed that production performance of the hens raised in the alternative housing system was similar to the conventional system. The second objective was to compare the eggshell and cloacal microbiology. Our results indicated that the microbial load observed was higher in the alternative system compared to the conventional system. The third objective was to determine the effects of housing environment and laying hen strain on tibia and femur bone properties. The results demonstrated that the alternative system provided better tibia and femur bone characteristics, but it varied among laying hen strains.

No description available.

Plumage damage (PD) as a result of severe feather pecking (SFP) and skin lesions (SL) due to cannibalism (CA) is serious welfare, performance, and economic problems in commercial layer farms. Genetics, nutrition, and housing conditions are central complexes that contribute to the multifactorial causes of these behavioral disorders. Practical recommendations consider the quality of litter as an important criterion for the prevention of SFP, although systematic longitudinal studies providing evidence-based findings are lacking. Therefore, the aim of this study was to investigate the effects of litter condition on the occurrence of PD and SL in the field using a longitudinal design. Integument scoring (PD and SL; 7 times), litter scoring (structure, cake formation, litter quality, and litter height; 12 times), and laboratory litter analysis (dry matter (DM), nitrogen (N), phosphorus (P) and pH value; 12 times) were performed in 28 laying hen flocks with a median flock size of 12,357 birds, in barn (n = 21) or free-range systems (n = 7), during the first laying period. Binary logistic regression (BLR) models showed the association of housing type and animal age on PD and SL (P < 0.001), and of the hybrid type on PD (P < 0.001). Furthermore, a significant association with PD and SL was observed for several litter traits. An increase in litter height, DM, and P was associated with lower PD (P ≤ 0.022) and SL (P < 0.001). In contrast, a higher N content of the litter was associated with an increase in SL (P = 0.007). Cake formation (P < 0.001) and a low structure (P = 0.025) of the litter showed an association with higher PD. In conclusion, this study identified caked litter with less structure, low height, and low contents of DM and P as risk factors for behavioral disorders in commercial laying flocks.

The objective of this study was to investigate the role of fine (F) and coarse (C) limestone ratios and exogenous phytase at standard and superdosing activity on performance, egg quality, and bone quality of post-peak and late-lay Hy-Line W-36 hens. For post-peak, treatments with 40F:60C at 0 and 400 FTU/kg (standard phytase activity) increased hen-day egg production (HDEP). Treatments with 15F:85C decreased feed intake (FI) but also increased unsaleable eggs (UE) and eggshell-breaking strength (EBS). Treatments with 0 and 400 FTU/kg increased albumen quality and treatments with 1500 FTU/kg increased bone quality and phytate breakdown. For late-lay, interaction effects of limestone and phytase were observed for FI, HDEP, UE, bone, and egg quality. Treatments with 40F:60C decreased UE and increased EBS and bone mineral content of aluminum (Al). Treatments with 0 FTU/kg increased eggshell proximate of phosphorus (P) and gizzard pH, but 400 and 1500 FTU/kg increased phytate breakdown and bone quality.

Conventional housing environments for broiler chickens and commercial laying hens are often barren, high-density environments with an emphasis on production efficiency. These housing conditions limit birds' ability to display species-specific behaviors, can negatively impact health, and may contribute to negative cumulative experience. Cumulative experience is the culmination of all positive and negative experienced during an animal's lifetime. However, cumulative experience is difficult to quantify, as no validated measures of cumulative experience exist. Additionally, existing measures of negative animal experience mostly rely on interpretations of animal behavior which can be subjective, time consuming, and difficult to interpret. Therefore, there is scientific need for objective measures that can detect cumulative experience in poultry. Secretory and plasma Immunoglobulin A (IgA), telomere length, feather corticosterone concentrations, and attention bias testing all seem to respond to positive and negative experiences in humans or other non-human animal species, indicating that they may be useful as measures for poultry. Therefore, the objective of this thesis was to determine if these novel measures could be used as indicators of cumulative experience in broiler chickens and laying hens. In chapter 3, secretory and plasma IgA concentrations were measured in broilers raised in either high-complexity or low-complexity environments under either high or low stocking density over three replicated experiments. Birds housed in highly complex environments showed higher concentrations of plasma IgA compared to birds housed in low-complexity environments at day 48 of age, indicating reduced chronic stress in the former. Additionally, day 48 secretory IgA concentrations were decreased in birds housed in high-density environments compared to birds housed in low density environments, indicating birds from high-density environments were more chronically stressed. In chapter 4, gonad and kidney telomere length was measured to determine cumulative experience in broilers raised in the same housing conditions and replicated experiments of chapter 3. Treatment did not impact gonad telomere length, in line with expectations as gonads contain stem cells which produce high concentrations of telomerase. Birds housed in high-complexity pens had longer kidney telomeres compared to birds in low-complexity pens, indicating high-complexity birds had more positive cumulative experience. Stocking density did not impact kidney telomere length. In chapter 5, attention bias, tonic immobility, plasma and secretory IgA concentrations, and feather corticosterone concentrations were determined in laying hens raised in conventional cages or enriched floor pens. Birds in enriched floor pens showed increased attention bias, decreased tonic immobility, increased secretory IgA concentrations at week 22 of age, and decreased feather corticosterone concentrations compared to caged hens. These results indicate that compared to conventional cages, enriched pens in this study improved immune systems, reduced chronic stress, reduced fear, but increased anxiety in hens. In conclusion, secretory and plasma IgA and telomere length show appropriate contrast in response to broiler chicken housing conditions. However, additional work needs to be done before these measures can be widely used as measures of cumulative experience in poultry. Furthermore, attention bias, secretory IgA, and feather corticosterone showed an appropriate contrast between chronic stress responses in laying hens, but confirmation is needed in other contexts. Overall, the results indicate a beneficial relationship between environmental complexity and poultry welfare physiology and affective state, with the exception for anxiety in laying hens. Thus, providing an enriched environment can improve the welfare of commercial poultry and result in positive cumulative experience in most situations. Additionally, these results indicate that stocking density is a negative environment in broilers but potentially less intense than previously thought under experimental conditions. The assessment of behavioral and physiological measures of cumulative and positive animal experience should be included in experiments seeking to determine the impacts of environmental or management conditions to determine the broader impacts on poultry welfare. / Doctor of Philosophy / Conventional housing systems of broiler chickens (raised for meat) and laying hens (raised for egg production) can negatively impact their welfare. Animal welfare, defined as an animal's ability to interact with and cope with their environment, is an individual experience for each animal and fluctuates on a scale from very negative to very positive. Traditionally, measurements of animal welfare have focused only on avoiding the negative aspects of animal welfare such as fear, distress (negative stress), hunger, thirst, pain, and suffering. However, it is important that animals are provided opportunities to experience positive animal welfare to provide a life worth living. So, when measuring animal welfare, all positive and negative experiences (termed cumulative experience) should be included to form an accurate picture of an animal's welfare. However, no validated measures of cumulative experience exist in non-human animals. However, recently, several potential measures of cumulative experience have been proposed in human and non-human animals including secretory and plasma IgA, telomere length, feather corticosterone, and attention bias testing. So, the objective of this thesis was to determine if these proposed measures can be used to determine cumulative experience in commercial broilers and laying hens. In chapters 3 and 4, we investigated if secretory and plasma IgA concentrations (measure of chronic stress; chapter 3) and telomere length (measure of cumulative experience; chapter 4) responded to environmental complexity (positive stimulus) and stocking density (negative stimulus) over three replicated experiments. Broilers were housed in a 2 × 2 factorial study of either high or low complexity or high or low density. This resulted in four treatment groups of high-complexity/high-density, low-complexity/low-density, high-complexity/low-density, and low-complexity/high-density. During chapter 3, environmental complexity increased concentrations of plasma IgA, indicating that birds from high-complexity pens were under less chronic stress compared to birds from low-complexity pens. Alternatively, high density decreased secretory IgA, indicating that birds from high-density pens were under a more chronic stress than birds from low density pens. In chapter 4, environmental complexity increased telomere length in broilers compared to low-complexity pens indicating that environmental complexity positively impacted cumulative experience. However, stocking density did not impact telomere length, indicating that high density did not negatively impact cumulative experience. In chapter 5, we investigated if attention bias (measure of anxiety), tonic immobility duration (measure of fear), plasma and secretory IgA (chronic stress), and feather corticosterone (chronic stress) responded to environmentally enriched floor pens (positive housing system) and conventional caging (negative housing system). We found that birds housed in enriched floor pens were more anxious (increased attention bias), less fearful (decreased tonic immobility duration), and less chronically stressed (increased SIgA concentrations at week 22 and increased feather corticosterone concentrations) compared to birds housed in conventional cages. Overall, IgA concentrations and telomere length (broilers) and attention bias, secretory IgA concentration, and feather corticosterone concentrations (layers) seem useable as measures of animal experience in commercial poultry. Additionally, these results indicate that positive experience has a positive impact on cumulative experience in commercial poultry. Stocking density also seems to contribute to chronic stress in broilers, indicated by decreased SIgA concentrations, but only during the last few weeks of life. These findings should be confirmed by additional studies before common use as measures of cumulative experience in animals. However, the inclusion of measures of cumulative and positive animal experience should be included in experiment which wish to determine the broad impacts of housing system on non-human animals.

Submitted by Johnny Rodrigues (johnnyrodrigues@ufcg.edu.br) on 2018-06-18T13:31:40Z No. of bitstreams: 1 NERANDI LUIZ CAMERINI - TESE PPGEA 2012..pdf: 21432695 bytes, checksum: 7578d920d7cb372f971f067d26250bb6 (MD5) / Made available in DSpace on 2018-06-18T13:31:40Z (GMT). No. of bitstreams: 1 NERANDI LUIZ CAMERINI - TESE PPGEA 2012..pdf: 21432695 bytes, checksum: 7578d920d7cb372f971f067d26250bb6 (MD5) Previous issue date: 2012 / Capes / O objetivo geral desta pesquisa foi avaliar o bem-estar de aves poedeiras em dois diferentes sistemas de criação: gaiola enriquecida (GE) e sistema alternativo (SA) e a qualidade desses sistemas no que diz respeito aos aspectos comportamentais, fisiológicos e produtivos. O experimento foi desenvolvido na câmara climática do LaCRA - Laboratório de Construções Rurais e Ambiência, da Universidade Federal de Campina Grande - PB. A pesquisa constou de três períodos experimentais de 28 dias cada. Foram utilizadas 72 aves poedeiras da linhagem Dekalb White com 27 semanas de idade. O regime de luz adotado foi de 16 horas claro e 8 horas de escuro. O delineamento experimental adotado foi o inteiramente casualizado em esquema fatorial 2x3 (dois sistemas de criação e três condições ambientais (20 °C, 26 °C e 32 °C) com seis repetições e umidade relativa de 60%. A pesquisa analisou diferentes parâmetros: produção; aspectos fisiológicos; desempenho zootécnico; qualidade dos ovos e termografia. Técnicas de processamento e análise de imagens podem vir a colaborar com a busca de informações contidas em imagens de animais confinados. Os dois sistemas de criação utilizados nesta pesquisa não apresentaram grandes diferenças quanto as variáveis analisadas. O sistema de gaiola enriquecida e o sistema alternativo podem ser compatíveis no desempenho e na qualidade dos ovos produzidos. / The general objective of this research was to evaluate the welfare of laying hens in two different systems: Enriched Cage (EC) and Alternative System (AS) and the quality of these systems in relation of behavioral, physiological and productive aspects. The experiment was conducted in a climatic chamber of LaCRA - Laboratory of Rural Constructions and Ambience, in the Federal University of Campina Grande - Paraíba State, Brazil. The research consisted of three experimental periods of 28 days each one. It was used 72 birds of lineage Dekalb White at 27 weeks of age. The light regime was set at 16 hours light and 8 hours of darkness. The experimental design was completely randomized in 2x3 factorial (two creation systems and three environmental conditions: 20 °C, 26 °C and 32 °C) with six replicates and relative humidity of 60%. This research analyzed different parameters: production; physiological aspects; zootechnical performance; egg quality and thermography. Processing techniques and image analysis may come to contribute to the search for information contained in images of confined animais. Both creation systems used in this study showed no large differences in the variables analyzed. Both systems may be compatible in performance and quality of eggs produced.

The diploma thesis deals with the design of an additional device for the application of glass grid rolls GlasGrid® and functional calculations. Diploma thesis was created in collaboration with company Saint-Gobain ADFORS. The designed equipment must be able to lay all the currently produced sizes of the rolls, connectable to the widest possible range of laying machines and must be possible to transport the equipment over a longer distance. The laying equipment must also comply with the strength analysis and functional calculations.

Die Vorteile des Systems „Horn“ gegenüber dem Gangbahn-Flügelrad System liegen in der faserschonenden und lageparallelen Flechtfadenverlegung sowie in der gesteigerten Flechtgeschwindigkeit. Die Herausforderung um das Potential des Systems „Horn“ zur Herstellung von Preforms durch Überflechten zu erschließen, bestand in der Integration eines dritten Fadensystems in eine antriebstechnisch umsetzbare Verlegetechnik zur Fertigung einer triaxialen Flechtstruktur. Für die Synthese dieser Antriebstechnik zur kinematisch optimalen Verlegung der Flechtfäden wurde eine prozessorientierte Synthesemethodik, auf Basis einer Technologiesynthese, erarbeitet. / Advantages of the system “Horn” versus the horn gear motion system lie in a gentle and parallel processing of the braiding materials as well as in an increased speed of braiding. The challenge in extrapolating the potential of the system “Horn” for the production of preforms by over-braiding was to integrate a third yarn system into a laying technique that is technically feasible for processing a triaxial braided structure. For the synthesis of this drive technology and to guarantee an optimal kinematic transfer of threads, a process-oriented synthesizing method, based on a technology synthesis, was elaborated.

Diploma thesis "Media covering of laying-off and unemployed in Lidove noviny during 1. half-year 1930 and in Mlada Fronta DNES during 2. half-year 2008 - Comparison of two approaches" compares reactions of forenamed newspapers to expansion of economic depression which forces employers to reduce cost of production and cost of labour force. Diploma thesis compares the influence of the rate of unemployement in various regions to their representation in medias and also compares the influence of the rate of unemployment in various sectors of economy to their representation in medias. Diploma thesis also analyses subjects of business news which concerned the problem of unemployment.