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1	The relative importance of natural and human-induced environmental conditions for species richness distribution patterns in South Africa Hugo, Sanet 19 November 2008 (has links) I studied the spatial distribution of South African avian species richness from the viewpoint that humans are a substantial modifying force on earth, and have also modified the historical spatial distribution of species richness. The main aim of the thesis is to investigate the way in which humans have modified avian species richness patterns in South Africa at the quarter-degree square (QDS) resolution, which is a phenomenon that has been either overlooked, or not completely clarified, in many previous studies of the same region and data at the same resolution. In particular, I investigated hypotheses that were proposed to explain the maintenance of a positive relationship between native species richness and human population density in the face of negative human impacts. Further, I investigated which of the possible anthropogenic and natural environmental factors determine spatial distribution in exotic bird species. Highlighted from these studies are that substantial positive and negative human influences on bird species richness distribution patterns are observable at the QDS resolution, that there are differences between common native birds and rare native birds with regard to their relationships with anthropogenic environmental conditions and exotic bird species, and that the particular combination of environmental covariates that is important for the spatial distributions of exotic species is taxon- and scale-dependent. Even though these results have contributed much towards our understanding on how human modifications have affected species richness patterns, this thesis leaves some unanswered questions. Finer resolution studies and temporal studies are needed to examine many of these questions. Further, an interdisciplinary approach incorporating politics and economics into ecological studies is needed to enhance our understanding of the factors that modify the distribution of humans and their associated threats and benefits to species richness. / Dissertation (MSc)--University of Pretoria, 2010. / Zoology and Entomology / unrestricted South african avian species richness UCTD
2	Development of Novel Genome Editing in Avian Species: Functional Genomic Studies for Melanophilin and Myostatin Genes Lee, Joonbum 15 September 2022 (has links) No description available. Genetics Animal Sciences CRISPR/Cas9 genome editing avian species adenovirus melanophilin myostatin
3	Development of Novel High-Resolution Melting (HRM) Assays for Gender Identification of Caribbean Flamingo (Phoenicopterus ruber ruber) and other Birds Chapman, Alexandra 14 March 2013 (has links) Unambiguous gender identification (ID) is needed to assess parameters in studies of population dynamics, behavior, and evolutionary biology of Caribbean Flamingo (Phoenicopterus ruber ruber) and other birds. Due to its importance for management and conservation, molecular (DNA-based) avian gender ID assays targeting intron-size differences of the Chromosome Helicase ATPase DNA Binding (CHD) gene of males (CHD-Z) and females (CHD-W) have been developed. Male (ZZ) and female (WZ) genotypes are usually scored as size polymorphisms through agarose or acrylamide gels. For certain species, W-specific restriction sites or multiplex polymerase chain-reaction (PCR) involving CHD-W specific primers are needed. These approaches involve a minimum of three steps following DNA isolation: PCR, gel electrophoresis, and photo-documentation, which limit high throughput scoring and automation potential. In here, a short amplicon (SA) High-resolution Melting Analysis (HRMA) assay for avian gender ID is developed. SA-HRMA of an 81-Base Pair (bp) segment differentiates heteroduplex female (WZ) from homoduplex male (ZZ) genotypes by targeting Single-nucleotide Polymorphisms (SNPs) instead of intron-size differences between CHD-Z and CHD-W genes. To demonstrate the utility of the approach, the gender of Caribbean Flamingo (P. ruber ruber) (17 captive from the Dallas Zoo and 359 wild from Ria Lagartos, Yucatan, Mexico) was determined. The assay was also tested on specimens of Lesser Flamingo (P. minor), Chilean Flamingo (P. chilensis), Saddle-billed Stork (Ephippiorhynchus senegalensis), Scarlet Ibis (Eudocimus ruber), White-bellied Stork (Ciconia abdimii), Roseate Spoonbill (Platalea ajaja), Marabou Stork (Leptoptilos crumeniferus), Greater Roadrunner (Geococcyx californianus), and Attwater's Prairie Chicken (Tympanuchus cupido attwateri). Although the orthologous 81 bp segments of Z and W are highly conserved, sequence alignments with 50 avian species across 15 families revealed mismatches affecting one or more nucleotides within the SA-HRMA forward or reverse primers. Most mismatches were located along the CHD-Z gene that may generate heteroduplex curves and thus gender ID errors. For such cases, taxon and species-specific primer sets were designed. The SA-HRMA gender ID assay can be used in studies of avian ecology and behavior, to assess sex-associated demographics and migratory patterns, and as a proxy to determine the health of the flock and the degree by which conservation and captive breeding programs are functioning. endangered birds gender of sexually monomorphic birds sexually monomorphic birds fledglings nestlings DNA test to sex birds Attwater's Prairie Chicken Accipiter species Ría Lagartos Biosphere Reserve Lesser Flamingo Flamingo Chilean Flamingo Phoenicopterus ruber ruber Phoenicopterus Caribbean Flamingo High-resolution Melting Analysis CHD1-W CHD1-Z polymorphism W chromosome Z chromosome CHD1 gene CHD gene gender of birds sex determination of birds gender determination of birds multiple avian species non-invasive conservation of birds sex-ratio of birds sex determination molecular avian gender molecular gender determination Universal sexing of non-ratite birds

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