Browsing by Author "Binney, Barbara Mary"

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    The major histocompatibility complex (MHC) of the kiwi (Apteryx spp.) : a thesis submitted for the degree of Master of Science (Molecular Biosciences), Massey University, New Zealand, December 2007
    (Massey University, 2007) Binney, Barbara Mary
    This thesis investigates the polymorphism of the Major Histocompatibility Complex (MHC) in the threatened New Zealand Kiwi {Apteryx spp.). The MHC genes are usually highly polymorphic and play a direct role in disease resistance. A lack of MHC polymorphism may affect the ability of a population to respond to continuously evolving pathogens. The Kiwi is a unique bird, endemic to New Zealand, but despite being considered taonga (a treasure) all five kiwi species are threatened and require active management to sustain current population levels. The role of infectious diseases in the kiwi's past and future survival is currently only a matter of conjecture. To analyse the kiwi MHC and its polymorphism, a PCR and primers were designed that amplified the MHC Class II B exon 2, a protein binding region (PBR) and a site where polymorphism is expected. Feather samples from three different kiwi species, the North Island Brown (Apteryx mantelli), the Little Spotted Kiwi (Apteryx owenii), and the Rowi (Apteryx rowi) were used as a non-invasive source of DNA. The MHC results for eight Little Spotted Kiwi from Red Mercury Island showed almost no variation in the form of different alleles between birds. Four putative alleles were shared by all birds, each bird having some or all of the alleles. Rowi are only found in Okarito and are a small population of 250 birds. The 18 birds tested showed a greater range of diversity than expected from a bottled necked population with 14 putative alleles and three pseudogenes. A result more consistent with a remnant population. The twelve North Island Brown birds showed a range of polymorphism: 11 putative alleles and two pseudogenes. Analysis of the Kiwi MHC supports the suggestion that avian MHC sequences evolved by concerted evolution and genetic conversion.
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    The microbial ecology of Campylobacter jejuni in New Zealand within a spatial-temporal framework : a thesis presented in partial fulfilment of requirements for the degree of Doctor of Philosophy in Veterinary Science at Massey University, Manawatu, New Zealand
    (Massey University, 2015) Binney, Barbara Mary
    Campylobacter jejuni (C. jejuni) is an important cause of gastroenteritis internationally; it is a complex bacterium carried by multiple hosts, showing phenotypic and genotypic variation. This thesis systematically examines the molecular ecology and evolution of C. jejuni in New Zealand from the levels of population movement, phenotype, genome and metabolism. First, the demographic history of cattle, sheep and poultry importations into New Zealand (1860- 1979) was quantified. Australia was the most common reported source of cattle sheep and poultry, with large numbers of cattle and sheep being imported in the 1860s, and large numbers of poultry imported from the 1960s onwards. This suggests the population structure of cattle and sheep and the microbial organisms they carried may exhibit a founder effect. The second level investigated the phenotypes of related sequence types (ST) with generalist and specialist lifestyles and compared them at 42°C and 22°C on the basis of carbon source utilisation in Biolog phenotypic microarrays. The isolates utilised a total of 29 carbon sources in a pattern that clustered them together on the basis of ST at 42°C more than lifestyle and host. At 22°C they utilised a limited palette of carbon sources (9) related to the tricarboxylic acid cycle (TCA). The third level, used genomic comparisons to identify a putative new species C. sp. nov. 4 spp. in the Australian purple swamphen (Porphyrio porphyrio melanotus). Overall, the pattern of relationship between isolates associated with the pukeko (Porphyrio porphyrio melanotus), takahe (Porphyrio hochstetteri) and the Australian swamphen isolates suggested a recent common ancestor and then divergence after separation. Despite high levels of recombination in C.jejuni, the genomes grouped by clonal complex and ST, this suggests there are factors restricting regular recombination between more distant C. jejuni STs. The draft genomes for the wild-bird and agricultural-related isolates clustered by lineages in a host(s). The fourth level involved the comparison of C. jejuni metabolic pathways (subsystems) to identify host association. Type VI secretion system, Coenzyme A biosynthesis and Campylobacter spp. iron metabolism were identified as important pathways in distinguishing between wild-bird and livestock associated isolates.