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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

The systematics of the anoa (Bubalus sp.) : taxonomy, biogeography and conservation of Sulawesi's endangered buffalo

Burton, James A. January 2005 (has links)
The endangered anoa, Sulawesi's dwarf buffalo, has suffered from unfocused conservation management because of taxonomic uncertainties. Analyses of skull morphology, karyotype, allozymes and mtDNA have produced conflicting results; the current classification identifies two species, the lowland and mountain anoa Bubalus depressicornis and B. quarlesi, respectively. To examine whether distinct phytogenies exist, 92 in situ individuals were sampled from throughout their range (Sulawesi and Buton Islands). Individuals in the zoo population are of unknown origin; eleven animals were included in the analysis to assess the level of genetic variation represented in this population relative to the wild. The assessment of in situ population genetic structure and assignment of ex situ animals was conducted using bovine microsatellite markers and a single mtDNA D-loop sequence. Of the 30 bovine microsatellite markers assessed, 13 amplified and were polymorphic in the anoa and were used in the study. The analysis of microsatellite marker data indicated that anoa populations are structured geographically giving an Fsr = 0.3491. Additional methods corroborated the existence of four geographically distributed subpopulations, including assignment analysis, I lardy-Weinberg equilibrium tests, allelic variation and multivariate analysis. D-loop data corroborated the correlation of anoa population structure and biogeographic regions, but defined three clades. Genetic distances calculated from microsatellite data between pairs of geographically differentiated anoa populations showed similar (δμ)² distances or smaller Nei's distances than those observed between clearly different bovid species (domestic cattle Bos taunis and Mongolian yak B. grunniens). Therefore, using the indicator of dissimilarity species definition there was not clear support for the single or multiple species hypothesis. The genotypic cluster species definition (microsatellite alleles) supported the existence of a single species. In contrast the cohesion species concept (mtDNA) suggested multiple anoa species exist. Therefore, although the previous taxonomic classification was refuted by the lack of a correlation between genetic variation and either species morphotypes or altitude, a new taxonomic status could not be confirmed. Individuals from the zoo population were found to be only partially representative of the wild population; greater genetic variation was found in the Indonesian zoo anoa than the European animals. The population genetic structure was partially explained by isolation by distance (microsatellite and mtDNA) and barriers to gene flow. Microsatellite genetic variation was significantly correlated with the sea barrier between Buton and Sulawesi Islands. In this location the biogeographic barrier acted as a stronger dispersal barrier than predicted by geographic distance alone. However, on Sulawesi Island analyses showed that both known biogeographic barriers and geographic distance contributed to the genetic variation, but tests could not confirm which had the greater effect. The anoa was defined as a single evolutionary significant unit (ESU) because although the genetic exchangeability has been limited there was a lack of regional ecological adaptation. Conservation strategies of in situ anoa should maintain gene flow between networks of protected populations to preserve a minimum viable population (MVP).
2

Physical aspects of heat storage in the ox, (Bos taurus)

Watts, Paul Roderick January 1977 (has links)
No description available.
3

Univariate and multivariate statistical methods in the investigation of growth and shape - with special reference to the bovine ox

MacFie, H. J. H. January 1977 (has links)
No description available.
4

The natural history, non-invasive sampling, activity patterns and population genetic structure of the Bornean banteng Bos javanicus lowi in Sabah, Malaysian Borneo

Gardner, Penny January 2014 (has links)
The banteng (Bos javanicus lowi) is an endangered wild bovid that is endemic to the island of Borneo. Within their last stronghold, the Malaysian state of Sabah, their population is believed to be less than 500 individuals, which are threatened with extinction by habitat loss and hunting. The banteng is highly elusive and rarely seen, and their preference for dense and remote tropical forest habitat makes them a highly challenging species to study. No extensive quantitative surveys have been undertaken in Sabah, and there is little information available to underpin their conservation and management. This thesis provides the first baseline data on the Bornean banteng in Sabah using ecological and molecular techniques. In Chapter 2, I created the first extensive natural history account of the banteng, which will help further the knowledge of this species. This compilation helped identify gaps in the knowledge, which were then addressed by this thesis. In Chapter 3, I test non-invasive survey techniques and individual identification, and estimate the population size in two forest reserves. In Chapter 4, I demonstrate that logged forests undergo dramatic changes in structure and ambient temperature, and that banteng mitigate these changes by altering their behaviour to avoid thermal-stress. Chapter 5 presents new information of the population genetic structure of banteng in four forest reserves in Sabah. Using mitochondrial markers I show that the ancestral lineage of the Bornean banteng reinforces the suggestion that they should be recognised as a separate subspecies to the Burmese and Javan banteng. I also show that the banteng experienced a population expansion following their colonisation of Borneo, and that the present genetic diversity indicates the population may be managed as two geographically-distinct units. Chapter 6 summarises the main findings of this thesis and the implications for the conservation of the Bornean banteng in Sabah.

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