title: Investigating molecular approaches for detection of pathogens in horses

authors: Grout, Emily Katherine

subjects: Polymerase chain reaction

abstract: Infectious disease of equines has significant impacts on the New Zealand equine industry, causing avoidable morbidity and mortality. The correct identification of the aetiological agents involved in such infections allows for prompt and accurate administration of an appropriate therapeutic strategy, reducing the economic impact associated with equine wastage.  
 
Traditional culturing methods are widely used for the diagnosis of infections in horses, however, conventional PCR offers a novel and rapid approach, through the targeting of unique genes for diagnosis of pathogens. PCR is an attractive alternative to microbial culturing, which can take anywhere between 24 hours to 1 week to determine the causative infectious agent, and in a number of cases the results are not as specific or as accurate as they need to be. It is the lack of sensitivity of the traditional culturing techniques that continues to contribute to the economic loss and welfare issues associated with equine infections.  
 
Initially, it was found that an SDS lysis extraction method worked best for extraction of DNA which was used to extract microbial DNA from various types of clinical samples. These were subsequently used as DNA templates within PCR alongside primers associated with up to 28 genes associated with common equine infections. From a total 146 clinical samples received for testing 66.4% returned a PCR positive for one or more microbial genera, whereas traditional bacteriological culturing produced an identification rate of 46%. In addition, PCR was significantly faster than culturing methods (6 hours vs 48 hours) and allowed more specific identification of the microbes present, which provides a significant advantage for infection management and increasing animal welfare. 
 
The results found from these experiments show rapid PCR identification holds promise as a diagnostic technique in the future, however, further development is required before this can be used as a primary diagnostic technique. Recommendations include further research into trends of infection in NZ equines and respectively increasing the diversity of PCR primers to represent the larger scope of microbial species. PCR diagnosis would also benefit from the standardisation of the DNA extraction methods used to allow consistency and increase throughput of various samples. Lastly, the simplification of the individual PCRs for each infectious agent could be developed into multiplex reactions to decrease time processing time and reduce human pipetting error.

text: Investigating molecular approaches for detection of pathogens in horses Infectious disease of equines has significant impacts on the New Zealand equine industry, causing avoidable morbidity and mortality. The correct identification of the aetiological agents involved in such infections allows for prompt and accurate administration of an appropriate therapeutic strategy, reducing the economic impact associated with equine wastage.  
 
Traditional culturing methods are widely used for the diagnosis of infections in horses, however, conventional PCR offers a novel and rapid approach, through the targeting of unique genes for diagnosis of pathogens. PCR is an attractive alternative to microbial culturing, which can take anywhere between 24 hours to 1 week to determine the causative infectious agent, and in a number of cases the results are not as specific or as accurate as they need to be. It is the lack of sensitivity of the traditional culturing techniques that continues to contribute to the economic loss and welfare issues associated with equine infections.  
 
Initially, it was found that an SDS lysis extraction method worked best for extraction of DNA which was used to extract microbial DNA from various types of clinical samples. These were subsequently used as DNA templates within PCR alongside primers associated with up to 28 genes associated with common equine infections. From a total 146 clinical samples received for testing 66.4% returned a PCR positive for one or more microbial genera, whereas traditional bacteriological culturing produced an identification rate of 46%. In addition, PCR was significantly faster than culturing methods (6 hours vs 48 hours) and allowed more specific identification of the microbes present, which provides a significant advantage for infection management and increasing animal welfare. 
 
The results found from these experiments show rapid PCR identification holds promise as a diagnostic technique in the future, however, further development is required before this can be used as a primary diagnostic technique. Recommendations include further research into trends of infection in NZ equines and respectively increasing the diversity of PCR primers to represent the larger scope of microbial species. PCR diagnosis would also benefit from the standardisation of the DNA extraction methods used to allow consistency and increase throughput of various samples. Lastly, the simplification of the individual PCRs for each infectious agent could be developed into multiplex reactions to decrease time processing time and reduce human pipetting error.

year: 2018

title: Effect of spacers on axial capacity of cold-formed steel back-to-back gapped channel sections

authors: Divi, Seshagiri Rao

abstract: The use of cold-formed steel (CFS) gapped back-to-back channel sections is becoming popular, especially in New Zealand and South-East Asia. Introducing a gap between the back-to-back channels enhances resistance to lateral-torsional buckling. Previous research has investigated gapped built-up channel sections with spacers but hasn't determined the optimal number of spacers relative to length. Also, little attention has been given to how transverse spacing affects the axial capacity of these sections. This study fills those gaps by developing and validating a non-linear elastoplastic finite element (FE) model against experimental data. A parametric study of 1000 FE models examine the effects of column length, CFS section thickness, materials properties, and spacer spacing, on the axial capacity of gapped built-up columns. Key findings include: (1) Up to a column length of 4000 mm, three equally spaced spacers optimize compressive strength in gapped sections. (2) Optimal transverse spacing aligns with the channel web depth, offering no significant strength increase beyond 1.5 times the web depth. (3) Gapped sections show a substantial average increase (424%) in compressive strength over single-channel configurations, and a moderate improvement (125%) compared to non-gapped built-up sections. (4) FEA results closely match the predictions of AS/NZS4600:2018, differing by only 5% in compressive strength.

text: Effect of spacers on axial capacity of cold-formed steel back-to-back gapped channel sections The use of cold-formed steel (CFS) gapped back-to-back channel sections is becoming popular, especially in New Zealand and South-East Asia. Introducing a gap between the back-to-back channels enhances resistance to lateral-torsional buckling. Previous research has investigated gapped built-up channel sections with spacers but hasn't determined the optimal number of spacers relative to length. Also, little attention has been given to how transverse spacing affects the axial capacity of these sections. This study fills those gaps by developing and validating a non-linear elastoplastic finite element (FE) model against experimental data. A parametric study of 1000 FE models examine the effects of column length, CFS section thickness, materials properties, and spacer spacing, on the axial capacity of gapped built-up columns. Key findings include: (1) Up to a column length of 4000 mm, three equally spaced spacers optimize compressive strength in gapped sections. (2) Optimal transverse spacing aligns with the channel web depth, offering no significant strength increase beyond 1.5 times the web depth. (3) Gapped sections show a substantial average increase (424%) in compressive strength over single-channel configurations, and a moderate improvement (125%) compared to non-gapped built-up sections. (4) FEA results closely match the predictions of AS/NZS4600:2018, differing by only 5% in compressive strength.

year: 2024

title: Hapū data sovereignty: Tips for getting started

authors: Clark, Vanessa

abstract: This brief is a part of a series, produced for the Tikanga in Technology (TiNT) research programme, that provides a hapū perspective on data sovereignty, data governance, and data privacy. The purpose is to provide practical advice for individuals, whānau, marae and hapū who are embarking on their own hapū data sovereignty kaupapa, with a particular focus on whakapapa data.

text: Hapū data sovereignty: Tips for getting started This brief is a part of a series, produced for the Tikanga in Technology (TiNT) research programme, that provides a hapū perspective on data sovereignty, data governance, and data privacy. The purpose is to provide practical advice for individuals, whānau, marae and hapū who are embarking on their own hapū data sovereignty kaupapa, with a particular focus on whakapapa data.

year: 2025-02-11