Avian Influenza virus M2e protein: Epitope mapping, competitive ELISA and phage displayed scFv for DIVA in H5N1 serosurveillance

Within the avian influenza virus (AIV) history, H5N1 subtype is the most alarming in terms of its spread rate throughout the globe with its demonstrated unusual pattern of evolution. Persistency and constant circulation of this subtype in poultry population in a number of countries have resulted its establishment and declaration as enzootic. The affected countries are commonly characterised by high poultry populations and productions. They are also developing countries which have minimal funding allocated for precaution on disease incursion. Past observations showed that a single AIV epizootic is capable of causing significant economic burden throughout the world. Although epizootic, it still resulted sporadic cases of human infection and mortality. Therefore, H5N1 enzootic countries opt for vaccination strategy (usually with inactivated whole virus) to evade AIV incursions. However, this interferes with the AIV surveillance effort. This is due to the lack of diagnostic tool with the ability to differentiate AIV infected animal from vaccinated animal (DIVA). Following this realisation, several options are made available. Diagnostic tool development which is capable of DIVA requires a highly sensitive and specific target which at the same time is economic, and pose ease of application. In recent years, growing interest on the AIV matrix 2 extracellular domain (M2e) protein has propelled its exploration as the target for AIV serosurveillance diagnostic tool development. It has been demonstrated to be highly sensitive and specific in detection for AIV infection in an indirect enzyme-linked immunosorbent assay (ELISA) setting. The factor which made it highly interesting is its ability for DIVA application. M2e protein can only be found in low concentration on an AIV particle which is used in an inactivated vaccination strategy, while present in high concentration if cells are AIV infected. Therefore, this study has further explores the AIV M2e protein potential for AIV serosurveillance diagnostic tool development and successfully demonstrated an M2e-based test in a competitive ELISA format for DIVA. This particular ELISA format was of interest as it can be potentially used in multiple species application, as AIV is a multispecies pathogen. To ensure the universality of the competitor antibody, comparative mapping of anti-M2e antibodies from chicken, mouse and rabbit was done. Findings highlighted slight variations in the epitope identified for the M2e antigen by antibodies from different species. Mouse anti-M2e antibodies are more suitable to be used as the competitor antibodies against anti-M2e chicken sera in the M2e-based competitive ELISA test. Consequently, application of the mouse anti-M2e antibodies in the M2e-based competitive ELISA has demonstrated specific and sensitive indication of AIV infection in the H5N1 challenged chicken sera. Biotechnology developments has also introduced the single chain variable fragment (scFv) antibodies as specific and stable bait for antibodies detection against targeted pathogen’s protein (antigen). Taking advantage of this knowledge, this study has also successfully isolated reactive and specific anti-M2e scFv antibodies from avian sources. This is critical as an avian sourced antibodies to be used as bait for the targeted pathogen’s protein is highly relevant in the setting for AIV serosurveillance application in the poultry industry. These findings are significant in the effort to provide a highly sensitive and specific diagnostic tool, which are also cost effective, easy to apply with high throughput ability. Such ideal diagnostic tool for AIV serosurveillance is highly valuable, as this may hold the key to break the AIV continuous circulation.Thesis (Ph.D.) -- University of Adelaide, School of Animal and Veterinary Sciences, 201

First description of male worms of Enterobius (Colobenterobius) serratus (Nematoda: Oxyuridae), the pinworm parasite of proboscis monkeys

Males of Enterobius (Colobenterobius) serratus Hasegawa et al., 2003 (Nematoda: Oxyuridae) are described for the first time based on six individuals collected from the feces of proboscis monkeys, Nasalis larvatus, in the Lower Kinabatangan Wildlife Sanctuary, Sabah, Malaysian Borneo. The males show identical cephalic morphology to females, being readily distinguishable from their congeners by the serrated inner margins of the lips. The bicolored esophageal corpus, long thin spicule and developed spicular pouch with paired muscular bands are also remarkable characteristics, presumably shared by other Asian members of the subgenus

The experience of traditional massage practitioners in supporting breastfeeding practice

Strategies that have been successful in promoting breastfeeding practice and to increase breastfeeding education include mother-to-mother support and close contact with breastfeeding support members through home visits. The objective of this study is to explore the experience of traditional massage practitioners in promoting and supporting breastfeeding practice. A qualitative study using semi structured face-to-face interview was conducted among breastfeeding support group members who are working as traditional massage practitioners. The data was transcribed and analyzed using thematic analysis. Three themes were revealed involving participants real enjoyed the experiences, gaining knowledge on breastfeeding technique and breastfeeding challenges. This study identified that the traditional massage practitioners have shown good support towards breastfeeding practice and recommended the need of massage therapy for continuity of this practice

Challenging ecogeographical rules: Phenotypic variation in the Mountain Treeshrew (Tupaia montana) along tropical elevational gradients

Bergmann’s and Allen’s rules were defined to describe macroecological patterns across latitudinal gradients. Bergmann observed a positive association between body size and latitude for endothermic species while Allen described shorter appendages as latitude increases. Almost two centuries later, there is still ongoing discussion about these patterns. Temperature, the common variable in these two rules, varies predictably across both latitude and elevation. Although these rules have been assessed extensively in mammals across latitude, particularly in regions with strong seasonality, studies on tropical montane mammals are scarce. We here test for these patterns and assess the variation of several other locomotory, diet-associated, body condition, and thermoregulatory traits across elevation in the Mountain Treeshrew (Tupaia montana) on tropical mountains in Borneo. Based on morphological measurements from both the field and scientific collections, we found a complex pattern: Bergmann’s rule was not supported in our tropical mountain system, since skull length, body size, and weight decreased from the lowest elevations (<1000 m) to middle elevations (2000–2500 m), and then increased from middle elevations to highest elevations. Allen’s rule was supported for relative tail length, which decreased with elevation, but not for ear and hindfoot length, with the former remaining constant and the latter increasing with elevation. This evidence together with changes in presumed diet-related traits (rostrum length, zygomatic breadth and upper tooth row length) along elevation suggest that selective pressures other than temperature, are playing a more important role shaping the morphological variation across the distribution of the Mountain Tree shrew. Diet, food acquisition, predation pressure, and/or intra- and inter-specific competition, are some of the potential factors driving the phenotypic variation of this study system. The lack of variation in body condition might suggest local adaptation of this species across its elevational range, perhaps due to generalist foraging strategies. Finally, a highly significant temporal effect was detected in several traits but not in others, representing the first phenotypic variation temporal trends described on tree shrews

First description of male worms of Enterobius (Colobenterobius) serratus (Nematoda: Oxyuridae), the pinworm parasite of proboscis monkeys

Males of Enterobius (Colobenterobius) serratus Hasegawa et al., 2003 (Nematoda: Oxyuridae) are described for the first time based on six individuals collected from the feces of proboscis monkeys, Nasalis larvatus, in the Lower Kinabatangan Wildlife Sanctuary, Sabah, Malaysian Borneo. The males show identical cephalic morphology to females, being readily distinguishable from their congeners by the serrated inner margins of the lips. The bicolored esophageal corpus, long thin spicule and developed spicular pouch with paired muscular bands are also remarkable characteristics, presumably shared by other Asian members of the subgenus

Fungi from dead arthropods and bats of Gomantong cave, northern Borneo, Sabah (Malaysia)

Borneo is a biodiversity and ecotourism hotspot, yet one of its least-studied ecosystems is their limestone caves. Not many studies have been conducted on the role fungi play in tropical cave ecosystems, and no fungal surveys have been conducted in the caves of Sabah, Malaysia. Here, we assess the mycofloral diversity on bat and arthropod cadavers in one of the most popular ecotourism destinations of northern Borneo, Gomantong caves. Opportunistic sampling of cadavers within the Semud Hitam chamber of Gomantong cave yielded nine dead arthropods and four dead bats. Twenty-four culturable fungi were isolated, of which 14 morphological taxonomic units (MTU) were observed. Twelve of the 14 MTUs underwent molecular characterization of the ITS gene region to confirm identification. All fungi were Ascomycetes except for one Basidiomycete isolate. Aspergillus spp. had the highest occurrence (45.8%), followed by Penicillium spp. (25.0%), and Fusarium sp. (12.5%). Ceratobasidium sp., Diaporthe sp., Pestalotiopsis sp., and Xylaria feejeensis were isolated once each. No more than one fungal taxon was isolated from each arthropod cadaver, and not all arthropods yielded culturable fungi. Bat cadavers yielded 14 out of 24 isolates (58.3%), with the highest occurrence of the fungi sampled from their skin. Our results corroborate that bats and arthropods play a role in fungal dispersion and introduction in the cave because their exteriors are likely to harbor fungi they are exposed to in the environment. We also conclude that cadavers are important substrates for fungal growth and proliferation, perpetuating the role of fungi as important decomposers in caves. This study provides a baseline of information of the mycobiome of Bornean caves for future bioprospecting and potential biotechnological applications

Bat species diversity trend along an elevation gradient: A study in Crocker Range Park, Sabah, Borneo

Bats (Order: Chiroptera) is a recognised group of bioindicators due to their sensitivity towards alterations in their immediate surroundings. With the threats of climate change becoming more severe on a daily basis, it is reasonable to collect data on how bat diversity is influenced by elevation. This will be useful to predict and monitor possible upslope shifting of bat species due to increase in surrounding temperature or anthropogenic pressure. Hence, this study aims to uncover the bat diversity trend at different elevations in Crocker Range Park (CRP), Sabah, Malaysia. Bat trappings were conducted in four substations within this park, covering an elevation spectrum from 450 to 1900 m a.s.l. The overall sampling managed to capture 133 individuals of bats, predominantly Pteropodidae, with the addition of two new species locality records for CRP, Murina peninsularis and Hypsugo vondermanni. Simple linear regression analyses revealed that both bat diversity and richness have an inverse linear relationship with elevation. Likewise, the Pearson’s correlation value, associating bat diversity with elevation, also shows that they have a negative relationship at r = -0.852. Heterogeneity of habitats explain this trend, as in the lower counterpart of CRP, lowland forests, which are richer in fruit and insect resources persist. Besides, lower land forests have better niche assortment, due to the distinctive layers stratification, allowing bats utilising different guilds to thrive in the same vegetation profile. This study further emphasises the role of CRP to protect most of the bat species found in Borneo, as well as serving as the baseline data for the future studies that look into the impact of temperature increment towards the upslope shifting of the bat population in CRP