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    Investigations on black soldier fly (Hermetia illucens L.) production and nutrition : a sustainable solution for poultry feeding : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Animal Science, School of Agriculture and Environment, College of Sciences, Massey University, Palmerston North 4442, New Zealand
    (Massey University, 2024-08-20) Mahmoud, Amira Elsayed Abdalla
    Black soldier fly (BSF; Hermetia illucens L.) is renowned for efficiently converting organic wastes into valuable biomass rich in protein and fat. This makes it a profitable and sustainable method for waste management and a useful feed source for animals like poultry, fish, pigs, and pets. Using BSF reduces the dependence on traditional feed ingredients such as soybean and fish meal, which are often imported and add to the carbon footprint. Despite growing interest and large-scale production of BSF meals, knowledge gaps hinder the widespread adoption of this technology, especially in small and medium-scale operations. The overall aim of this multidisciplinary research was to better understand the biology and rearing methods of BSF, processing of insect meals, and their utilisation by broiler chickens. The thesis research specifically investigated: (1) methods and techniques that optimise BSF breeding and meal processing relevant to small and medium-sized operations, (2) the impact of substrate type, moisture, and compaction on the non-feeding stages of BSF, (3) disease management in BSF colonies to ensure healthy population dynamics, including the first record of red mites as a parasitic case within BSF colonies, and (4) the nutritional value of the larval and pre-pupal stages of BSF as replacements for soybean meal (SBM) in poultry feeds. Firstly, the thesis provided a practical guide to establishing and managing a BSF colony, covering the entire process from egg production to larval and pre-pupal meal processing. The procedures were based on the experience of producing 450 kg of BSF larvae (BSFL) and pre-pupae (BSFP) over the course of doctoral research. Secondly, a study examined the impacts of substrate type, moisture levels, and compaction on BSF pupation success, adult emergence and morality. Among the six substrates evaluated (sand, wood shavings, topsoil, vermiculite, spent wheat middlings, and potting soil), spent wheat middlings presented as the most cost-effective and readily available option. Moisture level was found to significantly affect substrate performance, with 10% moisture providing the best outcomes for pupation and reducing mortality while avoiding mould growth. Mild compaction did not negatively impact pupation development, suggesting that moderate compaction could enable small farmers to reuse substrate and lower the cost. Thirdly, an infestation of poultry red mites (Dermanyssus gallinae), causing noticeable skin discoloration and anatomical damage to the BSFL and BSFP, was identified. The mites repeatedly bit and fed on the BSF bodily fluids, causing distress. The implications of mite infestation on colony health and viability are discussed, emphasising the need to maintain colony hygiene. Lastly, the apparent metabolisable energy (AME) and standardised ileal digestibility coefficients (SIDC) of amino acids (AA) of full-fat BSFL and BSFP meals for broiler chickens were determined. The AME and SIDC of BSFL and BSFP were higher than those reported for SBM, the commonly used protein meal in poultry diets. The findings demonstrated that BSFL and BSFP meals are better sources of energy and digestible AA, and are potential substitutes for SBM. Although the principles behind BSF bioconversion technology may seem straightforward, effective implementation requires deeper understanding of its complex stages. The present thesis provided a thorough overview of BSF technology, including rearing methods, optimising pupation conditions, the identification of a novel ectoparasite affecting BSF colonies, and the potential use of BSFL and BSFP into broiler chicken diets. By addressing these key aspects, the research contributes valuable insights for optimising BSF production and utilisation, particularly for small and medium-scale operations.
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    A comparative analysis of men's reluctance to seek health care : performing masculinity and deflecting blame : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Psychology at Massey University
    (Massey University, 2005) Fardell, Kate
    Men have higher rates of premature mortality than women and may arguably have higher of rates of morbidity. An explanation frequently offered to account for these gendered health differences is that men are reluctant to seek health care. This research, within a social constructionist framework, explores the discursive construction of men's reluctance to seek help by investigating through a comparative analysis the ways in which two small groups of men from different socio-economic locations make sense of the reluctance to seek help notion, as well as the implications of this discursive and social positioning for the enactment of their lives. Individual unstructured interviews with nine, mid-aged New Zealand men were analysed using Foucauldian Discourse Analysis. Two dominant discourses were identified in the men's accounts. A discourse of masculinity, which constructs reluctance to seek health care as a form of idealised masculinity, was draw upon by both working-class and professional men. In a contradictory account, working class men also drew on an impediment discourse, which constructs reluctance to seek help as a product of restrictive contextual factors that limit the health practices that men can undertake. Utilisation of the masculinity discourse enabled both groups of men to present themselves as masculine men and perform gender as socially prescribed. The impediment discourse also allowed working-class men to present themselves as victims of circumstance and deflect blame for their unwillingness to seek help from themselves to socio-structural restraints. Presenting themselves as masculine men and victims of circumstance was problematic for the men, as each of these positions was fraught with ambivalence. Their accounts reflect a series of unresolved tensions and dilemmas as they worked through the conflicts between the preservation of their social identity, acknowledging the need to seek help, and deflecting blame. They render overt the interplay between gender, power, and social class. These men's accounts are consistent with previous research that indicates that men are reluctant to seek help, but ascribe this to social expectations and socio-structural constraints. rather than individual choice. Reluctance to seek health care is thus reframed as a social issue.
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    Men, masculine identities, and healthcare utilisation : a thesis presented in partial fulfilment of the requirements for the degree of Master of Science in Psychology at Massey University
    (Massey University, 2006) Noone, John Hamilton
    Seeking medical help early in a disease process is critical for recovery, yet empirical evidence indicates that men do not utilise general practitioner services as often as women. In explaining these findings, the focus has now shifted away from the biological differences between men and women to examine popular beliefs about masculine identities and their influence on help seeking behaviour. This paper incorporates a critical analysis of Connell's (1995) theory of hegemonic masculinity to examine how men's relative under-utilisation of medical services, as negative health behaviour, can be influenced by the social construction of masculine identities. Interviews discussing the help seeking attitudes and behaviours of seven older rural men used a short movie clip and hypothetical scenarios as stimulants to discussion. The transcribed data was analysed using discursive analysis techniques, which resulted in the identification of three interpretative repertoires labelled: 'The Medical', 'The Natural Body', and 'Health Behaviours'. Many men faced a dilemma between identifying as a regular health care user, a morally virtuous position for all individuals, and identifying as an infrequent user of health care services, a virtuous position for men. They solved this dilemma by using the health behaviours repertoire to position women as the frequent and trivial users of health care whilst using the medical repertoire to position themselves as the legitimate users of health care. Furthermore, a number of respondents used the medical and natural body repertoires to construct a powerful masculine identity in relation to men that do not seek help and in relation to doctors. By using the three repertoires in this way these men could maintain a masculine identity whilst identifying as a regular and virtuous user of healthcare services. These results highlight the existence and complexity of multiple masculine identities and, in doing so, challenge theories that consistently polarise masculinity and help seeking health behaviours. These results therefore support hegemonic masculinity as a theory for examining the construction and maintenance of gendered identities.