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    Individuals' perspectives of causes and influences on their diagnosed anxiety disorders : a thesis presented in partial fulfilment of the requirements for the degree of Master of Arts in Psychology at Massey University, Albany, New Zealand
    (Massey University, 2013) Birrell, Lyn
    Anxiety disorders are the most common type of mental disorder in New Zealand, as they are in the Western world. However, little research has been done on how persons with anxiety disorder conceptualize their respective diagnoses. This small community based, qualitative study interviewed seven individuals diagnosed with anxiety disorders and tried to capture the content and complexity of their disorder. Volunteer participants responded to a flyer placed at an anxiety disorders clinic, located in Auckland, New Zealand. Participants included one male and six females, aged from mid 20 to early 40s. Criteria for participation included being diagnosed with an anxiety disorder by a health professional. Participants generally spoke in terms of their problems in living, as well as the development and course of their disorder. All participants reported that (1) their disorder was chronic and pervasive; (2) their condition was debilitating at times; (3) their condition was complicated by depression; and (4) dysfunction or disruption was present in their early family life. Most participants talked about the early onset of disorder. Recognizing and acting on the need for help was problematic for most participants. Thematic analysis was undertaken to best account for the data, which unfolded as a coherent, consistent and holistic narrative. Three common broad developmental themes were identified: traumatic early life, troubled school life and problems with living. Two broad themes were created to capture participants’ thoughts and feelings following diagnosis: rationalisation and post-rationalisation. Discussion specifically suggested the need for further research into the aetiology of anxiety disorders, including the role of maternal controlling behaviour and early onset of the disorder. Further research is also needed to understand and facilitate the help-seeking process for persons suffering from anxiety disorders. A need was identified for the accurate detection of anxiety disorders, particularly when masked by a presentation of depression or other symptoms. Findings suggest that a developmental/ social/contextual model may be most useful in conceptualizing and guiding prevention, intervention and treatment plans. In addition, the impact and meaning of the diagnostic event on people with anxiety disorders requires examination to fully understand all the dynamics and ramifications. Implications from this study include the need for initiatives to aid early recognition and generally to educate people about the nature of anxiety disorders, including the fact that they are common, serious and treatable.
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    In vitro and in vivo studies on treatment and prevention of bovine mastitis : a thesis presented in partial fulfilment of the requirements for the degree of Philosophy Doctor in Veterinary Science at Massey University, Palmerston North, New Zealand
    (Massey University, 2011) Petrovski, Kiro R.
    Mastitis prevalence on dairy farms depends on the number of infected cows and the duration of each intramammary infection. Strategies aiming to influence these factors are the subject of research presented in this thesis. Decreasing the duration of infection can be achieved by successfully treating infected quarters. Treatment of mastitis can occur during lactation or in the dry period. Treatment success is influenced by the concentration of antimicrobial achieved at the site of infection and the length of time it is present. The concentration of antimicrobial should exceed the relevant minimal inhibitory concentration. The susceptibility of mastitis-causing organisms varies among geographical areas and over time. New Zealand’s susceptibility data demonstrated a high susceptibility to penicillin. A formulation containing this antimicrobial was administered to healthy lactating cows milked once or twice daily. The concentrations of penicillin in milk were above the minimal inhibitory concentrations for the entire inter-dosing interval. Doubling the number of treatments or milking once-a-day resulted in a significantly increased time above the minimal inhibitory concentrations. The number of new infections is greatest during the early dry period in mature cows and in the pre-calving period in both heifers and mature cows. Pre-partum administration of delayed release antimicrobial formulations in heifers decreased the incidence of clinical mastitis and resulted in better reproductive performance, but not in increased milk production, when compared to control heifers. More effective prevention of new infections within the dry period was achieved by administering a novel teat sealant to mature cows when compared to a commercial teat sealant and untreated controls. Strategies for shortening the duration of intramammary infections and decreasing the number of affected cows at the start of lactation investigated in this thesis should reduce the prevalence of mastitis on dairy farms in New Zealand.
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    The aetiology of wobbly possum disease: Reproduction of the disease with purified nidovirus.
    (2016-04) Giles J; Perrott M; Roe W; Dunowska M
    The objective of this study was to investigate a role of a recently discovered marsupial nidovirus in the development of a neurological disease, termed wobbly possum disease (WPD), in the Australian brushtail possum (Trichosurus vulpecula). Four possums received 1 mL of a standard inoculum that had been prepared from tissues of WPD-affected possums, 4 possums received 1.8 mL (1 × 10(6) TCID50) of a cell lysate from inoculated cultures, and 4 possums received 1 mL (× 10(7) TCID50) of a purified WPD isolate. All but one possum that received infectious inocula developed neurological disease and histopathological lesions characteristic for WPD. High levels of viral RNA were detected in livers from all possums that received infectious inocula, but not from control possums. Altogether, our data provide strong experimental evidence for the causative involvement of WPD virus in development of a neurological disease in infected animals.