Massey Research Online
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Validation of prediction equations to estimate the nutritive value of broiler chicken diets based on their chemical composition
(Elsevier BV, Netherlands, 2025-02-18) Thiruchchenthuran S; Zaefarian F; Abdollahi MR; Wester TJ; Morel PCH
An experiment was conducted to validate the accuracy of previously published prediction equations developed to estimate the coefficient of apparent ileal digestibility (CAID) and ileal digestible content (IDC) of nitrogen (N), crude fat, starch, calcium (Ca), phosphorus (P), energy, and dry matter (DM) in broilers using the chemical composition of diets. Twenty new diets were formulated to have a wide range of chemical characteristics relevant to commercial diets. The CAID of N, crude fat, starch, Ca, P, energy, and DM of the diets were determined in broiler growers fed ad libitum from 15 to 22 days post-hatch. The chemical composition and in vivo digestibility values were used to validate the prediction equations developed from a previous study. Comparison between the determined values and predicted values was used to assess the accuracy of prediction equations using the coefficient of determination (R2), root mean square error of prediction, concordance correlation coefficient (CCC), and mean bias (MB). The most accurate prediction was achieved in terms of R2 and CCC for CAID of energy and DM (R2 = 0.57 and 0.66, CCC = 0.45 and 0.47, respectively) as well as for IDC of N, starch, energy, and DM (R2 = 0.90, 1.00, 0.65, and 0.66, CCC = 0.48, 0.97, 0.51, and 0.47, respectively). The R2 and CCC values obtained for CAID of N, crude fat, starch, Ca, and P and IDC of Ca and P were not consistent with the expectation of predictive performance. The R2 for IDC of crude fat was high (0.94), however, CCC was moderate (0.43). The determined MB values showed that some equations underpredicted (CAID and IDC of N, crude fat, starch, energy, and DM) and some overpredicted (CAID of Ca and P and IDC of P) the observed values of in vivo study. In conclusion, the equations obtained for CAID of energy and DM as well as IDC of N, starch, energy, and DM could be considered the best fit according to R2 and CCC. Moreover, this study highlights the importance of validation with external data before applying each prediction equation to practical situations.
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Sensory Profile of Kombucha Brewed with New Zealand Ingredients by Focus Group and Word Clouds
(MDPI (Basel, Switzerland), 2021-06-23) Alderson H; Liu C; Mehta A; Gala HS; Mazive NR; Chen Y; Zhang Y; Wang S; Serventi L; Viejo CG; Fuentes S
Kombucha is a yeast and bacterially fermented tea that is often described as having an acetic, fruity and sour flavour. There is a particular lack of sensory research around the use of Kombucha with additional ingredients such as those from the pepper family, or with hops. The goal of this project was to obtain a sensory profile of Kombucha beverages with a range of different ingredients, particularly of a novel Kombucha made with only Kawakawa (Piper excelsum) leaves. Other samples included hops and black pepper. Instrumental data were collected for all the Kombucha samples, and a sensory focus group of eight semi-trained panellists were set up to create a sensory profile of four products. Commercially available Kombucha, along with reference training samples were used to train the panel. Kawakawa Kombucha was found to be the sourest of the four samples and was described as having the bitterest aftertaste. The instrumental results showed that the Kawakawa Kombucha had the highest titratable acidity (1.55 vs. 1.21–1.42 mL) as well as the highest alcohol percentage (0.40 vs. 0.15–0.30%). The hops sample had the highest pH (3.72 vs. 3.49–3.54), with the lowest titratable acidity (1.21), and, from a basic poll, was the most liked of the samples. Each Kombucha had its own unique set of sensory descriptors with particular emphasis on the Kawakawa product, having unique mouthfeel descriptors as a result of some of the compounds found in Kawakawa. This research has led to a few areas that could be further studied, such as the characteristics of the Piperaceae family under fermentation and the different effects or the foaminess of the Kawakawa Kombucha, which is not fully explained.
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Reconstruction of gene innovation associated with major evolutionary transitions in the kingdom Fungi
(BioMed Central Ltd, 2022-12) Wu B; Hao W; Cox MP
BACKGROUND: Fungi exhibit astonishing diversity with multiple major phenotypic transitions over the kingdom's evolutionary history. As part of this process, fungi developed hyphae, adapted to land environments (terrestrialization), and innovated their sexual structures. These changes also helped fungi establish ecological relationships with other organisms (animals and plants), but the genomic basis of these changes remains largely unknown.
RESULTS: By systematically analyzing 304 genomes from all major fungal groups, together with a broad range of eukaryotic outgroups, we have identified 188 novel orthogroups associated with major changes during the evolution of fungi. Functional annotations suggest that many of these orthogroups were involved in the formation of key trait innovations in extant fungi and are functionally connected. These innovations include components for cell wall formation, functioning of the spindle pole body, polarisome formation, hyphal growth, and mating group signaling. Innovation of mitochondria-localized proteins occurred widely during fungal transitions, indicating their previously unrecognized importance. We also find that prokaryote-derived horizontal gene transfer provided a small source of evolutionary novelty with such genes involved in key metabolic pathways.
CONCLUSIONS: The overall picture is one of a relatively small number of novel genes appearing at major evolutionary transitions in the phylogeny of fungi, with most arising de novo and horizontal gene transfer providing only a small additional source of evolutionary novelty. Our findings contribute to an increasingly detailed portrait of the gene families that define fungal phyla and underpin core features of extant fungi.
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Identification of novel biomarkers for the prediction of subclinical coronary artery atherosclerosis in patients with rheumatoid arthritis: an exploratory analysis
(BioMed Central Ltd, 2023-12) Bathon JM; Centola M; Liu X; Jin Z; Ji W; Knowlton NS; Ferraz-Amaro I; Fu Q; Giles JT; Wasko MC; Stein CM; Van Eyk JE
Background: Cardiovascular (CV) risk estimation calculators for the general population underperform in patients with rheumatoid arthritis (RA). The purpose of this study was to identify relevant protein biomarkers that could be added to traditional CV risk calculators to improve the capacity of coronary artery calcification (CAC) prediction in individuals with RA. In a second step, we quantify the improvement of this prediction of CAC when these circulating biomarkers are added to standard risk scores.
Methods: A panel of 141 serum and plasma proteins, which represent a broad base of both CV and RA biology, were evaluated and prioritized as candidate biomarkers. Of these, 39 proteins were selected and measured by commercial ELISA or quantitative mass spectroscopy in 561 individuals with RA in whom a measure of CAC and frozen sera were available. The patients were randomly split 50:50 into a training/validation cohort. Discrimination (using area under the receiver operator characteristic curves) and re-classification (through net reclassification improvement and integrated discrimination improvement calculation) analyses were performed first in the training cohort and replicated in the validation cohort, to estimate the increase in prediction accuracy for CAC using the ACA/AHA (American College of Cardiology and the American Heart Association) score with, compared to without, addition of these circulating biomarkers.
Results: The model containing ACC/AHA score plus cytokines (osteopontin, cartilage glycoprotein-39, cystatin C, and chemokine (C–C motif) ligand 18) and plus quantitative mass spectroscopy biomarkers (serpin D1, paraoxonase, and clusterin) had a statistically significant positive net reclassifications index and integrated discrimination improvement for the prediction of CAC, using ACC/AHA score without any biomarkers as the reference category. These results were confirmed in the validation cohort.
Conclusion: In this exploratory analysis, the addition of several circulating CV and RA biomarkers to a standard CV risk calculator yielded significant improvements in discrimination and reclassification for the presence of CAC in individuals with RA.
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Effects of intranasal maropitant on clinical signs of naturally acquired upper respiratory disease in shelter cats
(SAGE Publications on behalf of the nternational Cat Care Veterinary Society and Feline Veterinary Medical Association, 2025-02-26) Parncutt J; Johnson LR; Subharat S; Oke B; Hill KE
OBJECTIVES: The aim of this study was to test the hypothesis that intranasally administered maropitant citrate would reduce the severity of clinical signs of feline upper respiratory disease (FURD) in shelter cats with naturally acquired disease.
METHODS: Shelter cats with clinical signs of FURD were randomly assigned to receive either intranasal maropitant diluted in saline (maropitant citrate 10 mg/ml q12h, diluted 1:10 with sterile 0.9% saline) or intranasal 0.9% saline q12h for 7 days. Clinical disease severity was measured at entry into the study and again after completion of 7 days of treatment using a visual analogue scale to assess four separate clinical signs: conjunctivitis, blepharospasm, ocular discharge and nasal discharge. Total disease severity was also calculated. Cats received other medications for FURD as per standard shelter protocols, and all investigators were masked to group assignments. A Mann-Whitney U-test was performed to compare the clinical improvement score (CIS) between the treatment and control groups.
RESULTS: There were 34 cats in the maropitant treatment group; 27 cats served as placebo controls. Groups did not differ in age, sex distribution, nature of disease, administration of other medications for FURD or baseline clinical disease severity. There was no significant difference in CIS between the maropitant treatment and control groups for conjunctivitis, blepharospasm, ocular discharge, nasal discharge or total disease severity after 7 days.
CONCLUSIONS AND RELEVANCE: This study found no significant difference in outcomes for cats with FURD when treated with intranasal maropitant compared with treatment with intranasal saline. Further investigations would be required before intranasal maropitant could be recommended as the standard of care for FURD.