908 results for Journal article, Lincoln University Research Archive

  • An association between lifespan and variation in IGF1R in sheep.

    Byun, Seung O.; Forrest, R. H.; Frampton, C. M.; Zhou, Huitong; Hickford, Jonathan G. H.

    Journal article
    Lincoln University

    Longevity in livestock is a valuable trait. When productive animals live longer fewer replacement animals need to be raised. However, selection for longevity is not commonly the focus of breeding programs as direct selection for long-lived breeding stock is virtually impossible until late in the animal's reproductive life. Additionally the underlying genetic factors or genes associated with longevity are either not known, or not well understood. In humans, there is evidence that insulin-like growth factor 1 receptor (IGF1R) is involved in longevity. Polymorphism in the IGF1R gene (IGF1R) has been associated with longevity in a number of species. Recently, 3 alleles of ovine IGF1R were identified, but no analysis of the effect of IGF1R variation on sheep longevity has been reported. In this study, associations between ovine IGF1R variation, longevity and fertility were investigated. PCR-single strand conformational polymorphism (PCR-SSCP) was used to type IGF1R variation in 1716 New Zealand sheep belonging to 6 breeds and 36 flocks. Ovine IGF1R C was associated with age when adjusting for flock (present 5.5 ± 0.2 yr, absent 5.0 ± 0.1 yr, P = 0.02). A general linear mixed effects model suggested an association (P = 0.06) between age and genotype, when correcting for flock. Pairwise comparison (least significant difference) of specific genotypes revealed the difference to be between AA (5.0 ± 0.1 yr) and AC (5.6 ± 0.2 yr, P = 0.02). A weak negative Pearson correlation between fertility and longevity traits was observed (r = -0.25, P < 0.01). The finding of an association between variation in IGF1R and lifespan in sheep may be useful in prolonging the lifespan of sheep.

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  • Is kanuka and manuka establishment in grassland constrained by mycorrhizal abundance?

    Davis, M.; Dickie, I. A.; Paul, T.; Carswell, F.

    Journal article
    Lincoln University

    Two indigenous small tree and shrub species, kanuka (Kunzea ericoides) and manuka (Leptospermum scoparium), have potential as reforestation species in New Zealand as they are forest pioneer species that can invade grassland naturally from present seed sources. The aim of this study was to determine if establishment of kanuka and manuka from seed in grassland distant from stands of these species might be constrained by lack of appropriate mycorrhizal fungi. Both species were grown in an unsterilised grassland soil from a low productivity montane site assumed to be devoid of appropriate mycorrhizal fungi and inoculated with sterilised or unsterilised O-horizon or mineral soil from beneath three kanuka and three manuka communities expected to contain such fungi. Inoculation with unsterilised O-horizon soil improved kanuka biomass by 36-92%, depending on the source of the inoculant. Inoculation did not improve manuka biomass. No ectomycorrhizal infection was observed on either kanuka or manuka in samples examined under binocular microscope. The biomass response by kanuka to inoculation may be due to introduction of more effective arbuscular mycorrhizal fungi from kanuka communities or possibly to the introduction of soil microorganisms. Testing of inoculation under field conditions will be essential to determine whether establishment of either species in grassland soil by seeding is seriously constrained by lack of appropriate mycorrhizal fungi or soil microorganisms.

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  • Modeling dynamic processes in smallholder dairy value chains in Nicaragua: a system dynamics approach

    Lie, H.; Rich, Karl

    Journal article
    Lincoln University

    In Nicaragua, the production of dairy and beef is the most important source of household income for many smallholder producers. However, erratic volumes and quality of milk limit the participation of small- and medium-scale cattle farmers into higher-value dairy value chains. This research uses a system dynamics (SD) approach to analyze the Matiguás dairy value chain in Nicaragua. The paper presents the conceptual framework of the model and highlights the dynamic processes in the value chain, with a focus on improving feeding systems to achieve higher milk productivity and increased income for producers. The model was developed using a participatory group model building (GMB) technique to jointly conceptualize and validate the model with stakeholders.

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  • Potential for forage diet manipulation in New Zealand pasture ecosystems to mitigate ruminant urine derived N₂O emissions: a review

    Gardiner, Camilla; Clough, Timothy J.; Cameron, Keith C.; Di, Hong J.; Edwards, Grant; de Klein, C. A. M.

    Journal article
    Lincoln University

    © 2016 The Royal Society of New Zealand. Nitrous oxide (N₂O) emissions from agricultural soils account for more than 10% of New Zealand’s greenhouse gas emissions. Livestock urine deposition drives N₂O losses from these soils. It has been speculated that non-urea nitrogen compounds (UNCs) in ruminant urine could reduce or inhibit urine patch N₂O emissions. However, we hypothesise that UNCs will have no effect on N₂O emissions due to their potentially rapid degradation by plants and soil microbes. Our review suggests that plant secondary metabolites (PSMs) are more likely to perform a role in reducing N₂O emissions since many PSMs have known antimicrobial properties. Aucubin, found in Plantago, and isothiocyanates, found in Brassica, have been shown to inhibit a key step in N₂O production. Future studies should explore this promising research gap by evaluating forages for potential inhibitory PSMs, assessing whether PSMs are excreted in urine after consumption, and determine whether excretal PSM concentrations are sufficient to reduce N₂O emissions.

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  • Survey of barley grain physical processing methods in Holstein dairy cow's ration

    Nejat, M. A.; Basaki, T; Safa, M.

    Journal article
    Lincoln University

    Barley is one of the most commonly used food grains in the diet of dairy and beef cattle. Since barley endosperm is enclosed by a sheath highly resistant to microbe degradation in Rumen, it is necessary to process dry barley grain for optimal use by dairy and beef cattle. In order to compare different methods of barley grain’s physical processing in the diet of dairy cattle and its effect on milk production, 9 Holstein cattle (in the first, second and third birth) that were at a distance of 10 ± 65 days after delivery, were selected . This experiment was performed was in a randomized complete block design with three replications (parity), four treatments (processing method) and three cattle per block. Barely grains were put in diets numbered from 1 to four, respectively through the following ways:(1) Hammer mill (with a sieve 1 mm), (2) dry roll by Index processing 73%, (3) Fusion (a mixture of first way and second way ) (4) rolling along with steam by processing index 65% of processing percent. The data included amount of milk, percent of fat and dry matter use for each of the three milking. Average milk production of cattle that were fed by diets 1, 2, 3 and 4 were respectively 33.60c, 34.23b, and 34.38b and 34.60a kg per day. Also the averages of fat percent were equal to 3.02a, 2.70c, and 2.73c and 2.84b. In both groups, the mean difference was significant at one percent level. According to the findings and production purpose (the increase of milk production) rolling machine under steam can be proposed, however, considering high cost of the device, it can be justified for large units. For small farms, dry roll with less processing index is recommended.

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  • Leading different dimensions of organization performance through human resource management practices

    Mansouri, N.; Goher, Khaled

    Journal article
    Lincoln University

    The primary purpose of this research work is to find out how human resource management practices including training, staffing, performance appraisal, participation, and reward system can affect the performance of Malaysian Information and Communication Technology (ICT) companies. Company’s performance is identified in this work in terms of innovation, learning and growth, and internal process. The results of analysis of 223 gathered data showed that human resource management practices have significant and positive impact on innovation, learning and growth, and internal process. In addition, this study showed that performance components can affect each other significantly and positively. In this research work, the data is collected through questionnaire and analyzed by Statistical Package for the Social Sciences (SPSS) software. Moreover, the respondents of this research work are the employees of small and medium size ICT companies located in Cyberjaya, Malaysia.

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  • Hierarchical neighbor effects on mycorrhizal community structure and function

    Moeller, H. V.; Dickie, Ian; Peltzer, D. A.; Fukami, T.

    Journal article
    Lincoln University

    © 2016 The Authors. Ecology and Evolution published by John Wiley & Sons Ltd.Theory predicts that neighboring communities can shape one another's composition and function, for example, through the exchange of member species. However, empirical tests of the directionality and strength of these effects are rare. We determined the effects of neighboring communities on one another through experimental manipulation of a plant-fungal model system. We first established distinct ectomycorrhizal fungal communities on Douglas-fir seedlings that were initially grown in three soil environments. We then transplanted seedlings and mycorrhizal communities in a fully factorial experiment designed to quantify the direction and strength of neighbor effects by focusing on changes in fungal community species composition and implications for seedling growth (a proxy for community function). We found that neighbor effects on the composition and function of adjacent communities follow a dominance hierarchy. Specifically, mycorrhizal communities established from soils collected in Douglas-fir plantations were both the least sensitive to neighbor effects, and exerted the strongest influence on their neighbors by driving convergence in neighbor community composition and increasing neighbor seedling vigor. These results demonstrate that asymmetric neighbor effects mediated by ecological history can determine both community composition and function.

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  • A systems approach for determining gene expression from experimental observation of compound presence and absence

    Clark, Sangaalofa; Verwoerd, Wynand S.

    Journal article
    Lincoln University

    Different genes are expressed in different tissues, depending on functional objectives and selection pressures. Based on complete knowledge of the structure of the metabolic network and all the reactions taking place in the cell, elementary modes (EMs) and minimal cut sets (MCSs) can relate compounds observed in a tissue, to the genes being expressed by respectively providing the full set of non-decomposable routes of reactions and compounds that lead to the synthesis of external products, and the full set of possible target genes for blocking the synthesis of external products. So, for a particular tissue, only the EMs containing the reactions that are related to the genes being expressed in those tissues, are active for the production of the corresponding compounds. This concept is used to develop an algorithm for determining a matrix of reactions (which can be related to corresponding genes) taking place in a tissue, using experimental observations of compounds in a tissue. The program is applied to the Arabidopsis flower and identified 20 core reactions occurring in all the viable EMs. They originate from the trans-cinnamate compound and lead to the formation of kaempferol and quercetin compounds and their derivatives, as well as anthocyanin compounds. Analyses of the patterns in the matrix identify reaction sets related to certain functions such as the formation of derivatives of the two anthocyanin compounds present, as well as the reactions leading from the network’s external substrate erythrose-4P to L-Phenyla- lanine, cinnamyl-alc to trans-cinnamate and so on. The program can be used to successfully determine genes taking place in a tissue, and the patterns in the resulting matrix can be analysed to determine gene sets and the state of the tissue.

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  • Creating a Chinatown – Considerations for Christchurch

    Duyndam, Grace

    Journal article
    Lincoln University

    With the recent innovation and development within Christchurch following the earthquakes there have been suggestions of developing an ethnic precinct or 'Chinatown' within the city. This article explores the possibility of this and its potential benefits.

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  • Meat industry woes: can we do better?

    Woodford, Keith B.

    Journal article
    Lincoln University

    There are lots of unhappy sheep farmers at the moment. A season that gave promise of providing better prices than last year has spiralled down into the gloomy depths. Most farmers seem ready to blame the meat companies but many of the problems arise elsewhere. The current exchange rates are hugely problematic for exporting industries, but even that is not the total answer. Farmers too have got to take some of the responsibility for the position the industry is in. And farmers are going to have to do something about it themselves if they want things to improve. Of course there is nothing that individual farmers can do about exchange rates. That is up to Government. So somehow, farmers have got to make the best of it until the wheel turns in their favour. Or is there something that farmers can do? What is actually wrong with the meat industry that can be improved?

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  • The A2 milk debate: Searching for the evidence

    Woodford, Keith B.

    Journal article
    Lincoln University

    The debate about A2 milk has been in the public arena for at least five years. There have been lots of claims and counter claims about whether ‘ordinary milk’, which is a mixture of A1 and A2 milk, is linked to a range of disease conditions, and whether selecting for cows that produce only A2 milk can avoid these problems. Despite the claims and counter claims, the substance of the arguments has not been widely aired in public. Instead, most people have only heard the assertions. Therefore it has been a case of making a judgement as to which of the two competing sides has most credibility. In early August 2004 the New Zealand Food Safety Authority (NZFSA) released the ‘Swinburn Report’ (Swinburn 2004). The NZFSA had contracted Professor Boyd Swinburn back in March 2003 to review the scientific evidence for and against the A1/A2 hypothesis. Depending on which media report people were exposed to, it would have been reasonable to accept either that the Swinburn Review had found that there was no difference between A1 and A2 milk, or that there were indeed significant concerns about the health implications of A1 milk. And so the issues remain as muddy as ever. The purpose of this paper is to present the evidence for and against. In that way dairy farmers and their consultants can make their own judgements as to whether or not this is an issue that they need to be concerned about.

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  • Do runoffs pay?

    Woodford, Keith B.

    Journal article
    Lincoln University

    One of the ongoing debates amongst farmers and consultants is whether runoffs pay. Last summer Brendan Richards, as part of his Master of Applied Science studies at Lincoln University, decided to get some numbers on what has been happening with runoffs in Canterbury. Brendan identified six case study farmers who had diverse farming systems on a range of different land types. This report summerises Brendan Richards findings and provides a set of benchmarks against which other farmers may like to compare their own operations.

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  • Belowground legacies of Pinus contorta invasion and removal result in multiple mechanisms of invasional meltdown

    Dickie, Ian; St John, M. G.; Yeates, G. W.; Morse, C. W.; Bonner, K. I.; Orwin, K. H.; Peltzer, D. A.

    Journal article
    Lincoln University

    Plant invasions can change soil biota and nutrients in ways that drive subsequent plant communities, particularly when co-invading with belowground mutualists such as ectomycorrhizal fungi. These effects can persist following removal of the invasive plant and, combined with effects of removal per se, influence subsequent plant communities and ecosystem functioning. We used field observations and a soil bioassay with multiple plant species to determine the belowground effects and post-removal legacy caused by invasion of the non-native tree Pinus contorta into a native plant community. Pinus facilitated ectomycorrhizal infection of the co-occurring invasive tree, Pseudotsuga menziesii, but not conspecific Pinus (which always had ectomycorrhizas) nor the native pioneer Kunzea ericoides (which never had ectomycorrhizas). Pinus also caused a major shift in soil nutrient cycling as indicated by increased bacterial dominance, NO₃⁻N (17-fold increase) and available phosphorus (3.2-fold increase) in soils, which in turn promoted increased growth of graminoids. These results parallel field observations, where Pinus removal is associated with invasion by non-native grasses and herbs, and suggest that legacies of Pinus on soil nutrient cycling thus indirectly promote invasion of other non-native plant species. Our findings demonstrate that multi-trophic below-ground legacies are an important but hitherto largely unconsidered factor in plant community reassembly following invasive plant removal.

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  • South Island high country land reform 1992-2015

    Brower, Ann L.

    Journal article
    Lincoln University

    A summary of high country tenure review outcomes since 1992. New Zealanders have long treasured their land, with poets (Bracken, 1893) and prime ministers calling it ‘God’s Own Country’, or Godzone for short. On his visit to New Zealand in 1897 Mark Twain wrote: ‘The people are Scotch. They stopped here on their way from home to heaven – thinking they had arrived’ (Twain, 1897).

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  • Knowing sea turtles: local communities informing conservation in Koh Rong Archipelago, Cambodia

    Diamond, Juliane; Blanco, V.; Duncan, Ronlyn

    Journal article
    Lincoln University

    Three globally threatened species of sea turtle have been recorded in the waters around the Koh Rong Archipelago off Cambodia’s southwest coast: the green turtle Chelonia mydas, the hawksbill Eretmochelys imbricata and the leatherback Dermochelys coriacea. To learn how human communities around the Koh Rong Archipelago interact with these turtle species, we investigated their perceptions and use of sea turtles. Our study used qualitative social science research methods and identified four frames of reference for the sea turtle: turtles as victims, turtles as occasional food, turtles as spiritual beings, and turtles as a promise for the future. These frames of reference were expressed in all villages and among most demographic groups. Our study also identified several perceived threats to sea turtle survival around the Koh Rong Archipelago. The most frequently cited threats were trawling boats, nets, Vietnamese fishermen, hooks, illegal fishing and overfishing. Understanding how local people interpret and interact with sea turtles and perceive threats to their survival provides important insights for nature conservation and education programmes, which our study aims to inform.

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  • Equity in sharing the potential benefits of REDD+ in Nepal

    Sherpa, D. T.; Brower, Ann L.

    Journal article
    Lincoln University

    Reducing Emissions from Deforestation and Forest Degradation (REDD+) is an incentive based climate change mitigation measure that focuses on reducing carbon emissions by rewarding communities’ efforts in the conservation, sustainable management of forests and enhancement of carbon stocks. Assuming REDD+ revenues are generated, there is a question about how the benefits should be distributed. This paper uses the 3Es (Effectiveness, Efficiency and Equity) criteria in sharing the benefits of REDD+ to examine a case study in one of Nepal’s REDD+ pilot projects implemented in community forests. While concerns about equity in REDD+ are getting attention worldwide, the literature is not clear on which principle of 3Es should be given priority to achieve overall effectiveness in reducing the carbon emissions. Our research finds that equity should be prioritised to achieve efficiency and effectiveness of REDD+. Further, we find distributive equity to be the most important. Distributive equity is understood in three different ways in Nepal: rights, needs, and performance. But there is a debate on which equity should be given priority. The issues of needs vs. performance in determining what is equitable should be solved by the formulation of guidelines for how benefits should be shared at two levels in Nepal. First, the vertical distribution of benefits should be based on the ownership of carbon benefits and performance criteria. Second, at the community level, the community itself should determine the form of horizontal benefit-distribution, based on its definition of needs.

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  • Whither the Crown’s interest in South Island high country land reform?

    Brower, Ann L.

    Journal article
    Lincoln University

    The South Island high country has long been the subject of debate over resource use and ecological protection. Since early 2006, the ownership and relative value of property rights in high country pastoral leases have become controversial. This article reviews recent research (chiefly Brower (2006) and Brower, Monks and Meguire (in review)) on the law, politics and economics of land reform in the high country.

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  • Land rort, Pakeha style

    Brower, Ann L.

    Journal article
    Lincoln University

    The article presents an overview of the updated tenure review of the South Island high country in New Zealand. It discusses the Lockean view of land ownership which vindicated the government paying public money while giving away public properties. It also talks about the tactics pursued by the government leaders and officials in giving out valuable national assets.

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  • Minimal cut sets and the use of failure modes in metabolic networks

    Clark, Sangaalofa; Verwoerd, Wynand S.

    Journal article
    Lincoln University

    A minimal cut set is a minimal set of reactions whose inactivation would guarantee a failure in a certain network function or functions. Minimal cut sets (MCSs) were initially developed from the metabolic pathway analysis method (MPA) of elementary modes (EMs); they provide a way of identifying target genes for eliminating a certain objective function from a holistic perspective that takes into account the structure of the whole metabolic network. The concept of MCSs is fairly new and still being explored and developed; the initial concept has developed into a generalized form and its similarity to other network characterizations are discussed. MCSs can be used in conjunction with other constraints-based methods to get a better understanding of the capability of metabolic networks and the interrelationship between metabolites and enzymes/genes. The concept could play an important role in systems biology by contributing to fields such as metabolic and genetic engineering where it could assist in finding ways of producing industrially relevant compounds from renewable resources, not only for economical, but also for sustainability reasons.

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  • Accessibility and attractiveness - key features towards central city revitalisation - a case study of Christchurch, New Zealand

    Thull, Jean-Paul; Mersch, Marc

    Journal article
    Lincoln University

    Article published in the Journal of the Eastern Asia Society for Transportation Studies, Vol. 6 (2005), p. 4066-4081.

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