32 results on '"I. M. Nevison"'
Search Results
2. Investigation of the distribution of anticoagulant rodenticide residues in red fox (Vulpes vulpes) livers to ensure optimum sampling protocol
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Michael Taylor, Steve Campbell, Fabio Casali, Andrzej Posyniak, Marta Giergiel, Gill Hartley, I. M. Nevison, Anna Giela, and Elizabeth Ann Sharp
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Residue (complex analysis) ,Veterinary medicine ,medicine.drug_class ,Vulpes ,Anticoagulant ,Bromadiolone ,Biology ,Sub-sampling ,biology.organism_classification ,Red fox ,lcsh:TD1-1066 ,chemistry.chemical_compound ,Anticoagulant rodenticides ,chemistry ,Liver Lobe ,Liver ,Liquid chromatography–mass spectrometry ,medicine ,QD ,Rodenticide ,Lobular distribution ,lcsh:Environmental technology. Sanitary engineering ,Brodifacoum - Abstract
The lobular distribution of 9 different anticoagulant rodenticide (AR) residues in the liver of a sentinel predator/scavenger i.e. the red fox (Vulpes vulpes) was determined following multi-residue analysis using Ultra (High) Performance Liquid Chromatography tandem Mass Spectrometry (UHPLC-MS/MS). The aim of the study was to address concerns that if distribution of AR residues in the liver was significantly heterogeneous, analysis of random sub-samples or finite remnants of liver could result in false negatives or lead to incorrect toxicological diagnoses. Intact livers excised from animals shot as part of routine legal pest control activities in Scotland during 2018 and 2019 were sub-sectioned and the lobular concentration of AR residues was investigated. Analysis of individual lobes from 10 different fox livers revealed that AR residues initially detected in a randomly selected small portion of liver tissue were present throughout the liver. Also, in cases where AR residues were not found in the initial randomly selected portion, they were not found in the subsequent more detailed examination. The limit of quantitation was 3 μg kg‐1 and AR residue concentrations ranged from 3 to 885 μg kg−1. Statistical analysis of variance (ANOVA) was performed on the eight and six out of ten livers that tested positive for bromadiolone and brodifacoum, respectively. No statistical evidence was found of differences in mean residue levels of bromadiolone throughout the liver i.e. within and between liver lobes. However, brodifacoum showed a statistically significant difference (p < .001) in mean residue concentration between the lobes but there was no statistical evidence of mean differences within the lobes.
- Published
- 2020
3. Rhynchosporium leaf scald disease incidence: seed source and spatial pattern
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C. F. E. Topp, Neil D. Havis, Adam Butler, I. M. Nevison, Gareth Hughes, and S. J. P. Oxley
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biology ,Agronomy ,Crop yield ,Rhynchosporium ,Genetics ,Common spatial pattern ,Plant Science ,Field tests ,Horticulture ,biology.organism_classification ,Rhynchosporium commune ,Agronomy and Crop Science - Published
- 2019
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4. What type of loafing areas do housed dairy cattle prefer?
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Marie J. Haskell, I. M. Nevison, Fritha M. Langford, DJ Bell, David J. Roberts, and Bert J. Tolkamp
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Geography ,Animal science ,Food Animals ,Area type ,Preference test ,Social loafing ,Free access ,Animal Science and Zoology ,Scan sampling ,Dairy cattle - Abstract
Providing continuously-housed dairy cows with a loafing area may allow them space to express behaviours that are affected by the housing environment. The aim of this study was to investigate whether dairy cows had a preference for loafing area type and if loafing area type affected behaviour performed within it. Three groups of 12 and one group of 11 lactating cows (n=47) were housed in a cubicle shed with two nearby loafing areas 1) a concrete-floored roofed area and 2) a grassed paddock fenced to the same size as the concrete area. After 3d baseline period without access, cows were trained to access the loafing areas over 2 days. A 5d preference test followed, where cows had free access to the cubicle shed and both loafing areas from 08:45 until 12:45 and 15:30 to 18:30. Behaviour was observed via live observations (scan sampling) in the mornings and afternoons and activity sensors (IceTags) continuously recorded lying bouts 24 h/d until the end of the experiment. Results of the live observations showed that the cows were in the paddock area for more of the scans than the concrete area (P
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- 2021
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5. Aggressive behaviour at regrouping is a poor predictor of chronic aggression in stable social groups
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Mhairi Jack, Richard B. D’Eath, Sarah H. Ison, I. M. Nevison, Simon P. Turner, Suzanne Desire, Irene Camerlink, Rainer Roehe, and Marianne Farish
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education.field_of_study ,Aggression ,media_common.quotation_subject ,05 social sciences ,Population ,0402 animal and dairy science ,Stopping rule ,04 agricultural and veterinary sciences ,040201 dairy & animal science ,Developmental psychology ,Lesion ,Social group ,Food Animals ,medicine ,Trait ,0501 psychology and cognitive sciences ,Animal Science and Zoology ,050102 behavioral science & comparative psychology ,medicine.symptom ,Psychology ,Skin lesion ,education ,Welfare ,media_common ,Demography - Abstract
Commercial pigs globally are routinely mixed into new social groups. This results in regrouping aggression predominantly during the first 24 h which compromises welfare and productivity. Chronic aggression persists thereafter and is also undesirable. Management strategies are needed that reduce the costs of aggression in both of these contexts. Pigs vary greatly in aggressive behaviour and numbers of skin lesions. This study examined how regrouping behaviour affects immediate and long-term lesion counts with a specific focus on understanding the behaviour of pigs with few lesions in both social contexts. Aggressive behaviour from 1163 growing pigs was observed for 24 h post-regrouping and fresh lesions were counted 24 h and 3 weeks post-regrouping. Similarity between pigs was calculated using all behavioural traits recorded during the 24 h post-regrouping. Clusters of pigs were formed using furthest neighbour clustering with a stopping rule of 80% similarity. Five clusters of pigs representing 90% of the population (1047 pigs) were identified. For each regrouping aggressive behaviour trait and for fresh lesion counts 24 h post-regrouping the means differed significantly (P
- Published
- 2017
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6. Compositional mixed modeling of methane emissions and ruminal volatile fatty acids from individual cattle and multiple experiments1
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John Rooke, J. Palarea-Albaladejo, Richard J. Dewhurst, and I. M. Nevison
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0301 basic medicine ,chemistry.chemical_classification ,Mixed model ,animal structures ,genetic structures ,0402 animal and dairy science ,Forage ,04 agricultural and veterinary sciences ,General Medicine ,Beef cattle ,Valerate ,040201 dairy & animal science ,03 medical and health sciences ,Rumen ,030104 developmental biology ,Animal science ,chemistry ,Yield (chemistry) ,Environmental chemistry ,Genetics ,Propionate ,Animal Science and Zoology ,Compositional data ,Food Science - Abstract
The aim of the study was to investigate the association of methane (CH) yields (g/kg DMI) with rumen VFA molar proportions and animal and diet-related covariates from individual animals and multiple experiments. The dataset available consisted of 284 measurements of CH yields for beef cattle from 6 experiments measured in indirect respiration chambers. A compositional modeling approach was employed where VFA measurements were considered as a whole, instead of in isolation, emphasizing their multivariate relative scale. The analysis revealed expected close groupings of acetate and butyrate; propionate and valerate; iso-butyrate and iso-valerate. Linear mixed models were then fitted to examine relationships between CH yield and VFA, represented by meaningful log-contrasts of components called compositional balances, while accounting for other animal and diet-related covariates and random variability between experiments. A compositional balance representing (acetate × butyrate)/propionate best explained the contribution of VFA to variation in CH yield. The covariates DMI, forage:concentrate proportion (expressed as a categorical variable diet type: high concentrate, mixed forage:concentrate or high forage), and diet ME were also statistically significant. These results provided new insights into the relative inter-relationships among VFA measurements and also between VFA and CH yield. In conclusion, VFA molar proportions as represented by compositional balances were a significant contributor to explaining variation in CH yields from individual cattle.
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- 2017
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7. Considering appropriate replication in the design of animal social network studies
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I. M. Nevison, Michael R. Hutchings, Giles T. Innocent, Dave L. Swain, and Lesley A. Smith
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0301 basic medicine ,Statistical methods ,Social contact ,Behavioural ecology ,Computer science ,lcsh:Medicine ,Social behaviour ,Affect (psychology) ,Models, Biological ,Article ,Social Networking ,03 medical and health sciences ,0302 clinical medicine ,Animals ,lcsh:Science ,Social Behavior ,Social network analysis ,Statistical hypothesis testing ,Multidisciplinary ,Behavior, Animal ,Social network ,business.industry ,lcsh:R ,Replication (computing) ,030104 developmental biology ,Variation (linguistics) ,lcsh:Q ,Cattle ,business ,030217 neurology & neurosurgery ,Cognitive psychology - Abstract
Social network analysis has increasingly been considered a useful tool to interpret the complexity of animal social relationships. However, group composition can affect the contact structure of the network resulting in variation between networks. Replication in contact network studies is rarely done but enables determination of possible variation in response across networks. Here we explore the importance of between-group variability in social behaviour and the impact of replication on hypothesis testing. We use an exemplar study of social contact data collected from six replicated networks of cattle before and after the application of a social disturbance treatment. In this replicated study, subtle but consistent changes in animal contact patterns were detected after the application of a social disturbance treatment. We then quantify both within- and between-group variation in this study and explore the importance of varying the number of replicates and the number of individuals within each network, on the precision of the differences in treatment effects for the contact behaviour of the resident cattle. The analysis demonstrates that reducing the number of networks observed in the study would reduce the probability of detecting treatment differences for social behaviours even if the total number of animals was kept the same.
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- 2019
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8. Incidence and Distribution of Raspberry bushy dwarf virus in Commercial Red Raspberry (Rubus idaeus) Crops in Scotland
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A. M. I. Roberts, Wendy J. McGavin, Jane Chard, Susan Irvine, I. M. Nevison, and A Teifion Jones
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Blowing a raspberry ,Horticulture ,Shoot ,Botany ,food and beverages ,Sowing ,Plant Science ,Cultivar ,Biology ,Rubus ,biology.organism_classification ,Agronomy and Crop Science ,Virus - Abstract
A survey was done in 1998 to determine whether Raspberry bushy dwarf virus (RBDV) was established in raspberry fruiting plantations in Scotland. Raspberry-producing holdings were selected according to geographical area and size. Samples (201), each comprising 60 shoots per stock, were obtained from 77 holdings and tested by enzyme-linked immunosorbent assay (ELISA). ELISA-positive shoots from each infected stock were grafted onto cultivar Glen Clova, which is resistant to the Scottish-type isolate of RBDV (RBDV-S), to establish whether the virus is a resistance-breaking (RB) isolate. RBDV was detected in 22% of the stocks sampled, with 2 to 80% incidence of infection. No RBDV was in any of the 40 plantations containing cultivars resistant to RBDV-S or in Glen Clova plants, which were grafted successfully with samples from 15 infected plantations, indicating that no RB isolates were detected. The percentage of infected plantations increased with time from the planting date. In order to investigate possible sources of infection, ELISA for RBDV was made in 1999 on samples of stocks of raspberry cultivars entered for the lowest certified grade (Standard Grade) in Scotland and, in 1994 to 1997, on certified stocks planted with material originating from outside Scotland. No RBDV was detected in any of the samples. RBDV was found only rarely in samples of wild raspberry in Angus and Perthshire.
- Published
- 2019
9. Prediction of variety distinctness decisions under yearly heterogeneity
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T. Christie, A. M. I. Roberts, and I. M. Nevison
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0106 biological sciences ,False positives and false negatives ,Extension (predicate logic) ,Residual ,Variety (linguistics) ,01 natural sciences ,Cost savings ,Data set ,Set (abstract data type) ,Statistics ,Genetics ,Animal Science and Zoology ,Agronomy and Crop Science ,010606 plant biology & botany ,Inverse-gamma distribution ,Mathematics - Abstract
SUMMARYTo gain protection under the International Convention for the Protection of New Varieties of Plant, new plant varieties must be distinguishable from existing varieties in at least one important characteristic. Assessment of quantitative characteristics often uses a procedure based on analysis of variance of variety-by-year means for 2 years of trials. In the current paper, a new method is described that can identify those reference varieties that are so different from a candidate that there would be no reason to compare them in the subsequent year, resulting in potential cost savings. It is more objective and transparent than existing practice for quantitative characteristics based on expert opinion. The method calculates thresholds for quantitative characteristics. The thresholds are defined so that if in the first year the difference between two varieties in a characteristic is larger than the characteristic's threshold then it is highly likely that the varieties would be distinct after 2 years. Thresholds were derived based on statistical predictions of the full decision after 2 years using the first year results combined with historical data. It is shown that these thresholds are sensitive to yearly heterogeneity in the variety-by-year variation. The method accommodates this heterogeneity by modelling yearly residual variances with the inverse gamma distribution. This extension meant that exact analytical formulae were not available so an approximation was suggested. Using simulation it was found that the approximation was reasonable; for thresholds corresponding to a high probability of distinctness, the approximate thresholds were a little higher than required. The method was evaluated on a 19-year data set for field pea, comparing decisions based on first year thresholds with those based on the full 2 years. It was found that with the probability of distinctness set at 0·99, the calculated thresholds were generally lower than the existing expert-set thresholds but had acceptable levels of false positives and false negatives.
- Published
- 2016
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10. Evidence for litter differences in play behaviour in pre-weaned pigs
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Sarah Brown, Michael Klaffenböck, Alistair Lawrence, and I. M. Nevison
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Litter (animal) ,Sex effects ,BIRTH ,Ontogeny ,Birth weight ,Article ,Developmental psychology ,Growth development ,Animal science ,Ethogram ,Litter differences ,Post-natal ,Food Animals ,Weaning ,General activity ,Social play ,LAMBS ,WELFARE ,reproductive and urinary physiology ,PIGLETS ,Physical development ,Pig ,Spontaneous play behaviour ,ONTOGENY ,Pre-natal ,Individual differences ,GROUND-SQUIRRELS ,PERSONALITY-TRAITS ,SOWS ,Animal Science and Zoology ,WEIGHT ,MILK-PRODUCTION ,Psychology - Abstract
Highlights • First demonstration of between litter differences in play behaviour in pigs. • Litter differences in play behaviour appear independent of overall activity levels. • Litter differences in play behaviour associate strongly with post-natal growth. • Pre-natal factors (particularly birth weight and BMI) associate positively with play behaviour. • Pre-weaning play behaviour has potential as an indicator of positive welfare., The aim of this study was to analyse spontaneous play behaviour in litters of domestic pigs (Sus scrofa) for sources of variation at individual and litter levels and to relate variation in play to measures of pre and postnatal development. Seven litters of commercially bred piglets (n = 70) were born (farrowed) within a penning system (PigSAFE) that provided opportunities for the performance of spontaneous play behaviours. Individual behaviour was scored based on an established play ethogram for 2 days per week over the 3 week study period. We found strong evidence of litter differences in play behaviour (F(6,63) = 27.30, p
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- 2015
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11. Probing soil physical and biological resilience data from a broad sampling of arable farms in Scotland
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Susan Mitchell, Bryan S. Griffiths, Tracy A. Valentine, Kirsty Binnie, Adebayo J. Adeloye, Cathy Hawes, Sandra Caul, Rabee Rustum, I. M. Nevison, Paul D. Hallett, G. S. Squire, and Tim J. Daniell
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Land use ,Soil functions ,Soil water ,Sampling design ,Land management ,Soil Science ,Environmental science ,Soil science ,Soil carbon ,Arable land ,Soil type ,Pollution ,Agronomy and Crop Science - Abstract
Physical and biological soil stabilities (i.e. resistance and resilience) were measured on a range of arable farms across eastern Scotland under a range of management practices, with the objective of using a geographically restricted set of soils under similar land use to detect any underlying associations between soil stability, management factors and soil properties. Data were analysed using a combination of a stepwise fixed effects model selection within a linear mixed-model framework (LMM) and neural network analysis using a Kohonen self-organising map (KSOM). In general, physical and biological measures of stability were associated with both physical and biological soil properties, particularly bulk density, water retention characteristics, soil carbon and bacterial community structure. A strength of KSOM is its ability to fit more flexible models than the linear relationships of LMM. However, a weakness is that it does not have the ability of LMM to model the sampling design, which is likely to lead to overstating statistical significance. Consequently, KSOM identified more significant associations between soil properties and stability than LMM, while the latter identified significant associations at the between-farm level. The high-level land management decisions of farm type (conventional, organic, integrated), crop type or underlying soil type were not associated with stability at this regional scale, thus indicating that the effects of different management practices between farms were overridden by the soil properties on each farm. Management decisions on improving soil stability therefore need to be taken at the individual field scale.
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- 2015
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12. Playful pigs: Evidence of consistency and change in play depending on litter and developmental stage
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S M, Brown, R, Peters, I M, Nevison, and A B, Lawrence
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Litter differences ,Play ,Piglet ,Weaning ,Growth ,reproductive and urinary physiology ,Article - Abstract
Highlights • Litter differences in play behaviour occur pre- and post-weaning. • More than 25% of the variance in locomotor play was attributable to the litter. • 'Non harmful fighting’ was unique in showing consistency pre- to post-weaning. • Litters differ in their locomotor play response to weaning (‘litter weaning effect’). • Suggests a ‘common factor’ at the litter level creating variation in locomotor play., Play behaviour in pre-weaned piglets has previously been shown to vary consistently between litters. This study aimed to determine if these pre-weaning litter differences in play behaviour were also consistent in the post-weaning period. Seven litters of commercially bred piglets were raised in a free farrowing system (PigSAFE) and weaned at 28 days post-farrowing (+/−2 days). Post-weaning piglets were maintained in litter groups in the PigSAFE pen. Analyses have been adjusted for sex both within and between litter as the only statistically significant covariate to play behaviour. Litter differences were observed in locomotor play in both the pre- and post-weaning stage (Pre: F(6,76) = 5.51 P
- Published
- 2018
13. Compositional mixed modeling of methane emissions and ruminal volatile fatty acids from individual cattle and multiple experiments
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J, Palarea-Albaladejo, J A, Rooke, I M, Nevison, and R J, Dewhurst
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Male ,Butyrates ,Rumen ,Fermentation ,Linear Models ,Animals ,Cattle ,Female ,Acetates ,Propionates ,Fatty Acids, Volatile ,Methane ,Diet - Abstract
The aim of the study was to investigate the association of methane (CH) yields (g/kg DMI) with rumen VFA molar proportions and animal and diet-related covariates from individual animals and multiple experiments. The dataset available consisted of 284 measurements of CH yields for beef cattle from 6 experiments measured in indirect respiration chambers. A compositional modeling approach was employed where VFA measurements were considered as a whole, instead of in isolation, emphasizing their multivariate relative scale. The analysis revealed expected close groupings of acetate and butyrate; propionate and valerate; iso-butyrate and iso-valerate. Linear mixed models were then fitted to examine relationships between CH yield and VFA, represented by meaningful log-contrasts of components called compositional balances, while accounting for other animal and diet-related covariates and random variability between experiments. A compositional balance representing (acetate × butyrate)/propionate best explained the contribution of VFA to variation in CH yield. The covariates DMI, forage:concentrate proportion (expressed as a categorical variable diet type: high concentrate, mixed forage:concentrate or high forage), and diet ME were also statistically significant. These results provided new insights into the relative inter-relationships among VFA measurements and also between VFA and CH yield. In conclusion, VFA molar proportions as represented by compositional balances were a significant contributor to explaining variation in CH yields from individual cattle.
- Published
- 2017
14. Seasonal nitrous oxide emissions from field soils under reduced tillage, compost application or organic farming
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Christine A. Watson, Paul D. Hallett, Robin L. Walker, Bruce C. Ball, Blair M. McKenzie, I. M. Nevison, Robert M. Rees, Helen Gordon, Bryan S. Griffiths, Ron E. Wheatley, and C. F. E. Topp
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business.product_category ,Ecology ,Crop rotation ,Manure ,Plough ,Minimum tillage ,Tillage ,Soil management ,No-till farming ,Agronomy ,Organic farming ,Environmental science ,Animal Science and Zoology ,business ,Agronomy and Crop Science - Abstract
Soil management practices shown to increase carbon sequestration include reduced tillage, amendments of carbon and mixed rotations. As a means to mitigate greenhouse gases, however, the success of these practices will be strongly influenced by nitrous oxide (N 2 O) emissions that vary with soil wetness. Few seasonal data are available on N 2 O under different soil managements so we measured seasonal N 2 O emission in three field experiments between 2006 and 2009 in eastern Scotland. The experimental treatments at the three sites were (1) tillage: no-tillage, minimum tillage, ploughing to 20 cm with or without compaction and deep ploughing to 40 cm, (2) organic residue amendment: application of municipal green-waste compost or cattle slurry and (3) rotations: stocked and stockless (without manure) organic arable farming rotations. Most seasons were wetter than average with 2009 the wettest, receiving 20–40% more rainfall than average. Nitrous oxide emissions were measured using static closed chambers. There was no statistical evidence, albeit with low statistical power, that reduced tillage affected N 2 O emissions compared to normal depth ploughing. With organic residue amendments, only in the wet season in 2008 were emissions significantly increased by high rates of green-waste compost (4.5 kg N 2 O-N ha −1 ) and cattle slurry (5.2 kg N 2 O-N ha −1 ) compared to the control (1.9 kg N 2 O-N ha −1 ). In the organic rotations, N 2 O emissions were greatest after incorporation of the grass/clover treatments, especially during conversion of a stocked rotation to stockless. Emissions from the organic arable crops (1.9 kg N 2 O-N ha −1 in 2006, 3.0 kg N 2 O-N ha −1 in 2007) generally exceeded those from the organic grass/clover (0.8 kg N 2 O-N ha −1 in 2006, 1.1 kg N 2 O-N ha −1 in 2007) except in 2008 when the wet weather delayed manure applications and increased emissions from the grass/clover (2.8 kg N 2 O-N ha −1 ). Nevertheless, organic grassland was the land use providing the most effective overall mitigation. Although the magnitude of fluxes did not relate particularly well to rainfall differences between seasons, greater rainfall received during some growing seasons increased the differences between tillage, organic residue and crop rotation phase treatments, negating any possible mitigation by timing management operations in dry periods. This was partly attributed to applying tillage and manures late and/or in wet conditions. Of benefit would be different sampling strategies including closed chambers or eddy covariance with standardised methodology. Controlled soil management experiments with a wide geographic spread to specify land management for mitigation also important.
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- 2014
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15. Methane emissions from beef and dairy cattle: Quantifying the effect of physiological stage and diet characteristics1
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Anthony Waterhouse, John Rooke, P. Ricci, and I. M. Nevison
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Methane emissions ,business.industry ,Climate change ,General Medicine ,Agronomy ,Agriculture ,Greenhouse gas ,Grazing ,Genetics ,Herd ,Environmental science ,Animal Science and Zoology ,Stage (hydrology) ,business ,Dairy cattle ,Food Science - Abstract
The prediction of methane outputs from ruminant livestock data at farm, national, and global scales is a vital part of greenhouse gas calculations. The objectives of this work were to quantify the effect of physiological stage (lactating or nonlactating) on predicting methane (CH4) outputs and to illustrate the potential improvement for a beef farming system of using more specific mathematical models to predict CH4 from cattle at different physiological stages and fed different diet types. A meta-analysis was performed on 211 treatment means from 38 studies where CH4, intake, animal, and feed characteristics had been recorded. Additional information such as type of enterprise, diet type, physiological stage, CH4 measurement technique, intake restriction, and CH4 reduction treatment application from these studies were used as classificatory factors. A series of equations for different physiological stages and diet types based on DMI or GE intake explained 96% of the variation in observed CH4 outputs (P
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- 2013
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16. Power calculations for monitoring studies: a case study with alternative models for random variation
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I. M. Nevison, A.R.J. Sier, Michael D. Morecroft, David A. Elston, and W. A. Scott
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Statistics and Probability ,Formal power series ,Abundance (ecology) ,Ecological Modeling ,Power calculations ,Statistics ,Autocorrelation ,Econometrics ,Magnitude (mathematics) ,Variance components ,Random variable ,Term (time) ,Mathematics - Abstract
Statistical assessment of any monitoring scheme should always take place ahead of its implementation, and formal power calculations play an important role in such assessments. The power calculations can either be used to help find a design with a stated probability of detecting a given trend or difference in trends at some level of significance, or they can be used to provide information about the magnitude of trend or difference in trends which is likely to be detected by a proposed monitoring scheme. In either case, the power calculations require estimates of variances or variance components. This paper describes a case study in which statistical powers are compared for two competing models for random variation over years within sites: a random regression coefficient model, and a first order autocorrelated error model. The response variables we present results for are unconstrained indices of butterfly abundance and constrained indices of plant species composition. The results indicate the effect of the different assumptions about random variation, in both the short and the long term.
- Published
- 2011
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17. The effect of perceived environmental background on qualitative assessments of pig behaviour
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Françoise Wemelsfelder, I. M. Nevison, and Alistair Lawrence
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media_common.quotation_subject ,Free-choice profiling ,Novel object ,Applied psychology ,Generalized Procrustes analysis ,Analyse qualitative ,Body language ,Qualitative analysis ,Personality ,Animal Science and Zoology ,Psychology ,Social psychology ,Ecology, Evolution, Behavior and Systematics ,media_common - Abstract
Qualitative behaviour assessment is an integrative methodology that characterizes behaviour as a dynamic, expressive body language (e.g. as anxious or content). Such assessments are sensitive to environmental context, which makes them informative but also vulnerable to observers' biased views of that context. This study investigated whether and how perceived environmental background affects observers' qualitative assessments of pig, Sus scrofa , behaviour. Fifteen growing pigs were filmed individually against a neutral background while interacting with a novel object. The footage of each pig was digitally isolated from that background and pasted against indoor and outdoor backgrounds filmed in real time. The 30 video clips thus obtained were shown to 16 observers, who were led to believe these were 30 different pigs filmed in either an indoor or an outdoor pen. Free-choice profiling was used to instruct observers in qualitative behaviour assessment, and data were analysed with generalized Procrustes analysis. Analysis of variance found a significant effect of environmental background on pig scores on the second consensus dimension (confident/content–cautious/nervous), but not on the first (playful/active–bored/lethargic). However, 95% confidence intervals and indexes for the variability attributable to environmental background, calculated for both consensus dimensions, indicated that any such effects should be relatively small. High correlations were found between indoor and outdoor pig scores on both consensus dimensions ( r ≥ 0.95). Together these results suggest that environmental background may slightly shift, but is unlikely to seriously distort, observer characterizations of pig expression. Last, we discuss possible strategies for reducing the effect of contextual bias on qualitative behaviour assessment.
- Published
- 2009
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18. CONSTRUCTION OF SENSORY VOCABULARIES FOR PROFILING FOOD
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I. M. Nevison and D. Donald Muir
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Statistics ,Profiling (information science) ,Sensory system ,Wine tasting ,Social psychology ,Sensory Systems ,Food Science ,Mathematics - Abstract
Sensory profiling laboratories rate products for sets of attributes. Order of tasting and carry-over effects from sample to sample are widely recognized. However, within samples, work investigating the possibility of effects due to the order of rating attributes and attribute to attribute carry-over has not been reported. Individual attributes were classified according to whether their presence in a product was perceived to be desirable or not. For both yoghurt and cheese, sample ratings for each attribute were compared when attributes perceived as desirable preceded those perceived as undesirable and vice-versa. In both stimuli, there was evidence that desirable attributes were biased to a lower value when preceded by undesirable ones. Similarly, negative attributes were biased downwards when preceded by desirable ones. For absolute scores, these effects, albeit small, make randomizing attribute ordering desirable. However, lack of evidence of interactions between samples and attribute ordering suggests comparative differences between samples are unaffected.
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- 2002
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19. The effect of treating seed potato tubers with benzimidazole, imidazole and phenylpyrrole fungicides on the control of rot and skin blemish diseases
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E. Sharp, I. M. Nevison, D. A. Lindsay, A. M. Cameron, and S. F. Carnegie
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Helminthosporium solani ,biology ,food and beverages ,Phoma exigua ,Fusarium dry rot ,biology.organism_classification ,Polyscytalum pustulans ,Fungicide ,chemistry.chemical_compound ,Horticulture ,medicine.drug_formulation_ingredient ,chemistry ,Seed treatment ,Botany ,medicine ,Phoma exigua var. foveata ,Dry rot ,Agronomy and Crop Science - Abstract
Summary. Over 6 yr the effectiveness of imazalil, prochloraz and fenpiclonil, applied either alone or in a mixture, in controlling gangrene, dry rot, skin spot and silver scurf on potato tubers in store was compared with that of 2-aminobutane and thiabendazole. An assessment was also made of their efficiency in controlling the development of these diseases on the daughter tubers of seed tubers treated at harvest or before planting. Overall, 2-aminobutane was more effective in controlling gangrene (Phoma foveata) in store than the spray-applied fungicides. Deposits of imazalil, thiabendazole and fenpiclonil were greater when sprays were applied with an electrostatic sprayer than with a hydraulic sprayer. The opposite was found with the mixture of prochloraz Mn and tolclofos-methyl. More effective gangrene control was associated with the highest deposits. Fenpiclonil and the mixture of thiabendazole and imazalil were more effective in controlling dry rot (Fusarium solani var. coeruleum) than imazalil alone. The development of dry rot was, however, increased by 2-aminobutane treatment on eight out of 14 stocks. 2-aminobutane gave the greatest reduction (83%) in the severity of skin spot during storage whereas thiabendazole alone, and the mixture of thiabendazole and imazalil, gave mean reductions of 70% and 65% respectively. This mixture and fenpiclonil gave the greatest reduction in the severity of silver scurf although, in general, reductions in silver scurf with fungicide treatment were less than with skin spot. The type of sprayer used to apply a fungicide did not affect the effectiveness of the fungicides in controlling either skin spot or silver scurf on tubers in store, or on the daughter tubers. The incidence of gangrene and dry rot on daughter tubers was not reduced consistently by fungicide treatment of seed tubers of the six stocks tested. However, the severity of skin spot and silver scurf was reduced by fungicide treatments of all eight stocks but the reduction in disease was greater for skin spot than for silver scurf. All fungicides gave reductions in the severity of skin spot, and fenpiclonil and the mixture of thiabendazole and imazalil were the most effective for silver scurf. The effectiveness of the fungicides in controlling these diseases was similar for seed treated at harvest and that treated before planting.
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- 1998
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20. Parturient hypocalcaemia in dairy cows: effects of dietary acidity on plasma minerals and calciotrophic hormones
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M. Phillippo, G.W. Reid, and I. M. Nevison
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medicine.medical_specialty ,Silage ,chemistry.chemical_element ,Parathyroid hormone ,Plasma chloride ,Phosphates ,Calcitriol ,Pregnancy ,Internal medicine ,medicine ,Animals ,Magnesium ,Hypocalcaemia ,Analysis of Variance ,Labor, Obstetric ,Hypocalcemia ,General Veterinary ,Chemistry ,Phosphorus ,Hydrogen-Ion Concentration ,medicine.disease ,Animal Feed ,Pregnancy Complications ,Endocrinology ,Parathyroid Hormone ,Pregnancy, Animal ,Calcium ,Cattle ,Female ,Hormone - Abstract
Mature Friesian cows were given silage plus either an alkaline or an acidic concentrate mix during the last 28 days of pregnancy in two experiments. There were no significant differences in plasma calcium, phosphorus or magnesium concentrations before parturition but the blood ionised calcium and plasma chloride concentrations were significantly increased, together with a lower blood pH and acid-base excess in the cows on the acid diet. The mean 1,25-dihydroxyvitamin D concentrations tended to increase before parturition in the cows on the acid diet compared with the alkali diet in experiment 1 and were significantly higher in experiment 2. At parturition, the acid-fed cows had higher mean plasma calcium concentrations and significantly more of them had values >2·0 mmol litre−1 than the alkali-fed groups, and the plasma 1,25-dihydroxyvitamin D and parathyroid hormone concentrations were related to these different plasma calcium concentrations. The acidic diets therefore appeared to prevent the onset of hypocalcaemia at parturition by increasing the plasma 1,25-dihydroxyvitamin D concentration before parturition.
- Published
- 1994
- Full Text
- View/download PDF
21. Genotypic effects of the Texel Muscling QTL (TM-QTL) on meat quality in purebred Texel lambs
- Author
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I. M. Nevison, N. R. Lambe, Lutz Bünger, Oswald Matika, J. M. Macfarlane, R. I. Richardson, and W. Haresign
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Male ,Veterinary medicine ,Heterozygote ,Meat ,Food Handling ,Quantitative Trait Loci ,Quantitative trait locus ,Biology ,Breeding ,Fats ,Animal science ,Genotype ,Animals ,Crosses, Genetic ,Sheep, Domestic ,Netherlands ,Muscles ,Chromosomes, Mammalian ,Taste ,Odorants ,Regression Analysis ,Female ,Texel ,Meat science ,Purebred ,Food Science ,Microsatellite Repeats - Abstract
Texel Muscling QTL (TM-QTL) increases loin muscling in lambs inheriting it from their sire only. This study investigated TM-QTL effects on meat quality in 209 Texel lambs that were CT-scanned then slaughtered at 20weeks (carcasses aged for ~1week). Loin meat quality traits included: CT-measured muscle density (predicting intramuscular fat); mechanical tenderness using Volodkevich-type jaws or MIRINZ tenderometer; intramuscular fat; sensory eating quality (sub-sample of 40 lambs). Volodkevich tenderness was also measured in the leg (Vastis lateralis). TM-QTL genotypes were determined, giving 40 non-carriers (+/+), 70 heterozygotes-53 inheriting TM-QTL from the sire (TM/+) and 17 from the dam (+/TM), 34 homozygote TM-QTL lambs (TM/TM) and 65 uncertain. Multiple regression identified no genotype effects on meat quality. For MIRINZ-measured loin tenderness only, contrasts revealed a significant additive effect of TM-QTL (1.27kgF difference between homozygotes). However, the taste panel identified no significant differences between +/+ and TM/TM lambs. Results show little evidence of TM-QTL affecting meat quality.
- Published
- 2010
22. The effect of active immunization against gonadotropin-hormone-releasing-hormone on growth performance and sample joint composition of bulls
- Author
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Gerald Lobley, P. E. V. Williams, B. A. Morris, R. Anderson, J. Clayton, Alexmary Connell, and I. M. Nevison
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medicine.drug_class ,Biology ,Active immunization ,Titer ,Animal science ,biology.protein ,medicine ,Animal Science and Zoology ,Composition (visual arts) ,Antibody ,medicine.symptom ,Gonadotropin ,Weight gain ,Testosterone ,Hormone - Abstract
Forty-six Simmental × British Friesian bull calves were allocated to six treatment groups. In four groups (each of eight animals) half the animals were given a prime injection of gonadotropin-hormone-releasing-hormone (GnRH) either as the decapeptide or as an octapeptide (residues 3 to 10) conjugated to egg albumen. Prime injection times were at 3, 4, 5 or 6 months of age. All animals were boosted with a GnRH conjugate, similar to that used for the prime injection, at 8 months. At 8 months, six other animals were surgically castrated while the remaining eight were left as untreated bull controls. Weight gain and consumption of a barley-based diet offered ad libitum were recorded for individual animals. Blood samples were taken at a minimum of fortnightly intervals and the serum analysed for antibody titre against GnRH, testosterone and insulin-like growth factor 1 (IGF-1). Animals were slaughtered at 12 months and chemical analyses performed on the dissectible material of the 10th rib for protein, lipid, ash and water content. Greater antibody titres and a longer period of low serum testosterone were achieved with the octapeptide conjugate compared with the decapeptide. Serum IGF-1 slowly decreased following both surgical- and effective immuno-castration. There were no significant differences in food intake between the groups. Both steers and the more responsive immunocastrates had higher fat (P < 0·01), lower protein (P < 0·05) and water concentrations (P < 0·01) in tissues from a rib sample joint compared with untreated bulls. As immuno-responsiveness decreased there were indications of compensatory changes in body composition. The technique may be applicable during periods of, for example, mixed grazing for bulls.
- Published
- 1992
- Full Text
- View/download PDF
23. Investigating the behavioural and physiological indicators of neonatal survival in pigs
- Author
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Emma M. Baxter, I. M. Nevison, Richard B. D’Eath, Marianne Farish, Sheena K. Robson, D.W. Ross, Alistair Lawrence, Sandra Edwards, and Susan Jarvis
- Subjects
Pediatrics ,medicine.medical_specialty ,Survival ,Swine ,animal diseases ,Birth weight ,Placenta ,Physiology ,Crown-Rump Length ,fluids and secretions ,Food Animals ,Pregnancy ,medicine ,Animals ,Birth Weight ,Small Animals ,Fetal Death ,Crown-rump length ,integumentary system ,Behavior, Animal ,Equine ,business.industry ,Neonatal survival ,medicine.disease ,Low birth weight ,Birth order ,Animals, Newborn ,Colostrum ,Animal Science and Zoology ,Female ,medicine.symptom ,business ,Body mass index ,Body Temperature Regulation - Abstract
Survival is reduced in low birth weight piglets, which display poor thermoregulatory abilities and are slow to acquire colostrum. Our aim was to identify additional behavioural and physiological indicators of piglet survival incorporating traits reflective of both the intrauterine and extrauterine environment. Data were collected from 135 piglets from 10 Large White x Landrace sows to investigate which physiological measurements (e.g. individual placental traits), and which behavioural measurements (e.g. the quantification of piglet vigour), were the best indicators of piglet survival. Generalised linear models confirmed piglet birth weight as a critical survival factor. However, with respect to stillborn mortality, piglet shape and size, as measured by ponderal index (birth weight/(crown-rump length)(3)), body mass index (birth weight/(crown-rump length)(2)), respectively, and farrowing birth order were better indicators. With respect to live-born mortality, postnatal survival factors identified as crucial were birth weight, vigour independent of birth weight, and the latency to first suckle. These results highlight the importance of the intrauterine environment for postnatal physiological and behavioural adaptation and identify additional factors influencing piglet neonatal survival.
- Published
- 2007
24. Circadian variation in heart rate, blood pressure, body temperature and EEG of immature broiler breeder chickens in restricted-fed and ad libitum-fed states
- Author
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C.J. Savory, I. M. Nevison, and L. Kostal
- Subjects
medicine.medical_specialty ,Blood Pressure ,Electroencephalography ,Broiler breeder ,Biology ,Food ration ,Body Temperature ,Animal science ,Heart Rate ,Internal medicine ,Heart rate ,medicine ,Animals ,Circadian rhythm ,Animal Husbandry ,medicine.diagnostic_test ,Body Weight ,Broiler ,General Medicine ,Sleep in non-human animals ,Circadian Rhythm ,Blood pressure ,Endocrinology ,Animal Science and Zoology ,Animal Nutritional Physiological Phenomena ,Female ,Food Deprivation ,Chickens ,Food Science - Abstract
1. Heart rate, intra-aortic blood pressure, deep body temperature and telencephalic EEG were monitored by radiotelemetry in 6 freely moving immature broiler breeders (three in each of two years), during routine food restriction and then ad libitum feeding, over two 24-h periods in each feeding state.2. Heart rate, blood pressure and body temperature were all higher during ad libitum than restricted feeding, and heart rate and body temperature were higher by day (12 h) than at night (12 h). The decreases in heart rate and body temperature at night were greater during restricted than ad libitum feeding. Blood pressure tended to be higher at night, except in year 2 during restricted feeding. Body temperature and ambient temperature were higher in year 2 than year 1.3. During restricted feeding, marked peaks in heart rate, blood pressure and body temperature in the 15 min after provision of the daily food ration at 09:00 h, when birds were eating, were equivalent to corresponding values seen during ad libitum feeding.4. Relative powers in delta (1 to 4 Hz) and theta (4 to 8 Hz) frequency bands of the EEG power spectrum were higher at night in year 2 only, while power in the alpha (8 to 12 Hz) band was higher at night in both years.5. It is concluded that most of the variation in heart rate, blood pressure and body temperature between feeding states and times of day/night can be accounted for in terms of variation in food intake and energy expenditure. The greater slow wave (delta, theta) EEG activity seen after lights-off in year 2 may reflect non-paradoxical sleep at that time.
- Published
- 2006
25. Metabolic safety-margins do not differ between cows of high and low genetic merit for milk production
- Author
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Richard G. Vernon, I. M. Nevison, Christopher H. Knight, Annette Sorensen, David J. Flint, and Mohammed Alamer
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medicine.medical_specialty ,medicine.medical_treatment ,Biology ,Selective breeding ,Milking ,Heart Rate ,Internal medicine ,Lactation ,Heart rate ,medicine ,Animals ,Insulin ,Bovine somatotropin ,Insulin-Like Growth Factor I ,Dairy cattle ,Body Weight ,General Medicine ,Milk production ,Thyroxine ,Endocrinology ,medicine.anatomical_structure ,Growth Hormone ,Body Composition ,Regression Analysis ,Animal Science and Zoology ,Cattle ,Female ,Food Science - Abstract
Three galactopoietic stimuli, frequent milking (4X), bovine somatotrophin (bST) and thyroxine (T4) were used in an additive stair-step design to achieve maximum output (metabolic capacity) in six peak-lactation cows of high genetic merit (HT) and six of low genetic merit (LT). A further six of each merit were untreated controls (HC, LC). Milk yield was increased significantly by 4X, increased further by the combination of 4X and bST and increased further still and significantly by the full combination of 4X, bST and T4. The magnitude of the yield response to the sequence of treatments did not differ significantly between HT and LT. The yield response to 4X and bST was sustainable without significant loss of body weight or body condition score for the 6 weeks during which these stimuli were administered. The response to the full combination, which included T4, was accompanied by significantly elevated heart rate and significant loss of body weight and condition compared with the combination of 4X and bST. As a result, treatments were discontinued, on an individual cow basis, before completion of this 6-week phase. Time on experiment did not differ between HT and LT. The results do not support the commonly held belief that selective breeding of dairy cows for high milk production has rendered them markedly more susceptible to metabolic disturbances.
- Published
- 2004
26. Effects of amino acid nutrition on the responses of dairy cows to milking more frequently with or without injection of growth hormone
- Author
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J.-M. Yeo, I. M. Nevison, D.G. Chamberlain, and Christopher H. Knight
- Subjects
medicine.medical_specialty ,Time Factors ,Silage ,Lactose ,Biology ,Fatty Acids, Nonesterified ,Poaceae ,Milking ,Fish meal ,Animal science ,Mammary Glands, Animal ,Internal medicine ,Lactation ,Genetics ,medicine ,Animals ,Udder ,Amino Acids ,Insulin-Like Growth Factor I ,Dairy cattle ,Feather meal ,food and beverages ,Methylhistidines ,Milk Proteins ,Diet ,Growth hormone treatment ,Dairying ,medicine.anatomical_structure ,Endocrinology ,Milk ,Creatinine ,Growth Hormone ,Animal Science and Zoology ,Animal Nutritional Physiological Phenomena ,Cattle ,Female ,Blood Flow Velocity ,Food Science - Abstract
The influence of amino acid nutrition on the response to milking more frequently, with or without injection of growth hormone, was examined in eight dairy cows in two 4 x 4 Latin squares with 28-d periods. The four treatments were a diet adequate in amino acids with or without injection of growth hormone and a diet inadequate in amino acids with or without injection of growth hormone. For all four treatments, during the last 14 d of each period, one half of the mammary gland was milked three times a day (3x), while the other half remained on twice-daily milking (2x). Both diets were based on grass silage given ad libitum and 4 kg/d of sugar beet pulp together with a supplement containing either fish meal (adequate diet) or feather meal (inadequate diet) as the only protein feeds. The diet containing feather meal is known to be deficient in His, Met, and Lys. On the fish meal diet, the cows responded positively to growth hormone and to milking more frequently and the responses to both treatments were additive. On the feather meal diet, however, even though injection of growth hormone increased the yield of milk protein by around 10%, milking more frequently did not affect milk production. It is concluded that milking more frequently has a weaker effect on the partitioning of amino acid use between body and udder than does growth hormone treatment.
- Published
- 2003
27. Parameter Estimators for Gaussian Models with Censored Time Series and Spatio-temporal Data
- Author
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I. M. Nevison, Chris A. Glasbey, and A. G. M. Hunter
- Subjects
symbols.namesake ,Fourier transform ,Series (mathematics) ,Gaussian ,Statistics ,symbols ,Estimator ,Latent variable ,Missing data ,Environmental data ,Mathematics ,Temporal database - Abstract
Computationally-fast algorithms are considered for estimating parameters in Gaussian time series and spatio-temporal models from censored and/or missing data. The problem arises in fitting models involving Gaussian latent variables to environmental data. Spectral estimators and least-squares fits of auto- and cross-covariances are found to be of similar efficiency for fitting models to rainfall and solar radiation data.
- Published
- 1998
- Full Text
- View/download PDF
28. Rainfall Modelling Using a Latent Gaussian Variable
- Author
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I. M. Nevison and Chris A. Glasbey
- Subjects
Statistics::Applications ,Gaussian ,media_common.quotation_subject ,Monotonic function ,Latent variable ,Hourly rainfall ,Physics::Geophysics ,Variable (computer science) ,symbols.namesake ,Goodness of fit ,Statistics ,Econometrics ,symbols ,Physics::Atmospheric and Oceanic Physics ,Normality ,Mathematics ,media_common ,Gibbs sampling - Abstract
A monotonic transformation is applied to hourly rainfall data to achieve marginal normality. This defines a latent Gaussian variable, with zero rainfall corresponding to censored values below a threshold. Autocorrelations of the latent variable are estimated by maximum likelihood. The goodness of fit of the model to Edinburgh rainfall data is comparable with that of existing point process models. Gibbs sampling is used to disaggregate daily rainfall data, to generate typical hourly data conditional on daily totals.
- Published
- 1997
- Full Text
- View/download PDF
29. Designs for controlling interplot competition in variety trials
- Author
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R. A. Kempton, I. M. Nevison, O. David, Unité de recherche Biométrie (UB), and Institut National de la Recherche Agronomique (INRA)
- Subjects
Competition (economics) ,Computer science ,DISPOSITIF EXPERIMENTAL ,[SDV]Life Sciences [q-bio] ,Genetics ,Econometrics ,Animal Science and Zoology ,Agronomy and Crop Science ,Intraspecific competition ,Variety (cybernetics) - Abstract
SUMMARYInterplot competition in crop variety trials leads to biased estimates of variety differences. Modified alpha designs are proposed which aim to control competition by restricting the randomization so that adjacent varieties show similar competition effects. The designs are available in the computer program Alpha +.
- Published
- 1996
30. Clenbuterol, a beta-adrenoceptor agonist, increases relative muscle strength in orthopaedic patients
- Author
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I M Nevison, J S Watson, Charlotte A. Maltin, P H Gibson, Margaret Inkster Delday, I K Ritchie, and Steven D. Heys
- Subjects
Adult ,Male ,medicine.medical_specialty ,Knee Joint ,medicine.medical_treatment ,Placebo ,Menisci, Tibial ,law.invention ,Atrophy ,Randomized controlled trial ,Double-Blind Method ,law ,medicine ,Humans ,Clenbuterol ,Chemotherapy ,business.industry ,Muscles ,Skeletal muscle ,General Medicine ,medicine.disease ,Surgery ,Tibial Meniscus Injuries ,Muscular Atrophy ,medicine.anatomical_structure ,Anesthesia ,Muscle strength ,β adrenoceptor agonist ,business ,medicine.drug ,Muscle Contraction - Abstract
1. The sympathomimetic agent clenbuterol has a muscle-specific anabolic effect in normal and wasted muscles from animals. This trial was designed to examine the effect of the drug on the recovery of muscle strength and area after open medial meniscectomy. 2. A double-blind, completely randomized, placebo-controlled study was carried out on 20 healthy male patients. Muscle strength and cross-sectional area were determined before and after surgery. Patients were treated with drug or placebo for 4 weeks postoperatively and there was a 2 week washout period. 3. The results suggest that, in the operated leg, clenbuterol treatment is associated with a more rapid rehabilitation of strength in knee extensor muscles; in the unoperated leg, knee extensor strength increased above the initial values after 6 weeks (P = 0.01). However, in terms of absolute strength the differences were not significant between the two groups. 4. It is concluded that the data lend support to the proposition that clenbuterol has therapeutic potential in the treatment of muscle-wasting conditions.
- Published
- 1993
31. Responses in tissue protein synthesis to sub- and supra-maintenance intake in young growing sheep: comparison of large-dose and continuous-infusion techniques
- Author
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Alexmary Connell, David Stanley Brown, Gerald Lobley, Eric Milne, Patricia M. Harris, Peter J. Garlick, Susan E. Anderson, I. M. Nevison, Pat A. Skene, and A. G. Calder
- Subjects
Male ,medicine.medical_specialty ,Continuous infusion ,Phenylalanine ,Medicine (miscellaneous) ,Tissue protein ,Muscle Proteins ,Biology ,Leucine ,Internal medicine ,Protein biosynthesis ,medicine ,Animals ,Infusions, Intravenous ,Skin ,Gastrointestinal tract ,Nutrition and Dietetics ,Sheep ,Dose-Response Relationship, Drug ,Metabolism ,Venous blood ,Endocrinology ,Liver ,Protein Biosynthesis ,Dietary Proteins - Abstract
In ten lambs (average live weight 33 kg), five offered 300 g/d (approximately 0.6 x maintenance; L) and five 900 g/d (1.8 x maintenance; H), tissue protein synthesis was measured by three procedures simultaneously. The techniques involved continuous infusion of [U-14C]phenylalanine and [1-13C]leucine over 7–8 h followed by a terminal large dose of [15N]phenylalanine during the last 30 or 60 min. Rates of protein synthesis were then calculated based on the free amino acid or oxo-acid isotopic activity in either arterial, iliac venous blood or tissue homogenate for the continuous-infusion studies, or on plasma or tissue homogenate for the large-dose procedure. For muscle (> 99%), and to a lesser extent skin (85–93%), effective flood conditions were achieved with the [15N]phenylalanine but were either not established or maintained for liver and tissues of the gastrointestinal tract (< 50%). The large dose of phenylalanine also caused changes in the concentration and isotopic activity of blood leucine and 4-methyl-2-oxo-pentanoate. Based on the assumption that the large-dose procedure yields the closest value for the true rate of protein synthesis (L 1.97%/d, H 2.85%/d) then, for muscle, only values based on the homogenate as precursor gave comparable results for both leucine (L 1.83%/d, H 3.01%/d) and phenylalanine (L 1.67%/d, H 2.71%/d) continuous infusion. The values based on the arterial or venous amino or oxo-acid were significantly less, more so at the lower intake. In contrast, for skin, a tissue dominated by export protein synthesis, values from the large-dose procedure (L 6.37%/d, H 10.98%/d) were similar to those derived with arterial or venous metabolites as precursor (L 5.23 and 6.93%/d, H 9.98 and 11.71%/d for leucine), but much less than those based on homogenate data. Based on the large-dose technique, protein synthesis increased with intake in muscle (P< 0.001), skin (P= 0.009) and liver (26.7v.30.5%/d;P= 0.029). The contributions of muscle and skin to total protein synthesis were approximately equal. The incremental efficiency of conversion for muscle of synthesized protein into deposition appeared to be similar to values reported for rodents
- Published
- 1992
32. Polyamine metabolism and uptake during Phaseolus vulgaris lectin, PHA-induced growth of rat small intestine
- Author
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Susan Bardocz, S.w.b. Ewen, George Grant, Arpad Pusztai, David Stanley Brown, and I. M. Nevison
- Subjects
Male ,Stimulation ,chemistry.chemical_compound ,Intestine, Small ,medicine ,Extracellular ,Animals ,Phytohemagglutinins ,Kidney ,Hyperplasia ,biology ,Polyamine transport ,Biogenic Polyamines ,Gastroenterology ,Lectin ,Biological Transport ,Hypertrophy ,Adaptation, Physiological ,Small intestine ,Stimulation, Chemical ,Rats ,medicine.anatomical_structure ,Biochemistry ,chemistry ,biology.protein ,Polyamine - Abstract
Kidney bean lectin, PHA, stimulated the hyperplastic and hypertrophic growth of rat small intestine. This growth was preceded by a rapid accumulation of polyamines in the small intestine. However, since the lectin had little effect on in situ polyamine biosynthesis, most of the polyamines must have been of extracellular origin. To investigate the source of polyamines, both the luminal uptake and basolateral transport of polyamines by the rat small intestine were measured in vivo. Luminal polyamine uptake was apparently by passive diffusion, non-saturable, linearly dependent on concentration and its extent was not stimulated by PHA. In contrast, 14C-polyamines injected intraperitoneally were probably taken up by a transport system(s). Moreover, basolateral polyamine transport was stimulated in a time-dependent manner when small intestinal growth was stimulated by PHA. However, in keeping with the finding of polyamine accumulation prior to demonstrable growth of the tissue, stimulation by PHA of the polyamine transport system also preceded small intestinal growth. Stimulation of polyamine transport by luminal factors is possibly a general mechanism involved in intestinal adaptation.
- Published
- 1990
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