102 research outputs found
Efficacy of Intra-Operative Topical Wound Anaesthesia to Mitigate Piglet Castration Pain—A Large, Multi-Centred Field Trial
No full textPiglet castration results in acute pain and stress to the animal. There is a critical need for effective on-farm methods of pain mitigation. Local anaesthesia using Tri-Solfen® (Animal Ethics Pty Ltd., Melbourne, Australia), a topical local anaesthetic and antiseptic formulation instilled to the wound during surgery, is a newly evolving on-farm method to mitigate castration pain. To investigate the efficacy of Tri-Solfen®, instilled to the wound during the procedure, to alleviate subsequent castration-related pain in neonatal piglets, we performed a large, negatively controlled, randomised field trial in two commercial pig farms in Europe. Piglets (173) were enrolled and randomised to undergo castration with or without Tri-Solfen®, instilled to the wound immedi- ately following skin incision. A 30 s wait period was then observed prior to completing castration. Efficacy was investigated by measuring pain-induced motor and vocal responses during the sub- sequent procedure and post-operative pain-related behaviour in treated versus untreated piglets. There was a significant reduction in nociceptive motor and vocal response during castration and in the post-operative pain-related behaviour response in Tri-Solfen®-treated compared to untreated piglets, in the first 30 min following castration. Although not addressing pain of skin incision, Tri- Solfen® is effective to mitigate subsequent acute castration-related pain in piglets under commercial production conditions
Optimal Methods of Documenting Analgesic Efficacy in Neonatal Piglets Undergoing Castration
No full textAnalgesic products for piglet castration are critically needed. This requires extensive animal experimentation such as to meet regulatory-required proof of efficacy. At present, there are no validated methods of assessing pain in neonatal piglets. This poses challenges for investigators to optimize trial design and to meet ethical obligations to minimize the number of animals needed. Pain in neonatal piglets may be subtle, transient, and/or variably expressed and, in the absence of validated methods, investigators must rely on using a range of biochemical, physiological and behavioural variables, many of which appear to have very low (or unknown) sensitivity or specificity for documenting pain, or pain-relieving effects. A previous systematic review of this subject was hampered by the high degree of variability in the literature base both in terms of methods used to assess pain and pain mitigation, as well as in outcomes reported. In this setting we provide a narrative review to assist in determining the optimal methods currently available to detect piglet pain during castration and methods to mitigate castration-induced pain. In overview, the optimal outcome variables identified are nociceptive motor and vocal response scores during castration and quantitative sensory-threshold response testing and pain-associated behaviour scores following castration
From earthquakes to island area: multi‐scale effects upon local diversity
No full textTropical forests occupy small coral atolls to the vast Amazon basin. They occur across bioregions with different geological and climatic history. Differences in area and bioregional history shape species immigration, extinction and diversification. How this effects local diversity is unclear. The Indonesian archipelago hosts thousands of tree species whose coexistence should depend upon these factors. Using a novel dataset of 215 Indonesian forest plots, across fifteen islands ranging in area from 120 to 785 000 km
2
, we apply Gaussian mixed effects models to examine the simultaneous effects of environment, earthquake proximity, island area and bioregion upon tree diversity for trees ≥ 10 cm diameter at breast height. We find that tree diversity declines with precipitation seasonality and increases with island area. Accounting for the effects of environment and island area we show that the westernmost bioregion Sunda has greater local diversity than Wallacea, which in turn has greater local diversity than easternmost Sahul. However, when the model includes geological activity (here proximity to major earthquakes), bioregion differences are reduced. Overall, results indicate that multi‐scale, current and historic effects dictate tree diversity. These multi‐scale drivers should not be ignored when studying biodiversity gradients and their impacts upon ecosystem function
Observations on the salmon fisheries of Ulster : urging their claims to legislative protection
No full textOptimum Split Trees
No full textA split tree is a special kind of a binary search tree introduced by Sheil [S]. He conjectured that constructing an optimum split tree is an intractable problem since there is a difficulty in applying the dynamic programming technique. We realize that the difficulty arise since top down decisions are required while applying the bottom up dynamic programming technique. We demonstrate that it is possible in this case to overcome such a difficulty, and present a polynomial algorithm for constructing an optimum split tree, This algorithm incorporates top down decisions into a dynamic programming procedure similar to Knuth's EK21 algorithm for constructing an optimum binary search tree. An improved algorithm of complexity O(n 4 ) is finally presented. A modification for the case that equiprobable keys are permitted is discussed.Technical report DCS-TR-12
Sheep Updates 2008 - part 2
No full textThis session covers eleven papers from different authors: The Sheep Room 1. Analgesia for Surgical Husbandry Procedures in Sheep and Other Livestock, Dr Meredith L. Sheil, Animal Ethics Pty Ltd, Associate Sydney University Faculty of Veterinary Science The Wool Enterprise 2. Unmulsed sheep - implications for chemical use, Di Evans & Brown Besier, Department of Agriculture and Food WA 3. Are Damara and Dorper sheep better adapted than Merinos to nutritional stress? - Growth rates, Tim Scanlon1, Andre Martinho de Almeida2, Johan Greeff1, Tanya Kilminster1, John Milton3, Chris Oldham1, Department of Agriculture and Food WA1, Instituto de Investigacao Cientifica Tropical, Lisbon, Portugal2, University of Western Australia3 4. Are Damara and Dorper sheep better adapted than Merinos to nutritional stress? - Carcass attributes, Tanya Kilminster1, Andre Martinho de Almeida2, Johan Greeff1, John Milton3, Chris Oldham1, Tim Scanlon1, Department of Agriculture and Food WA1, Instituto de Investigacao Cientifica Tropical, Lisbon, Portugal2, University of Western Australia3 The Beef Room 5. Benefits of matching animal requirements with pasture feed supply and animal supply market requirements, B.L. McIntyre, Department of Agriculture and Food Western Australia, 6. Optimal grazing for beef, Alison Wheatley, Beef farmer Winnejup, John Lucey, Department of Agriculture and Food, Western Australia 7. Grain Introduction in commercial cattle feedlots, Fiona Jones1,2, Nick Costa2, 1 Department of Agriculture and Food WA and 2 Murdoch University. Mixed Systems 8. Confinement feeding stock in mixed enterprises, John Milton, The University of Western Australia & Independent Lab Services The Sheep Enterprise 9. Making More than Sheep, Ed Riggall, Australian Wool Innovation and Meat & Livestock Australia 10. Sheep Cost of Production - the enemy is at the gate!, JRL (Bob) Hall, JRL Hall & Co 11. Australian lamb - high yielding good to eat, Robin Jacob1, Dave Pethick2, Dave Hopkins3 and Graham Gardner2, 1Department of Agrcultre and Food WA, 2Murdoch University, 3NSW Department of Primary Industrie
Sheep Updates 2008 - part 2
No full textThis session covers eleven papers from different authors: The Sheep Room 1. Analgesia for Surgical Husbandry Procedures in Sheep and Other Livestock, Dr Meredith L. Sheil, Animal Ethics Pty Ltd, Associate Sydney University Faculty of Veterinary Science The Wool Enterprise 2. Unmulsed sheep - implications for chemical use, Di Evans & Brown Besier, Department of Agriculture and Food WA 3. Are Damara and Dorper sheep better adapted than Merinos to nutritional stress? - Growth rates, Tim Scanlon1, Andre Martinho de Almeida2, Johan Greeff1, Tanya Kilminster1, John Milton3, Chris Oldham1, Department of Agriculture and Food WA1, Instituto de Investigacao Cientifica Tropical, Lisbon, Portugal2, University of Western Australia3 4. Are Damara and Dorper sheep better adapted than Merinos to nutritional stress? - Carcass attributes, Tanya Kilminster1, Andre Martinho de Almeida2, Johan Greeff1, John Milton3, Chris Oldham1, Tim Scanlon1, Department of Agriculture and Food WA1, Instituto de Investigacao Cientifica Tropical, Lisbon, Portugal2, University of Western Australia3 The Beef Room 5. Benefits of matching animal requirements with pasture feed supply and animal supply market requirements, B.L. McIntyre, Department of Agriculture and Food Western Australia, 6. Optimal grazing for beef, Alison Wheatley, Beef farmer Winnejup, John Lucey, Department of Agriculture and Food, Western Australia 7. Grain Introduction in commercial cattle feedlots, Fiona Jones1,2, Nick Costa2, 1 Department of Agriculture and Food WA and 2 Murdoch University. Mixed Systems 8. Confinement feeding stock in mixed enterprises, John Milton, The University of Western Australia & Independent Lab Services The Sheep Enterprise 9. Making More than Sheep, Ed Riggall, Australian Wool Innovation and Meat & Livestock Australia 10. Sheep Cost of Production - the enemy is at the gate!, JRL (Bob) Hall, JRL Hall & Co 11. Australian lamb - high yielding good to eat, Robin Jacob1, Dave Pethick2, Dave Hopkins3 and Graham Gardner2, 1Department of Agrcultre and Food WA, 2Murdoch University, 3NSW Department of Primary Industrie
Observations on the salmon fisheries of Ulster : urging their claims to legislative protection
No full textNumerical and analytical modelling of friction pile group settlement performance in clay
No full textOver the past couple of decades, the focus of foundation design has shifted from ultimate
limit state to serviceability limit state, particularly where ground conditions are challenging. Nowadays, the serviceability of a deep foundation system can be considered using advanced constitutive laws within computational software packages that are capable of considering the foundation system as a continuum. However, these methods can become both computationally-intensive and time-consuming if non-linear pile-soil-pile interaction and large groups with non-standard geometries are to be modelled. Simplified methods, generally empirical in nature, can be used in preliminary foundation design, alleviating the computational effort associated with more rigorous analyses. However, some of the assumptions therein are over-simplified. The goal of this thesis is to develop new simplified methods which are relatively easy to implement, yet founded where necessary in parametric studies using rigorous continuum analyses. Both absolute and differential settlement performance of pile groups are considered using PLAXIS 2-D and PLAXIS 3-D Foundation finite element software packages and primarily the Hardening Soil and MIT-S1 constitutive models. Previous empirical solutions from linear elastic work had identified a significant dependence of stiffness efficiency on pile group size and group spacing. In this study, the effect of the pile length-to-diameter ratio, the compressibility of a stiff bearing stratum beneath the pile group and the depth below ground level to the stiff bearing stratum are also considered as variables. As a first stage of this thesis, a set of empirical equations has been formulated which has been shown to predict the stiffness efficiency of pile groups in a database very
well.
For the purpose of developing a more comprehensive semi-empirical solution (analytical in large parts), the load transfer (t-z) method is employed to describe the nonlinear behaviour of a single pile. The Interaction Factor Method (IFM) was then used to extend this analysis to
pile groups. A number of important features associated with single pile and pile group
behaviour were included herein that have not been considered in previous studies:
(i) Pile-to-pile interaction effects were considered within a non-linear framework. In the
course of this exercise, the author distinguishes between alternative definitions of interaction factor and shows that settlement predictions using IFM match continuum analyses very
closely for friction piles and reasonably well for end-bearing piles.
(ii) A numerical study on single pile and pile group installation effects was undertaken using advanced constitutive models. A variation on the traditional cavity expansion method (CEM)
was adopted for the analysis of single pile effects while group effects were investigated using a new method based on volumetric expansion of tunnels in PLAXIS 2-D; these effects were subsequently incorporated into the analytical approach by means of a simplified model.
(iii) In addition, the reinforcing effects of additional group piles on the soil continuum and
pre-failure pile-soil slip has also been taken into account; this is the first study to include
these effects in a nonlinear analytical approach.
On the subject of differential settlement, an extensive numerical study of the angular
distortion of piled foundations, which has been documented as the most influential
settlement characteristic in the cracking of buildings, has also been undertaken and
formulated into a set of fully-normalised trends. A consistent trend between angular distortion and stiffness efficiency for
corresponding pile cap rigidities was evident. The aforementioned simplified finite element-based
approach was developed using a similar framework and is thus a compatible way to
estimate angular distortion for the group.
Through comparisons with previously published field test data and measurements from
buildings in addition to numerical simulations, the results presented in this thesis indicate that
the proposed approaches provide a viable framework for the serviceability design of pile
groups while alleviating the computational effort and expense associated with rigorous
continuum analyses
- …
