bluuebunny/crossref_metadata_2025_split huggingface dataset:
Modelling reversible execution of robotic assembly
Authors: Laursen Johan Sund , Ellekilde Lars-Peter , Schultz Ulrik Pagh 
Published: January 2018

SUMMARYProgramming robotic assembly for industrial small-batch production is challenging; hence, it is vital to increase robustness and reduce development effort in order to achieve flexible robotic automation. A human who has made an assembly error will often simply undo the process until the error is undone and then restart the assembly. Conceptually, robots could do the same. This paper introduces a programming model that enables robot assembly programs to be executed in reverse. We investigate the challenges in running robot programs backwards and present a classification of reversibility characteristics. We demonstrate how temporarily switching the direction of program execution can be an efficient error recovery mechanism. Moreover, we demonstrate additional benefits arising from supporting reversibility in an assembly language, such as increased code reuse and automatically derived disassembly sequences. As a default approach to reversibility, we use program inversion and statement-level inversion of commands, but with a novel override option providing alternative sequences for asymmetric reverse actions. To efficiently program for this model, this paper introduces a new domain-specific language, SCP-RASQ (Simple C++ Reversible Assembly SeQuences). In initial experiments, where 200 consecutive assemblies of two industrial cases were performed, 18 of 22 errors were corrected automatically using only the trial-and-error capabilities that come from reverse execution.
Effects of Ensilage and Silage Fermentation Pattern on the Intake and Performance of Lactating Dairy Cows
Authors: Cushnahan A , Mayne C S 
Published: January 2018

It is generally acknowledged that lactating dairy cows offered grass silage consume less dry matter (DM) and produce less milk with a lower protein concentration than cows offered fresh pasture. However, there is little evidence to indicate whether these effects are due to the influence of ensiling per se or to differences in herbage composition. The aims of the current experiment were to evaluate the effects of ensiling per se and silage fermentation pattern on forage intake and dairy cow performance.A perennial ryegrass sward (Lolium perenne cvs Barlenna and Talbot) was divided into 4 areas (A, B, C and D) comprising one area of 6.7 ha (area A) and three areas of 0.7 ha (areas B, C and D). Each area received a total of 361 kg N, 74 kg P2O5 and 144 kg K2O/ha over the season. From 1 June 1993, herbage was harvested once daily from areas B, C and D using a double chop forage harvester and offered to dairy cows housed indoors during weeks 1, 2 and 3 respectively (Treatment G).
Selection for components of efficient lean growth in Large White pigs
Authors: Cameron N.D. 
Published: January 2018

An experiment was started in 1984 at Edinburgh and Wye to study responses to divergent selection for lean growth rate (LGA), lean food conversion ratio (LFC) and daily food intake (DFI). This paper measured the selection pressure applied, the responses in the selection criteria and estimated the genetic and phenotypic relationships between the selection criteria with ad-libitum feeding of Large White pigs after four generations of selection.Selection objectives and criteria. The LGA (LFC) selection objective was to obtain equal correlated responses in growth rate (food conversion ratio) and carcass lean content, measured in phenotypic s.d. The LGA, LFC and DFI selection criteria had phenotypic s.d. of 27, 29 and 250 units and results are presented in s.d. units.
Responses in performance test traits to selection on components of efficient lean growth
Authors: Cameron N.D. , Curran M.K. 
Published: January 2018

This study determined the responses in performance test traits after four generations of divergent selection for lean growth rate (LGA), lean food conversion ratio (LFC) and daily food intake (DFI) in Large White and Landrace pigs.Within each of the three selection groups, there were high and low selection lines with a control line, each consisting of 10 sires and 20 dams, with an average of 3 boars and 3 gilts tested per litter. A total of 3537 Large White and 2642 Landrace pigs were performance tested in Edinburgh and Wye, respectively. The performance test was over a fixed weight range of 30±3 kg to 85±5 kg. All pigs were individually penned, with ad-libitum feeding of a high energy (13.8 MJ DE/kg DM) and high protein (210 g/kg DM crude protein) pelleted ration.Correlated responses in performance test traits to selection on LGA, LFC and DFI were estimated from the mean within-generation selection line breeding values for each trait, determined with the additive genetic and common environmental (co)variances for performance test traits, which were estimated using multivariate derivative-free residual maximum likelihood analyses.
Reproductive performance of pigs selected for components of efficient lean growth
Authors: Kerr J. C. , Cameron N. D. 
Published: January 2018

This study determined the correlated responses in reproductive performance after five generations of divergent selection for components of efficient lean growth rate in Large White pigs.Data were collected from five generations of pigs divergently selected for daily food intake (DFI), lean food conversion (LFC), lean growth rate on ad-libitum feeding (LGA) and lean growth rate on restricted or scale feeding (LGS). In each selection group, there were high, low and control lines, each consisting of 10 boars and 20 gilts. Animals were mated at around 9.5 months of age. Pregnant gilts were fed 2.5 kg daily and farrowed sows up to 3.5 kg twice daily of a 160 g/kg DM crude protein and 132 MJ/kg DM digestible energy ration. Animals were farrowed at 414 (s.d. 19.7) days of age, on average. No cross fostering was practised. Piglets were offered creep feed containing 235 g/kg DM crude protein and 160 MJ/kg DM digestible energy from 14 days and were weaned at an average of 35 (s.d. 3) days. Litter traits were measured on 1220 selected Large White gilts, with 13030 piglet birth weights and 9951 weaning weights.
Preselection of pigs for performance testing
Authors: Grundy B. 
Published: January 2018

An important aspect of animal improvement is the correct identification of those individuals with superior genetic merit. Testing to accurately assess merit, however, can be a costly component of improvement. In the Group Nucleus there is a substantial number of potential offspring to be tested even within a system where the farrowing and testing is practised continuously throughout the year. In order, therefore, to reduce costs it could be beneficial to accurately predict genetic worth prior to test on either mean parental breeding value or a trait expressed early before test.A Group Nucleus population was modelled by stochastic simulation with selection at two stages The model for the trait(s) selected comprised animal, common environment, herd-year-season and error components. A multivariate animal model BLUP routine was used for the evaluation.
Effect of enzyme supplementation on intestinal parameters in the pig
Authors: Inborr J. , Bedford M. , Graham H. 
Published: January 2018

Reducing foregut digesta viscosity is the primary mode of action of feed enzymes in improving performance in broilers fed wheat and barley based diets (Bedford & Classen, 1991, Graham et al, 1992). In pigs, inclusion of appropriate fibre-degrading enzymes can improve the apparent digestion of nutrients in the small intestine (Graham et al, 1988). This has been attributed to both reduced digesta viscosity and an opening up of the feed cell walls enclosing the nutrients. However, the exact mechanism of this effect is unknown. This trial was designed to investigate the influence of enzyme supplementation on gut parameters in the pig.A total of 40 crossbred pigs were weaned at about 9.5 kg and placed into 5 blocks of 8 individual metabolism cages based on litter origin, sex and liveweight. There were 2 treatment replicates per block. The mash diets were based on barley (751 kg/t), soyabean meal (150 kg/t), fish meal (40 kg/t) and soya oil (20 kg/t), with 1 kg/t chromic oxide as a marker. A hulled, low β-glucan (2.9 % of DM; Arra, Finland) and a naked, high β-glucan (5.3 % of DM; Condor, Canada) barley were used, and diets were fed without or with added /3-glucanase. Pigs were fed for 21 days, then sacrificed. Digesta was collected from the stomach, 4 equal lengths of the small intestine, the caecum and 2 equal sections of the colon plus rectum.
Total phenols and protein precipitation assays as indicators of the inhibitory effects of phenols on rumen micro-organisms
Authors: Wood C D , Plumb V E 
Published: January 2018

Phenolics, such as tannins, have been implicated as inhibitors of digestibility. A wide range of assays for measuring phenols have been proposed (reviewed by Hagerman and Butler, 1989) but there is little experimental evidence to indicate which are most appropriate for assessing nutritive value. The objective of this study was to investigate correlations between phenol assays and the effects of phenolics on in vitro fermentation by rumen micro-organisms to identify which assays most reliably indicated the extent of these effects.Extracts were prepared from 12 Bolivian tree leaf samples using 70% aqueous acetone (500mg dried sample extracted with 5 ml solvent) and analysed for total phenols (TP) by the Prussian Blue method (Price and Butler, 1977), protein precipitation activity (PPA) by a radial diffusion technique (Hagerman, 1987) and condensed tannins (CT) by acid butanol (Porter et al, 1986). The samples used are listed in Table 1.
The Ability of Polyethylene Glycol to Enhance the Digestion of Tropical Forage Legumes of Varying Tannin Content
Authors: Longland A.C. , Theodorou M.K. , Listerl S.J. , Morris P. , Gill M. 
Published: January 2018

Condensed tannins have been implicated in reducing the nutritive value of potentially important feedstuffs, largely through reducing protein and fibre digestion. Tannins can mediate their effects directly by binding to the protein or fibre fraction rendering them resistant to digestion, or indirectly by binding with digestive enzymes, preventing their catalytic action. These adverse effects of tannins, however, can be mitigated by the use of agents such as polyethylene glycol (PEG) which form complexes with condensed tannins rendering them less effective as protein and fibre-binding agents. In this study, the effects of polyethylene glycol on (a) the in vitro fermentability and (b) the digestibility of the fibre fraction (= non-starch polysaccharide; NSP) of leaves of six tropical forage legumes varying in condensed tannin content was investigated.The species used, chosen for their varying tannin contents, were Sesbania goetzei (SG), S. seban (SS), Leucaena leucocephala (LL), Dioclea guianensis (DG) Calliandra sp. (C) and Tadehagi sp. (T23).
Use of Fresh or Frozen Cow Faeces Instead of Sheep Rumen Liquor to Provide Mocroorganisms for in Vitro Digestiblity Assays of Forages
Authors: Akhter S , Owen E , Fall A , O'Donovan F , Theodorou M K 
Published: January 2018

Current techniques for in vitro digestion of forages depend on the use of rumen fistulated animals to supply microbial suspensions in rumen liquor. The objective of the present study is to develop a noninvasive alternative to rumen liquor as a source of micro-organisms in the two-stage, in vitro digestion technique of Tilley and Terry (1963).EL Shaer, Omed, Chamberlain and Axford (1987) showed a high correlation between digestibility in vitro determined using micro-organisms from rumen liquor and from freshly-voided sheep faeces. The disadvantages of using sheep faeces are (a) the need for fresh faeces, (b) the small quantities voided at any given time and (c) the difficulty of enticing sheep to defaecate at a specific time.Cow faeces as a source of micro-organisms was investigated in the present study because of the ease of collecting a large quantity of freshly-voided faeces at a given time. Another objective of the present study was to investigate whether faeces could be frozen and stored for future use as a source of micro-organisms for the in vitro digestibility assay. A further objective was to investigate whether rumen liquor could be frozen and stored for future use.
A comparison of whole crop fodder beet atand grass silages when fed to Ewes in late pregnancy
Authors: Whittle C.T. , O'Doherty J.V. , Crosby T.F. 
Published: January 2018

Whole crop fodder beet silage is a highly nutritious feed for both cattle and sheep. It is also considered that the addition of an absorbent further enhances both the feeding value and its palatability. The objective of this experiment was to compare the nutritive value of two types of whole crop fodder beet silage with that of grass silage when fed to ewes in late pregnancy.Twenty two oestrus synchronised, twin bearing, mature ewes (2-7 yrs) of mixed lowland breeds were selected for the trial. They were housed on December 17th, approximately 10 weeks prior to their expected mean lambing date. Following pregnancy scanning, the ewes were allocated to their respective treatment groups. Each of the three treatment groups were balanced for breed, age and live weight. The ewes were individually penned with peat moss as the bedding material.
A comparison of grass silage and whole crop fodder beet Silage when fed to sheep.
Authors: O'Doherty J.V. , Callan J.J. , Quinn P.J. , Crosby T.F. 
Published: January 2018

The use of fodder beet in diets fed to cattle and sheep has always been valued highly. Recent long-term experiments have shown that the palatability and high feeding value of fodder beet is fully preserved during the ensiling process. The objective of this experiment was to compare the nutritive value of whole crop fodder beet silage with that of grass silage when fed to sheep.The grass silage was harvested from a primary growth of perennial ryegrass, which had a dry matter (DM),water soluble carbohydrate and crude protein contents of 191,137, and 53 g/kg DM respectively on 30/31 May following a 12 hour wilt and had 2.5 litres of formic acid applied in the field via the forage harvester. The whole crop fodder beet (var. Amigo, DM 155 g/kg; CP. 65 g/kg DM) was harvested on 30 October using a whole crop harvester. Eight cheviot cross castrated male sheep weighing on average 47 kg were randomly allocated to the two silage treatments, and then housed in metabolism cages fitted with urine and faeces separators. The trial consisted of an initial 10 day acclimatisation period and a further 10 days during which feed intake, faeces and urinary output were recorded.
The effects of ensiling molassed sugar beet pulp with grass and protein supplementation on pregnant ewe performance.
Authors: O'Doherty J.V. , Crosby T.F. , Quinn P.J. 
Published: January 2018

There is increasing interest in the addition of dry feed materials to grass at ensiling, primarily as a means of reducing effluent production although other benefits claimed include improvements in silage fermentation and animal performance. The objective of the present study was to examine the possible use of molassed sugar beet pulp fed either separately or ensiled with grass at the time of silage making on ewe and lamb performance, and with or without protein supplementation.Grass from a primary growth of perennial ryegrass with dry matter, water soluble carbohydrate and crude protein contents of 13.2%, 24 g/kg and 106 g/kg DM respectively was mowed on June 2nd and was picked up using a precision chop harvester on the 4th and 5th of June. The weather during this period was extremely unfavourable for good silage making. There were 7.5, 1.5 and 2.8 mm of rainfall on the 3rd, 4th and 5th of June. The temperatures (0 C) on these days were: 2nd June - 12.9: 3rd -10.6: 4th - 10.7. There was no bright sunshine hours on either the 3rd or 5th of June and only 2.1 hours on June 4th. Two treatments were imposed (i) formic acid (2.5 litres/t) applied in the field via the forage harvester (GS) (ii) molassed sugar beet pulp (MSBP)(50 kg/t) applied by hand in the silo on top of each load of grass(GSP).The two silos were filled .consolidated and sealed within 24 hours.
In Vitro Fermentation of the Non-Starch Polysaccahride Fraction of Tropical Forage Legumes
Authors: Longland A.C. , Pilgrim R.D. , Thorpe J. , Lister S.J. , Morris P. , Theodorou M.K. 
Published: January 2018

The fibre fraction (= non-starch polysaccharides; NSP) of tropical forage legumes is a potentially important source of dietary energy. Such legumes, however often contain tannins which can reduce the fermentability of the NSP fraction. In this study, the monosaccharide composition and in vitro digestibility of the NSP fraction of eleven tropical forage legumes varying in condensed tannin content, were investigated.Milled, lyophilised leaves of 5 species of forage legume from Ethiopia, Sesbania goetzei (SG), Sesbania sesban (SS) Leucaena leucocephala (LL), Acacia cyanophylla (AC), Chamaecytisus palmensis (CP)) and six from Colombia, Calliandra sp. 29400 (C), Dioclea guianensis (DG), Flemingia macrophylla 77409 (FM) Tadehagi sp. 23227 (T23), 13269 (T69) and 13275 (T75)) were used. One gram samples were fermented at 39°C for 7 d under anaerobic conditions in modified Van Soest medium inoculated with bovine rumen fluid (5 replicates per species). At the end of the fermentation period, residues were filtered, washed with distilled water and lyophilised. The NSP content and composition of the original samples and their residues were determined by the method of Englyst and Cummings (1984). The bound, soluble and total condensed tannin contents of the original samples were determined by the method of Terrill et al. (1992).
The use of velocity of ultrasound to monitor body composition in lactating cows
Authors: Cooper A. , Aston K. , Dhanoa M.S. , McAllan A.B. 
Published: January 2018

Previous studies have shown that using non-invasive techniques such as the measurement of the velocity of ultrasound (VOS) through live animals (Sim. 1983) can, in the body of the lactating dairy cow, provide reliable estimates of chemical composition and energy content (Ivings,Gibb,Dhanoa and Fisher.1993). In this study VOS was used to monitor the changes in body composition of dairy cows fed concentrates containing differing levels of crude protein (CP).Fifty-five Holstein-Friesian cows were offered 5kg of fresh concentrate containing 156(L),245(M) or 338(H)g CP/kg dry matter (DM) together with grass silage (162g CP/kg DM,D value 0.723,ME 12.3 MJ/kg DM and pH 3.72) offered ad-libitum over weeks 4 to 21 of lactation. There were five treatments designated LL,LH,MM,HL, HH with a change of CP level where appropriate in week 13. Five cows were selected from each treatment and VOS measurements taken from two sites on the hindquarters (B and Bl) at weeks 12,15,18 and 21. Liveweights were also taken at this time.
Effect of chemical structure of fats upon their apparent digestible energy Value when fed to young pigs.
Authors: Powles J. , Wiseman J , Cole D J A , Hardy B 
Published: January 2018

Previous studies have examined the effect of the degree of saturation (as measured by th3 ratio of unsaturated to saturated fatty acids, U/S) and free fatty acid (FFA) content on the digestible energy (DE) value of fats fed to growing/ finishing pigs. However, there have been no detailed studies with the immediate post-weaning pig, which was the objective of the current programme.Two fats of differing degrees of saturation (U/S) and their respective acid oils of high free fatty acid (FFA) content were obtained for evaluation. Fats were Soyabean Oil (SO), Soyabean Acid Oil (SAO), Tallow (T) and Tallow Acid Oil (TAO).
The effect of liquid feeding in a deep straw system on sow behaviour and welfare
Authors: Baynes P.J. , Hunter E.J. , Guise H.J. , Penny R.H.C. 
Published: January 2018

A survey of dry sow housing across England (Baynes and Hunter, 1993) was conducted to assess farmers' future plans and opinions regarding the onset of the 1999 ban relating to stall and tether housing systems. Results from this survey showed that approximately one third of English pig producers currently with these types of systems were undecided as to which system to choose. A number of case studies are currently being conducted on existing group-housed systems to contribute to a data base on group housing options.Sows were housed in a general purpose barn which had been divided into 12 pens, each housing ten sows. Sows were liquid fed once a day in a common trough with partial barriers. Total space allowance was 2.96m2/sow, of which 1.23m2was kennelled.
The effect of a simple conversion of a tether house on sow welfare
Authors: Baynes P.J. , Hunter E.J. , Guise H.J. , Penny R.H.C. 
Published: January 2018

A survey of dry sow housing across England (Baynes and Hunter, 1993) indicated that 30% of producers currently with confinement systems would like to convert their existing sow buildings to conform with the ban on stall and tether systems in 1999. This study assessed the feasibility of a minimal cost conversion of part of a tether house in which the sows were liquid fed.Sows were housed in a 21 year old tether house capable of housing 152 sows in four rows. The middle section of the house consisted of two rows of tethers, back to back, and part of this was gated off to create two pens, each capable of holding 10 sows in two rows of five. Total space allowance was 14m2/sow. Sows were of mixed weights and parities and all had previous experience of the tether house. Both groups were observed for three hours immediately after mixing, for two hours feeding on the following day, and for two hours on nine subsequent days. Eight categories of agonistic interaction (head swing with mouth closed, head swing with mouth open, push, attempted bite/slash, bite/slash, mount, vulva bite and fight of more than ten seconds), space usage and skin lesions (scored from one to five on eight regions of the body - Stewartet al, 1993) were recorded during each observation period. Sow weight and condition (scored from one to five - Whittemore, 1980) were assessed on entry to the building at four weeks post-weaning and on exit, approximately five days pre-farrowing.
Effect of three lactation housing systems on sow and piglet performance and behaviour
Authors: Hatet G , Edwards S A , Gall K , Arey D S 
Published: January 2018

Confinement of sows in farrowing crates and early weaning of piglets are two major areas of concern in relation to animal welfare in intensive pig production systems. In this project, two alternative lactation systems in which these potential stressors are absent or reduced were evaluated.36 sows and litters were used in an experiment to evaluate, from weekly performance records and observations of behaviour, two alternative strategies for housing and management during lactation in comparison with a conventional current system:
(1)Family system (F): Sows were housed throughout in groups of four with voluntary access farrowing pens. Piglets remained with the sows for 12 weeks and a boar was introduced after 3 weeks to induce oestrus.(2)Multisuckling system (M): Sows farrowed in individual crates but were grouped in fours in straw pens after 2 weeks. Piglets remained with the sows for 12 weeks and a boar was introduced after 3 weeks.(3)Conventional commercial system (C). Sows remained in part-slatted, unbedded farrowing crates throughout a four week lactation. Piglets weaned into flat decks and transfered after four weeks into fully slatted grower pens.