Effects of dietary fibre and the provision of a foraging substrate on the welfare of sows in different grouping systems

End of project reportThere are no clear guidelines on how best to meet the EU legislative requirement (Council Directive 2001/88/EC) that pregnant sows and gilts should be provided with sufficient amounts of bulky or high fibre diets and high energy food to satisfy hunger and the motivation to chew. Therefore the aim of this project was to investigate the effect of increasing dietary fibre levels and providing access to a foraging substrate on the welfare of sows housed in dynamic and static groups. To achieve this a review paper was compiled and three experiments were conducted. The aim of the review paper was to assess the effectiveness of increasing dietary fibre levels on the welfare of pregnant sows. Previous research found that increasing dietary fibre levels decrease activity levels and the performance of stereotypic behaviour, and increase resting behaviour. However, high fibre diets do not appear to reduce aggression between group-housed pregnant sows. The research clearly showed that the effectiveness of high fibre diets is influenced by the source of fibre, with soluble fibres being more effective in reducing stereotypic behaviours than insoluble fibres. However the optimum fibrous ingredient, or combination of ingredients, and the optimum dietary inclusion rate for these ingredients remains unclear

Comparative grazing behaviour of lactating suckler cows of contrasting genetic merit and genotype

peer-reviewedThe objective of this study was to determine if differences in grazing behaviour exist between lactating suckler cows diverse in genetic merit for the national Irish Replacement index and of two contrasting genotypes. Data from 103 cows: 41 high and 62 low genetic merit, 43 beef and 60 beef x dairy (BDX) cows were available over a single grazing season in 2015. Milk yield, grass dry matter intake (GDMI), cow live weight (BW) and body condition score (BCS) were recorded during the experimental period, with subsequent measures of production efficiency extrapolated. Grazing behaviour data were recorded twice in conjunction with aforementioned measures, using Institute of Grassland and Environmental Research headset behaviour recorders. The effect of genotype and cow genetic merit during mid- and late-lactation on grazing behaviour phenotypes, milk yield, BW, BCS and GDMI were estimated using linear mixed models. Genetic merit had no significant effect on any production parameters investigated, with the exception that low genetic merit had a greater BCS than high genetic merit cows. Beef cows were heavier, had a greater BCS but produced less milk per day than BDX. The BDX cows produced more milk per 100 kg BW and per unit intake and had greater GDMI, intake per bite and rate of GDMI per 100 kg BW than beef cows. High genetic merit cows spent longer grazing and took more bites per day but had a lower rate of GDMI than low genetic merit cows, with the same trend found when expressed per unit of BW. High genetic merit cows spent longer grazing than low genetic merit cows when expressed on a per unit intake basis. Absolute rumination measures were similar across cow genotype and genetic merit. When expressed per unit BW, BDX cows spent longer ruminating per day compared to beef. However, on a per unit intake basis, beef cows ruminated longer and had more mastications than BDX. Intake per bite and rate of intake was positively correlated with GDMI per 100 kg BW. The current study implies that despite large differences in grazing behaviour between cows diverse in genetic merit, few differences were apparent in terms of production efficiency variables extrapolated. Conversely, differences in absolute grazing and ruminating behaviour measurements did not exist between beef cows of contrasting genotype. However, efficiency parameters investigated illustrate that BDX will subsequently convert herbage intake more efficiently to milk production

RascalC: A Jackknife Approach to Estimating Single and Multi-Tracer Galaxy Covariance Matrices

To make use of clustering statistics from large cosmological surveys, accurate and precise covariance matrices are needed. We present a new code to estimate large scale galaxy two-point correlation function (2PCF) covariances in arbitrary survey geometries that, due to new sampling techniques, runs $\sim 10^4$ times faster than previous codes, computing finely-binned covariance matrices with negligible noise in less than 100 CPU-hours. As in previous works, non-Gaussianity is approximated via a small rescaling of shot-noise in the theoretical model, calibrated by comparing jackknife survey covariances to an associated jackknife model. The flexible code, RascalC, has been publicly released, and automatically takes care of all necessary pre- and post-processing, requiring only a single input dataset (without a prior 2PCF model). Deviations between large scale model covariances from a mock survey and those from a large suite of mocks are found to be be indistinguishable from noise. In addition, the choice of input mock are shown to be irrelevant for desired noise levels below $\sim 10^5$ mocks. Coupled with its generalization to multi-tracer data-sets, this shows the algorithm to be an excellent tool for analysis, reducing the need for large numbers of mock simulations to be computed.Comment: 29 pages, 8 figures. Accepted by MNRAS. Code is available at http://github.com/oliverphilcox/RascalC with documentation at http://rascalc.readthedocs.io

Disentanglement and Decoherence without dissipation at non-zero temperatures

Decoherence is well understood, in contrast to disentanglement. According to common lore, irreversible coupling to a dissipative environment is the mechanism for loss of entanglement. Here, we show that, on the contrary, disentanglement can in fact occur at large enough temperatures $T$ even for vanishingly small dissipation (as we have shown previously for decoherence). However, whereas the effect of $T$ on decoherence increases exponentially with time, the effect of $T$ on disentanglement is constant for all times, reflecting a fundamental difference between the two phenomena. Also, the possibility of disentanglement at a particular $T$ increases with decreasing initial entanglement.Comment: 3 page

Hiding in Plain Sight: Timing and Transparency in the Administrative State

Anecdotal evidence of agencies burying bad news is rife in law and politics. The bureaucracy regularly is accused of announcing controversial policies on holidays and weekends when public attention is elsewhere. We show that this conventional wisdom is wrong, or at least significantly incomplete. The conventional wisdom is riddled with theoretical holes, and there is little systematic empirical evidence to support it. After critiquing the conventional account of agencies hiding bad news, we articulate and defend a revised theory of strategic timing in administrative law. We argue that timing decisions rarely affect the visibility of decisions but can drive up the costs of monitoring and responding for interest groups and legislative coalitions. Agency discretion to choose when to announce policy decisions can even allow agencies to influence which interest groups monitor the regulatory process and therefore whose preferences must be taken into account. We evaluate both the conventional wisdom and our revised theory using twenty-five years of empirical evidence. We then develop the implications for administrative law doctrine and institutional design of the bureaucracy