Analysis of the Management and Costs Associated with Rearing Pregnant Dairy Heifers in the UK from Conception to Calving

Good management of the pregnant heifer is crucial to ensure that she is well grown and healthy and calves down easily before joining the milking herd. This study collected primary data on all aspects of heifer management on 101 UK farms during heifer pregnancy from conception to calving including farm factors and associated costs of system inputs. A cost analysis workbook was developed to calculate the cost of rearing per heifer for each of the study farms. Associations between cost of rearing and farms factors were determined using linear regression and analysis of variance. Heifers had a mean age of conception of 509 d (range 365 - 700 d) and an age at first calving of 784 d (range 639 - 973 d). The mean total cost of rearing during pregnancy was £450.36 (range £153.11 to £784.00) with a mean daily cost of £1.64 (range £0.56 to £2.86). The inputs contributing the most to cost were feed (32.7%), labour (23.8%) and slurry disposal (11.2%). Total purchased and homegrown feed and grazing contributed between 25.5% and 65.4% of total costs with a mean contribution of 43.6%. The cost of rearing was lowest in spring calving herds and highest in all year round calving herds with intermediate values in autumn and multi block calving herds. The main variables influencing the cost were the number of days spent at grass, age at first calving, calving pattern, breed, herd size and region. Each extra day in age at first calving increased the mean cost of rearing during pregnancy by £0.33/d whereas every extra day at grass reduced the cost by £1.75/d

A Study of Dairy Heifer Rearing Practices from Birth to Weaning and Their Associated Costs on UK Dairy Farms

There are many inputs into the dairy replacement herd which impact not only on the cost of rearing heifers from birth to first calving, but also on their future longevity and production potential. This study determined the current cost of rearing dairy heifers in the UK through the calculation and analysis of individual costs on a subset of 102 UK dairy farms. Each farm was visited and an extensive heifer rearing questionnaire was completed. Current heifer rearing practices were recorded to provide insight into critical management decisions. A cost analysis workbook was developed to calculate the costs of inputs in the pre-weaning period for labour, calving, feed, housing, health treatments and vaccinations, waste storage, machinery and equipment, and utilities. The average age at weaning was 62 d. The mean cost of rearing from birth to weaning was £195.19 per heifer with a mean daily cost of £3.14 (excluding the opportunity cost of the calf). This ranged from £1.68 to £6.11 among farms, reflecting major differences in management strategies and efficiency. The highest contribution to total costs came from feed (colostrum, milk, starter and forage) at 48.5% with milk feeding making up the greatest proportion of this at 37.3%. The next major expenses were bedding and labour, contributing 12.3% and 11.2% respectively. Unsurprisingly, delaying age at weaning increased total cost by £3.53 per day. Total costs were on average 45% higher on organic farms than conventional due to higher feed costs and later weaning. Calving pattern also had a strong association with the total cost being lowest with spring calving, intermediate with autumn calving and highest in multi block and all year round calving herds.fals

The management and associated costs of rearing heifers on UK dairy farms from weaning to conception

Dairy heifers only start to produce a return on investment at first calving. The length of the nonproductive rearing period is largely governed by farmer decisions on plane of nutrition and reproduction management. Primary data were collected from 101 dairy farms and a cost analysis workbook developed to calculate individual inputs in each of three periods to determine which management decisions and farm factors have the greatest influence on the total costs associated with rearing. This paper covers weaning until conception. Heifers were weaned at 62 d (range 42 - 112 d) and conceived by 509 d (range 365 - 700 d) giving an average weaning to conception period of 447 ± 60 d (range 253 to 630 d). The mean daily cost of rearing during this period was £1.65 (range £0.75 to £2.97 on different farms) giving a mean total cost of £745.94 per heifer (range £295.32 to £1745.85). This large variation was mostly due to the duration, which was mainly determined by age at first breeding (mean 476 days, range 365 - 700 d). The main contributors to total costs were feed (35.6%), labour (24.7%) and bedding (8.9%). The variables most strongly associated with the total costs were age at conception, calving pattern and breed. A multivariable model predicted an increase in mean cost of £2.26 for each extra day in age at conception. The total cost was highest in herds with all year round calving, intermediate in multi-block and lowest in spring and autumn calving herds, with Friesian x and Jersey herds having the lowest cost of rearing.falsePublished onlin

The role of science in physical natural hazard assessment : report to the UK Government by the Natural Hazard Working Group

Following the tragic Asian tsunami on 26 December 2004, the Prime Minister asked the Government’s Chief Scientific Adviser, Sir David King, to convene a group of experts (the Natural Hazard Working Group) to advise on the mechanisms that could and should be established for the detection and early warning of global physical natural hazards. 2. The Group was asked to examine physical hazards which have high global or regional impact and for which an appropriate early warning system could be put in place. It was also asked to consider the global natural hazard frameworks currently in place and under development and their effectiveness in using scientific evidence; to consider whether there is an existing appropriate international body to pull together the international science community to advise governments on the systems that need to be put in place, and to advise on research needed to fill current gaps in knowledge. The Group was asked to make recommendations on whether a new body was needed, or whether other arrangements would be more effective

Soft-bed experiments beneath Engabreen, Norway: regelation infiltration, basal slip and bed deformation

To avoid some of the limitations of studying soft-bed processes through boreholes, a prism of simulated till (1.8 m × 1.6 m × 0.45 m) with extensive instrumentation was constructed in a trough blasted in the rock bed of Engabreen, a temperate glacier in Norway. Tunnels there provide access to the bed beneath 213 m of ice. Pore-water pressure was regulated in the prism by pumping water to it. During experiments lasting 7–12 days, the glacier regelated downward into the prism to depths of 50– 80 mm, accreting ice-infiltrated till at rates predicted by theory. During periods of sustained high pore water pressure (70–100% of overburden), ice commonly slipped over the prism, due to a water layer at the prism surface. Deformation of the prism was activated when this layer thinned to a sub-millimeter thickness. Shear strain in the till was pervasive and decreased with depth. A model of slip by ploughing of ice-infiltrated till across the prism surface accounts for the slip that occurred when effective pressure was sufficiently low or high. Slip at low effective pressures resulted from water-layer thickening that increased non-linearly with decreasing effective pressure. If sufficiently widespread, such slip over soft glacier beds, which involves no viscous deformation resistance, may instigate abrupt increases in glacier velocity

Finite lifetime eigenfunctions of coupled systems of harmonic oscillators

We find a Hermite-type basis for which the eigenvalue problem associated to the operator $H_{A,B}:=B(-\partial_x^2)+Ax^2$ acting on $L^2({\bf R};{\bf C}^2)$ becomes a three-terms recurrence. Here $A$ and $B$ are two constant positive definite matrices with no other restriction. Our main result provides an explicit characterization of the eigenvectors of $H_{A,B}$ that lie in the span of the first four elements of this basis when $AB\not= BA$.Comment: 11 pages, 1 figure. Some typos where corrected in this new versio

Extraction efficiency of drifting electrons in a two-phase xenon time projection chamber

We present a measurement of the extraction efficiency of quasi-free electrons from the liquid into the gas phase in a two-phase xenon time-projection chamber. The measurements span a range of electric fields from 2.4 to 7.1 kV/cm in the liquid xenon, corresponding to 4.5 to 13.1 kV/cm in the gaseous xenon. Extraction efficiency continues to increase at the highest extraction fields, implying that additional charge signal may be attained in two-phase xenon detectors through careful high-voltage engineering of the gate-anode region

Lie discrete symmetries of lattice equations

We extend two of the methods previously introduced to find discrete symmetries of differential equations to the case of difference and differential-difference equations. As an example of the application of the methods, we construct the discrete symmetries of the discrete Painlev\'e I equation and of the Toda lattice equation