29 research outputs found
Knowledge Management: A Discovery Process
Getting strategic about how you organize and redistribute knowledge can help just about anyone achieve their goals more efficiently. We at The McKnight Foundation often find ourselves at the center of meaty, data-rich, analytic conversations. This case study summarizes our yearlong exploration and planning to consume, organize, and share knowledge better
Effects of extended grazing during mid, late or throughout pregnancy, and winter shearing of housed ewes, on ewe and lamb performance
peer-reviewedA flock of March-lambing ewes was used to evaluate the effects of (i) extended (deferred, winter) grazing of pasture during mid, late or throughout pregnancy, and (ii) winter shearing of ewes housed during mid and late pregnancy, on lamb birth weight and subsequent growth to weaning. Ewes (n = 265) were allocated at random to five treatments for the period from 7 December (~ day 47 of pregnancy) to lambing. The treatments were: housed shorn (HS), housed unshorn (HU), grazing throughout
(EG), grazing to 20 January followed by housing (EGH), housed to 20 January followed by grazing (HEG). From 1 March to lambing the HEG and EG ewes were dispersed on the paddocks intended for grazing post lambing. All ewes were offered a concentrate supplement during the final 6 weeks of pregnancy. Housed ewes were offered grass silage while ewes on extended grazing were allocated 1.3 kg herbage dry matter per head per day from swards that had been closed for approximately 10 weeks. Ewes plus lambs (except triplet-rearing ewes which were grazed separately) from all treatments were grazed together post lambing, grouped according to lambing date. For treatments HS, HU, EGH, HEG and EG gestation lengths were 147.0, 145.6, 146.3, 146.6 and 146.9 (s.e. 0.34, P < 0.001) days, lamb birth weights were 4.9, 4.3, 4.4, 4.6 and 5.0 (s.e. 0.10, P < 0.001) kg, and lamb weaning weights were 34.6, 32.1, 33.3, 33.8 and 34.9 (s.e. 0.66, P < 0.001) kg, respectively. Extended grazing in mid and late pregnancy resulted in 35% and 65%, respectively, of the increase in lamb birth weight associated with extended grazing throughout. Treatment effects on lamb birth weight were associated with those on weaning weight (P < 0.01, R2 = 0.93). It is concluded that extended grazing or shearing of housed ewes increased lamb birth weight and subsequent weaning weight. The increased lamb birth weight from deferred grazing in mid pregnancy was probably due to improved protein utilisation from the grazed herbage. Meanwhile, the increase
An evaluation of two grassland-based systems of mid-season prime lamb production using prolific ewes of two genotypes
peer-reviewedA 4-year study was undertaken to evaluate the effects of two contrasting management
systems [year-round grazing (YRG) and normal seasonal grazing followed by indoor
feeding during winter (GWF)] on performance of mid-season lambing ewes. On the
GWF system, the annual stocking rate was 14.4 ewes/ha, grass silage was conserved
for winter feeding indoors, and the ewes were lambed indoors and were then turned
out to pasture. The YRG system was stocked at 10.5 ewes/ha, was grazed during the
winter, had outdoor lambing and the animals had access to all the farmlet for summer
grazing. The ewes were Belclare and Cheviot × Belclare which were balanced
across systems. Mean lambing dates and fertiliser N application rates were 20 and 30
March, and 85 and 92 kg/ha, for the GWF and YRG systems, respectively. Concentrate
supplementation during late pregnancy was similar on both systems. For the GWF and
YRG systems, litter size, lamb mortality, number of lambs reared, birth weight (kg),
weaning weight (kg) and lamb carcass output (kg/ha) were 2.17 and 2.24 (s.e. 0.038),
10.1 and 13.8% (P = 0.05), 1.77 and 1.78 (s.e. 0.042), 4.0 and 4.7 (s.e. 0.05, P < 0.001),
27.9 and 30.8 (s.e. 0.25, P < 0.001) and 469 and 348, respectively. Belclare ewes had a
higher litter size (2.34 v 2.07; s.e. 0.038, P < 0.001) and number of lambs reared per
ewe joined (1.86 v 1.69; s.e. 0.048, P < 0.01) than the Cheviot × Belclare ewes. There
were no significant interactions between system and ewe breed type. It is concluded that
the YRG system of prime lamb production was sustainable using prolific ewes but at
a reduced stocking rate (−26%) and with greater lamb mortality relative to the GWF
system. Ewe genotypes with a mean litter size of up to 2.34 lambs are suitable for both
systems. Lamb carcass output of 501 kg/ha was achieved from a primarily grass-based
system of mid-season prime lamb production using prolific ewes (Belclare)
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Grays River Watershed Restoration Status Report 2007, May 1, 2007 - October 30, 2008.
The Bonneville Power Administration (BPA) Project 2003-013-00, 'Grays River Watershed Restoration', began in FY04 and continues into FY09. This status report is intended to summarize accomplishments during the period 1 May 2007 through 30 October 2008. Accomplishments are summarized by Work Elements, as detailed in the Statement of Work (see BPA's project management database PISCES). The Pacific Northwest National Laboratory (PNNL) is collaborating with the Columbia River Estuary Task Force (CREST) on implementation of the Grays River Restoration Project. The Grays River is vitally important to the recovery of Lower Columbia River (LCR) chum salmon because it currently has the most viable population remaining in the LCR region. The Grays River watershed is also important to the recovery of salmon and steelhead in the LCR ecosystem. Today, numbers of naturally spawning salmon and steelhead have declined to levels far below historical numbers because of habitat limiting factors that include but are not limited to the lack of habitat connectivity, diversity, channel stability, riparian function and altered stream flow conditions. The objective of this project is to restore habitat-forming processes to enhance salmon and steelhead populations in the Grays River, following recommendations developed during the FY04-06 BPA-sponsored Grays River Watershed Assessment (BPA Project No. 2003-013-00). Specifically, this project will be the first step in restoring channel structure and function that will increase instream habitat diversity, channel stability, and riparian integrity in the critical response reach upstream and adjacent to critical salmon spawning areas of the Grays River. The major component of this strategy is the planning, design, installation, and monitoring of engineered logjams (ELJ) that will rejuvenate historic channel and floodplain processes. Additional restoration measures include reforesting the riparian corridor to enhance future large woody debris recruitment and investigation of conservation activities within ecologically critical areas. These activities include land acquisition and levee removal to protect critical areas and reconnect floodplain areas. Finally, monitoring integrated with restoration activities is proposed to evaluate restoration effectiveness and allow for adaptive management of future restoration treatments in the project area as well as other degraded watersheds in the Lower Columbia River
Efficient Partitioning of Fragment Shaders for Multiple-Output Hardware
Partitioning fragment shaders into multiple rendering passes is an effective technique for virtualizing shading resource limits in graphics hardware. The Recursive Dominator Split (RDS) algorithm is a polynomial-time algorithm for partitioning fragment shaders for real-time rendering that has been shown to generate efficient partitions
Effects of extended grazing during mid, late or throughout pregnancy, and winter shearing of housed ewes, on ewe and lamb performance
A flock of March-lambing ewes was used to evaluate the effects of (i) extended (deferred, winter) grazing of pasture during mid, late or throughout pregnancy, and (ii) winter shearing of ewes housed during mid and late pregnancy, on lamb birth weight and subsequent growth to weaning. Ewes (n = 265) were allocated at random to five treatments for the period from 7 December (~ day 47 of pregnancy) to lambing. The treatments were: housed shorn (HS), housed unshorn (HU), grazing throughout
(EG), grazing to 20 January followed by housing (EGH), housed to 20 January followed by grazing (HEG). From 1 March to lambing the HEG and EG ewes were dispersed on the paddocks intended for grazing post lambing. All ewes were offered a concentrate supplement during the final 6 weeks of pregnancy. Housed ewes were offered grass silage while ewes on extended grazing were allocated 1.3 kg herbage dry matter per head per day from swards that had been closed for approximately 10 weeks. Ewes plus lambs (except triplet-rearing ewes which were grazed separately) from all treatments were grazed together post lambing, grouped according to lambing date. For treatments HS, HU, EGH, HEG and EG gestation lengths were 147.0, 145.6, 146.3, 146.6 and 146.9 (s.e. 0.34, P < 0.001) days, lamb birth weights were 4.9, 4.3, 4.4, 4.6 and 5.0 (s.e. 0.10, P < 0.001) kg, and lamb weaning weights were 34.6, 32.1, 33.3, 33.8 and 34.9 (s.e. 0.66, P < 0.001) kg, respectively. Extended grazing in mid and late pregnancy resulted in 35% and 65%, respectively, of the increase in lamb birth weight associated with extended grazing throughout. Treatment effects on lamb birth weight were associated with those on weaning weight (P < 0.01, R2 = 0.93). It is concluded that extended grazing or shearing of housed ewes increased lamb birth weight and subsequent weaning weight. The increased lamb birth weight from deferred grazing in mid pregnancy was probably due to improved protein utilisation from the grazed herbage. Meanwhile, the increase
Production and utilization of ensiled forages by beef cattle, dairy cows, pregnant ewes and finishing lambs - a review
This paper reviews the production of, and factors affecting the performance of dairy cows, beef cattle and sheep offered silage based diets in Ireland and UK. Digestibility is the most important factor influencing the feed value of grass silage and consequently animal performance. Each 10 g kg(-1) increase in digestive organic matter in the dry matter (DOMD) increases milk yield of dairy cows by 0.33 kg d(-1), carcass gain of beef cattle by 23.8 g d(-1), carcass gain of finishing lambs by 9.3 g d(-1), lamb birth weight by 52.3 g and ewe weight post lambing by 1.3 kg, respectively. Factors influencing feed value of grass silage are discussed including harvest date, wilting, fertilizer management, chop length and use of additives at ensiling. Maize silage increases the performance of cattle and sheep whilst whole crop wheat silage has no beneficial effect. Advances in silage technology, has enabled the ensiling high protein forages, such as red clover, lucerne and kale