Dual energy X-ray absorptiometry precisely and accurately predicts lamb carcass composition at abattoir chain speed across a range of phenotypic and genotypic variables

Dual energy X-ray absorptiometry (DEXA) is an imaging modality that has been used to predict the computed tomography (CT)-determined carcass composition of multiple species, including sheep and pigs, with minimal inaccuracies, using medical grade DEXA scanners. An online DEXA scanner in an Australian abattoir has shown that a high level of precision can be achieved when predicting lamb carcass composition in real time. This study investigated the accuracy of that same online DEXA when predicting fat and lean percentages as determined by CT over a wide range of phenotypic and genotypic variables across 454 lambs over 6 kill groups and contrasted these results against the current Australian industry standard of grade-rule (GR) measurements to grade carcasses. Lamb carcasses were DEXA scanned and then CT scanned to determine CT Fat % and CT Lean %. All phenotypic traits and genotypic information, including Australian Sheep Breeding Values, were recorded for each carcass. Residuals of the DEXA predicted CT Fat % and Lean %, and the actual CT Fat % and Lean % were calculated and tested against all phenotypic and genotypic variables. Excellent overall precision was recorded when predicting CT Fat % (R2 = 0.91, RMSE = 1.19%). Small biases present for sire breed, sire type, dam breed, hot carcass weight and c-site eye muscle area could be explained by a regression paradox; however, biases among kill group (−0.73% to 1.01% for CT Fat %, −1.48% to 0.76% for CT Lean %) and the Merino sire type (0.36% for CT Fat %, −0.73% for CT Lean %) could not be explained by this effect. Over the large range of phenotypic and genotypic variation, there was excellent precision when predicting CT Fat % and CT Lean % by an online DEXA, with only minor biases, showing superiority to the existing Australian standard of GR measurements

Dual energy x-ray absorptiometry predicts lamb carcass composition at abattoir chain speed with high repeatability across varying processing factors

An on-line Dual Energy X-ray Absorptiometry (DXA) scanner was used in an Australian abattoir to predict computed tomography (CT) determined composition % of fat, lean muscle and bone in lamb carcasses at chain speed. This study assessed the effect of spray-chilling on these estimates, as well as their repeatability over a 10-min period, and over a 72 h period. There was no prediction bias between the 15 spray-chilled and 15 non-spray-chilled carcasses. When repeat DEXA scans were undertaken across a 10-min period, there was a high level of repeatability for the prediction of CT Fat %. When repeat scans were conducted at 6 time points across a 72 h period the precision of the DXA prediction of CT Fat % of 30 carcasses remained high (R2 = 0.94, RMSEP = 1.20%), although small biases existed between time points (P < 0.01). These biases were minimised when the DXA scanner had been operational prior to experimentation, suggesting a ‘warm-up’ effect

The Cross-Cultural Knowledge Sharing Challenge: An Investigation of the Co-location Strategy in Software Development Offshoring

Part 4: Software DevelopmentInternational audienceCross-cultural offshoring in software development challenges effective knowledge sharing. While research has suggested temporarily co-locating participants to address this challenge, few studies are available on what knowledge sharing practices emerge over time when co-locating cross-cultural software developers. This paper presents a longitudinal case study of an offshoring project with co-location of Indian and Danish software developers for 10½ months. A community-of-practice (CoP) analysis is offered of what knowledge sharing practices emerge over time and how these where facilitated. The study supports previous studies’ suggestion of co-location in offshoring for helping cross-cultural knowledge sharing. However, the short initial period of co-location suggested in these studies, was insufficient for achieving knowledge sharing practices indicating a CoP. In conjunction with a longer period of co-location four facilitators of cross-cultural knowledge sharing were shared office, shared responsibility for tasks and problems, shared prioritization of team spirit, and a champion of social integration