Use of computer tomography based predictors of meat quality in sheep breeding programmes
Dr Nicola Lambe
am a first year PhD student at SRUC. After gaining an honours degree in
agriculture at SRUC, I then worked as a research technician with SRUC
and in November 2011 started my PhD.
My research interests lie in the development and investigation of in
vivo predictors of meat quality in lamb and the inclusion of potential
predictors in sheep breeding programmes in the UK. Other research
interests include the measurement of meat quality both in vivo and post
mortem and the developments in improving meat quality through animal
breeding strategies and novel processing techniques.
In addition to research I am keen on knowledge transfer and engage
with researchers and industry bodies regarding some of the current
issues in animal breeding and meat quality.
"Use of computer tomography based predictors of meat quality in sheep breeding programmes"
are different ways to improve meat eating quality (MEQ) characteristics
in meat, both in vivo and post mortem, with the degree of intramuscular
fat (IMF) playing an important role. In beef a ‘window of
acceptability’ has been identified, varying between a lower limit of 3%
IMF and an upper limit of 7% for maximum palatability. Consumer
driven preference for leaner meat, coupled with the meat processing
industries preference for a reduction in carcass fat, an increase in
lean meat yield and a reduction in waste, have led to continued intense
selection for lean growth and reduced fatness. However, IMF and carcass
fat are genetically highly positively correlated, so this selection may
have a negative impact on IMF levels, compromising MEQ.
computed tomography (CT) can measure fat, muscle and bone in vivo and CT
predictions of carcass composition have been used in commercial UK
sheep breeding programmes over the last few decades.Previous
research has demonstrated that average muscle density (MD) estimated by
CT is a good predictor of IMF in sheep and other species. Strong
negative correlations were found between IMF and MD. Taste panel scores
for lamb MEQ traits such as flavour, juiciness and overall palatability
were also shown to have strong negative genetic and phenotypic
correlations with CT MD. SAC have, since 2002, had the technology
available to perform spiral CT scanning improving the quality and amount
of detailed images available through CT, in contrast with earlier
techniques which involved taking a ‘slice’ of an area of interest and
then moving on to the next area of interest.
The use of spiral CT,
which is able to capture detailed three-dimensional information, may
allow further advances in predicting aspects of meat quality. CT
provides the means to quantify both IMF and carcass fat in vivo,
enabling these measurements to be exploited in selection programmes.
most suitable way to use this technology in breeding programmes to
include MEQ and MQ traits has not been fully investigated. Genetic
parameters are required to enable these studies, including estimates of
heritability for CT predictor traits for MQ and correlations with other
Address: Animal & Veterinary Sciences, SRUC, Roslin Institute Building, Easter Bush, Midlothian EH25 9RG
Telephone: 0131 651 9293