The content of intramuscular fat (IMF%) in lamb is an important trait for the lamb meat value chain. Not only is IMF% an important energy reserve for replacement stock, IMF% is an important driver of lamb meat eating quality. A growing body of research shows an antagonistic relationship between muscle growth traits and fat content across the lamb carcass (including IMF%). The New Zealand sheep industry has selected for muscle growth traits for decades to improve production efficiency and reduce extremes of carcass fatness historically observed, but the impacts on IMF% levels in New Zealand lamb has not been widely investigated.
This paper aims to stimulate discussion on lamb IMF% by reporting on levels of IMF% observed in the M. longissimus lumborum (LL) of 1,705 progeny test lambs raised under extensive, pasture-based production systems across New Zealand, and investigates the relationship between IMF% and Carcass weight, VIAscan®-predicted GR (VSGR) and lean meat yield percentage (VSYLD).
The average IMF% was 2.69%, (SD = 0.83%, and ranged between 0.91-6.42%). IMF% is positively correlated with carcass weight and VSGR and negatively correlated with VSYLD. Considerable variation exists in lamb IMF% highlighting the opportunity to manage IMF% through genetic improvement and optimised on-farm management.
History
Rights statement
This work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.
Language
English
Does this contain Māori information or data?
No
Publisher
New Zealand Society of Animal Production (NZSAP)
Journal title
New Zealand Society of Animal Production
ISSN
1176-5283
Citation
Craigie, C. R., Agnew, M. P., Stuart, A. D., Shorten, P. R., Reis, M. M., Taukiri, K. R., & Johnson, P. L. (2017). Intramuscular fat content of New Zealand lamb M. longissimus lumborum. New Zealand Society of Animal Production, 77, 189–193.