Origin assignment by multi-element stable isotopes of lamb tissues.

The carbon, nitrogen and hydrogen isotopic compositions in lamb meat and wool samples under two feeding regimes from five different regions of China were determined by IRMS, which is to investigate their potential for assigning the lamb meat according to geographical origins. The δ(13)C, δ(15)N and δ(2)H values in lamb tissues had significant differences among different regions, with the δ(13)C value is highly related to that of the lamb feeds (p<0.01) and the δ(2)H value is significantly correlated with lamb drinking water (p<0.05). Moreover, δ(13)C, δ(15)N and δ(2)H values of lamb muscle are all highly correlated with the wool samples. A total correct classification of 88.9% and 83.8% were obtained from the combination of C, N and H isotopes of lamb muscle and wool, respectively. These results demonstrate that multi-element isotopes are effective in identifying the geographical origin of lamb meat. Moreover, both muscle and hair tissue can be used for lamb traceability.