Abstract: With a view towards, the genetic improvement of economically important traits, we previously generated a beef cattle F2 resource population from a Japanese Black and Limousin cross. Here, we report on a genome-wide scan for QTLs affecting muscle fiber diameter and composition traits. The longissimus thoraces muscle samples from 150 F2 animals were examined to determine muscle fiber type and diameter. At the same time, F2 animals as well as the F1 parents and F0 grandparents were genotyped for 313 informative micro satellite markers that spanned 2.382 cM of the Bovine autosomes. The results of a genome scan using least-squares regression interval mapping provided evidence for a QTL affecting the diameter of the red muscle fiber (<5% chromosome-wide level) at 42 cM on BTA17; a QTL affecting the composition of the red and white muscle fibers (<5% chromosome-wide level) at 0 cM on BTA5 and a QTL affecting the composition of the red muscle fiber (<5% chromosome-wide level) at 106 cM on BTA8. Thus in this study, we detected 3 QTLs for 3 traits. The detected QTLs were either contiguous with or overlapped previously reported QTLs with effects on several traits assumed to be related to muscle histochemical properties.
Tsuyoshi Abe, Hiroyuki Hasebe, Tetsuo Nakagawa, Yoshinobu Uemoto, Kaoru Saito, Toshihiro Nade, Tadashi Kawamura and Eiji Kobayashi, 2009. Detection of Quantitative Trait Loci Affecting Muscle Histochemical Properties in the F2 Progeny of a Cross Between Japanese Black and Limousin Breed. Journal of Animal and Veterinary Advances, 8: 2190-2195.