ABSTRACT
Differences in carcass composition, cutability, economic value of the carcass and distribution of certain muscle groups, between bulls with secondary sexual characteristics (bulls(+)), those without (bulls(-)), and steers were investigated. Two carcass mass groups (250-300 and 301-350 kg) were compared. Five carcasses of either mass group were studied within each sex condition group. Bulls(+) had a higher meat percentage (P < 0·05) than bulls(-) or steers. They also had a lower bone percentage than steers (P < 0·05), but non-significant differences were found between bulls(+) and bulls(-) for bone percentage. Significant differences (P < 0·05) between sex condition groups were found for percentages of hindquarter, as well as for distribution of high-priced cuts. Steers had the most favourable distribution and bulls(+) the least favourable. Bulls(-) were intermediate. Masculinity significantly (P < 0·05) influenced the distribution of the chuck, neck, brisket and hind shin cuts, whilst mass had a significant effect on the percentage hind shin and percentage thin flank. It was found that the M. rhomboideus was the only muscle of those studied that was significantly affected by masculinity and it was concluded that this muscle could be used as an indicator of the masculinity of the carcass. The economic values of the carcasses of steers, bulls without secondary sexual development and bulls with secondary sexual development differed non-significantly.
ABSTRACT
Differences in meat quality traits between bulls with secondary sexual development (bulls(+), n = 10), those without this development (bulls(-), n = 10) and steers (n = 10) were investigated. All animals had no permanent incisors (A-age group). Significant differences (P < 0·05) between bulls(+) and bulls(-) were found for the cooking loss percentage of the M. splenius (27·83% versus 31·11%, respectively), iron content of the M. splenius (56·02µg/g versus 49·43µg/g, respectively) and total collagen content of the M. splenius (3·74 versus 4·73 measured as Hyp N/Tot N x 1000, respectively). Drip loss of the wingrib cut (4·01% versus 5·18%, respectively) was also significantly different between bulls(+) and bulls(-). For the M. longissimus thoracis, no significant (P < 0·05) differences in any of the quality-indicating parameters investigated could be found. It is concluded that the M. splenius can be used as an indicator muscle for masculinity, based on meat quality attributes. This is supported by the correlation coefficients obtained between masculinity and the intramuscular collagen content of the M. splenius (r = -0·55) and the iron content of the M. splenius (r = 0·46). For all the other quality attributes investigated, non-significant (P > 0·05) differences between the three sex condition groups were found. It is concluded that the influence of masculinity on meat quality traits of young bulls is of little practical importance in a classification and grading system.
