MEAT AND FAT AREA MEASUREMENTS ON THE SEC TION BETWEEN THE 5TH AND 6TH RIB IN PIGS

On a total of 85 carcarses of boars and castrates of different lines o f a breeding company muscle and fat areas were measured on the section between the 5th and 6th rib and compared with those measured on the s ection between the 13th and 14th rib. With the development of the Fat- O-Meter (FOM) the measurement of the meat-to-fat ratio became redundan t. However, when estimating breeding values it was shown that in sire lines the estimation of a muscle area is necessary to avoid a decrease in muscle area although the meat percentage (FOM) is increased. Since the section at the 13th/14th rib for the measurement of M. long. dors i area results in a depreciation of up to 20 DM per carcase, the prese nt investigation was made to answer the question whether muscle area m easurements on the 5th/6th rib section could replace those made on the 13th/14th rib section. Repeatabilities of area measurements ments on the 5th/6th rib section are high. Both muscle area and meat-to-fat rat io of the 5th/6th rib section show similarly high correlations (single and multiple correlations) with FOM meat percentage as the area of th e M. long. dorsi and the meat-to fat ratio on the 13th/14th rib sectio n. Muscle area measurements on the 5th/6th rib section can replace tho se on the 13th/14th rib section to avoid a reduction in muscle area th ough, simultaneously meat percentage is high. The use of measurements on the 5th/6th rib section reduces performance testing costs. For the total data the sum of the three muscle areas measured on the 5th/6th r ib section shows the highest correlation with the muscle area at the 1 3th/14th rib section. Within sire lines the muscle area of M. long. do rsi shows the highest correlation with the muscle area measured on the 13th/14th rib section.