Comparison of market hog characteristics of pigs selected by feeder pig frame size or current USDA feeder pig grade standards

• Published in: Journal of animal science Vol. 68; no. 8; pp. 2217 - 2221
• Main Authors: Siemens, A.L. (University of Missouri, Columbia), Lipsey, R.J, Hedrick, H.B, Williams, F.L. Jr, Yokley, S.W, Siemens, M.G
• Format: Journal Article
• Language: English
• Published: Savoy, IL Am Soc Animal Sci 01-08-1990; American Society of Animal Science
• Subjects: Animals; Biological and medical sciences; BODY MEASUREMENTS; CARCASS COMPOSITION; CERDO; CLASIFICACION DE PRODUCTOS; CLASSEMENT; COMPOSICION DE LA CANAL; COMPOSITION DE LA CARCASSE; CRECIMIENTO; CROISSANCE; Feeding. Feeding behavior; Fundamental and applied biological sciences. Psychology; GRADING; GROWTH; Male; Meat - standards; MEDICION DEL CUERPO; MENSURATION CORPORELLE; PESO DE LA CANAL; POIDS A L'ABATTAGE; PORCIN; Random Allocation; SLAUGHTER WEIGHT; SWINE; Swine - anatomy & histology; Swine - growth & development; Vertebrates: anatomy and physiology, studies on body, several organs or systems; Weight Gain; Vertebrata; Mammalia; Selection; Artiodactyla; Ungulata; Carcass; Feeding; Pig
• ISSN: 0021-8812; 1525-3163; 0021-8812
• DOI: 10.2527/1990.6882217x

Two feeder pig grading systems were tested. Forty-five barrows were selected using current USDA Feeder Pig Grade Standards (U.S. No. 1, No. 2 and No. 3). Additionally, 45 barrows were selected using three frame sizes (large, medium and small). Pigs were slaughtered at 100, 113.5 of 127 kg live weight. Trimmed four lean cuts were separated into soft tissue, skin and bone. The skinless belly and soft tissue from the four lean cuts were ground separately and analyzed chemically. Data from each grading system were analyzed separately in a 3 X 3 factorial plan. Pigs selected using current USDA grade standards differed (P less than .05) for last rib backfat, 10th rib fat depth, longissimus muscle area, percentage of trimmed four lean cuts and USDA carcass grade. In the frame size system, pigs with large frame size had less last rib backfat, less 10th rib fat depth, longer carcasses, higher percentage of four lean cuts and superior USDA carcass grades than pigs with small frame size did (P less than .05). The Bradley and Schumann test of sensitivity showed that selection by frame size was more sensitive than current USDA grade standards for discriminating feeder pig foreleg length, body depth and ham width. In addition, selection by frame size was more sensitive than current USDA grade standards for discriminating carcass length and carcass radius length. No increase in sensitivity (P greater than .10) was noted for carcass composition or growth traits over the current USDA Feeder Pig Grade Standards.