An evaluation of three ultrasonic machines for predicting the body composition of live pigs of the same breed, sex and live weight

Abstract

Measurements of the m. longissimus and overlying fat at the last rib were taken on 39 live entire male pigs using three ultrasonic machines of differing complexity: Sonatest (simple A-mode machine), Scanogram (modified linear scanner) and Danscanner (‘real time’ scanner). Each machine had a different operator and interpreter. The pigs were from two lines of Large White, one selected for efficiency of lean-tissue gain (20 pigs) and the other a genetic control line (19 pigs). They were measured in the week prior to slaughter at approximately 90 kg live weight (91·4 (s.e. 4·4) kg).The analysis was pooled within line and the precision of carcass lean prediction at constant live weight examined for the three machines. Standard deviation of lean in carcass at equal live weight was 16·2 g/kg.A single fat thickness measurement taken by the Sonatest gave the most precise prediction (residual s.d. = 12·9 g/kg). Marginally poorer relationships were recorded for a similar measurement taken by the Scanogram (13·5 g/kg) and Danscanner (13·3 g/kg). Precision was not improved from the use of additional fat thickness measurements or, in the case of the scanning machines, from the addition of fat area over the m. longissimus or the area of the muscle itself. The results confirm that the Scanogram and Danscanner do not offer significant advantages over the simpler and cheaper Sonatest in the circumstances considered.

Looking under the hide of animals. The history of ultrasound to assess carcass composition and meat quality in farm animals

“…Scanogram were performed. These studies were performed on sheep 54 , cattle 55 and swine 56,57 . In general, the results proved to be favorable to Danscanner in estimating carcass equivalent measurements and repeatability with results very close to those obtained with the Scanogram.…”

Prediction of carcass lean content by real-time ultrasound in Pietrain and negative stress Pietrain

“…of 0·58 (1·72) and 0·65 (1·52) ; adding muscle area to LS-1000 measurements did not further improve R 2 values (Sather et al, 1996). Alliston et al (1982) evaluated two early designs of ultrasound scanning equipment and concluded that including longissimus muscle area measurements with live weight and P2 backfat thickness at the last rib did not improve the precision of estimating carcass lean content. On the other hand, the findings of Molenaar et al (cited by Cisneros et al (1996)) indicated that the accuracy of proportion of lean cuts predicted from real-time ultrasonic scans was significantly improved by including longissimus muscle measurements (depth or area) together with backfat thickness in prediction equations.…”

Effects of feeding level, protein level, and sex of pig on carcass fatness measured by dissection and optical probe methods

“…A study of breeds of extreme type and fatness would indicate whether measuring back fat thickness of pigs using the Intrascope (Kempster & Evans 1979), or any other method (Adam et al 1982;Alliston et al 1982;Kempster et al 1982), is suitable for comparing fatness betweeen commercial breeds.…”