A comparison of three ultrasonic machines (Danscan, AIDD (NZ) and Body Composition Meter) and subjective fat and conformation scores for predicting chemical composition of live sheep

Bass, J. J.; Woods, Ella; Paulsen, W. D.

doi:10.1017/s0021859600031191

Cited by 17 publications

(8 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Bass et al (1982) found that the Body Composition Meter predicted carcass fat depth with residual s.d.s of 0-67 and 0-98 mm. Correlations between either left or right measurements of the same ram made at different ages were approximately 0-4.…”

Section: Resultsmentioning

confidence: 95%

“…INTRODUCTION SEVERAL studies of relationships between ultrasonic fat-depth measurements and carcass composition of sheep have been reported (Bass, Woods and Paulsen, 1982;Kempster, Arnall, Alliston and Barker, 1982;Nicol and Parratt, 1984;Cameron and Smith, 1985). These studies suggest that use of ultrasonic measurements marginally improves the prediction of carcass composition over the use of live weight alone and infer that prediction of genetic merit would also be improved.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Effects of selection for divergent ultrasonic fat depth in rams on progeny fatness

1988

View full text Add to dashboard Cite

Fat depths of Southdown and Suffolk rams were ultrasonically measured several times prior to 18 months of age. Ultrasonic measurements were regressed on live weight and deviations from this regression were standardized and summed to select rams with high and low fat depth to produce crossbred progeny for slaughter. An average of 3-24 standard deviations separated high and low sires. Progeny were slaughtered at two ages to determine differences in carcass fatness and its development. A significant difference of -0-5 mm fat depth over the loin eye muscle was found between progeny of low and high sires. Progeny from Suffolk high sires had greater tissue depth over the rib and higher kidney fat weight than those from Suffolk low sires but differences were small or reversed in Southdown progeny. Low progeny had significantly less estimated carcass chemical fat than high progeny. Fat depth C increased less in low progeny between early and late slaughter ages. However, no difference in partition of carcass weight gain to fat weight gain was observed between high and low progeny. Differences in fat weight between high and low progeny, as well as between Southdown and Suffolk progeny, appeared to have occurred prior to the earlier slaughter age.

show abstract

Section: Resultsmentioning

confidence: 95%

mentioning

confidence: 99%

Effects of selection for divergent ultrasonic fat depth in rams on progeny fatness

1988

View full text Add to dashboard Cite

show abstract

“…Subsequently, the concept of fat scoring live lambs to predict GR tissue depth was developed and used with liveweight to market young sheep for meat (Kirton et al 1991;Hegarty et al 2006). Initially, fat score assessors 'felt lambs by hand mainly over the backbone and tail stump' (Kirton et al 1991) and were as accurate as ultrasonic machines, which measure fat over the eye muscle (Bass et al 1982; as cited in Kirton et al 1991). However, Kirton et al (1991) reported that while the 'best drafters were able to rank lambs moderately well', 'all drafters underestimated GR values' but more importantly consistently 'overestimated lean carcasses and underestimated fatter carcasses'.…”

Section: Introductionmentioning

confidence: 99%

The merit of condition score and fat score as alternatives to liveweight for managing the nutrition of ewes

Burgel¹,

Oldham²,

Behrendt³

et al. 2011

Anim. Prod. Sci.

View full text Add to dashboard Cite

Abstract. The liveweight profile of Merino ewes is related to the production and profitability of the sheep enterprise, but few producers measure liveweight to manage the nutrition of Merino ewes. In this paper we examine the relationship between changes in liveweight and condition score using data from the Lifetimewool project and compare condition score and fat score as alternative monitoring tools. Analyses of liveweight and condition score data from 15 flocks of Merino ewes representing a range of different genotypes and environments showed that the relationship between change in liveweight and condition score was on average 9.2 kg per unit change in condition score or 0.19 times the standard reference weight of the flock. In two experiments experienced operators were used to estimate the condition score and fat score in over 200 ewes and accredited ultrasound scanners measured the eye muscle and fat depth at the C site in the same ewes. All assessments were repeated several times in random order. Within 24 h of the assessments the sheep were slaughtered at local abattoirs where the tissue depth at the GR site was measured on the hot carcasses. Both condition score and fat score were highly repeatable though subject to operator bias. They were related to each other and to the objective measures of fat and eye muscle depth at the C site. However, 95% of sheep below condition score 2.5 had a tissue depth (muscle and fat) at the GR site 3 mm, by definition equal to fat score 1. As the condition score of ewes on commercial properties often fluctuates between scores 2 and 3, and small changes in condition score within this range can have large effects on welfare and profit, we conclude that condition score is the most appropriate alternative to liveweight for managing the nutritional profile of ewes.

show abstract

“…Clements et al ( 1981) showed that the accuracy of the scanogram was improved by the addition of a body weight (BW) term. Bass et al (1982) suggested that some single probe ultrasonic machines can predict carcass composition of live sheep. Delfa et al ( 1991) live animals or measured on carcass were the best predictors of total carcass muscle and fat in Rasa Aragonesa ewes.…”

Section: Introductionmentioning

confidence: 99%

Ultrasonic estimates of fat thickness and Longissimus dorsi muscle depth for predicting carcass composition of live Aragon lambs

Delfa

Teixeira

González

et al. 1995

Small Ruminant Research

View full text Add to dashboard Cite

Six ultrasonic fat and muscle depth measurements, taken on the left and the right side of the fourth lumbar vertebra and third stemebra of the breast bone, were related to carcass composition to determine the accuracy of these measurements for predicting carcass compositon of live Aragdn lambs (Temasco) . Live weight alone accounted for 21, 19,26, 18 and 47% of total variation of muscle, bone plus remainder, total fat, and subcutaneous and intermuscular fat, respectively. Addition of ultrasonic fat depth measurement on the right side of the lumbar region accounted for a further 18,31,33 and 36% of muscle, bone plus remainder, total carcass fat and subcutaneous fat, respectively. Addition of the same measurement taken on the left side accounted for a further 15% of intermuscular fat. Live weight alone accounted for only 4% of the total variation of kidney and pelvic fat, but the addition of ultrasonic fat depth measurement on breast bone accounted for a further 26% of the variation of this fat depot. The accuracy of prediction of carcass composition on live animals could be improved by the addition of ultrasonic fat measurements.

show abstract

A comparison of three ultrasonic machines (Danscan, AIDD (NZ) and Body Composition Meter) and subjective fat and conformation scores for predicting chemical composition of live sheep

Cited by 17 publications

References 7 publications

Effects of selection for divergent ultrasonic fat depth in rams on progeny fatness

Effects of selection for divergent ultrasonic fat depth in rams on progeny fatness

The merit of condition score and fat score as alternatives to liveweight for managing the nutrition of ewes

Ultrasonic estimates of fat thickness and Longissimus dorsi muscle depth for predicting carcass composition of live Aragon lambs

Contact Info

Product

Resources

About