Data/hora: 27/05/2024 06:41:03

Biblioteca(s): | Embrapa Caprinos e Ovinos.
Data corrente: | 31/03/2005
Data da última atualização: | 31/03/2005
Autoria: | JONES, H. E.; LEWIS, R. M.; YOUNG, M. J.; WOLF, B. T.
Título: | The use of X-ray computer tomography for measuring the muscularity of live sheep.
Ano de publicação: | 2002
Fonte/Imprenta: | Animal Science, v. 75, pt 3, p. 387-399, 2002.
Idioma: | Inglês
Conteúdo: | Potential measures of muscularity derived from X-ray computer tomography (CT) were assessed using data for 160 sheep (50 Suffolk males, 50 Suffolk females, 40 Texel males and 20 Charollais males). One-fifth of the lambs within each breed and sex were slaughtered at each of 14, 18 or 22 weeks of age and two-fifths slaughtered at 26 weeks. All lambs were CT scanned prior to slaughter with longitudinal and cross-sectional scans taken at three positions along the body [5th lumbar vertebra (LV5), mid-shaft of the femur (FEM) and ischium (ISC)]. After slaughter, linear measurements of side length (SL) and M. longissimus thoracis et lumborum (LTL) width (A) and depth (B) (12/ 13th thoracic vertebra) were taken on the left side of the carcass. The side was dissected and femur length (FL), the weight of three muscles surrounding the femur M3) and the total muscle weight in the side (TM) were recorded. Five muscularity measures were calculated for the carcass. Two for the LTL muscle (NSL, B/SL), one for the hind leg(vM3/FL3) andonefor the whole carcass(vTM/SL3). Correlations between spine length measured on the CT longitudinal scans and side length measured on the carcass were high (> 0.62), while correlations between measurements of LTL width and depth on the carcass with those on  the LV5 scan were moderate (> 0.41). CT measures of muscularity were derived using linear measurements taken  on CT scans together with a prediction of total muscle weight using CT tissue areas. Correlations between CT measures and dissection measures of LTL and whole carcass muscularity were modera te to high (0.33-0.54). Correlations between the dissection measure and four CT measures of hind leg muscularity were higher (0.48- 0.60). These results clearly show that good in vivo measures of muscularity can be obtained for sheep by using measurements that can be taken on CT scans. This will be a useful tool for selection programmes aiming to improve sheep carcass shape, particularly those already using CT scanning to increase rates of genetic improvement in lean tissue growth.
Palavras-Chave: | Medida.
Thesagro: | Carne; Músculo; Ovino; Tomografia.
Categoria do assunto: | --
Registro original: | Embrapa Caprinos e Ovinos (CNPC)
Exemplares: | CNPC - (17573-1) - ADC - AP - -- -  -  - v.75,n..3 - DIS