CaracterÃsticas comparativas ultrassonogrÃficas in vivo e da carcaÃa de cordeiros e cabritos mestiÃos terminados em confinamento

• Autor(a) principal: Mario Sergio Feitosa Abe
• Data de Publicação: 2012
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Biblioteca Digital de Teses e Dissertações da UFC
• Texto Completo: http://www.teses.ufc.br/tde_busca/arquivo.php?codArquivo=10682
• topic: ovino; caprino; ultrassom; sheep; goat; ultrasound; ZOOTECNIA

The objective was to evaluate the quantitative characteristics of longissimus muscle area (LMA) and subcutaneous fat thickness (SFT) in vivo and in carcass of lambs and kids finished at feedlot. Before slaughter, were measured between the 12th and 13th thoracic vertebrae, with the use of ultrasound, the subcutaneous fat thickness (USFT) and longissimus muscle area (ULMA). Measures on the carcass of the longissimus muscle area (CLMA) and subcutaneous fat thickness (CSFT) were made using a millimeter ruler and pachymeter, respectively. In kids the measures in vivo and in carcass were made over the 3rd and 4th sternebrae and in the sternocostal cartilage between the 3rd and 4th sternebrae. Were used 20 crossbred lambs and 20 crossbred kids, non-castrated, being 10 Â Dorper x Santa InÃs (DxSI) lambs, 10 Â Dorper x Brazilian Somali (DxBS) lambs, 10 Â Savana x Without Defined Standard Breed (SxWDSB) kids and 10 Â Anglo-Nubian x Without Defined Standard Breed (AxWDSB) kids. The DxSI lambs were slaughtered at an average of 138 days of age with average weight of 43.7 kg whereas DxBS lambs were slaughtered with 32.0 kg at an 117 days of age, when both genetic groups reached approximately 3 mm of ultrasound subcutaneous fat thickness. The kids were slaughtered at an average of 197 days of age and body weight of 21.7 kg and 20.3 kg, for SxWDSB and AxWDSB genotypes, respectively. The data were analyzed under a completely randomized design with 4 genotypes and 10 repetitions each. The ULMA and CLMA were higher in lambs than in kids, being DxSI lambs (ULMA = 17.10cmÂ; CLMA = 17.78cmÂ) superior in relation to DxBS lambs (ULMA = 13.51 cmÂ; CLMA = 13. 91cmÂ), while in the kids the values were similar: SxWDSB (ULMA = 6.73 cmÂ; CLMA = 7.65 cmÂ) and AxWDSB (ULMA = 6.72 cmÂ; CLMA = 7.01 cmÂ). There were significant and positive correlations for ULMA and CLMA of lambs (0.75) and kids (0.86). Measures of USFT and CSFT in lambs also showed significant and positive correlation (0.51). In kids the depth of tissue over the 3rd and 4th sternebrae and sternocostal cartilage between the 3rd and 4th sternebrae measured in vivo and carcass showed no significant differences between both measurements in both genetic groups. There were significant and positive correlations between variables in the sternal region measured in vivo and in carcass. It was concluded that LMA is higher in lambs than in kids, indicating a superior muscular performance in lambs. The 3 mm USFT as desired slaughter criterion was reached only by lambs, indicating a greater precocity of ovine species. The use of ultrasound was an effective method to estimate LMA and SFT of lambs and LMA and the depth of the sternal tissues of kids.