The effect of conditioning period on loin muscle tenderness in crossbred lambs with or without the Texel muscling QTL (TM-QTL)

• Published in: Meat science Vol. 85; no. 4; pp. 715 - 720
• Main Authors: Lambe, N.R., Haresign, W., Macfarlane, J., Richardson, R.I., Matika, O., Bünger, L.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01.08.2010; [Amsterdam]: Elsevier Science; Elsevier
• Subjects: Animals; Biological and medical sciences; business enterprises; carcass weight; Chromosome Mapping - veterinary; chromosomes; Chromosomes, Mammalian; crossbreds; Crosses, Genetic; ewes; Female; Food Handling - methods; Food industries; Food Technology; Fundamental and applied biological sciences. Psychology; Genotype; Hybridization, Genetic; lamb meat; Lambs; loins; loins (meat cut); Male; Meat - standards; Meat and meat product industries; Meat eating quality; Meat quality; meat tenderness; mules; Muscle, Skeletal; muscles; Muscularity; Organ Size - genetics; QTL; Quantitative Trait Loci; rams; Sheep - genetics; Stress, Mechanical; Texel; QTL; Texel; Muscularity; Lambs; Meat eating quality; Meat quality; Quality; Tenderness; Meat product; Muscle; Meat
• ISSN: 0309-1740; 1873-4138
• DOI: 10.1016/j.meatsci.2010.03.029

A Texel muscling quantitative trait locus (TM-QTL) has been identified on chromosome 18, which increases loin muscling, but may also have a negative impact on mechanically-measured loin tenderness in crossbred lambs, depending on conditioning time. This study investigated the influence of a range of conditioning times (3, 5, 7 or 9 days) on the effect of TM-QTL on loin muscle tenderness. Using Texel rams heterozygous for TM-QTL, mated to non-carrier Mule ewes, heterozygous ( n = 45) and wild-type ( n = 50) crossbred lambs were produced. Weight of the valuable Longissimus lumborum muscle was higher in TM-QTL carriers than non-carriers, when compared at a fixed age (+11.5%; P = 0.038), with the same trend at a fixed carcass weight (+10.2%; P = 0.064). Toughness, measured by shear force, was significantly higher in samples from TM-QTL carriers than non-carriers, after conditioning for 3 days ( P = 0.002), 5 days ( P = 0.003) or 7 days ( P = 0.03), but was not significantly different after 9 days of conditioning ( P = 0.32). Compared to non-carrier lambs, the proportion of samples above consumer acceptability thresholds for toughness was greater in the TM-QTL carrier lambs after 3 and 5 days of conditioning, similar at 7 days, but lower at 9 days. The results suggest that the negative effect of TM-QTL on loin tenderness in crossbred lambs can be overcome by conditioning for more than 7 days. Marketing of TM-QTL carrier lambs through companies that use enhanced processing protocols could be beneficial, due to higher loin muscle weights, without negative effects on meat quality.