Modification of beef quality through steer age at slaughter, breed cross and growth promotants

Abstract

Girard, I., Aalhus, J. L., Basarab, J. A., Larsen, I. L. and Bruce, H. L. 2012. Modification of beef quality through steer age at slaughter, breed cross and growth promotants. Can. J. Anim. Sci. 92: 175–188. A 23 factorial experiment tested the interactions of slaughter age (12–13 or 18–20 mo), growth implants use (Component E-S, TE-S), ractopamine hydrochloride (RAC) feed supplementation use and breed cross [Hereford–Aberdeen Angus (HAA) or Charolais–Red Angus (CRA)] on pH, temperature, objective colour measurements, relative myoglobin states, sarcomere lengths, shear force, and water losses of m. semitendinosus (ST) and m. gluteus medius (GM) from 112 crossbred steers. In the ST, age affected objective colour measurements by increasing chroma and decreasing lightness (L*) and hue angle (P<0.05). Metmyoglobin (MMB) content of the ST also increased with steer age (P<0.05). In the GM, yearling-fed steers had greater MMB content than calf-fed steers, while hue angle varied the opposite way (P<0.05). Other variations in meat colour and myoglobin contents were more complex in the GM than the ST as they involved three-way interactions between the different treatments. Shear force and purge loss of the ST increased with implantation (P<0.05) with no change in sarcomere length (P>0.05). Shear force standard deviation was similar for breed crosses when yearling-fed but greatest for CRA breed cross when calf-fed (P<0.05). In both muscles, purge loss was increased by RAC supplementation (P<0.05). RAC supplementation did not affect sarcomere length and shear force in both muscles (P>0.10). In the GM, shear force increased with age and with CRA genetics (P<0.05). Results indicated that producers seeking to reduce beef toughness should consider using British crossbreds, exclude the use of hormonal implants and slaughter process steers at 12 to13 mo of age.

Meat quality of Limousin young bulls slaughtered at 6, 9 and 12 months of age

“…The similar tendency was observed for meat juiciness, whereas the aroma and flavour of the meat from the 6-month-old beef had the lowest scores (p<0.05), Table 2). The correlation results between slaughter age and beef tenderness, juiciness and aroma (Table 3) correspond to the results obtained by other authors (Lucero-Borja et al, 2014;Girard et al, 2012).…”

“…It is the most frequently observed beef quality defect that occurs mostly in the meat of young bulls (Węglarz 2010). In many studies the effects of different slaughter ages on beef meat quality has been examined (Ahnström et al, 2012;Lucero-Borja et al, 2014); however, most of them focused mainly on animals slaughtered at the age of more than 12 months (Bureš & Bartoň 2012;Girard et al, 2012;Humada et al, 2014). Only few publications concerned the meat quality of younger cattle (Prado et al, 2015;Araujo et al, 2016).…”

Effect of ractopamine on physicochemical characteristics and collagen solubility in finishing pigs

“…According to the length of sarcomere, when the muscle contracted it would have shorter sarcomere length then meat would likely to be tougher. ß-agronist did not affect the range of sarcomere length in Lambs [23] and in cattle [24]. In the present study, sarcomere length of pig fed with different levels of RAC were not significantly different thus RAC did not affected muscle contraction.…”

Contribution of myofibrillar and connective tissue components to the Warner–Bratzler shear force of cooked beef

“…Warner-Bratzler shear force and meat quality data were from a study described by Girard, Aalhus, Basarab, Larsen and Bruce (2011) and Girard, Aalhus, Basarab, Larsen and Bruce (2012). Inherent muscle characteristics (muscle fibre type, total and soluble collagen and proximate analyses) and meat quality (L*, a*, b*, myoglobin relative contents, purge loss, cooking loss, cooking time, sarcomere length and Warner-Bratzler shear force) data were originally presented by Girard et al (2011) and Girard et al (2012), respectively, and these data were used to investigate relationships between muscle properties, meat quality and the putative myofibrillar and connective tissue portions of the Warner-Bratzler shear force deformation curve.…”