Manual on E.A.A.P. Reference Methods for the assessment of carcass characteristics in cattle

This study examined the relationship of muscular and skeletal scores and ultrasound measurements in the live animal, and carcass conformation and fat scores with carcass composition and value using 336 steers, slaughtered at 2 years of age. Live animal scores and measurements were recorded at 8 to 12 months of age and pre-slaughter. Following slaughter, each carcass was classified for conformation and fatness and the right side dissected into meat, fat and bone. Carcass conformation scores and fat scores were both measured on a continuous 15-point scale and ranged from 2.0 to 12.0 and from 2.8 to 13.3, respectively. Pre-slaughter muscular scores showed positive correlations ( P , 0.001) ranging from 0.31 to 0.86 with carcass meat proportion, proportion of high-value cuts in the carcass, conformation score and carcass value, significant negative correlations with carcass fat (r 5 20.13) and bone (r 5 20.81) proportions, and generally low non-significant relationships with the proportion of high-value cuts in meat and carcass fat score. Pre-slaughter ultrasound muscle depth and carcass conformation score showed similar correlations with carcass traits to those using the pre-slaughter muscular scoring procedure. Pre-slaughter ultrasound fat depth showed positive correlations ( P , 0.001) with carcass fat proportion (r 5 0.59) and fat score (r 5 0.63), and significant negative correlations (20.23 to 20.50) with carcass meat and bone proportions, high-value cuts in the carcass and in meat, and carcass value. Pre-slaughter skeletal scores generally showed poor correlations ranging from 20.38 to 0.52 with the various carcass traits. Corresponding correlations (20.26 to 0.44) involving records collected at 8 to 12 months of age were lower than those using pre-slaughter records. A one-unit increase in carcass conformation score increased carcass meat proportion and value by 11.2 g/kg and 5.6 cents/kg, respectively. Corresponding values for fat score were 28.2 g/kg and 25.1 cents/kg. In conclusion, both pre-slaughter live animal scores/measurements and carcass classification scores, explained an appreciable amount of the total variation in carcass meat, fat and bone proportions and carcass value, and a moderate amount of the variation in proportion of high-value meat cuts in the carcass.

Section: Assessorssupporting

confidence: 61%

The relationship of live animal muscular and skeletal scores, ultrasound measurements and carcass classification scores with carcass composition and value in steers

Conroy

Drennan

Kenny

et al. 2009

“…At this moment, carcasses were weighed and dressing percentage (DP) was calculated. At this point, the left half-carcasses were moved to the research center pilot plant and the following carcass measurements were collected: length of carcass (LC), length of leg (LL), width of leg (WL) and internal depth of chest (IDC) as described by De Boer et al (1974), whereas external depth of chest (EDC) and perimeter of leg (PL) were also obtained. These parameters were determined to assess carcass morphology.…”

Section: Methodsmentioning

confidence: 99%

The effect of livestock production system and concentrate level on carcass traits and meat quality of foals slaughtered at 18 months of age

Lorenzo¹,

Crecente

Sarriés

et al. 2014

This trial was conducted to study the effect of livestock production system (freedom extensive system (FES) v. semi extensive system (SES)) and amount of finishing feed (1.5 v. 3.0 kg of commercial feed) in SES on carcass characteristics, meat quality and nutritional value of meat foal slaughtered at 18 months of age. For this study, a total of 49 foals (21 from FES and 28 from SES) were used. The obtained results showed that SES had a positive influence on carcass characteristic because these foals showed the best values for live weight, carcass weight, dressing percentage, perimeter of leg (PL) and carcass compactness index. On the other hand, finishing feeding also had a significant ( P < 0.05) effect on PL and lean thickness, as the highest values were obtained in foals finished with 3 kg of commercial fodder. The physico-chemical properties were significantly affected by the livestock production system with the exception of ashes content ( P > 0.05). Foals finished in SES increased in 408% the intramuscular fat content (0.23 v. 1.17%, for foals reared in FES and SES, respectively). On the other hand, L*-value and a*-value were significantly ( P < 0.01) affected by livestock production system, as foals from the FES group had a more intense redder color (higher CIE a*-value) and higher lightness (higher CIE L*-value) compared with those from the SES group. Finally, meat nutritional value was significantly affected by livestock production system, as foals from an extensive production system on wood pasture could be considered as healthier in relation to their fatty acid profiles (low n-6/n-3 ratio and high hypocholesterolemic/hypercholesterolemic ratio) as a result of the beneficial grass intake on meat fatty acid profile.

“…Within the range 6 one-third of a class, this machine had a correspondence with reference panel (three experienced classifiers) values of 100% for conformation class and 97% for fat class (Allen and Finnerty, 2000). Perirenal plus retroperitoneal fat weight, together with carcass measurements (DeBoer et al, 1974), were also recorded. Carcass measurements that were taken were carcass length, chest depth, leg length, leg width (maximum width of leg) and leg thickness (width of leg from the medial splitting surface of the symphysis pubis).…”

Section: Management During Finishingmentioning

confidence: 99%

Effects of genetic merit for carcass weight, breed type and slaughter weight on performance and carcass traits of beef × dairy steers

Keane

Dunne

Kenny

et al. 2011

Crossbreeding of Holstein-Friesian dairy cows with both early maturing (e.g. Aberdeen Angus (AA)) and late maturing (e.g. Belgian Blue (BB)) beef breeds is commonly practised. In Ireland, genetic merit for growth rate of beef sires is expressed as expected progeny difference for carcass weight (EPD CWT ). The objective of this study was to compare the progeny of Holstein-Friesian cows, sired by AA and BB bulls of low (L) and high (H) EPD CWT for performance and carcass traits. A total of 118 spring-born male progeny from 20 (9 AA and 11 BB) sires (8 L and 12 H) were managed together from shortly after birth to about 19 months of age. They were then assigned to one of two mean slaughter weights (560 kg (light) or 620 kg (heavy)). Following slaughter, carcasses were graded for conformation class and fat class, the 6th to 10th ribs joint was dissected as an indicator of carcass composition, and samples of subcutaneous fat and musculus longissimus were subjected to Hunterlab colour measurements. A sample of m. longissimus was also chemically analysed. Slaughter and carcass weights per day of age for AAL, AAH, BBL and BBH were 747, 789, 790 and 805 (s.e. 10.5) g, and 385, 411, 427 and 443 (s.e. 4.4) g, respectively. Corresponding carcass weight, kill-out proportion, carcass conformation class (scale 1 to 5) and carcass fat class (scale 1 to 5) values were 289, 312, 320 and 333 (s.e. 4.0) kg, 516, 522, 542 and 553 (s.e. 3.5) g/kg, 2.5, 2.4, 3.0 and 3.1 (s.e. 0.10), and 3.4, 3.5, 2.9 and 2.8 (s.e. 0.11). There were few breed type 3 genetic merit interactions. Delaying slaughter date increased slaughter weight, carcass weight and all measures of fatness. It also reduced the proportion of carcass weight in the hind quarter and the proportions of bone and muscle in the ribs joint. None of these effects accompanied the increase in carcass weight due to higher EPD CWT . It is concluded that BB have superior production traits to AA. Selection of sires for higher EPD CWT increases growth rate, kill-out proportion and carcass weight of progeny with little effect on carcass or muscle traits. The extra carcass weight due to higher EPD CWT is more valuable commercially than a comparable carcass weight increment from a delay in slaughter date because it comprises a higher proportion of muscle.