A comparison of carcass traits in Scottish Blackface and Welsh Mountain lambs and their crosses

1984 ◽  
Vol 39 (3) ◽  
pp. 433-440 ◽  
Author(s):  
G. J. Lee

ABSTRACTA total of 219 lambs of the Welsh Mountain (W) and Scottish Blackface (B) breeds, and six types of crossbred with varying proportions of the two breeds from a cyclical crossbreeding experiment, were slaughtered in six groups at fortnightly intervals from 6 to 8 months of age. Each group had balanced numbers of each genotype and each sex. Genotype differences and effects of heterosis were estimated. Fat grades were assessed by farm staff before slaughter and Meat and Livestock Commission fat and conformation scores and external linear hindquarter measurements of each carcass were recorded.At the same age, W carcasses were lighter (W: B = 0·86, W = 11·7 kg, B = 13·4 kg) but were more mature and had more kidney fat (W: B = 1·73) and higher fat and conformation scores especially in the loin region, but relatively shorter, thinner legs. At the same degree of maturity (carcass weight/estimated mature carcass weight), the Welsh carcasses had more kidney fat but the difference in leg measurements was reduced, and the differences for fat and conformation scores disappeared. When compared at the same grade, the Welsh lambs were 2 kg lighter and had higher conformation scores suggesting comparative undergrading, especially by the farm assessors. Results for crossbred lambs were as predicted from their breed composition and there was no evidence of heterosis.The results suggest that at the same estimated carcass fatness, the Blackface has the potential to produce a heavier carcass but is later maturing, taking approx. 12 days longer to reach this degree of fatness.

1986 ◽  
Vol 66 (4) ◽  
pp. 905-914 ◽  
Author(s):  
J. N. B. SHRESTHA ◽  
A. FORTIN ◽  
D. P. HEANEY

Genetic and phenotypic relationships among carcass traits were calculated for 654 ram lambs from 210 sires of three synthetic strains developed at the Animal Research Centre. Lambs were housed indoors in a controlled environment on expanded metal floors and reared artificially with milk replacer and solid diets. Paternal half-sib estimates of heritability at 36-kg body weight and 116 of age were moderate to high ranging from 0.38 to 0.67 for shoulder and leg (trimmed and lean), total trimmed retail cuts, total lean, chilled carcass weight and lean weight per day (P < 0.01). Estimates of phenotypic and genetic correlations between the above traits showed a significantly favorable relationship indicating their usefulness as criteria in selection for meatiness. Heritability estimates for front, back and total in rough retail cuts, trimmed loin cuts, lean in rack and loin, kidney fat weight and dressing percentage ranged from −0.19 to 0.27 (P > 0.05). Estimates involving loin, rack, front, back, total retail cuts, kidney fat wt, dressing percentage and chilled carcass weight per day showed lower and nonsignificant relationships with total trimmed retail cuts or total lean. Key words: Sheep, heritability, genetic and phenotypic correlations, lamb carcass traits


1970 ◽  
Vol 12 (2) ◽  
pp. 281-290 ◽  
Author(s):  
H. P. Donald ◽  
J. L. Read ◽  
W. S. Russell

SUMMARYIn order to obtain a wide range of live weights, two Oxford Down, two Southdown, and two Soay rams of recent feral origin, were used to sire lambs from 169 crossbred ewes. These ewes had been bred from Blackface ewes mated to Border Leicester, Dorset Hora, Clun Forest, Finnish Landrace and Tasmanian Merino rams. Of the 282 lambs weaned by the crossbred ewes, 61 were singles, 166 twins, 51 triplets and 4 quadruplets. Carcass data were obtained from all but three of them.Oxford Down cross lambs were, in terms of fitted values, 10 kg heavier and 4 days younger than Soay cross lambs and 6 kg heavier and 2 days younger than Southdown cross lambs when slaughtered. Twins and triplets were 1·4 and 2·1 kg, respectively, lighter than singles and were 37 and 58 days older than singles. Ewes of the heaviest groups produced heavier lambs in a shorter time than ewes of the lightest groups.The Soay cross lambs showed a higher killing-out percentage, less tail fat, and more kidney fat, than the Southdown and Oxford Down cross lambs.Carcass characters made little if any difference to the price paid for the lambs which depended mainly on weight. Receipts from lambs were highest when the most fertile ewes were mated to the largest rams.


2012 ◽  
Vol 28 (4) ◽  
pp. 855-861 ◽  
Author(s):  
D.M. Ogah

In this study, canonical correlation analysis was applied to estimate the relationship between body measurements and carcass traits of 28 male cross bred rabbits of about 12 weeks of age, reared under semi intensive system. Four body measurements, pre-slaughter weight (PSW) , body length (BL), chest circumference (CC), and ear length (EL) as predictor variable while dressing percentage ( DP) , hot carcass weight (HCW) and cold carcass weight (CCW) as criterion variables. Pre-slaughter weight and body length had significant (P<0.001) simple correlation coefficients with the carcass traits except for dressing percentage. The three canonical variate pairs ranged between .99 to .42 and only the first pair was significant (P<0.001). From the analysis pre-slaughter weight and body length can be regarded as the main factors as live measurement traits, while dressing percentage did not have pronounced effect on the emerged criterion variables.


2020 ◽  
Vol 4 (3) ◽  
Author(s):  
Warren C Rusche ◽  
Julie Ann Walker ◽  
Peter Sexton ◽  
Rebecca S Brattain ◽  
Zachary K Smith

Abstract Crossbred beef steers with a high percentage of Angus ancestry [n = 240, initial shrunk body weight (BW), 404 ± 18.5 kg] were used in a 117-d feedlot experiment to evaluate the effect of hybrid rye (Rye; KWS Cereals USA, LLC, Champaign, IL) as a replacement for dry-rolled corn (DRC) on growth performance, carcass traits, and comparative net energy (NE) value in diets fed to finishing steers. Rye from a single hybrid (KWS Bono) with an ergot alkaloid concentration of 392 ppb was processed with a roller mill to a processing index (PI) of 78.8 ± 2.29. Four treatments were used in a completely randomized design (n = 6 pens/treatment; 10 steers/pen), where DRC (PI = 86.9 ± 4.19) was replaced by varying proportions of Rye [DRC:Rye, dry matter (DM) basis (60:0), (40:20), (20:40), and (0:60)]. Liver abscess scores and carcass characteristics were collected at the abattoir. Carcass-adjusted performance was calculated from hot carcass weight (HCW)/0.625. Performance-adjusted NE was calculated using carcass-adjusted average daily gain (ADG), DM intake (DMI), and mean equivalent shrunk BW with the comparative NE values for rye calculated using the replacement technique. Data were analyzed using the GLIMMIX procedure of SAS 9.4 (SAS Inst. Inc., Cary, NC) with pen as the experimental unit. Treatment effects were tested using linear and quadratic contrasts, as well as between diets with and without Rye. Replacing DRC with Rye linearly decreased (P ≤ 0.01) carcass-adjusted final BW, ADG, DMI, and gain:feed (G:F). Feeding rye linearly decreased HCW and longissimus muscle area (P ≤ 0.04). Distributions of liver scores and USDA grades for quality and yield were unaffected by treatment (P ≥ 0.09). Estimated replacement NE for maintenance (NEm) and gain (NEg) values for rye, when included at 60% of diet DM, were 1.90 and 1.25 Mcal/kg, respectively. Rye can be a suitable feed ingredient in finishing diets for feedlot steers. Estimated replacement values of Rye when fed at 60% of diet DM closely agreed with current tabular standards but, when included at 20% of diet DM, estimated NEm and NEg values of Rye were increased 9.5% and 12.8%, respectively. Net energy value of Rye for gain is approximately 84% compared to DRC; thus, the complete replacement of DRC with Rye depressed DMI, ADG, G:F, and carcass weight.


1971 ◽  
Vol 77 (2) ◽  
pp. 317-323 ◽  
Author(s):  
M. A. Price

SummaryThe carcass characteristics of a total of 43 infertile bulls were oompared with those of 42 steers from five independent trials. In most cases there was no significant difference between the bulls and the steers for dressing percentage, or fleshing index. Bulls were generally found to have greater hide percentages than steers, the difference being very highly significant (P < 0·001) in one of the trials and significant (P < 0·05) in another. Eye musole area expressed relative to caroass weight was greater in the bulls, the difference being significant (P < 0·05) in three of the trials. The depth of fat over the eye musole and the hind to fore-quarter weight ratio were greater in the steer carcasses. Head weights were found to be significantly greater (P < 0·05) and caul and kidney fat weights less (P < 0·05) in bulls than in steers in the one trial where these parameters could be measured.Carcass composition was estimated by the three-rib sample joint teohnique in four of the trials, and in these the bulls had a greater percentage of bone and muscle, but a lower peroentage of fat than the steers, the differences being significant in most oases. In the fifth trial composition was estimated by half carcass dissection. This, too, showed bulls to have a greater percentage of bone and muscle and a lower percentage of fat, the differences being highly significant (P < 0·01) and very highly significant (P < 0·001) respectively. On a fat-corrected basis the estimated retail value of the carcasses favoured the bulls by about $20.00 each.The studies, conducted over a range of nutritional conditions, showed that non-castration favoured muscle growth while suppressing fat deposition, and that this advantage was more pronounced when growth rates were high.


1991 ◽  
Vol 42 (8) ◽  
pp. 1373 ◽  
Author(s):  
HM Burrow ◽  
HM Burrow ◽  
B Gulbransen ◽  
B Gulbransen ◽  
SK Johnson ◽  
...  

Thirty-five steers and 37 heifers were grown at pasture and finished in a feedlot to meet Australian domestic market specifications, i.e. 160-200 kg carcass weight with 5-9 mm subcutaneous fat at the P8 rump site. The animals were from lines that had been selected for either high growth rate to 600 days (UPWT) or for low rectal temperature under conditions of high ambient temperatures (TEMP) and from a control line (CONT). They were slaughtered in six groups at fortnightly intervals when liveweight of individuals was estimated to satisfy market requirements. Animals from the UPWT line were heavier at all ages than animals from the TEMP and CONT lines (P< 0.05) and had higher liveweight gains at pasture (P < 0.01). There was no difference between the lines in liveweight gains in the feedlot. At the same carcass weight, UPM animals had leaner carcasses (P < 0.01) but similar levels of marbling to CONT line animals. TEMP line animals were also leaner than CONT line animals (P < 0.0l ) , but had more marbling (P<0.01). There was no significant difference between lines in feed conversion efficiency. Steers were heavier (P < 0.001) than heifers at all ages, grew faster (P < 0.001) except during the immediate post-castration period, had higher feed intakes (P < 0.05) but better feed conversion efficiencies (P < 0.05), and at the same carcass weight were leaner (P < 0-01) and had less marbling (P < 0.05). Meat colour, cooking loss, ultimate pH and meat tenderness did not differ significantly between lines or sexes. These results are discussed with reference to the use of selection for growth or heat resistance to improve growth and carcass traits of beef herds in tropical areas.


2008 ◽  
Vol 48 (9) ◽  
pp. 1194 ◽  
Author(s):  
K. L. Pearce ◽  
D. G. Masters ◽  
R. H. Jacob ◽  
D. L. Hopkins ◽  
D. W. Pethick

Under commercial conditions in Australia, lambs are often dehydrated at slaughter despite access to water at the abattoir. Dehydration results in reduced fluid content of meat, which causes liveweight and carcass weight loss. Two experiments evaluated hydration status and carcass characteristics in lambs fed increased levels of sodium chloride (salt) and/or betaine before slaughter. Both experiments were 2 × 2 factorial designs with two levels of salt added [0 and 50 g/kg dry matter (DM)] and two levels of betaine added (0 and 6.7 g/kg DM) to the diets. The treatment diets were introduced to sheep over a 7–8-day period and then fed at 1.5 kg/day for the following 7 days. In experiment 1, 96 Poll Dorset–Merino cross wether lambs (45.9 ± 0.17 kg) were fed in individual pens and in experiment 2, 204 Merino wether lambs (43.1 ± 0.35 kg) were fed in group pens. In the first experiment, water and feed were withheld from the end of the treatment feeding period until slaughter 48 h later. In the second experiment, feed and water were withheld for the first 24 h after treatment but water was available for the next 24 h immediately before slaughter. In both experiments, consumption of the high salt diet decreased urine specific gravity and osmolarity at the end of the feeding period and after 24 h without access to water. This indicates an improved hydration status at this time. However, the difference in hydration status related to feeding salt declined during the 48-h lairage period and there were no significant differences in hot carcass weight or muscle DM among groups at slaughter. It could be concluded from this result that the addition of salt has little commercial value; however, this may not be the case. The lambs in experiment 2 did not behave according to industry expectations. They all drank water in the last 24 h in lairage and none of the groups showed severe dehydration. Further research is justified to determine if the lambs fed the diets with no added salt drunk in lairage as a learned response from the lambs fed salt and, if so, whether this can be developed into a commercial strategy. Feeding betaine did not result in any changes in hydration status or carcass characteristics.


2019 ◽  
Vol 97 (11) ◽  
pp. 4405-4417 ◽  
Author(s):  
David N Kelly ◽  
Craig Murphy ◽  
Roy D Sleator ◽  
Michelle M Judge ◽  
Stephen B Conroy ◽  
...  

Abstract Some definitions of feed efficiency such as residual energy intake (REI) and residual gain (RG) may not truly reflect production efficiency. The energy sinks used in the derivation of the traits include metabolic live-weight; producers finishing cattle for slaughter are, however, paid on the basis of carcass weight, as opposed to live-weight. The objective of the present study was to explore alternative definitions of REI and RG which are more reflective of production efficiency, and quantify their relationship with performance, ultrasound, and carcass traits across multiple breeds and sexes of cattle. Feed intake and live-weight records were available on 5,172 growing animals, 2,187 of which also had information relating to carcass traits; all animals were fed a concentrate-based diet representative of a feedlot diet. Animal linear mixed models were used to estimate (co)variance components. Heritability estimates for all derived REI traits varied from 0.36 (REICWF; REI using carcass weight and carcass fat as energy sinks) to 0.50 (traditional REI derived with the energy sinks of both live-weight and ADG). The heritability for the RG traits varied from 0.24 to 0.34. Phenotypic correlations among all definitions of the REI traits ranged from 0.90 (REI with REICWF) to 0.99 (traditional REI with REI using metabolic preslaughter live-weight and ADG). All were different (P < 0.001) from one suggesting reranking of animals when using different definitions of REI to identify efficient cattle. The derived RG traits were either weakly or not correlated (P > 0.05) with the ultrasound and carcass traits. Genetic correlations between the REI traits with carcass weight, dressing difference (i.e., live-weight immediately preslaughter minus carcass weight) and dressing percentage (i.e., carcass weight divided by live-weight immediately preslaughter) implies that selection on any of the REI traits will increase carcass weight, lower the dressing difference and increase dressing percentage. Selection on REICW (REI using carcass weight as an energy sink), as opposed to traditional REI, should increase the carcass weight 2.2 times slower but reduce the dressing difference 4.3 times faster. While traditionally defined REI is informative from a research perspective, the ability to convert energy into live-weight gain does not necessarily equate to carcass gain, and as such, traits such as REICW and REICWF provide a better description of production efficiency for feedlot cattle.


2005 ◽  
Vol 85 (4) ◽  
pp. 463-473 ◽  
Author(s):  
R. Bergen ◽  
S. P. Miller ◽  
J. W. Wilton

Genetic correlations were examined among 10 live growth and ultrasound traits measured in yearling beef bulls (n = 2172) and four carcass traits measured in crossbred finished feedlot steers (n = 1031). Heritabilities ranged from 0.13 (bull ultrasound longissimus muscle width) to 0.83 (yearling bull hip height). Genetic correlations indicated that selecting yearling bulls for increased growth rate and hip height would lead to higher carcass weight, increased longissimus muscle area and reduced levels of carcass marbling in steers. Bull ultrasound fat depth was positively associated with both carcass fat depth and marbling score. Most ultrasound longissimus muscle size measurements in bulls were positively associated with each other and with carcass longissimus muscle area in steers, but the magnitude of the genetic correlation with carcass measurements depended on the bull longissimus muscle size trait in question. This suggests that longissimus muscle shape in bulls may be related to carcass weight, fat and muscle traits in steers. Results confirm that while ultrasound is a valuable tool for the genetic improvement of carcass traits in beef cattle, genetic correlations between live bull ultrasound and steer carcass traits less then unity suggest that selection would benefit from multiple trait evaluations in situations where reliable carcass data are available. Key words: Ultrasound, beef carcass, heritability, genetic correlation


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