Feed efficiency and carcass metrics in growing cattle1

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.

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Feed and production efficiency of young crossbred beef cattle stratified on a terminal total merit index1

Translational Animal Science ◽

10.1093/tas/txaa106 ◽

2020 ◽

Vol 4 (3) ◽

Author(s):

David N Kelly ◽

Stephen B Conroy ◽

Craig P Murphy ◽

Roy D Sleator ◽

Donagh P Berry

Keyword(s):

Beef Cattle ◽

Feed Intake ◽

Feed Efficiency ◽

Production Efficiency ◽

Carcass Traits ◽

Live Weight ◽

Carcass Weight ◽

Genetic Merit ◽

Validation Population ◽

Carcass Conformation

Abstract Few studies have attempted to quantify the association between a terminal total merit index with phenotypic feed and production efficiency in beef cattle, particularly when feed efficiency is itself explicitly absent as a goal trait in the index. The objective of the present study was to quantify the differences in phenotypic performance for feed intake, feed efficiency, and carcass traits of crossbred bulls, steers, and heifers differing in a terminal total merit index. A validation population of 614 bulls, steers, and heifers that were evaluated for feed intake and efficiency in the same feedlot and subsequently slaughtered at the end of their test period was constructed. The Irish national genetic evaluations for a terminal index of calving performance, docility, feed intake, and carcass traits were undertaken with the phenotypic records of animals present in the validation population masked. The validation population animals were subsequently stratified into four groups, within sex, according to their terminal index value. Mixed models were used to quantify the association between terminal genetic merit and phenotypic performance; whether the associations differed by sex were also investigated. The regression coefficient of phenotypic feed intake, carcass weight, carcass conformation, or carcass fat on its respective estimated breeding values was 0.86 kg dry matter 0.91 kg, 1.01 units, and 1.29 units, respectively, which are close to the expectation of one. On average, cattle in the very high terminal index stratum had a 0.63 kg DM/d lower feed intake, a 25.05 kg heavier carcass, a 1.82 unit better carcass conformation (scale 1 to 15), and a 1.24 unit less carcass fat score (scale 1 to 15), relative to cattle in the very low terminal index stratum. Cattle of superior total genetic merit were also more feed efficient (i.e., had a lower energy conversion ratio, lower residual feed intake, and greater residual gain), had a greater proportion of their live-weight as carcass weight (i.e., better dressing percentage) and were slaughtered at a younger age relative to their inferior total genetic merit counterparts. This study provides validation of an all-encompassing total merit index and demonstrates the benefits of selection on a total merit index for feed and production efficiency, which should impart confidence among stakeholders in the contribution of genetic selection to simultaneous improvements in individual animal performance and efficiency.

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GENETIC AND PHENOTYPIC PARAMETERS OF CARCASS TRAITS IN RAM LAMBS REARED ARTIFICIALLY IN A CONTROLLED ENVIRONMENT

Canadian Journal of Animal Science ◽

10.4141/cjas86-100 ◽

1986 ◽

Vol 66 (4) ◽

pp. 905-914 ◽

Cited By ~ 5

Author(s):

J. N. B. SHRESTHA ◽

A. FORTIN ◽

D. P. HEANEY

Keyword(s):

Carcass Traits ◽

Genetic Correlations ◽

Carcass Weight ◽

Research Centre ◽

Controlled Environment ◽

Kidney Fat ◽

Genetic And Phenotypic Correlations ◽

Ram Lambs ◽

Dressing Percentage ◽

Retail Cuts

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

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Influence of Crossbreeding of Ghezel Ram With Grey Shirazi Ewe on Growth Performance, Feed Efficiency and Carcass Traits of Fattening Lambs

10.21203/rs.3.rs-642724/v1 ◽

2021 ◽

Author(s):

Abdolhamid Karimi ◽

Mohammad Javad Abarghuei ◽

Alidad Boostani

Keyword(s):

Body Weight ◽

Growth Performance ◽

Feed Efficiency ◽

Average Daily Gain ◽

Carcass Traits ◽

Live Weight ◽

Carcass Weight ◽

Feed Conversion ◽

Final Body Weight ◽

Group 12

Abstract In this investigation, performance, feed efficiency and carcass traits of 48 weaned crossbred Grey Shirazi × Ghezel and purbred Grey Shirazi fattening lambs (mean live weight, 28.5 ± 0.5 kg and age, 115 ± 5 days) were evaluated. Lambs were divided into 4 groups contain the GM group (12 purebred male lambs of Grey Shirazi ewe × Grey Shirazi ram), the GF group (12 purebred female lambs of Grey Shirazi ewe × Grey Shirazi ram), the CM group (12 crossbred male lambs of Grey Shirazi ewe × Ghezel ram) and the CF group (12 crossbred female lambs of Grey Shirazi ewe × Ghezel ram). The dry matter intakes (DMI), average daily gain (ADG) and carcass traits in the lambs were determined. The DMI was greater in CF lambs compared to GF lambs (P < 0.001). Feed conversion ratio (FCR) was higher in male lambs comparing to female lambs (P = 0.001). The final body weight, ADG, live weight at the slaughtering and hot carcass weight (HCW) were lower in GF lambs compared to another lambs (P < 0.001, P = 0.003). Cold carcass weight (CCW) in CM lambs was higher than in other groups. The Longissimus dorsi (LD) area was higher in crossbreed male lambs (P = 0.001). Crossbreeding improved grow performance (final body weight and ADG) in male and female lambs. Carcass trait was improved by crossbreeding especially in male lambs. Sex effect on growth performance and carcass traits was noticeable and male lambs had superior growth.

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Evaluation of eleven cattle breeds for crossbred beef production: carcass data from males slaughtered at two ages

Animal Science ◽

10.1017/s0003356100004487 ◽

1990 ◽

Vol 50 (1) ◽

pp. 79-92 ◽

Cited By ~ 13

Author(s):

C. A. Morris ◽

R. L. Baker ◽

A. H. Carter ◽

S. M. Hickey

Keyword(s):

Carcass Traits ◽

Genetic Correlations ◽

Live Weight ◽

High Energy ◽

Carcass Weight ◽

Standard Errors ◽

Slaughter Weight ◽

Random Samples ◽

Slaughter Age ◽

Sire Breed

ABSTRACTAn experiment was carried out to compare sire breeds for carcass traits and to estimate heritabilities and phenotypic and genetic correlations. There were 1908 male cattle from 5 birth years. The sire breeds, each evaluated over three locations, were Blonde d'Aquitaine, Charolais, Chianina, Limousin, Maine Anjou, Simmental (four strains: Austrian, French (Pie Rouge), Swiss and West German) and South Devon (i.e. seven imported breeds) and Angus, Friesian, Hereford and Jersey (four local breeds), with a total of 161 sires represented. Each location contained Angus cows and additionally one location contained Hereford cows. Proportionally 0·72 of the cattle were slaughtered at about 20 months of age, whilst random samples from each of the first 4 years were retained for slaughter at about 31 months of age.Sire breeds ranked similarly for live weight at 13 months of age and for pre-slaughter weights at both 20 and 31 months of age. Relative to the Hereford-cross, the seven imported breeds were proportionally 0·054 to 0·072 heavier at slaughter (depending on slaughter age) and they had 0-065 to 0·077 heavier carcasses. Dressing proportions for the Blonde d'Aquitaine, Chianina and Limousin sire breeds were higher by at least 0007 units than for the Hereford-cross. The seven imported breeds were all leaner and had larger areas of m. longissimus than the Hereford-cross cattle. Friesian-crosses also had high live or carcass weights although they were intermediate for fat depth.The interaction of sire and dam breeds were only significant for fat depth (both slaughter ages) and for pre-slaughter and hot carcass weights (31-month slaughter age only). Interactions between sire breed and location were not important.Heritability estimates on data adjusted to a slaughter age of 595 days were: pre-slaughter weight 0·29, hot carcass weight 0·28, dressing proportion 0·14, fat depth 0·03 and m. longissimus area 0·30. Corresponding values on cattle whose records were adjusted to an age of 935 days were 0·56, 0·44, 0·39, 0·37 and 0·29. These values were from cattle grazed on pasture, and were generally lower than those from America (from cattle offered high energy rations). Phenotypic correlations among all pairs of traits were positive, whilst genetic correlations were positive for all pairs except those involving fat depth (where standard errors were large).

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Effects of crossbreeding Hungarian Merino sheep with Suffolk and Ile de France on carcass traits

Archives Animal Breeding ◽

10.5194/aab-52-169-2009 ◽

2009 ◽

Vol 52 (2) ◽

pp. 169-176

Author(s):

F. Pajor ◽

E. Láczó ◽

O. Erdős ◽

P. Póti

Keyword(s):

Carcass Traits ◽

Live Weight ◽

Carcass Composition ◽

Carcass Weight ◽

Merino Sheep ◽

Fattening Performance ◽

Percentage Weight ◽

Dressing Percentage ◽

And Gender ◽

Carcass Cuts

Abstract. In this examination, Hungarian Merino (ram n=30, ewe n=30), Hungarian Merino × Ile de France F1, and Hungarian Merino × Suffolk F1 (ram n=15, ewe n=15) lambs were used to evaluate the effect of crossbreeding on carcass characteristics and composition. We examined fattening performances and the following carcass traits: dressing percentage, weight of valuable carcass cuts, percentage of valuable meat, bone to meat ratio, and as well as meat conformation and fat cover (S/EUROP grading). In the present investigation, the weight at slaughter was fixed between 31–32 kg approximately, thus ensuring, weight would not affect carcass composition. Standardizing carcass weight allowed us to spot differences due to genotype and gender. The best results of fattening performance showed the Hungarian Merino × Ile de France F1 lambs (358 g/day). The tested crossed genotypes had not greatly influence dressing percentage and warm carcass weight, but the best percentage valuable carcass cuts had Hungarian Merino × Suffolk F1 (83.37 %). The best percentage of valuable meat presented (77.76 %) the Hungarian Merino × Ile de France F1 lambs. The best meat conformation and fat covered showed the Hungarian Merino × Suffolk F1 lambs. Hungarian Merinos showed less favourable results. To the summarising, the Suffolk and Ile de France improved the Hungarian Merino’s fattening performance, slaughter value and ability of market over 30 kg live weight, therefore there were both breeds suggest with crossing.

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401 Effect of zinc source and ractopamine hydrochloride on the growth performance and carcass characteristics of steers fed in confinement to harvest

Journal of Animal Science ◽

10.1093/jas/skz258.329 ◽

2019 ◽

Vol 97 (Supplement_3) ◽

pp. 160-160

Author(s):

John Wagner ◽

William T Nelson ◽

Terry Engle ◽

Jerry Spears ◽

Jeff Heldt ◽

...

Keyword(s):

Feed Efficiency ◽

Average Daily Gain ◽

Carcass Characteristics ◽

Feedlot Cattle ◽

Beef Steers ◽

Live Animal ◽

Zinc Source ◽

Dressing Percentage ◽

Ractopamine Hydrochloride ◽

Daily Gain

Abstract Four hundred and thirty-two beef steers (346.3 ± 63.7 kg BW) were used to determine the effects of Zn source on feedlot cattle fed ractopamine hydrochloride. Cattle were blocked in groups of 54 by BW and housed in 48 pens containing 9 steers per pen. Pens within a weight block were randomly assigned to treatments in a 2 x 3 factorial arrangement, with factors being: 1) 0 or 30.1 mg of ractopamine HCl/kg DM fed during the final 29 days on feed; and 2) Zn source: 90 mg of supplemental Zn/kg DM from ZnSO4; Zn sulfate (67%) + Zn methionine (33%); and Zn from Zn hydroxychloride, fed through the entire feeding period. Cattle were fed a high concentrate finishing diet for 154 d and slaughtered at a commercial abattoir. Average daily gain, DMI, feed efficiency and carcass characteristics were determined after slaughter. Zinc source had no impact on live animal performance. Cattle fed ractopamine HCl had greater (P < 0.01) final BW, greater (P < 0.001) ADG, improved (P < 0.001) G:F, heavier (P < 0.01) HCW, and larger (P < 0.05) longissimus muscle compared to non-ractopamine supplemented steers. There was a Zn source by ractopamine interaction (P < 0.01) for dressing percentage. Cattle receiving ractopamine HCl with Zn hydroxychloride had a greater dressing percentage (P < 0.05) when compared to ractopamine HCl cattle fed other Zn sources. Cattle receiving ractopamine HCl with Zn sulfate had a lesser dressing percentage (P < 0.05) when compared to ractopamine HCl cattle fed other Zn sources. Additional Zn source by ractopamine HCl interactions were not significant. These data indicate that Zn source has minimal impacts on feedlot steer performance and carcass characteristics when supplemented to cattle receiving 0.0 or 30.1 mg of ractopamine HCl/kg DM.

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Canonical correlation analysis of body measurements and carcass traits of cross bred rabbit population

Biotechnology in Animal Husbandry ◽

10.2298/bah1204855o ◽

2012 ◽

Vol 28 (4) ◽

pp. 855-861 ◽

Cited By ~ 1

Author(s):

D.M. Ogah

Keyword(s):

Correlation Analysis ◽

Body Length ◽

Canonical Correlation Analysis ◽

Canonical Correlation ◽

Carcass Traits ◽

Carcass Weight ◽

Body Measurements ◽

Slaughter Weight ◽

Dressing Percentage ◽

Criterion Variables

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.

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Genetic correlations among indicator traits for carcass composition measured in yearling beef bulls and finished feedlot steers

Canadian Journal of Animal Science ◽

10.4141/a05-013 ◽

2005 ◽

Vol 85 (4) ◽

pp. 463-473 ◽

Cited By ~ 7

Author(s):

R. Bergen ◽

S. P. Miller ◽

J. W. Wilton

Keyword(s):

Genetic Correlation ◽

Carcass Traits ◽

Genetic Correlations ◽

Carcass Composition ◽

Carcass Weight ◽

Muscle Size ◽

Longissimus Muscle ◽

Muscle Area ◽

Feedlot Steers ◽

Beef Bulls

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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The effect of age, live-weight and rate-of-gain on dressing percentage and non-saleable fat content of Israel-Friesian bull calves

Animal Science ◽

10.1017/s0003356100038332 ◽

1967 ◽

Vol 9 (1) ◽

pp. 115-119 ◽

Cited By ~ 5

Author(s):

D. Levi ◽

M. Soller ◽

A. Shilo

Keyword(s):

Genetic Correlation ◽

Live Weight ◽

Fat Content ◽

Carcass Weight ◽

Bull Calves ◽

Kidney Fat ◽

Dressing Percentage ◽

Highly Correlated ◽

Effect Of Age

Data were collected during 1961–2 on the live-weight, age and warm carcass weights of 83 lots of Israel-Friesian bull calves, 525 animals in all, the offspring of 26 sires. For varying numbers of these animals weight of various non-saleable fat components, including ruminal fat, kidney fat, inguinal fat and scapular fat were also obtained. Ruminal fat alone and ruminal fat plus kidney fat were found to be highly correlated with total non-saleable fat (r = 0·84 and 0·94, respectively). Heritability of dressing percentage was 0·20, of live-weight rate-of-gain 0·92, and of carcass rate-ofgain 0·49. The genetic correlation between live-weight and carcass weight was 0·7. Between-lot correlations indicated that increased rate-of-gain achieved through management will be accompanied by decreased dressing percentage and increased non-saleable fat content.

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A study on comparison of fattening performances and some slaughter characteristics of Suffolk and German Mutton Merino lambs under intensive fattening conditions

Indian Journal of Animal Research ◽

10.18805/ijar.b-748 ◽

2017 ◽

Author(s):

Mikail Arslan ◽

Orhan Yilmaz ◽

Huseyin Denk

Keyword(s):

Feed Efficiency ◽

Carcass Weight ◽

Retail Sale ◽

Slaughter Weight ◽

Weight Gains ◽

Dressing Percentage ◽

Integrated Facility

The study carried out at Dort Mevsim Meat Integrated Facility in Susurluk district, Balikesir province, Turkey. In each genotype, there were 20 male lambs. Suffolk and German Mutton Merino lambs were subjected to fattening for 70 days. At the end of the trial, 6 male lambs from each genotype were slaughtered. Slaughter weight, ADG, concentrate feed efficiency, hot carcass weight, chilling carcass weight, hot dressing percentage and chilling dressing percentage were 43.9 kg, 301 g, 3.44 kg, 23.18 kg, 22.24 kg, 52.80 % and 50.66 % in Suffolk lambs; these values were 43.1 kg, 296 g, 3.86 kg, 21.85 kg, 20.89 kg, 50.70 % and 48.47 % in German Mutton Merino lambs, respectively. Hot and chilling carcass weights of Suffolk and German Mutton Merino lambs were significantly different (P>0.05). The findings of the current study showed that Suffolk lambs tended to have higher hot and chilling carcass weights, although there were no statistical differences between the two genotypes in terms of slaughter weights, average daily weight gains and other slaughter traits. These results also indicate that the carcasses for retail sale from the Suffolk lambs were more in quantity when compared to German Mutton Merino lambs.

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