An economic selection index for lean meat production in New Zealand sheep

1987 ◽  
Vol 45 (3) ◽  
pp. 465-475 ◽  
Author(s):  
G. Simm ◽  
M. J. Young ◽  
P. R. Beatson
Keyword(s):  
New Zealand ◽  
Selection Index ◽  
Live Weight ◽  
Breeding Value ◽  
Index Selection ◽  
Meat Production ◽  
Total Fat ◽  
Terminal Sire ◽  
Economic Selection ◽  
Lean Weight

ABSTRACTAn economic selection index was derived for terminal sire sheep breeds or strains, using physical and financial results from New Zealand export lamb-producing flocks. The aggregate breeding value of the index comprised carcass lean weight and carcass total fat weight. Index measurements were live weight, ultrasonic fat depth and ultrasonic muscle depth. Economic values used for lean and fat weights (NZ$5·65 and NZ$–1·2 per kg, respectively) were the change in profit per kg increase in lean or fat weight from that in the average carcass of lambs slaughtered in 1984/85. The s.d. of the aggregate breeding value was NZS3·20, and the correlation between the full index and the aggregate breeding value was 0·23. This correlation fell to 0·18, 0·15 and 0·07, respectively, when muscle depth or fat depth or muscle and fat depths were omitted from the index. Selection on the full index, or on the index omitting muscle depth was expected to lead to an increase in carcass lean weight and a slight decrease in carcass fat weight. Selection on the index omitting fat depth, or selection on live weight alone, was expected to lead to an increase in both fat and lean weights.

A selection index for lean meat production in sheep

1993 ◽  
Vol 1987 ◽  
pp. 59-59
Author(s):  
G. Simm ◽  
W.S. Dingwall
Keyword(s):  
Selection Index ◽  
Live Weight ◽  
High Energy ◽  
Carcass Composition ◽  
Meat Production ◽  
Lean Meat ◽  
In Vivo Measurements ◽  
Terminal Sire ◽  
Protein Feed

It is generally accepted that leanness of terminal sire sheep breeds should be increased. However, it is very difficult to define formally a selection goal for these breeds. Put loosely, at a given age, we probably require terminal sires with as much extra lean meat as possible, whilst minimising any increase in fat weight. In the past, selection has been mainly on weight for age, but this may actually increase fatness at the age of selection.Intuitively we expect some in vivo measurements of carcass composition to help in achieving the selection goal. In practice, in vivo measurements of carcass composition in sheep are often imprecise, though the treatment of the animals can affect the relative precision. Ad libitum feeding on a high energy, high protein feed appears to increase the variation in carcass composition of ram lambs compared to those on a lower plane of nutrition (Simm et al, 1985 compared to Cuthbertson et al, 1983). Under these conditions we were able to predict carcass composition reasonably precisely from live weight and ultrasonic measurements (means and original and residual s.d.s for carcass lean weight: 18.30, 1.60 and l.00 kg and for fat weight 13.74, 2.70 and 0.96 kg).

scholarly journals Simulation Study on the Integration of Health Traits in Horse Breeding Programs

Animals ◽  
2020 ◽  
Vol 10 (7) ◽  
pp. 1153
Author(s):  
Lisa Büttgen ◽  
Johannes Geibel ◽  
Henner Simianer ◽  
Torsten Pook
Keyword(s):  
Osteochondrosis Dissecans ◽  
Selection Index ◽  
R Package ◽  
Breeding Value ◽  
Index Selection ◽  
Threshold Selection ◽  
Horse Breeding ◽  
Frequency Of Use ◽  
Performance Traits ◽  
And Performance

Osteochondrosis dissecans (OCD) is a degenerative disease of the cartilage leading to osseous fragments in the joints. It is important in horse breeding both from an animal welfare and an economic perspective. To study adequate breeding strategies to reduce OCD prevalence, a lifelike simulation of the breeding program of German Warmblood horses was performed with the R package MoBPS. We simulated complex breeding schemes of riding horses with different selection steps and realistic age structure, mimicking the German situation. As an example, osseous fragments in fetlock and hock joints were considered. Different scenarios, either using threshold selection, index selection or genomic index selection, respectively, were compared regarding their impact on health and performance traits. A rigorous threshold selection as well as the integration of OCD in a selection index at the stage of stallion licensing and chosen frequency of use in breeding cases on a selection index that includes breeding values for OCD traits performed best on a comparable level. Simply integrating OCD in this breeding value was less effective in terms of OCD reduction. Scenarios with a higher reduction of OCD also showed a slightly reduced improvement in the riding horse performance traits.

Genetic parameters for live weight, ultrasonic measurements and conformation in Bluefaced Leicester sheep

1999 ◽  
Vol 1999 ◽  
pp. 122-122 ◽  
Author(s):  
A.M. van Heelsum ◽  
R.M. Lewis ◽  
D.W. Jones ◽  
W. Haresign ◽  
M.H. Davies
Keyword(s):  
Selection Index ◽  
Live Weight ◽  
Carcass Quality ◽  
Export Markets ◽  
Acceptable Quality ◽  
Breeding Programmes ◽  
The Uk ◽  
Terminal Sire ◽  
Sire Breed

Currently fewer than 50% of UK lambs produce carcasses of acceptable quality for the domestic and export markets, which compromises the competitiveness of sheep farming. Carcass quality can be changed by selection, and this is now being taken advantage of in terminal sire breeds and, to a lesser extent, in hill breeds. However, little attention has yet been focused on the crossing breeds, which have relatively poor carcass quality, in spite of the large impact such breeds have on the slaughter generation. Recently, a long-term project began to develop breeding programmes relevant to crossing sire (‘longwool’) breeds. Its objective is to produce a selection index to improve carcass quality without compromising the reproductive performance or maternal ability of these breeds. The Bluefaced Leicester is the most prevalent crossing sire breed with its crossbred (‘Mule’) daughters out of draft hill ewes accounting for 89% of crossbred (longwool x hill) ewes in the UK (Pollot, 1998).

Selection indices for terminal sires to improve lean meat production from sheep in the United Kingdom

1987 ◽  
Vol 45 (1) ◽  
pp. 87-96 ◽  
Author(s):  
A. C. Parratt ◽  
G. Simm
Keyword(s):  
Growth Rate ◽  
Carcass Composition ◽  
Breeding Value ◽  
Meat Production ◽  
Lean Meat ◽  
The United Kingdom ◽  
Ct Measurements ◽  
Selection Indices ◽  
Efficiency Of Selection ◽  
Terminal Sire

AbstractSelection indices to improve lean meat production of terminal sire breeds of sheep were derived. An aggregate breeding value which comprised growth rate, killing-out proportion and carcass lean proportion was examined. Selection criteria included growth rate and ultrasonic or X-ray computer tomography (CT) estimates of carcass composition. Correlations betwen the index and the aggregate breeding value were about 0·38 for indices using ultrasonic fat measurements, and about 0·40 for those using CT measurements. Dropping ultrasonic or CT measurements from the indices reduced the correlations with the aggregate breeding value by only about 0·01 and 002 respectively, indicating that selection on growth rate alone under current economic conditions was highly efficient. Changes in economic weights, and genetic parameters had little effect on the efficiency of selection. The total national discounted value of returns from a single round of selection on the indices was expected to be between £6 and £30·5 million, depending on penetration rates of improved stock, the breeding scheme used, and with a time horizon of 20 years.

scholarly journals Ultrasonic Carcass Assessment of Dorper and Dorper x Merino Lambs Using MLD and Body Measurements

2016 ◽  
Vol 4 (5) ◽  
pp. 395 ◽  
Author(s):  
Onur Yılmaz ◽  
Sezen Ocak ◽  
Sinan Ogun
Keyword(s):  
Body Length ◽  
Selection Index ◽  
Live Weight ◽  
Least Square ◽  
Backfat Thickness ◽  
Meat Production ◽  
Dry Land ◽  
Thickness Skin ◽  
Ultrasonic Measurements ◽  
Effective Selection

Ultrasonic measurements of Musculus longissmus dorsi thoracis et lumborum (MLD) were taken of Dorper (n=99) and Dorper x Merino (n=65) lambs at 156 days of age and comparisons made to various body dimensions to ascertain whether sex, genotype, birth type and live weight had any effect on these parameters. Lambs were weaned two months after birth and placed ad libitum on basic dry land pasture during the draught spring and summer months of 2014 in the arid southeastern region of Turkey. Least square means of backfat thickness, skin+backfat thickness, muscle depth, body length, chest girth and live weight, at the mean age of 156 days, were 0.17 cm, 0.32 cm, 1.75 cm, 63.30 cm, 72.37 cm and 25.16 kg, respectively. Genotype was a statistically significant factor in terms of back fat thickness (BFT), skin and backfat thickness (S+BFT), muscle depth (MD), body length (BL) and live weight (LW). The study showed that Dorper and Dorper x Merino genotypes into Turkey show a clear advantage over the native breeds in terms of meat production and quality not to mention the high potential for lean carcass production. Ultrasonic measurements of Longissimus thoracis et lumborum (MLD) will provide an important contribution to selection index in breeding programs for Dorper and Dorper crossbred genotypes. However estimation of genetic parameters are required in containing a pedigree database in order to establish an effective selection index.

Genetic parameters of lamb carcase composition at three endpoints; age, weight and fat cover.

1993 ◽  
Vol 1993 ◽  
pp. 104-104
Author(s):  
G.E. Pollott ◽  
D.R. Guy ◽  
D. Croston
Keyword(s):  
Genetic Parameters ◽  
Common Point ◽  
Breeding Value ◽  
Meat Production ◽  
Lean Meat ◽  
Fixed Weight ◽  
Breeding Programmes ◽  
The Common ◽  
Terminal Sire ◽  
The Relationship

The common point at which lambs are compared is an important aspect of selection programmes for lamb carcase composition. Terminal sire flocks in the Meat and Livestock Commission's (MLC) Sheepbreeder scheme have an estimated breeding value for lean meat production calculated on their lambs at a fixed age, 20 or 21 weeks depending on the breed. However, lambs sold for slaughter from commercial flocks are killed at a commercially acceptable fat cover. In addition, many of the estimates of genetic parameters used to estimate breeding values for carcase characteristics have been calculated at a fixed weight. Little information is available on the relationship between genetic parameters calculated at these three endpoints or the effect of selecting lambs at one endpoint in breeding programmes and using a second endpoint for the slaughter generation. These issues are investigated in this paper.

scholarly journals RESULTS OF BREEDING VALUE EVALUATION OF SOWS WITH THE USE OF TRADITIONAL AND INNOVATIVE METHODS

2020 ◽  
pp. 212-224
Author(s):  
V.I. Khalak ◽  
V.S. Kozir ◽  
Yevhen Rudenko
Keyword(s):  
Economic Efficiency ◽  
Selection Index ◽  
Pair Correlation ◽  
Live Weight ◽  
Animal Husbandry ◽  
Organic Production ◽  
Breeding Value ◽  
High Fertility ◽  
Industrial Complex ◽  
Research Results

The article presents the results of research on the reproductive qualities of sows of different breeding value, as well as determines the economic efficiency of their use in the industrial complex. The study was conducted in agricultural formations of the Dnipropetrovsk region (LLC "Druzhba-Kaznacheyivka", LLC "Vidrodzhennia") and the laboratory of animal husbandry of the State Institution Institute of Grain Crops NAAS. The work was performed according to the research program of NAAS №30 "Innovative technologies of breeding, industrial and organic production of pig products" ("Pig breeding"). Evaluation of sows on the grounds of reproductive qualities was carried out taking into account the following indicators: fertility, head; high fertility, kg, number of piglets at weaning, head, nest weight at the time of weaning at the age of 28 days, kg, nest weight at the time of weaning at the age of 60 days (estimated), kg, safety, %. The breeding value of animals was determined by the multiplicity and weight of the nest at the time of weaning (according to Annex 7 of the Instructions for grading pigs) and the selection index of reproductive qualities of sows (SIVYAS). The index of alignment (homogeneity) of the sow's nest by live weight of piglets at the time of their birth (ІВГ0) was calculated according to the method of V.I. Khalak (2012), the economic efficiency of research results - according to conventional methods. Biometric processing of research results was performed according to the methods of G.F. Lakin (1990). It was found that sows of the "elite" class were superior to peers of the "extracurricular" class in terms of multiplicity, several piglets at weaning, nest weight at weaning at 28 days and nest weight at weaning at 60 days (estimated) by an average of 28, 76%. The difference between sows of classes M + and M- (distribution class for SIVYAS) in terms of multiplicity, number of piglets at the time of weaning, the weight of the nest at the time of weaning at the age of 28 days and weight of the nest at the time of weaning at the age of 60 days (estimated) is 34.32. 34.78, 27.60 and 28.30 %, respectively. The coefficients of pair correlation between the absolute indicators of reproductive qualities of sows, the index "alignment (homogeneity) of the sow's nest by live weight of piglets at birth" and the selection index of reproductive qualities of sows (SIVYAS) at 83.33-100.0 % are reliable from -0.446 to +0.989. The criterion for the selection of highly productive animals according to the Instructions for grading pigs is the class "elite", according to the selection index of reproductive qualities of sows (SIVYAS) - 97.85-123.99 and more points. The use of sows of the class "elite" and М+ (according to SIVYAS) provides additional products at the level of +11.84 - 16.49 %.

Attainment of puberty and response to superovulation in performance-tested Simmental heifers

1996 ◽  
Vol 63 (1) ◽  
pp. 65-71 ◽  
Author(s):  
L. D. Tregaskes ◽  
P. J. Broadbent ◽  
J. S. M. Hutchinson ◽  
J. A. Roden ◽  
D. F. Dolman
Keyword(s):  
Weight Gain ◽  
Performance Test ◽  
Selection Index ◽  
Live Weight ◽  
Metabolizable Energy ◽  
Breeding Value ◽  
Reproductive Maturity ◽  
Live Weight Gain ◽  
Embryo Recovery ◽  
Age At Puberty

AbstractPuberty during performance test and the effect of reproductive maturity and performance on test on superovulatory response were investigated using Simmental heifers.Three generations of Simmental heifers (no. = 110) were performance tested for beef characteristics between 23 and 49 weeks of age over 3 years successively. Embryo recoveries were performed at 52 and 61 weeks of age following the end of the performance test. The onset of puberty was observed in 26 of 30 (87%) heifers in the 3rd year. The mean age at puberty was 284·7 (s.e. 6·63) days. Age at puberty was not significantly related to daily live-weight gain (1·5 (s.e. 0·02) kg) up to the onset of puberty. Heifers experienced zero to six oestrous cycles before initiation of the first superovulatory treatments. There was a non-significant tendency (P > 0·05) for heifers that were not cyclic to produce the highest yields of viable and grade 1 embryos at the first embryo recovery.Performance test characteristics recorded were: total food intake (1604·0 (s.e. 13·2) kg), total energy intake (1852·0 (s.e. 169·0) MJ metabolizable energy) and live-weight gain (263·9 (s.e. 2·2) kg) during test; live weight (486·5 (s.e. 31·5) kg), backfat depth (5·6 (s.e. 15) mm) and muscle score (9·6 (s.e. 0·10) units) at the end of test and estimated breeding value for the selection index (+£7·00 (s.e. 0·76)). These were used as independent variables in general linear models to study their relationship with various measures of superovulatory response. Recovery rate of ova and embryos; and the yields of viable and grade 1 embryos were not related to any aspects of performance on test.In conclusion, superovulation and embryo recovery were affected by reproductive maturity at the time of gonadotropin treatment and these procedures may be more effective in juvenile heifers before the establishment of cyclicity. Embryo production from 12- to 15-month-old Simmental heifers following a beef performance test was not related to their performance on test.

The consequences of index selection on carcass composition in Suffolk sheep

1999 ◽  
Vol 1999 ◽  
pp. 46-46 ◽  
Author(s):  
R. M. Lewis ◽  
G. C. Emmans ◽  
G. Simm ◽  
W. S. Dingwall ◽  
J. FitzSimons ◽  
...  
Keyword(s):  
Performance Test ◽  
Selection Index ◽  
Live Weight ◽  
Growth Index ◽  
Carcass Composition ◽  
Control Line ◽  
Lean Growth ◽  
Selection Decisions ◽  
Terminal Sire ◽  
And Control

Early in the 1980s a selection index was designed at SAC to improve the rate of lean growth in terminal sire sheep which combined ultrasound measurements of fat and muscle depth, and live weight at 150 days of age (Simm and Dingwall, 1989). Beginning in 1985, this index was applied in the SAC Suffolk flock in a performance test. In 1994, rams from a line selected on this index weighed on average 12% more (8 kg) and had 12% lower fat depth (– 0.9 mm) and 10% higher muscle depth (2.9 mm) than rams from an unselected Control line. Comparison of Selection and Control line animals has thus far been based on live predictors of carcass composition at weights substantially heavier than typical market lamb weights. The aims of this study were to test whether selection decisions based on the lean growth index produced an improvement in actual carcass composition in purebred terminal sire sheep and whether these changes persisted at live weights different from those under which selection was carried out.

Selection for carcass lean content in a terminal sire breed of sheep

1992 ◽  
Vol 54 (3) ◽  
pp. 367-377 ◽  
Author(s):  
N. D. Cameron ◽  
J. Bracken
Keyword(s):  
Selection Index ◽  
Selection Criterion ◽  
Live Weight ◽  
Residual Maximum Likelihood ◽  
Cumulative Response ◽  
Cumulative Selection ◽  
Selection For ◽  
The Difference ◽  
Terminal Sire ◽  
Sire Breed

AbstractA divergent selection experiment for carcass leanness in Texel-Oxford sheep was established to examine the differences between genetically lean and fat animals derived from the same base population. The selection criterion was designed to change body composition without a corresponding change in live weight, using an index of ultrasonic backfat depth and live weight at 20 weeks of age. The index was constructed using estimates of genetic and phenotypic parameters, which were available at the start of the experiment in 1985. The difference between the high and low lines, after 3 years of selection, for the selection index, live weight at 20 weeks of age, ultrasonic backfat and muscle depths was 0·59,1·30 kg, -0·76 mm and 0·88 mm respectively. The estimated difference for carcass lean and fat weight was 0·72 kg and -0·04 kg respectively with 13·5 g/kg and -13·8 g/kg for carcass lean and fat proportion. The realized heritability for the selection index, estimated from the regression of cumulative response on cumulative selection differential was 0·42, with a standard error of 0·25, after taking account of genetic drift. The selection index heritability, estimated with residual maximum likelihood (REML) methodology, was 0·46 (s.e. 0·14). REML heritability estimates for live weight at 20 weeks of age, ultrasonic backfat and muscle depths were 0·20 (s.e. 0·13), 0·35 (s.e. 0·14) and 0·43 (s.e. 0·14) respectively.

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