Skin wrinkles of the sire adversely affect Merino and halfbred pelt characteristics and other production traits

2005 ◽  
Vol 45 (12) ◽  
pp. 1551 ◽  
Author(s):  
D. R. Scobie ◽  
S. R. Young ◽  
D. O'Connell ◽  
E. Eythorsdottir
Keyword(s):  
Standard Deviation ◽  
Fibre Diameter ◽  
Production Traits ◽  
Merino Sheep ◽  
Leather Processing ◽  
Breed Differences ◽  
Wool Quality ◽  
Skin Wrinkles ◽  
Staple Length

The wrinkles on the skin of Merino sheep and related breeds are retained during leather processing, and the skins are known as ‘ribby pelts’ in the leather trade. Merino sires with either no skin wrinkles (smooth, n = 7) or excessive wrinkles (ribby, n = 7) were allocated at random to mating groups of 22 Merino ewes mixed with 22 Romney ewes. The progeny of ribby sires were more ribby at docking (P<0.001), at shearing (P<0.001), in the fellmongery (P = 0.001) and as pickled pelts (P<0.001). Merino progeny were more ribby than Merino × Romney (halfbred) progeny at all stages. When professionally graded as pickled pelts, smooth-sired progeny produced more pelts without ribs in both Merino (5% v. 0%) and halfbreds (69% v. 38%) than ribby-sired progeny. Wool samples collected at 7.5 months of age were not significantly different between sire groups in mean fibre diameter (P = 0.27) or staple length (P = 0.60) but they were different in standard deviation of fibre diameter (P = 0.003). Liveweight was consistently greater in the progeny of smooth sires, although this difference did not reach significance until the progeny attained a mean liveweight of 28 kg for Merinos and 32 kg for halfbreds (P = 0.016). Breed differences were observed in other traits and these are discussed. Interestingly, there were few significant sire type breed interactions, the exceptions being yield of clean wool (P<0.001), standard deviation of fibre diameter (P = 0.003) and an additional pelt trait referred to as pinhole score (P = 0.003). In summary, choosing sires without skin wrinkles can improve pelt quality, wool quality and liveweight of Merino and halfbred progeny.

Genetic parameters for visually assessed traits and their relationships to wool production and liveweight in Australian Merino sheep

2009 ◽  
Vol 49 (1) ◽  
pp. 32 ◽  
Author(s):  
S. I. Mortimer ◽  
D. L. Robinson ◽  
K. D. Atkins ◽  
F. D. Brien ◽  
A. A. Swan ◽  
...  
Keyword(s):  
Coefficient Of Variation ◽  
Genetic Correlations ◽  
Fibre Diameter ◽  
Quality Traits ◽  
Production Traits ◽  
Merino Sheep ◽  
Wool Production ◽  
Breeding Objectives ◽  
Wool Quality ◽  
Staple Length

Heritability was estimated for a range of visually assessed traits recorded on Merino sheep, together with the phenotypic and genetic correlations among the visually assessed traits and correlations of the visually assessed traits with measured wool production traits and liveweight. Data were derived from four research resource flocks, with a range of 12 958 to 57 128 records from animals with 478 to 1491 sires for the various traits. The estimates of heritability were high for the wool quality traits of handle, wool character and wool colour (0.33–0.34) and the conformation traits of face cover, neck wrinkle and body wrinkle (0.42–0.45), moderate for front leg structure (0.18) and low for back leg structure (0.13). Fleece rot score had low heritability (0.14), while classer grade was moderately heritable (0.20). Estimates of genetic correlations among the visually assessed wool quality traits were low to moderate in size and positive (0.17–0.47). Genetic correlation estimates among the assessed conformation traits were generally very low, except for the genetic correlations between scores for neck and body wrinkle (0.92 ± 0.01) and front and back leg structure (0.31 ± 0.09). Fleece rot score had low positive genetic correlations with neck and body wrinkle scores (0.18 ± 0.05 and 0.15 ± 0.05, respectively) and classer grade (0.26 ± 0.06). Classer grade was slightly positively correlated with the wool quality traits (0.17–0.45) and leg structure traits (0.21–0.25). The genetic correlations among the visually assessed traits were generally neutral to favourable. The visually assessed wool quality traits had low to moderate favourable genetic correlations with mean and coefficient of variation of fibre diameter (0.19 –0.47), but negative correlations with clean wool yield (–0.26 to –0.37). Face cover was unfavourably correlated with staple length (–0.27 ± 0.04) and liveweight (–0.23 ± 0.02). Neck and body wrinkle scores were genetically associated with higher greasy (0.33–0.39) and clean fleece weights (0.19–0.22), greater coefficient of variation of fibre diameter (0.24–0.26) and fibre curvature (0.27–0.28), but with reduced yield (–0.26 to –0.28) and staple length (–0.34 to –0.41). Fleece rot score was genetically correlated with clean fleece weight (0.26 ± 0.05) and coefficient of variation of fibre diameter (0.27 ± 0.04). Classer grade was favourably correlated with greasy and clean fleece weights (–0.41 to –0.43), staple length (–0.29 ± 0.04), liveweight (–0.36 ± 0.03) and coefficient of variation of fibre diameter (0.27 ± 0.03). Most genetic correlations between the visually assessed traits and the measured production traits and liveweight were close to zero and less than 0.2 in magnitude. This study provides accurate values for the parameter matrix required to incorporate visually assessed traits into breeding objectives and the genetic evaluation programs used in the Australian sheep industry, allowing the development of breeding objectives and indexes that optimally combine visually assessed performance and measured production in Merino sheep.

Comparison of estimates of repeatability and heritability for some production traits in Merino rams and ewes. 2. Heritability

1960 ◽  
Vol 11 (4) ◽  
pp. 604 ◽  
Author(s):  
SSY Young ◽  
Turner H Newton ◽  
CHS Dolling
Keyword(s):  
Body Weight ◽  
Population Density ◽  
Sex Difference ◽  
Fibre Diameter ◽  
Production Traits ◽  
Merino Sheep ◽  
Lower Figure ◽  
Selection Of ◽  
Australian Merino ◽  
Staple Length

Heritability estimates were calculated for 10 traits in rams and ewes of a medium-woolled strain of Australian Merino sheep. The traits were greasy wool weight, clean scoured yield, clean wool weight, body weight, wrinkle score, face cover score, fibre population density, fibre diameter, staple length, and crimps per inch. Estimates were made by dam-offspring correlations, measurement on the dams being at 15-16 months, on daughters at 15-16 months, and on sons at both 10-12 and 15-16 months. All estimates for both sexes lay between 0.3 and 0.6, except for fibre population density (0.24) and fibre diameter (0.12) in rams at 15-16 months and for clean wool weight (0.29) and face cover score (0.29) in rams at 10-12 months. The only significant sex difference lay in the lower figure for fibre diameter in rams at 15-16 months, but this is of doubtful importance as the corresponding figure for rams at 10-12 months (0.37) did not differ significantly from the ewe figure. All traits may be considered highly heritable, and the high values for the yearling rams indicate that consideration might be given to the selection of rams for production traits at an earlier age than the traditional one of 18 months or older.

Genetic studies of South Australian Merino sheep. 3. Heritabilities of various wool and body traits

1982 ◽  
Vol 33 (2) ◽  
pp. 355 ◽  
Author(s):  
IP Gregory
Keyword(s):  
Body Weight ◽  
Fibre Diameter ◽  
Skin Thickness ◽  
Production Traits ◽  
Primary Follicle ◽  
Merino Sheep ◽  
Main Production ◽  
Fleece Weight ◽  
Australian Merino ◽  
Staple Length

Heritabilities have been estimated for a large number of quantitative and qualitative wool and body traits recorded on two flocks of South Australian Merino sheep over a 12-year period. Data were unadjusted for fixed environmental effects and so the estimates are applicable to the heterogeneous populations found in most practical situations. Dam-offspring heritabilities of quantitative traits ranged from 0.15 for primary follicle number to 0.63 for body weight. Greasy and clean fleece weights, percentage clean yield, staple length, crimps per inch, fibre diameter, secondary and total follicle number, skin thickness, coefficient of variation of fibre diameter and secondary/primary follicle ratio had moderate to high heritabilities. Dam-offspring heritabilities of qualitative traits ranged from 0.12 for weather damage of the fleece to 0.75 for birthcoat. Total folds, face cover and hocks had high heritabilities, and wool character, type of staple formation and wool quality had moderate heritabilities. The main production traits (body weight, greasy fleece weight, yield, clean fleece weight, staple length, fibre diameter and total follicle number) were corrected for variation due to type of birth and age of dam and their heritabilities re-estimated. No change occurred in the half-sib heritabilities; dam-offspring heritabilities increased by an average of 0.05.

Effects of site of assessment and variation in wool quality traits on the tactile assessment of textural greasy wool handle

2014 ◽  
Vol 54 (10) ◽  
pp. 1665 ◽  
Author(s):  
J. W. V. Preston ◽  
S. Hatcher ◽  
B. A. McGregor
Keyword(s):  
Fibre Diameter ◽  
Quality Traits ◽  
Merino Sheep ◽  
Diameter Fibre ◽  
Wool Quality ◽  
A Site ◽  
Staple Length

Variation in textural greasy wool handle across the fleece of Merino sheep was explored. Results demonstrate that there were significant differences across nine sites on the fleece. The inclusion of the covariates fibre diameter, fibre diameter co-efficient of variation, staple length, dust penetration, staple structure, greasy wool colour and resistance to compression, helped to explain some of the variation in textural greasy wool handle between sites such that site of assessment was no longer a significant factor (P = 0.065). However, in practice, those involved with clip preparation or sheep selection based on textural greasy wool handle assessment are unlikely to have these measurements available. The results highlight the importance of nominating a site of assessment when recording textural greasy wool handle.

scholarly journals LAMB AND WOOL PRODUCTION FROM FIVE BREEDS ON RANGE

1966 ◽  
Vol 46 (1) ◽  
pp. 9-18 ◽  
Author(s):  
J. A. Vesely ◽  
H. F. Peters ◽  
S. B. Slen
Keyword(s):  
Body Weight ◽  
The Other ◽  
Production Traits ◽  
Weaning Weight ◽  
Wool Production ◽  
Breed Differences ◽  
Percentage Yield ◽  
Ewe Lamb ◽  
Fleece Weight ◽  
Staple Length

Rambouillet, Romnelet, Columbia, Targhee, and Suffolk sheep were evaluated under range conditions for the production of lamb and wool in the period 1960–1963. The production traits analyzed were: birth and weaning weight; face cover and neck wrinkling; fertility, prolificacy, weaned lamb production, and body weight of ewe; lamb survival to weaning; grease and clean fleece weight, staple length, wool grade, and percentage yield of clean wool by yearling and mature ewes.Lambs of Romnelet were lighter at birth than those of the other breeds. Targhee and Suffolk were the heaviest at birth. Romnelet and Columbia lambs were lighter at weaning than those of Rambouillet, Targhee, and Suffolk.Fertility, prolificacy, and weaned lamb production were essentially the same in the four range breeds. Suffolk produced more weaned lamb than the other four breeds. There were no breed differences in the survival of lambs.Columbia exceeded all other breeds in production of grease and clean fleece weight. Suffolk produced the smallest amount of wool. Staple length of Columbia ewes was 4.3, 7.5, 18.6, 23.7 mm longer than that of Romnelet, Targhee, Suffolk, and Rambouillet ewes.

Genetic and phenotypic parameters for reproduction, production and bodyweight traits in Australian fine-wool Merino sheep

2018 ◽  
Vol 58 (2) ◽  
pp. 207 ◽  
Author(s):  
S. Dominik ◽  
A. A. Swan
Keyword(s):  
Genetic Relationships ◽  
Genetic Correlations ◽  
Fibre Diameter ◽  
Careful Consideration ◽  
Production Traits ◽  
Merino Sheep ◽  
Wool Production ◽  
Phenotypic Correlations ◽  
Reproduction Traits ◽  
Definition Of

The present study estimated phenotypic and genetic relationships between wool production, reproduction and bodyweight traits in Australian fine-wool Merino sheep. The data for the study originated from the CSIRO Fine Wool Project, Armidale, Australia. Data on wool characteristics, measured at ~10 and 22 months of age, bodyweight and several reproduction traits across consecutive lambing opportunities were analysed. The genetic correlations were moderately negative between fibre diameter measured as yearling and adult, and lamb survival (rg = –0.34 ± 0.15 and rg = –0.28 ± 0.14 respectively) and total number of lambs weaned (rg = –0.32 ± 0.21 and rg = –0.40 ± 0.21 respectively). The genetic correlations of yearling and adult greasy and clean fleece weights with number of lambs weaned and fecundity showed moderately to highly negative relationships and a moderately negative correlation with the number of fetuses at pregnancy scanning. Phenotypic correlations between reproduction and wool production traits were estimated to be zero, with the exception of bodyweight showing low to moderate positive phenotypic correlations with total number of lambs born and weaned. Genetic variances were generally low for the reproduction traits and resulted in low heritability estimates (from h2 = 0.03 ± 0.01 to h2 = 0.12 ± 0.13), with the exception of total number of lambs born (h2 = 0.25 ± 0.03). The study indicated that parameter estimation and trait definition of lifetime reproduction records require careful consideration and more work in this area is required.

Effect of stocking rate on fleece measurements and their relationships in merino sheep

1976 ◽  
Vol 27 (1) ◽  
pp. 163 ◽  
Author(s):  
DH White ◽  
BJ McConchie
Keyword(s):  
Fibre Diameter ◽  
Major Determinant ◽  
Stocking Rate ◽  
Merino Sheep ◽  
Wool Production ◽  
Rate Experiment ◽  
Fleece Weight ◽  
One Year ◽  
Staple Length

The wool characteristics of Merino wethers were measured for 6 years in a stocking rate experiment. The decline in fleece weight due to increasing stocking rate from 4.9 to 12.4 sheep per hectare was usually accompanied by a reduction in fibre diameter and staple length and an increase in staple crimp frequency. The magnitude of these responses differed considerably between years; in one year clean fleece weight was reduced by 50%, with an associated reduction of 5 µm in mean fibre diameter and one of 2 cm in staple length. In four of the six years of the experiment, variation in fibre diameter accounted for at least 50% of the variation in wool production between stocking rate treatments. The relationships between clean fleece weight and fibre diameter were similar between years, mean fibre diameter being reduced by about 1.8 �m for each kilogram reduction in clean fleece weight. Fibre diameter is the major determinant of wool price, and this information should improve the prediction of economic responses to changes in stocking rate.

Environmental influence on Merino sheep wool quality through the lens of seasonal variations in fibre diameter

2020 ◽  
Vol 181 ◽  
pp. 104248
Author(s):  
Ezequiel Bernardo Gonzalez ◽  
Diego Mariano Sacchero ◽  
Marcos Horacio Easdale
Keyword(s):  
Seasonal Variations ◽  
Environmental Influence ◽  
Fibre Diameter ◽  
Merino Sheep ◽  
Wool Quality ◽  
Sheep Wool

The relationship of lamb birthcoat to adult fleece structure in a strain of Merino sheep

1958 ◽  
Vol 9 (4) ◽  
pp. 567 ◽  
Author(s):  
PG Schinckel
Keyword(s):  
Body Weight ◽  
Fibre Diameter ◽  
Merino Sheep ◽  
Gene System ◽  
Weight Yield ◽  
Fleece Weight ◽  
Relationship Of ◽  
The Relationship ◽  
Staple Length

Variability of the lamb birthcoat has been studied in relation to adult fleece characteristics. Coarse birthcoats were associated with increased variability of fibre diameter and decreased crimp rate. The increased variability of fibre diameter resulted from a significant increase in the diameter of primary fibres and a small, but statistically non-significant, decrease in the diameter of secondary fibres. There was no relation between birthcoat grade and body weight, clean fleece weight, yield, staple length, follicle density, follicle ratio, mean fibre diameter, or skin folds. It is postulated that there is a gene system in the Merino the effect of which is to cause variation in the amount of wool produced by the different follicle types. Increased "dosage" of genes of the system endows primary follicles with increased productivity and secondary follicles with decreased productivity. This is expressed in the form of increased halo-hair abundance in the lamb and increased differences between the diameters of primary and secondary fibres in the adult.

The study of variability in some wool traits in a coarse wool breed of sheep

1973 ◽  
Vol 80 (2) ◽  
pp. 233-238 ◽  
Author(s):  
R. A. Guirgis
Keyword(s):  
Statistical Analysis ◽  
Standard Deviation ◽  
Major Part ◽  
Fibre Diameter ◽  
Coefficient Of Determination ◽  
Main Contributor ◽  
Total Variability ◽  
The Mean ◽  
Staple Length

SummaryWool samples from 47 Barki yearlings were taken from five positions during two years to study the variability in the fleece, the cause of variability and associations between different fleece traits. Statistical analysis has indicated the following significant points.An antero-posterior gradient occurred in the different traits under study. When medullation was discarded, though it was of a low magnitude (3·9%), a reduction of 5·89% in the mean fibre diameter and of 18·33% in its standard deviation occurred.The position most representative of the whole fleece varied with the trait. It is recommended to take three sampling positions forming a triangle, withers, mid-side and hip, to represent the Barki fleece.The animals contributed the major part in the variability of mean fibre diameter (1), the standard deviation of fibre diameter (S.D.1), percentage medullation, mean fibre diameter after discarding the medullated fibres (2), the standard deviation of fibre diameter after discarding the medullated fibres (S.D.2), the contribution of medullation to the total variability, percentage fine fibres and percentage coarse fibres. The positions were the main contributor to the variability of percentage kemp fibres, staple length, medullation index and to a certain extent to that of the kemp score. The year played a significant part in the variability except for 2 and S.D.2.The highest correlations with the standard deviation of fibre diameter were those of percentage medullation and kemp score. These three variables when considered separately accounted for 0·47, 0·35 and 0·31 respectively of the variability in S.D.Equations were obtained to predict the standard deviation from both the mean fibre diameter and the percentage medullation and to predict the mean fibre diameter from the staple length and the kemp score. The coefficient of determination of the first set of equations ranged from 0·47 to 0·56 while that of the second set ranged between 0·07 and 0·51 for different positions.

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