Differences in fibre diameter profile characteristics in wool staples from Merino sheep and their relationship with staple strength between years, environments, and bloodlines

2002 ◽  
Vol 53 (4) ◽  
pp. 481 ◽  
Author(s):  
D. J. Brown ◽  
B. J. Crook ◽  
I. W. Purvis
Keyword(s):  
Fibre Diameter ◽  
Alternative Interpretation ◽  
Merino Sheep ◽  
Explanatory Variables ◽  
Diameter Variation ◽  
Diameter Fibre ◽  
Staple Strength ◽  
Profile Characteristics ◽  
Diameter Change ◽  
Staple Length

This study examined differences in fibre diameter profiles (FDPs) and midside characteristics of Merino sheep in 2 environments, 4 bloodlines, 3 years, and 44 sire groups. Environment significantly (P < 0.05) influenced all characteristics except one measure of fibre diameter change and staple length. Bloodline also significantly (P < 0.05) influenced all characteristics except staple strength. The maximum fibre diameter, one measure of fibre diameter change, and staple length were significantly different (P < 0.05) between sires. Variation in fibre diameter profile characteristics between bloodlines and sires changed across the environment in which the sheep are maintained. Despite these differences between bloodlines and sires in the FDP, midside mean fibre diameter, fibre diameter variation, and staple length, there were no significant differences between bloodlines in staple strength. The relationships between the FDP and midside characteristics with staple strength were also examined over these bloodlines and environments. Along-staple variation in fibre diameter (r = –0.32 to –0.50), between-fibre fibre diameter variation (r = –0.25 to –0.48), rate of fibre diameter change (r = –0.16 to –0.38), and midside variation in fibre diameter (r = –0.25 to –0.51) were all negatively correlated with staple strength. Maximum fibre diameter (r = 0.08 to 0.18), minimum fibre diameter (r = 0.25 to 0.49), and midside mean fibre diameter (r = 0.09 to 0.35) were positively associated with staple strength. FDP characteristics explained 5–30% more variation in staple strength than could be explained using the standard midside characteristics of mean fibre diameter, fibre diameter variation, and staple length alone. These relationships were also different between environments and bloodlines. The inclusion of the FDP characteristics as explanatory variables provided an alternative interpretation for how absolute fibre diameter and fibre diameter variation combine to explain staple strength. These results suggested that animals and sires might be able to be selected on FDP characteristics to improve staple strength. More detailed genetic studies are required before these selection strategies can be recommended.

Environmental responsiveness of fibre diameter in grazing fine wool Merino sheep

2005 ◽  
Vol 56 (7) ◽  
pp. 673 ◽  
Author(s):  
D. J. Brown ◽  
B. J. Crook
Keyword(s):  
Seasonal Variation ◽  
Fibre Diameter ◽  
Fibre Length ◽  
Skin Thickness ◽  
Merino Sheep ◽  
Length Growth ◽  
Environmental Responsiveness ◽  
Diameter Fibre ◽  
Staple Strength ◽  
Profile Characteristics

Fibre diameter, fibre length, and the ratio of fibre length growth to mean fibre diameter (L/D), fibre diameter profile characteristics, and staple strength were examined in 16 fine wool Merino wethers in a 12-month field experiment. Variations in fibre diameter, fibre length, and L/D were shown to be associated with fibre diameter profile characteristics and staple strength. At constant fibre diameter, L/D was significantly positively related to variation in fibre diameter along the staple. A positive correlation between seasonal variation in L/D and variation in diameter between fibres was also observed. Staple length was significantly positively correlated with along-staple variation in fibre diameter and negatively correlated with variation in fibre diameter among fibres. Among-fibre variation in fibre diameter was not significantly correlated with along-staple variation in fibre diameter. Seasonal variation in fibre length growth, fibre diameter, and the ratio of length to diameter throughout the year was associated with increased variation in fibre diameter along the fibre diameter profile and reduced staple strength in grazing sheep. Seasonal variation in fibre diameter was mostly related to mean fibre diameter, L/D, and seasonal variation in fibre length growth rate. Changes in fibre diameter throughout the year were also related to seasonal changes in body weight, fat depth, and skin thickness.

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.

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.

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.

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.

Inheritance of Acid Red 1 dye absorption and its relationship to other Merino wool traits

2006 ◽  
Vol 46 (7) ◽  
pp. 943 ◽  
Author(s):  
A. C. Schlink ◽  
S. Ortega ◽  
J. C. Greeff ◽  
M. E. Dowling
Keyword(s):  
Coefficient Of Variation ◽  
Fibre Diameter ◽  
Merino Wool ◽  
Dyeing Performance ◽  
Dye Absorption ◽  
High Heritability ◽  
Acid Red 1 ◽  
Staple Strength ◽  
Wool Dyeing ◽  
Staple Length

Optimising and ensuring the reproducibility of wool dyeing is of significant economic importance to the wool industry. Midside wool from 1824 Merino ewe and ram hoggets was used to estimate the heritability of Acid Red 1 dye absorption in clean wool. Acid Red 1 absorption had a high heritability of 0.45 ± 0.07 and was phenotypically poorly correlated with fibre diameter (–0.11 ± 0.03), the coefficient of variation of fibre diameter (0.05 ± 0.03), curvature (–0.05 ± 0.03), staple strength (–0.02 ± 0.02) and staple length (–0.09 ± 0.03), yield (0.08 ± 0.03) and dust penetration (0.07 ± 0.03). It was not genetically correlated with fibre diameter (–0.05 ± 0.09), the coefficient of variation of fibre diameter (0.02 ± 0.09), curvature (–0.09 ± 0.09), staple strength (–0.07 ± 0.10) or staple length (–0.03 ± 0.08), but weakly genetically correlated with yield (0.18 ± 0.08) and dust penetration (0.24 ± 0.12). Dye absorption was also genetically negatively correlated with wool felting as measured by feltball diameter (–0.26 ± 0.09). Acid Red 1 absorption was not genetically correlated with absorption of the cationic dye Methylene Blue. We suggest that there is a biological basis for differences between wools in dyeing performance and that this variation will depend on the class of dye being evaluated for wool dyeing.

Supplementation of young sheep with lupins plus sulfur and a complete mineral mix

1992 ◽  
Vol 32 (3) ◽  
pp. 267
Author(s):  
PT Doyle ◽  
RA Love ◽  
RH Dunlop ◽  
CL White
Keyword(s):  
Fibre Diameter ◽  
Potassium Sulfate ◽  
Feeding Period ◽  
Merino Sheep ◽  
Mineral Supplements ◽  
Wool Growth ◽  
Average Intake ◽  
Staple Strength ◽  
Fleece Weight ◽  
Mineral Lick

Young Merino sheep (7-8 months of age, weighing about 40.5 kg) were given weekly supplements of 1050 gfsheep of lupins, lupins coated with potassium sulfate (25 g/kg lupins), lupins and access to a mineral lick (offered at 175 g/sheep.week), or lupins coated with potassium sulfate and access to the lick. The sheep grazed an annual pasture at a stocking rate of 15 sheepha and were given the supplements between 14 December and 5 April. The amount of pasture on offer in mid December exceeded 3000 kg DMha but declined to 1500 kg DMha in late March.There were significant amounts of green feed present in December and March (>20% of pasture DM), a small amount in January, and no green feed in February. Despite this the percentage of sheep licking the minerals was over 70% in January , February; and March, with average intake being about 10 g/sheep.day. No significant differences occurred between treatments for liveweights of sheep during the feeding period or at shearing. Over the feeding period sheep lost weight at about 30 g/day. Neither the additional sulfur nor the mineral lick had any significant effects on fleece weight, mean fibre diameter of the fleece, staple length, or staple strength. Wool growth rates were not different between treatments during the feeding period. These results indicate that under good pasture conditions with some green feed available, and when lupins are supplied, responses to mineral supplements are unlikely.

Predicted responses in Merino sheep from selection combining visually assessed and measured traits

2010 ◽  
Vol 50 (10) ◽  
pp. 976 ◽  
Author(s):  
S. I. Mortimer ◽  
K. D. Atkins ◽  
S. J. Semple ◽  
N. M. Fogarty
Keyword(s):  
Fibre Diameter ◽  
Selection Combining ◽  
Breeding Programs ◽  
Dual Purpose ◽  
Merino Sheep ◽  
Merino Wool ◽  
Wool Quality ◽  
Staple Strength ◽  
Fleece Weight ◽  
Australian Merino

Visually assessed traits for wool quality and ease of management are important to Merino sheep breeders and need to be considered in breeding programs. The present study reports on the predicted correlated responses in visual traits from selection using a range of standard MERINOSELECT™ indices available for use in Australian Merino breeding programs. The effect of including a visual trait in the index is also reported. The visual scored traits were classer grade, wool quality (handle, character and colour), conformation (neck and body wrinkle, front and back leg structure) and fleece rot. The indices covered a range of micron premiums of varying emphasis on increasing fleece weight and reducing fibre diameter. The indices were for Merino wool enterprises (Merino 14%, Merino 7% and Merino 3.5%) and Merino dual purpose wool and meat enterprises (Dual Purpose 7% and Dual Purpose 3.5%). The breeding objectives for the indices included fleece weight, fibre diameter, coefficient of variation of fibre diameter, staple strength, bodyweight and reproduction. Selection over 10 years using the standard MERINOSELECT™ indices is predicted to result in a small correlated improvement in the wool quality traits and classer grade, with a slight deterioration in fleece rot score. The improvement in wool handle, character and colour are greater with those indices that have a greater emphasis on reducing fibre diameter than with those increasing fleece weight. Indices with more emphasis on increased fleece weight than on reduced fibre diameter are predicted to result in small increases in neck and body wrinkle scores and a slight deterioration in wool colour. Inclusion of classer grade, handle, character or colour provided slight extra gains in fleece weight for indices that emphasised reduced fibre diameter through increased accuracy of selection.

Cashmere production and fleece attributes associated with farm of origin, age and sex of goat in Australia

2008 ◽  
Vol 48 (8) ◽  
pp. 1090 ◽  
Author(s):  
B. A. McGregor ◽  
K. L. Butler
Keyword(s):  
Production Systems ◽  
Fibre Diameter ◽  
Minor Effect ◽  
Diameter Fibre ◽  
Proportional Increase ◽  
Fleece Weight ◽  
A Minor ◽  
On Farm ◽  
Age And Sex ◽  
Staple Length

Differences in cashmere production and fleece attributes associated with farm of origin, age and sex were quantified for commercial Australian cashmere goat enterprises. From 11 farms in four states, 1147 does and 97 wethers were monitored, representing 1- to 13-year-old goats. Individual clean cashmere production ranged from 21 to 389 g, with a mean ± standard deviation value of 134 ± 62 g. The mean cashmere production of 2-year-old does from different farms varied from 69 to 225 g and averaged 141 g. Mean ± s.d. greasy fleece weight was 394 ± 123 g, clean washing yield was 90.8 ± 4.1%, clean cashmere yield 33.4 ± 9.4%, cashmere fibre diameter 16.4 ± 1.6 µm, fibre curvature 48 ± 8.7 degrees/mm and staple length 8.7 ± 2.1 cm. There were large, commercially significant differences between farms for clean cashmere weight, mean fibre diameter and other attributes of cashmere. These were much larger than the effects of age and sex. Farm and age accounted for 42 to 67% of the variation in clean cashmere production, mean fibre diameter, fibre curvature, staple length and clean washing yield. Farm of origin affected clean cashmere yield, accounting for 24% of the variation. Sex of the goats had only a minor effect on the staple length of cashmere. The responses to age of clean cashmere weight, mean fibre diameter and the inverse of fibre curvature are very similar. Generally, cashmere production and mean fibre diameter increased with age. For the majority of farms, cashmere fibre curvature declined in a curvilinear manner with increases in age of goat. There were large differences in cashmere staple length from different farms, with means ranging from 7 to 12 cm. Between 1 and 2 years of age, the staple length of cashmere demonstrated a constant proportional increase. At ages older than 2 years, staple length either declined or increased by less than 1 cm with age, depending on the farm of origin. This study demonstrates that there are large gains in productivity that can be achieved from Australian cashmere goats. A better understanding of on-farm factors that influence cashmere production would enable all producers to optimise their production systems.

scholarly journals Evidence of a unique developmental mechanism specifying both wool follicle density and fibre size in sheep selected for single skin and fleece characters

1989 ◽  
Vol 53 (1) ◽  
pp. 57-62 ◽  
Author(s):  
G. P. M. Moore ◽  
N. Jackson ◽  
J. Lax
Keyword(s):  
Fibre Diameter ◽  
Statistical Association ◽  
Merino Sheep ◽  
Developmental Mechanism ◽  
Negative Linear Correlation ◽  
Foetal Life ◽  
Wool Follicle ◽  
Fleece Weight ◽  
The Relationship ◽  
Staple Length

SummarySkin and fleece traits have been characterized in four lines of Merino sheep selected for high- and low-fibre diameter (D±) and staple length (L±) from a medium-woolled flock. Over a period of 20 years, each line responded in the desired direction, producing fleeces composed of thick or thin fibres and long or short wool staples. However, variations in the amounts of wool grown that might be expected from these procedures were compensated by changes in unselected characters. Thus a predicted difference in fleece weights between high and low staple length lines was reduced by an increase in fibre crimp frequency in L− sheep. Similarly, changes induced in fibre diameter in the D lines resulted in small effects on fleece weight in comparison to the large (and inverse) effects on follicle numbers. Towards the end of the selection regime, mean follicle density in D− sheep was twice that of D+ sheep. This intriguing response within the follicle population was examined further: an analysis of the relationship between follicle density and fibre diameter amongst the four lines revealed a highly significant, negative linear correlation. The implication of this statistical association is that the numbers of follicles initiated in skin during foetal life had a direct bearing on the sizes of wool fibres eventually produced. It was concluded that both features must be under the control of a single developmental mechanism. Since the expression of each of the characters is separated in time, the mechanism must be activated during the earlier event, i.e. at or before the phase of follicle initiation.

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