Seasonal variation in fibre diameter and length in wool of grazing Merino sheep with low or high staple strength

1999 ◽  
Vol 39 (5) ◽  
pp. 507 ◽  
Author(s):  
A. C. Schlink ◽  
G. Mata ◽  
J. M. Lea ◽  
A. J. M. Ritchie
Keyword(s):  
Fibre Diameter ◽  
Fibre Length ◽  
Subterranean Clover ◽  
Experimental Period ◽  
Strength Group ◽  
Pooled Data ◽  
Length Growth ◽  
Fibre Growth ◽  
Staple Strength ◽  
Highly Correlated

The associations between fibre growth characteristics and wool staple strength were investigated in groups (n = 10) of Merino wethers with either low or high staple strength. Sheep grazed together on pastures based on subterranean clover and annual rye grass for about 13 months. The sheep were weighed and injected intradermally with [35 S]-cysteine at about 14-day intervals. Mid-side patches were harvested and dye bands placed in the wool at about 28-day intervals. Patch clean wool growth, pasture digestible dry matter/ha and pasture crude protein/ha had similar seasonal amplitudes of production (287, 286 and 267% of respective minimum). These were significantly higher than the seasonal amplitude in liveweight (24.5%). The seasonal amplitude in fibre diameter was significantly greater than that for rate of fibre elongation (71.4 and 41.4% respectively). This seasonality in fibre length and diameter resulted in statistically significant seasonal fluctuations in the ratio of fibre length growth to fibre diameter. Fortnightly variability in fibre diameter was not significantly related to variability in fibre length growth rate between sheep for individual time periods. However, for the pooled data over the experimental period a statistically significant relationship (R2 = 0.13, P<0.01) was improved with the addition of parameters for sampling time and staple strength group. Staple strengths for the low and high staple strength groups were 25.6 and 32.8 N/ktex respectively (P = 0.057). There were no significant differences between the staple strength groups in seasonal change in liveweight, wool production or fibre parameters measured in this study but the low staple strength group had longer fibres. Staple strength was most highly correlated with mid-side fibre diameter coefficient of variation (R2 = 0.50) followed by seasonal amplitude in liveweight.

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.

Production and quality of cashmere grown by adult wether goats fed low quality forage with supplements of either whole barley or lupin grain.

2000 ◽  
Vol 40 (6) ◽  
pp. 795 ◽  
Author(s):  
B. A. McGregor ◽  
M. Z. Umar
Keyword(s):  
Fibre Diameter ◽  
Fibre Length ◽  
Late Summer ◽  
Experimental Period ◽  
Barley Grain ◽  
Practical Application ◽  
Whole Grain ◽  
Summer Pasture ◽  
Cashmere Goats

The effects of the provision of cereal (barley) and legume (lupin) grain supplements when 50 adult wether cashmere goats were individually penned and fed on senescent temperate summer pasture (DDM 46.9%, N 0.67%, ME 6.2 MJ/kg DM) were investigated using a factorial experiment. The goats grazed senescent temperate pasture during summer before pen feeding for 9 weeks and were then grazed on germinating autumn pastures for 3 months until shorn in mid June. The production and quality of cashmere was affected by: (i) provision of whole grain supplements, (ii) type of supplementary grain fed, and (iii) level of feeding of supplementary grain. Unsupplemented goats grew 95 g cashmere with mean fibre diameter 17.01 m and mean cashmere fibre length 52 mm. During the period of pen feeding unsupplemented goats lost 95 g liveweight/day. Provision of whole grain supplements significantly increased total yearly cashmere growth to 179 g (+88%) which was 26 mm longer (50%) and 2.12 m coarser (26%) than cashmere grown by unsupplemented goats. Increasing the level of supplementary grain resulted in linear increases in feed intake, cashmere growth, fibre diameter and length. For each 100 g/day of lupin or barley grain fed during the pen-feeding period the regression coefficients indicated an extra 33 g of cashmere was grown, which was 0.6 m coarser and for barley 10 mm longer and for lupins 17 mm longer. Cashmere (fibre length/fibre diameter2) ratio was increased by supplementary feeding, increased feed level and liveweight gain during the experimental period. Relatively longer cashmere was produced as the level of nutrition increased. It is clear that a base diet of senescent temperate pasture that is low in digestible nutrients and low in nitrogen results in suppressed cashmere growth. Strategic grain supplementation for at least 9 weeks during late summer and autumn has the potential to significantly increase cashmere production and cashmere fibre length when adult cashmere goats are grazing pastures deficient in digestible energy and nitrogen. However feeding high levels of lupin and barley grain to adult goats is contra indicated as cashmere mean fibre diameter may exceed market limits. The practical application of the results is discussed in light of previous research.

The effects of intradermal injections of spermidine on the growth rate of fibres and mitosis of wool follicles in Merino lambs

2002 ◽  
Vol 75 (1) ◽  
pp. 33-40 ◽  
Author(s):  
S. M. Liu ◽  
A. Murray ◽  
A. C. Schlink ◽  
G. Mata ◽  
D. G. Masters
Keyword(s):  
Growth Rate ◽  
Cell Proliferation ◽  
Cell Division ◽  
Fibre Diameter ◽  
Fibre Length ◽  
Optimal Growth ◽  
Contralateral Side ◽  
Length Growth ◽  
Local Supply ◽  
High Doses

AbstractPolyamines (putrescine, spermidine and spermine) are required for optimal growth in all cells, and are essential for cell proliferation and growth of cultured wool follicles, with an optimal concentration of spermidine required for the fibre elongation. The effects of a local supply of exogenous spermidine on the rate of cell division in the wool follicles, the length growth rate and diameter of fibres were therefore examined in Merino lambs. Three groups of eight lambs (40 kg) were given food at 1·2 ✕ maintenance. Spermidine was injected intradermally into a small patch (3 ✕ 3 cm) on the left flank three times per day for 7 days at one of three concentrations: 1·38, 2·75 or 4·58 џmol in 0·8 ml volume. The same volume of saline was injected into the contralateral side as a control. The concentration of spermidine in the skin patch 3 h after injection on day 7 increased by proportionately 018, 0·33 or 0·41 (P < 0001) respectively. The rates of cell division in the follicle bulb 3 h after the spermidine injection were proportionately 0104, 0184 and 0·283 higher compared with the contralateral side (P = 0078 overall) for the low, medium and high doses of spermidine respectively and differed between the three doses (P < 005). The fibre length growth rate, as measured using autoradiography, was proportionately 0099, 0117 and 0156 higher than that of the contralateral side (P < 0001 overall) for the low, medium and high doses of spermidine respectively, but differences between doses were not significant (P > 005). Spermidine injection did not result in a significant change in fibre diameter during the treatment period. The ratio of fibre length growth rate to fibre diameter was increased by the injection of spermidine (P < 0001). The results suggest that injecting extra spermidine into the skin altered spermidine homeostasis in the skin, stimulated cell proliferation and resulted in increased fibre growth.

Influence of liveweight, liveweight change, and diet on wool growth, staple strength, and fibre diameter in young sheep

1998 ◽  
Vol 49 (2) ◽  
pp. 269 ◽  
Author(s):  
D. G. Masters ◽  
A. D. Peterson ◽  
G. Mata ◽  
S. M. Liu
Keyword(s):  
Management Strategy ◽  
Fibre Diameter ◽  
Experimental Period ◽  
Canola Meal ◽  
Wool Growth ◽  
Lupin Seed ◽  
Staple Strength ◽  
Wool Yield ◽  
Fleece Weight

The effects of initial liveweight, liveweight change, and composition of the diet on wool growth and staple strength in weaner sheep were investigated. Weaner wethers (64) were allocated to treatments in a factorial design (23). The factors were initial liveweight (heavy, 33 kg; light, 25 kg), liveweight change (fed at maintenance for 56 days, or 28 days at 0 ·6×maintenance then 28 days at 1·6×maintenance), and diet (lupin seed based diet or canola meal based diet). The heavier weaners grew approximately 1·9 g/day more wool than the light sheep during the experimental period and this resulted in a higher clean fleece weight (1·8 v. 1·4 kg), staple strength (37 v. 27·4 N/ktex), and fibre diameter (18·0 v. 17·4 µm). Substituting canola meal for lupin seed increased wool growth during the experiment and clean wool yield, but did not affect clean fleece weight or staple strength. The weaners fed to lose and then gain weight grew wool with a lower staple strength than the weaners fed to maintain weight through the experiment (28·6 v. 35·8 N/ktex), but there were no differences in any of the other fleece characteristics. The ratio of wool growth to dry matter intake (DMI) was higher in the sheep fed canola meal than those fed lupins (by approximately 1·5 g/kg DMI) and higher in weaners losing weight than those fed to maintain weight (by approximately 4·5 g/kg DMI). From a practical perspective, these results indicate that initial liveweight and liveweight change both influence staple strength and wool growth and need to be included in any management strategy to improve wool quality of young sheep.

A multi element supplement for grazing sheep. I. Intake, mineral status and production responses

1992 ◽  
Vol 43 (4) ◽  
pp. 795 ◽  
Author(s):  
CL White ◽  
DG Masters ◽  
DW Peter ◽  
DB Purser ◽  
SP Roe ◽  
...  
Keyword(s):  
Effective Means ◽  
Subterranean Clover ◽  
Experimental Period ◽  
Essential Elements ◽  
Blood Concentrations ◽  
Safety Margins ◽  
Grazing Sheep ◽  
Staple Strength ◽  
Fleece Weight ◽  
Mineral Lick

The safety and effectiveness of a loose mineral lick containing all known essential elements was investigated in an experiment in which 96 Merino weaner wethers grazed subterranean clover/grass pastures during summer and autumn. The treatments were no supplement or mineral mix ad libitum; there were four plots of 12 sheep per treatment. The mean intake was 29 � 1 g/head per day of the mix and those offered the minerals had blood concentrations of P, S, Se and vitamin BIZ in the normal range. Unsupplemented Control sheep had blood concentrations of P, S and Se in the deficient range for all or part of the experimental period. There was an estimated 1.6-fold range in mineral intake between sheep, and none refused the mix. Concentrations of Cu, Cd and F in tissues and bone of sheep offered the mineral mix were within accepted safety margins. The mineral lick increased live weights by 4.5 kg during summer (P < 0 - 05), increased clean fleece weight by 240 g (9%), (P < 0.01), and increased wool staple strength by 15 N/kt (40%), (P < 0.01). The pasture concentrations of most macro elements decreased between November and March, respective concentrations being (g/kg DM): K, 17- 7 and 1.9; Na, 4-0 and 0.31; S, 1.6 and 0.9; N, 12.9 and 10; P, 1-95 and 1-08; Ca, 7-86 and 9-75; Mg, 2.29 and 1-38. Changes in trace element concentrations were small, the respective values being (mg/kg): Cu, 9.7 and 10-3; Mn, 47 and 67; Fe, 56 and 323; Zn, 20 and 20; Mo, 0-2 and 0.35; and Se, 0.015 and 0.032. The loose mineral lick was a safe and effective means of supplying macro and trace elements to grazing sheep during summer.

The effect of nutrition on fibre growth in the alpaca

1997 ◽  
Vol 64 (3) ◽  
pp. 509-512 ◽  
Author(s):  
A. J. F. Russel ◽  
H. L. Redden
Keyword(s):  
Growth Rate ◽  
Adult Male ◽  
Fibre Diameter ◽  
Fibre Length ◽  
Weight Yield ◽  
Fibre Growth ◽  
Maintenance Requirements

AbstractTwelve adult male alpacas were given either 0·67 (low) or 2·0 (high) × assumed maintenance requirements for a period of 6 weeks after which time each was transferred to the alternative level of nutrition for a further 6 weeks. Fibre samples were taken from two 10-cm2 areas on the mid-side position of each animal at 2, 6, 8 and 12 weeks, and measurements of fibre weight, yield (clean fibre weight/raw fibre weight), fibre diameter and fibre length made on the samples collected at weeks 6 and 12. The higher level of feeding resulted in higher clean fibre weight (low = 0·42 (s.e. 0·03); high = 0·53 (s.e. 0·04)mg/cm2 per day, P < 0·001) and fibre growth rate (low = 186 (s.e. 10); high = 223 (s.e. 14) yon/day, P < 0·05). Changes in yield (low = 0·917 (s.e. 0·006); high = 0·929 (s.e. 0·009)) and mean fibre diameter (low = 31·4 (s.e. 1·9); high = 32·1 (s.e. 1.6) \xm) were not statistically significant. Calculations showed that the increased weight of fibre attributed to the higher level of nutrition could be explained in terms of the observed increases in fibre-length and diameter but that, unlike the sheep in which the ratio fibre length: diameter remains relatively constant under varying nutritional regimes, the effect of nutrition in the alpaca has a proportionally larger effect on fibre length than on fibre diameter.

Lamb mortality and growth to weaning in commercial Merino flocks in Western Australia

1992 ◽  
Vol 43 (6) ◽  
pp. 1399 ◽  
Author(s):  
RW Kelly
Keyword(s):  
Western Australia ◽  
Fibre Diameter ◽  
Mortality Rates ◽  
Unit Change ◽  
Condition Score ◽  
Average Condition ◽  
The Mean ◽  
Staple Strength ◽  
Fleece Weight ◽  
Highly Correlated

Eighteen farm flocks of four-tooth Merino ewes (average of 371 ewes at lamb marking, range 278 to 511) were studied in 1987/88 ( n =8 ) and 1988/89 (n=10) over the period from 2 to 4 weeks pre-joining until 12 weeks post-lambing. All farms were located in the south-west of Western Australia, and the flocks started lambing between mid-April and mid-July. The average liveweights of ewes pre-joining ranged over 40.2 to 61.8 kg, and average condition scores ranged from 2.2 to 4.2. Mean liveweight changes of the ewes ranged over losses of up to 8.5 kg to gains of up to 10.4 kg between consecutive recordings at 2 to 3 month intervals up to 12 weeks post lambing, and condition score changes ranged over minus 1.2 to plus 1.2. The greatest losses in liveweight and condition score in many flocks corresponded with the period from mid-pregnancy to marking, the time of greatest nutrient demand of the ewe. There was considerable variation between flocks in the percentage of dry ewes (2.9 to 17.7%), lambs born per ewe present at marking (83.0 to 147.3%), lambs alive per ewe present at marking (66.3 to 123.2%), and lamb deaths as a percentage of total lambs born (10.9 to 29.8%). For single and twin-born lambs, the percentage of lamb deaths between flocks ranged from 6.0 to 19.9% (mean = 11.0%) and 19.1 to 63.2% (mean = 33.1%) respectively. Of the ewes giving birth to twins, an average of 9.6% lost both lambs. The mean birthweights were 4.4 kg (range 3.6 to 5.1 kg) for singles and 4.0 kg (range 3.3 to 4.5 kg) for twins, and were highly correlated (r = 0 - 74, n = 13 flocks, P<0.01). Lamb growth to marking averaged 232 g head-1 day-1 and 205 g head-1 day-1, and from marking to weaning 198 g head-1 day-1 and 193 g head-1 day-1 for single and twin-born lambs respectively. The mortality rates of both single and twin-born lambs were highly correlated with mean liveweight of the ewes at mid-pregnancy (r = -0.64, P<0.01; r = -0.75, P<0.001; respectively). A kilogram increase in mean liveweight at mid-pregnancy was associated with declines in the mortality rates of single-born lambs of 0.7% units (s.e. = 0.23), and of twin-born lambs of 2.2% units (s.e. = 0.57). Mortality rates of the singles were highly correlated with that of twins (r = 0.86, P<0.001), with a 1% unit change in death rate of singles being associated with a 2.5% (s.e. = 0.41) unit change for twins. Mortality rates of twins were associated with mean cotyledon diameter measured in mid-pregnancy (r = -0.48, n = 13, P<0. l0), and mean umbilical resistance to blood flow (r = 0.78, n = 9, P<0.02). Growth from birth to weaning of single-born lambs was associated with the mean liveweight of the flock in mid-pregnancy (r = 0.72, P<0 .001). Clean fleece weight and mean fibre diameter of the fleeces from single.bearing and rearing ewes were correlated with mean ewe liveweight in mid-pregnancy (r = 0.56, P<0.05; r = 0.70, P<0.01; respectively). Staple strength was correlated with mean ewe liveweight at marking for both single and twin producing ewes (r = 0.72, n = 18, P<0.01; r = 0.74, n = 9, P<0.05; respectively). It was concluded that liveweight of the ewe in mid-pregnancy, which represents the sum of starting liveweight and liveweight change, is the most important single and practical criterion that can be used by a farmer to set the goals for nutritional management of the flock over pregnancy to improve lamb survival.

Maternal and genetic influences on follicle and fleece development in Lincoln and Welsh Mountain sheep—a study involving egg transfer

1965 ◽  
Vol 7 (3) ◽  
pp. 333-345 ◽  
Author(s):  
G. Wiener ◽  
J. Slee
Keyword(s):  
Post Partum ◽  
Fibre Diameter ◽  
Fibre Length ◽  
Maternal Environment ◽  
Maternal Influences ◽  
Wool Production ◽  
Secondary Follicle ◽  
Specific Effects ◽  
Fibre Growth ◽  
General Average

SUMMARYBy mean of egg transfer, lambs of a large breed of sheep (Lincoln) were born out of dams of a small breed (Welsh Mountain) and vice versa. One breed was approximately twice the weight of the other. The effects of this contrast in maternal environment upon the development of the wool follicles and upon subsequent wool production are described in this paper. These effects are compared with differences between singles and twins.Data were obtained from skin and wool samples taken at birth and at 84 days post-partum.Genetic differences were the largest single source of variation for most of the component characters of the skin and fleece.Strong maternal influences were in evidence. These were shown to have affected both Lincoln and Welsh lambs in a general (average) way and also to have had different, specific effects on each genotype as shown by genotype-environment interactions. Differences in maternal environment following egg transfer, clearly affected follicle density, primary/secondary follicle ratio, fibre medullation, fibre diameter and fibre length. Wool production was not affected, apparently because reduced follicle density was associated with increased fibre length.In the comparison between singles and twins the latter appeared to suffer a post-natal rather than a pre-natal restriction of secondary follicle development, and in the absence of extra fibre growth there was reduced wool production at 84 days.

The effect of birth status on the level and efficiency of wool production by new zealand corriedale two-tooth rams and ewes

1982 ◽  
Vol 35 (3) ◽  
pp. 309-312 ◽  
Author(s):  
L. G. Butler
Keyword(s):  
New Zealand ◽  
Fibre Diameter ◽  
Fibre Length ◽  
Experimental Period ◽  
Individual Values ◽  
Wool Production ◽  
Wool Growth ◽  
Diameter Fibre ◽  
Valid Comparison ◽  
Maintain Body Weight

ABSTRACTForty-four single- and twin-born New Zealand Corriedale two-tooth ewes and rams aged 14 months were fed individually, in pens, a pelleted ration adjusted to maintain body weight after allowing for wool growth. The sheep were fed for a 3-month settling period, followed by a 3-month experimental period, during which wool growth, fibre diameter, fibre length and net efficiency of wool growth were measured.Since the wool-growth cycles of the two sexes were found to be out of phase, a valid comparison of the sex data was not possible. Such phase differences may be important in some experimental designs. Significant sex by birth status interactions were identified for all wool production parameters except fibre length, confirming that care must be taken in assigning correction factors during selection of rams and ewes. The general trend was for single-born ewes to produce more and coarser wool more efficiently than twin-born ewes, while the differences between single- and twin-born rams were much smaller. Single-born animals were heavier than twin-born (P<0·01).Individual values for wool growth and net efficiency varied by a factor of three within sex groups, indicating a considerable scope for selection

scholarly journals Genetic parameters for yearling wool production, wool quality and bodyweight traits in fine wool Merino sheep

2008 ◽  
Vol 48 (9) ◽  
pp. 1168 ◽  
Author(s):  
A. A. Swan ◽  
I. W. Purvis ◽  
L. R. Piper
Keyword(s):  
Genetic Parameters ◽  
Genetic Correlations ◽  
Fibre Diameter ◽  
Merino Sheep ◽  
Wool Quality ◽  
Staple Strength ◽  
Fleece Weight ◽  
Highly Correlated ◽  
Genetic Evaluations ◽  
Trait Groups

Genetic parameters were estimated for traits measured in the first year of production in a multi-bloodline flock of fine wool Merino sheep. Between 5025 and 9271 animals were measured, depending on the trait, and these animals were the progeny of up to 430 sires. Heritability estimates for fleece weight traits ranged from 0.37 to 0.49, while estimates for five wool quality traits ranged from 0.34 for staple strength to 0.66 for mean fibre diameter. For bodyweight, the heritability estimated at weaning was 0.20, and at the yearling age was 0.51. Maternal genetic effects were significant for fleece weight and bodyweight traits and were highly correlated between these trait groups, indicating that these effects are determined by similar groups of genes in both trait groups. While most genetic correlation estimates were either favourable or neutral, there were economically antagonistic correlations between fleece weight and mean fibre diameter, ranging from 0.15 to 0.30, and between mean fibre diameter and staple strength (0.26). Overall, the heritabilities and genetic correlations estimated in this fine wool population were similar to estimates from other strains, indicating that outcomes from selection programs will be similar across strains and that fine wool sheep can be included in across flock genetic evaluations with other strains.

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