Studies on Western Australian Merino sheep. 1. Stud, strain and environmental effects on hogget performance

1992 ◽  
Vol 43 (6) ◽  
pp. 1381 ◽  
Author(s):  
RP Lewer ◽  
RR Woolaston ◽  
RR Howe
Keyword(s):  
Fibre Diameter ◽  
Strain Differences ◽  
Average Fibre Diameter ◽  
Weaning Age ◽  
Average Fibre ◽  
Males And Females ◽  
Wool Yield ◽  
Fleece Weight ◽  
Western Australian ◽  
Australian Merino

A 6 year study is reported of Merino studs and strains (Peppin, Collinsville and Bungaree) in Western Australia. Wool and body traits of males and females were measured, with additional subjective traits assessed on females. The effects of strain, stud (within strain), birth year, dam age, birth rearing rank, weaning age and their interactions were estimated using least squares procedures. When tested against studs, strain differences were significant for fibre diameter (both sexes), clean wool yield and about half of the subjective traits (females) but for none of the liveweights. Stud and year effects were significant for all traits, as was their interaction for most traits. Some studs were more stable between years than others in both clean fleece weight and average fibre diameter. Of the remaining effects, birth rearing rank influenced the greatest number of traits, while dam age only affected yield in ewes and some early liveweights. Peppins produced wool 2.0-2.3 microns finer than Bungarees, but not significantly different from Collinsvilles. Peppins also had the best subjective wool scores, but had the highest wrinkle scores and scored poorly on other subjective body traits. Twin-born hoggets produced 0.05-0.15 kg less clean wool than their single-born contemporaries, and their fleeces were about 0.4 microns coarser with poorer subjective qualities. Twins were also lighter from birth (by 23%) up to 17 months (by 5%) in females. Late-born lambs had higher birth weights, but lower subsequent weights, persisting until 12 months in females.

Wool yield and characteristics of Dorset, Leicester and Sunffolk breeds and their ‘DLS’ cross

1977 ◽  
Vol 88 (3) ◽  
pp. 651-653 ◽  
Author(s):  
M. H. Fahmy ◽  
J. A. Vasely
Keyword(s):  
First Generation ◽  
Fibre Diameter ◽  
Fibre Length ◽  
Wool Production ◽  
Average Fibre Diameter ◽  
Average Fibre ◽  
Wool Yield ◽  
Fleece Weight

SUMMARYGreasy fleece weight (12 months growth) and wool samples from hip and shoulder regions were taken on 15 Dorset, 20 Leicester, 20 Suffolk and 17 DLS ewes (a cross of ½ Dorset, ¼ Leicester, ¼ Suffolk obtained by mating DL rams to DS ewes and DS rams to DL ewes). The purpose of the study was to compare wool production and characteristics of the first generation of DLS with that of the three breeds of origin. Wool production of DLS was 3·58 kg, 8·8 and 14% higher than that of Suffolk and Dorset, but 11% lower than that of Leicester (P< 0·01). The percentage of clean wool was highest in Leicester (78·3%), followed by DLS, Dorset and Suffolk (76·1, 74·3 and 70·5%, respectively). The average fibre diameter of the DLS and Leicester was 38 /m, 4 /m thicker than that for Suffolk and Dorset (P < 0·01). Average fibre length was 15 cm in DLS and Dorset, 6 cm shorter than in Leicester, and 3 cm longer than in Suffolk (P < 0·01). The variability in fibre diameter and length was highest in Leicester, followed closely by DLS.

Studies on Western Australian Merino sheep. III. Genetic and phenotypic parameter estimates for subjectively assessed and objectively measured traits in ewe hoggets

1995 ◽  
Vol 46 (2) ◽  
pp. 379 ◽  
Author(s):  
RP Lewer ◽  
RR Woolaston ◽  
RR Howe
Keyword(s):  
Economic Value ◽  
Fibre Diameter ◽  
Selection Procedure ◽  
Parameter Estimates ◽  
Average Fibre Diameter ◽  
Genetic And Phenotypic Correlations ◽  
Average Fibre ◽  
Objectively Measured ◽  
Western Australian ◽  
Australian Merino

Between 1440 and 2084 Merino hoggets were scored for visual traits, with the number of records differing according to the traits. Eight wool traits and seven body traits were subjectively assessed, while four wool traits and five serial liveweights were measured. Heritabilities for all subjective traits were estimated, with sire models using restricted maximum likelihood, as were genetic and phenotypic correlations between subjective and objective traits. Heritability estimates for back wool, lock thickness, wool character, underline, condition, wool colour, hock shape, feet shape, face cover score, neck wrinkle, breech wrinkle and side wrinkle were moderate (0.1 to 0.3), while those for visual fineness and wool handle were high (0.34 and 0.41), and overall score, low (0.06). Correlations between these traits and objective traits having economic value (wool weight, average fibre diameter and liveweight) were low or negligible, indicating that it may be more efficient if classing traits are not used to the exclusion of objectively measured traits. However, under some circumstances, they may have potential for increasing selection efficiency or used as an inexpensive first step in a two-stage selection procedure.

The effects of breed, crossbreeding and other factors on variation in fleece and skin traits

1980 ◽  
Vol 30 (3) ◽  
pp. 417-429 ◽  
Author(s):  
J. A. Woolliams ◽  
G. Wiener
Keyword(s):  
Unit Area ◽  
Fibre Diameter ◽  
Fibre Length ◽  
Live Weight ◽  
Strong Relationship ◽  
Average Fibre Diameter ◽  
Wide Range ◽  
Average Fibre ◽  
Fleece Weight ◽  
The Relationship

ABSTRACTBreed and crossbreeding significantly affected variation in 10 fleece, follicle density and fibre diameter traits in 12-week-old lambs. The breeds involved were the Scottish Blackface, South Country Cheviot, Welsh Mountain, Lincoln Longwool, Southdown and Tasmanian Merino, but the last only by rams.The Southdown came closest to the Merino in affecting density and diameter traits although the Merino crosses remained clearly distinguishable by their high follicle density. The Lincoln and Blackface crosses were notable for their long fibres and the Blackface crosses also had the least dense follicle and coarsest primary fibres. The coarsest secondary fibres were from Lincoln and Cheviot crosses. Heterosis estimates were obtained for crosses involving the Blackface, Cheviot, Welsh and Lincoln breeds. Significant heterosis was present in a wide range of traits but was not apparent in all crosses. Maternal differences were evident for many of the traits but with density these differences were apparently related to maternal effects on live weight of the lamb. The sex of the lamb, its birth type and rearing and its 12-week live weight significantly affected many of the traits.Among breeds and crosses a strong relationship was found between fibre density and average fibre diameter. The relationship suggested that breed variation in total fibre area per unit area of skin was small compared with the breed variation in its components. Fleece weight per unit area was most closely related to mean fibre length.

Productivity of classers' grades and sire selection differentials for fleece weight in two Merino studs

1982 ◽  
Vol 22 (117) ◽  
pp. 274
Author(s):  
BJ McGuirk ◽  
M Rose ◽  
R Scott
Keyword(s):  
Fibre Diameter ◽  
Selection Procedure ◽  
The Other ◽  
Average Fibre Diameter ◽  
Average Coefficient ◽  
Average Fibre ◽  
Selection For ◽  
Fleece Weight ◽  
Selection Differentials ◽  
Sire Selection

The normal practice in Merino studs is to class the rams visually into three grades: reserve rams from which the stud sires will be chosen; flock rams for use in commercial flocks; and culls. This study examined the productivity of these grades in three drops of rams from each of two studs. In each drop there were differences between the grades in greasy and clean fleece weight. In stud 1 the relative clean and greasy wool percentages in the reserve, flock and cull grades were 11 6,98 and 86, and 11 6,98 and 87 (P < 0.05), respectively. Clean fleece weights were not available on the visual culls in stud 2. In that stud the relative greasy wool percentages of rams in three grades were 112, 98 and 90, and the reserve rams also cut 15% more clean wool than the flock rams (P< 0.05). The differences between the grades in yield and average fibre diameter were less than they were for fleece weight and generally not statistically significant. In stud 1 the reserve rams were 0.6% higher yielding and 0.2 pm stronger than the drop average. The reserve rams were less variable than the other grades in fleece weights, yield and diameter. The largest differences were for fleece weights, where the differences in variation between the grades were significant. The average coefficient of variation for greasy fleece weight among the reserve rams in the two studs was 10.0% compared with the estimate of 13.2% for the whole drop. Selection differentials for fleece weight were estimated for stud sires selected from these six drops of rams. The efficiency of sire selection for either greasy or clean fleece weight was in excess of 70% of the maximum possible. In the four drops in which all sire replacements were selected exclusively from the reserves, the two steps in the sire selection procedure contribution almost equally to the sire selection differentials achieved.

Studies on Western Australian Merino sheep. II. Genetic and phenotypic parameter estimates for objectively measured traits on ram and ewe hoggets using different model types

1994 ◽  
Vol 45 (4) ◽  
pp. 829 ◽  
Author(s):  
RP Lewer ◽  
RR Woolaston ◽  
RR Howe
Keyword(s):  
Environmental Effects ◽  
Genetic Correlations ◽  
Fibre Diameter ◽  
Parameter Estimates ◽  
Merino Sheep ◽  
Phenotypic Correlations ◽  
Average Fibre Diameter ◽  
Heritability Estimates ◽  
Fleece Weight ◽  
Western Australian

Data from a Western Australian experimental flock of Merino sheep were used to estimate genetic and phenotypic parameters for clean fleece weight (CFW), greasy fleece weight (GFW), average fibre diameter (FD), and clean yield (Y) from hogget fleeces as well as liveweights at birth (BWT), weaning (3WT), 8-9 months (8WT), 11-12 months (11WT) and 14-15 months (14WT) of age. The estimates were derived for male and female hoggets using restricted maximum likelihood REML. Simple models were fitted in which most environmental effects were omitted for comparison with results from models containing all recorded significant environmental effects. There were no significant differences amongst heritability estimates between models or sexes. Genetic correlations were calculated between sexes for each trait, with none being significantly different to unity. Ranges of heritability estimates across models and sexes were: GFW, 0.30-0-42; CFW, 0.26-0.44; Y, 0.46-0.59; FD, 0.47-0.59; BWT, 0.16-0.33; 3WT, 0.32-0.39; 8WT, 0.22-0.36; llWT, 0-27-0.44; 14WT, 0.27-0.50. Estimates of genetic and phenotypic correlations were in reasonable agreement with other literature values. As with the heritability estimates, the model fitted did not result in important differences in either genetic or phenotypic correlations.

Direct and maternal genetic (co)variances for hogget liveweight and fleece traits in Western Australian Merino sheep

2002 ◽  
Vol 53 (3) ◽  
pp. 271 ◽  
Author(s):  
S. W. P. Cloete ◽  
J. C. Greeff ◽  
R. P. Lewer
Keyword(s):  
Genetic Correlation ◽  
Coefficient Of Variation ◽  
Genetic Correlations ◽  
Fibre Diameter ◽  
Phenotypic Variance ◽  
Selection For ◽  
Fleece Weight ◽  
Variance Estimates ◽  
Western Australian ◽  
Australian Merino

(Co)variance estimates for hogget liveweight, greasy fleece weight, clean fleece weight, clean yield, fibre diameter, and the coefficient of variation of fibre diameter were obtained for a Western Australian Merino resource flock. The flock encompassed 16 medium wool bloodlines and data were available for the period 1982–93. Direct additive genetic variances (h2) — expressed as a ratio of the total phenotypic variance within bloodlines — were estimated at 0.52 for hogget liveweight, 0.44 for greasy fleece weight, 0.42 for clean fleece weight, 0.63 for clean yield, 0.71 for fibre diameter, and 0.62 for coefficient of variation of fibre diameter. Maternal genetic variance estimates were significant (P < 0.05) only in hogget liveweight and fibre diameter, but components within bloodlines were low (0.05 for liveweight and 0.02 for fibre diameter). Direct within-bloodline genetic correlations of hogget liveweight as well as greasy and clean fleece weight with fibre diameter were positive (0.17, 0.31, and 0.31, respectively), suggesting that selection for bigger and heavier cutting sheep would generally lead to a broader fibre diameter. Liveweight was unrelated to clean yield and negatively related to coefficient of variation of fibre diameter (–0.17). Greasy fleece weight was negatively related to clean yield (–0.20). The genetic correlation of clean fleece weight with clean yield was positive (0.37). Wool quantity was, in general, positively related to coefficient of variation of fibre diameter, although the estimated genetic correlations were low (0.12 for greasy fleece weight and 0.07 for clean fleece weight). The genetic correlation between fibre diameter and coefficient of variation of fibre diameter was negative, and fairly low (–0.10). These results are discussed with reference to sheep breeding.

scholarly journals Fibre quality of South American camelids in Argentina: a review

2015 ◽  
Vol 56 ◽  
pp. 97-109 ◽  
Author(s):  
J.P. Mueller ◽  
F. Rigalt ◽  
H. Lamas ◽  
D.M. Sacchero ◽  
A.K. Cancino ◽  
...  
Keyword(s):  
Fibre Diameter ◽  
Fibre Production ◽  
Fibre Quality ◽  
South American Camelids ◽  
Average Fibre Diameter ◽  
Breeding Programmes ◽  
Vicugna Vicugna ◽  
Average Fibre ◽  
Production Area ◽  
Fleece Weight

SummaryArgentina's annual camelid fibre production is estimated at 60 000 kg for llama (Lama glama), somewhat more than 2 000 kg for guanaco (Lama guanicoe) and about 845 kg for vicuña (Vicugna vicugna). The potential for increasing these amounts is huge considering that barely 30 percent of llamas are shorn and considering the size of the wild camelid population in the country. A compilation of published and unpublished work confirms that almost 50 percent of the llamas are single-coated, about 40 percent have white fleeces and that average fibre diameter is about 22 µm in the main llama production area. In general, there is a wide variation in fleece weights and fibre quality between and within herds. However, a llama fleece classing and pricing system is not yet in place to motivate implementation of breeding programmes. Guanaco and vicuña fleeces are double-coated but the fine undercoat represents more than 80 percent of the fleece weight. The proportion of down fibre remaining after mechanical dehairing is only 50 percent in guanacos and 70 percent in vicuñas. The guanaco undercoat fibre diameter is about 16 µm and vicuña fibre diameter is typically between 13 and 14 µm. Both fibres are relatively short. Research is needed to establish optimum shearing season and shearing frequency that results in fibre quality demanded for handcraft and industry in each of the three species.

Genetic parameters for Australian maternal and dual-purpose meatsheep breeds. II. Liveweight, wool and reproduction in Corriedale sheep

1994 ◽  
Vol 45 (2) ◽  
pp. 469 ◽  
Author(s):  
LD Brash ◽  
NM Fogarty ◽  
AR Gilmour
Keyword(s):  
Litter Size ◽  
Genetic Correlations ◽  
Fibre Diameter ◽  
Dual Purpose ◽  
Scrotal Circumference ◽  
Average Fibre Diameter ◽  
Reproduction Traits ◽  
Component Traits ◽  
Average Fibre ◽  
Fleece Weight

Performance of sheep from a large Corriedale stud flock was assessed. Weaning and yearling liveweights, greasy and clean fleece weights, clean fleece yield and average fibre diameter records on approximately 3000 animals representing 64 sires were analysed. Also scrotal circumference of 1009 rams representing 27 sires were analysed. Some 3740 reproduction records over 11 years, for 980 ewes representing 114 sires, were also analysed. Heritability estimates were 0 34 �0.07 for weaning liveweight, 0.132 � 0.04 for yearling liveweight, 0.32 � 0.07 for greasy and 0.29 � 0.07 for clean fleece weights, 0.534 � 0 10 for clean fleece yield, 0-56 � 0 10 for yearling and 0 62 � 0 - 14 for hogget fibre diameters and 0.l5 � 0.11 for scrotal circumference. The genetic correlations between liveweight and fleece weight ranged from 0.13 to 0.34, and those for liveweight and fibre diameter were close to zero. The genetic correlations of scrotal circumference with liveweight and wool traits were positive and moderate. Reproductive performance in the flock was high, with fertility 92% and litter size 1.62, resulting in 148% lambs born and 130% lambs tagged alive of ewes joined. Estimated heritabilities for reproduction traits were 0-03 � 0.02 for lambs born and for lambs tagged, and the component traits, fertility 0 01 � 0 -02, litter size 0.04 � 0.03 and neonatal lamb survival was zero. Lambing date had a heritability of 0.06 � 0.03. Estimates of repeatability ranged from 0-04 � 0-01 for fertility to 0.07% 0.02 for lambs tagged and lambing date. Predicted heritabilities for the average of 3.8 records per ewe generally agreed with those estimated for average ewe lifetime performance, which ranged from 0.02 � 0.08 for fertility to 0.12 � 0.09 for lambs tagged and 0.l3 � 0.09 for lambing date.

Genetic correlations between early growth and wool production of crossbred ewes and their subsequent reproduction

2009 ◽  
Vol 49 (1) ◽  
pp. 17 ◽  
Author(s):  
R. A. Afolayan ◽  
N. M. Fogarty ◽  
A. R. Gilmour ◽  
V. M. Ingham ◽  
G. M. Gaunt ◽  
...  
Keyword(s):  
Growth Traits ◽  
Genetic Correlations ◽  
Fibre Diameter ◽  
Reproductive Traits ◽  
Early Growth ◽  
Wool Production ◽  
Component Trait ◽  
Average Fibre Diameter ◽  
Average Fibre ◽  
Fleece Weight

Genetic correlations between reproductive and productivity traits of ewes and their early growth, wool production and worm resistance traits were estimated among 2460 crossbred ewes. The ewes were progeny of 74 maternal breed sires and mainly Merino dams. The ewes were born over 3 years and had three joinings with a total of 6824 ewe joining records. The reproductive and ewe productivity traits included: (i) fertility (ewes lambing per ewe joined); (ii) litter size (number of lambs born per ewe lambing); (iii) rearing ability or lamb survival (lambs weaned of lambs born for lambing ewes); (iv) number of lambs born (NLBj) per ewe joined; (v) number of lambs weaned (NLWj) per ewe joined; (vi) total litter weight weaned (TWWj) per ewe joined; and (vii) the component trait average lamb weaning weight in the litter (AWW). The growth traits included the weight of the ewe at birth (BWT), weaning (WWT) and postweaning (PWWT), as well as growth rate pre- and postweaning. The wool traits included greasy (GFW) and clean fleece weight (CFW), yield and average fibre diameter (FD) at their first adult shearing. Worm egg count (WEC) during their first year was also recorded. Bivariate mixed models analyses using ASReml procedures were used to estimate the genetic correlations. The genetic correlations between TWWj and growth traits were positive and moderate to high and ranged from 0.34 for BWT to 0.61 for PWWT. Those for the other composite reproductive traits were slightly lower and ranged from 0.27 to 0.54 for NLWj and from 0.07 to 0.46 for NLBj. The genetic correlations between the overall measures of reproduction (NLBj, NLWj and TWWj) and GFW, CFW and FD were negative and generally low to moderate (–0.21 to –0.52). The correlations were generally larger for NLBj than for NLWj and TWWj. The genetic correlations between the reproductive traits and WEC were close to zero, except between AWW and WEC (0.42). The phenotypic correlations between the reproductive traits and the growth, wool and WEC traits were all close to zero. The genetic correlations were generally favourable between ewe reproduction and growth, with early selection for traits such as WWT and PWWT likely to give some improvement in subsequent reproduction and ewe productivity. In contrast, there appears to be a slight antagonism between reproduction and wool production. This study provides estimates of genetic correlations from crossbred ewes that add to the limited knowledge of these parameters that will improve the accuracy of genetic evaluation and prediction of the outcomes from breeding programs for meat and wool objectives that include reproduction.

Some wool characteristics of Karadi sheep in northern Iraq

1974 ◽  
Vol 83 (1) ◽  
pp. 171-174 ◽  
Author(s):  
K. E. Ghoneim ◽  
N. T. Kazzal ◽  
R. Kh. Abdallah
Keyword(s):  
Fibre Diameter ◽  
Fibre Length ◽  
Fibre Strength ◽  
Northern Iraq ◽  
Phenotypic Correlations ◽  
Average Fibre Diameter ◽  
Average Fibre

SUMMARYOne hundred and sixty-eight wool samples were collected from commercial flocks of Karadi sheep raised in the five provinces of northern Iraq. The wool characteristics dealt with were staple and fibre length, crimps, fibre diameter, medullation, fibre strength and elongation.The results showed that the Karadi wool is a long type of carpet fleece with average staple and fibre lengths of 19·3 and 23·5 cm, respectively. It had an average fibre diameter of 48·1 μ and contained 19·45 % medullated fibres. The number of crimps per 2 cm was 2·4. Average fibre strength and elongation were 24·8 g/5 cm and 31·8 % respectively. Phenotypic correlations between wool traits were studied.

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