Fleece rot and body strike in Merino sheep. IV. Experimental evaluation of traits related to greasy wool colour for indirect selection against fleece rot

1990 ◽  
Vol 41 (1) ◽  
pp. 139 ◽  
Author(s):  
HW Raadsma ◽  
BR Wilkinson
Keyword(s):  
Fibre Diameter ◽  
Selection Criterion ◽  
Indirect Selection ◽  
Objective Measurement ◽  
Genetic Potential ◽  
Wool Yield ◽  
Fleece Weight ◽  
Colour Development ◽  
The Cost

The potential for using indicators of greasy wool colour as indirect criteria for selection of sheep genetically resistant to fleece rot and body strike was examined. Nine traits based on the subjective grading of wool samples (1 trait), objective reflectance (6 traits) and colour development during incubation (2 traits) were evaluated for their genetic potential, ease and reliability of measurement, and relationship with other major production characteristics. The colour of wool was assessed in 949 Merino ewe hoggets representing the progeny of 134 sires before the induction of fleece rot. All colour traits were moderately heritable, ranging from 0.25 � 0.13 for subjective colour score to 0.40 � 0.14 (h2�.s.e.) for an objective reflectance index. Based on the combined estimate of the heritability of the indicator trait and its genetic correlation with fleece rot, indices based on the objective measurement of colour reflectance and colour development following incubation showed the highest genetic potential for indirect selection. Objective measurement of colour reflectance also showed a high genetic potential for indirect selection against body strike. Subjective colour assessment prior to the induction of fleece rot showed the lowest potential for indirect selection against both fleece rot and body strike. The cost of objective measurement of colour was less than that of colour development during incubation, and the former was found to be the most reliable indirect selection criterion in this experiment. A consequence of selecting solely for decreased greasy wool colour on other production characters is likely to result in decreased fibre diameter, increased wool yield, with a potentially small decrease in greasy fleece weight. Further evaluation of colour indicators as additional selection criteria should first focus on the likely role of fleece rot and body strike resistance as part of (national) breeding objectives. Only then can the full impact of using colour variables on the overall breeding aggregate be established.

Fleece rot and body strike in Merino sheep. VI. Experimental evaluation of some physical fleece and body characteristics as indirect selection criteria for fleece rot

1993 ◽  
Vol 44 (5) ◽  
pp. 915 ◽  
Author(s):  
HW Raadsma
Keyword(s):  
Genetic Correlation ◽  
Selection Criteria ◽  
Fibre Diameter ◽  
Selection Criterion ◽  
Indirect Selection ◽  
Merino Sheep ◽  
Breeding Programmes ◽  
Fleece Weight ◽  
Indicator Trait

Indicators of staple thickness, staple weight, staple density, wool weight cm -2, crimp frequency, dust penetration, fibre diameter (mean, variability), birthcoat score, and neck and body wrinkle were evaluated for their suitability as indirect selection criteria against fleece rot and body strike. The fleece traits were assessed in 949 Merino ewe hoggets representing the progeny from 134 sires in 15 contemporarily managed flocks. Fleece rot and body strike were assessed following experimental induction. In decreasing order of importance, variability (s.d.) in fibre diameter, average staple thickness, crimp frequency, variability (c.v.) in fibre diameter, mean fibre diameter, birthcoat score, staple density, variability in staple thickness, staple weight, and neck wrinkle score, accounted for a significant component of the variation in liability of sheep to fleece rot. Body wrinkle, variability (c.v.) in staple thickness, staple length, dust penetration, and wool weight cm-2 were not important. Based on combined estimates of the heritability of the indicator trait and its genetic correlation with fleece rot, variability in fibre diameter (s.d.) and birthcoat score showed the highest potential as indirect selection criteria. Variability in fibre diameter (s.d.) also showed a similar scope for selection against body strike. Indicators of mean staple thickness, crimp frequency, dust penetration and wrinkle score showed little or no scope for indirect selection against fleece rot or body strike. The role of variability in fibre diameter (s.d.) as an indirect selection criterion for fleece rot and body strike in designed breeding programmes which include other important objectives, will need to be further evaluated, given an undesirable genetic correlation with clean fleece weight. High between-flock correlations were observed for a number of fleece traits and susceptibility to fleece rot. Susceptible flocks were characterized by fleeces with longer, heavier, thicker staples with a lower crimp frequency, and higher fibre diameter with a higher variability. Predicting the susceptibility of flocks to fleece rot and body strike, through a between flock index based on the measurement of simple fleece traits, is suggested.

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.

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.

Inclusion of skin follicle traits in selection indices in breeding programs improves genetic gain in Australian fine-wool Merinos

2007 ◽  
Vol 58 (9) ◽  
pp. 921 ◽  
Author(s):  
M. Asadi Fozi ◽  
J. H. J. Van der Werf ◽  
A. A. Swan
Keyword(s):  
Body Weight ◽  
Coefficient Of Variation ◽  
Genetic Parameters ◽  
Genetic Correlations ◽  
Fibre Diameter ◽  
Selection Criterion ◽  
Breeding Programs ◽  
Breeding Objectives ◽  
Staple Strength ◽  
Fleece Weight

Genetic parameters for skin follicle traits, wool traits, body weight, and number of lambs weaned per ewe joined were estimated for 5108 10-month-old Australian fine-wool Merinos born between 1990 and 1996. These animals were descended from 261 sires and 2508 dams. The skin follicle number index that is based on skin surface area, and primary, secondary, or total follicle density were introduced as possible early-age selection criteria estimated at 6 months of age. Heritability estimates for total, secondary, and primary follicle number index were 0.45 ± 0.04, 0.46 ± 0.04, and 0.38 ± 0.04, respectively. The genetic correlations of total follicle number index with clean fleece weight, mean fibre diameter, staple strength, coefficient of variation of fibre diameter, body weight, and number of lambs weaned were 0.16, –0.67, 0.00, 0.03, 0.22, and 0.22, respectively. Responses to selection on indices including and excluding follicle traits were calculated based on the genetic parameters estimated, and with annual responses calculated using an optimised age structure. On average, 10% greater response was predicted when total follicle number index was used as an additional selection criterion in different micron premium scenarios. In comparison, skin follicle density had a smaller effect on genetic improvement. The extra response was ~1%. Similar index responses were obtained when total follicle number index was used as a replacement selection criterion for clean fleece weight, mean fibre diameter, and coefficient of variation of fibre diameter for breeding objectives with low emphasis on fibre diameter. In objectives with high emphasis on fibre diameter, unfavourable correlated responses in staple strength and CV of fibre diameter limited the effectiveness of using total follicle number index as a selection criterion. Although the use of total follicle number index as an additional selection criterion can be favourable for some breeding objectives, measuring this trait is currently cost prohibitive to inclusion in Merino breeding programs.

Medullated fibres and fleece characteristics in Corriedale hoggets from two flocks in Uruguay

2011 ◽  
Vol 51 (11) ◽  
pp. 1034 ◽  
Author(s):  
I. Sienra ◽  
K. Neimaur ◽  
R. Kremer ◽  
J. I. Urioste
Keyword(s):  
Genetic Variation ◽  
Fibre Diameter ◽  
High Variability ◽  
Fibre Content ◽  
Strongly Correlated ◽  
Veterinary Science ◽  
Wool Sample ◽  
Staple Strength ◽  
Wool Yield ◽  
Fleece Weight

The incidence of medullation in 549 Corriedale hoggets from two experimental flocks, its association with other characteristics of the fleece, and the sire effect were evaluated. The investigation was carried out during 2005–06 in hoggets from the Faculty of Agriculture and Faculty of Veterinary Science experimental flocks. Fleeces were weighed and samples were taken at shearing by picking 104 staples from fleeces to measure medullation. A mid-side wool sample was taken to determine wool characteristics (fleece weight, wool yield, mean fibre diameter, staple strength and length). A Dark Fibre Detector was used to identify total medullated fibres and fibre type: medullated fibres (med) and kemp, which were confirmed by light microscope. Mean total medullated fibres, med and kemp content per 10 g of clean wool were 4.2 ± 11.2; 2.0 ± 8.9 and 2.3 ± 4.9, and median values were 0.9, 0.0 and 0.7, respectively, in 549 fleeces. A high variability between samples and a higher proportion of hoggets with kemp fibres than those with med were observed. There were significant differences between sire families for total medullated fibre content/10 g, med fibre content/10 g and kemp fibre content/10 g, but there were no significant effects between flocks, years or interaction between them. Phenotypic correlations between medullated fibre content and wool characteristics were generally low (less than 0.19). In conclusion, medullated fibre content was highly variable between samples and was not strongly correlated with other fleece characteristics. Medullation varied between sire groups, suggesting genetic variation, which could be exploited to improve wool quality.

Hostile Takeovers and Anti-takeover Defenses in the Russian Corporate Market

2007 ◽  
pp. 70-84 ◽  
Author(s):  
E. Demidova
Keyword(s):  
Cost Benefit Analysis ◽  
Cost Benefit ◽  
Benefit Analysis ◽  
Costs And Benefits ◽  
Hostile Takeovers ◽  
Russian Market ◽  
Takeover Defenses ◽  
The Cost ◽  
European Markets

This article analyzes definitions and the role of hostile takeovers at the Russian and European markets for corporate control. It develops the methodology of assessing the efficiency of anti-takeover defenses adapted to the conditions of the Russian market. The paper uses the cost-benefit analysis, where the costs and benefits of the pre-bid and post-bid defenses are compared.

Changing Role of Agriculture in Income and Employment, and Trends of Agricultural Worker Productivity in Indian States

2020 ◽  
pp. 183-189
Keyword(s):  
Green Revolution ◽  
Positive Trend ◽  
Worker Productivity ◽  
Indian States ◽  
Agricultural Worker ◽  
The Sixties ◽  
High Level ◽  
The Cost ◽  
Changing Role

The productivity of land has been often discussed and deliberated by the academia and policymakers to understand agriculture, however, very few studies have focused on the agriculture worker productivity to analyze this sector. This study concentrates on the productivity of agricultural workers from across the states taking two-time points into consideration. The agriculture worker productivity needs to be dealt with seriously and on a time series basis so that the marginal productivity of worker can be ascertained but also the dependency of worker on agriculture gets revealed. There is still disguised unemployment in all the states and high level of labour migration, yet most of the states showed the dependency has gone down. Although a state like Madhya Pradesh is doing very well in terms of income earned but that is at the cost of increased worker power in agriculture as a result of which, the productivity of worker has gone down. States like Mizoram, Meghalaya, Nagaland and Tripura, though small in size showed remarkable growth in productivity and all these states showed a positive trend in terms of worker shifting away from agriculture. The traditional states which gained the most from Green Revolution of the sixties are performing decently well, but they need to have the next major policy push so that they move to the next orbit of growth.

Music publications in Galicia in the 19th — beginning of the 20th centuries: production, advertising, pricing

2019 ◽  
pp. 481-499
Author(s):  
Olga Osadtsia
Keyword(s):  
Book Publishing ◽  
Initial Form ◽  
Music Production ◽  
Bibliographic Information ◽  
Financial Factor ◽  
Determining Factors ◽  
Book Selling ◽  
The Cost ◽  
Import Trade

The main forms and methods of distribution of music publications in Galicia in the XIX — early XX centuries are scrutinized. The demand for the relevant music production is one of the determining factors in the formation of the musical publishing repertoire, its structure and special features in the process of the existence of music publications in society. It is noted that export-import trade in books has become especially widespread in Galicia; there are facts about the links between publishers and booksellers in Lviv and Warsaw. The basic types of presentation of book advertising of music products, its regional peculiarities, and ways of its placement are considered. Special emphasis is placed on the role of specialized press in the advertising of music products, typical examples of press advertising. The registration bibliographic information as the initial form of music bibliography and the forms of its compilation are distinguished. The emphasis is placed on the importance of thorough critical articles as a separate typological group of bibliographic publications under the conditions of formation of the Ukrainian bibliography, in which the main importance is given to the disclosure of the content and evaluation of the reviewed work. The combination of article genres and reviews on examples of separate publications by Stanislav Lyudkevych and Ivan Franko is traced. Special book-selling and book-publishing catalogs are characterized. While executing the marketing and advertising function, these directories were addressed primarily to foreign consumers and distributors (the so-called commissioners).One way to distribute music is to subscribe through libraries. A significant financial factor in the distribution of any printed matter was the price that depended primarily on the cost of each process associated with its publication. Keywords: music publications, bookstore, book-trading enterprise, advertising of publications, pricing.

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