convegno internazionale le vie della lana new perspectives on fine fibre animals research hugh...
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Convegno InternazionaleLe Vie Della Lana
New perspectives on fine fibre animals
research
Hugh Galbraith
Email: [email protected]
UNICAM, Ottobre 2007
New perspectives…..
Following recent review in….
Presentation on conclusions of research on:
• Wool producing animals• Basic structures in skin for fibre production• Fibre growth patterns• Nutrition
Ecological production: fibre from animals: new thinking
• Product from environments which need not compete with intensive plant production (food, biofuels)
• Renewable sustainable product… compared with oil-based products and
• Is getting expensive
• Maintain human habitation on land…
• Hair produced in 1o and associated 2o follicles in the skin.
2o follicle products (eg cashmere, mohair, alpaca) most valuable.
1o follicle products coarser, limited commercial value
- contaminant of 2o follicle products– may compete for nutrients
– Vary among animal BREEDS
Hair fibre biology: background
primary
secondary
Scottish Breeds
Course wool
• Blackface/Cheviot up to 5kg) etc: coarse wool ( < 30 µm);
• Hardwearing, carpets ( clothing- Harris TweedTM )
• – West Coast of Scotland – Nike trainers))
Such UK sheep breeds: conclusion
• Quality of fleece generally of limited economic value
• Costs of shearing sometimes hardly covered
• One solution???
• Source animals with finer, more valuable fibre
Merino type
Fine wool
• Merino… genotypes > 16µm
• Yields: 5 kg+ (!!!!)
• Use: fine quality garments and textiles
Goat “wool”Angora: mohair
• Predominantly single “coat”, high yield (10 lose activity by 3 months postnatal)
Goat “wool” Cashmere-bearing goat
• “Double-coated” animal (20 cashmere lower yield: 10 remains active), depending on genotype
Goats(20 follicle products)
• Cashmere-”bearing” ( 11-18+µm); 0.05 -1.0kg (Chinese): (Daylength-sensitive)
• Angora goats (mohair) ( 22 - 35µm): 2.0 - 5.0kg (limited effect of daylength).
• Smooth cuticular surface, strong uptake of dyes )
• Cashgora (intermediate)
• NB Contamination with 10 follicle products including medullated coarse fibres
South American Camelids( 20 follicle products)
• Vicuna: double coated (< 15 μm)• Guanaco: double coated (15-18μm)(0.5-1.5kg,UK)
(medullated)• Alpaca: single coated (18-30 μm)(1.5-5.5kg) • (Domesticated) ( Suri vs Huacaya genotypes)• Llama: double coated (>20 μm)(1.5-2.0kg)• (Domesticated)
• NB: Yield greatest in males + increasing age but
• reduced fineness: typical general response in animals
Angora rabbits
• Production: 1.1-1.5 kg/year ( 30% of body weight)
• Diameter (10-13µm: medullated)
• NB Husbandry ( avoid staining, contamination of fibre (cages – animal welfare in UK)
Hair follicle biology: where wool comes from
• Hair follicles are complex structures
• Vary in size and accessory structures • (sudoriferous gland; arrector pili muscle only in 10 fibres)
• Shape and lustre of hair fibre product is important• PIGMENTATION/COLOUR
• Patterns of activity varies
Season effects: Follicle cycle Anagen Growing
Catagen Stops growingTelogen Follicle rests
Anagen Hair sheds Follicle reforms and fibre grows again
SKIN dimensions 2.5 mm (length)
0.1 mm (width)
Fibre
Sebaceous gland
Fibre cuticle
Cortex (new fibre)
SKIN SURFACE
HAIR FOLLICLE IN SKIN
New cells
New fibre
Fast cell division
Long anagen phase
Small diameter
- depends on:
1.Number of cortical cells
2.Size of cortical cells
3.Rates of proliferation
4.Dimensions of dermal papilla
Rate of growth
d.p. diameter
Optimal fibre growth
• Hair follicles affected by– competition for nutrients with other tissues (protein, energy,
vitamins, minerals etc.)
– Fibre production usually has high priority
Importance of whole animal - fibre only one component…
maintenance + production• Nutrients used for– Affected by growth, lactation, pregnancy
Sheep Wool: Increased protein in diet
Give more fibre on high protein diet (one study). Rate of fleece production, + 33%
Fibre diameter, + 8% Rate of length growth, + 26%
Sheep Wool: Increased protein in diet
• N.B. Sheep wool response to dietary protein supply is usually greater than in cashmere (Yield (weight ) and diameter).
• Don`t forget :
• ALSO OTHER NUTRIENTS, such as ENERGY, minerals and vitamins…
Grazie per la vostra attenzione
Caledonian Pine-Glen Affric Eilean Donan castle by night
Strathisla Distillery Standing stones in Calanais, Lewis Highland cow
Departmental website: www.abdn.ac.uk/agfor
Hair Fibre Function: Evolutionary Advantage
• Environmental protection
• Response to environmental change
• Thermal insulation
• Dispersal of scents, pheromones
• Inter-animal/ recognition, display
• What happens in cells of the follicle?
Season effects:Anagen Matrix cell division Protein Deposition Hair growth
Catagen Apoptosis of matrix Club hair forms
Telogen Follicle shortens,
resting
Anagen Hair sheds Follicle reforms
SKIN dimensions 2.5 mm (length)
0.1 mm (width)
Pilary canal
Sebaceous gland
Fibre cuticle
Cortex
GFollicle neck
Glands!
FSloughing Zone
EConsolidation Zone
DKeratogenous Zone
C
BElongation ZonePre-elongation Zone
AMitotic zone of bulb(Proto-oncogenes)
Fibre cuticleCortex
Blood Vessels
Hair follicle gene Expression
Dermal papilla
Basement membrane
Dermis
Epidermis
Outer root sheath
Inner root sheath
Vascular
Embryo/Fetus Development
Epidermis dermis
ChemicalSignals
- developing follicle