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The SRS® System

SRS® or Soft Rolling Skin is a breeding system identified and developed by Dr Jim Watts. It is administered by The SRS® Company of JE & SM Watts and its trademarks identify the unique products and services of the business.

Merino studs passing stringent criteria for quality and ethical standards can pay a license fee and be accredited at different levels of genetic development.

The system is founded on extensive research and observation in biology, genetics, breeding and processing performance - and incorporates fundamental major gene functions.

After graduating in Veterinary Science in Sydney in 1972, Jim worked for the CSIRO on the follicle and fibre characteristics associated with the resistance of sheep to fleece-rot and fly strike. He continued research on the follicle and fibre characteristics that enhance fleece quantity and quality, collaborating with CSIRO colleagues in this area. He discovered that the fibre bundle was the basic unit of fleece structure, and from this fundamental finding, developed a fleece marker and sheep breeding system that produces Merino sheep of unparalleled fleece weight, fibre fineness and secondary follicle development. Over the past 13 years, he has worked as a breeding consultant to 40 leading Merino studs throughout Australia. He is Managing Director of the SRS® Company Pty Ltd.

Jim Watts is the technical advisor/classer to Severn Park.

SRS® Merino Wools: Breeding Biology and Processing Performance

These are new wools - the product of breeding methods developed by Dr Jim Watts.
The sheep possess levels of fibre density, length and quality much higher than previously recorded. As a result, the extra fineness, uniformity, softness and elasticity of this fibre type presents new processing opportunities.
Key processors are realising this (see Itochu-SRS® alliance).
Importantly, these are genetically induced fibre improvements which can be transferred through to the fabric. Supply of SRS® wools throughout Australia is growing steadily and consistently achieving premium prices at auction.
The two key differences between these wools and conventionally bred wools is that SRS® wools are comprised of fibre bundles (not staples or locks) that are bold and deep crimping (not 'true to type'). The fibre bundle is the basic unit of fleece structure and is seen clearly when fleeces are composed of a high density of highly aligned fibres. Staples, particularly thick locks, are entangled fibres of lower density animals that produce processing problems.
Bold and deep crimps in 'bundly' wool signifies that the fibres are simply growing faster under dense and therefore fine follicle arrangement and genetic control.
This ideal combination of true density and length ensures high fleece weights of fine microning wool of exceptional softness and quality.

Key Skin and Fibre Attributes Selected for at Severn Park under the SRS® System

Genetically fine primary and secondary follicles, with primary fibres finer than secondaries.
High number and density of secondary derived (compound) fibres.
High secondary follicle to primary follicle ratio.
High fibre alignment and high follicle density.
High expression of fibre bundles.
Bold, deep and highly uniform crimp. (Low fibre curvature; low SD of fibre curvature).
High lustre and a rich white nourishment. (Delivering high fleece-rot resistance).
Fast fleece growth: up to 0.5mm / day rams and 0.4mm / day in ewes on thin skins.
Extremely pliable thin skins: Desirable skin depth below 0.5mm
Extreme soft-silky handle (includes low Cv.u and low Sd.u) - derived from fine and uniform diameter, cylindrical fibre shape, deep & bold crimps but also smooth scales and different chemical structure of fibres.
High tensile strengths.

Schematic diagrams of the typical follicle and fibre configurations in SRS®, heavy tight skin and flat skin Merino sheep.
Fig (a) Horizontal skin sections show the structure of the follicle group.
Fig (b) Vertical skin sections illustrate alignment versus entanglement of follicles and fibres.

Where Severn Park Fits in the SRS® Breeding System

Dr Jim Watts, who has developed the SRS® breeding system, has 50 licensed studs nationally and hundreds of licensed commercial flocks working within this unique biological and genetic system. The top tier of the studs - those judged under clear and strict criteria by Dr Watts to meet certain criteria of advanced SRS® characteristics - are called Registered SRS® Studs. Severn Park is in this elite tier of only a few studs.

Implications of SRS® Major Gene Effects

Having animals of greater prepotency carrying major gene functions will have a revolutionary impact on the Australian Merino industry. The availability of advanced skin animals means there is scope to dramatically lift returns and profits in unprecedented fashion.
In building the new Meat Merino or Quad-purpose Merino, the SRS® major gene effect becomes the circuit-breaker, as it allows the components of an advanced skin and fibre to be maintained and developed whilst inputting the other components (meat, fertility & constitution) without compromise. As other major gene effects and superior traits are now identified in these other areas, we now know the task is achievable and is well under way.
In constructing the Quad-purpose Merino for the future, an added advantage is the linkage in the SRS® major gene effect between the SRS® skin and fibre component, and the fertility and milking component of the 4-teated Australian Milking Merino®.
(See section: The Quad Purpose Merino of the future: High quality wool, meat, fertility & constitution)
As a Registered SRS® Stud Severn Park is becoming more of a seedstock supplier - similar to certain dairy genetic deliverers.
Severn Park is responding with heavy re-investment in artificial insemination (AI) and embryo transfer (ET) work so as to extrapolate the advanced genetics and make these more available to clients (see Breeding Approach, Ram Sales and Client Servicing).

The Itochu-SRS® Company Alliance: A Customer-supplier Alliance for Superior Products

The recent alliance formed between the world's biggest buyer of Australian wools, Itochu (Aust.) and The SRS® Company to market SRS® wools is proof of the superior performance attributes of SRS® wools.
The alliance follows outstanding results with SRS® wools in Australian, Japanese and European mills, and their subsequent linkage to the retail sector.

See Fibre Marketing for full explanation.