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Selection by Stud and Commercial Breeders

Dohne Workshop Australia July 2016 Cameron McMaster. Selection by Stud and Commercial Breeders. Breeders can influence the economic performance, the genetic merit and the rate of improvement of their flocks by: Selecting superior rams in terms of the objectives they have set

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Selection by Stud and Commercial Breeders

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  1. Dohne Workshop Australia July 2016 Cameron McMaster Selection by Stud and Commercial Breeders • Breeders can influence the economic performance, the genetic merit and the rate of improvement of their flocks by: • Selecting superior rams in terms of the objectives they have set • Selecting replacement ewes on the basis of their performance The greatest scope for additional financial and genetic improvement is by selecting superior rams because of their greater genetic influences

  2. Visual Classing • The visual appraisal of young animals and the culling of animals with faults is critical for selection • Animals should be judged on the following criteria: • Type (wrinkle development) • Conformation • Wool and skin characteristics to be selected:

  3. Visual Classing Type (wrinkle development) . NO YES X Wrinkles are negatively correlated to Reproduction, Growth rate and Easy Care features

  4. Visual Classing Conformation Select for the ideal conformation Cull all faulty sheep X X X X

  5. Visual Classing Wool and skin characteristics Cull sheep with faults:Select sheep with: Pigment, black and brown fibres Loose pliable skin Hair Free growing wool Harsh wool quality Good staple length Poor colour Soft, pearly white wool Dry tip anddust penetration Good crimp and definition Dense, short and yolky Fluid yoke, staple and tip . .

  6. Visual Classing - Pigmentation Pigmentation on the face and legs may indicate the presence of floating black fibres in the fleece

  7. Visual Classing - Pigmentation Black Spots in the fleece Black hooves

  8. Selection Ewe Power Females are the basic business of the Livestock Breeder (Lasater) A Ewe’s main purpose is to produce lambs – As many as possible This should be the main yardstick by which ewes should be evaluated

  9. Ewe Power . The early marketability of Dohne lambs is the key to increased turnovers and higher gross margins Early marketability of lambs means that more ewes can be kept to produce more lambs to be marketed More lambs mean increased turnovers and profits A snowball effect to higher profitability

  10. Selection for Production - EWES • A commercial breeder’s flock structure should be: • Ewes in full production comprise 60% to 70% of the total flock. • Ewes that do not lamb and have dead lambs, should be culled. • Ewe age groups should be limited to 4. Ewes should be disposed of after their 4th lambing

  11. Selection for Production - EWES Fast growing lambs (all wether lambs and draft ewe lambs) should be marketed as early as possible – ideally between 4 and 6 months of age, and not later than the commencement of the next breeding season.

  12. Selection for Production - EWES • The selection of young ewes is done in 3 stages: • At weaning and prior to mating (cull ewes with faults) • Prior to mating (select for production) • Bodyweight breeding value (EBV) • Fibre diameter breeding value (EBV) • Fleece weight breeding value (EBV) • During the life of the animal (select for reproduction).

  13. Consider only ewes that pass visual appraisal with desired characteristics, in order of importance: • Body weight – because of the strong correlation between mating weight and conception • Fibre diameter and wool quality – attention should be paid to wool with soft handle, quality and crimp definition. • Fleece weight - cull ewes with very little or excessive wool Selection for Production - EWES

  14. Selection for Reproduction – Ewes High reproduction is the basis for profitability and flock improvement and will increase the rate of progress of important breeding characteristics. The selection strategy for a ewe flock: Mate young (45kg BW) Cull ewes that do not conceive. Give preference to twins Select for body weight and against wrinkles and woolly faces Cull ewes - with stillborn lambs - which must be assisted at lambing - which do not bond with lambs

  15. Selection of Rams • For fitness and hardiness: • Select rams that are genetically superior, with superior type - long, deep bodies, high on the leg and without wrinkles. • Give preference to rams with good body weights and ensure that fleece weights are not too high in relation to body weights.

  16. Selection of Rams • For reproduction and growth rate: • Rams must be genitally sound with good testes size • A libido and mating dexterity test completes selection • Look for rams with above average weaning weights • Choose rams with the best dam records, including: • Conception at first mating • Regular conception after first mating • Fecundity • Lamb survival to weaning • 100-day lamb growth rates

  17. Selection of Rams • For Fibre diameter and wool quality • Visual wool quality – soft, white wool with well-defined crimp and totally free of hair. • Avoid rams that have substantially increased their fibre diameter between tests • Avoid rams with a wide variation • in fibre diameter - (CV% over 20%) • Avoid rams with more than 5% of • fibres over 30 microns • (Comfort Factor - CF)

  18. Selection of Rams For Fibre diameter and wool quality

  19. Selection of Flock Rams • Choice of supplier is important. Breeders should: • Breed within the same environment as you • Rear rams as naturally as possible • To ensure breeding records are accurate: • The ram breeding flock should be large enough • Rams should be reared and tested in homogenous groups • To enhance reproduction: • The breeder should supply comprehensive breeding records • of the dams of all rams on sale.

  20. Selection With the information at your disposal it is possible to select ewes and rams that will improve your flock Cameron McMaster

  21. Wait. Wait, Listen to me. We are not just sheep – we are DOHNE MERINOS!

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