March 22, 2009

Angora (Mohair) Goat Basics: Breeding objectives

Agriculture, farming, husbandry, goats, Angora, Mohair, breeding, objectives

By Dr Clive Dalton



Breeding objectives in Angora goats
Breeders agree that all of these traits listed below are important, but they may put them in different orders of priority.

For example if you are spending hours treating goats for footrot and dealing with dirty rear ends with worms, then getting rid of these two traits for an “easy-care” flock is of prime importance.

Many would add other traits to the list such as physical features such as foot shape and udder shape and teat size.

  • Increased fleece weight.
  • More kids/doe mated.
  • Finer fibre diameter.
  • Free from hair and kemp.
  • Faster growing young stock.
  • Resistance to worms and footrot.
  • White fibre free from pigment.
  • Satisfactory lustre.

Selecting physical features
The Mohair Producers’ Association set out some standards for Angora goats in the 1980s as follows:

Head: Neatly formed with jaws fitting well. Covered in good quality mohair, the face with short fine hair. Ears should be long and pendant covered with short fine hair. Horns on bucks must be a minimum of 25 mm apart bending backwards, not too near the neck and spreading.

The horns of does should bend backwards and preferably outwards but in every case, in such a manner that they do not interfere with the head or neck. Naturally polled Angoras are accepted. Pigmentation of the skin on the face and ears should not be discriminated against.

Faults include a sparse kempy face and no mohair covering the head, although these are not great cause for concern if the Angora has a heavy, high quality fleece. Other faults of the head are:
  • Badly overshot or undershot jaws
  • Folded ears
  • Black hairs
Forequarters and legs: Neck of medium length fitting smoothly into the shoulder. Forelegs strong and straight, pasterns firm and hooves correctly formed. Faults are:

  • Hollow behind the knees
  • Bandy legs
  • Weak pasterns and splayed hooves

Barrel: Back strong and reasonably straight. A good balance between the parts forming the barrel will add symmetry and general appearance of the animal.
Hindquarters & legs: Rump reasonably broad, forming more or less a straight line with the back and withers. Good space between pin bones. Thighs well fleshed. Hind legs strong and square standing, pasterns firm, hooves well formed. Faults are:
  • Narrow hindquarters.
  • Weak pasterns and splayed hooves.
  • A crooked tail and tail covered with coarse hair.
Male organs: Must be well developed. Disqualification for any abnormality such as split purses, and small or missing testicles. Clinical abnormalities may affect fertility.

Female teats: Females should have two well-formed teats.

Fleece: A good quality mohair fleece should be fine in mean fibre diameter, soft and silky to touch, lustrous and white, forming stylish wavy blunt staples or ringlets of even length. It should not contain medullated or pigmented (coloured) fibres.

Kemp: Should be at a minimum level.

Medullated fibres: These are hollow and tend to be coarse which results in them being stiff, harsh handling, brittle, chalky in appearance and lacklustre. They dye paler shades than other fibres. Short kemps tend to comb out easier than long kemps. Straight hair on the tail or forelock often points to medullation in the fleece

Fineness & evenness of mean fibre diameter: Important for production of high quality yarns. Soft handling mohair generally indicates fineness. Mohair tends to become coarser with age of animal.

Lustre: Tends to be associated with soft handling for a given diameter and also with ability to be dyed to bright colours.

Length: Evenness of length and good growth are necessary for processing. Fibres should grow at a rate of 20-25mm or more per month. Blunt tips to the staples indicate evenness of length of fibre within the staples.

Density: The percentage of skin area covered by fibres. When the fleece is parted, the skin should e well covered with mohair fibres and only very minimal areas of skin showing between the staples.

Character & style: Mohair should display good character, i.e. even waviness throughout the staple length.

Genetic principles: Refer to Dalton, D.C (1980) in further reading.

Key principles to remember:
  • Traits can be measured either subjectively (e.g. In kg or mm) or objectively by eye (e.g. handle of fibre or shape of ears). It’s easy to let too many subjective traits swamp the importance of objective ones.
  • The more traits you select for, the slower is the progress in any individual trait. So if you want to see real progress in your lifetime, select for only a few important traits, e.g. fleece weight, fibre diameter and feet.
  • Genetic gain is determined by this formula:
Genetic gain/year = (Heritability x Selection Differential)/Generation Interval.


Making rapid gains
If you want to make rapid gain:
  • Heritability should be high
  • Selection Differential (SD) should be large and
  • Generation Interval (GI) needs to be small.
The SD is the powerhouse of the formula where you can apply maximum selection pressure when deciding which animals to be parents for the next generation.

Heritability is the strength of inheritance of a trait, i.e. how much is passed on to the next generation. See table below. Where heritability is low, the environment has a much greater effect than genetics.


Selection Differential.
This is how much better the selected parents (males+females averaged) are than the average of the population they came from. You can have a much higher SD for males than for females.

Generation Interval.
This is the average age of parents when offspring are born. The fastest you can go is to mate buck kids to doe kids, which may not be what you want to do for husbandry reasons.

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