Sheep - AgRIS

improvement of fine wool production. The committee suggested that level of exotic inheritance
should be maintained at W 50% except in the case of state sheep breeding farms and selected
areas.
6.2.2.2.1 Types of synthetic breeds evolved
A new superior carpet wool breed ‗‗Avikalin‘‘ has been evolved at the Central Sheep &
Wool Research Institute, Avikanagar through interbreeding and selection of Rambouillet x
Malpura halfbreds. The results of this crossbreeding experiment (Tables 6.3 to 6.5) revealed
that halfbreds are significantly superior for six monthly greasy fleece weight and fleece quality
in comparison to the first six monthly greasy fleece weight,staple length, average fibre diameter
and medullation percentage. The comparison of F2 with Fl however gave different results in
respect of the first six monthly greasy fleece weight where there was a large decline in F2 over
F, . On the contrary there was seen, quite a large increase in the second six monthly greasy
fleece weight in F2 over the F, . F2s were, however, superior in wool quality. Rambouillent x
Malpura halfbreds revealed 120% increase in greasy fleece production and almost 50%
improvement in wool quality. The survivability was also better in the halfbreds as compared to
the purebred natives. The Avikalin wool contains 58 S count and can be used for preparation of
medium quality apparel but because of its higher medullation percentage, it is better to use this
wool for making superior carpets.
Halfbreds produced from Corriedale, Dorset and Suffolk (Table 6.2) also offer promise
for augmenting quality carpet wool production.
Table 6.2 Average wool production and quality traits in crossbreeds being produced for
improving carpet wool production
Breed Annual greasy Fibre Staple Medullation Wool
fleece weight (kg) diameter (/µ) length (cm) (%) quality
Rambouillet 1.92 28.87 4.32 26.88 54S
Malpura
Suffolk x 1.74 32.48 5.18 59.05 48S
Malpura
Dorset x 1.77 35.25 6.60 66.03 44S
Malpura
Suffolk x 1.75 32.08 5.50 61.88 48S
Sonadi
Corriedale x 1.15 37.93 – 61.88 40S
Muzaffarnagri
Corriedale x 1.16 25.71 9.48 29.81 58S
Coimbatore
Corriedale x 0.70 30.30 4.24FL 46.67 50S
Nellore
Corriedale x 1.20 26.70 5.26FL 38.88 56S
Bellary
Wool quality referred to (S) quality number based on average fibre diameter alone. FL- Fibre Length.
The new synthetic produce more than 2.5 kg greasy wool annually. The Chokla
synthetioproduce 7.89% more wool than the purebred Chokla. The fibre diameter and
medullation percentage is decreased by 16.39 and 52.94% respectively. The Nali synthetic
produce more than 2.5 kg greasy fleece annually. The decrease in fibre diameter and
medullation percentage is of higher magnitude, viz. 19.93 and 62.03% respectively. In
reproduction and survival the two synthetics perform almost similar to the natives. The results
indicate that crossbreeding of Chokla and Nali with exotic fine wool breeds (Rambouillet or
Merino as the crosses arising from these two exotic breeds did not significantly differ in any of
the characters considered), stabilizing the exotic inheritance at 50% level and bringing further
improvement in greasy fleece weight and reduction in medullation percentage through selection
will allow improvement in fine wool production. The sampling of fleeces in this project for
determining fleece quality was done at 3 months of age, which gave higher medullation
percentage than at subsequent age, the difference being about 6-13 % between 3 month and 1
year of age. The two shortcomings in the new synthetics are lower staple length and presence of
medullated fibres. The medullated fibres are mostly heterotypes and will not create problems of
harshness in feel and dyeing. These can be removed through selection in the new synthetics.
These can also be taken care of by physico-chemical modifica tion through deposition of layer
of polymer. The staple length can also be increased through proper shearing regimen. Shearing
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