Sheep - AgRIS

10. Production Performance of Sheep
India possesses 40 breeds of sheep of which 5 can be classified into medium to fine wool
breeds, 24 into coarse carpet quality wool breeds and rest into hairy meat type breeds. The
average wool and meat yield per sheep in India is extremely low as compared to the same from
sheep in some agriculturally advanced countries. The problem of increasing productivity of
sheep in India centres around improving the yield of carpet quality wool and making it more
uniform, b) improving the mutton type yield of our native mutton breeds especially in the South
and c) developing new fine wool and mutton breeds through crossing our native breeds with
exotic fine wool and mutton breeds to suit the different agroclimatic regions of the country.
Similarly, knowledge about the consequences or cross breeding especially the heterosis
exhibited by crosses, level of exotic inheritance and the native and exotic breeds producing
crosses coming clossest to the desired goal, is necessary. The information available on exotic
and indigenous sheep indicate that except for fertility, all characters concerned with wool
production and wool quality as well as growth and carcass yield are highly heritable and most
of the genetic variability is due to the additive effects of genes.
To improve the genetic potential of the indigenous sheep, attempts through selection and
through crossbreeding have been made in the country. The Central Sheep and Wool Research
Institute, (CSWRI), Avikanagar, Rajasthan has been making efforts to improve the productivity
of Indian sheep through crossbreeding of indigenous breeds with exotic fine wool and mutton
breeds at the main regional stations and at the units under the All India Co-ordinated Research
Project, (AICRP) on sheep breeding located in different regions of the country
10.1 Studies on purebred performance
Purebred performance of important native breeds of sheep in the country has been studied
and it is observed that the performance of our native sheep for body weight gains, reproduction,
survival and greasy wool production is relatively poor as compared to the sheep in the
developed countries. But keeping in view the conditions of feeding and management in which
they are maintained they are not that inferior as it is apparent from the face value. Among the
breeds of north-western region, Magra can be considered to be the best whereas in the southern
peninsular region, Madras Red has been found to be superior to all other breeds in the region.
Based on the estimates of genetic and phenotypic parameters studied for different economic
characters, it is observed that six-month body weight is highly heritable and has positive
genetic correlation with market weight and adult body size and selection based on this weight
should improve market weight and the ewe productivity. Similarly, selection based on an index
combining greasy fleece weight and medullation percentage the latter being given a negative
weightage will improve the greasy wool production and quality in carpet wool breeds.
10.2 Studies on crossbreediogfor improving wool production and quality
Crossbreeding of indigenous breeds of various regions in the country, namely Gaddi in
temperate region, Chokla, Nali, Malpura, Jaisalmeri and Pattanwadi in North-western region,
and Nilgiri in the Southern hills with exotic fine wool breeds, namely Rambouillet and Russian
Merino has been tried. The results indicate major improvement in greasy fleece production at
half-bred level although there is improvement in fleece quality with increase in
Rambouillet/Merino inheritance beyond 50 per cent. It has thus been recommended that the
coarse wool breeds may be crossed with Rambouillett Russian Merino and the level of exotic
inheritance be limited to 50 per cent in north western region. In the northem temperate region
and southern hills, however, the inheritance level can be increased to 75 per cent because the
animals with this inheritance do not create any management problem and the improve ment in
wool to the finer quality which is evident at this level can be exploited to fill the gap of fine
wool in the country. For improving apparel wool production, research has been in progress
under a number of ICAR sponsored sheep improvement programmes at CSWRI and under the
AICRP on sheep breeding which have involved evaluation of different exotic fine wool breeds
and native breeds in crosses, level of exotic inheritance andeffect of interbreeding crossbreds.
Of the two exotic fine wool breeds, Rambouillet and Russian Merino in crosses, little
differences were seen in more extensive breeding experiments. However, in case of indigenous
breeds the superior carpet wool breeds showed improvement both in production and quality
parameters but brought the lesser wool reasonably closer to apparel wool whereas the crosses
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