Sheep - AgRIS

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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 461
with coarse and hairy breeds showed a larger improvement in greasy wool production and quality and brought the wool towards superior carpet quality at a different level. There was little increase in wool production with the increase in level of exotic inheritance and the halfbred had the maximum improvement. However, there was improvement in the quality as reflected by a decline in average fibre diameter and medullation percentage with increase in exotic inheritance. It was concluded that thehalf-breds involving exotic fine wool breeds and indigenous superior carpet wool breeds both in produc tion and adaptation as reflected by their grazing behaviour, capacity to trayel long distances and survival, are most suitable. Using this technology a new strain of sheep, viz, Avivastra have been evolved at CSWRI. This strain has been tested under conditions of grazing on reseeded cenchrus pasture without any feed supplementation and has shown excellent performance with respect to reproduction, lamb and adult survival, greasy wool production and quality. Avivastra produce 2.5 kg of annual greasy fleece weight of 21 micron fibre diameter and 21 per cent medullation and gives about 21 per cent higher income from the sale of wool alone compared to Chokla. Under the AICRP on sheep breeding two new synthetics/strains of fine wool—one with Chokla and the other with Nali have been generated at CSWRI. They produce more than 2.5 kg greasy fleece annually. The Chokla synthetic produce 7.89 per cent more wool showing 16.39 and 52.94 percent improvement in fibre diameter and medullation percentage respectively over the Chokla. The Nali synthetic produce marginally more wool and showing 19.93 percent improvement in fibre diameter and 62 per cent in medullation percentage over the Nali. Reproduction and survivability in both the synthetics and natives are not different. The synthetics produced the apparel type wool of 20 to 21 fibre diameter, with 0 to 5 per cent medullation and 5 cm staple length. Another fine wool strain viz Nilgiri synthetic has been evolved in Southern Hills at Sandynallah with annual production capacity of 3 kg having 18 micron average fibre diameter and 0 medullation. For improving carpet wool production, results available so far indicate that in case of coarse and hairy breeds, where the wool is not useful for quality carpets, the crossbreeding with superior fine wool breeds should be undertaken and the exotic inheritance be stablised at 50 per cent. It should be followed by selection for increasing carpet wool production and maintaining quality towards superior carpet wool (average fibre diameter 30 micron and 30 per cent partially medullated (heterotypic) fibres. The CSWRI has evolved a new superior carpet wool producing strain Avikalin through crossbreeding Malpura with Rambouillet stabilizing the exotic inheritance level at 50%. The superior carpet wool breeds such as Chokla, Nali, Magra, Patanwadi should be improved through selection is based on Six monthly greasy fleece weight and against medullation percentage. In other coarse and hairy breeds, where crossbreeding with exotic fine wool is not feasible, grading with better carpet wool breeds from Rajasthan namely, Nali and Magra be undertaken. The results of such grading have shown improvement in wool production and quality as reflected from an increase in staple length and decline in percentage of medullated fibres. 10.3 Sheep for mutton production The researches on crossbreeding conducted under the AICRP on sheep breeding for mutton units located in different regions of the country narnely CSWRI, Avikanagar, Rajasthan, Central Goat Research Institute, Makhdoom, Uttar Pradesh, Sheep Breeding Research Station, Palamper, Andhra Pradesh and Mahatma Phule Krishi Vrdyalaya, Rahuri Maharashtra involving different sheep breeds of the region with exotic mutton breeds, narnely Suffolk and Dorset indicate that half-breeds are superior to other grades with three-fourth and five-eighth inheritance in respect of performance as well as survivability. Pure indigenous breeds, though inferior in performance than crosses, have better survivability and lambing percentage. Suffolk crosses have higher mortality and low fertility and are superior to Dorset crosses in body weight gains. The halfbreds can attain 30 kg live weight at six months of age when fed under individual feed lot trials. Based on the performance of crossbred at 50 per cent and 75 per cent levels of exotic inheritance and combining ability with two exotic namely Suffolk and Dorset utilised in the crossbreeding programme, three mutton synthetics (strains), one at CSWRI and two at Palamner Unit under the AICRP of Sheep Breeding have been evolved. The synthetics/strains show superiority in feed lot grains, efficiency of feed conversion and to a small extent in dressing percentage on live weight basis over the indigenous breeds evolved. They attained live weight of 30 kg at six months of age under intensive feeding conditions, and are 60 per cent 462
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1. Introduction ANNEXURE - IX-C SHE
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2. Classification, Origin and Domes
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Nadu, Andhra Pradesh and Karnataka,
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different states it is estimated th
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Table 3.3 continued...... Country N
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een possible because of its substan
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(USA). The Rambouillet as purebreds
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ii) Marwari Deriving its name from
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Pradesh and Bihar, Bijapur, Gulbarg
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elatively tall with little hair exc
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4.2 Distribution of type breeds in
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Table 4.1 continued...... Region/Br
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Table 4.2 continued....... SI. Bree
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5. Genetics 5.1 Chromosome Profile
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esponsible for the formation of one
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the exercise these animals did not
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For understanding the inheritance o
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with a dense growth of relatively l
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produced on rations which contain i
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The Coefficient of Variation The co
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5.6.3 Wool Production/Wool yield an
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6. Breeding 6.1 Components of Sheep
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elationships. Certain coat colors a
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Selection on this basis means that
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ii) Independent Culling Method In t
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eflected by increase in average fle
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at 75 or 8-4 monthly intervals comp
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Based on the crossbreeding results,
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Table 6.8 Means and standard errors
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month post-weaning individual feedl
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ams) in November, 1975 for evaluati
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een heavily fed and therefore may h
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need for one or more "teasers" to d
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ii) Consistency The normal consiste
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collection frequencies per day in 3
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iv) Altitude High altitude and poor
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containing diluents enriched with a
Page 75 and 76: 6. Nutrients Although spermatozoa u
Page 77 and 78: 7. 3.1 Puberty Puberty in the femal
Page 79 and 80: Estrogen in large quantities inhibi
Page 81 and 82: The udder becomes firm and enlarged
Page 83 and 84: 7. 3. 8 Interlambing interval It is
Page 85 and 86: 8. Nutrition 8.1 Components of Shee
Page 87 and 88: allied to the various amino acids o
Page 89 and 90: animals. A deficiency of salt is sh
Page 91 and 92: seem to have most significance in s
Page 93 and 94: Table 8.2 Chemical composition of g
Page 95 and 96: Table 8.3 Nutritive value of fodder
Page 97 and 98: Mineral and vitamin Requirement If
Page 99 and 100: Table 8.5 Total digestible nutrient
Page 101 and 102: Table 8.7 continued....... c) Lacta
Page 103 and 104: shirinking due to reclaimation of l
Page 105 and 106: Sorghum-Berseem-Maize Improved vari
Page 107 and 108: 9. Housing and Management 9.1 Syste
Page 109 and 110: ) Shearing, skirtng and primary cla
Page 111 and 112: The availability of pastures which
Page 113 and 114: fodder as green or hay, concentrate
Page 115 and 116: 9.2.2 Lambs Efforts should be made
Page 117 and 118: Mortality in young lambs and other
Page 119 and 120: land and they depend on the forest
Page 121 and 122: age and fed intensively till they a
Page 123 and 124: Overnight teasing and drafting ridd
Page 125: The secretion of milk takes place d
Page 129 and 130: 11. Sheep Production System in Diff
Page 131 and 132: 12. Wool Production and quality 12.
Page 133 and 134: crosses with Dorset and Merinos, Pa
Page 135 and 136: 13. Meat Production 13.1 MeatProduc
Page 137 and 138: Table 13.1 Mutton (sheep) productio
Page 139 and 140: 14.4 Utilization of milk Sheep are
Page 141 and 142: one crushing mills and about 360 bo
Page 143 and 144: 16. Sheep Records It is essential t
Page 145 and 146: 17. Diseases and their Control Morb
Page 147 and 148: Atropin sulphate 2.0 mg/kg. body we
Page 149 and 150: contents by neutralization tests wi
Page 151 and 152: prophylactic, foot and mouth vaccin
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Sheep - AgRIS

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