Sheep - AgRIS

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dwarfs (CC) to produce all comprest (Cc) because the mortality rate of the comprest dwarfs is so high that they do not survive to maturity and cannnot be used for breeding purposes. An important fact concerning selection when dominance is incomplete is that the genotype can be determined by inspection of the phenotype. Therefore, an undesirable gene can be eliminated from the herd by discarding all heterozygotes. 5. 5.3 Conformanon Desirable type and conformation have also received attention in sheep as in other classes of farm animals. With this species, however, attention must also be paid to selection for wool production in addition to mutton quality and rate and efficiency of gains. Animals possessing very obvious defects, such as over-shot jaws, undershot jaws, black wool, wool-blindness, skin folds, shallow bodies, and poor mutton qualities, should be culled from the flock. If animals with these defects are elimmated from the breeding lock and selections are made on the basis of body weight and quantity and quality of wool, especially in the selection of rams, perhaps this will amount to proper attention to type. Ewes which may be highly productive yet have some objectionable characteristic may be mated to a ram that is especially outstanding in the trait in which the ewes are inferior. Many times this corrects the fault in just one cross. This is a principle of mating that could be used to improve many traits and is effective, as shown by the history of the development of the many present-day breeds of farm animals. 5. 5.4 Wool and hair Types The main differences between hair and wool are: wool fibers are usually much smaller in diameter; the epidermal cells of hair are fastened to the cortex throughout their length; hair is always medulated; hair never is crimped like fine wool, although some is wavy like the coarser wools; both hair and wool may have pigment within the cortex, but most wool is free of pigment. Wool fibers grow much denser on the skin than hair grows. In vely dense-fleeced, fine-wool sheep there may be more than 50,000 fibers per square inch of skin area. In the coarser, loose fleeced sheep the number may not exceed 5,000 per square inch. Wool is one of the natural fibres of animal origin which is hygroscopic. It is a protein fibre and the protein is called Keratin because it contains sulphur bearing amino acids. The main sulphur containing amino acid cystein forms the basic linkage in wool through disulphide bonds. This fibre has a small diameter of the order of 103 to 10-4 compared to its length going upto 10-12 cm. This property gives it an important place among textile fibres. Its chemical constituents are mainly about 18-20 amino acids linked through CONH bonds forming the polypeptides which give softness and resiliency, suitable for a textile fibre. Also its surface structure, the cuticle has scales which provide cohesion in the fibres when they are twisted into yarn. The chemistry of the fibre is most suitable for easy dyeing nd other wet processes. Quality evaluation of textile materials is very important to utilize them for appropriate products. The properties of the yarn and fabric depend largely on the fibre arrangement and fibre properties. It is therefore important to know the fibre quality. The fleece in wild or less developed sheep breeds contains 3 types of fibres, viz. wool, hair and kemps. The true wool fibres are relatively fine and 15 to 50µ in diameter. Kemp fibres are very coarse (100 to 200µ) brittle, tapered, heavily medullated and short because of their limited growth. Hairy or hetertype fibres have a network of hollow, air-filled cell-walls (medulla). The medullated portion can be fragmented, interrupted or continuous. Medulla is commonly found in wools coarser than 30µ. The carpet wools are evaluated in terms of average fibre diameter, staple length and percentage of medullated fibres, viz. kemp and heterotypes. Variations in wool covering in different sheep are extremely large. Some sheep have wool fibers that are hard to distinguish from hair. In some, only the main portion of the body is covered, while in others the wool extends from just above the nostrils to the feet. Wool on any one sheep is never uniform in length or fineness. The finest and densest wool fibers are found on the shoulders, about midway between the top of the shoulders and floor of the chest; the coarsest wool is about the breech and dock, the shortest wool is usually on the belly. <strong>Sheep</strong> 369
with a dense growth of relatively long wool on the main parts of the body yield the heaviest fleeces. In the raw state, wool contains various adhering materials which may be considered as impurities. Some of these are not necessarily disadvantages as they may be essential to the proper preservation of the fiber while it is being developed to a length suitable for use. The amounts of these materials vary widely; the chief influences are those inherent in the sheep and those associated with environment, such as climatic and nutritional factors. The adhering materials consist of yolk, suint, vegetable matter, dirt, and moist.tre. In some cases these materials make up a greater percentage of the entire weight than does the wool fiber. The percentages for different kinds of wool may show such wide variations as follows: Variations in per eent of grease weight Wool fiber ............................................. 15 to 75 Yolk ........................................................ 7 to 40 Suint ....................................................... 5 to 15 Foreign materials .................................... 5 to 40 Moisture .................................................. 3 to 20 These figures are approximations taken from various sources and are intended merely to show what matters may influence the weight of raw wool obtained from a sheep. Furthermore, these amounts differ widely, depending upon what part of the fleece is selected for examination. Yolk or wool grease seems to be of direct importance in the preservation of the fiber from detrimental action by the weather. Wool that is lacking in yolk may show considerable damage, especially near the tip. On the other hand there is no apparent advantage in an amount of yolk beyond the minimum amount needed to afford such protection. The amount of yolk secreted by fine-wooled, densefleeced sheep is much greater than the amount found in the wool of loose, coarse-fleeced animals. Yolk is a mixture of a number of materials of which the principal one is cholesterol. This is not a true fat, and it does not form soap when combined with alkali. It is soluble in ether, alcohol and benzene. Much of it can be removed with water, with which it forms an emulsion. When purified, it has a number of uses in industry, such as in ointments, cosmetics, leather dressing, rope making, and rust preventive. Suint cannot be distinguished from yolk, as the two are mixed together in the grease found in raw wool. Suint is very different from yolk, however, as it is readily dissolved in water. Because of this and because it has emulsifying and cleansing properties, some consideration is given to its presence in wool scouring, and purified suint may be added to the scouring bowls. It consists chiefly of potassium salts of various fatty acids and lesser amounts of sulphates, phosphates, and nitrogenous materials. There has been no relationship reported between the suint and wool production. It seems to be the source of the odour associated with sheep. The dimensions of wool fibers vary from about 0.0003 to 0.002 inch for diarneter and from one to twenty inches in length during a year's growth. Crimp has been studied, and efforts have been made to determine what causes this character in wool. To date, no completely acceptable explanation has been given. Various means of classifying wool on the basis of crimp have been proposed; for instance, (a) normally crimped wool, (b) deeply crin-.ped wool, and (c) flat or wavy wool. Crimp is defined as that property which causes wool to assume its wavy appearance. It is much more pronounced in the wool of some breeds and some individuals than others. Variation in the kind of crimp in the fiber may indicate changes in the health of the sheep and, hence, differences in the strength and other features of the fibers. The number of crimps per inch of fiber ranges from about 10 to 36 per inch. The more numerous crimp are found in the finest wools, and this has given rise to the beliefthat numbers of crimp are definite indications of relative fineness. This is not strictly the case, although there is such a general relati znship, there are numerous exceptions. Coarse wool, such as obtained from Cotswolds or Lincolns, may have only one or two waves per inch. Crimp makes for great differences in the 370
Page 1 and 2: 1. Introduction ANNEXURE - IX-C SHE
Page 3 and 4: 2. Classification, Origin and Domes
Page 5 and 6: Nadu, Andhra Pradesh and Karnataka,
Page 7 and 8: different states it is estimated th
Page 9 and 10: Table 3.3 continued...... Country N
Page 11 and 12: een possible because of its substan
Page 13 and 14: (USA). The Rambouillet as purebreds
Page 15 and 16: ii) Marwari Deriving its name from
Page 17 and 18: Pradesh and Bihar, Bijapur, Gulbarg
Page 19 and 20: elatively tall with little hair exc
Page 21 and 22: 4.2 Distribution of type breeds in
Page 23 and 24: Table 4.1 continued...... Region/Br
Page 25 and 26: Table 4.2 continued....... SI. Bree
Page 27 and 28: 5. Genetics 5.1 Chromosome Profile
Page 29 and 30: esponsible for the formation of one
Page 31 and 32: the exercise these animals did not
Page 33: For understanding the inheritance o
Page 37 and 38: produced on rations which contain i
Page 39 and 40: The Coefficient of Variation The co
Page 41 and 42: 5.6.3 Wool Production/Wool yield an
Page 43 and 44: 6. Breeding 6.1 Components of Sheep
Page 45 and 46: elationships. Certain coat colors a
Page 47 and 48: Selection on this basis means that
Page 49 and 50: ii) Independent Culling Method In t
Page 51 and 52: eflected by increase in average fle
Page 53 and 54: at 75 or 8-4 monthly intervals comp
Page 55 and 56: Based on the crossbreeding results,
Page 57 and 58: Table 6.8 Means and standard errors
Page 59 and 60: month post-weaning individual feedl
Page 61 and 62: ams) in November, 1975 for evaluati
Page 63 and 64: een heavily fed and therefore may h
Page 65 and 66: need for one or more "teasers" to d
Page 67 and 68: ii) Consistency The normal consiste
Page 69 and 70: collection frequencies per day in 3
Page 71 and 72: iv) Altitude High altitude and poor
Page 73 and 74: 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 and 126:
The secretion of milk takes place d
Page 127 and 128:
with coarse and hairy breeds showed
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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