Sheep - AgRIS

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are capable of producing two kinds of lambs with respect to their color appearance. They may be white or black. But there will be three kinds of lambs with respect to their genetic make-up. White is dominant over black, and there may be lambs that are pure or homozygous for white, heterozygous for white and black, and others that are pure for black. Since black is a recessive color in most of our common sheep, only lambs that are pure for black have a black color. Therefore, if a black lamb is horn it gets that character equally from both parents. The same processes are involved with respect to all characters that are due to single genes. If a ram was homozygous for all characters he possessed, his offspring from ewes that had dissimilar characters could not possibly be homozygous. Thus, the only way to maintain a homozygous condition once it has been developed is to restrict mating to individuals that are homozygous. Mating brother and sister does not in itself insure progeny that is homozygous. Even with a homozygous condition with respect to the genes, it would be improper to expect all progeny to be exactly alike, for some characters that are to be found in individuals are due to physiological reactions, which of course may in turn be related to the genes which have been transmitted from the parents. Horns are undoubtedly an inherited character, but certain physiological processes or substances must be present for the inheritance to become evident. It is possible that physiological processes are influenced by the interaction of various genes. Some characters are due to single genes, but not all the characters. Some are due to two or more genes where the degree of interaction may vary. Dominance may not always be complete, and partial dominance introduces more complexity. Likewise, there are cases when a character may be dominant in one sex but not in the other. 5.2 Blood Groups Systematic studies on blood groups of Indian sheep were conducted by Raina (1969). All antibodies were observed in normal sera of group O sheep and were used as reagents for detecting R blood-group factor on sheep erythrocytes. The anti-O antibodies were found in normal sera of two out of 89 sheep tested and were used as reagents. The highest titres of anti-R and anti-O were found around September and lowest around March-May. The erythrocytes of new-born lambs lacked the R and O subKstances, though these antigens were present in the respective blood sera. Twenty-seven blood-group factors belonged to nine different blood-group systems, of which A,B,C, M and R-O systems were previously described, and F,G,H and K systems were the new bloodgroups systems not reported earlier. Fourteen blood-group factors were recognized in the B-system, where 51 alleles were recognized. Twelve C pheno-groups controlled by 12 different alleles were recognized in the C system. A system was observed to have two alleles giving two distinct phenotypes. The l\iystem also had 2 alleles giving Z distinct phenotypes. 5.3 Biochemical Polymorphism 5. 3.1 Haemoglobin Indian sheep show normally three distinct haemoglobin (Hb) phenotypes, viz. AA, BB and AB resulting from two alleles A and B (Agar 1969,Agar and Evans 1969 a,b, Agar et al. 1969, Kalla et al. 1970, Arora 1970, Arora et al. 1970 a, Agar and Seth 1971, Singh et al. 1972 a,b, Singh et al. 1976 a, b, Arora and Arora 1978, Kandesamy 1979 and Arora 1979). Another type i.e. Hb C has also been reported in a highly anaemic Nali lamb (Arora et al. 1970 b). The gene frequencies of haemoglobin types in various breeds in India are given in Table 20.1. In Indian breeds, individuals with Hb B predominated. Indian meat types breeds (Nellore and Mandya) and their crosses with Indian carpet wool breeds and exotic mutton breeds (Suffolk and Dorset) and their crosses with Malpura and Sonadi show a higher frequency of Hb B type. In some breeds of hilly region the frequency of Hb A is found more. Haemoglobin types are inherited in simple Mendelian fashion. The two haemoglobin types, viz. Hb A and Hb B are controlled by two alleles codominant to each other, each 363
esponsible for the formation of one kind of haemoglobin although some deviation from the general rules has also been observed by Fesus (1972) and Singh et al. (1972 b). Haemoglobin polymorphism has been studied extensively in Indian sheep breeds. Arora and Acharya (1972) found no significant effect of haemoglobin types on body weights at birth, and 3,6,9 and 12 months of age in Nali sheep, although the individuals with HbBB phenotypes were marginally better at birth, 6 months and yearling age than HbAB phenotypes. Seth et al. (1974) observed the influence on growth with HbAB showing significantly higher weights. Arora (1980) also found HbAB type to be superior at 9-month body weight. Trivedi and Bhat (1978) did not observe any relationship between haemoglobin types and growth. Kalla et al. (1971) showed that animals of HbAA type were better as regards the quality of wool produced than the animals of HbAB and HbBB type. Kalla and Ghosh (1975) also observed Hb type to be better in fleece production per kg live weight. Arora and Acharya (1972) observed no significant difference of Hb types on first six monthly greasy-fleece weight in Nali sheep. However, the HbBB type individuals were only Inarginally superior to HbAB individuals. Similar non-significant results about the effects of Hb types on wool traits were found by Chopra and Chopra (1972) in Nali and Lohi sheep. Bhat et al. (1981) observed that haemoglobin types had significant effect on average fibre diameter in Gaddi breed of sheep. HbAB type individuals had significantly finer fibre diameter than those of HbBB type individuals. 5. 3.2 Transferrin The available infomlation about Indian breeds is meagre. Arora and Acharya (1971a) observed nine transferrin tvpes Tf I , Tf A , Tf G , Tf B , Tf C , Tf M , Tf D , Tf E and Tf P in Nali, Lohi, Nali x Nellore7 Lohi x Nellore and Nali x Mandya. Gene frequency was highest for Tf C , Tf D , Tf B and Tf M . Shamma et al. (1976) and Trivedi and Bhat (1978) reported transferrin polymorphism in Muzaffamagari breed of sheep and its cross with Corriedale and Suffollc and Dorset. Transferrin alleles TfA, Tfii, TS, Tfi', and Tfii were observed. Frequency of Tf B and Tf D was highest. Negi and Bhat (1980) observed five transferrin alleles Tf A , Tf B , Tf C , Tf D and Tf E in Gaddi breed and its crosses with Russian Merino and Rambouillet. Frequency of Tf B and Tf D was highest in Gaddi while frequency of Tf D and Tf A was highest in crossbreds. Arora and Acharya (1972) observed significant variation between transferrin types in yearling weight of Nali and Lohi sheep and their three crossbreds (Nali x Nellore, Lohi x Nellore and Nali x Mandya). <strong>Sheep</strong> of Tf MB type had the highest yearling weight followed closely by those of Tf EC Birth weight was highest in lambs with Tf EM , whereas 3-month weight was highest in sheep of Tf EE type. Animals of Tf EM type had the highest 6-month weight. Transferrin type explained about 5 per cent of the variation in birth weight and 15 per cent of that in yearling weight. Sharma et al. (1978), Bhat et al. (1978, 1981) and Trivedi and Bhat (1978) also observed significant effect of transferrin types on body weights at different ages. Bhat et al ( 1981) observed that transferrin types had a significant effect on fleece yield in Gaddi breed of sheep. Animals of Tf AD type had a significantly higher fleece weight than the other types. 5. 3.3 Albumin Krishnamurty et al. (1974) observed anew albumintype slower than S in Macheri breed of Indian sheep. Bhat (1978) did not observe any polymorphism in respect of serum albumin in Muzaffarnagari breed of sheep. Negi and Bhat (1980) reported similar results in Gaddi breed of sheep. 364
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: 5. Genetics 5.1 Chromosome Profile
Page 31 and 32: the exercise these animals did not
Page 33 and 34: For understanding the inheritance o
Page 35 and 36: with a dense growth of relatively l
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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