Browsing by Author "Anilkumar, K"

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Delineation of random amplified polymorphic DNA markers in crossbred cattle
(Department of Animal Breeding and Genetics, College of Veterinary and Animal Sciences, Mannuthy, 2003) Anilkumar, K; Raghunandanan, K V
Evaluation of microsatellite markers for selection of crossbred cattle
(Department of Animal Breeding and Genetics, College of Veterinary and Animal Sciences, Mannuthy, 2005) Naicy Thomas; Anilkumar, K
The possibility of using the informations of the allele frequency, genotype frequency, heterozygosity and PIC of five selected microsatellite markers (ILSTS096, HUJII77, BL41, BM1508 and BM4305) and their associations with the economically important traits for the selection of crossbred cattle were studied. Among the economic traits studied milk fat percentage and AFC showed significant difference among the ten sire families and hence their associations with the selected microsatellite markers were worked out. PCR conditions were standardised for each marker separately. The number of alleles, size range and number of genotypes identified were 12, 188-212 bp and 35 respectively for ILSTS096 locus, 13, 193-221 bp and 36 for HUJII77 locus, 14, 232-266 bp and 36 for BL41 locus, 7, 103-115 bp and 17 at BM1508 locus and 12, 146-168 bp and 37 for BM4305 locus in the unrelated crossbred dairy cattle population. The highest direct count heterozygosity was obtained for ILSTS096 followed by BL41, BM4305, HUJII77 and BM1508 (0.877-0.683). The highest unbiased heterozygosity was obtained for ILSTS096 followed by BL41, BM4305, HUJII77 and BM1508 (0.880-0.686). All the markers were highly informative as their PIC values (0.865-0.630) were more than 0.5. Three sire families namely, Deva, Bull No.250 and Hakkim showed significantly lower milk fat percentage and three other (Dipesh, Onkar and Gopal), showed significantly higher AFC. All the five microsatellite markers had significant effect on milk fat percentage and three of them (ILSTS096, BL41 and BM4305) showed significant effect on AFC. The allelic averages of fat percentage for the allele 188 and 204 at ILSTS096 locus, 205 at HUJII77 locus and 154 at BM4305 locus were significantly lower and that of 198 at ILSTS096 locus, 240 at BL41 locus, 109 and 113 at BM1508 locus and 166 at BM4305 locus were significantly higher. The allelic averages of AFC for the alleles 196 at ILSTS096 locus, 246 at BL41 locus and 154 at BM4305 locus were significantly lower. All these three alleles were absent in the sires of the three families having higher AFC. The allelic frequencies of 188 and 204 of the marker ILSTS096 were low in the population and that of 198 was high. So selection against the alleles 188 and 204 and selection for the allele 198 can be done, but the impact of selection will be meagre. At the BL41 locus, frequency of the allele 240 was comparatively low and the frequency of the allele 242 is very high in the population. So the selection for the allele 240 and selection against the allele 242 will have good impact on milk fat percentage of the selected animals. Frequency of allele 246 in the population is comparatively low. Hence selection for this allele will be favourable to reduce the AFC. The frequency of the allele 109 of BM1508 is low. So selection for this allele will be more beneficial. The animals with the allele 166 at BM4305 locus had the highest average of milk fat percentage and the frequency of this allele in the population is very low, hence selection for this allele will have good impact on higher milk fat percentage.
Genetic characterisation of buffaloes in Kerala using cytogenetic technique
(Department Of Animal Breeding And Genetics, College Of Veterinary And Animal Sciences, Mannuthy, 1991) Anilkumar, K; Mukundan, G
Buffaloes from four districts of Kerala formed the materials for this study. Blood samples were collected from external jugular/ear vein, in heparinised tubes. The technique employed was peripheral leukocyte culture technique. Out of the three different mitogens viz., pokeweed mitogen (PWM), phytohemaggultinin (PHA). and a mixture of these two. the mixture of PWM and PHA was found superior in inducing mitosis. A significant interaction between the mitogens and time of addition of mitotic arrester into the medium was observed. The mixture of PWM and PHA at an incubation time of 71 hours was found to produce best results in culture of buffalo lymphocytes followed by PWM at 70 hours. Ideal concentration of colcemid as mitotic arrester in this study was found to be 2 µg and 3 µg per ml of culture media, when the time of action of colcemid was retained for one hour. Out of the 54 animals studied 45 had 2n=50, 5 had 2n=48 and rest 4 had 2n=49. In all the three chromosome types of animals 10 submetacentric chromosomes were observed. The sex chromosomes were similar in all the three types. Number of acrocentric autosomes was 38, 36 and 37 in the three classes respectively. The buffaloes having diploid chromosome number of 49 had two non homologues submetacentric chromosomes, one being the largest of the whole complement and one acrocentric was without a pair. The longest submetacentric autosome of swamp type had a relative length of 6.925+0.152 whereas in river type it had a relative length of 7.228+0.094. The smallest submetacentric autosome was having an average relative length of 4.911+0.118 and 5.05+0.107 in swamp type and river type respectively. Relative lengths of longest acrocentric autosome in swamp type and river type were) 4.953+0.13 and 4.618 + 0.095 respectively. The shortest acrocentric in swamp type showed a relative length of 2.301+0.034 whereas in river type the shortest chromosome had a relative length of 2.064+0.275. The X chromosome was largest acrocentric chromosome of the complement. The Y chromosome was acrocentric and took a position of 22 in descending order based on relative length in the river buffaloes, whereas it occupied 20th position in swamp type. The X chromosome in swamp type had the relative length of 6.228 + 0.099 and that of river type was 6.220+0.136. The Y chromosome of swamp type and river type had relative length of 2.675+0.188 and 2.550+0.095 respectively. In terms of relative length X chromosome occupied fourth position in comparison to submetacentric autosomes of river type, whereas it was third position in swamp type. In swamp buffaloes arm ratio ranged from 1.479+0.055 in fifth to 2.183+0.169 in first submetacentric autosome. In river type the largest arm ratio was 2.289+0.221 in first chromosome and the smallest was 1.542+0.158 in fifth chromosome. The highest centromere index of 40.4+0.9 was obtained for fifth chromosome and the smallest centromere index of 33.2 + 2.1 was for first chromosome of swamp type. In river buffaloes fifth chromosome had a centromere index of 40.4+1.9 and first chromosome had the centromere index of 31.2+2.4. The observation of chromosome polymorphism in buffaloes of Kerala State have to be borne in mind prior to drawing breeding strategies in buffaloes for improved production potential and productive efficiency.
Molecular genetic diversity in dwarf cattle of Kerala
(Department of Animal Breeding and Genetics, College of Veterinary and Animal Sciences, Mannuthy, 2003) Suprabha, P; Anilkumar, K
Muyal valarthal
(Kerala Agricultural University, Vellanikkara, 2011) Anilkumar, K