Browsing by Author "Mukundan, G"

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Biochemical polymorphism in broiler rabbits
(Department of Animal Breeding, Genetics and Biostatistics, College of Veterinary and Animal Sciences, Mannuthy, 1990) Usha, A P; Mukundan, G
Blood samples collected from rabbits maintained in the rabbit breeding farm of Kerala Agricultural University formed the materials for this study These blood samples were typed employing horizontal polyacrylamide gel electrophoresis to study the polymorphism of transferrin post transferrin and haemoglobin A total of 152 rabbits comprising of 50 Soviet Chinchilla 52 Newzealand White and 50 local rabbits were involved m the study Genetic inter relationship among growth traits and survivability were studied In all the genetic groups two transferrin variants the faster Tf and slower Tf with two phenotypes TfAA and TfAC were observed The gene frequency of Tf and Tf were 0 7500 and 0 2500 in Soviet Chinchilla 0 8300 and 0 1700 m Newzealand White and 0 8100 and 0 1900 m local rabbits The frequency of TfA allele was higher in all the populations The phenotype TfCC was not observed in any of the genetic groups Three post transferrin phenotypes Ptf FF Ptf FS and Ptf SS were detected and found to be controlled by two F S co dominant alleles Ptf and Ptf The fast moving F variant was designated as Ptf and the slow moving migrant S F was designated as Ptf The gene frequency of Ptf was 0 7400 0 8500 and 0 7600 m the three genetic groups and e that of Ptf was 0 2600 0 1500 and 0 2400 in Soviet Chinchilla Newzealand White and local rabbits respectively Haemoglobin was found to be monomorphic in all the three genetic groups studied The allelic frequencies of transferrin and post transferrin were suggestive of Hardy Weinberg equilibrium in the populations of three breeds No significant diversity was found to exist between genetic groups analysis of segretation pattern observed in pedigrees revealed the autosomal codominant mode of inheritance for transferrin and post transferrin alleles The absence of TfCC phenotype in the whole population of rabbits may be due to its unfavourable influence on the viability
Blood group and biochemical polymorphism in the Malabari breed of goat and its exotic crosses
(Department of Animal Breeding and Genetics, College of Veterinary and Animal Sciences, Mannuthy, 1989) Nandakumaran, P; Mukundan, G
Realising the importance of blood groups and biochemical polymorphism in livestock improvement a study was undertaken in 305 adult goats of Malabari breed and its exotic crosses viz. Saanen x Malabari and Alpine x Malabari, to identify the blood group factors and polymorphism, if any, at haemoglobin, potassium and erythrocyte glutathione (GSH) loci and their utility as genetic markers for selection. Standard haemolytic test and absorption technique were performed to produce monovalent reagents and to type the goats. The different haemoglobin types were detected employing horizontal starch gel electrophoresis. The potassium concentration in whole blood and the GSH concentration in erythrocytes were estimated by Flamephotometry and Spectrophotmetry respectively. Twelve blood group reagents M1, M2, M3, M4, M5, M6, M7, M8, M9, M10, M11 and M12 were produced during the present study from the nineteen polyvalent goat sera obtained from Switzerland. The phenotypic frequencies of different blood group factors were different from each other among the three genetic groups. The blood group factors M4, M10 and M12 were not observed in the Malabari goats. In electrophoretic separation, 94 per cent of the goats showed only one haemoglobin band (HbAA) and six per cent showed two bands (HbAB). HbBB was not observed in any of the genetic groups. Inheritance pattern of Hb alleles revealed that they inherit as autosomal co-dominant alleles. The frequency of HbA allele was 0.98 in Malabari and Saanen x Malabari and 0.97 in Alpine x Malabari, the difference being non significant. It was observed that the goat populations were in Hardy-Weinberg equilibrium with respect to the haemoglobin locus. The genetic group had no effect on the concentration of whole blood potassium. The frequency distribution of potassium concentration in the pooled population showed a distinct bimodality, on the basis of which the goats were classified into two distinct types viz. LK ( < 22 meq/1) and HK ( > 22 meq/1). 76.39 per cent of the pooled population were the LK type, a situation not reported in Indian goats. The potassium phenotypes are controlled by two autosomal alleles, KL (determining LK) and KH (determining HK), the KL being dominant over KH. The gene frequencies of KL and KH were 0.53 and 0.47 in Malabari, 0.50 and 0.50 in Saanen x Malabari and 0.52 and 0.48 in Alpine x Malabari, the difference among the three genetic groups being non significant. The genetic groups had significant effect on the potassium concentration in LK type goats, but such effect was not noticed in HK type goats. The genetic groups had significant effect on the erythrocyte glutathione (GSH) concentration. The frequency distribution of GSH concentration in the pooled population revealed a bimodality. Goats with GSH concentration of > 60 mg/100 ml RBC were classified as GSH-high type and those with < 60 mg/100 ml RBC were classified as GSH-low type. The frequency percentage of GSH-high type in the pooled population was 85.26. Among the three genetic groups, Alpine x Malabari had the highest frequency of 88.48 per cent and Malabari had the lowest frequency of 76.56 per cent. Inheritance pattern of GSH phenotypes showed that in goats GSH types are controlled by two autosomal alleles GSHH (determining GSH-high type) and GSHh (determining GSH-low type), the GSHH being dominant over GSHh. The frequencies of GSHH and GSHh were 0.51 and 0.49 in Malabari, 0.62 and 0.38 in Saanen x Malabari and 0.66 and 0.34 in Alpine x Malabari, without any significant differences among the genetic groups. The frequencies of potassium and GSH alleles and also their concentration did not change over the two generation in any of the genetic groups except in Saanen x Malabari, wherein the mean GSH concentration GSH-high type goats of third generation was significantly higher than that of the second generation. Sex did not influence the concentration of potassium and GSH. A valid conclusion could not be drawn on the effect of sire on the potassium and GSH concentration in its offspring. Studies revealed that haemoglobin, potassium and GSH were not genetically associated. Haemoglobin type had no effect on packed cell volume and concentration of potassium and GSH. The LK type goats had significantly higher packed cell volume in all the genetic groups. The potassium type had no effect on the concentration of GSH in the crossbred goats but in Malabari the HK types had significantly higher concentration in GSH than that of LK types. Goats with HbAA phenotype had heavier body weight at different ages when compared to that of HbAB type. However, the differences was significantly only for the weight at one year in Malabari and weight at nine months in crossbreds. Haemoglobin type had no effect on the production traits. In general, the growth and production traits were not seen influenced by the potassium and GSH types.
Chromosome profile of Indian elephants ( Elephas maximus indicus)
(Department of Animal Breeding and Genetics, College of Veterinary and Animal Sciences, Mannuthy, 1988) Sakthi Kumar, A; Mukundan, G
A karyological study in Indian elephants using peripheral venous blood collected from 7 tuskers, 7 cow elephants and one makhna belonging to some temples and private owners of Trichur District was undertaken with objectives of a) to evolve a technique for chromosome studies of elephants. b) to find out the chromosome number in Indian elephants, and c) to suggest sex chromosome mechanism in sex determination. Standardization of technique Comparison of efficacy of phytohaemagglutinin – M (Difco) and Poke – weed mitogen (GIBCO), in two different culture media namely TC 199 and RPMI – 1640, as mitogens showed that phyto – haemagglutinin – M yielded a mitotic index of 0.33 and 0.66 per cent in medium TC 199 and RPMI – 1640 respectively; poke – weed mitogen yielded a mitotic index of 5.33 and 5.66 per cent respectively in TC 199 and RPMI – 1640. Statistical analysis revealed that the efficacy of the two different media used was not significantly different, whereas the efficacy of two mitogens differed significantly at five per cent level. Poke – weed mitogen was found to be better than phytohaemagglutinin – M as far as indusing mitoses in elephant lymphocyte cultures over a 72 hour culture period was concerned. Colchicine treatment using 0.1 ml colchicine solution (0.0001%) for a period of one hour yielded satisfactory chromosome preparations. Karyotype The karyotype of the tusker, cow elephant and makhna revealed a diploid chromosome number of 2n = 56, comprising of 54 autosomes and 2 sex chromosomes. The autosomes were classified into 6 submetacentric and 21 acrocentric chromosomes. The X – chromosome was a submetacentric in all the three groups of elephants whereas the Y – chromosome was a small acrocentric in the tusker as well as the makhna. Analysis of relative length of chromosomes showed that the largest chromosome pair measured a relative length of 6.973 per cent and the smallest chromosome was the Y – chromosome measuring a relative length of 1.710 per cent. Position of centromere on the basis of centromeric index suggested that the centromere was farthest from the centre of the chromosome in the second autosome pair and nearest to the centre in the X – chromosome among the submetacentric chromosomes. Neither autosomes nor sex chromosomes possessed satellites on karyological examination. The elephants studied exhibited XX/XY sex chromosome mechanism. The cow elephant possessed XX sex chromosome complement while both tusker and makhna possessed XY sex chromosome complement. A comparison between the karyotypes of tusker and makhna did not show any variation in (a) basic number, (b) relative length (C) position of centromere, (d) absence of satellites on the chromosomes and (e) the sex chromosome complement. It may be concluded that tusklessness in makhna is not associated with either euploidy or aneuploidy.
Chromosome profile of zebu x taurus cattle in Kerala
(Department of Animal Breeding and Genetics, College of Veterinary and Animal Sciences, Mannuthy, 1988) Raghunandanan, K V; Mukundan, G
Evaluation of lactation performance of Zebu x Taurus cattle in Kerala
(Department of Animal Breeding and Genetics, College of Veterinary and Animal Sciences,Mannuthy, 1983) Stephen Mathew; Mukundan, G
An investigation was undertaken to evaluate the lactation performance of the crossbred cattle (Zebu x Taurus) and to compare the performance of Brown Swiss and Jersey crosses under field conditions so that a breeding policy could be recommended. First lactation milk yield in 305 days, age at first calving and first lactation length were the characters studied. For this, data on the Brown Swiss crossbred maintained by the farmers at Mavelikkara and Kattappana and on Jersey crossbreds at Kanjirappally and Chalakudy under the milk recording – cum – progeny testing scheme of the Kerala Livestock Development and Milk Marketing Board were utilized. The observations spread over a period of four years from 1978 to 1981. The uncorrected average first lactation yields were 1508.8 + 14.3 kg in Brown Swiss half – breds, 1562.6 + 28.7 kg in unclassified Brown Swiss crosses, 1380.3 + 47.0 kg in Jersey half – breds and 1558.0 + 31.5 kg in unclassified Jersey crosses. The least squares means of first lactation yields in Brown Swiss half – breds, unclassified Brown Swiss crosses, Jersey half – breds and unclassified Jersey crosses were 1482.0 + 19.7 kg, 1544.7 + 32.4 kg, 1359.2 + 57.4 kg and 1559.8 + 37.3 kg respectively. The Duncan’s multiple range test showed that the Jersey half – breds had significantly lower production compared to all other genetic groups. The production of unclassified Jersey crosses had been significantly higher than the Brown Swiss half – breds as well as Jersey half – breds. Least squares analysis on pooled data and Brown Swiss half – breds showed the significant influence of age at first calving, year of calving and sex of the calf on first lactation milk yield. But, season of calving did not significantly influence the milk yield. The uncorrected average age at first calving in Brown Swiss half – breds, unclassified Brown Swiss crosses, Jersey half _ breds and unclassified Jersey crosses were 46.0 + 0.4 months, 38.4 + 0.6 months, 41.7 + 1.4 months and 39.5 + 1.2 months respectively. The least squares means of age at first calving in Brown Swiss half – breds, unclassified Brown Swiss crosses, Jersey half – breds and unclassified Jersey crosses were 46.0 + 0.5, 38.0 + 0.8, 41.1 + 2.1 and 38.9 + 1.5 months respectively. Brown Swiss half – breds had significantly higher age at first calving compared to the other three groups which were homogenous. The effect of year on age at first calving was not significant in Brown Swiss half – breds while pooled data analysis showed a significant effect of year on age at first calving. The uncorrected average lactation lengths in Brown Swiss half – breds, unclassified Brown Swiss crosses, Jersey half – breds and unclassified Jersey crosses were 300.5 + 0.5 days, 299.6 + 1.0 days, 295.6 + 2.4 days and 295.3 + 1.7 days, respectively. This shows that all the crossbreds had fairly good lactation length. Lactation milk yield and age at first calving are economically important to the farmer and in this context these two characters are to be considered together. The results obtained do not indicate the superiority of either Brown Swiss or Jersey crossbreds, over the other. The introduction of both Brown Swiss and Jersey improved the milk production of the cattle of Kerala. While aiming at a further improvement, emphasis should be given to the merit of the sires rather than the specificity of the exotic breed or the percentage of exotic inheritance.
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.
Genetic studies on polymorphism of some blood Proteins in goats
(Department of Animal Breeding and Genetics, College of Veterinary and Animal Sciences, Mannuthy, 1984) Shamsuddin, A K; Mukundan, G
Blood samples collected from goats maintained in the farm under All India coordinated Research Project on Goats for Milk of Kerala Agricultural University, Mannuthy, formed the materials for this study. These blood samples were typed employing horizontal starch – gel – electrophoresis to study the polymorphism of haemoglobin, transferrin, albumin and amylase. In all 188 goats comprising 40 Malabari, 72 Saanen x Malabari (halfbred) and 76 Alpine x Malabari (halfbred) were involved in the study. Inter and intra population variability was studied. Genetic interrelationship among some growth, production and reproduction traits viz. body weights at birth, 3 months, 6 months and 12 months, age at first kidding, first lactation yield (120 days), peak yield and interkidding interval was determined. Two haemoglobin variants, the faster HbA and slower HbB with two phenotypes HbAA and HbAB were observed. The gene frequency of HbA in Malabari, Saanen halfbred and Alpine halfbred goats was 0.9750, 0.9792 and 0. 9671 respectively and that of HbB in these three genetic groups was 0.0250, 0.0208 and 0.0329 respectively. The frequency of HbA allele was higher in all the populations. Four transferrin phenotypes TfAA, TfAB, TfBB and TfAC controlled by three co – dominant alleles TfA , TfB and TfC were observed. The fast moving variant was designated as TfA followed by TfB and TfC. In Malabari goats TfAC was not observed. The frequency of TfAB type was higher in all the genetic groups. The gene frequencies of TfA, TfB and TfC in Malabari goats were 0.4500, 0.5500 and zero respectively. TfC allele was not observed in Malabari goats. Three Tf alleles namely TfA, TfB and TfC were revealed in the crossbred populations with a preponderance of TfA allele. The frequencies of TfA, TfB and TfC alleles in Saanen halfbreds were 0.5278, 0.4236 and 0. 0486 and in Alpine halfbreds were 0.5329, 0.4539 and 0.0132 respectively. The allelic frequencies of haemoglobin and transferrinloci were suggestive of Hardy – Weinberg equilibrium in all the three population or goats. Magnitude of inter population variability among the three genetic groups was negligible. The autosomal co – dominant mode of inheritance for Tf alleles was demonstrated by analysis of segregation patterns observed in pedigrees. Significant association was observed between the TfAA phenotype and economic traits such as birth weight, first lactation yield and peak yield. Polymorphism was not observed for the albumin and amylase systems. Maximum heterozygosity was observed at the transferrin locus. Highest average heterozygosity was exhibited by the Saanen halfbred goats. Among the four biochemical of blood studied, transferrin reflected a great scope for serving as a genetic marker to be used in selection of goats for improved milk production.
Genetic studies on the immune response of broiler rabbits
(Department of animal breeding and genetics, College of veterinary and animal sciences, 1995) Nandakumar, P; Mukundan, G
Genetics analysis of body weight and litter traits of pure bred rabbits
(Department of Animal Breeding and Genetics, College of Veterinary and Animal Sciences, Mannuthy, 1992) Radhakrishnan, J; Mukundan, G
The experiment was carried out at the Rabbit Research Station attached to the Centre for Advanced Studies in Animal Genetics and Breeding, Mannuthy. Rabbits belonging to three pure breeds viz. Grey Giant, Soviet Chinchilla and New Zealand White formed the materials for the study. From each breed, seven males were taken and each male was mated to two females each and in all 14 females and seven males were considered in each breed. Seven parameters of reproductive efficiency of the dam were taken and body weights of rabbits born were recorded at four, six, eight, ten and twelve weeks of age. The mean values of body weight at four, six, eight, ten and 12 weeks were highest in Soviet Chinchilla rabbits compared to Grey Giant and New Zealand white, which had the lowest weights among the three breeds. Breed effect was significant for the body weight in all the weeks. The effect of sex on the body weight of rabbit was non – significant in all the three breeds. The sire of the offspring affected the body weight at each stage in all the three breeds. There was also a dam effect on body weight. In general the estimates of heritability were high in all the three breeds. The estimates of heritabilities for body weight show some marked effects of age. In particular, the pre – weaning weights had a high or moderate value compared with the lower estimates obtained for post – weaning weights. Estimates of heritability from the dam component revealed generally larger heritabilities than those of sire component except in New Zealand White rabbits. The phenotypic correlations between the body weights at different ages were positive and generally high, and tended to decrease in value as the differences between the two ages increased. The genetic correlations between body weights for the three breeds showed that all of these relationships were positive, like the corresponding phenotypic estimates. The environmental correlations were generally very high in all the three breeds except in Grey Giant rabbits when estimated based on (Sire + dam) method which may be due to sampling error. It was found that the effect of the breed on the gestation length was non – significant. The breed of the rabbit significantly affected the litter size at birth. Soviet Chinchilla breeds had the lowest litter size at birth. The effect of breed was gain highly significant for the litter size at weaning. Soviet chinchilla rabbits had the lowest litter size at weaning also. Maximum pre – weaning mortality was seen in the Soviet Chinchilla breed though the effect of the breed was found to be non – significant. The highest litter weight at weaning was seen in grey Giant rabbits and the lowest in the New Zealand White rabbits though the number of rabbits alive in New Zealand White breed were more than in the Soviet Chinchilla rabbits. The mean litter weight at weaning was highest in Soviet Chinchilla rabbits. The overall sex ratio was 52 percent. The estimates of heritability for the litter size at birth and at weaning were negative and hence adjusted to zero.
Inheritance of body weight,egg weight and age at first egg in white leghorn birds
(Department of Animal Breeding and Genetics, College of Veterinary and Animal Sciences, Mannuthy, 1985) Valsala C Joseph; Mukundan, G
An investigation was carried out to study the inheritance of body weights, age at first egg and egg weight in White Leghorn birds. The data required for the study were collected from two strains of White Leghorns maintained in the Farm under All India Co – ordinated Research Project for Eggs, Mannuthy. The Least squares analysis of variance was carried out to find out the effect of hatches on the traits under study. Since the effect of hatch was significant, the data were adjusted for this effect and utilized to estimate heritability, genetic, phenotypic and environmental correlations among body weights and age at first egg. Hatch effect was not significant for egg weight. The averages for body weights (g) at 20 weeks and 40 weeks, age at first egg (days) and egg weight (g) were 1181.5 + 2.8, 1457.0 + 4.0, 166.0 + 0.30 and 51.7 + 0.10 for N strain and 1245.9 + 5.4, 1518.6 + 5.7, 162.1 + 1.1 and 51.7 + 0.10 for P strain respectively. The heritabilities based on sire, dam and sire + dam components of variance were 0.25 + 0.00, 0.36 + 0.01, 0.31 + 0.01, for body weight at 20 weeks; 0.22 + 0.00, 0.50 + 0.03, 0.36 + 0.00 for body weight at 40 weeks; 0.20 + 0.00, 0.22 + 0.03, 0.21 + 0.00 for age at first egg and 0.43 + 0.00, 0.62 + 0.03 and 0.52 + 0.01 for egg weight respectively. In P strain the respective estimates were 0.25 + 0.02, - 0.19 + 0.12 and 0.03 + 0.04 for body weight at 20 weeks; 0.44 + 0.00, 0.27 + 0.04 and 0.35 + 0.02 for body weight at 40 weeks; 0.06 + 0.00, - 0.11 + 0.04 and 0.00 + 0.02 for age at first egg and 0.28 + 0.01, 0.95 + 0.04 and 0.61 + 0.02 for egg weight respectively. The genetic correlations between body weights at 20 weeks and 40 weeks and between body weights and egg weight were positive, between body weights and age at first egg negative and between age at first egg and egg weight positive. Environmental and phenotypic correlations between the traits were generally of low magnitude.
Sasthriyamaya Aaduvalarthal
(Kerala Agricultural University, 1996-07) Mukundan, G