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ThesisItem Open Access 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; KAU; Mukundan, GA study was undertaken to evaluate and compare the chromosomal status of Local non – descript, half – bred Jersey, half – bred Holstein Friesian and Jersey cattle and to assess the incidence of chromosomal aberrations causing physiological disorders. The cattle owned by Kerala Agricultural University. Indo – Swiss Project and farmers formed the material for the study. In all, 102 animals consisting of 71 normal and 31 abnormal, were subjected to the study. Peripheral blood leukocyte culture technique with heparinised whole blood was used for chromosome analysis. The medium was TC 199 with phytohaemagglutinin M as mitotic inducer and colchicine as mitotic arrester. The cells in metaphase were harvested and air dried smears stained with Giemsa. Good spreads were photographed and karyotypes prepared. The efficiency of medium was tested using mitotic drive and mitotic index, which were between 32 to 33 per cent and 5 to 6 per cent respectively. Colchicine treatment of 0.1 ml (0.0001%) for 1 hour yielded clear visible chromosome spreads. The blood samples stored for varying time at 50C indicated that the whole blood transported in ice bath (50 C) is to be used within 12 hours after collection for lymphocyte culture. In normal cattle, diploid chromosome number was found to be 2n = 60 with 29 pairs of autosomes and one pair sex chromosome. The males were heterogametic. All the autosomes were acrocentric in Local, half – bred Jersey, half – bred Friesian and Jersey whereas the x chromosome was biarmed and a large submetacentric in all the genetic groups. The Y chromosome was polymorphic being acrocentric in Local and submetacentric in exotic bulls. No satellite was observed in any of the chromosomes. The relative length of largest and smallest autosomes were 6.5080 and 1.3473 per cent in Local, 6.4735 and 1.2250 per cent in half – bred Jersey, 6.2190 and 1.3788 per cent in half – bred Friesian and 6.9125 and 1.3096 per cent in Jersey respectively. The difference in relative length of autosomes between different genetic groups was not found to be significant. The relative length of x chromosome was 7.2838 per cent, 7.0313 per cent, 6.5138 per cent and 6.3166 per cent in Local, half – bred Jersey, half - bred Friesian and pure Jersey respectively. The differences between genetic groups were significant. In the karyotypic array based on relative length, the x chromosome occupied a first position in Local, half – bred Jersey, half – bred Friesian whereas in Jersey it was in between first and second pair of autosomes. The relative length of Y chromosome was 2.9415 per cent, 2.5745 per cent and 2.9375 per cent in Local, Jersey and Holstein Friesian respectively. The difference Local and Holstein Friesian was not significant. In karyological array the Y chromosome occupied a position between 15th and 16th pair of autosomes in Local and Holstein Friesian whereas in Jersey it was between 15th and 20th pair. The arm ratio of x chromosome was 2.043, 1.986, 1.739 and 1.690 in Local, half – bred Jersey, half – bred Friesian and Jersey respectively. In Local cattle the centromere was located away from mid point compared to other genetic groups. The distance between mid point and centromere was lowest in Jersey. The arm ratio of Y chromosome of Jersey and Holstein Friesian was 1.21 and 1.66 respectively. The location of centromere in Y chromosome of Jersey was more towards centre than that of Holstein Friesian. The centromere index of x chromosome was 0.365, 0.329, 0.338 and 0.372 in Local, half – bred Jersey, half – bred Holstein Friesian and Jersey respectively. The values for the centromere index confirm the findings obtained for arm ratio with regard to the proximity of centromere to the mid point of the chromosome. Among the 31 abnormal cattle, chromosomal aberration were observed in one 4 ½ years old sterile Jersey heifer, one Free martin and one Local bullock with abnormally developed secondary sexual characters. Infertile cattle showing repeat breeding, poor semen quality and poor libido did not exhibit any aberration. In the sterile Jersey heifer, 59/60 mosaicism was observed. The Free martin exhibited 60 XX/60 XY chimaerism having 14 per cent of the cells with XY type and others with XX type. The local bullock revealed abnormal development of teats and secretion of milky fluid. The mitotic spreads were of tetraploid nature (4n = 120) in 4.5 per cent cells and the diploid (2n = 60) in others. This animal was diploid tetraploid chimaera or mixoploid. The present study brought out findings that relative length, position in the karyotypic array, arm ratio and centromere index of sex chromosomes shall serve as tool for identification of inter – breed differences and that the occurrence of tetraploidy stimulate the activity of the female secondary sexual characteristics in male cattle.ThesisItem Open Access 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; KAU; Mukundan, GA 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.ThesisItem Open Access 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; KAU; Mukundan, GRealising 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.ThesisItem Open Access 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; KAU; Mukundan, GBlood 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.