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ThesisItem Open Access MARKER ASSISTED SELECTION FOR MILK PRODUCTION TRAITS IN VECHUR CATTLE(COLLEGE OF VETERINARY AND ANIMAL SCIENCES-MANNUTHY,THRISSUR, 2005) SHYMAJA UTHAMAN; K.V. RaghunandananA study was conducted in Vechur cattle of Kerala to study the association of microsatellite marker alleles with the milk production and composition traits and to evaluate seven ancestors using microsatellite markers. Blood and semen was used as the source of DNA in this study. DNA samples were extracted from fifty unrelated animals and thirty three ancestors and progenies. Five microsatellite markers with established linkage to QTL controlling milk production traits like milk yield, fat percentage and protein percentage were used. The DNA samples obtained from the fifty unrelated Vechur cattle were typed using these five microsatellite markers. The five markers were found to be highly polymorphic with the PIC value ranging from 0.82 at the BM1508 locus to 0.89 at the HUJII77 locus. Data regarding the peak yield, days to attain peak yield, AFC and intercalving period were collected from the Vechur Conservation Centre, Mannuthy. Milk samples collected from the Vechur Conservation Centre were used to determine the milk fat percentage, protein percentage, SNF and total solids. The mean fat percentage and AFC were found to differ significantly in different families. Statistical analysis revealed that the V43 and V88 families had a mean fat percentage significantly greater than the population mean. The mean AFC of V43 family was also found to be significantly greater than the population mean. The V44, V88 and VI17 families had a mean AFC significantly lower than that of population mean. The V44 family had the lowest mean AFC and was also significantly different from the V88 and VI17 families. Microsatellite analysis was carried out for the thirty three combinations of ancestors and progeny using the same five markers. The allelic effect of microsatellite markers in the families was studied for fat percentage and AFC. The allelic mean for fat percentage of 223 bp size allele at the HUJII77 locus was found to be significantly higher when compared to those animals without this allele even though there were no earlier reports indicating linkage between this marker and QTL affecting fat percentage. The allelic mean of fat percentage for 205, 209 and 221 bp at the HUJII77 locus was significantly lower when compared to those of animals without this allele. The mean of the animals with 208 bp allele at the ILSTS096 locus was found to be significantly greater for fat percentage when compared to the mean of those without this allele. There are earlier published reports indicating linkage between this marker and QTL affecting fat percentage. Selection for this allele will not be effective as it is already present in high frequency in the population. The 252 bp allele at the BL41 locus had an allelic mean for fat percentage significantly lower than that for animals without this allele. The 238 bp size allele of this locus had an allelic mean for AFC significantly greater than that for animals without this allele. Earlier reports establish linkage between this marker and QTL affecting fat percentage but not AFC. Selection can be applied against this allele to prevent its frequency from increasing in the population. The allelic mean of 158 bp allele at the BM1508 locus had a mean fat percentage significantly lower than that for the animals without this allele. There are earlier reports of linkage of this marker with QTL affecting protein percentage but not fat percentage. Selection against this allele is necessary as this allele is present in high frequency in the population. Animals with 113 bp allele had an allelic mean of fat percentage significantly lower than that for the animals without this allele. This marker has linkage with QTL affecting milk fat percentage. It is advisable to select against this allele to increase the milk fat percentage in the population. Even though the V44 sire can be selected for improving the fat percentage, the mean AFC of this sire was found to significantly greater than that of the population mean hence it is not preferred. The sire V88 can be selected for improving the fat percentage as well as reducing the AFC. There is a possibility to improve the Vechur cattle maintained at the Vechur Conservation Centre, Marmuthy for fat percentage and AFC by adopting line breeding for V88 sireThesisItem Open Access GENETIC POLYMORPHISM OF MILK PROTEINS IN GOATS(COLLEGE OF VETERINARY AND ANIMAL SCIENCES-MANNUTHY,THRISSUR, 1996) T. V. RAJA; B. NandakumaranThe present investigation was undertaken to identify the biochemical polymorphism at different milk protein loci and to establish their inheritance pattern in Malabari and its exotic cross viz., Alpine x Malabari. It was also envisaged to analyse the association of different milk protein variants with lactation milk yield. Hundred goats belonging to Malabari (50) and Alpine x Malabari (50) were typed for milk protein variants employing horizontal Polyacrylamide Gel Electrophoresis (PAGE). The milk protein loci studied were Alpha Si casein, Alpha Sj casein. Beta casein. Kappa casein and Beta lactoglobulin. Two Alpha Si casein variants, the faster Alpha Si casein F and the slower Alpha Si casein S with three phenotypes Alpha Si casein AA, Alpha Si casein AB, and Alpha Si casein BB were observed. S allele had the frequency of 0.52 in Malabari and 0.70 in Alpine x Malabari crossbreds. The gene frequency of Alpha Si casein F and Alpha Si casein S were 0.48 and 0.52 in Malabari and 0.30 and 0.70 in Alpine x Malabari crossbreds, respectively. The frequency of S allele was higher in both the populations. Alpha Sj casein locus exhibited three phenotypes viz., AA, AB and BB controlled by two alleles A and B. A allele had the ii higher frequency of 0.71 in Alpine x Malabari crossbreds compared to 0.62 in Malabari. Higher frequency of AA phenotype was found in Alpine x Malabari (0.52) and that of AB phenotype in Malabari (0.44) . Two alleles namely A and B contributed three phenotypes viz., AA, AB and BB at the beta casein locus in both the populations studied. Malabari showed higher frequency of B allele (0.55) while Alpine x Malabari had higher frequency of A allele (0.60) . Beta casein AB phenotype had higher frequency in Malabari breed (0.54) . Kappa casein locus showed two alleles A and B contributing three phenotypes viz. , AA, AB and BB. The frequency of A allele was higher in both the population. The phenotype AA was higher in Alpine x Malabari crossbreds (0.56) while Malabari had higher frequency of AB phenotype (0.48) Two alleles namely A and B with three phenotypes AA, AB and BB were identified at Beta lactoglobulin locus. The phenotype AA was dominant in Alpine x Malabari crossbreds (0.50) and the frequency of BB phenotype was almost similar in both Malabari and Alpine x Malabari crossbreds (0.14 in Malabari and 0.12 in Alpine x Malabari crossbreds). The gene frequency of Beta Ig A was found to be 0.65 in Malabari and 0.67 in Alpine x Malabari crossbreds. iii Both the populations studied were in genetic equilibrium with respect to these five milk protein loci. No significant diversity was found to exist between genetic groups. The genetic variability in the populations was calculated by estimating the heterozygosity. The overall heterozygosity in different populations indicated that the Malabari breed had comparatively higher degree of heterozygosity (0.4711) followed by Alpine x Malabari crossbreds (0.4209) . In Malabari maximum heterozygosity was observed at Alpha Si casein loci (0.4992). In Alpine x Malabari maximum heterozygosity was observed at Beta casein locus (0.4800) . The study of association between the genes controlling synthesis of milk proteins showed significant association between the Beta casein with the Beta lactoglobulin BB types in Alpine X Malabari crossbreds. All the other combinations of genes did not show any significant association. Milk protein variants were not found to be associated with the lactational yield (120 days) of the goats. The present study could establish the existence of biochemical polymorphism at Alpha Si casein, Alpha Sj casein, Beta casein. Kappa casein and Beta lactoglobulin loci in Malabari and Alpine x Malabari crossbreds studied.ThesisItem Open Access SERUM ALKALINE PHOSPHATASE POLYMORPHISM IN CROSSBRED CATTLE OF KERALA(COLLEGE OF VETERINARY AND ANIMAL SCIENCES-MANNUTHY,THRISSUR, 1995) JACOB ABRAHAM; B. NANDAKUMARANThe present investigation was undertaken to identify the the biochemical polymorphism at serum alkaline phospha- tase (SAP) loci and to study the heterogenity of SAP variation in crossbred cattle. It was also envisaged to analyse the association of SAP variation and traits of economic importance such as milk production and composition of milk. One hundred and ten animals belonging to two different crosses of local nondescript cattle viz. Crossbred Holstein Friesian (57) and Crossbred Brown Swiss (53) were typed for SAP variance by standardising Horizontal Polyacrylamide Gel Electrophoresis (PAGE). Two genotypes FS and SS were determined. The highest frequency of FS genotype was in Holstein Friesian crossbred than in Brown Swiss crossbred. The genotype FF was absent in both the crossbreds. The highest frequency of SS genotype was in Brown Swiss crossbred than in Holstein Friesian crossbreds. Two alleles namely pF and pS with two phenotypes FS and SS were identified as SAP locus. pT allele had the frequency of 0.20 and pS allele had the frequency of 0.80 in the pooled crossbreds. Both the Holstein Friesian crossbreds and Brown Swiss crossbred are in genetic equilibrium at the SAP loci. No association could be established between milk yield (305 days) and serum alkaline phosphatase level. A non significant negative correlation existed between milk fat percentage and SAP level whereas a significant positive correlation existed between milk SNF percentage and SAP level. The correlation between SAP level and milk total solids were found to be negative and non significant in Brown Swiss 1 I i / crossbreds whereas a non significant positive correlation existed between the SAP level and milk total solids in Holstein Friesian crossbreds. Animals belonging to the FS genotype are better milk producers compared to the SS genotype. For higher fat percentages, the performance of SS genotype was compara- tively better. The performance of SS genotype Ls better for producing milk with more than 8.5 percentage of SNF. FS genotype performed better for producing milk having higher percentage of total solids.ThesisItem Open Access GROWTH AND SURVIVABILITY OF GH/Msp I GENOTYPES IN MALABARI GOATS(College of Veterinary and Animal Sciences, Mannuthy., 2004) BINDU MATHEW; Dr. k.C. RaghavanGrowth hormone gene, due to its essential role in lactation and growth processes, is a perfect candidate marker associated with somatotropic axis. Selection of animals based on the growth hormone genotypes can be tntroduced in the animal husbandry sector for better production. The present investigation was undertaken to study the growth and survivability of GH/Mspl genotypes in Malabari goats at different centers of Badagara. Thalassery. Thanur as well as Malabari conservation unit. Regional Agricultural Research Station, Pilicode. DNA was isolated from 32 bucks, 241 does mated to those bucks and 297 of their progeny using phenol - chloroform extraction method. A 768-bp fragment from third exon to fifth exon containing the polymorphic Mspl site was amplified well using bovine primers, indicating species homology. The amplified product on digestion with the Mspl enzyme revealed the GWMspl {+) and (-) alleles. The percentage of incidence of (+/-) genotype was 61.76 and that of (+/+) genotype was 38.24. None of the animals typed were of the GH/Mspl (-/-) genotype. The genotype frequencies of bucks and does were consistent with the general population. In the specific heterozygous mating (+/- x +/-), 28 per cent of the progenies were (+/+) homozygotes and the rest 72 per cent were heterozygotes (+/-). Early embryonic mortality was not found to be a cause for the absence of the GH/Mspl -/- genotype as the kidding percentage in heterozygous mating were not different from other types of ma.rngs. There was no relationship between growth upto SIX months of age and G\l!Msp\ genotypes. The study conf.mrs a strong heterozygotie advantage for the GH/Mspl +/genotype and also the absenee of GH/Mspl -/- genotype in Malaban goats. Presence of duplicate copies of the growth hormone gene in goats may be a possible reason for the above results.ThesisItem Open Access MICROSATELLITE MARKER BASED CHARACTERIZATION OF INDIGENOUS PIGS OF KERALA(College of Veterinary and Animal Sciences, Mannuthy., 2006) ARIPRASATH. K; Dr. A.P. UshaThe study was undertaken to assess the genetic diversity among four indigenous pig population of Kerala using microsatellite markers. The animals were selected from various part of Kerala, population I included the conserved Angamali pigs from university farm, Mannuthy, population II consisted of animals from Koothattukualm, population III were the animals from Ollur and animals from border districts of Kerala formed the population IV. Genetic analysis was carried out using five polymorphic microsatellite markers. Blood samples were collected from 100 unrelated indigenous pigs from all four populations and DNA was isolated. The phenol-chloroform method of extraction yielded 224.35±9.86pg/5ml of blood. PGR conditions were standardized for all five selected markers namely, S0005, SOlOl, SW1026, SW2517 and S0008. The forward primer of each marker was endlabelled with 732 P-ATP as source of radio signal. The Ml3 single strand DNA was sequenced and used as a size standard. Autoradiography was employed to visualize the results. A total of eight alleles were detected in S0005 and SOlOl, five alleles in each of SW1026 and S0008, and six in SW2517. The heterozygosity varied from 0.7747 in SW2517 to as large as 0.8475 for S0005. The heterozygosity values for SOIOI, SW1026 and S0008 were 0.7774, 0.7672, and 0.7424 respectively. The PIC values ranges from 0.6974 for S0008 to 0.8291 for S0005. The PIC values for SOIOI, SW1026 and SW2517 were 0.7483, 0.7284 and 0.7381 respectively. The allele frequencies were used to estimate the Nei's standard genetic distance among the populations. The distance measure ranged from 0.5704 to 0.7161, with the highest value noticed between population II and IV and the lowest between population I and III. A dendrogram was constructed using the POPGENE version 3.2 program which grouped the population I and IV in one cluster and II and III populations in another cluster. >ThesisItem Open Access MILK PROTEIN POLYMORPHISM AND MILK COMPOSITION IN VECHUR CATTLE(COLLEGE OF VETERINARY AND ANIMAL SCIENCES Mannuthy - Thrissur, 1996) THIRUPATHY VENKATACHALAPATHY, R.; SOSAMMA IYPE; THIRUPATHY VENKATACHALAPATHY, R.The native cattle of Kerala have been evolved through several generations of natural selection against high humidity, heavy rainfall and hot climate. They have been considered as non-descrlpt animals, but there has been variety with characters distinguishing from others and known as Vechur cattle of Kerala. The Vechur cattle had their origin In Vechur near Valkom of Kottayam district of Kerala. They were very popular four decades back for their relatively higher milk production compared to other, local cows. The extremely small size of the cow, . good adaptation and high disease resistance are the traits very much favoured by the farmers. Farmers prefered Vechur cattle for ploughing In marshy lands because of the small size and light weight. The emergence of crossbreeding led to the gradual reduction In tradatlonally reared Vechur cattle. Under this circumstances, the present work was undertaken to characterise the Vechur cattle of Kerala by studying (a) certain genetic markers In milk (b) milk components like fat, total solids and solids not fat percentage (c) fat globule size and distribution and (d) Iodine value. The Vechur cows maintained under the scheme on "Conservation of germplasm of Vechur cattle" formed the material for the study. Milk proteins such as casein and whey proteins were studied by polyacrylamide gel electrophoresis in horizontal dimension (Thompson and Kiddy, 1963). The fat, total solids, solids not fat percentage of milk and iodine value of milk fat were estimated as prescribed by Indian Institution Standards. The fat globule size was measured under microscope by fitting an eye piece micrometer to the eye piece of the microscope. The statistical analysis were done as suggested by Snedecor and Cochran (1967). The influence of stage and time of milking were worked out using least squares analysis of variance as described by Harvey (19 86) . Three proteins a, f3 and k-casein were identified in casein system. At a^^-casein locus three phenotypes viz. BB, BC and CC determined by two allele B and C were observed. Frequency of CC phenotype (0.64) was highest ^ followed by BC (0.22) and BB (0.14). Frequency of B and C allele were 0.25 and 0.75. The /3-casein locus consisted three phenotypes viz. AA, AB and BB with A and B allele. The frequency of AB phenotype was highest (0.57) followed by AA (0.29) and BB (0.14). Frequency of ^ arlele was 0.5/. At k-casein locus two phenotypes AA and AB with A and B allele were identified. The frequency of AB was (0.83) and frequency of A allele was 0.59. Two whey proteins a-lactalbumin and /3- lactoglobulin were identified. At a-lactalbumin locus two phenotypes AA and AB with two allele A and B were observed. The frequency of AA and AB phenotypes were 0.57 and 0.43. The frequency of A and B allele were 0.78 and 0.22 respectively. The /3-lactoglobulin locus consisted of three phenotypes viz. AA, AB and BB with A and B allele with frequency of 0.57, 0.29 and 0.14 respectively were identified. The frequency of A allele was 0.71. The frequency of C allele at a^^-casein locus was lower than the other Indian breeds like Sahiwal, Tharparkar, Red sindhi and Rathi, but higher than exotic breeds like Jersey and Holstein and crossbred cattle of Kerala. The A variant at f3 and k-casein locus had frequency lower to other Indian breeds, exotic breeds of cattle and crossbred cattle of Kerala. The A variant at c*-lactalbumin and /3-lactoglobulin locus had much higher frequency than other Indian, exotic breeds of cattle of cattle and crossbred cattle of Kerala. B variant in Vechur cattle was lower in frequency compared to other Indian breeds. The average milk fat percentage for 1-44 weeks of lactation was 5.95 +0.12, 6.62 ± 0.13 in the morning and evening respectively and the mean milk fat percentage for morning and evening milk was 6.23 + 0.19. The mean milk fat percentage at first week was 4.05 ± 0.19, 4.65 + 0.17 and by 20 th week of lactation was 5.92 + 0.08, 6.55 ± 0.07 in the morning and evening milk respectively. The evening milk had uniformly higher fat percentage than morning milk. The fat percentage showed an increasing trend with advancing stage of lactation. The least squares means for morning and evening milk were 5.99 + 0.03 and 6.62 ± 0.03 respectively and overall mean was 6.13 ± 0.04. The mean total solids percentage of milk at first week was 12.64 ± 0.17 and 13.57 ± 0.19 in the morning and evening milk and it steadily increased to 14.75 ± 0.13 and 15.31 + 0.18 in the morning and evening milk by 20 th week of lactation. The average total solids percentage in milk from 1 -44 weeks of lactation was 14.79 ± 0.13 and 15.53 + 0.13 in the morning and evening respectively and the average for morning and evening together was 15.16 i 0.11 per cent. An increasing trend was noticed in total solids percentage as the lactation advanced. The evening milk showed uniformly higher total solids percentage compared to morning. The least squares mean was 15.02 and the adjusted mean for morning and evening was 14.85 ± 0.05 and 15.55 ± 0.05 per cent. Least squares analysis of variance showed a significant effect of time of milking and stage of lactation on milk fat and total solids percentage of milk. The average solids not fat percentage from 1 - 44 weeks of lactation was 8.84 ± 0.12 and 8.92 ± 0.14 in the morning and evening milk respectively. The average for morning and evening milk was 8.88 + 0.13 and least squares mean was 8.90. The mean solids not fat percentage of milk at first week was 8.60 + 0.24 and 8.93 ± 0.22. It was 8.83 ± 0.11 and 8.76 ± 0.15 percent at 20 th week of lactation in the morning and evening milk respectively. No trend of increase was noticed in the solids not fat percentage in relation to the stage of lactation. The least squares analysis of variance showed no significant effect of time of miling and stage of lactation on solids not fat percentage. Total solids and solids not fat did not have strong association in general. The positive correlation between total solids and fat percentage were not significant. The negative correlation between fat and solids not fat percentage were also not significant. The milk fat and total solids percentage were higher than other Indian breeds of cattle, but lower to buffalo. The solids not fat percentage of milk was similar to other Indian br-eeds of cattle. The mean size of fat globule was 3.21 and the range was 2.54 to 4.07 /.i. The mean diameter of fat globules was found to be 3 .02 + 0.05 jj, in the morning and 3.40 + 0.05 in the evening milk. The mean size of fatf globules ^timated in goat (Malabari and their crosses), crossbred cattle and Murrah buffalo were 2.60 u., 4.87 jj, and 5.81 /./ respectively. The average fat globule size was found to be decreasing as the lactation advanced. The proportion of small size fat globules were found to be increased and the larger size of fat globules decreased towards the end of lactation. No correlation was noticed between fat globules size and fat percentage. The iodine value ranged from 28.61 to 30.29 and the average iodine value was 29.60 ± 2.20. Based on available reports this appeared to be similar to buffalo, higher than goat and lower than cows. The size of fat globule (3.21 u.) was higher than the goat and lower to the other breeds of cattle and buffalo. since the milk fat has higher proportion of smaller size fat globules and saturated fatty acids, it would be therapeutically useful in malabsorption syndromes due to its easy digestability. The larger proportion of small size fat globule is associated with high phospholipid content because of greater surface area. Phospholipids are important in the development of nervous system in babies. Thus Vechur cow milk appear to be suitable for infants and even sick. Studies on more number of cows are required for confirmation of results. It can be concluded that Vechur cattle of Kerala has unique characteristics of its own and have separate identity from other breeds of cattle not only by its small size but also due to its milk protein variants, composition of milk, size of fat globules and level of saturated fatty acids.ThesisItem Open Access GENETIC DIVERSITY ANALYSIS OF GOAT BREEDS USING MICROSATELLITE MARKERS(College of Veterinary and Animal Sciences, Mannuthy., 2005) AMRITA SUSAN JACOB; Dr. T.V. AravindakshanThe study was undertaken to assess the genetic vana^lfly' tSnong four goat breeds of South India using microsatellite markers. Three breeds studied were native to Kerala. These were Malabari, Attappadi Black and non-descript goats of Thrissur. The fourth breed, Salem Black, originated in the Salem district of Tamil Nadu. Microsatellite analysis was carried out using four highly polymorphic bovine markers. Blood samples from 30 genetically unrelated animals of each breed were collected and used as a source of DNA. The phenol-chloroform extraction procedure was used and the mean yield of DNA obtained was 361.43±10.73 pg/five ml blood. The four markers selected for the study were, INRA63, ILSTS030, HUJII77 and BM6121. PGR conditions were standardised for all the primers. The forward primer of each primer pair used in the PGR assay was end labeled with y^^P-ATP prior to setting up of the PGR. Ml 3 DNA was sequenced and used as the size standard. The PGR products were separated by denaturing polyacrylamide gel electrophoresis. Detection of the products was done by autoradiography. Gels after electrophoresis were dried and was set for autoradiography with X-ray film in a cassette fitted with intensifying screen. Allele sizes were obtained by comparing with the sequence of Ml 3 single stranded DNA size standard. A total of eleven alleles were detected at the INRA63 locus. The mean heterozygosity and PIG values obtained were 0.774 and 0.743, respectively. Seventeen alleles were detected at the ILSTS30 locus. The mean values of heterozygosity and PIG were 0.878 and 0.866, respectively. Thirteen alleles were detected at the BM6121 locus with mean heterozygosity and PIG values of 0.851 and 0.833, respectively. The HUJII77 locus was the most polymorphic of all the four loci detecting 21 alleles. The mean heterozygosity and PIG values were 0.899 and 0.88, respectively. The allele frequency measures were used to estimate the Nei's standard genetic distance among the populations using the POPGENE program. The distance measures ranged from 0.388 to 0.224, with the highest value noticed between Salem Black and non-descript goats of Thrissur and the lowest between Malabari and non-descript animals. A dendrogram was constructed using the POPGENE program which grouped the Salem Black and Attappadi Black goats in one cluster and Malabari and the non-descript goats of Thrissur in another.ThesisItem Open Access COMPARATIVE EVALUATION OF LITTER TRAITS IN DESI, LARGE WHITE YORKSHIRE AND THEIR CROSSBRED PIGS(COLLEGE OF VETERINARY AND ANIMAL SCIENCES-MANNUTHY,THRISSUR, 2001) GOPINATHAN., A.; USHA, A. P.The present study was undertaken to compare and evaluate litter traits in Large White Yorkshire, Desi and their Crossbred pigs and to decide a breeding strategy. The data on 20-25 farrowings were collected from Centre for Pig Production and Research, Mannuthy for Large White Yorkshire, Desi and Crossbred pigs. A random sample of eight animals from each genetic group was selected and maintained from weaning to eight month of age to study the growth, feed conversion efficiency and carcass characteristics. The average birth weight and weaning weight, litter size at birth and weaning, litter weight at birth and weaning, pre-weaning mortality for each genetic group were calculated. Large White Yorkshire was found to be superior for all traits followed by Crossbred and Desi pigs. Crossbred pigs had lowest pre-weaning mortality while Desi pigs had highest litter size at birth. Analysis of variance showed that the effect of genetic group was found to be highly significant for all litter trmts except litter size at birth and weaning. The data were analysed using least squares analysis of variance to study the effect of different factors on birth weight and weaning weight in all three genetic groups. Least squares analysis of variance for birth weight revealed that the effect of sire and litter size at birth was highly significant in all three genetic groups. Sex had significant effect only in crossbreds. For weaning weight, the effect of sire and litter size at birth were found to be highly significant while sex did not show a significant effect on weaning weight in all three genetic groups. The effect of genetic group was found to be highly significant for third, fifth and eighth month body weight. But there was no significant effect noticed between Large White Yorkshire and Crossbred pigs during third month. The average daily gain and feed conversion efficiency was highest for Large White Yorkshire followed by Crossbred and Desi pigs from weaning to eight months of age. In carcass traits like back fat thickness, loin eye area, dressing percentage and carcass length. Large White Yorkshire averaged better than Desi and Crossbred pigs. The effect of genetic group was found to be highly significant for all carcass traits. The cost of production per kg of live body weight was calculated in three genetic groups, Large White Yorkshire had lower cost of production when compared to Crossbred and Desi pigs from weaning to eight month of age. The present study revealed that Large White Yorkshire had higher body weight gain, better feed conversion efficiency, average daily gain and higher values for carcass and litter traits when compared to Crossbreds and Desi pigs.ThesisItem Open Access POLYMORPHISM OF GROWTH HORMONE GENE IN MALABARI GOATS {Capra hircus)(COLLEGE OF VETERINARY AND ANIMAL SCIENCES-MANNUTHY,THRISSUR, 2002) CHITRA, R.; Aravindakshan, T.V.Malaban goats are noted for their high milk yield and meat production qualities. They represent a unique genetic resource by virtue of their adaptability, resistance to many infectious diseases and prolificacy in the humid tropics of Kerala. They also exhibit considerable variation in individual performance m milk production, growth rate and fecundity. The growth hormone (GH) gene is a potential target for studies of molecular variation because of its possible direct or indirect effects upon growth, lactation and mammar>' gland development in dair>' animals. The polymorphism m the third mtron of GH gene was investigated by polymerase chain reaction (PGR) and restriction endonuclease digestion. Genomic DNA was isolated from a random sample of 196 genetically unrelated Malaban does in second lactation belonging to three different population groups based on geographical locations. The mean yields of DNA from 5 ml of whole blood extracted by phenol-chloroform was 231.097±11.65 pu. The ratio of optical densities at 260 and 280 nm was above 1.7 indicating good deprotemisation. Oligonucleotide primers based on bovine sequences were used for amplification of GH gene in goats. The successful amplification of the expected 768 bp fragment indicated the suitability of bovine primers for goats and conservation of DNA sequence in related species. The digestion of the amplified product with Msp\ restriction enzyme revealed two alleles viz., Msp\ (+) and Msp\ (-) with gene frequencies of 0.70 and 0.30, respectively. In the Malabari goats tested in this study only (+/+) and (+/-) GH/Mspl genotypes were encountered where as none of the animal was of the (-/-) genotype. It is suspected that the Msp\ (-) allele in the homozygous condition might be lethal or linked to a lethal gene. The population of the Malabari goats investigated in the present study was not under Hardy-Weinberg equilibrium though it was a large random mating one with no known mutation, or migration. Hence, it is suspected that the selection process acting against the (-/-) genotype through reduced viability or early embryonic death may be a possible reason for the disagreement of the Hardy-Weinberg equilibrium in Malabari goats for this locus. It was observed that the goat population was in genetic equilibrium with respect to growth hormone locus in all population groups. The genetic equilibrium might be indicative of the homogeneity of different population groups though they differed significantly with respect to morphological and other phenotypic characters. Studies on the association of GH/Mspl genotypes with growth and milk traits in Malabari goats revealed the following results. The (+/-) genotype was superior to (+/+) genotype with respect to milk protein percentage in population-1. The (+/-) genotype was found to be associated with significantly high milk SNF percentage in population II and pooled population. The GHIMspl genotypes did not exhibit significant effect on body weight, body measurements, peak milk yield, milk fat and the litter size. The , ^ T. Kil-I ARY ) population groups differed significantly with respect to body weight, body measurements like length, heart girth and height at withers, peak milk yield and litter size. These results revealed the influence of management and other environmental effects on growth traits in Malabari goats. It is concluded that the typing of the Msp\ polymorphism using PCR-based procedure is a very efficient way to identify the GH genotypes in Malabari goats