PG Thesis

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    Genetic divergence in rabbits used for breeding in Kerala
    (Department of Animal Breeding and Genetics, College of Veterinary and Animal Sciences, Mannuthy, 2007) NIsha Valsan; Bindhu, K A
    The genetic divergence among three breeds of rabbit, viz. Newzealand White, Soviet Chinchilla and Grey Giant was studied using microsatellite markers. A set of twelve microsatellite markers were tested, out of which three markers (Sol 03, Sol 33 and Sol 44) were selected based on their polymorphism. The PCR products were separated by denaturing polyacrylamide gel electrophoresis and autoradiographed. The Sol 03 locus was found to be the most polymorphic with fourteen alleles in the pooled population. The values for heterozygosity and PIC in Newzealand White at the Sol 03 locus were recorded as 0.840 and 0.836, in Soviet Chinchilla as 0.766 and 0.764, while in Grey Giant, the heterozygosity and PIC values stood at 0.775 and 0.765, respectively. Eight alleles were detected at the Sol 33 locus. The maximum values for heterozygosity (0.858) and PIC (0.854) were observed in Grey Giant while Newzealand White (0.672 and 0.667, respectively) recorded the lowest. In Soviet Chinchilla, values for heterozygosity and PIC were 0.691 and 0.680 respectively. with mean heterozygosity and PIC values of 0.740 and 0.764. Sol 44 locus revealed four alleles. The highest values for heterozygosity (0.728) and PIC (0.702) at the Sol 44 locus were recorded in Grey Giant, while the lowest (0.567 and 0.477) in Soviet Chinchilla. The heterozygosity and PIC values were 0.586 and 0.502, respectively in Newzealand White. The genetic distance was calculated based on Nei’s formula, and the highest value was noticed between Soviet Chinchilla and Grey Giant (0.6942) while the lowest between Newzealand White and Soviet Chinchilla (0.2022). The dendrogram constructed using POPGENE program grouped Newzealand White and Soviet Chinchilla in one cluster indicating their closer relationship. Grey Giant was found to be the most widely separated breed.
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    Genetic and phenotypic variations of geographically different goat populations of Kerala
    (Department of Animal Breeding and Genetics, College of Veterinary and Animal Sciences, Mannuthy, 2007) Jimcy Joseph; Raghavan, K C
    Genetic diversity of four geographically different goat populations in Trivandrum, Kottayam, Thrissur and Kozhikode districts in Kerala was analysed based on physical, biometrical traits and microsatellite markers. Based on physical traits, the populations were not very distinct and uniformity was seen with respect to coat colour, horn pattern, presence or absence of tassels or beard and hair pattern. The animals were predominantly horned and short haired with coat colour of white or a combination of white with either black or brown. Majority of animals did not possess tassels or beard. The biometrical traits observed in the present study were body measurements, peak yield and prolificacy. Body weight of adult female goats was predicted using the regression equation based on the power function of chest girth. It was shown that the animals of Trivandrum district had higher values for almost all body measurements and predicted body weight, while the Thrissur population had lowest values for these growth traits. Animals of Kottayam and Kozhikode came in between. Percentage of multiple births was also higher in Trivandrum goat population (68) compared to other populations indicating high prolificacy. Highest peak yield was recorded for Kottayam goat population. Discriminant analysis based on morphometric measurements revealed that the most discriminative variables were head width and body length, followed by shin circumference and rump length. Mahalanobis distance calculated based on morphometric traits indicated that Thrissur and Trivandrum populations were more distant, while least distance was observed between Kottayam and Kozhikode. Discriminant analysis based on body weight, peak yield and prolificacy revealed that only body weight and peak yield variables have significant discriminative capacity. Trivandrum, Kottayam and Kozhikode populations were grouped together in one cluster based on the distance value. Thrissur population was distant from all other populations. Microsatellite analysis revealed that all the five loci were highly polymorphic with five to nineteen alleles in different populations. The total number of alleles, the mean number of alleles per locus, mean heterozygosity and mean polymorphic information content were 51, 10.2, 0.8201 and 0.8104, respectively. The values indicate that the markers can be successfully used to study the variations existing in the populations. Based on Nei’s genetic distance Thrissur and Trivandrum population were grouped together first and then with Kozhikode population, while the Kottayam population formed a unique branch in dendrogram. Unrelated distance values produced by quantitative and molecular measures of variation may be attributed in part to the environmental influences and local selection pressures. Though use of more number of markers may possibly explain the variation encountered in these traits, the present investigation reveals that selection within each population for traits of economic importance like body weight and milk production is the best method to improve the performance of goats of Kerala.
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    Microsatallite marker based characterization of indigenous pigs of Kerala
    (Department of Animal Breeding and Genetics, College of Veterinary and Animal Sciences, Mannuthy, 2006) Ariprasath, K; Usha, A P
    The 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±9.86µg/5ml of blood. PCR conditions were standardized for all five selected markers namely, S0005, S0101, SW1026, SW2517 and S0008. The forward primer of each marker was endlabelled with γ32 P-ATP as source of radio signal. The M13 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 S0101, 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 S0101, 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 S0101, 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.
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    Evaluation of porcine immune responses among different genetic groups
    (Department of Animal Breeding and Genetics, College of Veterinary and Animal Sciences, Mannuthy, 2005) Jeeeba K George; Rajan, M R
    Porcine immune responses were evaluated using PHA skin test and microhaemolytic assay in this study. Investigation was undertaken in three genetic groups namely Desi, Large White Yorkshire and Duroc x Large White Yorkshire. The economic traits studied were birth weight, litter size at birth, weaning litter size and weaning body weight. The cell-mediated immune response was assessed by noting cutaneous response to intradermal injection of phytohaemagglutinin. Humoral immune response was assessed by noting antibody response to sheep red blood cells. Correlation of immune response with growth, disease occurrence and mortality among the littermates were also evaluated. The highest birth weight, body weight at weaning, litter size at birth and weaning were recorded in Duroc x Large White Yorkshire, medium in Large White Yorkshire and least in Desi. The increase in skin thickness at 24, 48 and 72 hour post- injection of PHA-M was highest in Desi, medium in Duroc x Large White Yorkshire and least in Large White Yorkshire. The correlations of cutaneous response to phytohaemagglutinin with pre- weaning mortality among littermates and enteritis were found to be non-significant in Desi, Large White Yorkshire and Duroc x Large White Yorkshire piglets. Among three genetic groups, serum samples from Desi piglets had a higher mean antibody titre on 7th, 14th, 21st day than the other two. Medium titre was noted in Duroc x Large White Yorkshire and least in Large White Yorkshire. Sire effect was highly significant with antibody response on seventh, fourteenth and 21st day post inoculation. The correlations of antibody response to sheep RBC with pre- weaning mortality among littermates and enteritis were also found to be non-significant in Desi, Large White Yorkshire and Duroc x Large White Yorkshire piglets. The effects of sires within Desi, Large White Yorkshire and Duroc x Large White Yorkshire were found to be highly significant (P<0.01) on antibody response to sheep RBC on 7th, 14th and 21st day. Different litter traits had no significant effect on cutaneous response to PHA-M and antibody response to sheep RBC. High heritabilities were estimated for pre-injection skin thickness, cutaneous response to PHA-M at 24, 48, 72 hour post-injection and antibody response to sheep red blood cells on 7th, 14th, 21st day post- inoculation. Correlations of antibody response to sheep RBC on 14th day with cutaneous response to phytohaemagglutinin at 24 hour and 48 hour were found to be non-significant. Antibody response to sheep RBC on 21st day correlated non-significantly with cutaneous response to PHA-M at 24 hour and 48 hour. Antibody response to sheep RBC on 7th, 14th and 21st day associated non-significantly with weaning body weight and pre-weaning mortality. Even though correlations were non-significant, they revealed a negative trend. The association between cutaneous response to PHA-M at 24 hour and birth weight was non-significant.
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    Genetic diversity analysis of goat breeds using microsatellite markers
    (Department of Animal Breeding and Genetics, College of Veterinary and Animal Sciences, Mannuthy, 2005) Amrita Susan Jacob; Aravindakshan, T V
    The study was undertaken to assess the genetic variability among 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 µg/five ml blood. The four markers selected for the study were, INRA63, ILSTS030, HUJII77 and BM6121. PCR conditions were standardised for all the primers. The forward primer of each primer pair used in the PCR assay was end labeled with γ32P-ATP prior to setting up of the PCR. M13 DNA was sequenced and used as the size standard. The PCR 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 M13 single stranded DNA size standard. A total of eleven alleles were detected at the INRA63 locus. The mean heterozygosity and PIC values obtained were 0.774 and 0.743, respectively. Seventeen alleles were detected at the ILSTS30 locus. The mean values of heterozygosity and PIC were 0.878 and 0.866, respectively. Thirteen alleles were detected at the BM6121 locus with mean heterozygosity and PIC 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 PIC 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 PHYLIP package. 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.
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    Body weight and its association with age at first calving and milk production in crossbred cattle of Kerala
    (Department of Animal Breeding and Genetics, College of Veterinary and Animal Sciences, Mannuthy, 2000) Siddalingswamy Hiremath; Stephen Mathew
    The present study was undertaken with a VIew of estimating body weights of crossbred calves in the field conditions of Kerala at birth, three, six and twelve months of age and to find association of these body weights with age at first calving and first lactation milk yield. The data for the present study were taken from the records of ICAR Field Progeny Testing Scheme of Centre for Advanced Studies in Animal Genetics and Breeding, Kerala Agricultural University. The data were of the 1993-2000 period. Body weights at birth, 3, 6, 12 months and at calving were predicted from body measurements using Minnesota formula given by J ohnson,( 1940). The data were analyzed using least squares analysis of variance to study the effects of non-genetic factors on different traits under study. The data adjusted for significant non-genetic factors .. were used to study the effect of sire and for estimating heritability and correlation among body weights and between body weights and age at first calving and between body weights and first lactation milk yield. The overall average body weights of crossbred calves at birth, 3,6 and 12 months of age were 26.0 ± 0.38 kg, 48.7 ± 1.26 kg, 74.1 ± 2.81 kg and 151.0 ± 7.74 kg, respectively. Least squares analysis of variance has shown that the effect of season of birth was significant (P~0.05) only on body weight at six months of age. The influence of period of birth was significant for all body weights upto one year age except for body weight at six months of age. Centre was a significant source of variation for all body weights upto one year age, The mean Age at First Insemination, Age at first calving and Weight at first calving of crossbred cattle were 689.3 ± 22.9 days, 1013.6 ± 21.74 days and 284.9 ± 7.71 kg respectively. The season of birth did not affect age at first insemination, age at first calving and weight at first calving. The significant (P~0.05) influence of period of birth and centre were 11 observed on age at first insemination and age at first calving only but not on weight at first calving. The effect of period of calving and centre on first lactation milk yield was significant whereas the effect of season of calving and age at first calving did not affect first lactation milk yield. The average first lactation milk yield of crossbred cows was 1958.5 ± 30.74 litres. The sire wise means of body weight at six months of age, weight at first calving and first lactation milk yield did not differ significantly but sire effect was significant (P~0.05) in all the other traits. Heritability estimates were calculated by paternal half sib method for different traits under study. The low heritability estimate was obtained for birth weight, body weight at six months of age, age at first calving and weight at first calving. But the heritability estimates of body weight at three months of age and body weight at twelve months of age were high. Age at first insemination was moderately heritable. The heritability estimate of first lactation milk yield was -0.069 ± 0.05. iii Association among body weights and that between body weights and age at first calving followed no definite trend. However, the genetic correlation (0.46) between body weight at six months and first lactation milk yield and high, positive (> 1) genetic correlation between body weight at twelve months and first lactation milk yield indicates strong genetic association of body weight at six months and body weight at twelve months with first lactation milk yield and their relationship can be used advantageously for selection of heifers for milk production under field conditions
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    Comparative evaluation of litter traits in desi, large white yorkshire and their crossbred pigs
    (Department of Animal Breeding and Genetics, College of Veterinary and Animal Sciences, Mannuthy, 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 traits 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
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    Genetic factors influencing feed efficiency in pure and crossbred broiler rabbits
    (Department of Animal Breeding and Genetics, College of Veterinary and Animal Sciences, Mannuthy, 2000) Kasiviswanathan, D; Raghavan, K C
    An experiment was carried out to study the genetic and non- genetic factors influencing feed efficiency (feed g/gain g) in broiler rabbits viz. New Zealand White (NZW), Soviet Chinchilla (SC) and SC x NZW crossbreds (CB). The non-genetic factors induded were sex, litter size at birth, season and year of birth. The data pertaining to fortnightly body weight from four to 12 weeks of age, feed efficiency (FE) and daily gain (OG) were subjected to least squares analysis. Breed had significant effect on body weights at all ages. NZW had the least body weights through out the experiment and SC and CB did not differ significantly at market age of 12 weeks. Overall daily gain was not affected by breed while FE was significantly (P.:: 0.01) influenced by breed. CB had the highest FE followed by SC and NZW rabbits. Dressing percentage was highest (48.91) for CB compared to NZW and SC. Crossbred rabbits exhibited a heterosis of 1.6 and 9.3 per cent for iz" week body weight and FE respectively over the pure bred parents. Sex was not a source of variation for any trait except for body weight at weaning (four weeks). Litter size at birth had significant effect on body weights at all ages but had no effect on overall OG and FE. Season and year of birth influenced body weights at early ages only and had no effect on overall OG and FE. Estimates of heritability by sire + dam component of variance were moderate to high for body weights at different ages, high for DG and not different from zero for FE. Phenotypic correlations among body weights at different ages were high and significant and genetic correlation estimates were higher in magnitude for later ages. Phenotypic and genetic correlation of FE with twelfth week body weight and DG were near to zero. The present study indicated that breed is a significant source of variation affecting body weight from four to 12 weeks of age and FE in during period. CB rabbits though did not differ from SC for 1 z" week body weight excelled the pure breeds when FE and dressing percentage are considered. In monetary terms CB rabbits are found to be superior by 1.6 and 1.43 times over NZW and SC rabbits. So, crossbreeding of SC and NZW rabbits is advocated for profitable commercial broiler rabbit production.
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    Serum immunoglobulin level in kids and its association with growth and mortality
    (Department of Animal Breeding and Genetics, College of Veterinary and Animal Sciences, Mannuthy, 1981) Nandakumar, P; Rajagopala Raja, C A
    Various aspects of transfer of passive immunity from the dam to the kid and its probable associations with various parameters as genetic group type of birth, birth weight, survivability and growth were studied. The sera of neonatal male kids were subjected to Zinc Sulphate turbidity test and the optical density values were converted into Ig concentration (mg/ml) using the prediction equation prepared from known strengths of commercial bovine gammaglobulins. Pre – colostral Ig levels were estimated in five kids. They were then bled at bihourly intervals to locate the post colostral peak. The trend in post colostral serum Ig level and the effect of periods and individuals on it were analysed. Magnitude of peak Ig level was estimated in 51 kids. The trend in serum Ig levels was estimated in ten kids on alternate days during the first week and weekly once thereafter upto eight weeks. The variation due to individuals and periods were analysed. The effect of genetic group on the post colostral peak of serum Ig level were analysed in 20 Saanen x Malabari (SM) 13 Saanen x Saanen – Malabari (SSM) and 12 Sannen x Alpine – Malabari (SAM) kids. The effect of type of birth on post colostral peak level of serum Ig in 12 single kids, 31 twins and 8 triplets were studied. The correlation between birth weight and post colostral peak of serum Ig in 51 kids was estimated. The mean post colostral peak level of serum Ig in kids died within two months was compared to that of population. The percentages of mortality in kids with above and below 70 mg/ml of serum Ig were calculated separately. The correlation between post colostral peak level of serum Ig and weight gain at 56 days was also calculated. The correlation between weekly trend in serum Ig level and the corresponding body weights was calculated. The pre – colostral Ig level ranged between zero and 0.94 mg/ml with a mean of 0.4156 mg/ml. The Ig level rose rapidly in sera and reached a peak level in a mean duration of 17.36 hours, where after that began to decline gradually. The variation between individuals and periods was found significant. The Ig level at the peak ranged between 42.975 and 107.64 mg/ml with a mean of 73.588 mg/ml. The mean Ig level was the highest on the third day. The Ig level declined gradually by 6 – 7 weeks of age reaching a mean level of 25.3279 mg/ml whereafter it began to rise again. There were significant variations in the above trend between individuals and periods. The genetic group had significant effect on the post colostral peak level of serum Ig. The means of Ig level in SM, SAM and SSM kids were, 76.9399 mg/ml, 69.7828 mg/ml and 60.0569 mg/ml respectively. The means of Ig level at the peak was 78.014 mg/ml in single kids, 75.0091 mg/ml in twins and 61.4406 mg/ml in triplets, though the difference were statistically not significant. The positive correlation of 0.2620 noticed between birth weight and post colostral peak level of serum Ig was also not significant. Kids died within two months had significantly lower mean Ig level at the post colostral peak (56.771 mg/ml) than the population mean (73.5881 mg/ml). The mortality rate was 44 per cent in kids with below 70 mg/ml serum Ig and the same was only 3.84 per cent in kids with and above 70 mg/ml of serum Ig. The negative correlation of (- 0.1554) between post colostral peak level of serum Ig and weight gain at 56 days was not significant. The positive correlation of 0.6932 between weekly trend in serum Ig level and body weight during corresponding periods was significant.
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    Evaluation of holstein crossbred bulls based on milk composition of progeny
    (Department of Animal Breeding and Genetics, College of Veterinary and Animal Sciences, Mannuthy, 1997) Radhika, G; Sosamma Iype