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Open Access
Molecular genetic diversity in dwarf cattle of Kerala
(Department of Animal Breeding and Genetics, College of Veterinary and Animal Sciences, Mannuthy, 2003) Suprabha, P; KAU; Anilkumar, K
This study was undertaken for finding the molecular genetic diversity among dwarf cattle groups of Kerala namely Vechur, Highrange dwarf, Vatakara and Kasargode using RAPD-PCR technique. Genomic DNA was isolated from 101 animals belonging to the four cattle groups using phenol: chloroform method. The mean yields of DNA isolated from five ml of whole blood was 110.07 ± 9.4 ug and the average ratio between optical densities at 260 and 280 nm was 1.6. The PCR conditions were standardized with respect to annealing temperature (382c), magnesium chloride concentration (1.5 mM) and the amount of Taq DNA polymerase (0.5 units/20 Ill). RAPD-PCR analysis was performed in pooled DNA samples using 26 random oligonucleotides. Individual sample analysis was done by selecting ten primers. The degree of polymorphism obtained for the primers varied from 0 to 100 per cent in different populations. The polymorphism of primers ILO 876, ILO 1127, OPA 20, OPA 12, OPA 09 were higher for all groups tested. ILO 526, OPA 10, OPA 01 and OPA 18 gave moderate levels of polymorphism whereas the polymorphism given by OPA 06 was very low. The primer [LO 1127 produced a distinct band which was present in half of Vechur animals and in one Kasargode cattle. ILO 526 gave a low degree of polymorphism in Kasargode cattle and moderate levels in other groups tested. A predominant population specific band of 2.5 kb was identified in Highrange dwarf cattle with primer OPA 06. When amplified with OPA 20, a band (OPA 20 c) was noticed in Vechur animals with a frequency 0.07 and it was absent in other animals. The primer OPA 18 produced two common bands and the primer OPA 06 produced eight common bands. OPA 014, OPA 09 g and OPA 12 g were the common bands present in all the animals tested when respective primers were used. The band sharing values obtained were higher for Vechur and Vatakara animals (0.83 ± 0.00) and lower for Highrange dwarf and Kasargode animals (0.81 ± 0.00), when within group band sharing was considered. The between group band sharing value varied from 0.80 ± 0.00 (between Highrange dwarf and Kasargode) to 0.83 ± 0.00 (between Vechur and Vatakara). This indicates that Vechur and Vatakara populations are more similar than Highrange dwarf and Kasargode cattle. The least squares analysis of variance of band sharing value showed significant effects (Pprimer on band sharing. The percentage difference values calculated as a measure of genetic divergence between groups were not significantly different between Vechur and Vatakara and between Highrange dwarf and Vatakara. They differed significantly between comparisons of Vechur-Highrange dwarf, Vatakara-Kasargode, Vechur-Kasargode and Highrange dwarf-Kasargode combinations. The mean average percentage difference calculated as a measure of genetic dissimilarities between groups, ranged from 17.93 (between Vechur and Vatakara) to 20.92 (between Highrange dwarf and Kasargode). The genetic distance calculated was lowest between Vechur and Vatakara (0.006) and highest between Highrange dwarf and Kasargode (0.046). The dendrogram prepared showed mixing of animals of different genetic groups. In the present study the molecular genetic diversity among four genetic groups of dwarf cattle in Kerala was estimated using the RAPD-PCR technique. It was observed that the Vechur and the Vatakara animals are genetically more similar than the Highrange dwarf and Kasargode animals.
Open Access
Genetic evaluation of litter traits and viability of desi pigs
(Department of Animal Breeding and Genetics, College of Veterinary and Animal Sciences, Mannuthy, 2003) Kowsigaraj, P; KAU; Rajan, M R
In a six month study ninety six Desi piglets born in the same period and year were observed for evaluation of certain litter traits, association of gammaglobulin with incidence of disease symptoms and morphological differences based on body measurements. The average birth weight, weaning weight, litter size at birth and weaning, litter weight at birth and weaning were 0.827 ± 0.020 kg, 6.36 ± 0.156 kg, 8 ± 0.520, 6 ± 0.325, 6.621 ± 0.477 kg and 38.160 ± 2.48 kg, respectively. Influence of different factors on birth and weaning weight were worked out by Least squares analysis of variance. The pre-weaning mortality was 25.865 ± 3.107 per cent. The mortality percentage was worked out with respect to birth weight and the causes for the mortality were recorded based on post mortem findings. Maximum mortality occurred in piglets with 0.5 kg weight and below at birth. Gastro-enteritis and pneumonia were found to be the common causes ofpre-weaning mortality. The body weights and body measurements up to 180 days were recorded at monthly intervals. The average body weight at sixth month of age was 25.670 ± 0.250 kg. Maximum growth rate was found from the fourth to sixth month. Body weights and body measurements were positively correlated at all ages. The post- weaning body weight was most influenced by body length. The total body surface area of Desi and Large White Yorkshire pigs were computed by dividing the body into different geometrical figures. Desi pigs excelled the Large White Yorkshire in surface area per kg body weight and the difference was significant (Pgarnmaglobulin was estimated by Zinc Sulphate Turbidity Test and the factors influencing its level were determined by Least squares analysis of variance. Sire, litter size and incidence of diarrhoea had significant (P<0.05) association with serum gammaglobulin level. Serum gammaglobulin level was positively correlated with post-weaning body weights.
Open Access
Utilization of half-sibs information to increase the accuracy of young bull selection
(Department of Animal Breeding and Genetics, College of Veterinary and Animal Sciences, Mannuthy, 2003) Sajeev Kumar, T; KAU; Stephen Mathew
The present study was conducted to compare the breeding values of bulls in different sire evaluation methods and to explore the possibility of information on dam's yield and half-sibs in sire evaluation methods utilizing the data from Progeny Testing Scheme of KLD Board. Total 25 bulls, which had minimum of fifteen progeny and ten half-sibs were used. Out of 1212 records, progeny and half-sibs had 847 and 365 respectively distributed in 43 centres. The overall mean of first Lactation milk yield (FLMY) of progenies, half-sibs and both together were 2389.0 ± 23.46, 2131.0 ± 36.34 and 2311.3 ± 20.00, kg, respectively. Different centres and years of calving exerted significant effect on FLMY but season and age at first calving did not influence FLMY. Heritability estimate of FLMY was found to be 0.221 ± 0.077. Estimated sire merit (ESM) of bulls were estimated using ten indices viz. based on performance of dam (M), based on performance of paternal half-sibs (HS), based on performance of dam and paternal half-sibs (M+HS), based performance of dam, paternal half-sibs and progeny (M+HS+P), simple daughter average (SDA), contemporary comparison (CC), least squares (LS), KLD Board method, BLUP without considering relationship of sires (BLUP-l) liand BLUP considering relationship of sires (BLUP-2). The range ofESM were '+62.8745 to +396.8055, -157.169 to +287.358, -24.591 to +316.516, -193.877 to + 307.601, kg for M, HS, M+HS and M+HS+P respectively. The SDA and ESM of CC ranges were 2153.8 to 2663.2 and -1628.80 to 1876.58, kg respectively whereas CC index ranged from -258.79 to +406.74, kg. The ESM of LS, KLD Board, BLUP-I and BLUP-2 ranges were -450.92 to +567.69, _ 111.83 to +513.78, -329.8 to +370 and -332.8 to +362.6, kg, respectively. Rankings of sires by different methods were not the same but ranking by SDA, LS and KLD Board method was almost similar with rank and product-moment correlations around one. Ranking by CC, BLUP-l and BLUP-2 were similar with very high rank and product-moment correlations. The average standard error (SE) of SDA, LS, KLD Board, BLUP-l and BLUP- 2 were estimated. BLUP-J followed by BLUP-2 had lowest SE and SDA had the highest. The results are suggestive of opting for BLUP procedures for sire evaluation in Kerala. Additional information on dam and half-sibs did not have much advantage if more progeny records are available for sire evaluation.
Open Access
Chromosome architecture of desi pigs of Kerala
(Department of Animal Genetics and Breeding, College of Veterinary and Animal Sciences, Mannuthy, 2001) Jayan, K C; KAU; Raghunandanan, K V
A cytogenetic analysis of the chromosomes of black desi pigs of Kerala was carried out. Fifty four black desi pigs housed at the AICRP on pigs: centre for Pig Production and Research, Mannuthy formed the material for study. Forty five Large White Yorkshire pigs were also studied for comparison of the chromosome architecture. Metaphase spreads were obtained by peripheral blood leukocyte culture in RPMI 1640 medium. A combination of pokeweed nitrogen and phytohemagglutinin was used for initiating mitosis. The metaphase spreads were G-banded by incubating them in 2 x SSC containing trypsin solution for 45 minutes at 60°C. The number, morphology and morphometric measurements of chromosomes were studied. The distinct visible bands observed in G-banding was compared to that of the standard G-banded karyotype of pigs. The karyotype revealed in desi pigs a chromosome diploid number of 38 (2n = 19). This consist of six pairs of submetacentric chromosomes, four pairs of metacentric chromosomes, six pairs of acrocentric chromosomes and a pair of sex chromosomes, either XX or XY. The X-chromosome was submetacentric and Y-chromosome metacentric. In Large White Yorkshire pigs included in the present study also the diploid number of chromosomes is 38, with similar morphological characteristics for the chromosomes as that of the desi pigs. Thus in morphology and number of chromosomes, the desi pigs maintained a similarity to that of large White Yorkshire pigs. The relative length of the largest chromosome which was a submetacentric one in both breeds was 11.69 ± 0.19 in desi pigs and 11.35 ± 0.37 in large White Yorkshire pigs. The Y-chromosome was the smallest chromosome in desi and large White Yorkshire pigs. The Y-chromosome had a relative length of 1.95 ± 0.12 in desi pigs and 1.7 ± 0.07 in large White Yorkshire pigs. The relative length of X-chromosome of desi and large White Yorkshire pigs were 4.63 ± 0.25 and 5.01 ± 0.22 respectively. The arm ratio of the submetacentric chromosomes was highest for chromosome 2 in both the breeds. The arm ratio was lowest for chromosome 8 in desi pigs and chromosome 5 in large White Yorkshire pigs. The ann ratio of the X-chromosome was 1.97 ± 0.08 for desi pigs and 1.81 ± 0.15 for the large White Yorkshire pigs. The centromeric index measurements varied from 23.06 ± 0.84 to 42.68 ± 0.71 for desi pigs and 26.2 ± 0.89 to 39.45 ± 1.51 for large White , Yorkshire pigs. The centromeric index value was highest for chromosome 8 and lowest for chromosome 2 in both breeds. The X-chromosome had a Centromeric Index of 32.09 ± 1.17 in desi pigs and 36.33 ± 1.64 in large White Yorkshire pigs. The bands obtained by G-banding of the chromosomes of desi pigs were comparable to the standard G-banded karyotype of pigs.
Open Access
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; KAU; 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
Open Access
Polymorphism of growth hormone gene in Malabari goats (Capra hircus)
(Department of Animal Breeding and Genetics, College of Veterinary and Animal Sciences, Mannuthy, 2002) Chitra, R; KAU; Aravindakshan, T V
Malabari 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 in milk production, growth rate and fecundity. The growth hormone (GB) gene is a potential target for studies of molecular variation because of its possible direct or indirect effects upon growth, lactation and mammary gland development in dairy animals. The polymorphism in the third intron of GH gene was investigated by polymerase chain reaction (peR) and restriction endonuclease digestion. Genomic DNA was isolated from a random sample of 196 genetically unrelated Malabari 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 ug. The ratio of optical densities at 260 and 280 nm was above 1.7 indicating good deproteinisation. Oligonucleotide pnmers based on bovine sequences were used for amplification ofGH 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 MspI restriction enzyme revealed two alle\es viz., Mspi (+) and MspI (-) with gene frequencies of 0.70 and 0.30, respectively. In the Malabari goats tested in this study only (+1+) and (+1-) GHIMspI genotypes were encountered where as none of the animal was of the (-1-) genotype. [t is suspected that the MspI (-) 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 w.ith respect to morphological and other phenotypic characters. Studies on the association of GHIMspJ genotypes with growth and milk traits in Malabari goats revealed the following results. The (+1-) genotype was superior to (+1+) genotype with respect to milk protein percentage in population-I, The (+1-) genotype was found to be associated with significantly high milk SNF percentage in population II and pooled population. The GHIMspI genotypes did not exhibit significant effect on body weight, body measurements, peak milk yield, milk fat and the litter size. The different population groups differed significantly with respect to body weight, body measurements like length, heart girth and height at withers, peak milk yield and I 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 MspI polymorphism using PeR-based procedure is a very efficient way to identify the GH genotypes in Malabari goats.
Open Access
Genetic and environmental factors influencing growth rate and body weights up to six months in Malabari goat
(Department of Animal Breeding and Genetics, College of Veterinary and Animal Sciences, Mannuthy, 2003) Jithendrakumar, K B; KAU; Rajan, M R
Goats contribute a major share of the meat produced in India so it is worthwhile to evolve and propagate meat type goats suited for the humid tropics of India particularly to Kerala state. Malabari goat has got high adaptability, crude fibre conversion efficiency and prolificacy. So breeding programs can be developed on that breed to evolve meat type. The effects of sex, type of birth, month of birth, sire and dam's body weight at kidding on birth, weight, weaning weight, weight at 180 days and body weights at fortnightly interval in 113 Malabari kids were assessed. Heritability estimates were made for body weight at different ages. Correlations were worked out on body weights, milk yield and dam's body weight at kidding. This research approach was aimed at ascertaining the feasibility of evolving a selection criteria for the development of a meat type goat. Overall means for birth weight, weaning weight and weight at 180 days were 1.79 ± 0.046, 6.48 ± 0.211 and 11.04 ± 0.322 kg respectively. Sex had a significant effect on birth weight, weaning weight, weight at 180 days, pre- weaning and post-weaning body weights. Means of birth weight, weaning weight and weight at 180 days for male kids were 1.87 ± 0.059,6.77 ± 0.267 and 11.79 ± 0.407 kg and that of females were 1.73 ± 0.046,6.19 ± 0.252 and 10.29 ± 0.384 kg respectively. Males were found to be heavier than females at all stages of growth. Birth type of kids had significant effect on birth weight and pre-weaning body weights and no significant effect was found on weaning weight, post- weaning body weights and weight at 180 days. Means body weights for single, twins, triplets were 2.03 ± 0.070, 1.83 ± 0.049 and 1.54 ± 0.096 kg at birth, 6.96 ± 0.319, 6.46 ± 0.226 and 6.01 ± 0.435 kg at weaning and 11.27 ± 0.487 kg, 10.80 ± 0.344 kg and 11.06 ± 0.664 kg at 180 days of age. Single born kids were found to be the heaviest followed by twins and triplets at birth and weaning. At 180 days of age singles were found to have higher weight, followed by triplets and twins. Singles had higher weights in pre-weaning growth followed by twins and triplets where as twins and triplets showed a compensatory growth in the post-weaning period. Month of birth had a significant effect on pre-weaning weights where as the effect was not significant on birth weight, weaning weight, post-weaning weight and weight at 180 days. Kids born in May, June, July and August had higher weights in pre-weaning growth than those born in September, October, November and January. Sire effect was found to be non significant on body weights at all ages. Heritability estimates of birth weight, weaning weight and weight at 180 days were 0.30 ± 0167, 0.35 ± 01n and 0.35 ± 0.276 respectively. Dam's body weight at kidding was found significant on body weights from 168 days only. Birth weight had significant correlation (0.534) with weaning weight. A significant correlation (O.2()5) was found between weight u\ Wl'llnillg uud IHO d:lY~. Correlations between Birth weight and weight at 180 days was not significant. A significant correlation also noticed between milk yield and the pre-weaning body weights of kids. Correlation of dam's body weight with milk yield (0.379), litter size (0.477) and litter weight (0.558) was found to be significant. Singles had higher body weight from birth to weaning followed by twins and triplets. But it was observed that there was no significant difference among kids of different type of birth in the post-weaning period. The triplets had a compensatory growth during the post-weaning period. Dam's weight at kidding influenced body weight of kids from 168 days. The present study reveals body weight of the mother is the major factor, which decides the type of birth. Higher the weight at kidding larger will be the litter size and level of production of milk. So based on the above result it is suggested that the selection to evolve the meat type of breed should be directed towards type of birth. Body weight of dam is a prime trait to be considered in selection by which the litter size, milk production of dam and body weight of kids at the age of slaughter could be improved.
Open Access
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; KAU; 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.
Open Access
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; KAU; 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.

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