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Kerala Agricultural University, Thrissur
The history of agricultural education in Kerala can be traced back to the year 1896 when a scheme was evolved in the erstwhile Travancore State to train a few young men in scientific agriculture at the Demonstration Farm, Karamana, Thiruvananthapuram, presently, the Cropping Systems Research Centre under Kerala Agricultural University. Agriculture was introduced as an optional subject in the middle school classes in the State in 1922 when an Agricultural Middle School was started at Aluva, Ernakulam District. The popularity and usefulness of this school led to the starting of similar institutions at Kottarakkara and Konni in 1928 and 1931 respectively.
Agriculture was later introduced as an optional subject for Intermediate Course in 1953. In 1955, the erstwhile Government of Travancore-Cochin started the Agricultural College and Research Institute at Vellayani, Thiruvananthapuram and the College of Veterinary and Animal Sciences at Mannuthy, Thrissur for imparting higher education in agricultural and veterinary sciences, respectively. These institutions were brought under the direct administrative control of the Department of Agriculture and the Department of Animal Husbandry, respectively. With the formation of Kerala State in 1956, these two colleges were affiliated to the University of Kerala. The post-graduate programmes leading to M.Sc. (Ag), M.V.Sc. and Ph.D. degrees were started in 1961, 1962 and 1965 respectively.
On the recommendation of the Second National Education Commission (1964-66) headed by Dr. D.S. Kothari, the then Chairman of the University Grants Commission, one Agricultural University in each State was established. The State Agricultural Universities (SAUs) were established in India as an integral part of the National Agricultural Research System to give the much needed impetus to Agriculture Education and Research in the Country. As a result the Kerala Agricultural University (KAU) was established on 24th February 1971 by virtue of the Act 33 of 1971 and started functioning on 1st February 1972. The Kerala Agricultural University is the 15th in the series of the SAUs.
In accordance with the provisions of KAU Act of 1971, the Agricultural College and Research Institute at Vellayani, and the College of Veterinary and Animal Sciences, Mannuthy, were brought under the Kerala Agricultural University. In addition, twenty one agricultural and animal husbandry research stations were also transferred to the KAU for taking up research and extension programmes on various crops, animals, birds, etc.
During 2011, Kerala Agricultural University was trifurcated into Kerala Veterinary and Animal Sciences University (KVASU), Kerala University of Fisheries and Ocean Studies (KUFOS) and Kerala Agricultural University (KAU).
Now the University has seven colleges (four Agriculture, one Agricultural Engineering, one Forestry, one Co-operation Banking & Management), six RARSs, seven KVKs, 15 Research Stations and 16 Research and Extension Units under the faculties of Agriculture, Agricultural Engineering and Forestry. In addition, one Academy on Climate Change Adaptation and one Institute of Agricultural Technology offering M.Sc. (Integrated) Climate Change Adaptation and Diploma in Agricultural Sciences respectively are also functioning in Kerala Agricultural University.
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ThesisItem Open Access Characterisation and evaluation of the dwarf cattle of Kerala(Department of Animal Breeding and Genetics, College of Veterinary and Animal Sciences, Mannuthy, 1994) Girija, C R; KAU; Sosamma, IypeThe native cattle of Kerala have been treated as non descript animals always eventhough they possess some special features. The dwarf cattle often called as Vechur were very popular in Central Travancore until 35 years back. With the emergence of the crossbred population of cattle the traditionally reared local cattle have gradually suffered genetic erosion. Under this circumstance, the present work was undertaken to characterize and evaluate the germplasm of local dwarf cattle of Kerala by studying (a) the karyotype and morphology of chromosomes using G-banding (b) the population structure by means of gene frequencies of different blood proteins (c) the growth and production performance. The characterization and the evaluation would help in finding out the genetic differences of the dwarf cattle which will help in deciding about the conservation of their germplasm as a reserve for the future. The dwarf cattle maintained under the ICAR scheme on “Conservation of germplasm of Vechur cattle of the coastal area and the dwarf cattle of the high ranges of Kerala” formed the material for the study. The characterization and evaluation was carried out through the cytogenetic, immunogenetic and polymorphism studies as well as through the description of the growth and production traits. Karyotype analysis was carried out using peripheral blood leukocyte culture technique described by Halnan (1977) and Halnan (1989) with suitable modifications. G-banding of chromosomes were done by the method described by Thiagarajan (1993). Blood protein polymorphism systems such as Haemoglobin and transferring were studied by poly acrylamide gel electrophoresis in horizontal dimension. (Gahne et. al. 1977) with suitable modifications. The statistical analysis of the growth and production data were done as suggested by Snedecor and cochran (1967). The diploid chromosome number of the dwarf cattle was found to be 60, with 29 pairs of autosomes and one pair of sex chromosomes. All the autosomes and the ‘Y’ chrosome were acrocentric. The X chromosome was submetacentric. The relative length of the autosomes ranged from 1.757 to 5.431 per cent. The relative length of the X and Y chromosomes were found to be 5.591 per cent and 2.875 per cent respectively. In the karyological array, the X chromosome occupied the first position. The X chromosome was biarmed and the arm ratio and centromere index obtained were 2.182 and 0.314 respectively. The karyotype and morphometric measurements resembled the finding in Bos indicus group of cattle. The G-banding pattern of chromosomes revealed 72 regions and 314 G-bands. The Y chromosome had 7 G-bands in the ‘q’ arm which resembled the ‘q’ arm of Bos taurus described in the international system for cytogenetic nomenclature of domestic animals. There were two haemoglobin variants HbA and HbB and three phenotypes viz. HbAA, ,HbAB and HbBB , in the population. The heterozygocity was found to be 0.4815. The population was found to be in genetic equilibrium with respect to the Haemoglobin locus. Six transferring phenotypes controlled by three alleles TfA, TfD and TfE were observed. The frequency of TfE (0.359) allele in the dwarf cattle was as high as the frequency of the allele reported in the zebu cattle. The absence of transferring variants like TfF, TfH, TfN and TfG and higher frequency of TfE allele are probably indicative of the genetic isolation of the population from exotic breeds. The absence of TfB and TfF allele which is present in Gir, Hariana, Kankrej, Kangayam, Ongole, Red Sindhi, Sahiwal and Tharparkar also indicates that the dwarf cattle has not inherited genes from the above cattle breeds. The body weights and measurements of calves at birth studied showed that the male calves had a higher body weight (12.55 ± 0.31 kg with a CV of 7.86 per cent) than female calves (10.78 ± 0.40 kg with a CV of 15.02 per cent). The same trend was observed with regard to the birth body measurements also. The heart girth measurement and body weight showed a positive correlation from birth to the 24th fortnight. There is a 100 per cent increase in the birth weight by the 5th fortnight and a three-fold increase by the 10th fortnight. The average daily gain in weight for the four periods I e., fortnights 0-6, 7-12, 13-18 and 19-24 were 0.160 ± 0.011, 0.167 ± 0.018, 0.212 ± 0.011 and 0.139 ± 0.015 respectively for female calves and 0.188 ± 0.023, 0.145 ± 0.016, 0.116 ± 0.025, 0.242 ± 0.049 kg respectively in male calves. During the period from birth to 6th fortnight the growth rates in males and females were similar. The gain in body weight per day during the periods from 7 to 12th and 13 to 18th fortnight was comparatively less for males but the trend reversed during the period of fortnights for 19 to 24th. The average body weights of adult females and males were 126.90 ± 3.56 kg (CV 16.39%) and 210 ± 15.75 kg (CV 14.95%) respectively. The body measurements such as length, heart girth and height (in cms) in females were 97.5 ± 1.12 (CV 5.85%), 115.60 ± 1.32 (CV 5.82%) and 87.53 ± 0.82 (CV 4.82%) respectively. The corresponding figures in males were 111.5 ± 3.77 (CV 6.76%), 146.0 ± 2.92 (CV 3.99%) and 107.5 ± 1.35 (CV 2.50%) respectively. The average body weights and measurements were lesser than those reported in other Indian breeds and crossbred cattle. The total lactation milk production performance of the dwarf cattle was 471.68 ± 38.72 kg (CV 45.29%) in an average lactation length of 217 ± 16.50 days (CV 32.20%). The average daily yield was 2.17 ± 0.11 kg (CV 29.48%). The dwarf cattle attained a peak yield of 3.71 ± 0.16 kg (CV 21.5%) in 23.23 ± 1.703 days (CV 37.38%). The milk production performance eventhough was lesser than crossbreds or some recognized Indian breeds, the milk production in comparison with the body size was reasonable. Considering the morphology of the Y chromosome, the Hb as well as Tf polymorphism and their allelic frequencies, it is to be summarized that the stock of dwarf cattle of Kerala maintained at Kerala Agricultural University is genetically isolated from the other cattle breeds of the country and world. The body size and milk production of the cow indicates its suitability for a farmer who requires milk just for home consumption. The study strongly confirms the necessity of conservation of the dwarf cattle of Kerala which is the smallest variety available in India and perhaps in the world itself.ThesisItem Open Access Prevalence of yeast and yeast like fungi in bovine mastitis and their in vitro drug sensitivity(Department of Microbiology, College of Veterinary and Animal Sciences, Mannuthy, 1995) Sukumar, K; KAU; James, P CThe 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 P$ 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 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 is better for producing milk with more than 8 5 percentage of SNF FS genotype performed better for producing milk having higher percentage of total solidsThesisItem Open Access Parentage control in cattle using blood types(Department of Animal Breeding and Genetics, College of Veterinary and Animal Sciences, Mannuthy, 1992) Mary John, V; KAU; Nandakumaran, BImmunogenetic studies were carried out in four hundred and eleven cross-bred cattle maintained at the University Livestock Farm, Mannuthy and Cattle Breeding Farm , Thumburmuzhi The animals belonged to three genetic groups, viz Jersey cross breds, Brown-Swiss cross breds and Holstein Friesian cross breds The animals were typed for blood group factors and haemoglobin Blood group reagents were produced from iso immune sera, hetero immune rabbit sera and colostrum of an immunised cow Eleven reagents were produced by the above cited methods and seven of them were comparable to international reagents Serum from two animals (Animal Nos 248 and 743) were used as sources of anti J whose titres were being assessed periodically by haemolytic technique The titre varied from 0 to 1 32, but no association with seasons of the year, could be noticed Typing of cross bred animals was done with 28 blood group reagents (14 internationally comparable and 14 new reagents) The internationally comparable reagents were B, Y25 E 3 , C23 R, , F, V, J, L, S, H and Z Anti J from two different sources (Animal Nos 248 and 743) were used and one (Animal No 743) seemed to be the sub type of other (Animal No 248) Standard haemolytic test was carried out for typing animals for their blood group factors The factors occurred in the three genetic groups with varying gene frequencies A good agreement was observed between the observed and expected numbers in each genotypes with respect to FV locus in all the population except in Holstein Friesian cross breds (P < 0 05 ) The mode inheritance of blood group factors showed that the cattle red blood cell antigenic factors were inherited as dominant over their absence The cross-bred population was also typed for haemoglobin Electrophoresis was carried out in poly acrylamide gel Only two haemoglobin variants viz HbA and HbB and three phenotypes viz Hb AA, Hb AB and Hb BB were A observed The gene frequencies of Hb allele was 0 67, 0 6 6 and 0 83 m Jersey cross breds, Brown Swiss cross breds and Holstein Friesian cross-breds, respectively The genotype frequencies at haemoglobin locus for the pooled cross breds were 0 5036 (Hb AA), 0 4307 (Hb AB) and 0 0657 (Hb BB), respectively Genetic variability of breeds was studied m terms of heterozygosity at Hb locus and Friesian cross breds were found to have least heterozygosity, ie 0 282ThesisItem Open Access Biochemical polymorphism in broiler rabbits(Department of Animal Breeding, Genetics and Biostatistics, College of Veterinary and Animal Sciences, Mannuthy, 1990) Usha, A P; KAU; Mukundan, GBlood samples collected from rabbits maintained in the rabbit breeding farm of Kerala Agricultural University formed the materials for this study These blood samples were typed employing horizontal polyacrylamide gel electrophoresis to study the polymorphism of transferrin post transferrin and haemoglobin A total of 152 rabbits comprising of 50 Soviet Chinchilla 52 Newzealand White and 50 local rabbits were involved m the study Genetic inter relationship among growth traits and survivability were studied In all the genetic groups two transferrin variants the faster Tf and slower Tf with two phenotypes TfAA and TfAC were observed The gene frequency of Tf and Tf were 0 7500 and 0 2500 in Soviet Chinchilla 0 8300 and 0 1700 m Newzealand White and 0 8100 and 0 1900 m local rabbits The frequency of TfA allele was higher in all the populations The phenotype TfCC was not observed in any of the genetic groups Three post transferrin phenotypes Ptf FF Ptf FS and Ptf SS were detected and found to be controlled by two F S co dominant alleles Ptf and Ptf The fast moving F variant was designated as Ptf and the slow moving migrant S F was designated as Ptf The gene frequency of Ptf was 0 7400 0 8500 and 0 7600 m the three genetic groups and e that of Ptf was 0 2600 0 1500 and 0 2400 in Soviet Chinchilla Newzealand White and local rabbits respectively Haemoglobin was found to be monomorphic in all the three genetic groups studied The allelic frequencies of transferrin and post transferrin were suggestive of Hardy Weinberg equilibrium in the populations of three breeds No significant diversity was found to exist between genetic groups analysis of segretation pattern observed in pedigrees revealed the autosomal codominant mode of inheritance for transferrin and post transferrin alleles The absence of TfCC phenotype in the whole population of rabbits may be due to its unfavourable influence on the viabilityThesisItem Open Access Genetic studies on the immune response of broiler rabbits(Department of animal breeding and genetics, College of veterinary and animal sciences, 1995) Nandakumar, P; KAU; Mukundan, GThe scope and potential of broiler rabbit production as an alternate source of meat appears to be tremendous taking into account the unique biological attributes of rabbits. However breeding experiments utilising temperate breeds like Newzealand White and Soviet Chinchilla under the humid tropics of the state revealed heavy pre – weaning mortality, high incidence of diseases, sub optimal growth and reproduction. Indirect selection for diseases resistance has been proposed as the most viable approach and immune responsiveness has been suggested as one of the best indicators of disease resistance. Serum gammaglobulin (SG) level, Frossman antibody titer to SRBC, antibody reponse to BRBC, delayed type hypersensitivity (DTH) responses to intradermal injection of phytomitogen PHA – M, and contact sensitivity to DNCB challenge were assessed among 135 breeding rabbits below one year of age and belonging to Newzealand White and Soviet Chinchilla breeds. The effects of breed, sex, sire and body weight on the above immune traits were analysed. Heritability estimates were made for each of the above traits. Association of diseases like coccidiosis, mange and adult mortality with each of the above immune traits was worked out. Association of maternal immune trait status with litter traits was assessed. This research approach was aimed at developing an alternate breeding strategy in the indirect selection for disease resistance, growth and viability. SG level ranged from 9.13 to 84.70 mg/ml with a mean of 28.59 mg/ml. Soviet Chinchilla breed had a significantly (P= 0.048) higher SG level with a mean of 29.51 mg/ml compared to 27.25 mg/ml in Newzealand Whites, differences among males and females were not significant. Sire effects was not significant on SG levels and haritability estimate was 0.1259. Adult body weight had no significant effect on SG level among broiler rabbits. Association of SG level with litter size at birth was not significant. But SG level had a highly significant effect on the litter size at weaning. Correlation of SG level with pre – weaning mortality (- 0.430) was highly significant (P < 0.01) and negative litter weight at birth and at weaning were significantly correlated with SG level among broiler rabbits. No significant association could be observed between SG level and the incidence of mange and adult mortality. But a higher SG level among broiler rabbits was found to be significantly (P = 0.0440) associated with the incidence of naturally occurring coccidiosis. Presence of Frossman’s antibodies to SRBC was confirmed in adult rabbit sera. The Forssman antibody titer (1 + loge) ranged between 1.693 and 5.159 with a mean of 2.776. Breed and sex effects were not significant on Frossman antibody titer to SRBC. Effect of sire on this trait was not significant and the heritability estimate was 0.360. Frossman antibody titer had no significant effect on adult body weight, or litter traits among broiler rabbits. Correlations of Frossman antibody titer of the dam with the litter weight at birth, litter weight at weaning and pre – weaning mortality were not significant. No significant associations could be observed between Frossman antibody titer incidence of mange, coccidiosis and adult mortality. Pre – immunisation titer to BRBC among broiler rabbits was zero indicating the absecnce of Feossman antibodies to BRBC. Antibody titres to BRBC (1+ loge) were 4.594, 4.425 and 4.311 respectively at the first, second and third week post immunisation. The highest antibody response was at the first week, which began to decline gradually. The influence of breed and sex on the antibody response to BRBC were not significant during the first, second and third week post immunisation. Sire effect was highly significant on the antibody response to BRBC during the first, second and third week post immunisation in Newzealand White rabbits. The effect of sire on antibody responses to BRBC was not significant during the first and third week post immunisation in Soviet Chinchilla breed though it was significant during the second week post immunisation. The heritability estimates of antibody responses to BRBC were 0.9200, 0.9400 and 0.9067 respectively during the first, second, and third week post immunisation. The correlations of adult body weight with antibody responses to BRBC during the first, second and third week post immunisation were (-) 0.244, (-) 0.224 and (-) 0.216 respectively. The correlations were highly significant and negative. Antibody responses to BRBC during the first, second and third week post immunisation was not significantly associated with litter traits among broiler rabbits. The incidence of naturally occurring coccidiosis, mange and adult mortality was not significantly associated with antibody response to BRBC. The mean pre – injection skin thickness was 2.140 mm in Newzealand White and 2.224 among Soviet Chinchilla breed. The mean PHA responses at 24, 48 and 72 hours post injection were 2.259, 1.544 and 0.778 mm respectively. Breed effect was not significant on the pre – injection skin thickness or on the PHA responses at 24, 48 and 72 hours. The effect of sex was highly significant in the skin thickness with males having a thicker skin compared to females. The effect of sex on PHA responses at 24, 48 and 72 hours was highly significant with a female superiority for DTH responses to PHA – M. The effect of sires was not significant on pre – injection skin thickness. Sire effects were highly significant on the PHA responses at 24 and 72 hours and approaching near significance at 48 hours in Newzealand White rabbits. However, sire effect was not found to be significant on the PHA responses at 24, 48 and 72 hours post injection among Soviet Chinchillas. Heritability esimates for pre – injection skin thickness, PHA responses at 24, 48 and 72 hours were 0.7637, 0.8600 and 0.6370 respectively. Adult body weight was not significantly associated with the skin thickness and the PHA responses at 24, 48 and 72 hours. Litter size at birth was significantly less in thick skinned does, though weaning litter size was significantly higher in them. PHA responses at 24, 48 and 72 hours had no significant effect on litter size at birth and at weaning or any other litter traits. Pre – injection skin thickness and PHA responses at 24 and 72 hours were not significantly associated with the incidence of mange, coccidiosis and adult mortality. But reduced PHA response at 48 hours significantly pre – disposed the rabbits to body mange. Contact sensitivity to DNCB at 24, 48 and 72 hours post challenge averaged 3.585 mm, 1.796 mm and 1.085 mm respectively. Breed and sex had no significant effect on the contact sensitivity to DNCB at 24, 48 and 72 hours post challenge. Sire effect on contact sensitivity to DNCB at 24, 48 and 72 hours post challenge was not significant in Newzealand White rabbits. Among Soviet Chinchillas also effect of sire was not significant on contact sensitivity to DNCB at 24 and 72 hours, though highly significant at 48 hours. Heritability estimates for contact sensitivity to DNCB at 24, 48 and 72 hours post – challenge were, 0.3820, 0.5490 and 0.3039 respectively. Contact sensitivity to DNCB at 24, 48 and 72 hours post challenge was not significantly associated with adult body weight, litter size at birth and litter size at weaning. Contact sensitivity of the doe at 24 hours post challenge was positively correlated with pre – weaning mortality and litter weight at birth. Lowered contact sensitivity to DNCB at 24 hours had a highly significant effect on the incidence of naturally occurring body mange among rabbit. The incidence of mange was near significant level among broiler rabbits with a lowered contact sensitivity at 48 hours post challenge also. No significant association could be observed with contact sensitivity to DNCB at 24, 48 and 72 hours on the incidence of coccidiosis and adult mortality. Correlations between serum gamma globulin level and Frossman antibody titer to SRBC (0.271) was highly significant correlations of Frossman antibody titer with antibody response to BRBC during the first, second and third week post immunisation was also highly significant. Pre – injection skin thickness had a highly significant negative correlation with PHA responses at 24, 48 and 72 hours. Correlations among PHA responses at 24, 48 and 72 hours were highly significant. Similarly correlation among contact sensitivity reactions at 24, 48 and 72 hours post challenge were highly significant. PHA responses at 24, 48 and 72 hours had significantly high correlations with contact sensitivity to DNCB at 24, 48 and 72 hours post challenge. Prospects of utilising maternal serum gammaglobulin level as a marker in indirect selection for enhanced pre – weaning survivability and growth appears to be promising. Though increased SGlevel was found to be associated with the incidence of coccidiosis, further researches on the coccidial species and host defenses are before establishing a coccidiosis resistance phenotype associated with this trait. The differences in sire effects among the two breeds for antibody response to BRBC and PHA responses are suggestive of the genetic structure of the two breeds, especially the Soviet Chinchilla colony developed from few animals. The significant negative correlation of adult body weight with antibody responses are indicative of lower antibody responses in heavier rabbits. Strong negative correlations between PHA responses and pre – injection skin thickness and a significant effect of contact sensitivity at 24 hours on reducing the litter size at weaning appear to suggest that a low maternal cell mediated immunity might enhance pre – weaning survivability of the kits. Significantly higher incidence of mange among rabbits with a lowered PHA response at 48 hours post injection and contact sensitivity at 24 hours post challenge suggest of an enhanced cell mediated immune response conferring mange resistance.ThesisItem Open Access Genetics of body dimensions of Malabari goats and its cross in Kerala(Department of Animal Genetics and Breeding, College of Veterinary and Animal Sciences, Mannuthy, 1994) Raj, Menon; KAU; Stephen, MathewThe main objectives of this study were: (1) to study the bodyweight and body dimensions of Malabari goats and its Alpine half breds, (2) to estimate the genetic and phenotypic correlations between bodyweight and different body dimensions in various genetic groups and (3) to study any other major factors affecting bodyweights and body dimensions. The study was conducted in 92 goat kids reared at the All India Co-ordinated Research Project on goats farm at Mannuthy, Thrissur. A comparative study was made on the native Malabari with its third generation cross with the exotic Alpine breed. The mean body length, heart girth and height at withers at birth wera 25.68 ± 0.53, 27.37 ± 0.46 and 29.66 ± O. 60 cm and 26.01 ± O. 16, 28.23 ± 0.23 and 30.24 ± 0.45 in male kids of Malabari and Alpine x Malabari crossbreds respectively. In the females the corresponding values were 25.63 ± 0.073, 27.56 ± 0.68 and 25.53 ± 0.48 and 25.3 ± 0.17, 27.60 ± 0.32 and 29.14 ± 0.35 cm. The mean body length, heart girth and height at withers of male Malabari and Alpine x Malabari goats at 60.39 ± 0.81, 59.66 ± 0.82 and 58.18 ± 0.91 12 months were 61.42 ± 0.90, 61.12 ± 0.90 and 59.04 ± 1 . 01 cm and 64. 19 ± O. 81, 64. 60 ± O. 73 and 61. 98 ± O. 9 cm respectively. The corresponding values for females were 58.36 ± 0.81,59.0 ± 0.7 and 58.36 ± 0.72 and respectively. There was no significant difference between the birth weights of- male and female Malabari kids and between the birth weights of the two genetic groups. But the difference was significant in the Alpine x Malabari crossbreds. There was significant difference in the bodyweight at 12 months of age between male and female Alpine x Malabari crossbred kids. No significant difference was observed in the bodyweight at 12 months between the two genetic groups. During the experiment period mean maximum and minimum temperature were 34.55 ± 1.2 and 22.03 ± 1.4 °c respectively. Season had a significant effect on the body weight at six, none and 12 months of age in Alpine x Malabari crossbreds. The effect of type of birth was not significant on the birth weights in Alpine x Malabari crossbreds and Malabari kids. Type of birth had no significant effect on the 12 months body weight in both the genetic groups. analysis showed non-significant Least squares effects of season and sex on the body weights in Malabari kids while in the Alpine x Malabari the effect of sex on body weights was significant at all the ages studied. Season at six, nine and 12 months of age had significant effects on bodyweight in Alpine x Malabari crossbreds Breed had no significant effect on body weights. The heritabilities of bodyweights at various ages were higher in Malabari when compared to Malabari x Alpine crossbreds. The highest phenotypic correlations were observed between the bodyweight and heart girth in both genetic Genotypic correlations between different groups. traits were found to be low at different ages in both the genetic groups. The highest coefficients of determination were observed at the age of six months for both the prediction equations.ThesisItem Open Access Milk protein genetic variants in crossbred dairy cattle(Department of Animal Breeding and Genetics, College of Veterinary and Animal Sciences, Mannuthy, 1995) Madhavan, K; KAU; Nandakumaran, BThe present investigation was undertaken to identify the biochemical polymorphism at different milk protein loci and to establish their inheritance pattern in crossbred cattle. It was also envisaged to analyse the association of different milk protein variants with lactation milk yield and incidence of mastitis. One hundred and thirty five animals belonging to three different crosses of local nondescript cattle viz. crossbred Jersey (50), crossbred Brown Swiss (45) and crossbred Holstein Friesian (40) were typed for milk protein variants by standardising horizontal polyacrylamide gel electrophoresis. The milk protein loci studied were α S1 – casein, β – casein, k- casein and β – lactoglobulin. Two alleles namely B and C with three phenotypes BB, BC and CC were identified at α S1 – casein locus. B allele had the frequency ranging from 0.61 to 0.63. β – casein locus exhibited three phenotypes contributed by two allels A and B. A allele had the highest frequency of 0.81 in crossbred Brown Swiss and it ranged from 0.71 to 0.81 among different crossbreds. Highest frequency of AA phenotype was in crossbred Brown Swiss (0.67) and that of AB phenotype was highest in crossbred Jersey (0.29). Two alleles namely A and B contributed three phenotypes viz., AA, AB and BB at k - casein locus among different crossbreds studied. Crossbred Jersey showed the highest frequency of A allele while crossbred Brown Swiss (0.69) had the highest frequency of B allele (0.44). K – casein AA phenotype had the highest frequency in crossbred Jersey (0.52) and AB phenotypes had the highest frequency in crossbred Brown Swiss (0.51). β – lactoglobulin locus showed two alleles A and B contributing three phenotypes viz., AA, AB and BB. The frequency of A allele was highest in crossbred Holstein Friesian (0.46) and that of B allele in crossbred Brown Swiss (0.60). AA phenotype had the highest frequency in crossbred Holstein Friesian ( 0.25) while crossbred Jersey had the highest frequency of BB phenotype (0.38) and AB phenotype was highest in crossbred Brown Swiss (0.44). The observed and expected phenotypes among different genetic groups at all the four milk protein loci viz. αS1 – casein, β – casein k – casein and β – lactoglobulin were tested by Chi – square test. All the populations studied were in genetic equilibrium with respect to these four loci. This trend is suggestive of neutral role of the three milk protein loci in the population. The genetic variability in the crossbred population was calculated by estimating the heterozygosity was at β – lactoglobulin locus. In the crossbred Brown – Swiss maximum heterozygosity was seen at the k - casein locus. The overall heterozygosity in different crossbred population indicated that the crossbred Holstein Friesian had comparatively highest degree of heterozygosity (0.4603) followed by Crossbred Jersey (0.4346). In crossbred Jersey αS1 – casein types showed significant association with β – casein types. k – casein phenotypes were significantly associated with β – lactoglobulin types. In crossbred Brown Swiss also αS1 – types were found to be linked with β – casein types. β – casein BB phenotype and k – casein variants were found to be linked. β – lactoglobulin phenotypes and β – casein types were also found associated in crossbred Brown Swiss. In the case of crossbred Holstein Friesian all the milk protein variants except β – casein and k – casein were found to be associated. Milk protein variants were not found to be associated with first lactation milk yield or the incidence of mastitis in all the crossbred population studied. The present study could establish the existence of biochemical polymorphism at αS1 – casein, β – casein k – casein and β – lactoglobulin loci crossbred Jersey, crossbred Brown Swiss and crossbred Holstein Friesian cattle studied.ThesisItem Open Access Genetics analysis of body weight and litter traits of pure bred rabbits(Department of Animal Breeding and Genetics, College of Veterinary and Animal Sciences, Mannuthy, 1992) Radhakrishnan, J; KAU; Mukundan, GThe experiment was carried out at the Rabbit Research Station attached to the Centre for Advanced Studies in Animal Genetics and Breeding, Mannuthy. Rabbits belonging to three pure breeds viz. Grey Giant, Soviet Chinchilla and New Zealand White formed the materials for the study. From each breed, seven males were taken and each male was mated to two females each and in all 14 females and seven males were considered in each breed. Seven parameters of reproductive efficiency of the dam were taken and body weights of rabbits born were recorded at four, six, eight, ten and twelve weeks of age. The mean values of body weight at four, six, eight, ten and 12 weeks were highest in Soviet Chinchilla rabbits compared to Grey Giant and New Zealand white, which had the lowest weights among the three breeds. Breed effect was significant for the body weight in all the weeks. The effect of sex on the body weight of rabbit was non – significant in all the three breeds. The sire of the offspring affected the body weight at each stage in all the three breeds. There was also a dam effect on body weight. In general the estimates of heritability were high in all the three breeds. The estimates of heritabilities for body weight show some marked effects of age. In particular, the pre – weaning weights had a high or moderate value compared with the lower estimates obtained for post – weaning weights. Estimates of heritability from the dam component revealed generally larger heritabilities than those of sire component except in New Zealand White rabbits. The phenotypic correlations between the body weights at different ages were positive and generally high, and tended to decrease in value as the differences between the two ages increased. The genetic correlations between body weights for the three breeds showed that all of these relationships were positive, like the corresponding phenotypic estimates. The environmental correlations were generally very high in all the three breeds except in Grey Giant rabbits when estimated based on (Sire + dam) method which may be due to sampling error. It was found that the effect of the breed on the gestation length was non – significant. The breed of the rabbit significantly affected the litter size at birth. Soviet Chinchilla breeds had the lowest litter size at birth. The effect of breed was gain highly significant for the litter size at weaning. Soviet chinchilla rabbits had the lowest litter size at weaning also. Maximum pre – weaning mortality was seen in the Soviet Chinchilla breed though the effect of the breed was found to be non – significant. The highest litter weight at weaning was seen in grey Giant rabbits and the lowest in the New Zealand White rabbits though the number of rabbits alive in New Zealand White breed were more than in the Soviet Chinchilla rabbits. The mean litter weight at weaning was highest in Soviet Chinchilla rabbits. The overall sex ratio was 52 percent. The estimates of heritability for the litter size at birth and at weaning were negative and hence adjusted to zeroThesisItem Open Access Chromosome characterisation of malabari goats and its crosses in Kerala(Department of Animal Breeding and Genetics, College of Veterinary and Animal Sciences, Mannuthy, 1992) Bindu, K A; KAU; Raghunandanan, K VThe chromosome profile of goats was studied with a view to find its number, to prepare the karyotypes of female and male goats of the Malabari and its crosses with Saanen and Alpine and to assess its morphometric values. The experiments were carried out in jugular blood lymphocytes. The cultures were prepared using RPMI 1640 as the medium. The comparative efficacy of different mitogens viz. PHA, PWM and their combination, with different incubation time, revealed that the combination of PHA and PWM at an incubation period of 70.5 h yielded the optimum results. The diploid number of chromosomes in all the genetic groups of goats were found to be 60. Autosomes as well as X chromosomes were found to be acrocentric. The X chromosome was quite prominent in being the longest of all. The Y chromosome was the shortest and the only metacentric in the complement. In karyotypes of the three genetic groups, it was observed that twenty-nine homologous pairs of autosome formed a closely graded seriation. Sexual dimorphism was exhibited with an unequal pair of X and Y chromosomes in males and an equal pair of X chromosomes in the females. The relative length was estimated for each pair of chromosomes in percentage. The X chromosome contributed to more than five per cent of the total complement length in all the three genetic groups. In Malabari, Saanen x Malabari and Alpine x Malabari, the relative length of the Y chromosomes were 1.552+0.10,1.321+0.09 and 1.548+0.10 respectively. The analysis of variance of relative length of X chromosomes revealed a significant difference among the three genetic groups.