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ThesisItem Open Access Effect of planting date, weight of rhizome and spacing on the growth, yield and quality constituents on turmeric (Curcuma longa L)(Department of Horticulture (Plantation Crops & Spices), College of Horticulture, Vellanikkara, 1983) Chatterjee, R K; KAU; Mohanakumaran, NThesisItem Open Access Cytogenetic studies on intervarietal hybrids of sesamum (Sesamum indicum L.)(Department of Agricultural Botany, College of Agriculture Vellayani, Trivandrum., 1984) Chandramony, D; KAU; Krishnan Nair, NThesisItem Open Access Pathology of the reproductive organs in experimental hypothyroidism in goats(Department of Pathology, College of Veterinary and Animal Sciences, Mannuthy, 1982) Nemali Mohan, Reddy; KAU; Rajan, AA survey study was conducted to assess the role of hypothyroidism in the etiology of reproductive disorders in goats. Lowered functional activity of the thyroid was associated with postpartum anoestrum, repeat breeding and delayed puberty. An experimental model of controlled hypothyroid state was induced in goats, using different dose regimes of thiourea with the objective of studying the sequence of physiopathological changes in hypothyroidism and its influence on reproduction. Clinically healthy young and adult cross-bred goats of both sexes were employed for the study. The animals were divided into control, Treatment I (T1) and Treatment II (T2) groups. Groups T1 and T2 were administered thiourea orally at the rate of 50 mg/kg and 100 mg/kg body weight respectively. Clinical symptoms and growth rate were studied. Protein bound iodine, total serum protein and serum cholesterol were estimated. Haematological data were collected and the semen characteristics were evaluated. On the 90th day of the experiment both control and experimental animals were sacrificed leaving at least one animal in each group. These animals were maintained without treatment with thiourea for a further period of 90 days and sacrificed. Cross lesions and histopathological changes in tissues were recorded. Weakness, lethargy, depression, reduced feed intake, subcutaneous oedema of varying degree, loss of libido in males and anoestrum in females were the important clinical features observed. There was stunting of growth and apparent reduction in weight of the animals dosed with thiourea. On discontinuation of treatment with thiourea all the clinical signs manifested disappeared and the animals gained weight progressively. There was significantly decrease in the protein bound iodine, and increase in the total serum protein and cholesterol level in all the animals dosed with thiourea. The values reached the normal level on discontinuation of treatment with thiourea. Microcytic hypochronic anaemia was evident in hypothyroid goats. There was improvement in haemogram values on withdrawal of thiourea administration. Reduction in quantity and quality of semen was observed in hypothyroid goats. The semen appeared normal in quality and quantity on discontinuation of thiourea administration. Gelatinisation of subcutaneous fat and hypertrophy and dilation of the left verntricle were the common findings at autopsy. There was significant increase in the relative weight of the thyroid, pituitary and the adrenal gland. Histologically the thyroid glands exhibited varying degree of hyperplasia and hypertrophy. Predominant histological changes in the pituitary was hyperplasia and hypertrophy of basophil cells and degenerative changes in the acidophils. Adrenal gland showed hypertrophy and depletion of fat in the zona fasciculata. On discontinuation of treatment with thiourea all the lesions disappeared. A significant decrease in the relative weight of the testis and epididymis was observed in all the goats dosed with thiourea. Histologically the seminiferous tubules were small and lined by single layer of spermatogonial cells. Some tubules contained degenerated and desquamated cells without any evidence of sperms. The tubules of the epididymis were small in size and the lining cells showed deciliation and desquamation. These degenerative changes were found to be reversible on discontinuation of treatment with thiourea. The accessory sexual glands, the seminal vesioles and the prostate weighed less in hypothyroid goats. Histologically the cells lining the glands were small inactive, vaculated and hyalinised. After discontinuation of administration of thiourea the reparative changes were almost normal. There was significant decrease in the relative weight of the ovary and uterus in all the animals dosed with thiourea. Histologically ovaries were found to be inactive and only few scattered immature follicles were seen. Uterine glands were few and non secretary type. The lining epithelial cells did not show active mitosis. On discontinuation of treatment with thiourea the weight of the ovary and uterus increased and histologically ovaries and uterus were found to be normal. Kids and female goats were more susceptible to the effects of hypothyroidism. The significant pathological changes observed in the reproductive organs have clarified the importance of hypothyroidism in inducing sub-fertility and infertility in goats. The reversible nature of the lesion was also proved.ThesisItem Open Access Ochratoxicosis in the goat(Department of Pathology, College of Veterinary and Animal Sciences, Mannuthy, 1983) Maryamma, K I; KAU; Krishnan Nair, MAn experimental study was carried out to delineate the pathological effects of ochratoxin in goats. A comparative assessment of ochratoxin production by A. ochraceus and A. sulphureus on what and rice under static and shake cultures was also made. A. ochraceus was found to be a better toxin producing strain in both substrates under static and shake cultures systems and wheat was a better substrate than rice. Toxicity studies were conducted in Sannen – Malabari cross-bred goats of 1 to 3 months age. Purified ochratoxin produced in the laboratory was administered by oral, intra-peritoneal and intravenous routes. The different dose levels adopted were 2.5 mg/kg body weight, 1 mg/kg body weight and 0.5 mg/kg body weight. The synergistic effect of ochratoxin and aflatoxin in goats was studied by adminstering the crystalline toxins simultaneously (Makor Chemicals, Israel) by itraperitoneal route. The parameters of study were: clinical signs, haematological and biochemical alterations, pathological changes in urine, and macroscopic, microscopic and ultra-structural alterations in organs. Varying degree of clinocopathological changes were noticed in the test animals. The animals became weak and listless and in general there was reduction of total erythrocyte count, PCV, haemoglobin and lymphocyte count. Serum protein level was lowered while BUN and creatinine and blood coagulation time were high. There was rise in ALP, SGOT and SGPT in some of the test animals. The changes and degree of variation depended on the dose, total quantity and rate of administration of the toxin and duration of the experiment. More severe alterations were noticed when ochratoxin and aflatoxin were administered simultaneously. Important changes in the urine were lowering of pH, albuminurea and presence of epithelial cells and casts. Pathological changes varied in severity in different organs and were observed in the following descending order: kidney, liver, intestines, stomach, lymph nodes, spleen, thymus, genital organs, endocrines. In the kidneys, the order of intensity of pathological alterations was: proximal convoluted tubules, Henle’s loop, distal convoluted tubule, glomeruli, collecting tubules. Retrogressive changes of different degree and necrosis of the lining epithelial cells of tubules and endothelium and epithelium of glomeruli were the important lesions. Changes in glomeruli and Bowman’s capsule noticed in the higher dose group included shrinkage of glomeruli and presence of proteinaceous material in the capsular space. Eosinophilic granular casts and PAS positive bodies were present in the lumen of tubules. The necrobiotic renal changes were more intense when orchatoxin and aflatoxin were administered simultaneously. Hepatic lesions were mainly fatty infiltration, necrosis of hepatocytes and haemorrhage. The changes were most severe in combined toxicity. Mallory bodies and mild biliary hyperplasia were noticed in a few sections. Necrosis and subsequent depletion of lymphocytes wee the lesions in lymph nodes, spleen and thymus in some test animals. Degenerative changes were also noticed in testis, ovary, pituitary, adrenals and pancreas in experimental groups. In the combined toxicity group the pathological effect was more intense. At the ultra-structural level, the hepatcytes as well as the epithelial cells in the kidney showed severe changes. The cell organelles were either completely damaged or showed partial configurational alterations. Mitochondria showed changed in the density of matrix as well as disorientation and destruction of the limiting membranes and cristae. Cytolysosomes incorporating damaged cell organelles were abundant. Disaggregation of ribosomes and fragmentation of ER were noticed. In the glomerulus, there was destruction of the basement membrane and disruption of the regular arrangement of the foot processes of podocytes. In the cytoplasm of hepatocytes, Mallory bodies and lipid droplets were present. Varying degree of nuclear changes like clumping, condensation and disappearance of chromatin and fragmentation of nucleolus and nuclear membrane were observed. Changes occurred in the tight junctions of epithelial cells of bile ducts. Pathological alterations were more pronounced when ochratoxin was administered by the pwerenteral route. Oral administration of toxin also effected structural alterations which indicated that some fraction of ochratoxin escaped degradation in the rumen. From this study it became evident that aflatoxin potentiated the effect of ochratoxin. The structural damage to the cells might be due to the inhibition of oxidative enzymes which is reflected by the extensive ultra- structural alteration observed in the mitochondria and RER. Biochemical changes like high BUN and creatinine were evidently due to necrobiotic changes in the kidney. Interference in the synthesis of proteins due to damage of hepatic cells and escape of protein molecules due to alteration in the podocyte foot processes and basement membranes may account for the reduced serum protein levels. The nature of organellar destruction and configurational changes in the cells indicate the toxic potency of the mycotoxin on the biological system.ThesisItem Open Access Studies on purple top roll (PTR) of potato in Karnataka(Department of Plant Pathology, University of Agricultural Sciences, Bangalore, 1983) Sreedharan, A; KAU; Reddy, H R1. Survey for the incidence of potato purple top roll revealed that the disease was present in Bangalore, Belgaum, Dharwad, Hassan and Kolar districts of Karnataka. The average percentage of incidence varied from 8.94 to 50.07. The survey also indicated that there was low incidence of the disease in summer and high incidence in kharif and rabi. 2. The pathogen was transmissible by wedge, side and core grafting. 3. The disease was transmitted through dodder, Cuscuta chinensis Lam. 4. The disease was not transmissible through sap and aphids Myzus persicae Sulz. And Aphis gossypil Glov. 5. The etiological agent was transmitted by the leafhopper, Orosius albicinctus Distant and not by Hishimonus phycitis Distant. 6. The vector, O. albicinctus could acquire the pathogen in two hr and inoculate to healthy plants in 30 min. The percentage of active transmission was 35 – 40 and the minimum incubation period in the plant was between 20 and 25 days. Maximum percentage of transmission was obtained on 40th day after inoculation. 7. Characteristic symptoms of the disease was inward rolling of basal parts of top leaflets, purple/pink pigmentation, smalling of leaves, excessive proliferation of axillary buds, erect appearance, production of purple coloured, aerial tubers and stunting and dwarfing of plants. 8. The etiological agent infected tomato, tree tomato, Datura stramonium and D. metel by grafting. 9. The pattern of spread of the disease in the field was from external source in the beginning and later the spread was within. 10. The vector population was correlated with the disease incidence in the field. The increase in the incidence of the disease followed the increase in the vector population. 11. The leafhopper vector, O. albicinctus Distant was high in the months from late June to December and low from January to early June. 12. The high population of leafhoppers was correlated with low temperature and high humidity and low population was correlated with high temperature and low humidity. 13. The disease appeared 40 days after planting in the field and then it gradually increased reaching the peak by 90th day. 14. The pathogen was transmitted through tubers for two successive generations but to a lower percentage in the second generation. 15. Of the 36 cultivars/varieties of potato tested under field conditions, none were found to be resistant, However, the vars. JF 542, JF 4612, JG 676, JG 900, JC 750 and JE 812 had less than five per cent infection. Kufri Chandramukhi and Kufri Jyoti were highly susceptible having 48.3 and 47.6 per cent incidence, respectively. The highest average incidence of PTR in these cultivars in farmer’s fields was 35.85 and 26.03 per cent, respectively. 16. There was considerable loss in yield in many cvs. Viz., JC 750, BS/F 100, JC 182 and EM/F 2120. 17. The weight of tubers produced by the infected plants was always less than the tubers obtained from the adjacent healthy plants. The infected plants produced more number of smaller tubers which aggregated close to the main stem attached on short stolons. 18. Complete remission was obtained at 500, 1000 and 2000 ppm, incomplete remission at 100 and 250 ppm and no remission at 50 ppm of tetracycline given alternatively for 20 days.ThesisItem Open Access Potash nutrition of tapioca (Manihot esculenta Crantz.)(Department of Agronomy, College of Agriculture, Vellayani, 1982) Muraleedharan Nair, V; KAU; Sadanandan, NAn investigation was undertaken at the College of Agriculture, Vellayani and Rice Research Station, Kayamkulam for two years during 1977-79 to study the performance of tapioca (Var. Sree Sahya) under two different agroclimatic conditions. The treatments consisted of three levels of nitrogen (50, 125 and 200 kg N/ha) and three levels of potassium (50,125 and 200 kg K2O/ha) at three times of application. The experiment was laid out in a 3 partially confounded factorial design with two replications.ThesisItem Open Access Biometric analysis of yield and certain yield attributes in the para rubber tree: Hevea Brasiliensis Muell. Arg.(Department of Agricultural Botany, College of Agriculture, Vellayani, 1984) Markose, V C; KAU; Mary, K GeorgeThe para rubber tree, Hevea brasiliensis, is the commercial source of natural rubber. Introduced into the Far East in 1876, from Brazil, commercial cultivation started in India during 1902. The tree has a gestation period of six to seven years. A large number of clones have been evolved through ortet selection and through hybridisation, which show variability for different characters. The present study was undertaken to estimate (1) productivity (2) yield pattern (3) variability (4) correlations (5) effect of yield attributes (6) genetic diversity of twenty clones, and (7) early growth vigour of open pollinated seedlings of selected clones.ThesisItem Open Access Biology, Bionomics and control of coconut cockchafer Leucopholis coneophora Burm.(Division of Agricultural Entomology, College of Agriculture, Vellayani, 1983) Abraham, V A; KAU; Mohan Das, MThe biology of the coconut cockchafer Leucopholic coneophora Burm. was studied in detail for the first time. Techniques for rearing the pests from egg to adult in potted palnts kept in field were standardized. The egg laying behaviour of adults was observed. The morphological changes off eggs, different instars of grubs and pupae during development were studied in detail. The changes in immature stages of male and female insects were traced separately. The general morphology of different instars of the grubs was studied in full with a view to finding distinct identifying characters for each.ThesisItem Open Access Release of soluble aluminum in soils under submerged conditions and its effect on rice(Department of Soil Science and Agricultural Chemistry, College of Agriculture, Vellayani, 1984) Alice Abraham; KAU; Koshy, M MA study has been made of the extent of aluminium toxicity in relation to other important characters in the acid Rice soils of Kerala with a view to evolving suitable ameliorative measures. The submerged wet-land rice soils of Kerala showing a pH value of less than 6.0 were found to contain appreciable amounts of exchangeable aluminium. The aluminium saturation of the total and effective CEC of these soils were also very high and above the critical limits for rice. Flooding of these soils in water resulted in a rise in pH and EC, as well as water soluble and exchangeable iron. Peak values for these parameters were obtained by 20-30 days of flooding, after which the pH remained steady while EC and iron showed a decreasing trend . Water soluble and exchangeable aluminium, on the other hand, registered a significantly lower content after the 6th day and the trend continued till the 30th day.
