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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 Studies on induced mutations in rice (Oryza sativa L.)(Division of genetics and plant breeding ,Agricultural college and research institute , Coimbatore., 1971) Gopinathan Nair, V; KAUThesisItem Open Access Studies on the burrowing nematode radopholus similis (cobb,1893) thorne 1949 on pepper(Piper nigrum L.) and its role in slow wilt disease(Department of plant pathology, University of agricultural sciences, Bangalore, 1976) Venkitesan, T S; Setty, K G HThesisItem Open Access Exploration of the feasibility of developing races of trichograma Australicum girault ( trichogramatidar, hymenoptera) suitable for different environments(Division of entomology ,Agricultural college and research institute ,Vellayani., 1970) Abraham, C C; KAU; Pradhan, SThesisItem Open Access Studies on certain gastro-intestinal nematodes with special reference to those found in goats(Department of parasitology, College of Veterinary and Animal Sciences, Mannuthy, 1980) Sathianesan, V; KAU; Kalyanasundaram, RLife history of Triohuris globuloss has been elucidated for the fist time using kids !q as experimental animals. Both free living and parasitic stages have been described in detail with illustrations. The prepatent period of Triohuric globuloss was found to be 85-89 days. T.globulosa failed to develop in guniea pig on experimental transmission. Haematology and histopathology of trichuriacis in kids experimentally infected with T.globulosa have been studied for the first time and heavy infection with the worm was found to cause anaemia and pathology changes in cacum of the host. Prepatent period of Strongyloides napillosus in kids infected orally with 7000 larva has been determined for the first time to be 6-7 days. Neoasoais vitulorum of calves has been found to be not transferable to oat either transplacentally or orally. In gunia pigs M.Vitulorum failed to attain sexual maturity. Calves could not be infected with infected with M.vitulorum post-nataly. Oesphagostomum colubianum of goats has been found to be not transferable to calves. Prepatent period of O.colusbionum in kids infected experimentally was found to be 40 days. Comparative efficacy of 4 anthelminties viz., Oxibendazole, thiophanate, Albendazole and Parbendazole was increased by conducting treatment trials. Against monospecific infection of Trichuris globulosa in experimentally infected kids the efficacies of Oxibendazile, thiophanate, Albendazole and Parbendazole at the recommended doses of 10mg.50mg, 10mg and 30 mg/kg body weight respectively were found to be 48.6%, 41%,47.3% and 49.3% respectively. Even at double the recommended doses the anthelminations were found to be well tolerated by the kids. Oxibendazole and Albendazole at the rate of 10mg and 10mg/kg body weight respectively were found to be 100% found to be 100 % effective against colubriformise, effective against respectively were Haemonohus contortue, trichostrongylus .Thiopanate at the recommended dosage (59mg/kg body weight) was also 100% effective against all he nematodes mentioned above except Haemonous contortus against which it was only 97% effective at that dosage. Parbendazole at the recommended dosage shedule (30mg/kg body weight) was 100% effective against the nematodes with the exception of .against which only 86.6% efficacy was noticed. Against in nature nematodes in the gastro-intestinal tract Oxibendazole and Albendazole were 100% effective whereas the efficacies of P`arbendazole and thiophanate were 85% and 74% respectively at their recommended doses. In in vitro studies the anthelmintic efficacy of Oxibendasole against Haemonchus contortus was found to be superior to that of the remaining anthelminties. In ovicidal property also, Oxibendazole was better than all the others, since it was ovicidal in 6 hours after administration whereas albendazole, thiophanate and Parbendazole were ovicidal in 8 hours, 9 hour and 11 hours respectively. Albendazole was found to be superior to al the other 3 anthelmintion in their influences on the body weight gain of treated animals closely followed by Oxibendazole. Perbendazole and thiophanate were inferior to others Judging on the basis of over all efficacies Oxibendazole and Albendazole were found to be superior to thiophanate and Parbendasole. Treatment trials with Oxibendazole, Albendazole and thiophanate against gastro-intestinal nematodes of goats have not been attempted earlier than the present study.ThesisItem Open Access Genetic studies in sweet potato (ipomoea batatas(l.)lam.) a biometric approach(Department of Agricultural Botany, College of Agriculture, Vellayani, 1979) Joseph, C A; KAU; Mary George, KIn a varietal evaluation of 40 varieties of sweet potato all the 15 characters studied showed highly significant differences among the varieties. This was also expressed in the higher phenotypic and genotypic coefficients of variation. The high degree of variability especially in tuber characters offers scope for recombining desirable genes from different varieties. Tuber yield showed significant positive correlation with number of tubers, tuber diameter and harvest index, and significant negative correlation with internode length, vine length and top weight. Path-coefficient analysis revealed that among the first order components of tuber yield, tuber diameter, length and number and top weight had high positive direct effects while leaf area index had a negative direct effect. A comparison of the direct and indirect effects of first and second order components revealed that while selecting for high yielding types, a balanced approach may be adopted with regard to the different yield attributes. Genetic divergence in the available germ plasm was estimated using the Mahalanobis' D2 statistic and based on this the 40 varieties were grouped into 12 clusters. The number of verities in each cluster ranged from one to eight. The divergence between different clusters was not always due to divergence in the same set of characters but a combination of different sets of characters. Out of the fifteen characters studied seven viz., tuber diameter, vine length, number of branches, number of tubers, tuber yield, top weight and number of leaves accounted for more than 80 per cent of the divergence in the material. Canonical analysis also more or less confirmed the grouping of the verities made by Tocher's method. Eight varieties selected on the basis of genetic divergence were used for progeny studies. All these varieties were found to be completely self-incompatible. It is observed that time of pollination markedly affected fruit and seed set. Maximum fruit and seed set was obtained between 7 and 7.30 a.m. And it progressively decreased as time passes. The weather conditions prevailing during the period of anthesis and pollination also influenced fruit and seed set. Maximum, minimum and mean temperature had significant negative correlation with both fruit and seed set. Path-coefficient anaysis revealed that most of the weather elements studied had negative direct effect on fruit and seed set. The total contribution of weather elements alone on fruit and seed set worked out to 40 and 32.5 percent respectively and hence any study on incompatibility and sterility in sweet potato may be conducted under controlled environmental conditions for reliable results. Genetic analysis of quantitative characters was done utilising line x tester and open pollinated progenies of the eight selected varieties. In the open pollinated progenies, existence of non- additive and environmental effects were observed in top weight, vine length, tuber diameter and leaf area index, and additive effects in number of leaves, number of tubers and tuber yield. In the line x tester progenies, additive variance was high compared to non- additive components in all the characters except the number of branches. The regression coefficients of progenies on male and mid- parental values were significant in seven out of ten characters in the line x teater progenies and in four characters on female parental values in the open pollinated progenies. The standardised regression coefficients reduced the magnitude and variability in the regression coefficients to some extent. The estimates of broad sense heritability from the varietal evaluation was higher in magnitude for most of the characters than the estimates of narrow sense heritability obtained from components of variance in open pollinated and line x tester progenies. Tuber yield showed 70.61 and 43.65 per cent heritability from the components of variance analyses in the open pollinated and line x tester progenies respectively, while number of tubers showed 82.75 and 70.07 per cent heritability. The variance between males was significant in respect of top weight, vine length, number of leaves, number of tubers, tuber diameter, leaf area index and harvest index, while the variance between females was significant only in tuber length. Significant reciprocal differences were observed in top weight, number of tubers, leaf area index and harvest index. With respect to general combining ability significant positive effects were observed in number of tubers in the varieties J.29 and H.42, tuber length in Palchakram and H.42, tuber diamter in IB.40 and Chakkaravalli and harvest index in J.29 and Palchakram. Significant heterotic effects were observed in a number of vine and tuber characters in both hybrid and open pollinated progenies. Seven hybrid progenies showed significant increase in tuber yield which ranged from 31.25 to 84.63 per cent over the higher parental values. Both hybrid and open pollinated progenies gave heterotic combinations for economic characters. The varieties which gave heterotic progenies by open pollination have performed well in certain hybrid combinations also. Considering the difficulties in the large scale hybridization and production of hybrid seedling, it is suggested that open pollination in selected varieties especially good combiners can be adopted as a quick and efficient method for varietal improvement in sweet potatoThesisItem Open Access Optimization of agronomic resources for maximizing grain and mill yield of rice(Department of Agricultural Engineering, Indian Institute of Technology, Kharagpur, 1976) Kannan, Mukundan; KAU; Pande, H KAn investigation was planned during the main growing season, i.e., ‘aman’ (June to November ) to find out the optimum levels of the major inputs for rice cultivation such as nitrogen, phosphate, and water, associated with the management practices like optimum time of harvest, in order to maximize production and to obtain quality paddy which, when processed, should give a high quality rice and thereby high economic return. Keeping the above points in view, four field experiments were conducted during two consecutive ‘aman’ seasons of 1972 and 1973 in a cultivators’ field at abhoy Ashram, Balaramapur which is located about 3 km south – east of the Institute. The farm soil was silty – clay – loam, having a pH of 8.1. The experiments were conducted with the high – yielding rice variety IR 22 to study its performance under three levels each of nitrogen, phosphate and submergence and laid out in 3 x 3 x 3 confounded design. Nine additional plots to accommodate ‘o’ levels of nitrogen and phosphate were included for fitting production functions. In the first year of experimentation, the nitrogen and phosphate levels were 60, 120 and 180 kg/ha and 30, 60 and 90 kg/ha respectively. In the second year, the levels were 60, 90 and 120 kg N/ha and 30, 45 and 60 kg P2O5/ha. The modification in the levels of nitrogen and phosphate, in the second year, were made on the basis of the findings of the first year of experimentation. In both the years, the levels of submergence were kept constant, i.e., 0 – 5 cm, 5 + 2 cm, and 10 + 2 cm. For finding out the optimum grain moisture at harvest, suitable for higher milling yield, the crop was harvested at 25.5 – 22.5, 22.5 – 19.5 – 16.5 and 16.5 – 13.5 per cent grain moisture. The optimum levels of each input for maximizing grain yield and head yield were found out by fitting production functions. To identify a suitable variety under a specific management of production and processing, four high yielding rice varieties – Sona, Jayanthi, Pankaj and IR 22 were grown in ‘aman’ season of 1972 and 1973 with similar levels of nitrogen and phosphate as mentioned in Experiments 1 and 2; an additional treatment, with nitrogen and phosphate at ‘o’ level was also included. These experiments were laid out in 4 x 4 x 4 confounded design. The crop was grown under continuous submergence of 5 +2 cm and was harvested at grain moisture content ranging between 19.5 and 16.5 per cent. Treatment wise experimental details and the salient findings are given in the following pages. Positive response with reference to grain yield, total mill yield and head yield of variety IR 22 was noted up to 90 kg N/ha and 45 kg P2O5/ha. Further increase in nitrogen and phosphate levels to 120 kg/ha and 60 kg/ha respectively did not and its percentage was minimized by harvesting the crop above 19.5 per cent grain moisture or between 26 and 30 days after flowering. However, by increasing the level of nitrogen from 90 to 120 kg/ha and 120 to 180 kg/ha, the head yield and its recovery percent was less affected even when the crop was harvested with some delay, i.e., between 19.5 and 16.5 per cent grain moisture or between 35 and 37 days after flowering. The influence of phosphate on grain yield and milling quality, particularly head yield recovery percentage, was more pronounced when considered in combination with grain moisture at harvest. A suitable water management practice, of growing the crop with shallow submergence of 5 + 2 cm was found beneficial in increasing the yield as well as the milling and head yields. The influence of submergence on the head yield recovery percentage was, however, not to the same extent as that of nitrogen and grain moisture at harvest. On fitting the function, for variety IR 22, it could be ascertained that maximum grain yield to the extent of 5112 kg/ha can be attained with the optimum levels of 119 kg N/ha, 59 kg P2O5/ha, 149 cm of water and 22.4 per cent grain moisture at harvest which corresponded to harvesting the crop about 30 days after flowering. On the other hand, maximum head yield to the extent of 3562 kg/ha can be attained with the optimum levels of 124 kg N/ha, 51 kg P2O5/ha, 159 cm of water and around 26 per cent grain moisture at harvest which corresponded to harvesting the crop about 26 days after flowering. The grain yield and consequently, the gross and net returns were maximum under the same levels of nitrogen, phosphate, submergence and grain moisture at harvest. However, from an assessment of rough rice and polished rice along with broken, bran and husk, it was ascertained that the increase in net return to the extent of 984 k/ha was possible only by processing the rough rice. The positive response in grain yield of all the varieties was found only up to 90 kg N/ha and 45 kg P2O5/ha. In varietal comparison, grain yield, mill yield, head yield and net return were found to be maximum in case of the variety Pankaj, amounting to 5192 kg/ha, 3768 kg/ha, 3027 kg/ha and 1716 Rs/ha respectively. The variety Pankaj was followed by IR 22, Sona and Jayanthi in order. However, in milling quality, particularly head yield recovery percent, IR 22 was found superior to all the other varieties. Further, the variety IR 22, with along and slender grains, proved superior in quality to Pankaj, with long and bold grain. The former, eventually, has higher market value that brought higher return. These characteristics in IR 22 narrowed the difference in profit, when compared to Pankaj, though the latter has significantly higher grain yield the additional net return over milled rice was estimated at 877 Rs/ha in case of IR 22 and 833 Rs/ha in case of Pankaj. The agro – climatic conditions of this region of West Bengal, where rice is the only crop during ‘aman’, provide better prospects for cultivation of variety IR 22 as well as Pankaj. In quality criteria as well as growing period, IR 22 may prove superior to Pankaj. Their cultivation for higher yield and quality rice is possible only through suitable levels of fertility and water inputs as well as management input which includes the timeliness of operations, particularly harvesting, because it has a greater impact on the final outturn of the produce as quality rice.ThesisItem Open Access Postnatal development of testis and epididymis, semen characteristics and fertility of brown- swiss crossbred bulls(Department of Animal Reproduction and Gyneacology, College of Veterinary and Animal Sciences, Mannuthy, 1981) Surendran Varma Raja, C K; KAU; Ramachandran Rao, AA systematic investigation involving the use of 24 Brown Swiss crossbred bull calves and 7 adult bulls with 62.5% exotic inheritance varying in age from 0- 360 days and 22-40 months respectively, resred and maintained at Indo-Swiss Project, Mattupatty, Kerala, was carried out in order to (a) trace the postnatal growth and development of the testis and epididymis and (b) assess the semen characteristics such as volume, initial motility, sperm concentration, live sperm count and incidence of abnormal sperms; As a corrolary to and as an integral part of this comprehensive study, 6679 semen collection particulars from the records maintained at the Indo-Swiss Project, Mattupatty and 7586 insemination data at the Crossbreeding Research Centre, Muvathuphza werecritically scrutinised to deduce freezability/discard rate of the ejaculates and the fertility potenoy of the bulls, respectively. The materials used, the salient observations made and the valid inferences drawn aare given below: Twenty four pairs of testis and epididymis collected from the bull calves were processed to study the postnatal growth and development. The pattern of growth of testis and of the epididymis was found to be curvilinear. The testicularand epididymal weights were observed to be significantly (p<0.01) correlated with the age, and body weight of the animals. A highly significant (p<0.01) correlation between epididymal weight and testicular weight was also observed. The growth rate of the seminiferous tubules appeared to be of sigmoid type. Formation of lumen in the seminiferous cords was initiated at 150 days and completed, at 180 days of age. The transformation of gonocytes to spermatogonia occurred at 150 days of age. The formation of primary spermatocytes, spermatid and spermatozoa cocurred at the age of 150 days, 300 days and 300-360 days, respectively. The process of transformation of supporting cells was initiated at 120 days and completed at 180 days of age. The transformation of immature Leydig cells to mature cells was initiated at 150 days and completed, by 180 days of age. There were distinct regional differences between the caput, the corpus and the cauda epididymis in respect of the diameter of the tubules, height of the epithelium and the degree of transformation of Epithelial lining from simple columnar to pseudostratified type. The distal part of the ductus epididymis seemed to have attained the adult size at an earlier age than the proximal. Sperms were seen in all the three regions at about 300 days. The mean values of ejaculate volume, initial motility, sperm concentration, live sperm count, sperm head abnormalities, tail abnormalities and proximal protoplasmic droplets were found to be 2.65 ± 0.84 ml, 66.24 ± 0.87%, 1599.64 ± 55.371 milions per ml of semen, 72.55 ± 1.310%, 4.91 ± 0.439%, 0.65 ± 0.045%, 6.47 ± 0.775% and 1.20 ± 0.143%, respectively. Significant (p<0.01) variations between bulls were observed in respect of sperm head abnormalities, tail abnormalities and proximal protoplasmic droplets and between months, in respect of ejaculate volume, sperm head abnormalities, free loose head, tail abnormalities and proximal protoplasmic droplets. Seasonal variation (p<0.05), however, was evident only in the incidence of tail abnormalities. Variations due to age of bulls were found to be significant (p<0.01) in the casse of ejaculate volume, sperm concentration, free loose head, middle piece abnormalities and tail abnormalities. The freezability of sperms expressed in terms of per cent of post-thawing motility was found to be 36.86. There was no seasonal effect on the freezability of sperms. The freezability rate increased significantly (p<0.01) with advancement of age of bulls. The overall rejection rate of the ejaculates was noted to be 39.80%. Most of the rejection (71.75%) was done before freezing. The pre-freezing rejection was found to be 28.55% of the total ejaculate. The post-freezing discard to be 15.74% of the frozen samples. The rejection rates of the ejaculates differed significantly (p<0.01) between months/seasons/age of the bulls. The rate of rejection was found to decrease with advancing age. The overall fertility rate of the bulls was found to be 56.06%. There were significant (p<0.01) differences in the fertility rate between months/seasons of insemination and between age of the bulls. As between bulls also, there was a significant variation (p<0.01) in the fertility rate. The significance of the observations inferences indicated above and their relevance to the implementation of cross breeding programme in Kerala were discussed briefly.ThesisItem Open Access Studies on the biology, pathogenicity and treatment of important nematodes of domestic duck(Department of Parasitology, College of Veterinary and Animal Sciences,Mannuthy, 1977) Chandrasekharan, K; KAU; Kalyanasundaram, RStudies on the incidence of nematode infections in 340 domestic ducks indicated that 67.94% of birds harboured one or more species of the following nematodes viz., Amidostomum globocaudata skrjabini , capillaria contorta, capillaria , Echinuria uncinate, Epomidiostum uncinatum, Eustrongylides papilosus, Strongyloides avium and tetramers antis. The rate of infection was highest in the case of Epomidiostomum uncinatum (41.86% ) and lowest in the case of strongyloides avium (0.59%). The lifecycles of Echinuria uncinata and Tetramers anatis were worked out in detail. It was established that Tetramers anatis was distinct from Tetramers Fissispina. The complete details of the morphology of juveniles both within the intermediate and final hosts were given. The juveniles of Echinuria uncinata completed the first and second moultings on the third and fifth day respectively and the stage juveiles reached infective stage on the seventh day following infection in Daphnia pulex at a room temperature ranging from 25 to 30C0. In ducklings the juveniles underwent the third and fourth moultings on the third and seventh day respectively and the eggs of the parasite were first found in the droppings on the thirty- third day. The juveniles of Tetramers anatis completed first mopulting on the third day, the second moulting on the fifth day and the third stage encysted in fat bodies of the grasshopper, Spathosternum prasiniferum. The third stage juveniles attained infective stage on the sixth day following infection. Within the ducklings, the parasite underwent the third moulting on the third day. The fourth moulting in respect of males was seen on the nineth day and in the case of females on the tenth day. The prepatent period of the parasite was found to be 24 days. Development of the juveniles was also noticed in five other species of grasshoppers viz., Oxya nitidula, Oedaleus abruptus, Conocephalus maculatus, Ducetia Japonica and Atractomorpha crenulata. No development of Tetrameres anatis, beyound the first stage was observed inDaphnia Pulex and Daphnia Magna on experimental infection. Anaemic changes with significant reduction in weight gain and haematological values were observed in experimental infections of Tetrameres anatis, Amidostomum skrjabini and Epomidiostomum uncinatum. Histopathological changes like haemorrahage, desquamation of cells, catarrbal inflammation and necrosis were seen in experimental tetramerosis. Ulceration and atrophy were also evident in amidostomiasis and epomidiostomiasis. The anthelmintic efficacy of 9 drugs against adult worms of Tetrameres anatis, Amidostomum skrjabini and Epomidiostomum uncinatum under experimental infections were determined. The efficacies against tetramerosis, amidostomiasis and epomidiostomiasis were 79.23%,32.15% and 79.88% with Tetramisole by drochloride at 50 mg/kg body weight; 70.36%, 52.42% and 50.23% with phenothiazine at 500 mg/kg; 26.85%, 74.8% and 65.68% with Morantel tartrate at 40mg/kg; 45.70% 67.29% and 57.84% with Parbendazole at 100 mg/kg; 41,0%’63/93% and 43.13% with Thiabendazole at 200 mg/kg; 59.28%,61.06% and 52.66% with Carbontetrachloride at 2ml/kg; 35.94%, 30,12% and 13.13% with Methyridine at 200 mg/kg; 28.87% 20.17% and 11.32% with Disophenol at 10 mg/kg and 31.02%, 39.04% and 12.66% with Cashewnut shell oil at 10 g/kg body weight respeectively. The drug Rametin at 200 mg/kg was found to be fatal to ducklings. In a cross infection trial delyed development and lesser percentage of establishement of Ascaridia galli of fowl origin were observed in ducklings as compared to chicks.ThesisItem Open Access Studies on the common ticks affecting live-stock in Kerala(Department of parasitology, College of Veterinary and Animal Sciences, Mannuthy, 1980) Rajamohan, K; KAU; Kalyanasundaram, RAn investigation was conducted for a period of 5 years from 1974 to 1979 in to the incidence of ticks on domestic animals in Kerala, the biology of the most common species, and their susceptibility to four commonly available organo phosphorus compounds.. Nine different species of ticks belonging to 5 genera were collected from cattle, buffaloes, goats and dogs in different localities of the eleven districts of Kerala. The species of ticks identified were boophilus annulatus, rhipicephalus sanguineus, R.haemaphusaloides, R.turanicus, haemaphysalis bispinosa, H. turturis, H.spinigera, Hyalomma anatolicum and Amblyomma integrum. The commonest among them was boophilus annulatus, which was found mainly on cattle. The incidence of this tick was very high in the hilly areas and in the western ghat regions. The other common ticks found on cattle were Rhipicephalus haemaphysaloides and Haemaphysalis bispinosa. Tick infestation was found to be rare in buffaloes and goats and the common species found on them were Haemaphysalis bispinosa and B. annulatus. IN dogs the species recorded in the present study were Rhipicephalus sanguienus and R. turanicus. Variations in incidence was evidenced from the present study. The maximum incidence was found in the months of July, August, September, October and November. The life-cycle of B.annulatus was completed experimentally in a period 44 days. The maximum number of eggs produced by one tick was 1420 and minimum 680. The incubation period was dependent on the room temperature and variation in humidity had little influence. The larvae were found to prefer hairy areas of the body for attachment, and they did not attach at the hairless and exposed areas. The engorged females were found to drop off quickly when green grass was spread on the floor of the experimental animal’s shed. The life-cycle patter could be summarised as: Pre-oviposition : 1 to 6 days Oviposition : 5 to 9 days Incubation period : 16 to 30 days Larval fasting : 2 to 5 days Larval feeding : 4 to 7 days Larval moulting : 8th to 12th day of infection Nymphal feeding : 3 to 6 days Moulting of Nymph : 15 to 19th day of infection Adult feeding : 5 to 10 days Detatchment of female : From 20th day of infection onwards Four organophosphorous compounds viz. Malathion, Fenitrothion, Dichlorvos and Phosalone were tested for their action on ticks. The ovicidal and larvicidal actions and the lethal effects on nymphas and engorged females of B. annulatus, R sanguinius and H. bispinosa were studied in the laboratory. Cythion (malathion 50%) 0.5 to 1%, Sumithion (Fenitrothion 50 %) 0.5 to 1%, Dichlorvos (Nuvan) 0.1 to 0.2%, and Zolone (Phosalone 35 %) 0.2 to 0.3% were found effective at different degrees. The efficacy was directly proportional to the concentration of compound and the duration of treatment. Phosalone showed maximum efficacy followed by Dichlorvos. In field trials, all the four compounds gave satisfactory results. But phosalone showed maximum efficacy and least toxicity to animals. Nuvan was also effective but was the most toxic among the four compounds. Thus the acaricide of choice for routine use in Kerala was determined to be Phosalone (35%) at a concentration of 0.3% to be used as a spray or wash.
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