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  • ThesisItemOpen Access
    Biology of neoplastic cells of ethmoid carcinoma
    (Department of Pathology, College of Veterinary and Animal Sciences, Mannuthy, 1985) Madan Sing, Karki; KAU; Rajan, A
    Attempts were made to propagate the ethmoid carcinoma cells in vitro to study the biological behaviour of the neoplastic cells and their relationship with the host. Efforts were also made to transplant the neoplastic cells in laboratory animals and tumour bearing natural hosts so as to lay out a model system for further investigation. In vitro propagation was tried by obtaining the tumour tissues from nine cows and three goats. Cells were grown in Hank’s balanced salt solution (HBSS). TC – 199 and Dulbecco’s modified Eagle’s medium with 10 to 20 per cent calf serum. The cell suspension was seeded into tissue culture bottles, milk diluting bottles and test tubes and incubated at 370 C. No growth was observed in the cultures made from the tumour tissue of cows. The tumour cells from two goats grew in monolyerand were maintained for nine days. There was no difference in growth of cells in different media employed. Insulin supplementation in the media did not cause any difference in the growth of the cells. Subsequently the cells died even after subculturing and changing of the media. Absence of certain unknown factors required by the neoplastic cells for growth was considered responsible for failure of the growth. Transplantation studies were carried out in autologous, homologous and heterologous species of animals using the tumour tissue framgments, homogenate, filtrate and cell suspension. No autograft or heterotransplant were successful. Homologous transplantation resulted in a firm painless growth at the site of injection. The growth initiated a cell – mediated immune response at the site of implantation. Failure of neoplastic cells to grow in the other hosts was considered to be due to rejection of the transplants by the host’s immune system.
  • ThesisItemOpen Access
    Pathology of hypothyroidism in pigs
    (Centre of Excellence in Pathology, College of Veterinary and Animal Sciences,Mannuthy, 1995) Prasanna, K S; KAU; Sreekumaran, T
    An experimental model of hypothyroid state was induced in piglets, using thiourea with the objectives of studying the sequence of clinico pathological changes and its influence on the animal health and growth. Tweleve Large White Yorkshire male piglets of 2 – 3 months age were selected for the study. The animals were divided into control group of six animals and experimental group of six animals. Experimental hypothyroidism was induced by feeding thiourea daily for a period of three months at the dose level of 50 mg per kg body weight. Haemogram, body weight, plasma proteins, serum cholesterol and serum thyroxine values were estimated at periodic intervals. The piglets were subjected to detailed autopsy after sacrifice. Gross lesions were recorded and detailed histopathological examination of tissues was carried out. During the course of experiment all the experimental animals recorded stunted growth and appreciable reduction in feed intake and alopecia of neck and shoulder regions. There was significant increase in blood cholesterol values and plasma protein level in thiourea fed group. A significant reduction in serum thyroxine level was also recorded. There was significant increase in the relative weight of thyroid, adrenal and pituitary glands of experimental animals. Gelatinisation of subcutaneous fat and dilatation of right ventricles were common findings at autopsy. Histologically the thyroid glands exhibited varying degree of hyperplastic changes and depletion of colloid in the follicles. Hyperplasia and hypertrophy of the lining epithelium was also observed. Predominant histological changes in the pituitary was hyperplasia and hypertrophy of the basophil cells and degranulation of the acidophil cells. Adrenal glands showed diffuse hyperplasia of zonafasiculata and accessory cortical nodule formation. Skin revealed acanthosis, hyperkeratosis and keratinisation of harifollicles. In all the hypothyroid animals testis showed varying degree of tubular degeneration. A random survey study was conducted to assess the thyroid status of pigs from different parts of Kerala using serum thyroxine as the marker. This concluded that most of the animals had the normal range of serum thyroxine levels.
  • ThesisItemOpen Access
    Determination Of Permissible Level Of Aflatoxin In Broiler Chicken Feed
    (Department of Pathology, College of Veterinary and Animal Sciences,Mannuthy, 1999) Arulmozhi A; KAU; Koshy Varghese
    The study was undertaken to assess the effect of various levels of aflatoxin on the performance of broilers and to establish the permissible level of aflatoxin in the broiler feed. One hundred and eighty day old broiler chicks were divided into six groups of 30 birds each and were given feed containing graded levels of aflatoxin at 0, 20, 40, 60, 80 and 100 ppb for a period of 45 days. Feed intake, weekly body weight gain, feed efficiency, haemogram, serum profile, organ weight, residual aflatoxin in tissues and pathological changes in liver, kidney, bursa and spleen were studied at fortnightly intervals to evaluate its dose related effects. A dose dependent decrease in the daily feed intake and mean body weights were noticed in all the groups. The cumulative FeR was extremely poor at 80 and 100 ppb levels at sixth week of age. The toxicopathological changes in the birds varied in its intensity in relation with the level of aflatoxin in the feed, with most severe changes being at higher dose levels. The values of haemoglobin, PCV, total leucocyte count, Iymphocytes, total serum protein and albumin showed a decrease whereas the ESR, heterophil and serum enzyme were increased. The aflatoxin, even at 20 ppb levels caused degenerative and necrotic changes in liver and kidneys and the intensity of the lesions increased with higher levels of toxin. Attempt for regeneration and repair processes were well pronounced by the 30th and 45th day. Lymphoid depletion was a characteristic feature in bursa and spleen. Degeneration and lysis of lymphocytes with cys; formation was also seen in bursal follicles. Residual aflatoxin was detected in the liver and muscle in all groups by the 45th day. The net returns from the toxin treated birds showed a dose related decline compared to control and the loss in profit at 20 ppb level was marginal About 24 per cent of the poultry feed samples tested during the period from January to July 1999 were contaminated with aflatoxin quantitatively ranging from 20 to 200 ppb. The results of the present study shows that even at 20 ppb aflatoxin causes cellular and subcellular damage to the tissues. However, the economic loss at this level was marginal when compared to higher dose levels. Hence 20 ppb can be considered as permissible level in broiler chicken feed.
  • ThesisItemOpen Access
    Immunopathologic and toxic effects of endosulfan in chick embryo
    (Centre of Excellence in Pathology, College of Veterinary and Animal Sciences, Mannuthy, 2004) Kalai Selvan, P; KAU; Divakaran Nair, N
    The present study was undertaken to investigate the immunopathologic and toxic effects of endosulfan in chick embryo. The embryos were exposed to endosulfan at various dose levels through different routes. The weight of the embryo, bursa, thymus and spleen, histopathology of the lymphoid organs, liver, kidney and brain and quantification of the preformed maternal IgY level in the egg yolk were the parameters analysed to study the effects. Endosulfan was found to be teratogenic at the grven dose levels. The abnormalities observed were agenesis of beak, crossed beak, short lower beak, eventration of viscera and curled toe. Endosulfan did not cause any significant gross changes in the developing embryos except mild haemorrhages. Endosulfan treatment did not produce any significant reduction in the weight of the embryos as well as the weight of the lymphoid organs. On histopathological examinations endosulfan was found to be nephrotoxic and hepatotoxic to the embryos. Varying degrees of degeneration and necrosis was evident in kidney and liver. Effect on the bursa, thymus and spleen were mild to moderate where in the degenerative changes predominated. Dose dependent increase in the involution process of the thymus as evidenced by increase in the Hassal's zone was observed. The lesions in the developing lymphoid organs reflected that endosulfan is toxic to the system and going to affect the immunocompetency by way of immunosuppression and thereby rendering the chicks susceptible to various diseases. The study indicated that the endosulfan treatment did not have any effect on the preformed maternal immunoglobulin level in the egg yolk.
  • ThesisItemOpen Access
    Pathology of cardio-pulmonary disorders in canines
    (Centre of Excellence in Pathology, College of Veterinary and Animal Sciences, Mannuthy, 2003) Pradeep, M; KAU; Vijayan, N
    The present study was undertaken to assess the prevalence and pathology of various cardiac and pulmonary disorders in dogs. The data collected from the autopsy records maintained at the Centre of Excellence in Pathology, Mannuthy and seventy eight samples of heart and lungs from necropsy cases formed the basis of the study. Ninety nine per cent cases showed varying types of cardiac and pulmonary lesions. The highest incidence in the heart was dilated (75.32 per cent) and hypertrophic (15.58 per cent) cardiomyopathies. The other lesions found were hydropericardium, cardiac tamponade, haemorrhage, myocarditis, endocarditis, endocardial fibroelastosis, valvular blood cyst coronary arteriosclerosis and mural. thrombus. Myocardial infarction was found to be confined to the left ventricles and interventricular septum in all the encountered cases (5.19 per cent). Pulmonary congestion (70.51 per cent), haemorrhage (32.47 per cent) and edema (31.17 per cent) were observed with higher incidence rate. The other lesions found in the lungs were bronchitis, emphysema, pneumonia, collapse, infarction, mineralization, ossification, anthracosis and endarteritis obliterans. Metastatic osteosarcoma in the lungs, metastatic lymphosarcoma in the heart and lungs were also observed. The incidence of cardio-pulmonary disorders encountered was relatively high. The need and scope for investigation into the pathological disorders of the heart and lungs of canines were highlighted.
  • ThesisItemOpen Access
    Gastrointestinal and neurotoxic effects of cypermethrin in rats
    (Centre For Excellence In Pathology, College of Veterinary and Animal Sciences, Mannuthy, 2008) Remya Nair, R; KAU
    The present study entitled ‘Gastrointestinal and neurotoxic effects of cypermethrin in rats’ was undertaken to investigate the potential toxic effects of cypermethrin in rats with particular emphasis on its effect on the nervous and digestive system.The clinical signs, gross pathology, histopathology, haematology and biochemical parameters were analysed to study the effects. Cypermethrin was found to be neurotoxic and gastroenterotoxic at the given dose levels. Oral administration of cypermethrin in medium and high doses produced nervous signs in animals. However cypermethrin did not cause any significant variation in the body weight of animals. All haematological parameters evaluated showed a dose dependent reduction in its value. Biochemical parameters assessed revealed hepatotoxic and multisystemic effects of cypermethrin. Gross lesions observed in the intoxicated groups were bloat, congestion of lungs, heart, brain, pulmonary haemorrhage and degenerative changes in liver and kidneys. On histopathological examination, cypermethrin was found to be neurotoxic, hepatotoxic, enterotoxic, pneumotoxic, cardiotoxic and nephrotoxic as evidenced by varying degrees of degeneration and necrosis in various organs examined. Effects on all organs were mild to moderate degenerative changes at the low dose level. Medium and high dose intoxicated groups revealed necrotic changes, extensive haemorrhages, congestion in organs like liver, kidney and lungs apart from the changes observed in low dose group animals. Haemodynamic disturbances were manifested in the forms of congestion and haemorhages in lungs, heart, liver and kidneys. The histopathological evaluation revealed no cypermethrin induced toxic effects on the oesophagus. Spinal cord lesions were observed only in the lowest dose group. Brain lesions were only degenerative changes. These findings suggested that biochemical effects rather than structural changes were involved in toxicity.
  • ThesisItemOpen Access
    Pathology of the reproductive system in ducks
    (Department of Pathology, College of Veterinary and Animal Sciences, Mannuthy, 1986) Jayakumar, P M; KAU; Valsala, K V
    A study was conducted on the pathology of the reproductive system in ducks. A survey conducted on the prevalence of diseases based on the data for a period of 11 years at the Government Duck Farm, Niranam revealed the incidence of hepatosis (64.58%), hepatitis (9.07%), enteritis (8.58%), tuberculosis (2.61%) and miscellaneous disorders (15.13%). The latter category included pulmonary edema, omphalitis and transport stress. In a separate study, the reproductive organs of 194 female ducks and 26 male ducks were examined systematically and gross and histopathological lesions encountered were studied. The diseases encountered in females were hypoplasia of left ovary and oviduct (20%), impaction of oviduct (5.45%), haemorrhagic cyst in the ovary (7.27%), salpingoperitonitis (10.9%), oophoritis (49.09%), cystic right oviduct (1.82%), mycotic salpingitis (1.82%) and tuberculous salpingitis (3.63%). In males atrophic testis (66.3%) and seminoma (33.3%) were the diseases recorded. Experimentally, pure aflatoxin B1 and ochratoxin A were administered to six ducks each, at the rate of 25 µg per duck daily for a period of three months. Clinically all the experimental ducks showed unthriftiness. But it was more pronounced in aflatoxin group. In both aflatoxin and ochratoxin group, the birds showed reduced weight gain and decreased feed intake. There was reduction in the weight of the testis in both aflatoxin and ochratoxin groups. Histologically, in the aflatoxin group, marked disruption in the organisation of germinal epithelium, absence of sperm bundles and edema of the interstitial tissue were the lesions observed. In the ochratoxin group, the basement membrane was found to be unaffected. Both aflatoxin and ochratoxin were found to cause degenerative changes in the testicular tissue. However, aflatoxin was found to cause more pronounced changes than ochratoxin. From the studies made, it was concluded that both aflatoxin and ochratoxin can induce degenerative changes in the testis and it was surmised that this would lead to subfertility and infertility. The need for feeding a diet free of mycotoxins to ensure profitable duck farming was stressed.
  • ThesisItemOpen Access
    Studies on pathological conditions in the mammary glands of cattle and goats
    (Department of Pathology, College of Veterinary and Animal Sciences, Mannuthy, 1976) Lalitha Kunjamma, C R; KAU; Krishnan Nair, M
    An investigation was carried out to study the pathological lesions encountered in the mammary glands of cattle and goats from specimens selected from slaughter house and autopsy cases. The somatic cell count in milk from clinical and sub – clinical cases of mastitis was also undertaken. Two hundred quarters from cows and 67 halves from goats were subjected to detailed histopathological investigation. Mastitis was found to be the important type of lesion encountered. Lesions varied from subtle changes to intensive involvement with complete obliteration and atrophy. The lesions encountered were catarrhal mastitis and galactophoritis, suppurative mastitis, acute diffuse mastitis, necrotising mastitis, gangrenous mastitis, interstitial mastitis and tuber - culous mastitis. Other significant alternations associated with or without mastitis were congestion and oedema, squamous metaplasia of lining epithelium of ducts and cisterns and calcification of vessel walls. The calcification of the vessels was similar to that observed in ‘Monckeberg’s sclerosis’ in human beings. No tumours were found. It was suggested that lymphoid cells found in the interstitial septa of the mammary glands of goats affected with John’s disease might be the ‘T’ type of lymphocytes which are concerned with cellular immunity. The cystic changes encountered in the glands were not considered as the separate entity – Fibrocystic disease – but only compensatory processes as a result of fibrosis and atrophy of some part of the glandular and ductal system. Micro concretions were constantly observed and it was suggested that calcium got deposited over inspissated and hyalinised milk proteins. A total of 189 quarter samples of milk was also examined for total somatic cell count, differential count and by culturally for the presence of pathogenic bacteria and fungi. The total cell count in normal milk of cows and goats varied from 150,000 to 500,000 per ml. In sub – clinical and clinical cases upto 30,000,000 cells per ml could be counted. The percentage of neutrophils in normal milk was below 31% in goats and 43% in cows. The corresponding maximum values in mastitic cases were 88% and 92% respectively. In both cows and goats the chief etiological agent for mastitis as found in the present study was Staphylococcus. Other organisms encountered were Strephylococcus, Coliforms and Corynebacteria.
  • ThesisItemOpen Access
    Pathology of the eye in cattle bearing carcinoma of the mucosa of the ethmoid
    (Department of Pathology, College of Veterinary and Animal Sciences, Mannuthy, 1982) Jose, C J; KAU; Ramachandran, K M
    Eighteen cattle from different parts of Kerala, affected with ethmoid carcinoma were subjected to detailed investigations of the ocular changes. The incidence of eye involvement in cases of ethmoid tumour in cattle was assessed on the basis of reports or informations received from field veterinarians and cattle owners from different dietricts of Kerala. Incidence, clinical manifestations, intraocular pressure, gross pathological cbanges and biometry of the eye were studied. The effect of the tumour mass on the eye and the possible causes for the different ocular changes has been discussed. The highest incidence was found in the age group of six to ten years. The earliest case was recorded in a heifer aged four years. The frequency of the incidence was high in females (88%). Crossbred animals were found to be more affected (83%). The tumour was also encounter~d in three purebred cattle. Ninetyfour percent of the tumour affected animals showed exophthalmos either unilateral (82%) or bilateral (18%). Tbe left eye was affected in 14 percent and the right eye in 86 percent cases. It is suggested that 37 exophthalmos can be considered as a pathognomonic clinical manifestation for ethmoid tumour affected cattle. Blindness was observed in 90 percent of the affected eyes, ectropion in 85 percent cases and corneal cbanges in the form of keratitis or opaCities in 90 percent cases. Episcleritis, anterior uveitis, euphora, purulent discharges were the other clinical manifestations. Glauc~a, was found to be a characteristic feature in ethmoid caroinoma. Involvement of the optic nerve, optic diso, retina, vitreous and other deep structures of the eyes were also notioed by gross examination of the whole eye at autopsy. The lens showed varying degrees of displacement or luxation.