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Theses

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1998 - 199952000 - 201026
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Subject: Veterinary Pathology × Author: KAU × Start date: 1997 ×
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Now showing 1 - 9 of 31
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    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.
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    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.
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    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.
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    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.
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    ThesisItemOpen Access
    Hepato-renal pathology in canines
    (Centre of Excellence in Pathology, College of Veterinary and Animal Sciences, Mannuthy, 2001) Lakshmi, R; KAU; Koshy Varghese
    The present investigation was undertaken to assess the prevalence and pathology of the liver and kidney disorders in canines. The results of the present investigation and the evaluation of data from the records revealed a high incidence of liver (76 percent) and kidney (85 per cent) disorders. A detailed systematic examination of one.hundred cases of canine carcasses brought for autopsy during the period of investigation was conducted and the gross and histopathological lesions were studied in detail and were classified based on age, sex and breed. Vascular and degenerative changes were the predominant lesions in these organs. The other lesions recorded in the liver were necrosis (15 cases), hepatitis (19 cases), fibrosis (9 cases) and cirrhosis (2 cases). One case each of cholangiocarcinoma, hepatic cyst and adhesion of diaphragm and the liver was encountered in the present study. Among kidney disorders, glomerular lesions were predominant next to vascular and degenerative changes. A total of 59 cases had some lesions in the glomeruli of which, 32 hadglomerulonephritis. PGN was the predominant type of glomerulonephritis. Males had a higher predilection for PGN and it was common in animals less than three years of age. MN and MPGN were common in animals more than three years of age. The high incidence of glomerular lesions and their possible causes were discussed. Tubulo-interstitial nephritis was observed in 16 cases. Interstitial nephritis was common in males while both cases of pyelonephritis were seen in females. Acute interstitial nephritis was seen in animals less than five years of age while all cases of chronic interstitial nephritis was seen in animals more than five years of age. Bacterial isolations were obtained in the liver or kidney or both in only 14 cases. Viral etiology was suspected in two cases where intranuclear inclusions were seen in the hepatocytes and the glomerular epithelium. The high incidence of vascular lesions without any evidence for infectious etiology in rest of the animals suggested the involvement of some toxic factors. The importance of identifying the specific etiology in these suspected cases of toxic conditions and the need and scope for further studies in these lines were highlighted.
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    ThesisItemOpen Access
    Immunopathological response of the duck (Anas platyrrhyncos domesticus) to sublethal dose of selected agro-chemicals
    (Centre of Excellence in Pathology, College of Veterinary and Animal Sciences, Mannuthy, 1998) Vijayan, N; KAU; Valsala, K V
    The study was conducted with the objective of assessing the teratologic, embryotoxic and immunopathologic effects of two agro-chemicals carbofuran and 2,4-D used in agricultural operations, on duck embryos and ducklings. The embryological studies included the observation on the embryonic defects and weight of the lymphoid organs along with the histopathologic and ultrastructural studies of the lymphoid organs like the bursa, spleen and thymus. The results showed that the contamination of the eggs with the above chemicals caused moderate deleterious effects on the lymphoid system, though no teratologic effects could be observed. The histological and ultrastructural changes also confirmed the deleterious effects at the tissue and cellular level. The immune system of the ducks exposed to the above chemicals for two different durations were assessed using a battery of tests. The humoral immune system was assessed based on the body weight, lymphoid organ weight, haematological evaluation, serum biochemical evaluation and the evaluation of HI titre against NDV. The cell-mediated immune system was assessed by the skin reactivity tests to DNCB and PHA. LMIT and GVHR were also employed to assess the cell-mediated immune system. The histological and ultrastructural studies were also conducted after six weeks and ten weeks of the experiment. The assessment of the immunological profile employing these elegant tests revealed that these agro-chemicals caused mild but significant suppression of the cell-mediated and humoral immune response. By this investigation it was clarified that these agro-chemicals have mild to moderate degree of immunotoxic effect when exposed for a short duration, but the changes were severe when exposed for longer duration. From the .studies, it was demonstrated that the immunotoxic effect of carbofuran is more compared to 2,4-D (herbicide) and the changes were dose and time dependent.
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    ThesisItemOpen Access
    Pathology of the reproductive system of Japanese Quails (Coturnix coturnix japonica)
    (Centre of Excellence in Pathology, College of Veterinary and Animal Sciences, Mannuthy, 2003) Sivakumar, V; KAU; Mammem, J Abraham
    The present study was undertaken to assess the prevalence and pathology of various diseases affecting the reproductive system of Japanese quails. The data collected from the autopsy records maintained at the Centre of Excellence in Pathology, Mannuthy and one hundred and two samples of reproductive organs obtained from the necropsy cases formed the basis of the study. Retrospective survey revealed the increasing incidence of the reproductive diseases. Out of the 1139 cases encountered, various reproductive diseases were seen in quails at an incidence rate of 25.11 per cent. Oophoritis was the most prevalent among them at an incidence rate of 9.46 per cent. The higher incidence of reproductive diseases could be attributed to the maintenance of large number of breeder stock in the quail farm, which formed the major source for the necropsy samples. The gross and histopathological examination revealed that among the reproductive diseases the highest mortality was due to oophoritis (12.64 per cent) followed by egg bound (11.75 per cent). Other cases were salpingitis, egg impaction, ovarian fibroma, testicular hypoplasia and orchitis. Escherichia coli, Klebsiella and Proteus were isolated from various cases. The incidence of pathological disorders encountered was relatively high. The need and scope for investigation into the diseases affecting quail reproductive system were highlighted.
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    ThesisItemOpen Access
    Utero-ovarian and endocrine pathology in goats
    (Centre for Excellence in Pathology, College of Veterinary and Animal Sciences, Mannuthy, 2008) Thomas, K Thomas; KAU; Vijayan, N
    The present study was aimed at finding out the various utero ovarian disorders affecting goats and correlating with the lesions of pituitary, thyroid and adrenal glands. A total number of 1000 genital tracts were examined for utero-ovarian disorders. Out of which 84 genitalia showed one or more lesions in the ovary, oviduct and uterus. A total of 54 cases out of 84 showed lesions in the ovaries. The follicular cysts were the most common condition and were recorded in 14 cases (1.4%). The other conditions encountered were ovarian hypoplasia (0.6%), luteal cyst (0.3 %), embedded corpus luteum (0.3 %), persistent corpus luteum (0.2 %), ovarian haematoma (0.2 %), ovarian sclerosis(0.4 %), senile atrophy (0.3 %), follicular atresia (0.4 %), epoophoron (0.2 %), serous inclusion cyst (0.2 %), parovarian cyst (0.6 %) and perioophoritis (0.3 %). Seven cases showed lesions in the oviduct. The conditions encountered were hydrosalpinx (0.2 %), hyperplasia of the salpingeal epithelium (0.2 %) and ovario-bursal adhesion (0.3%).Uterine disorders were recorded in 36 cases. The conditions encountered were cystic endometrial hyperplasia (0.6%), adenomyosis (0.4 %), mucometra (0.4 %), perimetrial cyst (0.6%), endometritis (1.4 %) and metritis (0.2%). The histopathological changes of all these conditions have been studied in detail and the possible pathogenesis described. The various pathological changes associated with reproductive disorders are suggestive of endocrine imbalances, multiple nutritional deficiencies, infectious nature, managemental factors and developmental defects. The results of the study highlighted the need to monitor the hormonal levels in the blood, micronutrients and managemental factors. Lesions of varying frequency in pituitary, thyroid and adrenal glands were recorded in 23 out of 84 cases with utero-ovarian lesions examined. Lesions observed in the pituitary glands were pituitary abscess (1), Pituitary cyst (6) and pituitary apoplexy (2). In the thyroid gland, lesions recorded were hypoplasia (7), colloid goitre (5) and nodular goitre (2). Lesions observed in the adrenal glands were cortical hypoplasia (2), cortical hyperplasia (5) and medullary hyperplasia (8). Correlation study has highlighted that in many of the utero-ovarian disorders there were concurrent affections of the endocrine glands particularly pituitary, adrenal and thyroid glands which is of major significance.
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    ThesisItemOpen Access
    Pathology of pneumo-enteric lesions in goats
    (Centre for Excellence in Pathology, College of Veterinary and Animal Sciences, Mannuthy, 2007) Hamza, Palekkodan; KAU; Vijayan, N
    The present study was undertaken to assess the mortality pattern, prevalence and pathology of pulmonary and intestinal tract disorders in goat. The result of the present investigation and evaluation of data from the records revealed a high incidence of pulmonary and intestinal tract disorders in goat. A total of 111 cases were subjected to detailed investigation which included 80 kids, 11 young ones and 20 adults. The samples collected were subjected to detailed gross and histopathological examination. The lesions observed were classified and recorded and the lesions were explicated giving possible etiopathogenesis. The study revealed eighty percentage incidence of pulmonary lesion. The pulmonary lesions observed were congestion, oedema, atelectasis, emphysema, pneumonia and pulmonary haemorrhage. The pneumonic lesions encountered were classified as suppurative pneumonia, fibrinous pneumonia, interstitial pneumonia, haemorrhagic pneumonia and aspiration pneumonia. The gross and histopathological features of each type of pneumonia have been described and possible etiological factors had been indicated. Escherichia coli, klebsiella sp. and Corynebacterium sp. were isolated from the pneumonic lungs. The lesions observed in bronchial lymph nodes were congestion, oedema, depletion of lymphocytes and necrotic changes in the cortical area. Bronchi and bronchioles revealed proliferative and inflammatory lesions suggesting a viral etiology with secondary bacterial infection or exposure to chronic air pollutant which act as irritant. Seventy two per cent of cases showed various pathological lesions in intestinal tract. The major lesions encountered in small intestine were congestion, degeneration and necrosis, catarrhal enteritis, subacute enteritis, haemorrhagic enteritis and ulceration. The parasitic lesions observed in intestinal tract were coccidiosis, pimply gut and cestodiasis. Lesions in the large intestine were congestion, degeneration and necrosis, catarrhal colitis and necrotic colitis. Mesenteric lymph node changes included oedema, congestion, degenerative and necrotic changes. Escherichia coli and Klebsiella sp. could be isolated from intestinal contents and the possible role of these organisms in the causation of enteritis had been discussed. An attempt was made to correlate the lesions in respiratory and intestinal tract. Even though there were no typical gross lesions suggesting PPR, the possibility cannot be ruled out without using modern techniques such as immuno histochemical studies.