خلاصة اطروحتي للماجستير مع بعض صور المناقشة

تقييم مصلي و نسيجي لبعض اللّقاحات التجارية المتوفرة لمرض التهاب جراب فابريشيا المعدي في دجاج أللحم

Summary

This study was designated to evaluate eight commercial live vaccines against infectious bursal disease. Four hundred and sixty, 1-day-old ROSS broiler chicks divided randomly into 9 groups. Each group consist of 50 birds, groups 1, 2, 3 and 4, were vaccinated with an intermediate vaccines, whereas groups 5, 6, 7 and 8 were vaccinated with an intermediate plus vaccines. The vaccines were given by intracrop route at 14 days of age. The last one was acted as control unvaccinated group.
Different parameters were used to evaluate these vaccines including; clinical signs and gross lesions following vaccination, indirect ELISA test, lymphoid organs (bursa of Fabricius, spleen, and thymus) to body weight index, histopathological examination of bursa, spleen, and thymus as well as measurement of post vaccination stress by measuring of corticosterone hormone by using competitive ELISA test.
Blood samples were collected at the 1st days of old for detection of maternal derived antibody (MDA), whereas blood samples has been collected from all groups at 21st, 28th and 35th day of life post vaccination for detection IBD antibody titer while blood samples were collected at 24hrs, 48 hrs and 72 hrs. post vaccination for detection of corticosterone hormone. Bursa, spleen and thymus were removed at 17th and 28th days of age to estimated organ index and histopathological changes.
The results did not reveal any clinical signs or mortality in all groups throughout the experiment. Gross lesions were observed in the chicks of vaccinated groups after 3 days post vaccination during the experiment in four birds of group 5, and five birds of group 8 that included swollen bursa and kidneys that filled with white urate deposits.
The result of the bursal index showed that birds from group 4, 5, 7 and 8 had significant increase (P<0.05) in BI at 17th day of age. Whereas groups 8, 5 and 4 had significant reduction (P<0.05) in BI at 28th days of age which indicated bursal atrophy as compared with control and other vaccinated groups.
Spleen index revealed that significant reduction of spleen index (P<0.05)which was noted in group 4 ,5 and 8 at 28th days of age as compared with control and other vaccinated groups throughout the experiment.
Thymus index indicated that significant reduction (P<0.05) in group1, 5 and 8 at 28th days of chickens age as compared with control and other vaccinated groups. Group1, which was vaccinated with intermediate vaccines.
Histological examination of bursa of Fabricius, spleen and thymus revealed that all type of vaccines induced different degree of alterations in these organs. The organs of birds in group1, 2, and 4, which were vaccinated with intermediate vaccines showed similar degree of changes which characterized by an edema and degeneration in the medullary area of bursal follicles were observed in bursa. Spleen from group1 and 2 showed follicular necrosis and sinusoidal congestion, whereas spleen section obtained from group 4 showed hydropic degeneration in the epithelial layer. Thymus section obtained from group1, 2, 4 represented by congestion and hemorrhage in the medulla with lymphocytic depletion. Bursa from group 3 showed thickened capsule. Spleen section showed hydropic degeneration in the epithelial layer of the blood vessels, whereas the thymus changes represented by focal area of hemorrhage. Whereas groups 6 and 7, which were vaccinated with intermediate plus vaccines, exhibited similar histopathological changes in bursa of Fabricious which represented by an edema, and fibrosis. Spleen sections were characterized by hyperplasia of germinal follicles and capillary congestion. Whereas thymus from group 6 showed severe congestion and hemorrhage , while thymus section from group 7 showed slight congestion and multifocal area of hemorrhage. Group 5and 8 which vaccinated with intermediate plus vaccine showed more severe histopathological changes which characterized by severe destruction of bursal structure and severe destruction of spleen structure. Thymus section of group 5and 8 were exhibited depletion of lymphocytes in medulla with multifocal area of hemorrhage and congestion.
Indirect ELISA test revealed that the mean of maternal derived antibody (MDA) at one day old chicks was 4852±745. Significant differences (P<0.05) among means of antibody titers of all vaccinated groups were found at 21st ,28th and 35th day of age compared with that of control group. The results also showed that groups which were vaccinated with intermediated plus vaccines exhibited high level of antibody especially groups 5 and 8 than those which vaccinated with intermediate vaccines.
The results of competitive ELISA test showed that significant increase (p<0.05) in the level of corticosterone (CS) hormone in group 5 at 24hrs, while the level of CS was highly significant increase (p<0.05) in group 4, 5 and 8 at 48 hrs post vaccination. However, there were significant increase (p<0.05) in group 5 and 8 at 72 hrs as compared with that of control group.
This study demonstrated that NOBILIS D78, VOLVA IBDMLV, GUMBORO VAC, NOBILIS E228, HIPRA GUMBORO-GM97 vaccines were able to produce sufficient antibody titers, and did not produce stressful conditions to the vaccinated birds.
The study does not recommend using of BURSINE-2, AVIPRO PRECISE, BURSINE PLUS vaccines because these vaccines are highly injurious to the bursa of Fabricius, spleen and thymus and produce stressful condition to the vaccinated birds

السلام عليكم ....
دكتور ابراهيم المحترم ..
دكتور مهند الغالي المحترم ...
لا شكر على واجب اخوتي الافاضل فأنتم أهل الذوق والاصول والخير والبركة ..
تستاهلون ماء العين وربي ...
لكم مني فائق الشكر والتقدير ....
تحياتي

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