1.
A Study On Pathology And Haematology Of Broiler Chickens Experimentally Infected With Salmonella
by Younus, M | Dr. Shahzada Khurram Ashraf | Dr. Mubasher | Dr. Shakeel Akhter Khan | Faculty of Veterinary Sciences.
Material type: ; Format:
print
Publisher: 1994Dissertation note: The investigation was conducted to study the pathology and Haemotology of broiler chickens suffering from experimental salmonella gallinarum infection. Total of 140 day did broiler chicks were reared upto 3 weeks of age and were fed on commercial poultry feed. The birds were randomly divided into four groups i,e. A, B, C and D containing 35 chicks in each group. The inoculation of broiler chicks of experimental groups were done at the age of two weeks at a dose rate of 1ml per bird through different routas ic group A through oral route, group B through subcut, group C through I/rn and group D was kept as control. All the groups were kept under close observation to record signs and symptoms. At the age of 3 weeks (7 days of post infection) the birds of experimental and control groups were slaughtered for the study of haematological parameters (Fib estimation, TEC and TLC), gross and histopathological lesions in visceral organs (Heart, Liver, lung, spleen and kidneys)
Antemortem symptoms were recorded throughout the experiment in all the infected groups and observed listlessness with ruffled feathers, droopy wings, poor growth, weakness, loss of appetite, adherence of whitish material to vent, laboured breathing, slight depression and increased thirst. Conjunctivitis and arthritis in few cases were observed.
The postmortem changes observed in all the infected groups A, B and C at the age of 21 days (7 clays post infection) included enlarged heart, necrosis of myocardium, pericarcil tis, enlarged creamy white liver with pin point haemorrhages, congested lungs with necrotic loci ple.nomegaiy. and swollen kidneys with c1isco1.oiration and triable consistency. No lesions could be observed in control group D.
Haemotological alterations were studied in all the groups i ,e A, B, C and D. There was a significant decrease in haemoglobin concentration, total erythrocytic count amongst all the infected groups A, B and C at 21 days of age (7 clays post infection) as compared to control group D. but: the total leukocytic count showed a significant increase in all the infected groups, i, e. A, B and C as compared to control group D at the 21 clays of age.
The main histopathological lesions observed in al .1 the infected groups A, B and C at the age of 21 clays (7 clays of post infection) in heart, liver, lungs, spleen and kidneys included necrosis, haemorrhage and leukocytic: infiltration. However, in few cases fatty destrophy, congestion and degenerative changes were also observed. No histopathological lesion could be observed in control group D.
From present study it was concluded that fowl typhoid caused by Salmonella gallinarum infection resulted in higher mortality and pathological changes especially through intramuscular route as compared to other routes of infection.
Availability: Items available for loan: UVAS Library [Call number: 0370,T] (1).
2.
Pathological Changes Associated With Experimental Infectious Bursal Disease In Broiler Chickens
by Nyla Dil Tarar | Dr. Shakeel Akhter Khan | Dr ..S. Ata-Ur- Rehman Rizvi | Dr. Ahmed Raza | Faculty of Veterinary Sciences.
Material type: ; Format:
print
Publisher: 1995Dissertation note: This project was designed to study the pathological changes associated with experimental Infectious bursal disease in broiler chickens. Two hundred and forty broiler chicks on 21 days of age were randomnly divided into six groups, A through F, each containing 40 birds. The inoculum of Infectious bursal disease virus was inoculated intraocularly in the chicks of group A at the age of 21 days, in group C at the age of 28 days, and in group E at the age of 35 days. Groups B, D and F were kept as control for groups A, C and E respectively. Blood samples and lymphoid organs of seven randomnly selected chickens from each group were collected at day 4 post inoculation (P1), 8 P1 and 12 P1, and haematology (TLC, DLC), serology (AGPT) and histopathology of lymphoid organs were conducted.
Typical clinical signs of IBD were noted. The chief and consistent gross lesion produced in the chickens infected at different ages was an initial increase in the size of bursa. At day 4 P1 bursa was oedematous and double in size but at days 8, 12, P1 it was smaller in size than in control chickens. The spleen and thymus appeared almost normal grossly except a few gray foci on spleen.
Histopathological study of bursa of Fabricius (regardless of the age at infection) revealed an initial macrophage and heterophil infiltration of the lymphoid follicle and inter-follicular spaces followed by increased inter-follicular connective tissue, plasma cells, macrophage and thickening of bursal epithelium. Spleen showed lymphocytic necrosis and depletion in the initial stages followed by repopulation. Statistical analysis of lymphoid organ: body weight indices of spleen, bursa and thymus showed a significant difference in the inoculated and control chickens but there was no difference in the chickens inoculated at different ages. All the inoculated birds were found positive for the Infectious bursal disease virus antibodies. The results of hematological study indicated that there was a decrease in the total number of leukocyte and percentage of hetrophils and lymphocytes in all the inoculated chickens regardless of the age at the time of infection. Thus it can be concluded from this study that age susceptibility, from 21 to 35 days, among broiler chickens for Infectious bursal disease was nearly the same.
Availability: Items available for loan: UVAS Library [Call number: 0436,T] (1).
