Hostname: page-component-586b7cd67f-t8hqh Total loading time: 0 Render date: 2024-11-25T00:15:24.807Z Has data issue: false hasContentIssue false

Studies on Tissue Responses in Primary and Subsequent Infections with Heterakis gallinae in Chickens and on the Process of Formation of Caecal Nodules*

Published online by Cambridge University Press:  18 November 2009

R. K. Kaushik
Affiliation:
Division of Pathology, Indian Veterinary Research Institute, Izatnagar (U. P), India
V. P. Sharma Deorani
Affiliation:
Division of Pathology, Indian Veterinary Research Institute, Izatnagar (U. P), India

Extract

1. In primary infections of chicks with 300 or 600 H. gallinae infective eggs, no clinical signs were apparent. Nodules were absent in all the experimental chicks as well as controls. Microscopically, few juveniles were observed in the caecal mucosa and the usual changes were mild congestion, few haemorrhages, and desquamation of superficial lining epithelial cells. Sections through a few thickened areas revealed a breached muscularis mucosa through which proliferated mucosal tissue had just invaginated into submucosa. The liver showed no changes.

2. With primary infection of chicks with 300 or 600 infective H. gallinae eggs, and their subsequent infection after 25 days with 1,000 infective eggs, there were no clinical signs after either primary or secondary infections. Nodules of varying sizes were present on the caecal wall of infected birds only, their size and number varying with age of infection. Histopathologically, the types of nodules observed were, one associated with juveniles and the other with their absence; and nodules were present both in the invaginated mucosa and in the submucosa. It was confirmed that these caecal nodules were due to irritation by H. gallinae juveniles and their metabbolites, and that these nodules were more a reaction of already sensitised caeca to subsequent infections, a fact hitherto unreported. The liver showed nothing abnormal, and there was not much difference between the haematological values of experimental and control chicks.

3. The actual process of formation of caecal nodules is demonstrated for the first time. The feasible explanation seems to be that on irritation of the already sensitised caeca by H. gallinae juveniles and their metabolites, hyperplasia of lymphoid tissue and epithelial cells results, which leads to a breach of the muscularis mucosa through which proliferated tissue of the mucosa invaginates. Later the muscularis mucosa constricts off and closes the nodule, the mucosa over it regenerates and becomes continuous. The present observations also indicate that the sterile nodular lesions usually found in natural infections may be the result of frequent infections, thus sensitising the chicks to subsequent infections.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1969

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Baker, A. D., 1931.—“Some pathological conditions found in the caeca of fowls.” Poult. Sci., 8, 5976.CrossRefGoogle Scholar
Clapham, P. A., 1933.—“On the life-history of Heterahis gallinae.” J. Helminth., 11, 6768.CrossRefGoogle Scholar
Clapham, P. A., 1934.—“Some observations on the response of chickens to infestation with Heterakis gallinae.” J. Helminth., 12, 7178.CrossRefGoogle Scholar
Clapham, P. A., 1937.—“On some lesions associated with helminths of birds of economic importance.” J. Helminth., 15, 4952.CrossRefGoogle Scholar
Deo, P. G. and Srivastava, H. D., 1962.—“The acquired resistance of chickens to Heterakis gallinae (Gmelin) Freeborn.” Indian J. vet. Sci., 32, 139142.Google Scholar
Grigorev, N. K., 1959.—“The role of H. gallinae in the formation of nodules in the caecum of domestic fowls.” Trudy. mosk. vet. Akad., 25, 237244.Google Scholar
Grigorev, N. K., 1959 a.—“Pathological changes in the caecum and liver of domestic fowls infected with Heterakis.” Trudy. mosk. vet. Akad., 25, 245254.Google Scholar
Itagaki, S., 1930.—“The nature of the parasitic nodules in the caecal wall of fowls and the development of Heterakis vesicularis.” 4th Wld Poult. Congr. London, p. 481483.Google Scholar