STUDIES ON PROTOZOAN INFECTION OF DOMESTIC PIGEON (Columba livia domestica) IN ASSAM
Loading...
Date
2016-07
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
Assam Agricultural University, Khanapara, Guwahati
Abstract
To understand the pattern of protozoan disease in domestic pigeon of Assam, a systematic study was conducted for a period of one year. A total of 324 blood samples of pigeons were screened for detection of haemoprotozoan infection and 173 birds were found positive by microscopic examination of blood smear, the overall percentage being 53.39%. Three different species of haemoprotozoa viz. Haemoproteus columbae, Plasmodium relictum and Leucocytozoon sp. were identified in pigeons of Assam. Prevalence of haemoprotozoan infection was analyzed on the basis of age and sex of birds and season of the year.
Examination of body of pigeons for the presence of pigeon fly, Pseudolynchia canariensis, the proven vector of Haemoproteus columbae showed 15.12% prevalence.
Among the haemoprotozoan parasites, Haemoproteus columbae was predominant (29.93%) followed by Plasmodium relictum (21.29%) and Leucocytozoon sp. (2.16%) was recorded least. Morphologically, the three species were identified and confirmed. Age wise, infection was recorded highest in adults (61.81%) and least in squab. Sex wise, female (58.22%) showed more infection as compared to male birds. According to season infection rate was highest (72.55%) in premonsoon season. Microfilaria of Bhalfilaria ladamii was also detected during examination of a heart blood smear. Examination of a blood smear also revealed trophozoites of Trichomonas gallinae as an accidental case. Haematological parameters recorded in infected and non infected birds due to haemoprotozoan parasites showed significant differences in Hb, PCV, TEC, MCV, MCH, heterophils, lymphocytes, eosinophil values between the two groups.
The prevalence of Trichomonas gallinae infection based on throat swab smear examination was recorded as 26.85%. Age wise highest prevalence was found in squab (56.25%) and lowest percentage in adult (10.90%). Sex wise prevalence was higher in female (33.54%) than male birds. Season wise highest prevalence of Trichomonas gallinae was found in winter season (34%) and least infection was observed in post monsoon season (21.44%). Prevalence of mixed infection of Haemoproteus columbae and Trichomonas gallinae were highest (12.34%).
A total of 438 fresh pooled faecal samples were collected from pigeons irrespective of age and sex from four different districts of Assam viz. Kamrup (R), Kamrup (M), Lakhimpur and Dhemaji district for detection of coccidia and other associated helminthic infection. Overall prevalence of coccidia infection was found to be 38.81%. Species wise highest prevalence was recorded due to Eimeria labbeana (28.08%), followed by Eimeria columbarum (6.84%), Eimeria columbae (2.86%), Isospora sp.(0.22%). One unidentified Eimeria sp. (1.14%) was also put on record having morphological similarity to E. duculai. Mixed infection of coccidia and Capillaria sp. egg was detected highest (5.93%), followed by Heterakis gallinarum (3.19%), Ascaridia columbae (1.82%) and Strongyloides avium (0.91%). Season wise prevalence rate was recorded highest in premonsoon season (61.22%), followed by monsoon (34.78%), post monsoon (34.73%) and least in winter (28.46%).
Experimental infection of coccidia and Trichomonas gallinae done for establishment of pure infection revealed clinical symptoms and presence of parasites. Pathological alterations and the microscopical changes induced by Trichomonas gallinae and coccidia were studied on 55 carcasses of pigeons collected from temple premises and households of the present study area. At post mortem, 10 nos. of carcasses (18.18%) showed positive lesion due to coccidia and 14 nos. of carcasses (25.45%) showed lesions due to Trichomonas gallinae. Gross pathological changes due to coccidia were haemorrhagic and necrotic lesion in the intestinal mucosa, thickening of intestine and excessive mucus production and in case of Trichomonas gallinae, there was accumulation of greenish- white necrotic haemorrhagic lesions in the crop and oesophagus, and areas of necrosis in liver and gizzard.
Histopathology of intestinal mucosa revealed diffuse areas of haemorrhages and detection of oocysts of coccidia. In case of Trichomonas gallinae infection, microscopical changes seen in liver were coagulative necrosis and inflammatory reaction. Crop showed areas of moderate haemorrhage and congestion and varying amount of inflammation. In the lung, parenchyma showed thickening, congestion of blood vessels and haemorrhage. Myocardium of heart also showed congestion and focal areas of haemorrhage.
Polymerase chain reaction (PCR) was performed for identification of cyt b gene of Haemoproteus columbae using oligonucleotide primers. The positive blood samples produced amplification of 207bp. PCR for amplification of mt-cyt b gene of Haemoproteus spp. and Plasmodium spp. was also carried out and positive samples showed the clear band at 525 bp. Amplification of ITS-1 gene for detection of Eimeria genus was also performed and the positive samples showed clear band at 510 bp. Similarly, amplification of ITS1/5.8SrRNA/ITS2 gene was done for identification of Trichomonas gallinae and clear band at 290 bp was seen in positive samples. On the basis of phylogenetic analysis, local isolate (Haemoproteus columbae) is highly dissimilar from reported isolates of nearby and distant countries.
Description
Keywords
null