During 30 nine months of sampling, the prevalence was surveies in C. livia of Rohilkhand part of Uttar Pradesh, India, harmonizing to the sex of the host, different seasons and vicinities where the pigeons were obtained. Datas on the happening of Haemoproteus and Plasmodium showed the maximal per centum of infection ( 55.63 % ) in C. livia during the full period of survey. Out of 266 pigeons sampled, 148 pigeons were positive for Haemoproteus at a prevalence of 55.63 % . Merely 18 pigeons ( 2.67 % ) had a assorted infection with Haemoproteus and Plasmodium and 130 pigeons ( 48.87 % ) had Haemoproteus infection entirely and no pigeons were positive for Plasmodium entirely. Parasite incidence in relation to the sex of the host indicated a higher infestation in females ( 62.79 % ) than males ( 57.65 % ) . The overall highest infectivity of parasites was recorded during the summer season ( 82.85 % ) followed by spring season ( 59.37 % ) and least in the winter season ( 42.30 % ) . It was besides observed that Haemoproteus occurred at diverse infectivity in C. livia from different vicinities ( Badaun-51.35 % , Bareilly- 11.18 % and Shajahanpur-58.06 % ) whereas Plasmodium was recorded 11.18 % merely from Bareilly. This parasite was wholly absent from the other two sites.
Cardinal words: Haemoproteus, Plasmodium, pigeons, prevalence, seasons, sex.
In bird, the prevalence of haematozoan blood parasites has been used to analyze hypothesis of sexual choice ( Hamilton and Zuk, 1982 ; Read, 1987 ; Zuk, 1991 ) , immuno-competence ( Mc Curdy et al. , 1998 ; Nordling et al. , 1998 ) and the costs of reproduction ( Norris et al. , 1994 ; Richner et al. , 1995 ; Wiehn et al. , 1999 ) . Studies on parasite-host interactions have revealed many of the most sophisticated illustrations of development, including adaptative use of host behavior ( Lafferty and Morris, 1996 ) and host sex ( Hurst et al. , 1993 ; Vance, 1996 ) .
Parasites may exercise hurtful effects on their hosts as indicated by Hamilton and Zuk ( 1982 ) . Indeed the traditional position that parasites are comparatively benign ( Cox, 1989 ) has been repeatedly challenged ( Toft and Karter, 1990 ) and parasites are now regarded as holding potentially negative effects on the endurance and fittingness of the avian hosts ( Atkinson and Van Riper, 1991 ; Raidal and Jaensch, 2000 ) .
Parasites can besides increase susceptibleness to predation ( Vaughn and Coble, 1975 ) and high parasite strength is in some instances associated with decreased look of sexually selected traits ( Seutin 1994 ; Thompson et al. , 1997 ) . Overall nevertheless, the impact of parasites on their hosts and the physiological mechanism underlying this impact remain ill understood ( Toft, 1991 ) . However, the avian plasmodia are of import protozoon parasites because they are utilised extensively for ecological mold of host-parasite systems ( Hamilton and Zuk, 1982 ; Read 1988 ; Atkinson and Van Riper, 1991 ) . Ecologists, ethologists and wildlife disease workers now are acknowledging the importance of informations on distribution and prevalence of avian malaria for the survey of ecological, behavioural and evolutionary jobs originating in host parasite systems.
Variation in parasite prevalence and in the strength and happening of interspecies associations among parasites should be of import for predictory impact of parasites on host populations. Factors that can account for fluctuation in parasite prevalence or strength include: host genotype ( Gregory et al. , 1990 ) , host size ( Blower and Roughgarden, 1988 ) , age or sex of host ( Schall, 1983 ) , host status ( Forbes and Baker, 1990 ) and host generative attempt ( Festa-Bianchet, 1989 ) . Factors extrinsic to hosts, such as geographical part ( Krikpatrick et al.,1991 ) and clip of season or twelvemonth ( Weatherhead and Bennett, 1991 and 1992 ) are besides of import because they can act upon the distribution and copiousness of infection phases or vectors.
In avians, the consequence of parasites on host ecology has been ignored. Recently, the position that good adapted parasites do non harm their hosts, has been challenged and there is turning grounds that parasites do hold a present twenty-four hours consequence on a great assortment of host fittingness constituents.
The position that commensalisms is the lone outsome of host-parasite interaction has been challenged and during the last decennary, wonder in parasites and their hosts has risen ( Price, 1980 ; Loye and Zuk, 1991 ; Toft et al. , 1991 ) . The survey of host parasite interaction has focused chiefly on the Fieldss of population ordinance ( Anderson and May, 1978, 1979 ) , coevolution ( Toft et al. 1991 ) and ecology ( Loye and Zuk, 1991 ) every bit good as behavioural ecology ( Loye and Zuk, 1991 ; Keymer and Read, 1991 ) .
MATERIALS AND METHODS
Columba livia Gmelin weighing 400-500gms were collected from different vicinities of Rohilkhand part of Uttar Pradesh, India.. They were kept in separate coops and maintained in the research lab under suited environmental conditions of aeration and nutrient. Blood was collected straight from the clipped nail by a fingernail limiter or from the brachial vena, a bead placed on a clean microscopic slide and blood vilifications were prepared and stained in Giemsa ‘s with phosphate buffer ( pH 7.4 ) in the ratio of 1:7 for 3 hours. The slides were washed, dried and examined for blood parasites at 100x. Parasite species were identified utilizing structural features ( Garnham, 1966 ) . Parasitaemia were calculated from counts of 100 ruddy blood cells at x1, 000 harmonizing to different vicinities viz. Site-1 ( Badaun ) , Site-2 ( Bareilly ) and Site-3 ( Shahjahanpur ) , seasons and sex of the host population on parasite incidence. To detect the consequence of the seasons, the whole twelvemonth was divided in to four seasons, Spring ( March – May ) , Summer ( June – August ) , Autumn ( September – November ) and Winter ( December -February ) and the information was recorded and tabulated in each of them.
Haemato-parasitological scrutiny of thin blood vilifications of Columba livia revealed hematozoa of chiefly two genera, Haemoproteus and Plasmodium. Data on the happening of Haemoproteus and Plasmodium showed that Haemoproteus occurred at a higher prevalence ( 55.63 % ) in Columba livia as compared to Plasmodium ( 6.76 % ) . Out of 266 pigeons sampled, 148 pigeons were positive for Haemoproteus at a prevalence of 55.63 % . Merely 18 pigeons ( 2.67 % ) had a assorted infection with Haemoproteus and Plasmodium and 130 pigeons ( 48.87 % ) had Haemoproteus infection entirely and no pigeons was positive for Plasmodium entirely. The average burden of Haemoproteus for septic pigeons was 1.68 Gametocytes/100 RBC ‘s runing from 1 to 6 Gametocytes/100 RBC ‘s whereas for Plasmodium it was 1.38 Gametocytes /100 RBC ‘s and varied from 1.0 to 2.0 Gametocytes/100 RBC ‘s. In add-on, when the infection rates were calculated harmonizing to the vicinities the highest infectivity of Haemoproteus ( 58.06 % ) was observed in pigeons collected from Shahjahanpur ( site 3 ) whereas the lower limit ( 51.35 % ) occurred from Badaun ( site-1 ) . In instance of plasmodium it was occurred merely in Bareilly ( site-2 ) at a prevalence of ( 11.18 % ) and the parasitemia was 1.38 gametocytes/100 RBC ‘s. This parasite was wholly absent from the other two sites ( site 1 and 3 ) Haemoproteus in C. livia besides showed highest concentration index of 2.77 Gaematocytes/100 RBC ‘s from Shahjahanpur ( site 3 ) and a lower limit of 1.39 Gametocytes/100 RBC ‘s from Badaun ( site 1 ) whereas it was 1.58 Gametocytes/100 RBC ‘s from Bareilly ( site 2 ) . The infection rates were besides calculated harmonizing to different seasons. In general, the highest infectivity of Haemoproteus occurred during the summer season fallowed by spring season and least in the winter season. In instance of Plasmodium infection, the infectivity was recorded merely in spring and fall season. The pigeons were free from Plasmodium infection in summer and winter seasons. In summer seasons, Haemoproteus showed the highest ( 82.85 % ) frequence index followed by ( 59.37 % ) spring season. Therefore, a decreased ( 48.14 % ) in the infection rate was observed in the fall season and the lowest infection ( 42.30 % ) was found in the winter season. It was besides noticed that concentration index was besides comparatively higher ( 3.44 Gametocyte/100 RBC ‘s ) in summer season and reached its extremum in the month of July during summer season. A 100 % frequence index and 4.33 Gametocytes/100 RBC ‘s ( concentration index ) was recorded in the same month. The minimal concentration index ( 1.0 Gametocytes/100 RBC ‘s ) were recorded in the fall and winter grounds while in instance of Plasmodium, the highest frequence index ( 34.37 % ) was recorded in the spring season when the concentration index was 1.54 Gametocytes/100 RBC ‘s. The minimal frequence index ( 25.92 % ) and 1.0 Gametocytes/100 RBC ‘s ( concentration index ) of Plasmodium occurred during the fall season. It was besides noticed that pigeons were free from Plasmodium infection during the summer and winter seasons. When the infection rates of Haemoproteus were reassessed harmonizing to the sex of the host it varied from 62.79 % in females and 57.65 % in males. The parasitemia burden of Haemoproteus was 2.22 Gametocytes/100 RBC ‘s in females and 1.68 Gametocytes/100 RBC ‘s in males. In instance of Plasmodium, merely five females and 13 male were infected with this parasite. The concentration index of the parasite was 1.0 Gametocytes/100 RBC ‘s in females and 1.53 Gametocytes/100 RBC ‘s in males.
During the present class of survey, blood parasites were rather abundant but their distribution and prevalence markedly varies from part to part and from one avian household to the other in the Indian Subcontinent ( Nandi and Bennett, 1997 ) . Life rhythm surveies on species of Haemoproteus, peculiarly those affecting vector surveies of the other genera of blood parasites should be approached with cautiousness and undertaken in those parts where it is obvious that both abundant infections occur in the ferine avian populations, a prevalence that will bespeak the handiness of suited vector in the country.
The comparative frequence of different parasites species found in this survey agreements with old findings demoing that the most common avian blood parasite is Haemoproteus ( Desser and Bennett, 1993 ) . Levine and Kantor ( 1959 ) found a scope of 28 to 100 % happening of Haemoproteus in domestic pigeons. Surveies, to day of the month, have determined that the most common blood parasite found in pigeons is Haemoproteus and infection rate may be every bit high as 75 % runing from 6 to 86 % ( Stabler, et al. , 1977 ; Qureshi and Sheikh, 1978 ; Aguirre, et al. , 1986 ; Mandour et al. , 1986 ; Kaminjolo, et al. , 1988 and Subbiah and Joseph, 1988 ) . The highest prevalence ( 100 % ) of Haemoproteus in west Bengal India, was recorded by Nandi et Al. ( 1984 ) while Nandi and Bennett ( 1997 ) recorded 54.4 % infectivity of Haemoproteus and 34.6 % of Plasmodium in U.P. India whereas it was 36 % ( Haemoproteus ) and 33.3 % ( Plasmodium ) in Andhra Pradesh. The prevalence of Haemoproteus and Plasmodium, were besides recorded from Gujarat, Maharashtra and Punjab every bit good as 24.7 % and 0.4 % , 18.4 % and 1.1 % and 45 % and 2.0 % severally.
Surveies indicate that the incidence of infection differs in different sorts of birds and in different vicinities ( Fallis et al. , 1974 ) . Locality is one of the of import ecological factor which plays a bing function in the happening of parasite species. Because many birds migrate, the happening of parasites in birds in a peculiar vicinity is non needfully declarative of local transmittal. Incidence and degrees of parasitemia may bespeak, among other things, the susceptibleness of the bird, the handiness of suited vectors of the parasites, penchant of vectors for certain birds, and the comparative copiousness of different sorts of birds and vectors.
An probe on the frequence and concentration index of parasites collected from different vicinities indicates that site 3 ( Shajahanpur ) recorded highest frequence and concentration indices of Haemoproteus in Columba livia and relatively lower from site 1 ( Badaun ) whereas Plasmodium occurred merely from site 2 ( Bareilly ) .
The above findings indicate that extremely difference in infection of Haemoproteus between site 1 and site 3 was non important. Failure of this parasite to set up itself in some pigeons in sites 1 and 3, despite the presence of the vector host, could be attributable to a good wellness position of the host. Plasmodium infection occurred in 18 pigeons of 266 sampled from site 2. The low prevalence compared with that of Haemoproteus is perchance explained by a low prevalence or absence of vectors of avian Plasmodium, the Culex mosquitoes in the present country.
The present probe documented seasonal fluctuation in blood parasites ( Haemoproteus and Plasmodium ) infection in a free life population of pigeons. It was observed that prevalence of Haemoproteus was comparatively higher during summer season followed by spring. On the other manus, higher infectivity of Plasmodium occurred in spring season and it lowered during fall. There was no infection in summer and winter seasons.
The co-relation of parasite infection and parasitemia in Columba livia was besides worked out. It was observed that pigeons had merely 1.0 Gametocyte/100 RBC when the frequence index was lower in fall and winter season while in summer season when the infection was 82.85 % the pigeon showed a heavy parasitemia ( 3.44 Gametocyte/100 RBC ) . In the month of July in the same season when the infection was 100 % parasitemia reached a extremum ( 4.33 Gametocyte/100 RBC ) . In instance of Plasmodium parasitemia was recorded as 1.54 Gametocyte/100 RBC when the infectivity was 34.37 % in spring season whereas in fall season it was recorded 1.0 Gametocyte/100 RBC with the 25.92 % infectivity. Therefore, the per centum of infection was besides related to the blood of parasites ( parasitemia ) . Higher parasitemia and prevalence of Haemoproteus and Plasmodium during summer and spring season may be explained due to the increasing vector population during the same seasons and is co-related with engendering period of the host when the incidence was higher due to the fact that vectors besides become abundant during these seasons.
Our consequences are in melody with earlier findings that highest parasitemia is found in summer and spring seasons. Jordon ( 1943 ) recorded the proportion of Haemoproteus septic birds ( Blue-joys ) tended to lift as the summer but the incidence of malaria in sparrows reached its upper limit in June and July. Micks ( 1949 ) besides made similar survey of English sparrow and found a good trade of malaria in May and July. Mandal ( 1990 ) observed the same incidence in pigeons from Garia, Calcutta and Manwell ( 1955a ) observed that septic birds are most likely to demo plasmodia in the blood in spring season. Highest infection rates of Haemoproteus were observed during autumn and winters by several writers ( Klei and Deguisti, 1975 ; Stabler et al. , 1977 and Ahmed and Mohammad, 1978 ) while Markus and Oosthuizen ( 1972 ) reported the absence of seasonal fluctuation of Haemoproteus in pigeons from Pretoria, South Africa.
Seasonal extremums of haemosporidian happening during summer and spring are suggested to be due to the physiological alterations during reproduction ( Dorney and Todd, 1960 ) or may be due to migratory birds ( Herman,1938 ; Manwell, 1955a ; Janovy, 1966 ) . Experimental grounds has been obtained back uping the hypothesis of tradeoff between generative attempt and the efficiency of the immune responses that control parasite infection.
Ahmed and Mohammad ( 1978 ) concluded that pigeons transporting chronic or latent infections, are immune to super infection by shooting sporozoite with physiological saline solution. Bennett ( 1970b ) stated that phagocytosis plays a major function in look intoing the figure of parasites. Brown ( 1976 ) indicated an active Ig synthesis in malaria infection in add-on to macrophage activation and suggested that phagocytosis of merozoites is mediated by opsonins. Presumably gametocytomia with Haemoproteus is controlled by the physiology of the host species and to some extent, by the figure of septic bites.
Parasite incidence in relation to the sex of the host has received small attending. Surveies look intoing sexual differences in blood parasite strength have provided variable consequences. In Great breasts, parasite prevalence was higher in females than males ( Norris et al. , 1994 ) . In brown-headed cow birds, parasite prevalence increased during summer in females than males ( Weatherhead and Bennett, 1992 ) . In contrast, male red-winged Black birds were more to a great extent parasitized with leucocytozoides than conspecific females ( Weatherhead and Bennett, 1991 ) . Merila et Al. ( 1995 ) recorded no important sex differences in overall prevalence of Haemoproteus Chloris. Forbes et Al. ( 1994 ) found no important sex difference in the prevalence of Haemoproteus and Plasmodium. Sexual activity of hosts have been shown to associate to fluctuation in prevalence of blood parasites in other extended surveies on birds ( Gibson, 1990 ; Atkinson and Van Riper, 1991 ; Weatherhead and Bennett, 1991, 1992 ) .
During the present classs of survey a higher infestation ( 62.79 % ) was recorded in female than male pigeons ( 57.65 % ) while in instance of Plasmodium. The frequence index was higher ( 11.71 % ) in males than females ( 5.81 % ) . The related work by other workers as shown above indicates variable consequences of parasite infestation in relation to the sex of the host. Males and females may differ with regard to facets of their behaviour that modify exposure to insect vectors, opposition to infestation, and or the ability to contend and extinguish acquired infections possibly as a consequence of sex-specific interactions with environmental conditions ( Wiehn and Korpimaki, 1998 ) . On the contrary, Device et al. , ( 2001a ) did non uncover the sexual differences in parasite prevalence, nevertheless strength of infection declined in males in summer but non in females. As a consequence, males and females had a similar strength of infection, but females had higher strengths than males in September.
In add-on, it is rather likely that the strength of the parasitemia is straight related to the physiological position of the host and the emphasis lading on its immune system from other factors unrelated to the presence of blood parasites. It may be therefore assumed that the different grades of strength of infection in males and females is non simply the consequence of hormonal differences but largely depends on the ecology of parasite vectors and physiology of their hosts.
Table 1: Overall Incidence of Haemoparasites in Columba livia
No. of examined hosts
No. of septic hosts
Frequency Index ( % )
Concentration Index ( /100 RBC ‘s )