Seasonal distribution of parasites in freshwater exotic ...

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*Corresponding authors’ e-mail: [email protected], [email protected].

Indian J. Anim. Res., 49 (1) 2015: 95-102Print ISSN:0367-6722 / Online ISSN:0976-0555

Seasonal distribution of parasites in freshwater exotic carps of West Bengal, IndiaGadadhar Dash*, Debolina Majumder and Raghu Ramudu K.

Department of Aquatic Animal Health,Faculty of Fishery Sciences, West Bengal University of Animal and Fishery Sciences,5, Budherhat Road, Chakgaria, Kolkata- 700 094, India.Received: 02-07-2012 Accepted: 21-11-2012

ABSTRACTThe study has been carried to find out the distribution of different parasites in Exotic carps with respect to different monthsand seasons. These were isolated and identified from the fishes sampled randomly from five fish markets, which wererepresenting South 24 parganas district, West Bengal. During the study period ten different types of parasites were observedsuch as Trichodina sp, Chilodonella sp, Trichinella sp., Acanthocephala sp, Nematodes, Epistylis sp, Zoothamnium sp,Vorticella sp, developmental stages of eggs or parasites and some parasites (unidentified) among which most of the parasiteswere protozoan. Among all the parasites the most dominant were Trichodina sp, Chilodonella sp and Nematodes. Winterwas the most vulnerable period to get parasitic infestation. During this period the water quality get deteriorated and thefishes were in stressed condition which favours the parasites to infest. Some parasites were found more during summerwhich favours their reproduction due to the availability of their intermediate host. In monsoon the temperature fluctuateswhich also favours growth of some parasites. During the study period Trichinella sp were found solely in Cyprinus carpioexclusively in winter.The protozoan parasites were most available during winter and these were the dominant parasites inexotic carps. These parasites were found mostly on gills and skin of the fishes where as nematodes were found in theintestine and body cavity of the fishes.

Key words: Ecto-parasites , Endoparasites, Exotic carps, Seasonal distribution.

INTRODUCTIONThe exotic carps, Silver carp (Hypopthalmicthys

molitrix), Common carp (Cyprinus carpio) and Grass carps(Ctenopharyngodon idella) are commercially important butthey also possess risk of diseases. The increasingintensification of fish production and lack of healthmanagement measures have lead to many disease problemsof bacterial, viral, fungal and parasitic origin. About 80% offish diseases are parasitic especially in warm water fish (Eissa,2002). Ecto-parasites are the most dangerous group thatcauses severe mortalities. There have been many instancesof transfer of disease or parastic organisms from wild grasscarps to other countries and species. Silver carp have alsobeen known to harbor a type of Salmonella bacteria whichcould be devastating to natural fish populations. Accordingto Tatcher (1981) many parasites can live in a host, sometimescausing damage, sometimes not. Parasitic infection anddiseases are some of the factors hindering high productivityin fish farming.

MATERIALS AND METHODSThe study on parasites of exotic carps was carried

out for a period between July 2010 and June 2011. The

samples (20-30 fishes) were collected on monthly basis fromfive different fish markets namely Garia, Bansgaria, Kalitala,Mukundapur and Jadavpur in the district of South 24Parganas, West Bengal, India. The vital organs like skin,intestine, kidney and gills were examined for the presence ofdifferent parasites. The methods for collection,fixatation andpreservation of the samples for parasitic examination werefollowed as described by Soota (1980). Different groups ofparasites were identified based on the identifying charactersas given by Soulsby (1982).The parasitic frequency index(PFI) was calculated by taking the percentage of the numberof hosts infected by an individual parasite species against thetotal number of hosts examined in a particular area underinvestigation. The frequency index were further classified intorare (0.1 – 9.9%), occasional (10-29.9%), common (30 –69.9%) and abundant (70-100%) as per Srivastava (1980).One way ANOVA was done to determine the significance ofdifferences in Parasitic Frequency Index (PFI) of parasitesamong different seasons as well as different months. Duncan’sTest at 1% and 5% were done to know the significance ofdifferences at microlevel .As the Parasitic Frequency Index

doi: 10.5958/0976-0555.2015.00020.5

96 INDIAN JOURNAL OF ANIMAL RESEARCH

was recorded in percentage values and these were rangedfrom 0 to 100, angular transformation was done beforeanalysis.Formula for angular transformation:

x= Sin-1 PercentageAll statistical calculation was done on a desktop PC

using SPSS (Ver. 12.0).

RESULTS AND DISCUSSIONDuring the study period a total of 253 numbers of

Hypopthalmicthys molitrix, 255 numbers of Cyprinus carpioand 260 numbers of Ctenopharyngodon idella wereexamined.

Prevalence of Trichodina sp in Exotic Carps: Trichodinasp. in Hypopthalmicthys molitrix were highest during themonth of December and January (PFI: 56.00% and 47.83%);while their presence were very low during June (13.33%). InCyprinus carpio the prevalence of Trichodina sp were highestduring December and January (PFI: 68.00% and 59.25%),and lowest during June. In Ctenopharyngodon idella alsothe same pattern was observed where the prevalence ofTrichodina sp was highest during December and January (PFI:60.00% and 52.38%), and lowest during June (PFI: 16.66%).Thus in all three species, Trichodina sp was found in thegills and skin of the fishes and infestation was highest inwinter and lowest in summer (Table. 1, 2, &3).

In fish confined to ponds, tanks and aquaria,trichodiniasis is a frequent problem (Arthur and Lom, 1984).Water temperatures do not seem to be an important parameter,in spite of reports of low temperatures being more optimalfor reproduction of some trichodinids (Bauer et al., 1969),which corroborated with the present study. The highestinfestation with Trichodina sp. was found in winter, whilethe lowest infestation rate was in summer reported by Hassan,(1992) which supports the present findings. The results agreedwith the findings of McArdle (1984) and El-Khatib (1989)who reported that, Trichodiniasis was prevalent all over theyear with maximum rate of infestation during spring andwinter. The Trichodina infestation was highest duringDecember-February as reported by Hossain et al., (2008) alsosupported the present findings.

The probable reason for the higher prevalence ofTrichodina sp in fishes in winter may be that they have adirect life cycle, i.e. without involvement of any intermediatehosts. So the temperature may be the main factor of theirprevalence. On the other hand in winter the fishes become instressed condition which may also be the reason for theirhighest prevalence as it was reported that Trichodinds are

opportunistic parasites which become pathogenic understressful condition (Ahmed, 1976 and Eisa et al., 1985). Thereason may also be the overcrowding of fish in ponds ordeteriorating water quality due to low temperature assuggested by Sarig, (1968a) that the intensification of fishculture creates disease problems that originate fromovercrowdings. Dujin, (1973) reported deteriorating waterquality such as unsuitable water temperature is a reason fortrichodiniasis. Dogiel (1961a) also reported that trichodiniasisis caused by Trichodina sp.; the infection being stimulatedby the high density of fish in ponds as reported by Hossain etal. (2008) that, during winter when the water quality detoriatesdue to decrease of the temperature and dissolved oxygen levelthe Trichodina sp infestation was more because high stockingdensity increases the chance of ectoparasitic transmissionfrom fish to fish easily.

Prevalence of Chilodonella sp in Exotic Carps: The PFIof Chilodonella sp. in Hypopthalmicthys molitrix werehighest during December and January (PFI: 28.00% and26.08%). The occurrence of these parasites in Cyprinuscarpio reached to the peak during December (PFI: 32.00%)and were reached to the lowest in the month of May andJune (PFI: 8.69% and 5.00%). In case of Ctenopharyngodonidella also the parasite was found highest in the month ofDecember (PFI: 45%) and lowest in the month of June (PFI:11.11%). These were mostly found in the skin of the fishes.It was revealed that the prevalence of Chilodonella sp in allthe aforesaid fishes were highest in winter and lowest insummer (Table. 1, 2, &3).

Chilodonellas seem to be of a great ecologicaladaptability, proliferating both in cold and warm water. Underthese conditions which favour their proliferation,Chilodonellas may cover the body surface in a contiguouslayer . Shulman (1957) reported that all the members of genusChilodonella are mostly free living and two seriouspathogenic species infecting freshwater fish. According toPaperna et al. (1983) Chilodonella sp., are a frequentoccurrence in overwintering stocks of cultured tilapia hybridsin Israel, and O. mossambicus in ponds and dam reservoirsin southern Africa which corroborated with the presentfindings. Low water temperatures being more optimal forreproduction of Chilodonella piscicola and massive infectionswith Chilodonella sp occur in low (12–17°C) ambienttemperatures in southern Africa and Israel (Bauer et al., 1969)which also supports the present findings. Epizootics causedby C. hexasticha in Australia occurred during the wintermonths and the optimum temperature for C. cyprini is 5-10°C (Hoffman et al. 1979) which also corroborated theaforesaid findings.

97Vol. 49 Issue 1, (February 2015)

TABL

E 2:

Sea

sona

l abu

ndan

ce o

f par

asite

s (P

FI, %

) in

com

mon

car

p (C

car

pio)

from

Jul

y 20

10 to

Jun

e 20

11.

TABL

E 1:

Sea

sona

l abu

ndan

ce o

f par

asite

s (P

FI, %

) in

silve

r car

p (H

. mol

itrix

) fro

m J

uly

2010

to J

une

2011

.

PFI=

Para

sitic

Fre

quen

cy In

dex

(%).

a=ra

re (0

.1 –

9.9

%);

b=oc

casio

nal (

10 –

29.

9%);

c =

com

mon

(30

– 69

.9%

); d

= ab

unda

nt (7

0 –

100%

)


The probable reason for the highest availability ofChilodonella sp in winter may be due to the low temperaturewhich supports their reproduction. Hoffman, (1978) reportedthat a number of ciliates are facultative parasites, oropportunists which will colonise fish in special circumstances,most often when fish are stressed or traumatised. Epizooticscaused by these ciliates are relatively uncommon, unless hostsare stressed by poor conditions or crowding. So we can saythat as the fishes were in stressed condition during winter theoccurrence of Chilodonella sp were more in winter.Overcrowding during winter was also one of the reasons forstress in fishes and lead to higher prevalence of Chilodonellasp . During winter the water volume of fish habitat becomereduced and the parameters deteriorates leading to suffocationdue to lack of O2 in water, which may also be the anotherreason for highest prevalence of Chilodonella sp in winter.

Prevalence of Trichinella sp in Exotic Carps: TheTrichinella sp were not found in Hypopthalmicthys molitrixduring the study period. In Cyprinus carpio, Trichinella spwas found exclusively in the month of December and January,but in the rest of the months this species was not found. Thiswas found mostly in the gills and skin of the fishes. In caseof Ctenopharyngodon idella also these parasites were absentthroughout the study period (Table. 1, 2, &3).

In Sakon Nakhon (place) fish were infected with theinfective stage of Trichinella sp. Among these, cyprinid fishwere in the majority. The infection rate in these fishes rangedfrom 10 to 90%, with the highest rate in Pseudorasbora parvawith a metacercarial density of 160/fish (Rim, 1997). In 1982-1983, the prevalence were still high, varying from 7- 38%.The reservoir of these parasites includes domestic and wildanimals (Min, 1982). The probable reason for the availabilityof these parasites during winter may be due to the stress ofthe fishes. In winter the immune activity of the fishes slowsdown because of low temperature which may be responsiblefor the occurrence of these parasites. The environmentalcondition may be conducive for the prevalence of the parasitesduring winter.

Prevalence of Acanthocephalan sp in Exotic Carps: Theprevalence of acanthocephalans were more during the summerseason (March-April). The PFI of Acanthocephalan sp inCtenopharyngodon idella was highest during March(22.72%) and April (19.04%).This was found mostly in thegills and skin of the fishes. However, they were not found inHypopthalmicthys molitrix and Cyprinus carpio during thestudy period (Table. 1, 2, &3).

The results of the present study was in agreementwith that of Tweb and Ahmed (1981) who reported that the

Acanthocephalans was found more in summer. The seasonalfluctuation of Acanthocephalans is mainly influenced by thechanges in the feeding habits of the host (Awachie, 1966).Tweb and Ahmed; (1981), also suggested that the prevalenceof Acanthocephalans in summer may be due to their breedingseason, as gravid female and juveniles were also available inthat season. According to George and Nadakal, (1973), firstintermediate hosts of piscine Acanthocephalan are amphipods,isopods, copepods or ostracods. So we can say that the higherprevalence of Acanthocephalans during summer may be dueto the availability of intermediate hosts.

Prevalence of Nematodes in Exotic Carps: Nematodesprevalence were more in intestine and body cavity of the fishesof Cyprinus carpio and Ctenopharyngodon idella comparedto Hypopthalmycthys molitrix. These were dominant inmonsoon season than the winter and summer. InHypopthalmycthys molitrix Nematode infestation was highestin July (PFI: 42.85%) and lowest in April (PFI: 5.55%). Incase of Cyprinus carpio highest prevalence was observed inJuly (PFI: 52.17%) and lowest in April (PFI: 11.11%), whilein Ctenopharyngodon idella Nematodes were found highestduring July (PFI:44.00%) and lowest during April (PFI:14.28%),(Table. 1, 2, &3).

The results of the present study satisfied all thecriteria as reported by Pennycuick (1971). Pennycuick, (1971)and Kim et al., (2001) reported that seasonal distribution ofnematodes may be related to the fluctuation in temperature,presence of intermediate hosts and feeding habits of the hosts.Tweb and Ahmed (1981), reported that nematodes werecommon helminth parasites of freshwater fishes. The resultsof present study showed that nematode occurrence was morein monsoon than summer and winter. The probable reasonsbehind this may be due to the environmental condition whichwas conducive to these parasites, presence of firstintermediate hosts (copepod) and host specificity nature ofthe parasites.

Prevalence of Epistylis sp in Exotic Carps: Epistylis sp werefound only in Hypopthalmicthys molitrix during the monthsof December (12.00%), January (8.69%) and February(4.76%) on the skin and gills of the fishes, but they wereabsent in all the other months. So the observation revealedthat the occurrences of these parasites was found only in thewinter season. Epistyles sp was not found in Cyprinus carpioand Ctenopharyngodon idella during the study period(Table. 1, 2, &3).

In Europe, a few studies have noted the presence ofspecies of Epistylis on warm water fishes (Kahl 1935 andLom 1966). Rogers (1971), who found these parasites in pond


TABL

E 3:

Sea

sona

l abu

ndan

ce o

f par

asite

s (P

FI, %

) in

gras

s ca

rp (C

. ide

lla) f

rom

Jul

y 20

10 to

Jun

e 20

11.

fishes in Southeastern United States. Epistylis were often anectocommensal in that it simply attaches to the fish and feedson environmental debris such as bacteria. Poor quality waterencourages the growth of Epistylis on fish. The colonies ofthe Epistylis sp cause lesions (“red sore”) at the attachmentsite to the fish skin; these inflamed haemorrhagic lesions werealso contaminated with the bacterium Aeromonas hydrophila

During winter the water qualities of the ponddeteriorates due to lack of oxygen which may be the reasonfor the occurrence of Epistylis sp in winter. The infestationof these parasites was more during winter season due to theavailability of feed which agreed with the works ofDurborrow, (2003).

Prevalence of Zoothamnium sp in Exotic Carps:Zoothamnium sp were found in Hypopthalmicthys molitrixduring the months of November (4.34%), December(16.00%) and January (8.69%) though they were absent inthe rest of the months. These parasites were not found inCyprinus carpio during the study period. In case ofCtenopharyngodon idella these parasites were observed inthe months of December (20.00%) January (14.28%) andFebruary (5.00%) while they were absent in rest of themonths.They were found in gills and skin of the fishes. Theobservations revealed that these parasites were found only inthe winter and absent in other seasons (Table. 1, 2, &3).

Mohan (2007) reported that ectoparasitic protozoanssuch as Zoothamnium sp were often associated withmortalities of younger stages of cultured fish. The situationbecomes worst in waters with low oxygen and high organicmatter as most of these have simple and direct life cycleenabling them to multiply rapidly in such conditions, whichsupports the present findings as less oxygen and deterioratedwater quality , may be the probable reason for the prevalenceof these parasites during winter.

Prevalence of Vorticella sp in Exotic Carps: Vorticella spwere absent in Hypopthalmicthys molitrix during the entirestudy period. These parasites were found in Cyprinus carpioonly in the months of December (8.00%) and January(11.11%) while absent in other months. In Ctenopharyngodonidella these parasites were also observed during the monthsof December (15.00%) and January (9.52%) exclusivelythough absent in rest of the months. They were found in gillsand skin of the fishes. The observation revealed that theseparasites were found exclusively in winter but not in the otherseasons (Table. 1, 2, &3).

Scheubel (1973) reported that sessiline peritrichs (i.e.;Vorticella) found in fishes were ectocommensals that usetheir hosts as a living substrate to settle where they gain access


to a convenient source of food particles - organic debris andwater-born bacteria. They are specifically adapted to the lifeon the surface of certain species of fishes. Migala andKazubski, (1972), suggested that a great number of Vorticellidsteemed on the skin of debilited, moribund fish which lackingany defence reaction under adverse environmental conditions.These ciliates prey on the body surface of the fishes and feedon the tissues. The probable reason for the occurrence ofVorticella sp during winter in fishes may be due to adverseenvironmental condition or due to reduce immunity of the fishesas concluded from the aforesaid findings.

Prevalence of developmental stages of eggs/parasites inExotic Carps: Developmental stages of eggs / parasites wereobserved in the gills, skin and intestine of the three carps inall the months except May, June, September, October andNovember. In Hypopthalmicthys molitrix the highestprevalence were found in the month of December (52.00%)and January (47.82%). In case of Cyprinus carpio the highestprevalence were recorded 44.00% in the month of December.In Ctenopharyngodon idella the highest prevalence were35.00% in the month of December. All these observationsrevealed that the prevalence of these group of parasites werehighest in winter followed by summer and monsoon in allthe three exotic carps (Table. 1, 2, &3).

Low temperatures being more congineal forreproduction of Chilodonella piscicola and some trichodinids(Bauer et al., 1969) which supports the present findings. Theprobable reason for the availability of developmental stagesmore in winter may be due to the delaying of developmentalprocess at low temperature as suggested by Schaperclaus,1954, at a temperature of 15–17°C, the process of divisionof developmental stages of Ichthyothirius sp is lengthened.Davidov, (1978), found that temperatures below 15°C willdelay development of Asian tapeworm to 6–8 months whichalso supports the findings of Schaperclaus, (1954). Hoffman,(1980), reported that low temperatures seem to delay or eveninterrupt development and consequently completion of thelife cycle of tapeworms. At 28–30°C, 77% of the eggs hatchedin the first day after release, the remainder during thefollowing five days, where as at 14–15°C, the incubationperiod extended to 10–28 days and was for all practicalpurposes interrupted below 12°C which may also be thereason for the availability of developmental stages of eggsmore in winter.

Prevalence of parasites (Unidentified) in ExoticCarps: Some parasites were observed (unidentified) inHypopthalmicthys molitrix in most of the months exceptSeptember, October, February, April and May. The

highest prevalence were found in December (24.00%).In case of Cyprinus carpio the highest prevalence were24.00% in the month of December and these parasiteswere absent during the months of September, October,November, March and April. In Ctenopharyngodon idellathe highest prevalence were found in the month ofDecember(25.00%) and these parasites were not foundin the months of August, September, October, November,March, May and June. The overall observations revealedthe prevalence of these in gills, skin as well as intestineof the fishes and the highest occurrence of unidentifiedparasites were in winter in all the three varieties offishes(Table. 1, 2, &3).

Ahmed et al. (1991) observed that the prevalenceof diseases were more in the winter every year whichcorroborated the present findings. Dogiel (1961b) suggested15 factors, which directly influence the parasitic fauna offish. These factors include age, diet and abundance of fish,independence of the numbers of parasitic fauna within thefish and season etc. Wisheiwski (1958) stated that thecharacter of water body influences and determines theparasitic fauna of its community. The probable reason forthe availability of these parasites more in winter may bedue to the unfavourable water condition for fishes.

Distribution of parasites in different seasons: In the presentstudy most of the parasites showed a definite seasonal cycleof prevalence. The parasitic infection is greatly influenced bythe season, which basically interferes with ecology andphysiology of the fish. Several possibilities exist which mightaccount for the seasonal fluctuation in the prevalence ofparasitic infection. Seasonality related to hosts feeding habit,immunological alterations, availability of infected intermediatehosts, hormonal changes, and temperature are the most frequentcauses suggested for seasonal fluctuation in prevalence andabundance of parasitic infections (Hynes, 1950; Chappell, 1969and Pennycuick, 1971), (Table. 1, 2, &3).

Seasonal fluctuation in parasites of the present studymay be due to the temperature changes, availability ofintermediate hosts and host’s feeding habits whichcorroborated with the above findings.

Statical analysis for seasonal distribution of parasites: Thestatistical analysis revealed that the winter was the mostfavorable season for the occurrence of the parasites. Theprevalence of parasites in winter season vary significantly(P<0.01, df=2) with summer and monsoon season but therewas no significant differences (P>0.01, df=2) in theprevalence pattern of the parasites during summer andmonsoon. (Table. 4)


REFERENCESAhmed, A. ALI and Samad,S.M.K A., (1991) Probable cause of fish culture in Bangladesh. Nutrition news. 14(1): 3.Ahmed, A.T.A., (1976). Trichodiniasis of gold fish and other carps. Bangladesh J. Zool. 4(1):12-20.Arthur J.R. and Lom, J., (1984). Trichodinid protozoa (Ciliophora: Peritricha) from freshwater fishes of Rybinsk Reservoir,

USSR. J. Protozool. 31: 82–91.Awachie, J. B. E., (1966). The development and life history of Echinorhynchus truttae Schrank, 1788 (Acanthocephala). J.

Helminthol. 40 :11-32.Bauer, O.N., Musselius, V.A. and Strelkov, Yu. A., (1969). Diseases of Pond Fishes. Publisher “Kolos” Moskva. In English:

Israel Program for Scientific Translations, Jerusalem.Chappell, L. H., (1969). The parasites of the three spined stickleback Gasterosteus aculeatus L. from a Yorkshire pond. II.

Variation of the parasite fauna with sex and size of fish. J. Fish. Bio. 1: 339-347.Davidov, O.N., (1978). Growth development and fecundity of Bothriocephalus gowkongensis (Jeh, 1955), a cyprinid parasite.

Hydrobiological J. 14: 60–66.Dogiel, V. A., (1961a). Ecology of the parasites of freshwater fishes. In: Dogiel, V. A.; Petrushevski, G. K. & Polyanski, Yu.

I. (Eds.) Parasitology of fishes (Engl. Transl.). Oliver & Boyd Ltd., Edinburgh & London. pp.1-47.Dogiel, V.A., (1961b). Ecology of the parasites of freshwater fish in parasitology of fishes. Oliver and Boyd, London. pp. 1-47.Dujin, C.V.F., (1973). Diseases of Fishes. 3rd Ed., I, Life Books, London. pp- 110Durborow, Robert, M., (2003). Protozoan parasites in southern regional aquaculture centre 0ctober 2003, publication No. 4701.Eisa, M.E., El-Shazly, S.O. and Rizk, M.H., (1985). A Contribution to the pathological changes of ectoparasite trichodinids-

affected salt water fish (Grey Mullet fingerlings) in Raswa fish farm. J. Egypt. Vet. Med. 45: 107-113.Eissa, I.A.M., (2002). Parasitic fish diseases in Egypt, Ist edition, Dar El-Nahdda El-Arabia publishing. pp. 52-53.El-Khatib, N.R.H., (1989). Some studies on ectoparasitic infestation in fresh water fishes. M.V. Thesis, Cairo University

George, P.V. and Nadakal, A.M., (1973). Studies on the life cycle of Pallisentis nagpurensis Bhalerao, 1931(Pallisentidae; Acanthocephala) parasitic in the fish Ophiocephalus striatus (Bloch). Hydrobiol. 42: 31–43.

Hassan, M.A.H., (1992). Studies on some parasitic affections in fresh water fishes in Beni-Suef Governorate. P.D.V.Sc.Thesis, Cairo University.

Hoffman G.L., Kazubski S.L., Mitchell, A.J. and Smith, C.E .,(1979). Chilodonella hexasticha (Kiernik, 1909) (Protozoa,Ciliata) from North American warmwater fish. J. Fish Dis. 2 : 153- 157.

Hoffman, G.L., (1978). Ciliates of freshwater fishes. In: Kreier, J.P. (ed.) Parasitic Protozoa, II. pp. 584–632.Hoffman, G.L.,(1980). Asian tapeworm, Bothriocephalus acheilognathi Yamaguti, 1934, in North America. Fisch und Umvelt,

Special volume in honor of Prof. Dr H.-H. Reichenbach -Klinke 65th Birthday. 8: 69–75.Hossain, M.D., Hossain, M.K., Rahaman, M.H., Akter, A.and Khanom, D.A., (2008).Prevalence of ectoparasites of carp

fingerlings at Santaher, Bogra. Univ J Zool Rajshahi Univ.27: 17–19.Hynes, H. B. N., (1950). The food of freshwater sticklebacks (Gasterostaus aculeatus and Pygosteus pungitius), with a

review of methods used in studies of the food fishes. J. Anim. Ecol. 19 : 36-58

TABLE 4: ANOVA for occurrence of parasites in different seasons

Host Source sum of Degree of Mean sum of F-calculated P valuesquares( SS) freedom (df) squares (MS)

SEASON 2137.79 2 1068.90 5.88 0.00 **Hypopthalmicthys molitrix Error 14735.58 81 181.92

Total 16873.37 83 SEASON 1783.91 2 891.96 3.57 0.03 *

Cyprinus carpio Error 20235.24 81 249.82 Total 22019.15 83

SEASON 1763.63 2 881.82 4.05 0.02 *Ctenopharyngodon idella Error 20251.06 93 217.75

Total 22014.69 95 *P<0.05, **P<0.01


Kahl, A., (1935). Urtiere oder Protozoa. I. Wimpertiere oder Ciliata (Infusoria). Eine Bearbeitung der freilebnden undectocommensalen Infusorien der Erde, unter Ausschluss der Tintinnidae. 4. Peritrichida und Chonotricha. TierweltDeutchlands (Dahl). Teil .30: 651-886.

Kim, K. H., Ahn, K. J. and Kim, C. S., (2001). Seasonal abundances of Prosomicrocotyla gotoi (Monogenea) and Opecoelussphaericus (Digenea) from greenlings Hexagrammos otakii in a southern coastal area in Korea. Aquacult. 192 :147-153.

Lom, J. ,(1966). Sessiline peritrichs from the surface of some freshwater fishes. Folia Parasitol. 13: 36-56.McArdle, J.F., (1984). Trichodina as cause of mortalities in cage reared Rainbow trout and Salmon. Bull. Eurp. Ass. Fish.

Pathol, 4: 3-6Migala, K. and Kazubski, S.L., (1972). Occurrance of nonspecific ciliates on carps (Cyprinus carpio L.) in winter ponds.

Acta protozool. 8: 309-339.Min, H.K.., (1982). Study on helminthic zoonoses in Korea. Yonsei Rep Trop Med. 13: 41-58.Mohan, C.V., (2003). Species introductions: Impacts on aquatic animal health and trade. Presentation at the Aquamarkets

Shrimp Session, Manila, Philippines, June 2–6,Paperna, I. and Van As J.G., (1983). Epizootiology and pathology of Chilodonella hexasticha (Kiernik, 1909) (Protozoa,

Ciliata) infections in cultured cichlid fishes. J. Fish Biol.23:441–450.Pennycuick, L., (1971). Seasonal variations in the parasite infections in a population of three spined sticklebacks, Gasterosteus

aculeatus L. Parasitol. 63 : 373-388.Rim, H.J., (1997). Epidemiology and control of clonorchiasis in Korea. In: Waikagul J, Cross JH, Supavej S, eds. Proceedings

of the 2nd seminar on food-borne parasitic zoonoses: current problems, epidemiology, food safety and control.Southeast Asian J Trop Med Public Health, 28(suppl 1) : 47-50

Rogers, W. A., (1971). Disease in fish due to the protozoan Epistylis (Ciliata: Peritricha) in the Southeastern U.S., Proc. 25thAnn. Conf. Southeastern Assoc. Game and Fish Comm. 25: 493-496.

Sarig, S., (1968a). Possibilities of prophylaxis and control of ectoparasities under condition of intensive warm water fishculture. Bull. of. Epiz. 69(9-10): 1577-1590.

Schaperclaus, W., (1954). Prevention of infectious abnormal dropsy in common carp by inoculation and treatment withdrugs, DFZ, 1: 102-108

Scheubel J., (1973). Die sessilen Ciliaten unserer Süsswasserfischen unter besonderer Berücksichtigung der Gattung ApiosomaBlanchard. Zool. Jb. Syst. 100: 1–63.

Shulman, S. S., (1957). Note sur la pathogenesis de la Myxosporidie Myxobolus exiguus et sur les epizootics dues a parasite. Bull. Inst. Rech. 42: 1-328 (in Russian)

Soota, T. D., (1980). Collection and preservation of trematodes and cestodes. Proc. Workshop Tech. Parasitol. Zool. Surv.India. pp. 27-29.

Soulsby, E. J. L., (1982). Helminths. In :Soulsby, E. J. L. Helminths, Arthropods and protozoa of domesticated animals.Seventh edition. The English language book Soc. and Bailliere Tindall. London. pp. 5-354.

Srivastava, C. B.,(1980). Estimation of helminthic infections. Proc. Workshop Tech. Parasitol. Zool. Surv. India. pp. 29-31Tatcher, V.E., (1981). Patologia de peixes da Amazonia brasileira, 1. Aspectos gerais. Acta Amazonica. 11: 125-140.Tweb, A. and Ahmed, A., (1981). Helminth infection in freshwater fishes of Bangladesh. Fish Pathol. 15(3/4) : 229-236Wisheiwski, W. L., (1958). Characterization of the parasite fauna of an Eutrophic lake. Actoparasitol. Pol. 6: 1-64.

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