Prevalence of Porcine Cysticercosis in Nagaon, Morigaon and Karbianglong District of Assam, India

Prevalence of Porcine Cysticercosis in three districts of Assam was studied for a period of one year from March 2002 to February 2003. Except certain geographical region of Assam, many districts of this state have yet remained unexplored for this important zoonotic disease, let along the following three districts i.e. Nagaon, Morigaon and KarbiAnglong. Monthly visit to the market places were made in different localities of the three districts. Prevalence of cysticercosis according to age, sex, breed of carcasses and seasonal occurrence were studied. The whole period of observation was divided in to four seasons as per Indian Meteorological Department as pre-monsoon, monsoon, post-monsoon and winter. A total of 978 pigs were examined, out of which 93 pigs (9.50%) were found to be positive for infection. District wise highest (13.70%) prevalence was found in KarbiAnglong and lowest (7.55%) in Nagaon district. Age wise prevalence study showed highest (11.41%) in the age group of 7-12 months and lowest (7.60%) in the age group 19-24 months. Prevalence of C. cellulosae infection in male and female was 9.15 and 10. 39 percent respectively. Breed wise prevalence was found more in cross bred (12.53%) than in local breed (7.49%).Overall seasonal prevalence was highest during pre-monsoon (10.93%) and lowest (7.82%) during monsoon season. Though there were variation in the rate of prevalence of porcine cysticercosis based on age, sex, breed and seasons. The disease was found to exist in the study area throughout the year that ranged from 5.71 to 14.06 percent.


Introduction
Pig rearing is common in Assam.Pig rearing practices in Assam are mostly semi-intensive and Porcine cysticercosis due to Cysticercus free ranging sytem.cellulosae is a disease caused by larval stage of Cysticercosis due to C. cellulosae in pig is Taenia solium.Pig act as intermediate host for acquired due to unhygienic feed or water intake perpetuate the life cycle of C. cellulosae .Human by this animal along with the viable eggs of T. is the only natural host of adult stage of T. solium solium.In pigs, cysts are distributed in the striated which causes taeniasis, a serious parasitic muscles like heart, tongue and skeletal muscle zoonosis (WHO, 1979).Cysticercosis in humans like forearm.The cysts were also found in liver, occurs due to the ingestion of this tape worm lung, spleen, eye, conjunctiva and nervous eggs, either from external sources or from the system of pigs, which remain viable for long person's own feces.The human has then become time.Presence of cyst in the tissue is responsible an accidental and "dead-end" intermediate host for the condemnation of meat, thus economic (that is, the infection can not progress any losses to the pig producer.The prevalence of this further.(Markell et. al. 1999).Pigs, which are the metacestode is therefore taken considerable "normal" intermediate host for this parasite, get importance and a study was conducted to explore infected with cysticerci when they ingest human the incidence of this parasite in market pork feces.
brought for human consumption.
positive out of 138,) found in the age group 7-12 months and the lowest infection 6.89% in 1-6

Materials and Methods
months (2 out of 29).Percentage of infection in Epidemiological studies of porcine cysticercosis male pig was found 8.24% (24 out of 291) and in was conducted in Nagaon, Morigaon and female 8.08 % (8 out of 99 female pigs).Breed Karbianglong district of Assam for a period of wise prevalence study showed out of 215 one year starting from the month of March 2002 crossbred pigs examined, 21 (9.76%) and out of to February 2003.The study areas were a 175 local pigs examined, 11(6.28%).Prevalence representative of urban, semi-urban and rural of infection was highest 10.11% during the predistrict of Assam, the northeastern part of India.monsoon season (out of 89, 9 were found to be Good numbers of pork were marketed in these positive) and lowest infection 6.92% during the districts of the state.Monthly visit to the market monsoon season (out of 130, 9 were found to be places were made in different localities of the positive).three districts of Assam.Pig carcasses brought for In KarbiAnglong district, prevalence of human consumption in the market were examined Cysticercosis was studied on 270 numbers of as per the method of Thronton and Gracy (1974) pigs, out of which 37(13.7%) were found to be for presence of C. cellulosae.Age, sex and breed positive.Age wise prevalence showed highest of the carcasses were recorded.Animal were infection (16.00%) was found in the age group of divided in to different age groups i.e. 1-6, 7-12, 13-18 months (Out of 50 pigs examined, 8 were 13-18 and 19-24 months of age.Seasonal prevalence found to be positive).Lowest infection recorded of porcine cysticercosis was also recorded.The 8.33% in 19-24 months of age i.e. out of 60 pigs examined 5 were found to be positive.Examination whole period of observation were divided in to of 128 male and 142 female pigs showed four seasons i.e. pre-monsoon (March, April and May), monsoon (June, July, August and September), 18(14.06%)and 19(13.38%)nos positive for cysticercosis.Breed wise prevalence study post-monsoon (October and November) and showed a total of 130 local pigs were examined, winter season (December, January and February).
out of which 12(9.23%) and out of 140 crossbred

Results
animals examined, 25(17.85%).Seasonal prevalence of infection showed highest infection A total of 978 pigs were examined for 21.62% was found during the winter season i.e. cysticercosis, out of which 93(9.5%) were found out of 37 pigs examined, 8 were found to be to be positive found to be positive and lowest infection 7.60% showed a total of 282 local pig examined, out of which 21 (7.44%) were found positive and out of in the age group19-24 months of age i.e. out of 36 cross bred pig examined, 3 (8.33%)were 171 pigs examined, 13 were found to be positive.found positive.In the same district, highest Overall sex wise prevalence irrespective of 3 infection (10.76%) was found during the predistricts has been summarized in Table-2.Out of monsoon season.
total 699 male pigs examined, 64 (9.15%) found In Morigaon district, a total of 390 pigs was to be positive and out of a total 279 female pigs examined, out of which 32 (8.2%) were found to examined, 29(10.39%)were found to be positive.be positive.The highest infection 8.69% (12 Overall breed wise prevalence irrespective of 3 districts has been summarized in Table - This finding might be due to breed predisposition, which requires further detail was from 2-4 weeks of age.
studies.In Morigaon district, it was noted that Pigs reared in the present study area were let good proportion of crossbred pigs were regularly loose and had free access to contaminated areas brought to the market from outside of the from where they acquired the infection.
state of NE-region who might harbouring the Therefore the finding implies that there was a infection and also contributing to the already continuous level of infection in environ-ment in existing disease situation in the study area.This which the animals are regularly exposed to contention could be substantiated by the high infection.Aluja and Vargas (1988) classified prevalence rate of porcine cysticercosis in the histological lesions according to the severity of contiguous states (Kumar and Gaur 1994).In the tissue inflammatory response, larval degenepresent study, overall seasonal record was found ration and replacement by scar tissue in porcine highest infection during pre-monsoon season cysticercosis.They were of the opinion that, (10.935) and lowest (7.82%) during monsoon greater number of degenerated larvae might season.(Table -4) which was not agreement with occur in older pigs, many of which are acquired the finding of Deka (1989) who recorded highest during early stage of life.In the present study, it infection in Autumn (5.10%) and lowest (2.65%) was rather difficult to ascertain at which age the in winter, but was in agreement with D,Souza infection was picked up to what proportion the (1998) who recorded higher infection during the cysts were degenerated in older age in natural summer (March to May)than the winter season cases.In present study areas maximum number of (January to February).This finding might be due animals was brought to the market within the age to geographical variation in all three study areas group of 7-12 months of age, therefore these age under reference.groups considered as high-risk group of animal in It was interesting to note that, though there comparison to other three groups which may give was fluctuation of infection in all the three infection to human being.Further young pigs are different districts of the study area, it showed that, preferred more by the consumers, which were the entire study area was highly endemic for found to be more delicious and used for small porcine cysticercosis and may be sources of community gatherings and festivals that might infection to human taeniasis in local population.act as source of infection to human being.In the present study, sex wise overall prevalence of porcine cysticercosis was found to be higher in Authors are highly thankful to Dean, College females (10.39%) than in males(9.15%).Earlier, of Veterinary Sciences, Khanapara, Guwahati for Deka(1989), Plain(1991) and DevSarma (1999) providing necessary facilities to carry out the also recorded similar result, which was in study.The work was supported in the form of agreement with the present findings.
financial grant by Indian Council of Agricultural Higher prevalence in females in present study Research, New Delhi under the sponsored might be due to the natural feeding behaviors of Research Project.females with their litters who use to loiter in and Conflict of interest around human habitats in search of garbage and generally avoid conflict with their aggressive Authors declare that they have no conflict of male counterparts.Similar observations were interest.

No. animal No.positive No. animal No. positive No. animal No. positive No. animal No. positive
3. A of Assam i.e.Nagaon, Morigaon and Karbi Anglong total of 587 local pigs examined, 44(7.49%)from March 2002 to February 2003.

Table - 2: Sex wise overall prevalence of C.cellulosae in pigs from March2002 to February 2003
*Figure in the parenthesis indicate percentage

Table - 3: Breed wise overall prevalence of C. cellulosae in pigs from March 2002 to February 2003
*Figure in the parenthesis indicate percentage

Table - 4: Overall seasonal prevalence of C.cellulosae in pigs from March 2002 to February 2003
Aluja et.al.(1998)thesisindicatepercentageas referred above and establishes the fact that, the also made byAluja et.al.(1998).Breed wise present study areas were endemic for porcine overall prevalence of porcine cysticercosis in the cysticercosis.In the present study age wise present study was found to be more in cross bred prevalence of porcine cysticercosis was found to (12.53%) than in local bred (7.49%) pigs.(Tablehighest(11.41%) in the age group of 7-12 months 3).Previously Pramanik et.al .(1985)and Deka and Gaur (1990) could also recorded higher and lowest (7.60%) in 19-24 months of age.Aluja infection in crossbred than in indigenous animals.et.al. (1998) recorded the earliest age of piglets who get infected in rural community in Mexico *