DYNAMICS OF GASTROINTESTINAL PARASITIC INFECTIONS AND PREDICTION OF HAEMONCHUS CONTORTUS

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1 Indian J. Anim. Res., () : -1, 1 AGRICULTURAL RESEARCH COMMUNICATION CENTRE / indianjournals.com SEASONAL DYNAMICS OF GASTROINTESTINAL PARASITIC INFECTIONS AND PREDICTION OF HAEMONCHUS CONTORTUS INFECTIONS OF GOATS IN A SUBTROPICAL HILLY REGION OF NORTH-EASTERN INDIA R. Laha*, M. Das and A. Goswami Division of Veterinary Parasitology ICAR Research Complex for NEH Region Umroi Road, Umiam, Meghalaya 1, India Received: 1--1 Accepted: 1--1 A B S T R A C T A study on seasonal prevalence of gastrointestinal parasitic infections in goats maintained in a subtropical hilly region of North Eastern India was undertaken for a period of two years. Gastro intestinal parasites have been found to occur through out the year. The overall prevalence of gastrointestinal parasitism was recorded as 6.6%. Separately,.% and.% infections were recorded during the year and 1, respectively. Over all the eggs of Strongyle species (6.%), Strongyloides spp. (1.6%), Trichuris spp. (.6%), Moniezia spp. (1.%) and oocysts of Eimeria spp. (16.%), were detected in faecal samples of goats. Over all the higher prevalence was recorded during rainy season (6.%) followed by cool season (.66%), summer season (6.%) and cold season (.%). Higher eggs per gram of faeces (EPG) were observed during monsoon only. Coproculture of goat faecal samples revealed the presence of Haemonchus contortus (.16%), Oesophagostomum spp. (1.6 %), Strongyloides spp. (6.%) and Trichostrongylus spp. (.%) larvae. The prediction or forecasting of H. contortus infection in this goat farm as per bioclimatographs for these two years revealed a prediction of H. contortus infection in goats from April to September in this agroclimatic zone. Keywords : Gastrointestinal parasites, Goat, Haemonchus contortus, Prediction, Subtropical Hill. INTRODUCTION Gastrointestinal parasitic infections in goats are major constraints in small ruminant s production system. Gastrointestinal parasitism is an important cause of death in goats (Valentine et al., ). Both experimental and natural infections found to have economic importance (Gwaze et al., ; Rahman, 1; Sharma et al., ; Faizal et al., 1). Environmental factors play a vital role in the parasitic infections and prevalence rate of infections may vary (Sharma et al., ). For controlling gastrointestinal parasitism, information about the epizootiology of gastrointestinal parasites on a regional basis is important. H ence, in the present study the prevalence of gastrointestinal parasitism in relation to season in goats maintained in a subtropical hilly region is being reported, as such type of detailed study from this agroclimatic zone is not available. Among the gastrointestinal nematode infections in goats, Haemonchus contortus has been found predominant throughout the world and also found as most pathogenic nematode (Dorny et al., 1; Sharma et al, ; Dey et al., ; Gadahi et al., ; Jas et al., ; Pant et al., ). To chalk out the control programme and to prevent the initiation of anthelmintic resistant parasites, it is essential to know well in advance regarding the prevalence of infection. Hence, in the present study an attempt has been made to predict the H. contortus infection in this subtropical hilly region based on a two year study, as such type of study has not done in this subtropical hilly region earlier. MATERIALS AND METHODS The goats maintained in the goat farm of ICAR Research Complex for NEH Region, Umiam, Meghalaya, India were studied for a period of years. This farm is situated at an altitude of about * Corresponding author s rglaha@gmail.com

2 1 INDIAN JOURNAL OF ANIMAL RESEARCH m above mean sea level where average monthly minimum and maximum temperature were observed as 6.1 C and. C, respectively, during the study period. The average monthly relative humidity prevailed during the study period were recorded as 6.% (minimum) to 1.% (maximum) with average annual total rain fall 1. mm. These goats are maintained in semi-intensive system and the pasture land for these goats constitutes mainly native grasses. Climatic condition of the farm area like temperature, rainfall and relative humidity were recorded at the Institute Meteorological Station located within the Institute Campus and the required meteorological data like average minimum and maximum temperature, relative humidity and rainfall were taken from this station every month. A total of 6 numbers and 66 numbers of faecal samples of goats were collected during the year and 1 respectively, to know the seasonal prevalence of gastrointestinal parasitism. Rectal faecal samples from these goats were collected manually in suitable containers and labeled carefully and these faecal samples were examined to know the presence of nematode eggs and coccidian oocysts. The eggs per gram of faeces (EPG) for nematodes were estimated by the modified McMaster techniques. Gastrointestinal nematode larvae were identified after culture of the pooled faecal samples in B.O.D. at C for days. For prediction or forecasting of H. contortus infection in this goat farm, studies for these two years were under taken. Bioclimatographs were prepared for prediction of H. contortus infection as per methods described by Swarnkar and Singh (11). In brief, bioclimatographs for each year separately were prepared in which average monthly total rainfall (TRF) or relative humidity (RH) of a particular month was plotted against the maximum temperature (T_max) or minimum temperature (T_min) for the months and the resultant points are joined by a closed curve. The months were marked numerically like 1,, etc. represented the month January, February, etc. respectively. A window indicating the limit of the climatic conditions most suitable for development and survival of exogenous stages of H. contortus was prepared and superimposed within this bioclimatograph. The limits of suitable climatic conditions were taken as total monthly rainfall more than mm, relative humidity more than % with average monthly maximum temperature ranging from 1- o C. The resultant bioclimatographs were compared with the real time incidence of the H. contortus infections as observed after faecal larval culture. The real time incidence of the H. contortus infections was estimated by collection of faecal samples of goats every month for a period of two years and culture of larvae as per methods mentioned above. Meteorological data like average minimum and maximum temperature, total rainfall and relative humidity of every month were collected as mentioned above. RESULTS AND DISCUSSION The results of monthly examination of faecal samples and percentage of infection found positive for gastrointestinal parasitic infections along with mean EPG for the year and 1 are presented in Table 1 and Table, respectively. The overall prevalence of gastrointestinal parasitism was recorded as 6.6%. Separately,.% and.% infections were recorded during the year and 1 respectively. Over all the eggs of Strongyle species (6.%), Strongyloides spp. (1.6%), Trichuris spp. (.6%), Moniezia spp. (1.%) and oocysts of Eimeria spp. (16.%), were detected in faecal samples of goats. Mixed infections were also observed. Month wise correlations between metrological parameters with percentage of infection and EPG have been depicted in Table 1 and. It could be observed from these tables that there is an increase trend of percent prevalence of gastrointestinal parasitism from the month of January which reached its peak in the month of July and then it declined for both the years. As per EPG is concerned, during the year, EPG count reached its peak in the month of June, dropped in the month of July, then increased up to the month of September and then declined. There is an increase trend of EPG count from the month of January which reached its peak in the month of July and then it declined during the year 1. If we look into the meteorological parameters, then it could be observed that the temperature and humidity favourable for exogenous development of gastro-intestinal parasites are present through out the year in this agroclimatic

3 Vol., No., 1 11 TABLE 1: Monthly prevalence of gastrointestinal parasites in goats and meteorological data during the year. Month Nos. of Samples No. positive Mean FEC* T_min T_max TRF RH examined (%) ( C) ( C) (mm) (%) January 6 (6.) February (.1) March (.) April 1 (.) May 1 (.) June 16 (.) July (.) August 1 (6.1) September 1 (6.) October 1 (.) November (6.6) December 6(.) Total 6 1(.). *FEC = Faecal Egg Count zone. Where there is a lack of total rainfall, high percentage of relative humidity could have played a role to provide sufficient moisture for exogenous hatching and larval development. These may be the reason for presence of gastrointestinal parasites through out the year. The state Meghalaya has four distinct seasons i.e. the rainy season from May to early October, the co ol season f rom early Octo ber to November, the cold season from December to February and the warm season or hot season from March to April ( meghalaya/weather.htm), unlike most of the states of India, where three seasons li ke summer, rainy and winter have been observed. In that respect, over all the higher prevalence was recorded during rainy season (6.%) followed by cool season (.66%), summer season (6.%) and cold season (.%) and more EPG was observed during monsoon only. TABLE : Monthly prevalence of gastrointestinal parasites in goats and meteorological data during the year 1. Month Nos. of Sample No. positive Mean FEC* T_min T_max TRF RH examined (%) ( C) ( C) (mm) (%) January (16.6) February 6 1 (.6).... March 1 (1.) April (6.6) May 6 6 (6.) June (.) July (.) August (6.) September (.) October 6 (1.) November 1 (1.) December 1 (.).... Total 66 (.). *FEC = Faecal Egg Count

4 1 INDIAN JOURNAL OF ANIMAL RESEARCH TABLE : Comparative prediction of bioclimatographs of H. contortus in goats. 1 Favourable Observed Favourable Observed Months months for Months months for Parameters of predicted by higher predicted by higher Bioclimatograph bioclimatograph incidence bioclimatograph incidence of H. of H. contortus contortus T_max v/s TRF March- Nov April-Sept March-Sept May-Sept. RH v/s T_max Jan - Dec April-Sept Jan-Dec. May-Sept. RH v/s T_min May - Sept. April-Sept. April-Aug. May-Sept. TRF v/s T_min June - Sept. April-Sept. June- Sept. May-Sept The infection rate in this agroclimatic zone was found less in comparison to other parts of the country (Pathak and Pal, ). Seasonal prevalence of gastrointestinal parasitic infection in goats as highest in monsoon (.6%), moderate in summer (.%) and lowest in winter (6.1%) with overall prevalence of.% observed by them. Besides, seasonal prevalence of gastrointestinal nematode infection from India as highest in rainy season (6.%) followed by summer (.%) and winter (1.%) reported by Sharma et al. (). Higher prevalence of gastrointestinal parasites during rainy season as observed in the present study although supported by other workers, but this agroclimatic region has more time period for rainy season and thus needs special care to monitor and control gastrointestinal parasitism in goats, in comparison to other parts of the country. Similar to the present findings, maximum egg counts during wettest period of the year have been observed by Dorny et al. (1). In temperate agroclimatic zone of India, maximum gastrointestinal nematode infection has been observed during summer season and H. contortus has been recorded as highest prevalent species (Tariq et al., 1). An increase count of strongyle types of eggs in goats with increased rain observed that reached highest in the peak of the rainy season (Nwosu et al., ). Coproculture of goat faecal samples revealed the presence of H. contortus (.16%), Oesophagostomum spp. (1.6 %), Strongyloides spp. (6.%) and Trichostrongylus spp. (.%) larvae. After faecal culture, H. contortus has been found predominant species in goats of India (Sharma et al., ; Pant et al., ; Dey et al., ). Dorny et al. (1) also reported H. contortus, Trichostrongylus spp. and Oesophagostomum spp.as most prevalent species of nematodes in goats. The bioclimatograph for prediction of H. contortus for the year and 1 have been presented in Fig. 1, Fig. and Table. The favourable months predicted by bioclimatographs were March to November; January to December; May to September and June to September when plotted against T_max v/s TRF, RH v/s T_max, RH v/s T_min and TRF v/s T_min respectively, for the year. In case of year 1, the favourable months predicted by bioclimatographs were March to September, January to December, April to August and June to September. The observed months for higher incidence of H. contortus were April to September for the year and May to September for the year 1. Thus for this agroclimatic zone we can predict H. contortus infection from April to September. The role of bioclimatographs in forecasting of strongyle infection particularly H. contortus infection in sheep in India (Rajasthan) was reported by Swarnkar and Singh (11). There is no such report from goats from India particularly from a subtropical hilly area. Swarnkar and Singh

5 Vol., No., 1 1 T _ m a x (C ) T R F v s T _ m a x T _ m in 1 T R F v s T _ m i n T _ m in 1 R H v s T _ m i n 6 R H 6 1 T _ m a x 1 R H v s T _ m a x 6 R H 6 1 FIG.1: Bioclimatographs for Haemonchus contortus for the year. RH = Relative Humidity; T_min= Temperature Minimum ; T_max = Temperature Maximum; TRF = Total Rain Fall; 1 to 1 stands for month like 1 = January and 1= December 1 T R F v s T _ m i n - T _ m i n 6 T _ m a x T R F v s T _ m a x T _ m a x 1 R H v s T _ m a x 6 R H ( % ) 6 1 T _ m in 1 R H v s T _ m i n R H ( % ) 6 FIG.: Bioclimatographs for Haemonchus contortus for the year 1 RH = Relative Humidity; T_min= Temperature Minimum ; T_max = Temperature Maximum; TRF = Total Rain Fall; 1 to 1 stands for months like 1 = January and 1= December

6 1 INDIAN JOURNAL OF ANIMAL RESEARCH (11) observed June to mid-september and late June to mid-august in semi-arid and arid zones of India respectively, are suitable for development, survival and dissemination of exogenous stages of H. contortus. Their observations on real time incidence was fully in agreement with prediction by bioclimatographs on long- term basis, but minor variation on real time incidence with predicted months by bioclimatographs on annual basis observed by them. In the present study slight variations in predicted months observed by bioclimatographs, which is due to climatic variations of two years. Within similar agroclimatic region, slight to moderate variation in prediction have been observed by Swarnkar and Singh (11). Although EPG was observed throughout the year but more EPG as well as larval culture indicated H. contortus observed from April to September. Thus for this agroclimatic zone we can predict H. contortus infection from April to September. This prediction is differing from the study done other parts of India due to variation of climatic condition in this agroclimatic zone. ACKNOWLEDGEMENTS The authors are thankful to I ndi an Council of Agricultural Research, New Delhi to carry out this research work under All India Network Programme on Gastroi ntesti nal Parasitism. The facilities provided by Director, ICAR Research Complex for NEH Regi on, Umi am, Meghalaya, Indi a, are thankfully acknowledged. REFERENCES Dey, S., Sanyal, P.K., Mukherjee, K., Sarkar, A.K., Patel, N.K., Mandal, S.C. and Pal, S. (). Caprine parasitic gastroenteritis in semi-organized farming conditions. J.Vet. Parasitol., : -. Dorny, P., Symoens, C., Jalila, A., Vercruysse, J. and Sanib, R.(1). Strongyle infections in sheep and goats under the traditional husbandry system in peninsular Malaysia. Vet. Parasitol.,6 : Faizal, A. C. M., Rajapkshe, R. P. V. J.,Jayasinghe, S. R. and Rupasinghe, V. (1). Prevalence of Eimeria and gastrointestinalnematodes vs weight gains in treated goats in thedry areas of Sri Lanka. Small Rumin. Res., :1-. Gadahi, J.A., Arshed, M. J., Ali, Q., Javaid, S. B. and Shah, S. I. (). Prevalence of Gastrointestinal Parasites of Sheep and Goat in and around Rawalpindi and Islamabad, Pakistan. Vet. World, : 1-. Gwaze, F. R., Chimonyo, M. and Dzama, K. (). Prevalence and loads of gastrointestinal parasites of goats in the communal areas of the Eastern Cape Province of South Africa. Small Rumin. Res., : 1 1. Jas, R., Datta, S. and Ghosh, J.D. (). Haemato-biochemical impact of gastrointestinal nematodosis in Bengal goat. J. Vet. Parasitol., : 1-6. Nwosu, C.O., Madu, P.P. and Richards, W.S. (). Prevalence and seasonal changes in the population of gastrointestinal nematodes of small ruminants in the semi-arid zone of north-eastern Nigeria. Vet. Parasitol., 1: Pant, K., Rajput, M.K.S., Kumar, J., Sahu, S., Rajkumari,V. and Gangwar, P. (). Prevalence of helminthes in small ruminants in Tarai region of Uttarakhand. Vet. World, : Pathak, A. K. and Pal, S. (). Seasonal Prevalence of Gastrointestinal Parasites in Goats from Durg District of Chhattisgarh. Vet. World, 1:16-1. Rahman, W.A. (1). Effect of sub clinical Eimeria species infections in tropical goats subsequently challenged with caprine Haemonchus contortus. Vet. Rec., 1: -. Sharma, D.K., Chauhan, P.P.S. and Agrawal, R.D. (). Interaction between Trypanosoma evansi and Haemonchus contortus infection in goats. Vet. Parasitol., : Sharma, D.K., Agrawal.N., Mandal, A., Nigam, P. and Bhusan, S. (). Coccidia and gastrointestinal nematode infections in semi-intensively managed Jakhrana goats of semi-arid region of India. Trop. Subtrop. Agroecosystems., 11: 1-1. Swarnkar, C.P. and Singh, D.K.(11). Role of bioclimatographs in forecasting of strongyle infection in Rajasthan. Indian J. Anim. Sci., 1: 16. Tariq, K.A., Chishti, M.Z. and Ahmad, F. (1). Gastro-intestinal nematode infections in goats relative to season, host sex and age from the Kashmir valley, India. J. Helminthol., :-. Valentine, B.A., Cebra, C.K. and Taylor, G.H. (). Fatal gastrointestinal parasitism in goats: 1 cases (1-6). J. Am. Vet. Med. Assoc., 1:1-11.