VOLUME 1 NO. 1 JULY 2010 • pages 37-44 MALAYSIAN JOURNAL OF VETERINARY RESEARCH

PREVALENCE OF HELMINTHIASIS IN RELATION TO CLIMATE IN SMALL RUMINANTS IN IN 1998 AND 2008

NORAKMAR I., CHANDRAWATHANI P., NURULAINI R., ZAWIDA Z., PREMAALATHA B., IMELDA LYNN V., ADNAN M., JAMNAH O. AND ZAINI C.M. Veterinary Research Institute, Department of Veterinary Services, 59 Jalan Sultan Azlan Shah, 31400 , Perak. Corresponding author: [email protected]

ABSTRACT. This is a prevalence study of districts in Perak. Comparison between the correlation, pattern and comparison of data in 1998 and 2008 showed higher helminthiasis cases in small ruminants in number of helminthiasis in 2008, which relation to the weather conditions in Perak may be due to higher population of small in the year of 1998 and 2008. Helminthiasis ruminants in that year. Therefore, further is annually diagnosed at the Parasitology research should be conducted to investigate Unit of VRI. Due to the global warming thoroughly the relationship and the effect and climate changes, there is a need to of weather on helminthiasis. Anthelmintic know the effects of weather, if any, on resistance study is also conducted to help the increasing trend of helminthiasis farmers reduce helminthiasis problems in cases diagnosed in the districts of Perak. the farms. The methods applied for the diagnosis of Keywords: Helminthiasis, small helminth in faecal samples from sheep and ruminants, weather, rainfall, FEC goats were McMaster, fl oatation and larvae culture methods. In this study, animals with INTRODUCTION faecal egg counts (FEC) of 500 e.p.g and above are considered as positive helminth Helminthiasis is considered as one of cases. Rainfall data is correlated to the the most prominent causes of mortality farm location in each district and further in small ruminants. The most common analysed according to parasitological helminth infection is caused by the status. Generally, humidity and rainfall are Trichostrongyloidea family, namely high throughout the year, however, further Haemonchus contortus. This is a analysis of data does not show signifi cant bloodsucking parasite which causes correlation between helminthiasis and nutrient defi ciency in small ruminants rainfall in the state. High humidity leading to mortality. The current emerging conditions contribute to the survival of problems of anthelmintic resistance infective larval stage of helminths such as in small ruminants causes severe Haemonchus contortus and this may be the repercussions by reducing productivity. cause for high helminthiasis cases in some Epidemiological studies describe that

37 MALAYSIAN JOURNAL OF VETERINARY RESEARCH VOLUME 1 NO. 1 JULY 2010

the lower environmental limits for loss caused by parasites (Morgan and Wall, haemonchosis to infect small ruminants 2009). is having a monthly mean temperature of Looking at previous research, there 18⁰C and approximately 50 mm rainfall, is some correlation between the high thus it has been generally recognized prevalence of Haemonchus contortus that Haemonchus contortus is a parasitic with weather conditions found in other problem to the warm and wet countries countries with almost similar climate where small ruminants are reared (Waller conditions as . The research and Chandrawathani, 2005). recorded peak infection level during rainy The hatching of eggs and survival of season and low infection levels during dry the infective stage larvae depends on two season (Chaudry et al., 2007). This study most important components of the external was conducted to observe and correlate the environment, which is the temperature trends of climate change in 1998 and 2008 and humidity. The optimal temperature and the effect of the climate change to the for the development of the maximum prevalence of helminthiasis in the districts number of larvae in the shortest feasible of Perak in the year 1998 and 2008. time is generally in the range 18-26°C (Taylor et al., 2007). The optimal humidity MATERIALS AND METHODS is 100% although some development can occur down to 80% relative humidity, In this study, data of positive helminthiasis however, even in dry weather where the cases received in the Parasitology ambient humidity is low, the microclimate and Haematology Unit of Veterinary in faeces or at the soil surface may be Research Institute (VRI) for the state suffi ciently humid to permit continual of Perak in year 1998 and 2008 were larval development (Taylor et al., 2007). collected and compiled. These data were In the trichostrongyloids, the divided according to the 9 districts in embryonated egg and ensheathed infective Perak. Meteorological data of the annual

stage of the larvae, L3 is best equipped to temperature, humidity and rainfall in the survive in extreme condition whether it year 1998 and 2008 were gathered from be freezing or dessication. The increases the Meteorology Department of Malaysia in temperature caused by global warming from 9 meteorology stations situated in the might be expected to have major effects districts of Perak. The data include amount on the abundance of parasites population, of rainfall in millimeter (mm) collected in through higher rates of development and 24 hour period, mean relative humidity release of infective stages. This leads to in percent (%) and mean temperature in widespread assumptions that as a result of degree Celsius (°C). climate change, livestock will tend to suffer The faecal egg count (FEC) test from increasing disease and production was conducted to estimate the number of

38 VOLUME 1 NO. 1 JULY 2010 MALAYSIAN JOURNAL OF VETERINARY RESEARCH

TABLE 1. Helminthiasis Cases in the Districts of Perak in 1998 and 2008 DISTRICT 1998 2008 Kinta 134 634 Perak Tengah 19 8 47 342 Manjung 0 13 Batang Padang 0 108 Hulu Perak 7 27 Hilir Perak 10 90 Larut Matang 3 17

TABLE 2. Total rainfall (mm) in the Districts of Perak in 1998 and 2008 DISTRICT 1998 2008 Kinta 2114.8 2935.2 Perak Tengah 2044.7 2741.1 Kuala Kangsar 1834.4 2061.6 Manjung 1048.0 1098.4 Batang Padang 2849.7 3426.4 Hulu Perak 1393.2 1674.0 Hilir Perak 1628.5 1594.6 Larut Matang 3864.6 5146.0

TABLE 3. Small ruminants populations in Districts of Perak in 1998 and 2008 YEAR DISTRICT 1998 2008 Kinta 2,935 3,826 Perak Tengah 1,741 3,728 Kuala Kangsar 3,926 5,621 Manjung 4,534 6,171 Batang Padang 3,885 8,260 Hulu Perak 2,629 2,036 Hilir Perak 3,944 3,326 Larut Matang 5,918 2,545

39 MALAYSIAN JOURNAL OF VETERINARY RESEARCH VOLUME 1 NO. 1 JULY 2010

Helminth cases in the districts of Perak for 1998 and 2008

700 634

600

500

400 1998 342 2008 300

Helminth C as es 200 134 108 90 100 47 19 27 17 8 0 13 0 7 10 3 0 Kinta Perak Kuala Manjung Batang Hulu Perak Hilir Perak L arut Tengah Kangsar Padang Matang

FIGURE 1. Graph of helminth cases in the districts of Perak for 1998 and 2008

T otal rainfall (mm) v s helminth c as es and s mall ruminants population in the districts of Perak for 1998 and 2008

9,000 4000 8,260 8,000 3500 7,000 6,171 3000 6,000 5,621 5,918 2500 5,000 4,534 2000 3,826 3,926 3,885 3,944 4,000 3,728 3,326 1500 3,000 2,935 2,629 Helminth C as es 2,545 Total R ainfall (mm) 2,036 1000 2,000 1,741 634 1,000 342 500 108 90 8 13 27 17 0 0 Kinta Perak Kuala Manjung Batang Hulu Perak Hilir Perak L arut Tengah Kangsar Padang Matang

Population in 1998 Population in 2008 Helminth C ases in 1998

Helminth C ases in 2008 Total RainfallDistrict 1998 Total Rainfall 2008

FIGURE 2. Graph of small ruminants population data in the districts of Perak in 1998 and 2008

40 VOLUME 1 NO. 1 JULY 2010 MALAYSIAN JOURNAL OF VETERINARY RESEARCH

Total rainfall (mm) in the districts of Perak for 1998 and 2008

6000.0

5146.0 5000.0

4000.0 3864.6 3426.4 2935.2 1998 3000.0 2741.1 2849.7 2008 2061.6

Total R ainfall (mm) 2000.0 2114.8 1628.5 2044.7 1834.4 1674.0 1594.6 1393.2 1098.4 1000.0 1048.0

0.0 Kinta Perak Kuala Manjung Batang Hulu Perak Hilir Perak L arut Tengah Kangsar Padang Ma ta ng

FIGURE 3. Graph of total rainfall (mm) in the district of Perak for 1998 and 2008

T otal rainfall (mm) vs helminth c as es and s mall ruminants population in the districts of Perak for 1998

6,500 350 6,000 5,918 5,500 300 5,000 4,534 4,500 3,926 3,885 3,944 250 4,000 3,500 200 2,935 2,629 3,000 134 2,500 150 2,000 1,741 100 1,500 47 1,000 19 50 Helminth C as es 7 10 3 Total R ainfall (mm) 500 0 0 0 0 Kinta Perak Kuala Manjung Batang Hulu Hilir Larut Tengah Kangsar Padang Perak Perak Matang

Population in 1998 Helminth C ases in 1998 T otal R ainfall 1998

FIGURE 4. Graph of total rainfall (mm) vs helminth cases and small ruminants population in the districts of Perak in 1998

41 MALAYSIAN JOURNAL OF VETERINARY RESEARCH VOLUME 1 NO. 1 JULY 2010

Total rainfall (mm) vs helminth c as es and s mall ruminants population in the districts of Perak for 2008

9,000 8,260 2000 8,000

7,000 6,171 1500 6,000 5,621 5,000 3,826 1000 3,728 4,000 3,326 634 3,000 2,545 2,036 Helminth C as es 500 2,000 342 Total R ainfall (mm) 1,000 108 90 8 13 27 17 0 0 Kinta Perak Kuala Manjung Batang Hulu Hilir Larut Tengah Kangsar Padang Perak Perak Matang

Population in 2008 Helminth C ases in 2008 Total Rainfall 2008

FIGURE 5. Graph of total rainfall (mm) vs helminth cases and small ruminants population in the districts of Perak in 2008

T otal rainfall (mm) v s helminth c as es and s mall ruminants population in the districts of Perak for 1998 and 2008

9,000 4000 8,260 8,000 3500

7,000 6,171 3000 6,000 5,621 5,918 2500

5,000 4,534 2000 3,826 3,926 3,885 3,944 4,000 3,728 3,326 1500 3,000 2,935 2,629 Helminth C as es

Total R ainfall (mm) 2,545 2,036 1000 2,000 1,741 634 1,000 342 500 108 90 8 13 27 17 0 0 Kinta Perak Kuala Manjung Batang Hulu Perak Hilir Perak L arut Tengah Kangsar Padang Matang

Population in 1998 Population in 2008 Helminth C ases in 1998

Helminth C ases in 2008 Total R ainfall 1998 Total R ainfall 2008

FIGURE 6. Graph of total rainfall (mm) vs helminth cases and small ruminants population in the districts of Perak in 1998 and 2008

42 VOLUME 1 NO. 1 JULY 2010 MALAYSIAN JOURNAL OF VETERINARY RESEARCH

egg per gram faeces from the goats and higher population were observed in most sheep samples received in the Parasitology districts in 2008 compared to 1998. The and Haematology Unit, VRI. This test highest population was observed in Batang is a diagnostic tool conducted using the Padang district, followed by Manjung, McMaster (Ministry of Agriculture, Kuala Kangsar, Kinta and Perak Tengah, Fisheries and Food, 1986), fl oatation while in 1998, highest population was and faecal culture methods to detect observed in the Larut Matang district, the helminthiasis problems in small followed by Manjung, Hilir Perak, Kuala ruminants. Animals with egg counts of Kangsar and Batang Padang. The highest 500 epg and above are considered to be amount of rainfall in both 1998 and 2008 signifi cantly infested with helminthiasis was reported in Larut Matang district, where treatment is necessary. The data of followed by Batang Padang, Kinta and helminthiasis cases in each district in Perak Perak Tengah districts. in the year 1998 and 2008 were correlated While there is no direct correlation with the meteorology data from the 9 observed between the high rainfall and stations according to the district location the number of cases with regard to the of each meteorology station in the state of population of small ruminants in the district, Perak. high humidity (77.3%) and moderate temperature (26.5°C) with annual average RESULT AND DISCUSSION rainfall of 2097.2 mm (1998) and 2584.7 mm (2008) reported in Perak is favourable There was consistent rainfall throughout to the lifecycle of the strongyle and the

both years in all districts and a slight survival of the infective larvae (L3). This increase of rainfall (34-1280 mm) in 2008 causes the infection to occur in the small compared to 1998 and hence, helminthiasis ruminants after 3-4 weeks of grazing on cases were found throughout the year. the infected pasture. Helminthiasis cases in the districts of Minute alterations in the local Perak showed higher cases in the year 2008 climate patterns or the potential effects compared to 1998 for all districts except for of climate change on the epidemiology of Perak Tengah district. The district of Kinta helminth parasites and the implications for reported the highest case of helminthiasis sheep farming in the Malaysia needs to be in 2008, followed by Kuala Kangsar, studied further. These changes may have Batang Padang and Hilir Perak districts, implications for the epidemiology of sheep while in 1998, the district of Kinta still helminth parasites such as the production- showed the highest case of helminthiasis, limiting disease outbreaks caused by followed by Kuala Kangsar, Perak Tengah Haemonchus contortus. and Hilir Perak districts. Figure 2 shows It has been reported by Kao et al. small ruminant populations in Perak where (2000) that additional considerations

43 MALAYSIAN JOURNAL OF VETERINARY RESEARCH VOLUME 1 NO. 1 JULY 2010 of the effects of climate and the annual replacement of host stock show that for conditions favourable for parasite transmission, this is a robust indicator of parasite epidemiology. When climate variation and annual replacement are added to the model, it is shown to reasonably describe the qualitative behaviour of an experimental data set, indicating it to be a useful tool for further investigation of some of the underlying assumptions of sheep-nematode dynamics.

REFERENCES

1. Chaudary F.R., Khan M.F.U. and Qayyum M. (2007). Prevalence of Haemonchus contortus in naturally infected small ruminants grazing in the Potohar Area of Pakistan. Pakistan Vet. J. 27(2): 73-79. 2. Kao R.R., Leathwick D.M., Roberts M.G. and Sutherland I.A. (2000). Nematode parasites of sheep: a survey of epidemiological parameters and their application in a simple model. Parasitology 121(Pt 1):85-103. 3. Ministry of Agriculture, Fisheries and Food (1986). Manual of Veterinary Parasitological Laboratory Techniques. Her Majesty’s Stationery Offi ce, London, pp 160. 4. Morgan E.R. and Wall R. (2009). Climate change and parasitic disease : farmer mitigation? Trends in Parasitology. 25(7): 308-313. 5. Taylor M.A., Coop R.L. and Wall R.L. (2007). Veterinary Parasitology. Blackwell Publishing, 3rd ed., pp 5. 6. Waller P.J. and Chandrawathani P. (2005). Haemonchus contortus: Parasite problem No. 1 from Tropics-Polar Circle. Problems and prospects for control based on epidemiology. Tropical Biomedicine 22(2): 131-137.

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