Prevalence of Haemonchus contortus in Naturally Infected Small Ruminants Grazing in Potohar Area, Pakistan
F.R.CHAUDHRY*, M.F.U.KHAN AND M.QAYYUM
ABSTRACT The
prevalence of gastrointestinal nematodes (GIN) in tropical and sub-tropical areas has adversely affected the production potential of sheep and goats, leading to countless deaths and insidious economic losses in livestock sector. Among GIN, Haemonchus contortus considered main culprit causing anaemia and hypoproteinaemia in small ruminants.
The present study was carried out to investigate the prevalence and seasonal trend of the Haemonchus contortus in sheep and goats in the Potohar areas of northern Punjab, Pakistan from December 2004 to January 2006. Faecal samples collected from 968 sheep and 961 goats of different breeds were examined by the modified McMaster technique using saturated solution of sodium chloride. Results revealed that the
infection was significantly (P<0.05) higher in sheep compared to goats. The peak infection level was recorded during rainy season (July-October). On the other hand, low infection level was noted from December up to May. In sheep, highest log faecal egg counts (LFECs) were recorded in Islamabad, followed by Attock, Jhelum and Chakwal. However, in goats the LFECs trend was highest in Islamabad, followed by Jhelum, Attock and Chakwal districts. A significant (P<0.05) variability in LFECs was noted between sheep and goat breeds from site-site, while no significant difference was observed between breeds at the same site. Hairy (Jattal) goats and Salt-Range (Latti) sheep breeds exhibited significantly reduced LFECs level along with higher packed cell volume (PCV) and hemoglobin (Hb) levels compared to other breeds. Moreover, FAMACHA© chart scoring in relation with worm infection (FECs) was more valid in sheep than goats. High prevalence of H. contortus in Potohar area was due to favorable agro-climatic conditions that favor the development and survival of the free-living stages of H. contortus . The above findings are discussed with regard to their relevance for strategic control of haemonchosis in small ruminants.
Key words: Gastrointestinal nematodes, Haemonchus contortus, prevalence, agro-climatic conditions, sheep, goats, Potohar area, Pakistan