Haemato-biochemical Alterations in Sheep Due to Experimentally Induced Haemonchus contortus Infection

Sheep and goat farming is a major source of income in developed and developing countries. According to the Food and Agriculture Organisation (FAO, 2013) overall sheep population for the year 2012 was 1.2 billion worldwide, dominated by Asia (44.9%), then Africa (27.6%) and followed by America (7.3%). Majority of farm animals are infected with several species of gastrointestinal (GI) nematodes that evolved Among all the gastrointestinal nematodes belonging to family Trichostrongylidae, Haemonchus contortus is the most prevalent and highly pathogenic nematode causing severe loss to small ruminant production system. Parasite causes alterations in various physiological parameters with disturbances in haemato-biochemical blood profile. Experiment was conducted in eighteen (n=18) non-descript sheep that were randomly divided into two groups, infected (Group-A) and (Group-B) the negative control. GroupA animals were infected with 10,000 L3 of H.contortus. Larvae for the infective dose were obtained through coproculture of faeces of previously infected sheep. Animals were stall fed and were maintained separately in the animal shed to prevent infection. Haematological (Hb, PCV, TLC, DLC) and biochemical parameters (Total protein, albumin, globulin) were monitored at weekly intervals in both the groups. Results of the present study concluded that infection with H.contortus led to disturbance in haemopoietic system that led to alterations in blood haemo-biochemical profile. Mean Hb level in case of infected group (Group-A) declined from 10.83±0.59 to 4.97±0.83 at 5th week post infection (PI). Similarly, PCV dropped from 24.08±0.59 to 14.52±1.90. Mean Hb and PCV values for negative control (Group-B) remained within normal range i.e. 11.07 ±0.21 and 30.99±0.83. Leucocyte count started declining from third week PI in Group-A. By 28 days PI neutrophila and eosinophilia was observed in Group-A. Decline in albumin levels was more pronounced in infected group and reached up to 2.54±0.13g/dl at 3rd week post infection. No changes were observed in serum albumin levels throughout experiment in negative control group. Albumin to globulin ratio decreased significantly in group A on 3 rd , 4 th and 5 th week post infection as compared to negative control group. K e y w o r d s