Gastrointestinal nematode larvae in the grazing land of cattle in Guwahati, Assam

AIM To know the prevalence of gastrointestinal nematode larvae (L3) in the grazing land of cattle in Guwahati, Kamrup district, Assam. MATERIALS AND METHODS Pastures were collected and examined for the presence of nematode larvae (L3) from six localities of Guwahati at monthly interval from August 2012 to July 2013. The counted larvae were then expressed as per kg dry matter of herbage (L3/kg DM). RESULTS Examination of pastures revealed presence of nematode larvae (L3) in pastures throughout the year which varied from 4.5 L3/kg DM in January to a maximum of 106.33 L3/kg DM in August. The L3 of Haemonchus contortus, Trichostrongylus spp., Oesophagostomum spp., Cooperia spp., and Mecistocirrus spp. were recovered from pastures. The average pasture larval burden (PLB) was 34.75±3.48 L3/kg DM. Season-wise PLB revealed the presence of 23.89±3.01, 67.54±5.41, 26.67±1.92, and 7.28±0.89 L3/kg DM during pre-monsoon, monsoon, post-monsoon, and winter seasons, respectively. Monsoon season has significant (p<0.05) effect on PLB. However, analysis of variance of different locations with respect to season revealed that there was no significant difference but season-wise it was highly significant (p<0.01). Pearson correlation of environmental variables (temperature, relative humidity, and rainfall) with PLB revealed correlation was statistically significant with rainfall (p<0.05). CONCLUSION This study reveals the presence of five nematode larvae (L3) in the pastures of Guwahati, Assam throughout the year, statistically significant during monsoon season.