Morphological identification of Gastrointestinal Nematode L3 Larvae in small ruminants

Gastrointestinal (GI) nematode infections remain one of the major constraints in small ruminant production, particularly in tropical regions. This study aimed to identify the third-stage (L3) larvae of strongyle nematodes recovered from sheep and goats in selected districts of Tamil Nadu using coproculture and morphological keys. A total of 24 farms across Pudukkottai, Sivagangai and Tiruchirapalli districts were included, and pooled faecal samples from each farm were subjected to coproculture. The infective larvae were identified based on established morphological characteristics. The predominant genera detected was Haemonchus. In addition to Haemonchus, larvae of Trichostrongylus, Oesophagostomum and Bunostomum were also detected, indicating that mixed strongyle infections are common under extensive and semi-intensive farming systems. The study highlights the distribution of GI nematode larvae in small ruminants and emphasizes the role of coproculture-based morphological identification in epidemiological investigations under field conditions.