Incidence of Hyperthermia and its Management in Weaner Bharat Merino and Avihill Lambs in Himachal Pradesh

The critical condition of hyperthermia was recorded in Bharat Merino and Avihill lambs (3 to 4 months old) in the north temperate region of Himachal Pradesh in April 2024 (ambient temperature 30°C and relative humidity 63.5%). Four lambs exhibited symptoms of hyperthermia, lethargy, hyperextension of hind limbs, panting, rectal temperatures (41.6 to 42.0°C), along with tachycardia, tachypnoea, enhanced bronchovesicular sounds, higher haemoglobin (13.82±0.31 g%), packed cell volume (32.75±0.93%), and total erythrocyte count (14.55±0.27 x10⁶/µl). All the lambs were immediately shifted to cool places, followed by intravenous infusion of normal saline solution (20-30 ml/kg body weight). Two lambs were intramuscularly administered procaine penicillin (20000 IU/kg), pheniramine maleate (1.0 ml, Avilin) and Tribivet® (1.0 ml). The other two lambs were managed without antibiotics but received the same treatment. All the lambs responded positively, and rectal temperatures dropped to ~39.4°C within one hour of treatment. The cooling measures, fluid therapy, and supportive care were found to be effective for managing hyperthermia in Bharat Merino and Avihill lambs.