Lethality associated with snake venom exposure can be predicted by temperature drop in Swiss mice

Establishing humane endpoints to minimize animal suffering in studies on snake venom toxicity and antivenom potency tests is crucial. Our findings reveal that Swiss mice exhibit early temperature drop following exposure to different snake venoms and combinations of venoms and antivenoms, predicting later mortality. Evaluating temperature we can identify within 3 h post-inoculation, the animals that will not survive in a period of 48 h. Implementing temperature as a criterion would significantly reduce animal suffering in these studies without compromising the outcomes. [Display omitted] •Establishing humane endpoints to reduce mice suffering during snake venom and antivenom studies.•Implementing the 3Rs principles (replacement, reduction, and refinement) in the assessment of antivenom potency test.•Early temperature drop predicts later death in mice exposed to snake venoms or venom-antivenom mixtures.•Evaluating temperature drop, it is possible to identify as early as 1 h after snake venom exposure, mice that will succumb later.•Euthanizing animals at 3 h, based on temperature drop, in LD50 and ED50 evaluations, does not affect test outcomes.