Vampire Bats on Treadmills: Unveiling Their Unique Metabolism

Recent experiments involving vampire bats running on treadmills have unveiled their intriguing method of deriving energy from proteins, a byproduct of their unique diet. Unlike most mammals, which primarily rely on fats and sugars for energy, these three species of vampire bats feast on blood, a nutrient-rich but fat- and sugar-poor sustenance. This raises questions about their metabolism, as amino acids typically contribute less than 10 percent of energy during exercise in the animal kingdom.

To delve deeper into their metabolic process, Kenneth Welch and Giulia Rossi from the University of Toronto studied 24 common vampire bats (Desmodus rotundus) captured in Belize. The bats were given cows’ blood infused with amino acids containing labelled carbon atoms before being placed in a treadmill apparatus.

The researchers measured the bats’ metabolic rates by tracking their oxygen consumption and carbon dioxide output while they ran at speeds reaching 30 metres per minute. Analysis of the carbon isotopes in the bats’ exhalations revealed they were primarily sourcing energy from their recent meal, rather than from stored fats or sugars.

While most animals convert nutrients into sugars and fats for future use, vampire bats have adopted a distinct strategy that makes them particularly vulnerable to starvation—they risk depleting their energy reserves within just 24 hours of not feeding. To counter this vulnerability, these bats forge strong social bonds, often sharing meals by regurgitating blood for their companions, ensuring the survival of the group.