According to research conducted at the University of Guelph in Ontario, Canada, supplemental lighting increases feed and water intake and bodyweight gain of calves.
The researchers provided calves from birth to eight weeks of age with either 18 hours or 10 hours of continuous light. Calves exposed to the 18-hour regimen weighed almost 18 pounds more at eight weeks of age than the calves exposed to 10 hours of lighting. The calves on the 18-hour regimen also ate more calf starter and drank more water. The table below summarizes the results.