It's just that keeping your heart rate in the target range during regular aerobic exercise has been shown to be safe and effective for increasing your aerobic fitness. Exercising above this range can be very uncomfortable and may increase your risk of injury.
Typical daily weight gains for feedlot animals ranges between 0.5kg to 2.5kg per day, while grass fed animals are somewhat lower than this. The following data was collected from a small beef cattle company in Dallarnil in Queensland (approximately 300km north of Brisbane).
Expressed as a percentage of live weight, milk consumption tends to go down as dairy heifer calves with free-choice milk, water and calf starter grain get past about three to four weeks of age. In the figure above note the 9.5 qts.daily for the average Holstein calf daily milk intake at 5 days.or the Holstein calves in the figure above (about 160 lbs.) as they approached 35 days their milk intake (as a percent of live weight) dropped down to about 14 percent.