How Calf Age Impacts Health During Transport

By Blake Jackson

Moving young calves can place significant strain on their developing systems. During transport, calves may go without milk or water for extended periods, encounter unfamiliar animals, and face fluctuating temperatures.

These combined stressors can slow growth, weaken immunity, and increase disease risk. Thoughtful preparation before shipping is essential to protect calf health and long-term performance.

Calf Age at Transport

Research highlighted by Jessica Mitchell, Ph.D., of Penn State Extension shows that most U.S. calves are transported before one week of age, with some moved within 24 hours of birth. Because immunity is still developing, very young calves are highly vulnerable. Studies indicate that delaying transport improves outcomes.

Calves shipped after 10 days of age show fewer respiratory problems, while those transported at 13-24 days are less likely to arrive dehydrated or scouring.

Moving calves at 28 days has even been associated with cutting mortality rates in half compared to transport at 14 days. Older calves are generally stronger and better equipped to handle stress.

Nutrition Before Shipping

Federal regulations allow calves to be transported for up to 28 consecutive hours, making pre-transport nutrition critical. Research shows calves fed milk replacer before a six-hour trip maintained better energy levels than those fed electrolytes alone.

Providing a milk meal just before departure or during a rest stop-helps support glucose levels, reduce weight loss, and promote healthier recovery upon arrival.

Assessing Fitness for Travel

Many calves reach raising facilities already dehydrated, scouring, or fighting infections. Calves with untreated navel infections or those appearing dull and depressed are at greater risk of illness and death. Only calves that received adequate colostrum and appear bright, alert, and healthy should be transported. Body weight also matters; heavier calves consistently experience lower rates of disease and mortality.

Shorter trips reduce stress. Calves hauled for six hours experience fewer metabolic challenges than those transported 12 to 16 hours. Extended periods without feed force calves to rely on limited body fat reserves, weakening immune defenses.

Best Management Practices Recommendations:

• Schedule calf transport at 3-4 weeks of age when possible, allowing time for immune development and stronger body weight before exposure to transport stress.
• Provide a full milk feeding immediately before loading and plan milk feedings at rest stops during longer trips to maintain energy balance.
• Evaluate each calf individually prior to shipment, ensuring adequate colostrum intake and confirming the calf is bright, hydrated, and free of illness.
• Aim to ship heavier, well-grown calves, as higher body weight at arrival is linked to lower disease rates and improved survival.
• Keep hauling time as short as possible by coordinating logistics carefully and avoiding unnecessary delays to reduce metabolic stress and immune suppression.

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