Dr. Gustavo M. Schuenemann, Professor, Department of Veterinary Preventive Medicine, The Ohio State University
Whether calves are moved to an off-site heifer grower, calf ranch, veal facility, or sale barn, the decision to ship a calf must begin with a simple but critical question: Is this calf fit for transport? Fitness for transport directly affects calf health, survival, and performance. In the U.S., under the USDA Twenty-Eight Hour Law, animals may be transported for up to 28 consecutive hours during interstate transport.
What Does “Fitness for Transport” Mean?
According to the American Association of Bovine Practitioners (AABP), fitness for transport refers to an animal’s ability to withstand transportation without compromising their welfare.
What are the Minimum Criteria for Calves Fit for Transport?
Based on a recent study assessing short- and long-distance transport, following a clear and robust fit-for-transport protocol matters for calf survival and performance. Calves should only be transported if all of the following conditions are met:
- Maternity: Clean, dry environment with strong emphasis on hygiene.
- Navel (umbilicus): Thoroughly disinfected, completely dry, and without signs of swelling.
- Adequate colostrum intake: The calf has received colostrum or an approved colostrum replacer and is at least several hours post-feeding. A second colostrum meal has been shown to reduce the probability of calf diarrhea by 50%, which is the leading cause of preweaning mortality.
- Recently fed and hydrated: The calf has been fed, has access to water, and shows no signs of dehydration (sunken eyes, skin tenting, dry mouth). A conditioning protocol consisting of at least four consecutive milk meals (two per day), supplemented with oral electrolytes and access to free-choice water, offers a clear opportunity to assess fitness for transport (additional details here). Considering the time spent in the maternity period plus the conditioning protocol, calves would be at least 3 days old, aligned with the Dairy Animal Care and Quality Assurance guidelines.
- Dry and thermally stable: The hair coat is completely dry; calves are protected from cold stress (adequate bedding, ventilation, calf jackets when needed).
- Clinically healthy: Alert, responsive, normal posture, and without signs of systemic illness (fever, depression, labored breathing, diarrhea with dehydration).
- Handling calves with care: Gentle loading and unloading, emphasizing safety for both calves and personnel.
- Free of injury: No fractures, open wounds, swollen joints, or umbilical infections causing pain.
- Ambulatory and strong: Able to stand and walk unassisted, bear weight evenly, and maintain posture.
- Properly identified and documented: Individual ID, treatment records, and required transport paperwork are complete.
These principles are consistent across AABP, FARM program, Dairy Animal Care and Quality Assurance, and US federal transport guidance.
Which Calves are NOT Fit for Transport?
The following calves must not be transported (except directly for veterinary care):
- Non-ambulatory calves: Unable to stand or walk without assistance.
- Dehydrated calves: Sunken eyes, prolonged skin tent, weakness.
- Unable to thermoregulate.
- Recent surgical procedure (e.g., hernia).
- Sick calves with:
- Severe or watery diarrhea
- Fever or marked depression
- Pneumonia or rapid breathing
- Injured calves:
- Fractures or injury
- Open wounds or severe lameness
- Painful navel swelling/infections or swollen joints
- Neurologic signs:
- Head tilt, ataxia, seizures, inability to rise
- Newborn or unstable calves:
- Wet calves, calves not yet recovered from birth, or calves that have not yet fed.
AABP guidelines are explicit: Non-ambulatory calves are not fit for transport and should not leave the farm of origin unless transported for veterinary care.
What are the Best Practices Before and During Transport?
- Properly train personnel to assess calf fitness consistently.
- Delay transport when calves are borderline: Rest, rehydrate, feed, and reassess.
- Use clean, dry, well-bedded trailers to reduce slipping and disease transmission. Trailers should be sanitized after each use.
- Adjust for weather: Ventilation in heat, appropriate bedding and calf jackets in cold.
- Avoid overcrowding and commingling calves of different sizes.
- Provide adequate space per calf (AABP fit for transport guidelines and calf transport study).
- Have a clear euthanasia protocol for compromised calves, developed with the herd veterinarian.
Where are the Greatest Opportunities to Improve Calf Survival and Growth?
While fitness for transport matters, calf immunity, resilience, and lifetime performance are largely determined before and around birth. Current evidence shows that health-related factors early in life have a much greater impact on calf mortality at weaning than transport duration. The greatest opportunities to improve calf outcomes lie in four interconnected stages:
1) Prepartum: The Last 60 Days of Gestation
Approximately 50% of fetal growth occurs during this period, alongside rapid development of the calf’s immune system, gut barrier, lungs, and neuroendocrine regulation. The last 60 days of gestation are a critical window for fetal programming. Key systems developing during late gestation include:
- Lymphoid organs (e.g., thymus, spleen, lymph nodes).
- Innate immune cells (e.g., neutrophils, macrophages).
- Gastrointestinal and respiratory epithelial barriers.
- Hypothalamic pathways regulating stress, thermoregulation, and gut permeability.
Prepartum nutrition and inflammation status directly shape calf immunity at birth. Inadequate energy balance, protein supply, trace minerals (Zn, Se, Cu), vitamins (A, E) or excessive maternal inflammation (e.g., heat stress, TMR contaminated with mycotoxins) can impair immune development, even when colostrum absorption appears adequate.
2) Maternity: Hygiene and Colostrum Management
Calves are born agammaglobulinemic (no circulating IgG, IgM, or IgA), but they are not immunologically naïve. Their ability to respond to pathogens depends on both fetal programming and passive transfer of immunity. Key maternity priorities include:
- Gentle handling of dams and newborns.
- Clean, dry calving environments to minimize pathogen exposure.
- Timely delivery of quality colostrum (1 gallon with ≥23% Brix within 2 hours of birth, followed by a second 0.6-gallon meal 6 hours later) with minimal bacterial contamination.
- Proper personnel training and monitoring (e.g., Brix, serum IgG, surface ATP swabs).
Colostrum intake is necessary but not sufficient. Calves with compromised fetal development may absorb IgG normally yet still show poor immune responsiveness. Maternity management bridges fetal programming and postnatal immunity.
3) Transport: Comfort and Logistics
Fitness for transport is a management decision at the farm of origin in which transport outcomes reflect decisions made before the truck arrives at the calf-raising facilities. Critical transport factors include:
- Fitness-for-transport assessment (hydration, thermoregulation, mobility).
- Thermal comfort to protect from cold or heat stress.
- Adequate bedding, ventilation, and space per calf.
- Gentle handling during loading and unloading.
- Clear logistics to minimize delays and unnecessary handling.
- Proper training of both truck drivers and farm personnel.
4) Preweaning: Feeding, Housing, and Daily Management
Preweaning performance is where early-life advantages or disadvantages become visible in terms of morbidity, mortality, and growth rate through weaning. Key high impact preweaning factors include:
- Access to clean free-choice water and adequate nutrition (fluid and solid diet) to support growth and immune function.
- Consistent feeding schedules and milk hygiene.
- Clean, dry, well-ventilated housing with appropriate bedding.
- Thermal comfort and protection from environmental stress.
- Early disease detection, timely intervention, and pain management.
- Proper personnel training following standardized protocols.
The evidence shows that early-life and management factors play a much larger role in calf mortality at weaning than transport duration when following well-established fit-for-transport practices. An ounce of prevention is worth a pound of cure. Please have this discussion with your veterinarian and nutritionist. Attention to these details make the difference in terms of calf survival and performance at the end of the day.