Shipping, no fever
Shipping recently weaned calves from their home ranch to a stocker operation or feedyard, with associated stress and pathogen exposure, can contribute to sickness. Careful management can minimize shipping stress and morbidity though, as demonstrated in some of the longest hauls of all – from Hawaii to the U.S. mainland.
During the recent Academy of Veterinary Consultants conference in Denver, Ashley Stokes, DVM, PhD, Assistant VP for Engagement and Deputy Director for Extension at Colorado State University, outlined how Hawaiian producers prepare and transport their calves to mainland feedyards while minimizing negative effects of the weaning and shipping process. Previously, Stokes served as Extension Veterinarian at the University of Hawaii and worked closely with cow-calf producers in designing systems for preparing and transporting their calves.
Stokes points out that cattle ranching has a long history in Hawaii, with about 800 ranches including three of the top 25 ranches in the United States. While the market for local, grass-finished beef has grown in Hawaii, slaughter capacity is limited and most calves ship to the mainland for growing and finishing. Feedyards have operated in Hawaii in the past, but most of the feed was imported and it turns out to be more cost-effective to ship calves to the mainland than to import the feed.
Hawaiian producers have shipped cattle on modified cargo airplanes, but the costs are high. Specialized livestock ships – like floating stockyards – work well, but none are registered in the United States and regulations prevent foreign-registry vessels from transporting goods between U.S. ports. So, the Hawaiian cattle industry developed a system using purpose-designed shipping containers nicknamed “cowtainers,” which provide ample space, ventilation, bedding, ease of cleaning and overall comfort for calves through nine days of transport by ship. Trained stock tenders travel with the cattle, ensuring good care and plenty of feed and water.
Hawaiian producers, working with the university and their state association, developed weaning and preconditioning protocols to prepare their calves, involving comprehensive vaccine protocols, a 30-day hold after weaning and, importantly, plenty of exposure to feed bunks and water troughs.
Stokes and researchers in Hawaii, in cooperation with Iowa State University, conducted a study to evaluate long-haul shipping stress for cattle transported from Hawaii to the mainland United States. The researchers monitored two shipments of calves, one to California and one to Washington, using bi-level, four-compartment cowtainers. They installed instruments in each compartment to monitor temperature and humidity throughout the journey, and also fitted three heifers in each compartment with vaginal thermometers to monitor body temperature.
They also collected blood samples from all of the calves prior to shipment, upon arrival and six days post-arrival for analysis of physiological stress indicators.
The researchers found that body temperatures tended to rise above normal during stressful events, such as loading and unloading from cowtainers, but soon returned to normal. Blood analysis indicated minor, short-term increases in stress levels during shipping. Shrink from pre-shipment to arrival was 6.4 percent, but the calves compensated with 9.9 percent gain on pasture over the six days following arrival. The researchers concluded that beef calves shipped from Hawaii to the mainland United States using the preconditioning and shipping protocols for this study demonstrated few and transient physiological indicators of stress.
For more, read “Looooong-Haul Cattle” from BovineVetOnline.com.
