A prominent industry representative once posed the question: “If 99% of the hogs marketed are successfully transported to the slaughter facility without injury, fatigue or death, should producers be concerned with 1% transport loss?”

Most businesses would be satisfied with a 99% success rate. But in these exceedingly tight financial times, even this very small fraction serves as an opportunity to deliver more full-value pigs by curtailing transport losses and unwitting mortalities.

An Iowa State University (ISU) study of over two million pigs, in collaboration with a Midwestern pork producer, reported that 0.85% of those transported to a commercial processing plant were fatigued, injured or prematurely dead (summed to equal transport losses). Ultimately, this yielded approximately 17,000 pigs with potential for reduced value.

In addition, a recent review of 22 field trials included 27,240 trailer loads of pigs transported to U.S. slaughter plants between 2000 and 2007. The review by Matt Ritter, Elanco Animal Health, recorded loss averages between 0.14 to 2.4% per trailer load.

Clearly, transport to market is the worst time to incur pig losses because the cost of feed, labor, medicine and capital investment has been accumulated.

Transport losses are described as the sum of fatigued, injured and dead pigs during transport to the processing facility or during lairage (the time of rest at the plant before slaughter).

Fatigued pigs exhibit blotchy red skin, muscle tremors and a reluctance to move. If federal legislation prohibits fatigued (or nonambulatory) pigs from entering the human food supply, as is the case in cattle, those pigs would have little if any value.

Injured pigs may incur reduced value if a portion or the entire carcass is condemned. Of course, dead pigs have no market value, often leaving producers to cover the cost of carcass disposal when death occurs during transport or lairage.

Associated Factors

Drawing on the collective studies noted, ISU researchers and a commercial pork integrator teamed up to take a closer look at the factors associated with fatigued, injured and dead pigs during transport to a processing facility.

Factors contributing to transport losses, such as pig density in trailers (pig weight/transport square feet), sort from the barn, season, temperature, management and others, were studied.

Researchers evaluated 9,651 trailer loads transporting over 2 million pigs to a single processing plant. Transport losses totaled 17,393, an average of 0.85% per trailer load. From that total, 0.55% were recorded as “fatigued” pigs, while 0.05% and 0.25% were listed as injured or dead, respectively.

Management and environmental effects, such as sorting/loading personnel, procedures, facilities, etc., can play a large role in transport losses.

Breaking the data down further, transport losses for the 29 truck drivers ranged from 0.54 to 0.78% per truckload, averaging 0.64%; the 11 loading crews' transport losses ranged from 0.35 to 0.86%, and averaged 0.65%. Of the nine farms in the study, transport losses ranged from 0.28 to 1.21%, for an average of 0.69%. Notably, two farms averaged greater than 1% total losses per trailer load (165 pigs), which calculates to 1.65 pigs per trailer load.

At 1% transport losses spread over 50 trailer loads of pigs, this would equal approximately 83 pigs with the potential for reduced value (165 pigs/trailer × 50 trailers = 8,250 pigs transported × 1% transport loss = 82.5 pigs).

While this study did not identify specific characteristics of truck drivers that may contribute to greater transport losses, a few possibilities could include the frequency and duration of stops and the gentleness of starts and stops. Temperatures inside the trailers rapidly increase when the trailer is not moving and when truck drivers do not manage the air inlets to recommended guidelines.

Similar observations can be made about loading crews. Of the 11 crews evaluated, the poorest four load-out crews in terms of greatest average transport losses averaged 0.28% more pig losses during transport when compared to the best four load-out crews. Thus, proper pig handling throughout the process of sorting, moving and loading is important.

In the ISU study, pigs were removed from the grow-finish barns in two or three sorts. Analysis of the first and third sort (approximately 2-3 weeks apart) found that pigs removed during the third sort averaged 0.27% more transport losses compared to the first sort. This result may be due to slower-growing, less healthy pigs or other factors. Regardless of the reason, pigs in the latter sort may have different floor space and/or handling requirements during the loading process.

Next Page: Focus on Pig Density