The concept of shrink is a bit of an economic quirk in the cattle business. The causes of weight loss in calves are well known, particularly during the marketing phase involving weaning, gathering, sorting and transporting. The process also can involve changes in ration and extended periods in holding pens.

The economic consequences of shrink can depend on when it occurs and whether you are the buyer or seller. Shrink that occurs after pay weights are determined is bad for the buyer. Shrink prior to weigh-up is bad for the seller, but buyers, such as stocker operators, might see it as a bonus.

Oklahoma StateUniversity animal scientist David Lalman says that, traditionally, many buyers didn’t mind or complain if a rancher’s poor facilities, lack of planning or stressful animal-handling practices caused calves to lose weight prior to weigh-up. Lighter pay weights and compensatory gains make for a good deal, at least in the short term.

Longer-term consequences, though, might make buyers reconsider their opinions of shrink and work with their suppliers to minimize stress, nutritional deficiencies and sickness both before and after the sale.

Increasingly, Lalman says, research shows that the same issues that cause weight loss — stress due to poor handling, heat, overcrowding, poor nutrition or extended periods without feed or water — can reduce a calf’s immunity just at the time when exposure to pathogens is greatest. And the effects of morbidity can extend well past the receiving period, reducing cattle performance and carcass quality.

At the Beef Improvement Federation’s annual conference in June, VetLife technical services specialist Pete Anderson, PhD, outlined non-genetic factors that affect quality grade in finished cattle, based on data collected through VetLife’s Benchmark Performance Program.

Benchmark data consistently show that groups of cattle with high morbidity and mortality rates invariably grade poorly relative to the rest of the population. Anderson also says that marbling deposition is a lifetime event, not just the late stage of the feedyard phase. “Any nutritional insult, at any time in the life of the animal, will reduce marbling.”

Lalman adds that although most calves will regain weight quickly after arrival, some take longer to recover.

A short period without food or water results in fill shrink, he says, which is just a loss of rumen content, and cattle quickly gain the weight back. Tissue shrink occurs with longer periods of fasting or stress.

Lalman says recovery time can vary widely with a number of factors involved. Cattle subjected to continued stress such as sickness, commingling or a new ration could take several days or even weeks to regain their pre-market weight. He cites a study in which researchers monitored individual weights of calves shipped five hours, from fescue pasture to a feedlot. Weight loss during shipment was consistent, ranging from 39 to 50 pounds. As a group, the calves gained that weight back after seven days, but gains were variable and the range of weights widened over the first 14 days in the feedlot. After one week, one calf was still 48 pounds lighter than prior to shipment while another was 56 pounds heavier.

Lalman lists several ways in which to reduce shrink through the marketing process.

  • Minimize stress during gathering and sorting. Some shrink is inevitable during this period, he says, but cow-calf producers can protect pay weight by acclimating calves to horses, facilities and handling prior to gathering them for shipping. Spreading range cubes in or around the holding pen can attract them to the area several days ahead of time.
  • Gather a little later. A KansasStateUniversity study demonstrated that allowing cattle to graze until mid-morning resulted in heavier weights and reduced the rate of shrink during the first few hours after they were gathered.
  • Prepare calves for marketing. Calves that enter the marketing period with the best health and immunity will experience less shrink during shipping and are more likely to remain healthy, Lalman says. Ideally, preparation involves good nutrition including appropriate supplements, vaccination, weaning and low-stress handling.
  • Minimize market time. Lalman says problems often occur when buyers spend several days trying to purchase enough calves to fill a load, with some animals spending excessive time in a high-stress environment prior to transport.
  • Minimize shipping stress. Overcrowded trailers, Lalman says, are among the primary, yet preventable, causes of excessive shrink during transport. Some shrink is inevitable during shipping, but stocker operators can manage it by working with responsible truckers and loading trailers properly.