The pork industry is learning how to best utilize and profit from feeding ractopamine hydrochloride. Producers and nutritionists report the results of their on-farm trials.

After completing a 1,200-head trial, Paul Fitzsimmons has tailored his feeding programs to maximize the benefits of Paylean, Elanco Animal Health's brand name for ractopamine hydrochloride.

"There is a different benefit for each of the sexes," he says. "There is a lean percent increase and yield increase for the barrows, but only feed efficiency increases for the gilts because they are already lean enough."

Fitzsimmons is one of the sons of Robert Fitzsimmons and Sons based in Mapleton, MN.

The farm now feeds barrow rations with 9 g./ton of Paylean for four weeks with a goal of marketing 70% of the barrows in that four-week window. The gilts are fed a step-up program of 4.5 g./ton for two weeks and 9 g./ton for four weeks to maximize their feed efficiency.

Paylean is a feed ingredient that directs nutrients to lean muscle development and away from fat production.

Here are the parameters of the trial: 600 gilts and 600 barrows were divided into control and test groups in double-curtain-sided, totally slotted, 600-head barns. The pigs were from PIC Camborough-15 sows and the PIC 280 Duroc sire line.

Paylean was fed at 18 g./ton for six weeks. Diets contained 16% crude protein, and lysine increased 25% in the first three weeks and 20% in the last three weeks.

Each group was marketed to Hormel Foods on three days in August and September 2000. Barrows averaged 273-lb. market weight and 92.7% were marketed within 36 days of feeding Paylean. Gilts averaged 278 lb. and 76.7% were marketed within 47 days of feeding Paylean.

Hot carcass weight in the Paylean-fed pigs increased 1.01% for the barrows and 1.42% for the gilts. Last rib back fat decreased 0.06 in. for the barrows and 0.02 in. for the gilts.

A total of 14.7% more barrows and 3.9% more gilts fell into Hormel's "red box," an area on the packer's grid where producers can earn more than 100% of their base contract price.

Based on those carcass merit increases, the increased net value/pig was $5.08 for barrows and $3.48 for gilts. For economic and cost analysis, see Table 1.

During the entire finishing period, both the control and Paylean-fed groups had 2.5% death loss, Fitzsimmons says. Two hogs from the control groups died in transport to the packing plant.

Mixed Results Dean Koehler, swine nutritionist at Agri Nutrition Services, Shakopee, MN, has worked with several farms that have experienced either no increase or only slight increases in death loss with Paylean use.

But, he also has documented a couple of cases in which death losses, both in the barns and during transportation, have increased significantly.

"Yet it is hard to make complete sense out of what is happening, as I know of herds with nearly identical animals that have fed Paylean with little or no problem," he says.

Genetics, housing, health status and environmental conditions each may play a role in how hogs respond to Paylean.

The producers' marketing program also plays a role in determining the appropriate Paylean feeding program, he says.

The majority of hogs within a group should be fed 9 g./ton for no more than 28 to 35 days. The first hogs marketed should be fed Paylean for at least one week.

Test on Limited Number Koehler advises clients to test Paylean on a limited number of hogs to determine how their genetics, facilities and health status will affect performance. Each farm will be different, he says.

"This product has to be examined on a case-by-case basis," he says. "The payback is different in every case. It depends if you run the barns on a tight schedule and are marketing at lighter weights than you want to. It also depends on where your hogs fall on your packer's grid."

Brian Richert, animal scientist at Purdue University, echoes Koehler's suggestion.

Non-Paylean fed hogs that yield 52-54% lean, sold to a packer that pays significant premiums for lean carcasses, will benefit the most from Paylean, he explains.

On the flip side, hogs with 54% or higher lean percentage may not return enough carcass premium to justify the expense.

"However, producers need to consider that they will put on 8 to 10 more pounds of lean in the same amount of time," he says.

Another On-Farm Trial Kevin Hugoson tested Paylean on 600 finishers in May and June 2000. Based on that test, the Granada, MN, producer reports an increased net return of $2.69/market hog.

Hugoson divided 600 head of PIC (Camborough X PIC 280) pigs by sex. The barrows and gilts were then split into 150-head control and Paylean-fed groups in a 600-head, double-curtain-sided, totally slotted facility.

Paylean was fed at 18 g./ton for 42 days in the last two phases of a six-phase finisher diet program. Both the control and Paylean diets fed to the barrows contained 16.4% crude protein and 0.93% lysine for 21 days and 15.9% crude protein and 0.79% lysine for the next 21 days.

An assay of the feed revealed a mixing error in the gilt diets, which were found to contain less than 18 g./ton of Paylean. Therefore, these results are for the barrows only.

The hogs were delivered to Hormel Foods' Austin, MN, plant on three days in June. Average market weight was 270 lb.

The control barrows had a 74.33% yield, compared with 76.03% for the Paylean pigs. Tenth rib backfat averaged 0.98 in. for the control and 0.94 in. for the Paylean group.

The control hogs netted Hugoson 104% of his base contract price, while Paylean pigs earned 104.86% of the base price. In addition, 2.3% more Paylean-fed pigs fell into Hormel's red box. The increased carcass merits total $4.96/head.

Hugoson figures feed savings of $1.79/pig for a total advantage of $6.75/pig. The feed efficiency was 0.21 lb. better for the Paylean-fed hogs, Hugoson says.

The costs include $3.46 for Paylean and $0.60 for additional crude protein and lysine - a total of $4.06/head.

Therefore, Hugoson's net value of feeding 18 g./ton of Paylean for 42 days was $2.69/head.

Based on the test pigs, Hugoson has adjusted to feed 9 g./ton of Paylean for 28 days to all finishing hogs. He estimates feeding this rate will return $2.88/pig.

Packer Response IBP spokesman Gary Mickelson says that their buying program rewards producers' efforts to raise higher-yielding, leaner animals. The packer does not endorse specific products used by producers.

Officials at Hormel Foods declined to comment on Paylean-fed hogs.

Three producers are delivering Paylean-fed hogs to Hatfield Quality Meats, Hatfield, PA, according to Duff George, manager of hog procurement for the plant.

The 7,000-head/day plant uses the AutoFOM system to grade all hogs, and producers who deliver Paylean-fed hogs receive premiums based on the carcass improvements.

Questions Remain Koehler reminds that Paylean is a complex product and that questions remain unanswered about its application to the pork industry.

"We haven't determined the best dosage. We haven't determined what the carcass response will be under industry conditions, and we have just started to address the death-loss issue," he says.

Research trials and the first six months of on-farm use of Paylean have helped the company and producers identify the proper timing and dosage of Paylean, according to Dennis Erpelding, manager of government relations and public relations for Elanco.

"We have learned that 28 days at 9 g./ton will return the best economics in the field," he says.

Richert raises two more issues facing the product. Paylean is only approved by the Food and Drug Administration to be fed up to 240 lb., much lighter than the USDA reported average market weight of 262 lb.

Additionally, feed-grade antibiotics are not allowed in Paylean-supplemented rations.

Richert points out that finishing pigs being treated with feed-grade antibiotics for ileitis cannot also be fed Paylean.