Allan P. Schinckel Purdue University

Publish Date: March 25, 2010

Pork producers have the goal to efficiently produce lean, quality pork to meet consumer demands for lean high quality meat products. The implementation of lean value carcass pricing systems has led to the selection of pigs with increased lean growth rates, increased carcass lean percentages and improved lean feed conversion. Health, nutrition, and facility management strategies have been implemented across the swine industry to increase commercially achievable lean growth rates. Paylean (Elanco Animal Health) is a feed additive that when added to a swine diet increases the rate and efficiency of muscle tissue growth and reduce fat deposition. The active ingredient in Paylean is ractopamine hydrochloride. Paylean was approved in 1999 to be fed at levels of 4.5 to 18 grams per ton (5 to 20 ppm) from 150 to 240 lbs live weight (last 90 lbs of live weight gain prior to slaughter). However, in 2006 the FDA approval was modified to reduce the maximum dietary level fed (4.5-9.0 g/ton) and removal of the upper weight restriction such that Paylean can be fed for the last 45-90 lbs of weight gain prior to slaughter. Because of the increased muscle growth and protein accretion, pigs fed Paylean have increased dietary essential amino acid requirements and have a minimum dietary crude protein requirement of at least 16% CP based on label restrictions.

Publish Date: September 18, 2006

Purdue University 1995 Swine Research Report. Betaine, a byproduct of molasses production from the sugar beet, has recently received a great deal of attention as a livestock feed additive. Little is currently known about the exact action of betaine on body metabolism, however, betaine is an intermediate in the metabolism of choline and has shown possibility as a replacement for choline and methionine in poultry diets. Betaine has also been suggested and promoted for swine to reduce carcass backfat, increase lean composition, as well as improve feed efficiency. Subsequently, it was suggested that the betaine feeding should be initiated at lighter weight and fed for longer intervals. Thus, the objective of this experiment was to evaluate the effectiveness of betaine in altering pig performance and composition from 60 to 110 kg live weight. A recent study by Schinckel and Cera investigated responses to betaine in barrows and gilts of two different lean genetic potentials, when fed from either 83 kg or 104 kg to about 116 kg body weight. Results showed no influence of feeding betaine on either fat depth, loin eye area or lean percentage for pigs in either genotype and either sex. An impersoned feed-per-gain ratio resulted for gilts, but not barrows,when betaine was fed beginning at either 83 kg or 104 kg.

Publish Date: September 18, 2006

Purdue University 1996 Swine Research Report. Consumers and carcass-value marketing systems continue to demand the efficient production of lean pork from today's swine producers. Halothane reactor pigs (nn) are known to have a higher percent of carcass lean when compared to non-carriers (NN) of the halothane gene, making the halothane gene a source of interest to the commercial swine industry. However, nn pigs are also more susceptible to stress and have poorer muscle quality. The muscle quality and carcass characteristics of halothane-carrier (Nn) pigs has not been well defined. This study examined the effects of the halothane gene on muscle quality and carcass composition traits.

Publish Date: September 18, 2006

Purdue University 1996 Swine Research Report. To remain competitive, pork producers must efficiently produce the quality lean pork that consumers demand. Lean growth rate, lean efficiency (the pounds of feed per pound of lean), and total production dollar cost per pound of lean are the important traits for the future. Lean growth trials conducted in the late 1980's at Purdue University and the University of Kentucky, indicated that large amounts of variation exist between different genetic populations or genotypes of pigs. In the early 1990's, new seedstock were imported from Canada and Europe resulting in additional genetic choices.

Publish Date: September 18, 2006

Purdue University 1996 Swine Research Report. Accurate genetic evaluation must account for as much environmental-management variation as possible. Past studies have indicated that first parity litter size can increase as age at farrowing is increased. Other studies indicate that if first parity gilts are allowed to skip one estrous cycle, second parity litter size can be increased. Additional data also has indicated that weaning pigs less than 17 days of age can affect litter size of the following litter. Based on these results, farrowing records were analyzed to evaluate the effects at age of first farrowing, weaning age, and days from weaning to successful breeding on sow farrowing performance.