title: Use of dietary supplementation with β-guanidinopropionic acid to alter the muscle phosphagen system, postmortem metabolism, and pork quality.
abstract: Rate and extent of postmortem metabolism control pork quality development. Our objective was to evaluate the role of the phosphagen system (phosphocreatine, PCr; and creatine, Cr) on metabolism and pork quality. Muscle PCr and Cr were manipulated by feeding pigs the creatine analogue, β-guanidinopropionic acid (β-GPA). In experiment 1, pigs received standard (control) diet or β-GPA supplemented (2%) diet (1 wk or 2 wk). Supplementation with β-GPA (2 wk) decreased total Cr (PCr+Cr; P=0.02) and improved pork color (decreased reflectance, P=0.003); however, β-GPA supplementation reduced growth performance (P=0.007). To separate effects of phosphagen system and growth, a second experiment was conducted with control, pair-fed, and 2 wk β-GPA (1%) supplementation; pigs were also offered a control or β-GPA supplemented flavored beverage. Neither treatment influenced pork quality. Immediately postmortem, ATP/ADP was higher in control compared to pair-fed (P<0.05); subsequently, ATP/ADP was similar among all groups. Loss of the phosphagen system may lead to adaptive changes that promote conservation of cellular ATP.
authors.affiliation: Department of Animal and Poultry Sciences, Litton-Reaves Hall, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA.
authors.forename: T L
authors.initials: TL
authors.lastname: Scheffler
authors.forename: A L
authors.initials: AL
authors.lastname: Rosser
authors.forename: S C
authors.initials: SC
authors.lastname: Kasten
authors.forename: J M
authors.initials: JM
authors.lastname: Scheffler
authors.forename: D E
authors.initials: DE
authors.lastname: Gerrard
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism; D000821:Animal Feed; D000818:Animals; D003401:Creatine / Q000008:administration & dosage; D019587:Dietary Supplements; D005260:Female; D063427:Food Quality; D006146:Guanidines / Q000008:administration & dosage*; D006863:Hydrogen-Ion Concentration; D008297:Male; D008460:Meat / Q000032:analysis*; D018482:Muscle, Skeletal / Q000378:metabolism*; D011180:Postmortem Changes; D011422:Propionates / Q000008:administration & dosage*; D013552:Swine
chemical_list: D006146:Guanidines; D011422:Propionates; D000255:Adenosine Triphosphate; D003401:Creatine; C005775:guanidinopropionic acid