title: Effects of feeding frequency on meat quality traits and Longissimus muscle proteome in finishing pigs.
abstract: Sixty-four barrows with an initial body weight of 59.8 ± 2.1 kg were allocated to one of the two feeding frequency regimes (had free access to diet and fed two meals per day). Pigs had free access (FA) to feed were fed on an ad libitum basis during the 8-week experimental period. Pigs fed twice daily (M2) were allowed to consume their meals in 2 h. Pigs fed twice daily had lower average daily feed intake (p < 0.01) and average daily gain (p < 0.1), but a greater G:F (p < 0.05) than FA pigs. Lower perirenal fat deposition, hot carcass weight, intramuscular fat content (p < 0.05) and dressing percentage (p < 0.1) were found in M2 pigs compared with FA pigs. Activities of citrate synthase, β-hydroxylacyl-CoA dehydrogenase and lactate dehydrogenase were greater in the Longissimus muscle (LM) of M2 pigs compared with FA pigs (p < 0.05). Proteomic analysis revealed that expression abundances of proteins involved in glucose metabolism, energy production and lipid utilization were upregulated, but expression levels of proteins participating in protein and amino acid metabolism, stress response and redox homeostasis were downregulated in the LM of M2 pigs than those in FA pigs (p < 0.05). In conclusion, the less meal frequency impairs growth rate, has marginal effects on carcass and meat quality traits and affects expression abundances of proteins in the LM of finishing pigs.
authors.affiliation: School of Life Science and Engineering, Southwest University of Science and Technology, Mianyang, China.|State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China.
authors.forename: J B
authors.initials: JB
authors.lastname: Liu
authors.affiliation: School of Life Science and Engineering, Southwest University of Science and Technology, Mianyang, China.
authors.forename: X
authors.initials: X
authors.lastname: Cai
authors.affiliation: School of Life Science and Engineering, Southwest University of Science and Technology, Mianyang, China.
authors.forename: H
authors.initials: H
authors.lastname: Xiong
authors.affiliation: State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, China.
authors.forename: H F
authors.initials: HF
authors.lastname: Zhang
mesh_terms: D000821:Animal Feed; D000822:Animal Husbandry / Q000379:methods*; D000818:Animals; D001823:Body Composition; D008297:Male; D008460:Meat / Q000592:standards*; D018482:Muscle, Skeletal / Q000378:metabolism*; D020543:Proteome; D013552:Swine / Q000502:physiology; D013997:Time Factors
chemical_list: D020543:Proteome
keywords: feeding frequency; meal frequency; meat quality; pigs; proteome