Influences of dietary protein sources and crude protein levels on intracellular free amino acid profile in the longissimus dorsi muscle of finishing gilts

Abstract

BackgroundThe current study was carried out to determine effects of dietary protein source and crude protein (CP) level on carcass characteristics, meat quality, and muscle amino acid (AA) profile in finishing gilts. The experiment was designed as a 2 × 2 factorial arrangement with two sources of dietary proteins (cottonseed meal, CSM vs. soybean meal, SBM) and two levels of CP (12 % vs. 14 %, as-fed basis). Seventy-two crossbred gilts (89.5 ± 0.9 kg) were allotted to one of four dietary treatments in a randomized complete block design for a period of 28 d. All diets were formulated to be isoenergetic and similar concentrations of standardized ileal digestible essential AA covering the nutrient requirements of pigs.ResultsGrowth, carcass characteristics and meat quality were not affected by dietary protein source nor crude protein level (P > 0.10) except that average daily feed intake was increased by CSM diets (P = 0.03). Gilts offered reduced protein diets had lower muscle pH45min (P < 0.05). Neither dietary protein source nor crude protein level influenced N deposition. However, reduced protein diets decreased N intake, N excretion, and serum urea nitrogen content, whilst improved N efficiency (P < 0.01). CSM diets increased N intake (P = 0.04), but did not depress N efficiency. The concentrations of phenylalanine, tryptophan, cysteine and tyrosine (P < 0.05) of the longissimus muscle were decreased when gilts offered CSM diets, while muscle intracellular free valine concentration was increased (P = 0.03). The gilts offered reduced protein diets had greater intracellular concentrations of free methionine, lysine, and total AA in muscle (P < 0.05).ConclusionThese results suggest that CSM could replace SBM as a primary protein source in finishing pig diets in terms of performance, N efficiency, carcass characteristics, and meat quality, but decrease the concentrations of muscle specific AA. Furthermore, the reduced protein diet played an important role in increasing muscle intracellular concentrations of specific free amino acids (FAA), and in reducing the relative ratios of specific FAA to lysine in longissimus dorsi muscle of pig, whose biological meaning needs further studies.Electronic supplementary materialThe online version of this article (doi:10.1186/s40104-015-0052-x) contains supplementary material, which is available to authorized users.

Evaluation of reduced amino acids diets added with protected protease on productive performance in 25-100 kg barrows

“…Consistent with results of our study, Zamora et al (2011) and Qin et al (2015) confirmed that decreasing CP by less than two percentage units in diets for fattening pigs did not affect carcass characteristics. This may be a result of better balance of AA for protein synthesis and, therefore, AA are not required as an energy source, reflected by similar LMP values with different CP concentrations (Orlando et al 2007).…”

“…In contrast, Qin et al (2015), Jiao et al (2016) and Peng et al (2016) reported that these growth variables were unaffected when CP content was reduced, but the requirement for the more limiting AA (Lys, Met, Trp, Thr) must be reached in the diet. The use of lower levels of AA in our experiment with a performance similar to that of the control protein diet, leads us to determine that a,b,c,d Means with different superscript differ (P≤0.05).…”

Integrated Remodeling of Gut–Liver Metabolism Induced by Moderate Protein Restriction Contributes to Improvement of Insulin Sensitivity

“…In Experiment 2, a total of 36, 140 days old gilts with 89.5 ± 0.9 kg BW were subjected to moderate PR by feeding the control diet (14% CP) and a protein‐restricted diet (12% CP) for 28 days. The feed intake (kg d –1 ) and final BW were not altered between two groups as previously described . At the end of the trial, pigs with the average final BW from each replicate were selected ( n = 6 for each group) and transported to a local abattoir.…”

A proteomic adaptation of small intestinal mucosa in response to dietary protein limitation

“…Protein limitation not only contributes to human health in terms of longevity extension and insulin sensitivity enhancing326 but also reduces excessive nitrogen excretion in farm animal production5. However, previous studies demonstrated that PL impeded individual growth even though all essential amino acid (EAA) were balanced to fulfil requirements of pigs1427, which may be due to NEAA deficiency28.…”

“…Dietary protein limitation (PL) has been shown to exert multiple roles in extending lifespan1, improving chronic kidney disease recovery2 and enhancing stress resistance134, as well as minimizing environmental pollution arisen from livestock farming by reducing nitrogen excretion5. Nevertheless, whether protein limitation would exert elevated or even negative impacts on intestinal physiological reaction, immune response and protein metabolism is largely unknown.…”