Effects of dietary energy and crude protein levels on growth performance, blood profiles, and carcass traits in growing-finishing pigs

Abstract

This experiment was conducted to evaluate the effect of dietary energy and crude protein (CP) levels on growth performance, blood profiles, and carcass traits in growing-finishing pigs. A total of 180 crossbred pigs ([Yorkshire × Landrace] × Duroc) with an average body weight of 30.96 ± 3.068 kg were used for a 12-week feeding trial. Experimental pigs were allotted to a 2 × 3 factorial arrangement using a randomized complete block (RCB) design. The first factor was two levels of dietary metabolizable energy (ME) density (13.40 MJ/kg or 13.82 MJ/kg), and the second factor was three dietary CP levels based on subdivision of growing-finishing phases (high: 18%/16.3%/16.3%/13.2% middle: 17%/15.3%/15.3%/12.2% and low: 16%/14.3%/14.3%/11.2%). Average daily gain (ADG) and gain-feed ratio (G:F ratio) decreased as dietary CP level was decreased linearly (linear, p < 0.05; p < 0.05, respectively) in the early growing period, and G:F ration also decreased as dietary CP level was decreased linearly (linearly, p < 0.05) over the whole growing phase. Over the entire experimental period, G:F ratio decreased as dietary ME level decreased ( p = 0.01). Blood urea nitrogen (BUN) concentration was increased as dietary energy level decreased in growing period ( p < 0.01). During finishing period, total protein concentration was decreased by lower dietary energy level ( p < 0.05). In this study, there were no significant differences in proximate factors, physiochemical properties, muscle TBARS assay results, pH changes, or color of pork by dietary treatments. However, saturated fatty acid (SFA) increased ( p < 0.01) and polyunsaturated fatty acid (PUFA) decreased ( p < 0.05) when ME was decreased by 0.42 MJ/kg in growing-finishing pig diets. In addition, monounsaturated fatty acid (MUFA) tended to increase when CP level was decreased in growing-finishing pig diets ( p = 0.06). A growing-finishing diet of 13.82 MJ/kg diet of ME with the high CP level can improve growth performance and show better fatty acids composition of pork.

Dietary Energy Level Impacts the Performance of Donkeys by Manipulating the Gut Microbiome and Metabolome

“…The results of this study demonstrated that feeding HE to donkeys enhanced the growth performance in terms of ADG and G/F. Similarly, Ge et al (19) demonstrated that broilers fed HE had greater G/F than the basal energy groups, while Fang et al (20) indicated that G/F decreased as the dietary metabolic energy level decreased over the entire experimental period. Moreover, Ahmad et al (21) found that G/F was significantly higher with an increased dietary energy level.…”

Black soldier fly larval meal in feed enhances growth performance, carcass yield and meat quality of finishing pigs

“…In the present study, BSFLM in feed resulted in better performance of finisher pigs than when fed with conventional feed based on FM. Full-fat BSFLM is rich in CP, amino acids and has a high fat content and thus provides a better source of protein and net energy required for a better growth performance in growing-finishing pigs (Crosbie et al, 2020;Fang et al, 2019;Nekrasov et al, 2018;Yu et al, 2019).…”

Effects of Replacing Medical Zinc Oxide with Different Ratios of Inorganic: Organic Zinc or Reducing Crude Protein Diet with Mixed Feed Additives in Weaned Piglet Diets

“…Consistently, previous studies also reported that the BUN concentration decreased with decreasing CP levels in the diet [ 15 , 61 ]. BUN is a metabolite of protein utilization and is used as an indicator to determine protein digestibility [ 62 ]. Low BUN concentrations are considered to indicate an improvement in protein utilization.…”