The Effect of Reduced Crude Protein on Growth Performance, Nutrient Digestibility, and Meat Quality in Weaning to Finishing Pigs.

This study aimed to evaluate optimal crude protein (CP) levels based on the National Research Council guidelines from 1998 and 2012 and their impacts on growth performance, fecal score, blood profiles, nutrient digestibility, and carcass characteristics of weaning to finishing pigs. Four diets were established in this experiment: high-protein (HP), medium-high-protein (MHP), medium-low-protein (MLP), and low-protein (LP). The HP diet followed the NRC (1998) guidelines, while the MHP diet reduced the CP content by 1%. The MLP diet had 1.5% lower CP content than the HP diet. The LP diet followed the NRC guideline of 2012, which suggests less protein than the NRC guideline of 1998. There were no significant differences in body weight, average daily feed intake, or nutrient digestibility. However, the average daily gain (ADG) of pigs fed the LP diet at 7-10 weeks was lower than in the other treatments, whereas the ADG of the pigs fed the LP diet was higher compared with that of pigs fed the other diets, showing compensatory growth in finishing periods (p < 0.05). The blood urea nitrogen of pigs fed the LP diet showed the lowest value, whereas the highest value was found in pigs fed the HP diet, and the other two diets were similar to the HP diet or positioned between the HP and LP diets (p < 0.05). Water holding capacity, cooking loss, shear force, and pH in the longissimus muscle were not influenced by varying dietary CP levels (p > 0.05), but the hunter values L and b were increased in pigs fed the LP diet (p < 0.05). Conclusively, a low-protein diet did not negatively affect growth performance, nutrient digestibility, or meat quality.

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

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.

Effects of dietary energy and crude protein levels on growth performance, blood profiles, and nutrient digestibility in weaning pigs.

OBJECTIVE: This experiment was conducted to investigate the effect of reducing dietary metabolic energy (ME) and crude protein (CP) levels on growth performance, blood profiles, and nutrient digestibility in weaning pigs. METHODS: A total of 240 crossbred pigs (Duroc×[Landrace×Yorkshire]) with an average body weight of 8.67±1.13 kg were used for a 6-week feeding trial. Experimental pigs were allotted to a 2×3 factorial arrangement using a randomized complete block design. The first factor was two levels of dietary ME density (low ME level, 13.40 MJ/kg or high ME level, 13.82 MJ/kg) and the second factor was three dietary CP levels based on subdivision of early and late weaning phases (low CP level, 19.7%/16.9%; middle CP level, 21.7%/18.9%; or high CP level, 23.7%/20.9%). RESULTS: Over the entire experimental period, there were no significant difference in body weight among groups, but a decrease in diet energy level was associated with an increase in average daily feed intake (p = 0.02) and decrease in gain-feed ratio (G:F) ratio (p<0.01). Decreased CP levels in the diet were associated with a linear increase in average daily gain (p< 0.05) and quadratic increase in G:F ratio (p<0.05). In the early weaning period, blood urea nitrogen concentration tended to increase when ME in the diet decreased and decrease when CP level in the diet decreased (p = 0.09, p<0.01, respectively). Total protein concentration tended to increase when CP level was reduced (p = 0.08). In the late weaning period, blood urea nitrogen concentration decreased linearly as CP level decreased (p<0.01). The CP and crude fat digestibility decreased when ME was decreased by 0.42 MJ/kg (p = 0.05, p = 0.01, respectively). The CP digestibility increased linearly as CP level decreased (p = 0.01). CONCLUSION: A weaning pig diet containing high ME level (13.82 MJ/kg) and low CP level (19.7%/16.9%) can improve pig growth performance and nutrient digestibility.

Various levels of rapeseed meal in weaning pig diets from weaning to finishing periods.

OBJECTIVE: This experiment was conducted to investigate the influence of rapeseed meal (RSM) supplementation in weaning pig diet on growth performance, blood profile, carcass characteristics and economic analysis on weaning to finishing pigs. METHODS: A total of 120 cross bred ([Yorkshire×Landrace]×Duroc) weaning pigs were allotted to 5 treatments in a randomized complete block design. Each treatment had 4 replications with 6 pigs per pen. Five different levels of RSM (0%, 2%, 4%, 6%, and 8%) were used as dietary treatments. RESULTS: Overall, no treatment showed significant differences in growth performance with increased dietary RSM levels. The concentration of blood urea nitrogen (BUN) decreased as dietary RSM levels increased in 6 weeks (linear response, p<0.01). Total cholesterol, high density lipoprotein cholesterol, low density lipoprotein cholesterol, triiodothyronine, and thyroxine showed no significant differences, neither were there any significant differences in the immune response (IgG and IgA). As the dietary RSM levels of weaning pig diet were increased, no differences were found among dietary treatments upon performing proximate analyses of the pork after finishing. The influence of RSM supplementation on nutrient digestibility and nitrogen retention were not affected by dietary RSM levels either. With increased dietary RSM levels in the weaning pig diet, no differences among dietary treatments were found after performing proximate analyses of the pork's physiochemical properties. In addition, there were no significant differences observed in pork colors, pH levels, and economic benefits. CONCLUSION: Consequently, this experiment demonstrated that weaning pig's diet containing RSM influenced BUN concentration, but there were no detrimental effects on the growth performance of weaning pigs with up to 8% RSM in the diet.

Effects of wheat supplementation levels on growth performance, blood profiles, nutrient digestibility, and pork quality in growing-finishing pigs.

OBJECTIVE: This study was conducted to evaluate various wheat supplementation levels on growth performance, blood profiles, nutrient digestibility, and pork quality in growing-finishing pigs. METHODS: A total of 120 growing pigs ([Yorkshire×Landrace]×Duroc), with an average 27.75± 1.319 kg body weight, were used in growth trial. Pigs were allotted into each treatment by body weight and sex in 4 replicates with 6 pigs per pen in a randomized complete block design. Four-phase feeding programs were used in this experiment. The treatments included the following: i) corn-soybean meal (SBM) - based diet (CON), ii) corn-SBM - based diet+15% of wheat (W15), iii) corn-SBM - based diet+30% of wheat (W30), iv) corn-SBM - based diet+45% of wheat (W45), and 5) corn-SBM-based diet+60% of wheat (W60). RESULTS: There was no significant difference in growth performance among the dietary treatments. However, the gain-to-feed (G:F) ratio tended to increase (quadratic, p<0.08) when the pigs were fed a higher wheat diet during the finishing period. The digestibility of crude ash and fat tended to decrease as the wheat supplementation level increased (p<0.08). The proximate analysis of the longissimus muscle was not affected by the dietary level of wheat. The crude ash content in pork was decreased linearly as the wheat supplementation level increased (p = 0.05). There was no significant difference in the pH level, shear force, water holding capacity, and cooking loss of the pork. In pork and fat, L*, a*, and b* values were not significantly different among dietary treatments. CONCLUSION: Wheat can be supplemented up to 60% in a growing-finishing pig without detrimental effects on growth and pork quality. The G:F ratio tended to improve in the finishing period by wheat inclusion.

End point determination of blending process for trimebutine tablets using principle component analysis (PCA) and partial least squares (PLS) regression.

This study showed near Infrared (NIR) and Raman spectroscopy with a multivariate calibration approach were very effective to determine blend uniformity end-point. A set of 36 trimebutine samples containing magnesium stearate, stearic acid, colloidal silicon oxide, talc as excipients (0.9%∼1.8%) was acquired from six positions during blending processing with U-type blender from 0 to 30 min. Principle component analysis (PCA) with NIR and Raman spectral data was used to confirm the end-point of blending. After 30 min, the scores of principle component (PC) 1 and principle component (PC) 2 for samples moved into one point, which clearly indicated the mixture of sample became homogenous. In addition, NIR and Raman spectroscopy has been applied to the quantitative analysis of 20 trimebutine samples containing 2∼40% in mixture granules, which divided into a calibration set of 15 samples and a prediction set of 5 samples for NIR spectral data. The standard error of calibration (SEC) and standard error of prediction (SEP) are 0.15% and 0.13%, respectively using NIR while SEC and SEP of 0.95% and 0.91% are obtained using Raman spectroscopy. The results showed the NIR and Raman spectroscopy with a multivariate calibration such as PCA and PLS provide the possibility of real time monitoring of homogeneity and content uniformity during blending process.