This study was conducted to determine and compare digestible energy (DE) and metabolizable energy (ME) values and the apparent total tract digestibility (ATTD) of energy and nutrients in eight ingredients fed to both growing pigs and sows. Two experiments with 48 crossbred barrows or six non-pregnant sows were allotted to eight treatments in a completely randomized design or a pseudo Latin square with six replicated pigs per dietary treatment. The dietary treatments were formulated with two cereal ingredients: corn and wheat; two ingredients with a high protein level and a low fiber level (HPLF): soybean meal (SBM) and cottonseed meal (CSM); two ingredients with medium protein level and medium fiber level (MPMF): corn distiller’ dried grains with solubles (DDGS) and corn germ meal (CGM); and two ingredients with a low protein level and a high fiber level (LPHF): wheat bran (WB) and palm kernel meal (PKM), respectively. Adult sows had greater DE and ME values and ATTD of energy and nutrients when fed cereal ingredients compared with growing pigs, and had lower DE and ME contents and ATTD of energy and nutrients except for acid detergent fiber (ADF) when fed HPLF ingredients compared with growing pigs. Moreover, no differences were observed between adult sows and growing pigs in DE and ME contents and ATTD of energy and nutrients when fed MPMF and LPHF ingredients, except that adult sows showed a greater ATTD of crude protein (CP) when fed MPMF ingredients compared with growing pigs. Our results indicate that sows had a lower available energy and nutrient digestibility when fed SBM or CSM compared with growing pigs. Crude protein contents in ingredients should be considered when predicting DE and ME values in sows based on the DE and ME values measured from growing pigs.

Objective: The objective of this experiment was to determine the net energy (NE) value of 6 wheat bran and 1 wheat shorts by indirect calorimetry and establish the NE prediction equations of wheat bran fed to growing barrows.Methods: Forty-eight growing barrows (28.5±2.4 kg body weight) were allotted in a completely randomized design to 8 dietary treatments that included a corn-soybean meal basal diet, 6 wheat bran diets and 1 wheat shorts diet. The inclusion level of wheat bran or wheat shorts in diets is 30%.Results: The addition of wheat bran reduced the apparent total tract digestibility (ATTD) of nutrients (p<0.05). The ATTD of gross energy, crude protein (CP) and dry matter (DM) in the wheat shorts were greater than that in the wheat bran. Addition of wheat bran or wheat shorts had no effect on total heat production and fasting heat production. The NE of wheat bran was negatively correlated with neutral detergent fiber (r = –0.84; p<0.05) and acid detergent fiber (r = –0.83; p<0.05), while it was positively correlated with CP (r = 0.92; p<0.01). The NE values of wheat bran ranged from 6.79 to 8.15 MJ/kg DM, and the NE value of wheat shorts was 12.47 MJ/kg DM. The ratio of NE to metabolizable energy for wheat bran fed to growing pigs was from 66.0% to 71.7%, whereas the value for wheat shorts was 83.7%.Conclusion: The NE values of wheat bran ranged from 6.79 to 8.15 MJ/kg DM, and the NE value of wheat shorts was 12.47 MJ/kg DM. The NE value of wheat bran can be well predicted based on energy content and proximate analysis.

The objective of this experiment was to investigate the effects of reduced dietary protein at natural high temperature in summer on the growth performance and carcass quality of finishing pigs. A total of 72 crossbreed pigs (Duroc × Landrace × Yorkshire) at an average body weight (BW) of 77 ± 5.7 kg were randomly assigned to two treatments, based on BW and sex, in six replicates per treatment, with six pigs per pen, using a randomized complete block design. The dietary crude protein (CP) level of the normal protein diet (NP) and the reduced protein diet (LP) were 12% and 10%, respectively. The growth performance and serum biochemical parameters of the pigs were analyzed for a 28-day experimental period. At the end of the experiment, 12 pigs were harvested to measure carcass characteristics and pork quality. The average highest ambient temperature during the experiment period was about 32.4 °C. There was a trend for the average daily feed intake (ADFI) to be lower in the pigs on the reduced protein diet compared to the control (p < 0.10) in the 0–28 day period. The serum urea nitrogen was lower (p < 0.05) for pigs fed the reduced protein diets only on day 14. The carcass characteristics and pork quality were not affected by dietary treatments. In conclusion, decreasing dietary crude protein percentage from 12% to 10% in finishing pigs in summer may have no negative effects on growth performance and carcass quality.

The purpose of this study was to explore the effects of xylose with different polymerizations on growth performance, intestinal barrier function, and gut microbial composition in weaned piglets. A total of 144 weaned piglets were assigned to 3 dietary treatments in a completely randomized design according to their body weight and sex. Dietary treatments included a corn-soybean meal basal diet (CON) and 2 additional diets formulated with 1% arabinoxylan (AX) and 1% xylo-oligosaccharide (XOS), respectively. Results showed that dietary supplementation of XOS or AX reduced diarrhea incidence of weaned piglets compared with the CON group (p < 0.05). XOS or AX increased the ileal villus height and intestinal activity of antioxidases in weaned piglets compared with the CON group (p < 0.05). XOS or AX reduced the ileal and colonic IL-6 content and increased the colonic sIgA and IL-10 concentrations in weaned piglets compared with the CON group (p < 0.05). XOS or AX increased the total organic acids concentrations in the ileum and in vitro fermentation (p < 0.05). XOS increased the abundance of Lactobacillus and Bifidobacterium in the ileal digesta (p < 0.05), while AX increased the population of Lactobacillus in the ileal digesta and the abundance of Bifidobacterium in the colonic digesta of weaned piglets (p < 0.05). In conclusion, both XOS and AX reduce diarrhea incidence and improve antioxidant capacity, immune function, and populations of beneficial bacteria, while microbial fermentation of XOS with a lower polymerization and molecular mass can produce more organic acids and an increased abundance of Lactobacillus and Bifidobacterium in the upper gut of weaned pigs compared with AX.

Two experiments were conducted to evaluate tetrabasic zinc chloride (TBZC) on the health of weaned pigs, and to determine the optimal supplemental concentrations and whether dietary TBZC could replace the pharmacological concentrations of dietary zinc oxide (ZnO) to improve growth performance and decrease Zn excretion in weaned pigs. In Exp. 1, 180 weaned pigs (8.92 ± 1.05 kg BW) were randomly assigned to 1 of 5 treatments, including the basal diet containing 125 mg/kg zinc sulfate (ZnSO4), and the basal diet with 1,200, 1,800, 2,400, or 3,000 mg/kg TBZC supplementation. In Exp. 2, 240 weaned pigs (7.66 ± 1.09 kg BW) were randomly assigned to 1 of 5 treatments, including a negative control diet without Zn supplementation (NC), a positive control diet (2,250 mg/kg ZnO), and 3 experimental diets with different concentrations of TBZC supplementation (1,000, 1,250 and 1,500 mg/kg). In Exp. 1, the average daily gain (ADG), feed efficiency (G:F) and diarrhea incidence responded quadratically (p<0.01) as the TBZC supplemental concentrations increased, and pigs fed 1,200 and 1,800 mg/kg TBZC showed the best growth performance. Moreover, 1,800 mg/kg TBZC supplementation showed the greatest (p<0.01) total antioxidant capacity (T-AOC) and glutathione peroxidase (GSH-Px) activities in liver of pigs. Histopathological examination revealed lesions in heart, liver, lung and kidney, and mild or severe histological lesions mainly occurred with the supplementation of 2,400 and 3,000 mg/kg TBZC. In Exp. 2, 1,000 and 1,250 mg/kg TBZC supplementation in diets significantly (p<0.01) increased ADG and G:F of weaned pigs, reduced Zn excretion in feces, and had no effect on diarrhea-reducing compared to 2,250 mg/kg ZnO supplementation. TBZC is a potential alternative to ZnO. The recommended concentration of TBZC in weaned pig diets is 1,000 to 1,250 mg/kg.

Objective: The study was conducted to determine the effects of body weight (BW) and fiber sources on nutrient digestibility, fiber fermentation and short chain fatty acids (SCFA) concentration in different intestinal segments of growing pigs fed high-fiber diets.Methods: Nine barrows with initial BW of 25.17±0.73 kg and 9 barrows with initial BW of 63.47±2.18 kg were allotted to a duplicate 9×2 Youden Square design with 3 dietary treatments and 2 periods. The dietary treatments were formulated with 3 different high-fiber ingredients: corn bran, sugar beet pulp, and soybean hulls, respectively. Each diet was fed to 3 barrows with different stage of BW in each period.Results: There were no differences in the apparent ileal digestibility (AID) of most nutrients between pigs at different BW stages. Pigs at 60 kg had greater (p<0.05) apparent total tract digestibility (ATTD) of total dietary fiber (TDF), soluble dietary fiber (SDF) and insoluble dietary fiber (IDF), and had greater (p<0.05) hindgut disappearance of IDF and cellulose than pigs at 25 kg. The acetate, propionate and total SCFA concentrations in ileal digesta and feces of pigs at 60 kg were greater (p<0.05) than those of pigs at 25 kg. In addition, fiber sources affected (p<0.05) the AID of gross energy (GE), organic matter (OM), ether extract (EE), crude protein, SDF and hemicellulose, the hindgut disappearance and ATTD of dietary fiber components, the lactate and propionate concentrations in ileal digesta and the butyrate, valerate and total SCFA concentrations in feces. There were interactions (p<0.05) between BW and fiber sources on the AID of GE, OM, EE, SDF, hemicellulose, the ATTD of EE, TDF, and IDF, and the hindgut disappearance of SDF and hemicellulose.Conclusion: Increasing BW mainly improved the digestibility of dietary fiber fractions, and the dietary fiber sources influenced the digestibility of almost all the dietary nutrients in growing pigs.