The effect of microbial phytase supplementation of sorghum-canola meal diets with no added inorganic phosphorus on growth performance, apparent total-tract phosphorus, calcium, nitrogen and energy utilization, bone measurements, and serum variables of growing and finishing swine

Effects of adding high-dosing Aspergillus oryzae phytase to corn-wheat-soybean meal-based basal diet on growth performance, nutrient digestibility, faecal gas emission, carcass traits and meat quality in growing-finishing pigs

This study tests the effects of supplementation of high-dosing Aspergillus oryzae phytase into the corn-wheat-soybean meal (SBM)-based basal diet on growth performance, nutrient digestibility, faecal gas emission, carcass traits and meat quality in growing-finishing pigs (29.73-110.86 kg live weight; 70-day-old to 166-day-old). A total of 56 crossbred pigs [(Landrace × Yorkshire) × Duroc] were divided into two dietary groups for a 96-day experiment (growing period, days 0-42; finishing period, days 43-96) with a completely randomized block design. There were seven replicate pens in each dietary group, and each pen has four pigs (two barrows and two gilts). The dietary treatments consisted of a corn-wheat-SBM-based nutrient sufficient basal diet or the basal diet supplemented with 1500 FTU/kg A. oryzae phytase. One phytase unit (FTU) was defined as the amount of enzyme that catalyses the release of one micromole phosphate from phytate/min at 37°C and pH 5.5. Higher average daily gain and lower feed conversion ratio were observed in growing-finishing pigs consuming a high-dosing A. oryzae phytase supplementing diet during days 0-42 and 0-96. Supplementing high-dosing A. oryzae phytase to the diet of growing-finishing pigs increased apparent total tract digestibility of phosphorus on days 42 and 96. Moreover, growing-finishing pigs fed the diet supplemented with high-dosing A. oryzae phytase had higher carcass back-fat thickness than those fed the control diet. However, the faecal gas emission and meat quality were not affected by high-dosing A. oryzae phytase supplementation. In conclusion, dietary supplementation of high-dosing A. oryzae phytase (1500 FTU/kg) had beneficial effects on the growth performance, apparent phosphorus digestibility and carcass back-fat thickness in growing-finishing pigs.

Effects of supplementation of high-dosing Trichoderma reesei phytase in the corn-wheat-soybean meal-based diets on growth performance, nutrient digestibility, carcass traits, faecal gas emission, and meat quality in growing-finishing pigs

We conduct this study to investigate the effects of corn-wheat-soybean meal (SBM)-based diet supplemented with high-dosing Trichoderma reesei phytase on the growth performance, nutrient digestibility, carcass traits, faecal gas emission and meat quality in growing-finishing pigs (29.71-110.58 kg live weight; 70-day-old to 166-day-old). A total of 56 crossbred pigs [(Landrace × Yorkshire) × Duroc] were used in 96-day experiment with a completely randomized block design. The growing period was from day 0 to 42, and the finishing period was from day 43 to 96. Pigs were randomly allocated to one of two treatments with seven replicate pens and four pigs (two barrows and two gilts) per pen and fed corn-wheat-SBM-based nutrient adequate basal diet or the basal diet supplemented with 1500 FTU/kg diet Trichoderma reesei phytase. One phytase unit (FTU) was defined as the amount of enzyme that catalyses the release of one micromole phosphate from phytate per minute at 37°C and pH 5.5. Dietary supplement with Trichoderma reesei phytase had increased body weight on day 96 and average daily gain in days 0-96. Moreover, high apparent total tract digestibility (ATTD) of phosphorus (P) was observed in pigs fed with Trichoderma reesei phytase. However, the carcass traits, faecal gas emission and meat quality of pigs were unaffected by Trichoderma reesei phytase supplementation. In conclusion, supplementation of high-dosing Trichoderma reesei phytase (1500 FTU/kg diet) in the corn-wheat-SBM-based nutrient adequate basal diet increased body weight and the ATTD of P, while no adverse effects were observed on the production characteristics.

Nutritional evaluation of different varieties of sorghum and the effects on nursery pig growth performance

Five experiments were conducted to determine the standardized total tract digestibility (STTD) of P, digestible energy (DE), metabolizable energy (ME), and standardized ileal digestibility (SID) of amino acids (AA) in three sorghum varieties compared with corn and to determine the effects of sorghum varieties on nursery pig growth. In exp. 1, 48 barrows (initially 18.6 kg) were housed individually in metabolism crates. Treatments were arranged in a 2 × 4 factorial evaluating two levels of microbial phytase (0 or 500 units/kg) and four grain sources (corn, high-lysine, red, or white sorghum). Added phytase improved (P < 0.05) STTD of P in all ingredients, but was not different among the grains. In exp. 2, the DE and ME in the three sorghum varieties were not different from corn. In exp. 3, 10 growing barrows (initially 25.9 kg) with a T-cannula in the terminal ileum were used. Standardized ileal digestible Lys, Met, Thr, and Val were greater (P < 0.05) in corn than in the sorghum-based diets with no differences among the sorghum varieties. In exp. 4, 160 pigs (initially 6.3 kg) were randomly allotted to one of four dietary treatments with five pigs per pen and eight replicate pens per treatment in a 20-d experiment. Dietary treatments included corn or the three sorghum varieties, where the varieties of sorghum replaced corn on an SID Lys basis. No differences among treatments were observed in any growth performance parameters. In exp. 5, treatments consisted of a corn-based diet, a diet based on conventional sorghum (a mixture of red and white sorghum), and four diets with high-lysine sorghum containing increasing amounts of feed-grade AA, replacing soybean meal. Overall, pigs fed the high-lysine sorghum diet with the greatest amount of added feed-grade AA had the poorest gain:feed ratio (G:F; P < 0.05) compared with pigs fed all the other experimental diets. Within those fed the high-lysine sorghum and feed-grade AA, average daily gain, final body weight (linear, P < 0.10), and G:F (linear, P < 0.01) decreased as feed-grade AA increased. In summary, no differences in STTD of P or in DE and ME were observed among the grain sources. The SID AA values for the three sorghum varieties were not different; however, they were all lower than for corn. These results indicate that these varieties of sorghum can successfully replace corn in nursery pig diets if diets are formulated to account for differences in AA digestibility.

Effect of microbial phytase supplementation on P digestibility in pigs: a meta-analysis

The objectives of this meta-analysis were to determine to which extent phosphorus (P) digestibility and digestible P concentration in pig diets were increased by phytase supplementation and to quantify factors that potentially influence effects of phytase supplementation. A data set with a total of 547 data lines was compiled from 88 experiments published in 74 peer-reviewed papers between 2007 and April 2019. An exponential model was determined as more suitable to describe the response of P digestibility to phytase supplementation than a polynomial model. Phytase supplementation increased P digestibility by 25.6 percentage points (standard error (SE) = 1.54) to a plateau at 64.9% (SE = 1.82). The digestible P concentration was increased by phytase supplementation in the order of 1.01 g/kg (SE = 0.102) to a plateau at 2.62 g/kg (SE = 0.122). Goodness-of-fit criteria were R² = 0.780 and root mean square error = 7.55% for P digestibility, and R² = 0.691 and root mean square error = 0.48 g/kg for digestible P concentration. Consideration of further factors such as mineral P supplementation (yes or no), ad libitum vs. restrictive feeding, mixed diets vs. single feed ingredients, sex and age of pigs did not increase the accuracy of prediction in this data set. Some of these traits exhibited responses, but they likely are artefacts generated through the imbalanced structure of the data set. Effects of dietary total P, phytate (InsP₆), InsP₆-P to total P ratio, and Ca on the effect of supplemented phytase were not quantifiable. The present meta-analysis showed that responses to phytase supplementation can be well predicted although variation in P digestibility and digestible P concentration in the data set was high. Overall, predicted effects of phytase on P digestibility well corresponded to predictions made 25 years ago.