Evaluation of multienzyme supplementation and fiber levels on nutrient and energy digestibility of diets fed to gestating sows and growing pigs.

The objective was to investigate the effect of a multienzyme blend (MEblend) and inclusion level on apparent total tract digestibility (ATTD) of energy and nutrients, as well as ileal digestibility of crude protein (CP) and amino acids (AA) in gestation diets with low (LF) or high-dietary fiber (HF) fed to gestation sows. For comparison, growing pigs were fed the same HF diets to directly compare ATTD values with the gestating sows. In experiment 1, 45 gestating sows (parity 0 to 5; 187 ±â€…28 kg bodyweight; BW) were blocked by parity in a 2 × 3 factorial arrangement and fed 2.2 kg/d of the HF (17.5% neutral detergent fiber; NDF) or LF (13% NDF) diet and one of three levels of MEblend (0.0%, 0.08%, and 0.1%) to determine impacts of MEblend on ATTD. Twenty-seven growing pigs (initial 35.7 ±â€…3.32 kg BW) were fed the same HF diet (5% of BW) and one of three MEblend inclusions. The MEblend at both 0.08% and 0.1% increased ATTD of energy, NDF, and acid detergent fiber (ADF) (P < 0.05) in gestating sows but ATTD of total non-starch polysaccharides (NSP) and its residues were not affected. Sows fed HF, regardless of MEblend, had greater ATTD of NDF, xylose, and total NSP (P < 0.05) in comparison to grower pigs. In experiment 2, ileal cannulas were placed in 12 gestating sows (parity 0 to 2; BW 159 ±â€…12 kg) to determine apparent and standardized ileal digestibility (AID and SID) of AA and NSP. In a crossover design, sows were fed the same six diets, as in experiment 1, and a nitrogen-free diet during five periods of seven days each to achieve eight replicates per diet. There was no interaction between diet fiber level and MEblend inclusion. Supplementation of MEblend to gestating sow diets did not impact SID of CP and AA regardless of dietary fiber level. The SID of His, Ile, Lys, Phe, Thr, Trp, and Val were 3% to 6% lower (P < 0.09) in HF than LF independent of MEblend. Supplementation of MEblend did not impact AID of NSP components, but sows fed HF had higher AID of arabinose (LF: 26.5% vs. HF: 40.6%), xylose (LF: 3.5% vs. HF: 40.9%), and total NSP (LF: 25.9% vs. HF: 40.0%) compared to sows fed LF (P < 0.05). Dietary supplementation of MEblend increased ATTD of nutrients, NSP, and energy in diets fed to gestating sows regardless of inclusion level, with MEblend having a greater incremental increase in diets with lower NDF levels. Inclusion of MEblend impacted neither SID of AA nor AID of NSP in low- or high-fiber gestation diets, but high-fiber diet, negatively affected SID of AA.

Fiber-degrading enzymes have been extensively studied in growing pigs with minimal studies focusing on gestating sows; however, commercial gestating sow diets often contain more fiber than grower pig diets to stimulate the sensation of satiety without influencing weight gain. A challenge with dietary fiber is its hindrance on digestibility of nutrients. Supplementation of multienzyme blends increases nutrient digestibility of fibrous diets in grower pigs, but there is little data characterizing the effects of fiber-degrading enzymes in gestation diets for pregnant sows. In this study, inclusion of a multienzyme comprised of various carbohydrases and a protease in gestation diets increased apparent total tract digestibility of nutrients and energy for both gestating sows and growing pigs; however, digestibility of non-starch polysaccharides was only improved in growing pigs. Enzyme supplementation to gestating sow diets had limited impact on the ileal digestibility of nutrients, but ileal digestibility of amino acids and crude protein was reduced when gestating sows were fed diets higher in neutral detergent fiber. When formulating high-fiber diets for gestating sows and growing pigs using similar ingredients, it is critical to consider the differences in digestibility of fibrous components, particularly regarding ileal digestibility of amino acids.

Nutrient digestibility of multi-enzyme supplemented low-energy and AA diets for grower pigs1.

A study was conducted to determine effects of supplementing multi-enzyme on apparent ileal digestibility (AID) of energy and AA; and apparent total tract digestibility (ATTD) of energy for pigs fed low-energy and AA diets. Eight ileal-cannulated barrows (initial BW: 38.7 ± 2.75 kg) were fed four diets in a replicated 4 × 4 Latin square design to give 8 replicates per diet. Diets were positive control (PC) diet, negative control (NC) diet without or with multi-enzyme at 0.5 or 1.0 g/kg. The PC diet was formulated to meet or exceed NRC (2012) nutrient recommendations for grower pigs (25 to 50 kg), except for Ca and digestible P, which were lower than NRC (2012) recommendations by 0.13 and 0.17 percentage points, respectively, due to phytase supplementation at 1,000 FTU/kg. The NC diet was formulated to be lower in NE by 75 kcal/kg and standardized ileal digestible AA content by a mean of 3%. These reductions were achieved by partial replacement of corn and soybean meal (SBM) and complete replacement of soybean oil and monocalcium phosphate in PC diet with 25% corn distillers dried grains with solubles (DDGS) and 3.6% soybean hulls. Multi-enzyme at 1.0 g/kg supplied 1,900 U of xylanase, 300 U of ß-glucanase, 1,300 U of cellulase, 11,500 U of amylase, 120 U of mannanase, 850 U of pectinase, 6,000 U of protease, and 700 U of invertase per kilogram of diet. The AID of GE, N, most AA, most component sugars of nonstarch polysaccharides (NSP) and P; ATTD of GE for PC diet was greater (P < 0.05) than those for NC diets. An increase in dietary level of multi-enzyme from 0 to 1.0 g/kg resulted in a linear increase (P < 0.05) in AID of Ile by 4.3%, and tended to linearly increase (P < 0.10) AID of Leu, Met, Phe, and Val by a mean of 3.4%. Increasing dietary multi-enzyme from 0 to 1.0 g/kg linearly increased (P < 0.05) AID of total NSP and P by 53.7% and 19.2%, respectively; ATTD of GE by 8.4% and DE and NE values by 8.8% and 8.2%, respectively; tended to linearly increase (P < 0.10) AID of GE by 8.1%. The NE values for NC diet with multi-enzyme at 1.0 g/kg tended to be greater (P < 0.10) than that for PC diet (2,337 vs. 2,222 kcal/kg of DM). In conclusion, multi-enzyme supplementation improved energy and nutrient digestibilities of a corn-SBM-corn DDGS-based diet, implying that the multi-enzyme fed in the current study can be used to enhance energy and nutrient utilization of low-energy AA diets for grower pigs.

Effect of microwave treatment on the efficacy of expeller pressing of Brassica napus rapeseed and Brassica juncea mustard seeds.

A study was conducted to evaluate the effect of microwave heating on the efficacy of expeller pressing of rapeseed and mustard seed and the composition of expeller meals in two types of Brassica napus rapeseed (intermediate- and low-glucosinolate) and in Brassica juncea mustard (high-glucosinolate). Following microwave treatment, the microstructure of rapeseed using transmission electron microscopy showed a significant disappearance of oil bodies and myrosin cells. After 6 min of microwave heating (400 g, 800 W), the oil content of rapeseed expeller meal decreased from 44.9 to 13.5% for intermediate-glucosinolate B. napus rapeseed, from 42.6 to 11.3% for low-glucosinolate B. napus rapeseed, and from 44.4 to 14.1% for B. juncea mustard. The latter values were much lower than the oil contents of the corresponding expeller meals derived from the unheated seeds (i.e., 26.6, 22.6, and 29.8%, respectively). Neutral detergent fiber (NDF) contents showed no differences except for the expeller meal from the intermediate-glucosinolate B. napus rapeseed, which increased from 22.7 to 29.2% after 6 min of microwave heating. Microwave treatment for 4 and 5 min effectively inactivated myrosinase enzyme of intermediate-glucosinolate B. napus rapeseed and B. juncea mustard seed, respectively. In low-glucosinolate B. napus rapeseed the enzyme appeared to be more heat stable, with some activity being present after 6 min of microwave heating. Myrosinase enzyme inactivation had a profound effect on the glucosinolate content of expeller meals and prevented their hydrolysis to toxic breakdown products during the expelling process. It appeared evident from this study that microwave heating for 6 min was an effective method of producing expeller meal without toxic glucosinolate breakdown products while at the same time facilitating high yield of oil during the expelling process.

Low-fiber canola. Part 1. Chemical and nutritive composition of the meal.

The objective of the current study was to evaluate the chemical and nutritive composition of meals derived from a newly developed yellow-seeded Brassica napus canola and the canola-quality Brassica juncea . In comparison with its conventional black-seeded counterpart, meal derived from yellow-seeded B. napus canola contained more protein (49.8 vs 43.8% DM), more sucrose (10.2 vs 8.8% DM), and less total dietary fiber (24.1 vs 30.1% DM). B. juncea canola showed intermediate levels of protein, sucrose, and dietary fiber (47.4, 9.2, and 25.8%, respectively). The reduction in fiber content of yellow-seeded B. napus canola was a consequence of a bigger seed size, a lower contribution of the hull fraction to the total seed mass, and a lower content of lignin with associated polyphenols of the hull fraction. The meal derived from yellow-seeded B. napus canola would appear to have quality characteristics superior to those from black-seeded B. napus or yellow-seeded B. juncea.

Low-fiber canola. Part 2. Nutritive value of the meal.

The nutritive value of meals derived from black- and yellow-seeded Brassica napus and canola-quality Brassica juncea was determined with broiler chickens and young turkeys. A higher apparent ileal digestibility of total amino acids was observed in chickens fed diet containing yellow-seeded B. napus than in those fed conventional black-seeded B. napus or canola-quality B. juncea (88.8 vs 83.4 and 84.2%, P < 0.05). Metabolizable energy (AME(n)) contents for yellow- and black-seeded B. napus and B. juncea as determined with broiler chickens were 2190, 1904, and 1736 kcal/kg DM, respectively. In the turkey assay, the AME(n) values for yellow- and black-seeded B. napus and B. juncea canola averaged 2166, 2007, and 1877 kcal/kg DM, respectively. Multicarbohydrase enzyme addition to broiler chicken diets increased energy utilization (from 1943 to 2249 kcal/kg DM, on average), with the most pronounced effect observed for B. juncea canola (from 1736 to 2356 kcal/kg DM).