Efficacy and Metabolizable Energy Equivalence of an α-Amylase-β-Glucanase Complex for Broilers

Carbohydrases and Phytase in Poultry and Pig Nutrition: A Review beyond the Nutrients and Energy Matrix

This review aimed to clarify the mechanisms through which exogenous enzymes (carbohydrases and phytase) influence intestinal health, as well as their effects on the nutrients and energy matrix in diets fed to poultry and pigs reared under sanitary challenging conditions. Enzyme supplementation can positively affect intestinal microbiota, immune system, and enhance antioxidant status. Although enzymes have been shown to save energy and nutrients, their responses under sanitary challenging conditions are poorly documented. Immune system activation alters nutrient partitioning, which can affect the matrix values for exogenous enzymes on commercial farms. Notably, the carbohydrases and phytase supplementation under sanitary challenging conditions align with energy and nutritional valorization matrices. Studies conducted under commercial conditions have shown that matrices containing carbohydrases and phytase can maintain growth performance and health in poultry and pigs. However, these studies have predominantly focused on assessing a single level of reduction in energy and/or available phosphorus and total calcium, limiting our ability to quantify potential energy and nutrient savings in the diet. Future research should delve deeper into determining the extent of energy and nutrient savings and understanding the effects of alone or blended enzymes supplementation to achieve more specific insights.

Optimization of exogenous carbohydrases supplemented in broiler diets using in vitro simulated gastrointestinal digestion and response surface methodology

The present study aimed to explore the optimal zymogram of combination of 6 carbohydrases (glucoamylase, pullulanase, maltase, thermostable α-amylase, medium temperature α-amylase, and cold-active α-amylase) supplemented in corn-soybean based diet of broilers aged 1 to 3 wk for the maximum starch digestibility, by using in vitro simulated gastrointestinal digestion and response surface method. The third generation of simulated monogastric animal digestion system was used for in vitro digestion experiment. By using single factor completely random design, the optimal supplement levels of single carbohydras were determined by the reducing sugar release amount and improved dry matter digestibility, which were the parameters representing the starch digestibility of the diet. Additionally, Box-Behnken response surface method was used to predict the optimal combination of 6 carbohydrases. The results showed that the optimistic zymogram of 6 carbohydrases in corn-soybean based diet for broilers aged 1 to 3 wk were 297.39 U/g glucoamylase, 549.72 U/g pullulanase, 3.01 U/g maltase, 1,455.73 U/g thermostable α-amylase, 278.64 U/g medium temperature α-amylase, and 1,985.97 U/g cold-active α-amylase, and the associated reduced sugar release amount and improved dry matter digestibility were 215.98 mg/g, and 6.23%, respectively. Furthermore, we conducted in vitro digestion experiments with diets supplemented with the predicted optimistic zymogram and found that the experimental reduced sugar release amount and improved dry matter digestibility were 219.26 mg/g and 6.31% respectively, whose errors to the predicted optimistic reducing sugar release amount and the improved dry matter digestibility were 1.05% and 1.02%. To sum up, the predicted optimal zymogram of 6 carbohydrases in the present study were capable to improve the starch digestibility in diet for broilers aged 1 to 3 wk, which were represented by increased reduced sugar release amount and improved dry matter digestibility.

Optimizing cost, growth performance, and nutrient absorption with a bio-emulsifier based on lysophospholipids for broiler chickens

Two experiments (Exp.) were conducted to evaluate effects of a lysophospholipid-based bio-emulsifier (LPL) on growth performance, nutrient digestibility and energy utilization of broilers as well as the return on investment (ROI). In Exp. 1, 392 chicks were housed in battery cages in a completely randomized design with 8 treatments and 7 replicates of 7 birds each from d 0 to 21 posthatch. In Exp. 2, 1,400 chicks were allocated in floor pens and fed the same 8 treatments, with 7 replicates and 25 birds each from d 0 to 43 posthatch. Treatments consisted of 6 degummed soybean oil-based diets: positive control (PC1); PC1 formulated with 500 g/ton LPL (PC1+LPL on top); PC1 formulated with 60 kcal LPL matrix (PC1+LPL60); PC1 formulated with 100 kcal LPL matrix (PC1+LPL100); and two negative controls NC-60 and NC-100 with reductions of 60 and 100 kcal/kg ME, respectively. Two other diets were formulated with acid soybean oil: positive control (PC2) and PC2 formulated with 60 kcal LPL matrix (PC2+LPL60). In Exp. 1, performance was evaluated from d 0 to 21, ME and ileal digestibility of DM, CP and energy were determined on d 21. In Exp. 2, growth performance was evaluated from d 0 to 42, and on d 43 carcass and abdominal fat yields were calculated. There were no effects of soybean oil sources in any parameter. Inclusion of LPL increased (P < 0.05) BW gain and ileal digestibility of DM, fat and CP. Broilers fed the PC1+LPL on top diet had increased (P < 0.05) performance, ileal digestibility and energy utilization as well as decreased abdominal fat compared to NC-60 or NC-100. The use of LPL on top had a ROI of 8:1 vs. PC1, considering the gains in revenue of the slaughtered broilers in relation to the investment with LPL in feed. In conclusion, a lysophospholipid-based bio-emulsifier increased performance, digestibility and return on investment of broilers fed standard or reformulated diets.

Intestinal starch and energy digestibility in broiler chickens fed diets supplemented with α-amylase

Dietary starch is the major energy source for broiler chickens; therefore, relevant information on its intestinal utilization is important. The present study was designed to evaluate intestinal starch and energy digestibility of broiler chickens fed diets supplemented with α-amylase. A total of 240 day-0 male broiler chicks were randomly assigned to 3 nutritionally adequate corn-soybean-based experimental diets comprising 3 levels of α-amylase supplementation (0, 80, or 160 KNU/kg diet). Each treatment comprised 8 replicate cages of 10 birds each. At day 21 after hatching, digesta was collected from 4 intestinal sites: the anterior jejunum (AJ), posterior jejunum (PJ), anterior ileum (AI), and posterior ileum. Increasing α-amylase supplementation linearly improved (P < 0.01) overall BW gain and feed efficiency of the birds. There were linear and quadratic (P < 0.01) responses of increasing α-amylase supplementation on starch and energy digestibility at the PJ and AI. The total tract digestibility of starch increased (P < 0.05) with increasing α-amylase supplementation. Starch disappearance and digestible energy (kcal/kg) linearly increased (P < 0.01) with digesta flow from the AJ to PJ as dietary α-amylase supplementation increased. There were linear (P < 0.01) and quadratic (P < 0.05) effects of increasing α-amylase supplementation on the villus height in the jejunum. The viscosity of the jejunal digesta decreased (P < 0.05) with increasing dietary α-amylase supplementation. The results from this study showed the efficacy of exogenous amylase in improving growth performance and starch and energy digestibility in broiler chickens. Furthermore, the digestibility of starch and energy and the impact of the exogenous amylase were higher at the PJ than other intestinal sites.

Growth phase and dietary α-amylase supplementation effects on nutrient digestibility and feedback enzyme secretion in broiler chickens

Growth performance, nutrient digestibility, intestinal health, and endogenous enzyme secretion responses to dietary α-amylase supplementation during 4 growth phases of broiler chickens fed corn–soybean meal–based diets were evaluated in the present study. A total of 1,136 male broiler chicks were assigned at day 0 after hatching to 8 treatments in a 2 × 4 factorial arrangement. There were 2 dietary levels of α-amylase supplementation of 0 or 80 kilo-Novo alpha amylase units per kg diet and 4 posthatching growth phases of day 0 to 11, day 11 to 21, day 21 to 42, or day 42 to 56 in a randomized complete block design. Each treatment comprised 8 replicate pens, with either 25 (day 0–11), 20 (day 11–21), 16 (day 21–42), or 10 (day 42–56) birds per pen. Body weight gain and feed efficiency of birds improved (P < 0.01) with α-amylase supplementation. There were main effects of α-amylase, growth phase, and interaction (P < 0.01) on apparent ileal digestibility (AID) of starch. This ranged from 0.8% during day 11 to 21 to 2.8% during day 0 to 11 after hatching. The total tract retention of starch increased (P < 0.05) with amylase supplementation but was not different across growth phases. Amylase supplementation increased (P < 0.05) AID of gross energy, AME (kcal/kg), and AMEn (kcal/kg). Villus height in the jejunal tissue was increased (P < 0.01) by α-amylase supplementation. During day 11 to 21 after hatching, the viscosity of jejunal digesta and pancreatic amylase activity increased (P < 0.01) with amylase supplementation. In conclusion, dietary amylase supplementation improved growth performance, apparent nutrient digestibility, and digestive enzyme activity of broiler chickens fed a corn–soybean diet. The study indicates that the growth phase of birds may affect response to exogenous amylase.

Utilization of corn-based diets supplemented with an exogenous α-amylase for broilers

A study was conducted to evaluate the effects of a supplemental α-amylase on energy and nutrient utilization of broiler chickens fed diets with variable amounts of corn. A total of 480 slow feathering Cobb × Cobb 500 male broilers were randomly distributed into 10 treatments with 8 replicates of 6 birds each. Birds were fed a common starter to 14 D post-hatch. The experimental diets were provided subsequently until 25 D, which were a conventional corn-soy basal diet (CS) and a corn-soy diet displaced with 40% of corn (CN). These were fed as-is or supplemented with 40, 80, 120, or 160 kilo-Novo α-amylase units (KNU)/kg. Dietary treatments were distributed factorially as a 2 × 5 arrangement (diet type vs. amylase). Samples of feed, excreta, and ileal digesta were analyzed for determination of ileal digestible energy (IDE), ME, total tract retention, and digestibility of dry matter, protein, and fat. No interactions between diet type and amylase were observed. The CN diet had lower (P < 0.05) energy utilization and nutrient digestibility when compared to the CS diet. AMEn and IDE increased (P < 0.05) by 110 and 207 kcal/kg, respectively, when CS and CN diets were supplemented with 80 KNU/kg. The amylase added to the CS diet led to quadratic increases (P < 0.05) on growth performance, IDE, AME, and AMEn, as well as in dry matter, protein, and fat digestibility. Energy utilization and crude protein digestibility were linearly increased (P < 0.05) when amylase was added to the CN diet or the extrapolated 100% of corn. In conclusion, energy utilization, digestibility of crude protein, fat, and dry matter increased with amylase supplementation in corn-soy-based diets. When amylase was tested in a complete diet having 53.6% corn, 100 and 105 KNU/kg maximized AMEn and IDE, respectively; however, the maximum energy response in the CN diet or 100% of corn was not achieved until 160 KNU/kg, suggesting an association between amylase dose optimization and dietary starch concentration.

Growth performance and carcass yield of broiler chickens in response to carbohydrases and its association with phytase

ABSTRACT An experiment was conducted to evaluate broiler chicken performance and carcass yield in response to carbohydrase supplementation (Xylanase and Betaglucanase; XB) and association of carbohydrase and phytase (PHY). A total of 1,920 day-old male broiler chicks (Cobb 500) were distributed in a completely randomized design with 8 treatments and 8 replicates each, allocated in 64 pens with 30 chicks each. The treatments were: Positive Control (PC); Negative Control (NC): reduced ME [-120kcal/kg (Starter) and -170kcal/kg (Finisher)]; NC + XB [50g/ton]; NC + XB [100g/ton]; NC + XB [150g/ton]; NC + XB [50g/ton] + PHY [100g/ton]; NC + XB [100g/ton] + PHY [100g/ton]; NC + XB [150g/ton] + PHY [100g/ton]. The inclusion of XB (150) and XB (50, 100, and 150) associated with phytase increased feed intake than positive control when considering the total rearing phase. The feed conversion ratio of all broilers fed diets with energy reduction were worse than positive control, even with the addition of enzymes, and did not differ between them. There was no significant effect of treatments on carcass parameters.

Energy and nutrient utilization of broiler chickens fed corn-soybean meal and corn-based diets supplemented with xylanase

A study was conducted to evaluate the effects of increased levels of a β-xylanase on energy and nutrient utilization of broiler chickens fed corn-soy diets. A total of 480 slow feathering Cobb × Cobb 500 male broilers were randomly distributed to 10 treatments having 8 replicates of 6 birds each. Birds were fed a common starter diet to d 14 post hatch (3,050 kcal/kg AMEn, 21.7% CP, 1.05% Ca, and 0.53% nPP). The experimental diets were provided afterwards until 25 d. Two experimental diets, a conventional corn/soy-based basal diet (CS) and the basal diet in which 40% of the diet was displaced by corn (CN), were fed as-is or supplemented with 50, 100, 150, or 200 fungal β-xylanase units (FXU)/kg. Dietary treatments were distributed factorially as a 2 × 5 arrangement. Samples of feed, excreta, and ileal digesta were analyzed for determination of ileal digestible energy (IDE), metabolizable energy, and total tract retention of protein and lipid. No interactions between diet and xylanase were observed. The CS diets had higher (P < 0.05) energy utilization and nutrient digestibility when compared to the CN diets. AMEn and IDE were improved (P < 0.05) by 192 and 145 kcal/kg, respectively, when diets were supplemented with 100 FXU/kg xylanase. The xylanase added to the CN diet led to quadratic increases (P < 0.05) in IDE (Y = - 0.014x(2) + 2.570x + 3,155; r(2) = 0.60) and in AMEn (Y = - 0.016x(2) + 3.982x + 3,155; r(2) = 0.68). Crude protein digestibility and AMEn were linearly increased (P < 0.05) when xylanase was added to the CN diet. In conclusion, energy utilization and digestibility of crude protein and dry matter increased with xylanase supplementation in corn/soy-based diets. When xylanase was tested in the CS diet, 92 and 124 FXU/kg maximized the energy release effect; however, the maximum energy response in the CN diet or corn was not achieved until 200 FXU/kg.