Isolation and Characterization of Mannanase-Producing Bacteria for Potential Synbiotic Application in Shrimp Farming

Prebiotics such as mannan-oligosaccharides (MOS) are a promising approach to improve performance and disease resistance in shrimp. To improve prebiotic utilization, we investigated the potential probiotics and their feasibility of synbiotic use in vitro. Two bacterial isolates, Man26 and Man122, were isolated from shrimp intestines and screened for mannanase, the enzyme for mannan digestion. The crude mannanase from both isolates showed optimal activities at pH 8 with optimum temperatures at 60 °C and 50 °C, respectively. The enzymes remained stable at pH 8−10 for 3 h (>70% relative activity). The thermostability range of Man26 was 20−40 °C for 20 min (>50%), while that of Man122 was 20−60 °C for 30 min (>50%). The Vmax of Man122 against locust bean gum substrate was 41.15 ± 12.33 U·mg−1, six times higher than that of Man26. The Km of Man26 and Man122 were 18.92 ± 4.36 mg·mL−1 and 34.53 ± 14.46 mg·mL−1, respectively. With the addition of crude enzymes, reducing sugars of copra meal, palm kernel cake, and soybean meal were significantly increased (p < 0.05), as well as protein release. The results suggest that Man26 and Man122 could potentially be used in animal feeds and synbiotically with copra meal to improve absorption and utilization of feedstuffs.

Energy values of copra meal and cornstarch for broiler chickens

Two studies were conducted with broiler chickens to determine the ileal digestible energy (IDE), ME, and MEn in copra meal (CM) and cornstarch using the regression method. On day 15 and 16 for experiments 1 and 2, respectively, 192 male birds were individually weighed and allotted into 3 dietary treatments with 8 replicate cages and 8 birds per cage in a randomized complete block design with the BW as a blocking factor in each experiment. Dietary treatments consisted of 3 inclusion levels of test ingredients (i.e., 0, 100, or 200 g/kg) in corn-soybean meal-based diets using CM or cornstarch as test ingredients for experiment 1 or 2, respectively. Titanium dioxide was added as an indigestible marker to determine the ileal digestibility and utilization of energy by the index method. Experiments lasted 5 d, and excreta collection was conducted during the last 3 d of each experiment. At the end of experiments, birds were euthanized by CO2 asphyxiation, and ileal digesta samples were collected. Data were analyzed by the ANOVA using the GLM procedure. In experiment 1, the apparent ileal digestibility (AID) of DM and gross energy (GE) and IDE in test diets linearly decreased (P < 0.05) with substitution of CM in test diets. In experiment 2, there were quadratic increases (P < 0.01) in the AID of DM and GE and IDE in diets as the concentration of cornstarch in test diets increased. In addition, linear increases (P < 0.05) in the apparent total tract utilization of DM, N, and GE and ME and MEn in test diets were observed. The estimates of IDE, ME, and MEn in CM were 2,493, 3,727, and 3,546 kcal/kg DM, respectively, whereas respective values of cornstarch were estimated at 4,181, 3,992, and 3,946 kcal/kg DM, respectively. In conclusion, inclusion of CM in diets may reduce the digestibility of GE, whereas the digestibility and utilization of GE may increase when adding cornstarch into diets for broiler chickens.

Effects of Copra Meal Inclusion Level in Growing-Finishing Pig Diets Containing β-Mannanase on Growth Performance, Apparent Total Tract Digestibility, Blood Urea Nitrogen Concentrations and Pork Quality

Simple Summary

The increasing demand and production of ethanol have led to an increase in corn price, which has resulted in increased animal feed cost. Alternative feed ingredients such as copra meal have attracted great attention in the feed and swine industry due to their comparable nutritional values and price compared to conventional swine feed ingredients, such as corn and soybean meal. The current study aims at demonstrating the effect of copra meal inclusion with β-mannanase on growth performance, nutrient digestibility, blood urea nitrogen concentrations, and pork quality of growing-finishing pigs. Our result suggested that copra meal could have the potential to be used in the swine diets up to 12% when the diets were supplemented with 800 IU of β-mannanase per kg diet.

Abstract

This experiment was conducted to evaluate the effects of copra meal (CM) inclusion level on the growth performance, apparent total tract digestibility (ATTD), blood urea nitrogen (BUN) concentrations, and pork quality of growing-finishing pigs fed diets containing β-mannanase. Eighty crossbred pigs with average body weight (BW) of 27.22 ± 0.09 kg were allotted to five dietary treatments with four pigs per pen and four replicates per treatment based on sex and BW. The dietary treatments were: (1) NC: negative control, corn-soybean meal (SBM) based basal diet, (2) PC: positive control, basal diet + 0.10% β-mannanase (800 IU/ kg diet), (3) CM6: PC diet with 6% CM inclusion, (4) CM12: PC diet with 12% CM inclusion, and (5) CM18: PC diet with 18% CM inclusion in a three-phase feeding program (growing: 0–6 weeks, finishing I: 7–9 weeks, and finishing II: 10–12 weeks). The quadratic responses were observed in the BW at six weeks (p < 0.05), ADG in the growing phase (0–6 weeks; p < 0.05), and ADFI in the finishing phase with a tendency (7–12 weeks; p = 0.06) as the inclusion level of CM increased. However, the BW at 12 weeks (linear, p < 0.05 and quadratic, p = 0.06), the overall ADG (0–12 weeks; linear and quadratic, p < 0.05), and the G:F ratio in the finishing (7–12 weeks; linear, p < 0.05) and overall (0–12 weeks; linear, p < 0.05) phases decreased with increasing levels of CM in the diets. The ATTD of crude protein (linear, p < 0.05), crude fiber (linear, p < 0.05), and ash (linear, p < 0.05) decreased linearly as the inclusion level of CM increased. The BUN concentrations increased linearly with increasing levels of CM in the diets at 12 weeks of the experiment (p < 0.05). As the inclusion level of CM increased, TBARS value at d 3 post-mortem (linear, p = 0.07) tended to increase, whereas initial loin pH at 1 h post-mortem decreased (linear and quadratic, p < 0.05) with no difference in ultimate loin pH at 24 h post-mortem. These results indicated that CM inclusion up to 12% in the growing-finishing pig diets with β-mannanase did not affect growth performance, nutrient utilization, and pork quality whereas 18% CM inclusion to the diets could negatively impact nutrient digestibility, BUN concentrations, and thereby growth performance.

Standardized total tract digestibility of phosphorus in copra meal, palm kernel expellers, palm kernel meal, and soybean meal fed to growing pigs

Sixty-six barrows (initial BW: 27.4 ± 2.8 kg) were used to determine the standardized total tract digestibility (STTD) of P in copra meal (CM), palm kernel expellers from Indonesia (PKE-IN), palm kernel expellers from Costa Rica (PKE-CR), palm kernel meal from Costa Rica (PKM), and soybean meal (SBM) without or with exogenous phytase. Pigs were housed individually in metabolism cages and allotted to 11 diets with 6 replicate pigs per diet in a generalized randomized block design. Five diets were formulated by mixing cornstarch and sugar with CM, PKE-IN, PKE-CR, PKM, or SBM. Five additional diets, which were identical to the initial 5 diets but supplemented with 800 units of phytase, were also formulated. A P-free diet was used to measure basal endogenous losses of P by the pigs. Feces were collected for 5 d using the marker to marker approach after a 5-d adaptation period. Analyzed total P in CM, PKE-IN, PKE-CR, PKM, and SBM was 0.52, 0.51, 0.53, 0.54, and 0.67%, respectively. Phytate P was 0.22, 0.35, 0.38, 0.32, and 0.44% in CM, PKE-IN, PKE-CR, PKM, and SBM, respectively. Addition of phytase increased (P < 0.05) the apparent total tract digestibility (ATTD) of P from 60.6 to 80.8, 27.3 to 56.5, 32.6 to 59.9, 48.9 to 64.1, and 41.1 to 72.2% in CM, PKE-IN, PKE-CR, PKM, and SBM, respectively. The ATTD of P in CM was greater (P < 0.05) than in any of the other ingredients. The ATTD of P in SBM and PKM was greater (P < 0.05) than in PKE-IN, with PKE-CR being intermediate. The STTD of P increased (P < 0.05) from 70.6 to 90.3, 37.6 to 66.4, 43.2 to 69.9, 57.9 to 73.5, and 49.6 to 81.1% in CM, PKE-IN, PKE-CR, PKM, and SBM, respectively, when microbial phytase was added to the diets. When expressed as a percentage of total P, phytate P concentration in the ingredient negatively affected (P < 0.05) the ATTD of P (107.09 - 1.0564 × % phytate P; R(2) = 87.1) and the STTD of P (116.3 - 1.0487 × % phytate P; R(2) = 89.4). In conclusion, microbial phytase increased P digestibility of CM, PKM, PKE-CR, PKE-IN, and SBM when fed to growing pigs, and the concentration of phytate P affects the response to microbial phytase.