Effect of Pre-Treating Dietary Green Seaweed with Proteolytic and Fibrolytic Enzymes on Physiological and Meat Quality Parameters of Broiler Chickens

The use of seaweeds as nutraceuticals in chicken diets is limited by high fibre levels and low protein digestibility. Therefore, we tested the effect of pre-treating dietary seaweed (Ulva sp.) with a combination of protease and fibrolytic enzymes on physiological and meat quality parameters of Cobb 500 broilers. Five dietary treatments were formulated by including untreated (T1); fibrolytic (12 g/kg) enzyme-treated (T2); fibrolytic (12 g/kg) and protease (5 g/kg) enzyme-treated (T3); fibrolytic (12 g/kg) and protease (10 g/kg) enzyme-treated (T4); fibrolytic (12 g/kg) and protease (15 g/kg) enzyme-treated (T5) seaweed (35 g/kg) in a standard broiler diet. Three hundred, two-week-old chicks (239.3 ± 8.57 g live weight) were evenly distributed to 30 replicate pens to which the diets were then randomly allocated. Birds fed diet T1 had the highest feed intake (1144.5 g/bird). Neither linear nor quadratic trends were recorded for growth performance and carcass traits in response to protease pre-treatment levels. Gizzard weight linearly increased, while symmetric dimethylarginine, calcium, meat pH24, and hue angle24 quadratically responded to protease levels. Diet T1 promoted the lowest serum phosphorus levels (3.37 mmol/L). In conclusion, pre-treatment of seaweed with a combination of protease and fibrolytic enzymes did not improve diet utilization, physiological parameters, and meat quality in broilers.

Effects of microbial inoculant and fibrolytic enzymes on fermentation quality and nutritional value of BRS capiaçu grass silage

The objective of this study was to evaluate the effect of bacterial-enzymatic inoculants with different concentrations of fibrolytic enzymes on the fermentation quality and nutritional value of the silage of BRS capiaçu grass. Two bacterial-enzymatic inoculants with different levels of enzyme complex were evaluated (Silotrato® (5%) and Biotrato® (8%)) and control silage (without additive) according to a completely randomized design with eight replicates. To evaluate the silage aerobic stability, a completely randomized split plot design was used with three treatments (plots) and seven times after opening (subplots). There was no interaction between treatments and times after opening on values of pH (P=0.79). Regarding bacterial-enzymatic inoculants, the silage pH was 21.66% and 16.16% higher in silage without additive (mean of 6.00) compared to silage with 5% and 8% enzyme complex (P < 0.01). There was no difference between treatments on pH (P = 0.08), lactic acid (p = 0.08) and acetic acid (p = 0.64), means of 3.11, 47.31 g dry matter (DM)-1 and 11.19 g DM-1, respectively. There was no difference between treatments for any of the chemical composition variables (P = 0.86). Mean values for DM, crude protein, neutral detergent fiber and total digestible nutrients were 22.31%, 6.65%, 71.15% and 42.07%, respectively. There was a higher concentration of butyric acid in the control silage compared to Silotrato® silage. The control silage and silage treated with Biotrato® presented effluent losses (P = 0.05) 13.99% higher than silage with Silotrato®. For ensiling BRS capiaçu grass, it is recommended to use lactic acid bacteria containing 5% fibrolytic enzymes.

Effects of addition of exogenous fibrolytic enzymes on digestibility and milk and meat production – a systematic review

Exogenous fibrolytic enzymes (EFE) added to the ruminant diet can increase fiber digestibility and production efficiency. A systematic review was conducted to understand the interactions between EFE and diet on digestibility and animal performance. The database included variables from 384 experiments with EFE and 264 controls from 85 papers published since 2000 (classification criteria: 1) type of study (in vitro, in situ, in vivo), 2) type of ruminants (sheep, Buffaloes, goats, beef and dairy cattle), 3) primary EFE activity (Cellulases (Cel) or Xylanases (Xyl)), 4) forage proportion (FP), 5) type of plant (TP: legumes or grasses), 6) number of ingredients in diets, and 7) application time (AT)). In over of 52.85% of cases, EFE improved the degradability of dry matter (DMD), neutral and acid detergent fiber (NDFD and ADFD), in vitro gas production (GP), volatile fatty acids (VFA), the acetate: propionate ratio (A:P ratio), protein and fat milk, milk yield and average daily gain (ADG) (by 7.78–21.85%). Cel improved organic matter degradability (OMD), GP, VFA, milk yield, and milk protein and fat content. EFE in FP≥40% diets enhanced the ADG, and in grass-based diets increased the dry matter intake (DMI). The AT of EFE affected the DMD, NDFD, and ADFD. Significant correlations were found between the improvements of NDFD or ADFD with DMD (r>0.59), milk yield (r=0.64), and ADG (r=0.59). In conclusion, many factors interact with EFE supplementation effects, but EFE consistently enhanced the DMD, NDFD, and ADFD of ruminant diets, which are related to improvements in productive performance.