Effect of Supplemental Protease on Growth Performance and Excreta Microbiome of Broiler Chicks

Effect of a novel alkaline protease from Bacillus licheniformis on growth performance, carcass characteristics, meat quality, antioxidant capacity, and intestinal morphology of white feather broilers

BACKGROUND

The present study was conducted to investigate the effects of dietary novel alkaline protease from Bacillus licheniformis on the growth performance, meat quality, antioxidant status and intestinal morphology of broilers. In total, 4000 broilers were randomly assigned into five groups and treated with normal control, normal control + 100 mg kg-1 protease, normal control + 200 mg kg-1 protease, normal control + 300 mg kg-1 protease and normal control + 400 mg kg-1 protease.

RESULTS

Supplementing protease impacted final body weight (linear, P = 0.003; quadratic, P = 0.006) and decreased feed conversion rate (linear, P = 0.036) in broilers. Moreover, dietary protease significantly increased breast muscle rate (linear, P = 0.005; quadratic, P = 0.021) and decreased drip loss (linear, P < 0.001; quadratic, P < 0.001). In addition, dietary protease notably increased protein digestibility (linear, P = 0.001; quadratic, P = 0.006) and trypsin activity (linear, P = 0.002; quadratic, P = 0.009) in jejunum. Light microscopy revealed that the jejunum villi in the 300 mg kg-1 and 400 mg kg-1 groups exhibited greater height and a denser arrangement compared to those in the control group. The addition of protease decreased malondialdehyde content (linear, P < 0.001; quadratic, P < 0.001) and increased total antioxidant capacity (linear, P = 0.001; quadratic, P < 0.001) in pectoral muscles.

CONCLUSION

The results of the present study suggest that dietary novel alkaline protease from B. licheniformis improved growth performance by affecting trypsin activity, protein digestibility, antioxidant capacity and intestinal health. © 2024 Society of Chemical Industry.

Dietary novel alkaline protease from Bacillus licheniformis improves broiler meat nutritional value and modulates intestinal microbiota and metabolites

BACKGROUND

Different types of exogenous protease supplements have a positive impact on animal performance, but their effects on the nutritional value of meat and the gut microbial community of broilers have not been extensively studied. The objective of this investigation was to determine the impact of supplementation with a novel alkaline protease derived from Bacillus licheniformis (at doses of 0, 100, 200, 300, and 400 g/t) on the fatty acid and amino acid profiles, inosine monophosphate (IMP) levels, total volatile basic nitrogen (TVB-N) content found within the breast muscle, as well as the impact on the cecal microbiota and metabolites.

RESULTS

Supplementation with 200-400 g/t of the novel protease resulted in a significant elevation in the concentration of essential amino acids (P < 0.001), flavor amino acids (P < 0.001), and total protein (P = 0.013) within the breast muscle. Results derived from the 16S rRNA sequencing and untargeted metabolomics analysis of the cecal content revealed that the novel protease reshaped the cecal microbial and metabolite profiles. In particular, it led to increased relative abundances of Bacteroides, Lactobacillus, Alistipes, and Eubacterium, while simultaneously causing a reduction in the metabolites of D-lactic acid and malonic acid. Moreover, correlation analyses unveiled significant relationships between distinct microbes and metabolites with the contents of IMP, fatty acids, and amino acids in the broiler's breast muscle.

CONCLUSION

In summary, the novel protease regulated the intestinal microbial community and metabolism, thereby inducing changes in the compositions of fatty acids and amino acids profiles, as well as IMP levels in broiler meat. These alterations significantly contributed to the enhancement of the nutritional value and flavor of the meat.

Effects of crude protease produced by Bacillus subtilis (MAFIC Y7) on growth performance, immune indices, and anti-inflammatory responses of broilers fed soybean meal- or cottonseed meal-based diets

A strain of Bacillus subtilis (MAFIC Y7) was isolated from the intestine of Tibetan pigs and was able to express high protease activity. The aim of this study was to characterize the proteases produced by MAFIC Y7, and to investigate the effects of protease addition on growth performance, ileal amino acid digestibility, and serum immunoglobulin and immune factors of broilers fed SBM-based diets, or on growth performance, carcass characteristics, and intestinal morphology of broilers fed CSM-based diets. B. subtilis (MAFIC Y7) expressed protease showed its optimal enzyme activity at 50 °C and pH 7.0. The coated crude enzyme (CCE) showed greater stability at pH 3.0 than its uncoated counterpart. Experiment 1 was conducted with six diets based on three levels of crude protein (CP)-CPlow, CPmedium, and CPhigh-with or without CCE. In CPlow, CCE increased gain:feed (G:F) (days 1 to 21, days 1 to 42) by 8%, 3%, respectively, and enhanced apparent ileal digestibility (AID) of crude protein and lysine (on day 42) by 8.8%, 4.6%, respectively, compared with diets containing no CCE (P < 0.05). CCE increased G:F from days 1 to 21 from 0.63 to 0.68, improved G:F and average daily gain (ADG) during days 1 to 42, and enhanced AID of crude protein, lysine, cysteine, and isoleucine on day 42 compared with the unsupplemented treatments (in CPmedium, P < 0.05). CCE increased serum IgA (on day 21), serum IgA and IgG and increased serum IL-10 (on day 42), but decreased serum tumor necrosis factor-α (TNF-α; on day 21), and serum IL-8 and TNF-α (on day 42) compared with unsupplemented treatments. At CPhigh, CCE decreased serum levels of IL-6 and TNF-α (on day 21), and IL-8 and TNF-α (on day 42) compared with unsupplemented treatments (in CPhigh, P < 0.05). In experiment 2, CSM-based diets with two lysine-to-protein ratios (5.2% or 5.5%) with or without CCE. In the high Lys diet (5.5% Lys:protein), CCE increased ADG and G:F, increased carcass, but decreased abdominal fat compared with the unsupplemented treatment (P < 0.05). In the 5.2% Lys:protein dietary treatment, CCE improved duodenal villus height compared with the unsupplemented treatment (P < 0.05). Supplementation of protease produced by MAFIC Y7 was associated with lower inflammatory responses in SBM diets (CPmedium or CPhigh) and improved ADG in broilers fed CPmedium or CPhigh. The proteases improved ADG and the efficiency of CSM use when the ratio of Lys to protein was 5.5%.

Growth performance of broiler chickens fed diets supplemented with amylase and protease enzymes individually or combined

Background

Feed additives that increase nutrient availability in feeds have gained a lot of interest.

Aim

An experiment was conducted to determine whether amylase, protease, and their combined supplementation affected broiler performance.

Methods

Two hundred eighty broiler chicks were selected and distributed randomly into 28 replicate pens with four treatment groups and seven replicates under a completely randomized design. A total of four diets were developed, having 0, 100, 100, and 100 + 100 g of control (AP0), amylase (A1), protease (P1), and amylase + protease (AP1)/ton of feed, respectively. Four replicates of each treatment were fed each diet. Each diet was randomly allotted to each group. Ad-libitum feeding was provided to the birds. The feeding program had starter and finisher diets. Upon completion of the experiment, three birds from each pen were slaughtered to analyze the carcass characteristics and organ weight.

Results

Differences were insignificant between 100 g/ton of amylase supplementation and FI, body weight gain (BWG), or feed conversion ratio (FCR) (p > 0.05). Supplementation with 10 0g/ton of protease did not significantly affect FI, BWG, and FCR (p > 0.05). Similarly, 100 + 100 g/ton of amylase + protease addition had no significant effect on FI, BWG, and FCR (p > 0.05). None of the treatments significantly affected carcass weight, abdominal fat percentage, dressing percentage, drumstick, wings, breast, and thigh weights (p > 0.05). In addition, there were no significant effects (p > 0.05) on the weight of the heart, liver, gizzard, and spleen.

Conclusion

In conclusion, amylase, protease, and their combined supplementation at a rate of 100 g/ton of feed did not influence BWG, FI, FCR, carcass characteristics, or organ weight.

Effects of Different Doses of Multienzyme Supplementation on Growth Performance, Duodenal pH and Morphology, and Carcass Traits in Broilers Fed Diets with an Increasing Reduction in Energy

This study evaluated the effects of supplementing different doses of a multienzyme (KZP) consisting of carbohydrases and a protease on growth performance, duodenal pH and morphology, and carcass traits in broilers fed diets with increasing reductions in energy. One thousand two hundred one-day-old broiler chicks were allocated to five dietary treatments with eight replicates of 30 birds each: a positive control diet formulated to meet Arbor Acres' nutritional requirements (PC); a negative control diet reformulated to 80 kcal/kg less than the apparent metabolizable energy (AME) of the PC (NC1); a negative control diet reformulated to 120 kcal/kg less than the AME of the PC (NC2); an NC1 diet supplemented with 300 g/t of KZP (NC1 + KZP300); and an NC2 supplemented with 500 g/t of KZP (NC2 + KZP500). Growth performance was measured throughout the study. At 35 days, 10 birds per treatment were randomly selected and euthanized for a carcass trait evaluation, and samples of the duodenum were collected for morphological examination and pH level determination. The final average body weight and feed conversion ratio were better (p < 0.05) for the broilers in the NC1 + KZP300 group compared to those in NC1, NC2 and NC2 + KZP500 groups and were similar to those of the PC birds (p > 0.05). Birds from the NC1 + KZP500 group showed a better (p < 0.05) final body weight and feed efficiency compared to the NC1 and NC2 groups. The villus height was greater (p < 0.05) for the PC and NC1 + KZP300 groups compared to the rest of the treatments. The crypt depth was longer (p < 0.05) for the NC1 and NC2 groups compared to the NC1 + KZP300 group. The supplementation of KZP to both the NC1 and NC2 diets reduced (p < 0.05) the abdominal fat %. This study demonstrates that supplementing energy-reduced diets with KZP improved performance in broiler chickens.

Supplemental enzymes and probiotics on the gut health of broilers fed with a newly harvested corn diet

Gut health is important for digestion and absorption of nutrient for animals. The purpose of this study was to investigate the therapeutic effect of enzymes and probiotics alone or in combination on the gut health of broilers fed with newly harvested corn diets. A total of 624 Arbor Acres Plus male broiler chickens were randomly divided into 8 treatment groups (PC: normal corn diet, NC: newly harvested corn diet, DE: NC + glucoamylase, PT: NC + protease, XL: NC + xylanase, BCC: NC + Pediococcus acidilactici BCC-1, DE + PT: NC + glucoamylase + protease, XL+BCC: NC + xylanase + Pediococcus acidilactici BCC-1). Each group was divided into 6 replicates, with 13 birds each. On d 21, intestinal morphological, intestinal tight junction and aquaporins gene expression, cecal short-chain fatty acid concentrations, and microflora were measured. Compared with the newly harvested corn diets (NC), supplemental glucoamylase (DE) significantly increased the relative abundance of Lachnospiraceae (P < 0.05) and decreased the relative abundance of Moraxellaceae (P < 0.05). Supplemental protease (PT) significantly increased the relative abundance of Barnesiella (P < 0.05), but the relative abundance of Campylobacter decreased by 44.4%. Supplemental xylanase (XL) significantly increased the jejunal mRNA expressions of MUC2, Claudin-1, and Occludin (P < 0.01), as well as the cecal digesta contents of acetic acid, butyric acid, and valeric acid (P < 0.01). Supplemental DE combined with PT increased the ileal mRNA expressions of aquaporins (AQP) 2, AQP5, and AQP7 (P < 0.01). Supplemental BCC significantly increased the jejunal villus height and crypt depth (P < 0.01), the jejunal mRNA expressions of MUC2, Claudin-1 and Occludin (P < 0.01), and the relative abundance of Bacteroides (P < 0.05). Supplemental xylanase in combination with BCC significantly increased jejunal villus height and crypt depth (P < 0.01), the ileal mRNA expressions of AQP2, AQP5 and AQP7 (P < 0.01), and the cecal digesta contents of acetic acid, butyric acid, and valeric acid (P < 0.01). This suggests that inclusions of supplemental protease (12,000 U/kg), glucoamylase (60,000 U/kg), or Pediococcus acidilactici BCC-1 (10⁹ cfu/kg) individually or in combination with xylanase (4,800 U/kg) in the newly harvested corn diets can alleviate diarrhea in broilers, and be beneficial for the gut health.

Drug-independent control strategy of clostridial infection in broiler chickens using anti-toxin environmentally friendly multienzymes

The study investigated the effect of enzymes as a toxin detoxifier (DETOXIZYME) dietary supplementation on performance during growth, blood chemistry, and immunity under clostridia infection in chickens. A total of 480, day-old male chicks were randomly distributed to four groups, with six replicates of 20 birds each. The first control negative treatment (A) fed the basal formula as commercial feed prepared following the strain's needs, the second control positive group (B) fed the basal formula challenged with Clostridium perfringens (C. perfringens) type A, the third group (C) fed the basal formula with 100 g DETOXIZYME/ton of feed and challenged with clostridia, and the fourth group (D) fed the control basal formula with 100 g DETOXIZYME/ton of feed. DETOXIZYME dietary supplementation significantly boosted body weight (BW), body weight gain (BWG), feed intake (FI), and European production efficiency factor (EPEF) and improved the feed conversion rate (FCR) of the broilers. The dietary supplementation of DETOXIZYME significantly increased carcass trait and spleen. However, liver and abdominal fat weight significantly decreased compared with clostridia-challenged groups. The values of alanine aminotransferase (ALT), aspartate aminotransferase (AST), uric acid, creatinine, and Malondialdehyde (MDA) were decreased. While calcium, phosphate, zinc, and glutathione peroxidase (GPx) levels were improved in birds that took basal formulas fortified with DETOXIZYME contrary to the other treatment groups during 35 days of age. Plasma total cholesterol, triglyceride, and low-density lipoprotein (LDL) values were reduced versus the other treatment groups. Dietary supplementation of DETOXIZYME increased total protein, albumin, globulin, and Newcastle Disease (ND) immunity titer levels in the overall period compared to other groups. Dietary DETOXIZYME supplementation decreased clostridia and E. coli bacteria counts and improved gut morphometry. In conclusion, dietary supplementation of DETOXIZYME had a positive impact on performance, blood biochemistry, immunity, and bacterial counts and improved the gut morphology in broilers under clostridia infection.

Effects of a monocomponent protease from Bacillus licheniformis on broiler performance, digestibility, and carcass yield

Two experiments were carried out to evaluate the effects of protease addition to the diet of broilers at a higher level (1× or 2×) than the nutritional value proposed for the enzyme. The first experiment, 1280 day-old chicks (Cobb500®) were randomly allocated (randomized block design, 2×2+1 factorial arrangement), five treatments, eight replicates containing 32 birds/replicate. Treatments consisted: control diet without protease (CD); CD + 1× nutritional value of the enzyme (CDM1); CD + 2× nutritional value of the enzyme (CDM2); CDM1 + protease; and CDM2 + protease. The experimental period was 42 days. The mean weight (AFW), feed intake (FI), weight gain (WG), feed conversion, and carcass yield were evaluated. Significant differences were observed for AFW, WG, FI, abdominal fat yield, and feet percentage in the carcass. In the second experiment, 120 Cobb500® chicks at 14 days of age were allotted in a completely randomized design, 2×2+1 factorial arrangement, five treatments, six replicates with four birds/replicate. The treatments were consistent with the first experiment. Significant improvements in the nitrogen balance were observed for the broilers that received protease. The use of the enzyme tested is recommended with the recommended nutritional matrix, improving the zootechnical indices of broilers.

Community scale in-situ rapid biological reduction and resource recovery of food waste

In this study, a community-scale in-situ rapid biological reduction (IRBR) system was applied to achieve the rapid disposal and resource recovery of food waste (FW). A total of 5263 kg FW was processed in the 35 days of stably operation, during which 84.37% total mass reduction and 43.30% volatile solid removal were achieved, and the odor had been effectively controlled. Microbial sequencing results showed that aerobic and facultative thermophilic bacteria were major bacterial community, and vigorous metabolism of both carbohydrate and amino acid were maintained during the IRBR process. The final products have the potential to be recycled as organic fertilizers or bio-solid fuel to realize resource recovery. The results of economic analysis showed that the IRBR system had lower FW disposal costs due to the high automation. These results suggested that the IRBR system was an environmentally friendly, economical and practical method for the FW rapid treatment.

Effects of different feeding regimens with protease supplementation on growth, amino acid digestibility, economic efficiency, blood biochemical parameters, and intestinal histology in broiler chickens

Background

This study was conducted to estimate the impacts of using varied feeding regimens with or without protease supplementation on the growth performance, apparent amino acid ileal digestibility (AID%), economic efficiency, intestinal histology, and blood biochemical parameters of broiler chickens. Three hundred one-day-old chicks (Ross 308 broiler) were randomly allotted to a 3 × 2 factorial design. The experimental design consisted of three feeding regimens; FR1: a recommended protein SBM diet, FR2: a low-protein SBM diet, and FR3: a low-protein diet with the inclusion of 5% DDGS and 5% SFM, with or without protease supplementation (250 mg/kg).

Results

Increased feed intake and feed conversion ratio were observed in the FR3 treatment during the starter stage and decreased body weight and body weight gain during the grower stage. However, there was no significant effect of the different feeding regimens, protease supplementation, or interaction on the overall performance. The economic value of diets also remained unaffected by the different feeding regimens, protease supplementation, or interaction. Protease supplementation resulted in lowering the AID% of tryptophan and leucine. Reduced AID% of methionine was evident in the FR2 + VE and FR3 − VE treatments. Histological findings substantiated the FR3 treatment mediated a decrease in the duodenal and jejunal villous height (VH), jejunal villous width (VW), and ileal VW, whereas, increase in the ileal crypt depth (CD). The FR2 + VE treatment reduced the VH:CD ratio in the duodenum. The duodenal CD and the jejunal goblet cell count were reduced as a consequence of protease supplementation. The FR3 + VE treatment documented a rise in duodenal CD, while an increase in the jejunal goblet cell count was observed in the FR3 − VE treatment. The FR3 treatment enhanced the IgM serum levels compared to the FR1 and FR2 treatments. IgM serum levels were also elevated following protease supplementation. FR3 + VE treatment increased IgM serum levels. The highest serum ALP was found in the FR3 treatment, whereas the lowest level was obtained in the FR2 treatment.

Conclusion

Low-protein SBM-based diets could be used without affecting the birds’ growth. Altered morphometric measures of the intestine and increased IgM and ALP levels indicated the low-protein SBM/DDGS-SFM diet-induced damage of the intestinal histoarchitecture and immune system of birds. These different diets and protease supplementation failed to affect economic efficiency positively.

Probiotics and potential applications for alternative poultry production systems

Concerns over animal welfare continue to be a critical component of law and policies associated with commercial food animal production. Social and market pressures are the driving forces behind the legislation and result in the change of poultry production management systems. As a result, the movement toward cage-free and aviary-based egg production systems has become standard practices. Cage-based systems being replaced by alternative methods that offer a suitable housing environment to meet or exceed poultry welfare needs and require different management, including the ban of antibiotics in poultry diets. For broiler production, pasture- raised and free-range management systems have become more popular. However, challenges remain from exposure to disease-causing organisms and foodborne pathogens in these environments. Consequently, probiotics can be supplemented in poultry diets as commercial feed additives. The present review discusses the impacts of these probiotics on the performance of alternative poultry production systems for improving food safety and poultry health by mitigating pathogenic organisms and improving egg and meat quality and production.

Multienzyme Super-Dosing in Broiler Chicken Diets: The Implications for Gut Morphology, Microbial Profile, Nutrient Digestibility, and Bone Mineralization

Simple Summary

Optimizing the gut microbial community and morphometrical traits has become an increasingly prominent area of research due to recent evidence that suggests gut health and functionality affects the production performance of broilers. Creating a diverse microbial population can increase the nutrient digestibility of feed, as the microbes can break down a large portion of macromolecules and convert them into bioavailable substrates to be utilized by the host. A diverse microbiome can be promoted by a variety of additives, including feed enzymes. This study investigated the impact of the application of super-dosing multienzymes on gut morphology, microbial profile, nutrient digestibility, and bone mineralization in broiler chickens. Results found that super-dosing multienzymes improved nutrient digestibility, maintained a diverse microbial population, and tended to increase the overall villi morphology. Bone mineralization was not affected by increasing multienzyme doses. Additionally, the present study found three bacteria that were unique to multienzyme inclusion at a super-dose level.

Abstract

Optimizing gut health has a large impact on nutrient digestibility and bioavailability, and super-dosing feed enzymes may be one solution to achieve this. A 42-day grow-out trial was conducted using 192 Ross 308 broilers to determine if super-dosing Natuzyme at 0 g/t, 350 g/t, 700 g/t, and 1000 g/t dose rates could improve the gut morphology, alter the cecal microbial profile, enhance bone mineralization, and improve nutrient digestibility of a wheat–corn–soybean diet (six replicates per treatment, eight birds per pen). One bird per pen was slaughtered at day 42 and gut morphology, cecal microbial profile, and nutrient digestibility were studied. The addition of enzymes tended to increase the villus height in the duodenum, villus height, width, and crypt depth in the jejunum, and villus width and the number of goblet cells in the ileum. Microbial profiling revealed diverse communities; however, they did not significantly differ between treatment groups. Yet, 700 g/t Natuzyme promoted microbes belonging to the genus Romboutsia and Ruminococcus gauvreauii, while 1000 g/t Natuzyme promoted Barnesiella species. The nutrient digestibility demonstrated a significant improvement in all enzyme doses compared to the control. In conclusion, based on the outcomes of this study, a dose rate of 700 g/t Natuzyme is recommended to improve gut morphology and nutrient digestibility, and promote unique microbes which aid in feed efficiency.