Effects of exogenous α-(1,4)-amylase on the utilisation of corn starch and glucose metabolism in broiler chickens

The effect of amylase, chromium propionate and their combination supplementation on growth performance, carcass traits, serum parameters, antioxidant capacity and intestinal health in yellow feathered broilers

To better understand the growth promotion mechanism of amylase and chromium propionate (Cr Prop) and assess their potential synergistic effects, a total of 640 one-day-old male yellow-feathered broilers were randomly allocated to four dietary treatments with eight replicates. The birds were fed either a basal diet or the basal diet supplemented with amylase, Cr Prop or a combination of both. The results showed that during the grower, finisher and overall phases, average daily feed intake, final body weight, and feed conversion ratio were significantly improved (P < 0.05) in the amylase and Cr Prop treatment groups. However, no significant differences (P > 0.05) were observed in carcass traits. Amylase supplementation alone significantly reduced breast muscle drip loss (P < 0.05). Amylase supplementation significantly increased (P < 0.05) the concentration of glutathione peroxidase in breast muscle and plasma, as well as catalase in breast muscle, while it decreased (P < 0.05) catalase in the liver and malondialdehyde in breast muscle. Supplementation with Cr Prop significantly elevated (P < 0.05) the concentration of glutathione peroxidase in the liver and plasma, as well as the concentration of total superoxide dismutase in the liver, while it reduced (P < 0.05). the concentration of malondialdehyde in breast muscle. Supplementation with either amylase or Cr Prop significantly increased (P < 0.05) the levels of blood high-density lipoprotein cholesterol, immunoglobulin A, immunoglobulin G, and total protein, while significantly reducing (P < 0.05) triglyceride levels. Amylase supplementation alone notably enhanced villus height in both the jejunum and ileum. Furthermore, amylase or Cr Prop significantly upregulated (P < 0.05) the mRNA expression of Occludin and Claudin-1 in the Jejunum. The expression of Zona Occluden-1 was elevated by Cr Prop. However, the expression of Mucin 2 and Zona Occluden-2 remained unaffected. While amylase or Cr Prop supplementation alone could improve the performance and several healthy parameters in yellow-feathered broilers, no synergistic effect was observed.

Different starch sources and amino acid levels on growth performance, starch and amino acids digestion, absorption and metabolism of 0- to 3-week-old broilers fed low protein diet

The synchronized absorption of amino acids and glucose in the gut is essential for amino acid utilization and protein synthesis in the body. The study aimed to investigate how the starch digestion rate and amino acid levels impact the growth and intestinal starch and amino acid digestion, transport, and metabolism in juvenile broilers. The experiment was conducted with 702 Arbor Acres Plus broilers at 1 d old, which were randomly divided into 9 treatments with 6 replicates of 13 chickens each. The treatments included 3 different starch sources (corn, waxy corn, and tapioca) with 3 different apparent ileal digestible lysine (AID Lys) levels (1.08%, 1.20%, and 1.32%). A notable interaction was noted for dietary starch sources and AID Lys levels in the feed-to-gain ratio (F/G) and distal ileal starch digestibility (P < 0.01). The tapioca starch and waxy corn starch diets with 1.32% of AID Lys significantly decreased F/G compared with corn starch (P < 0.01). There was no significant difference in F/G of broilers among waxy corn starch diet with 1.08% AID Lys level, tapioca starch diet with 1.20% AID Lys level, and corn starch diet with 1.32% AID Lys level (P > 0.05). The 1.32% AID Lys level and the waxy corn starch both improved the body weight (BW) of broilers from 0 to 3 weeks of age, intestinal starch digestibility, and intestinal villi height or the ratio of villi height to crypt depth (P < 0.05). Compared with the corn starch diet, waxy corn starch and tapioca starch diets significantly elevated the AID of Met, Glu, Lys, Arg, Asp, His, Ile, Tyr, Gly, and Val levels (P < 0.05). The carbon metabolomics results revealed that the waxy corn starch diet significantly reduced malic acid and cis-aconitic acid levels (P < 0.05) in the tricarboxylic acid cycle compared to the corn starch diet. It was concluded that a waxy corn starch diet improves the growth performance of broilers by improving intestinal morphology, increasing the absorption and transport of amino acids, reducing the amino acid oxidation for energy supply in the intestinal mucosa, and promoting protein synthesis in muscles, which not only reduces the need for dietary AID Lys but also saves on production costs.

Effects of tannic acid on growth performance, intestinal health, and tolerance in broiler chickens

This study investigated the optimal tannic acid dosage and assessed tolerance levels in broiler chickens. In experiment 1, 525 broilers were randomly divided into 5 treatment groups, the control group (CON group) and groups TA1 to TA4, corresponding to treatments of 0.025, 0.05, 0.075, and 0.1 % tannic acid, respectively, to determine the effect of tannic acid on broiler growth performance and gut health. Experiment 2 was performed to evaluate the tolerance of tannic acid; 416 broilers were randomly divided into control (CTR), 0.075 % tannic acid (TA), 0.375 % tannic acid (5TA), and 0.75 % tannic acid (10TA) groups. In the first experiment, compared with that in the CON group, the growth performance and the ileal intestinal villi height to crypt depth ratio showed a quadratic curve increase with tannic acid supplementation (P < 0.05). Adding 0.05 % to 0.075 % tannic acid significantly improved the growth performance, intestinal morphology, and intestinal barrier function (P < 0.05). Tannic acid concentrations of 0.075 % significantly increased the abundance of Firmicutes and Lactobacillaceae in the ileum and decreased the abundance of Vibrionaceae and Yersiniaceae (P < 0.05). In experiment 2, the growth performance of the TA group significantly improved compared with that of the CTR group (P < 0.05). The F/G was significantly higher in the 5TA and 10TA groups than in the CTR group (P < 0.05), and the 10TA group had significantly reduced body weight on d 21 (P < 0.05). The addition of tannic acid resulted in significant glomerular and glandular hyperplasia, as well as muscularis thickening of the gizzard mucosa. However, broilers could not tolerate tannic acid doses of 0.375 % and above. Tannic acid supplementation may protect the proventriculus mucosal layer, reduce villi atrophy, and enhance growth performance by positively influencing the intestinal microbiota, villus morphology, and intestinal barrier function.

Anti-Incretin Gut Features Induced by Feed Supplementation with Alpha-Amylase: Studies on EPI Pigs

The acini-islet-acinar (AIA) axis concept justifies the anatomical placement of the Langerhans islets within the exocrine pancreatic parenchyma and explains the existence of the pancreas as a single organ. Amylase has been suggested to play a key role as an anti-incretin factor. Oral glucose tolerance tests (OGTT) were performed on 18 piglets in both a healthy (prior to pancreatic duct ligation (PDL) surgery, study Day 10) and an exocrine pancreatic insufficient (EPI) state (30 days after PDL, study Day 48)). Amylase (4000 units/feeding) or Creon® (100,000 units/feeding) was administered to pigs with the morning and evening meals, according to study design randomization, for 37 days following the first OGTT. Blood glucose levels, as well as plasma levels of insulin, GLP-1, and GIP, were measured, and the HOMA-IR index was calculated. EPI status did not affect the area under the curve (AUC) of insulin release, fasting insulin levels, or the HOMA-IR index, while amylase supplementation led to a significant (p < 0.05) decrease in the above-mentioned parameters. At the same time, EPI led to a significant (p < 0.05) increase in GLP-1 levels, and neither amylase nor Creon® supplementation had any effects on this EPI-related increase. Fasting plasma levels of GIP were not affected by EPI; however, the GIP response in EPI and Amylase-treated EPI animals was significantly lower (p < 0.05) when compared to that of the intact, healthy pigs. Orally administered amylase induces gut anti-incretin action, normalizing glucose homeostasis and reducing HOMA-IR as a long-term outcome, thus lowering the risk of diabetes type II development. Amylase has long-lasting anti-incretin effects, and one could consider the existence of a long-lasting gut memory for amylase, which decreases hyperinsulinemia and hyperglycemia for up to 16 h after the last exposure of the gut to amylase.

Identification of Runs of Homozygosity Islands and Functional Variants in Wenchang Chicken

Wenchang chickens, a native breed in the Hainan province of China, are famous for their meat quality and adaptability to tropical conditions. For effective management and conservation, in the present study, we systematically investigated the characteristics of genetic variations and runs of homozygosity (ROH) along the genome using re-sequenced whole-genome sequencing data from 235 Wenchang chickens. A total of 16,511,769 single nucleotide polymorphisms (SNPs) and 53,506 ROH segments were identified in all individuals, and the ROH of Wenchang chicken were mainly composed of short segments (0-1 megabases (Mb)). On average, 5.664% of the genome was located in ROH segments across the Wenchang chicken samples. According to several parameters, the genetic diversity of the Wenchang chicken was relatively high. The average inbreeding coefficient of Wenchang chickens based on F_HOM, F_GRM, and F_ROH was 0.060 ± 0.014, 0.561 ± 0.020, and 0.0566 ± 0.01, respectively. A total of 19 ROH islands containing 393 genes were detected on 9 different autosomes. Some of these genes were putatively associated with growth performance (AMY1a), stress resistance (THEMIS2, PIK3C2B), meat traits (MBTPS1, DLK1, and EPS8L2), and fat deposition (LANCL2, PPARγ). These findings provide a better understanding of the degree of inbreeding in Wenchang chickens and the hereditary basis of the characteristics shaped under selection. These results are valuable for the future breeding, conservation, and utilization of Wenchang and other chicken breeds.

The Effect of Exogenous Amylase Supplementation on the Nutritional Value of Pea (Pisum sativum L.) for Broiler Chickens

The present study aimed to investigate whether the exogenous addition of amylase enhances the nutritional value of pea seeds for broiler chickens. In total, 84 1-day-old male broiler chickens (Ross 308) were used for the experimental study. During the first phase of the experiment (1-16 d), all birds in each treatment were fed with a corn-soybean meal reference diet. After this time, the first treatment (control) was still fed the reference diet. In the second and third treatment, 50% of the reference diet was replaced with 50% pea seeds. In addition, the third treatment was supplemented with exogenous amylase. Animal excreta were collected on 21 d and 22 d of the experiment. The birds were sacrificed at the end of the experiment (23 d), and samples of ileum content were collected. The experimental results showed that the exogenous addition of amylase significantly improved (p < 0.05) the apparent ileal digestibility (AID) of the crude protein (CP), starch, and dry matter (DM) of pea. In addition, an improvement in the AID of essential amino acids in pea seeds (except Phe) was observed. The trend in the AME_N values was also noted (p = 0.076). It can be concluded that supplementation with exogenous amylase improves the nutritional value of pea seeds in broiler chicken nutrition.

Dietary Bacillus licheniformis shapes the foregut microbiota, improving nutrient digestibility and intestinal health in broiler chickens

Bacillus licheniformis is considered a potential alternative to antibiotic growth promoters of animal growth and health. However, the effects of Bacillus licheniformis on the foregut and hindgut microbiota, and their relationships with nutrient digestion and health, in broiler chickens remain unclear. In this study, we aimed to identify the effects of Bacillus licheniformis BCG on intestinal digestion and absorption, tight junctions, inflammation, and the fore- and hind-gut microbiota. We randomly assigned 240 1-day-old male AA broilers into three treatment groups: CT (basal diet), BCG1 (basal diet + 1.0 × 10⁸ CFU/kg B. licheniformis BCG), and BCG2 (basal diet + 1.0 × 10⁹ CFU/kg B. licheniformis BCG). On day 42, the jejunal and ileal chyme and mucosa were subjected to analysis of digestive enzyme activity, nutrient transporters, tight junctions, and signaling molecules associated with inflammation. The ileal and cecal chyme were subjected to microbiota analysis. Compared with the CT group, the B. licheniformis BCG group showed significantly greater jejunal and ileal α-amylase, maltase, and sucrase activity; moreover, the α-amylase activity in the BCG2 group was higher than that in the BCG1 group (P < 0.05). The transcript abundance of FABP-1 and FATP-1 in the BCG2 group was significantly greater than that in the CT and BCG1 groups, and the GLUT-2 and LAT-1 relative mRNA levels were greater in the BCG2 group than the CT group (P < 0.05). Dietary B. licheniformis BCG resulted in significantly higher ileal occludin, and lower IL-8 and TLR-4 mRNA levels than observed in the CT group (P < 0.05). B. licheniformis BCG supplementation significantly decreased bacterial community richness and diversity in the ileum (P < 0.05). Dietary B. licheniformis BCG shaped the ileac microbiota by increasing the prevalence of f_Sphingomonadaceae, Sphingomonas, and Limosilactobacillus, and contributed to nutrient digestion and absorption; moreover, it enhanced the intestinal barrier by increasing the prevalence of f_Lactobacillaceae, Lactobacillus, and Limosilactobacillus. Dietary B. licheniformis BCG decreased microbial community diversity by diminishing Desulfovibrio, Alistipes, Campylobacter, Vibrio, Streptococcus, and Escherichia coli-Shigella levels, and down-regulating inflammatory associated molecule expression. Therefore, dietary B. licheniformis BCG contributed to digestion and absorption of nutrients, enhanced the intestinal physical barrier, and decreased intestinal inflammation in broilers by decreasing microbial diversity and optimizing the microbiota structure.

Supplemental Enzyme and Probiotics on the Growth Performance and Nutrient Digestibility of Broilers Fed with a Newly Harvested Corn Diet

A new grain phenomenon happens in newly harvested corn because of its high content of anti-nutritional factors (ANFs), which can cause low nutrient digestibility and diarrhea in animals. Enzymes and probiotics have been shown to relieve the negative effect of ANFs for animals. The purpose of this study was to investigate the effect of enzymes and probiotics on the performance and nutrient digestibility of broilers, fed with newly harvested corn diets. A total of 624 Arbor Acres Plus male broiler chickens were randomly divided into eight treatment groups (A: normal corn diet, CT: newly harvested corn diet, DE: newly harvested corn diet + glucoamylase, PT: newly harvested corn diet + protease, XL: newly harvested corn diet + xylanase, BCC: newly harvested corn diet + Pediococcus acidilactici BCC-1, DE + PT: newly harvested corn diet + glucoamylase + protease, XL + BCC: newly harvested corn diet + xylanase + Pediococcus acidilactici BCC-1). Each group was divided into six replicates, with 13 birds each. On day 21, growth performance, nutrient digestibility, and digestive enzyme activity were measured. Compared with the normal corn diet (PC), the newly harvested corn diet (NC) produced shorter digesta emptying time (p = 0.015) and increased visual fecal water content (p = 0.002) of broilers, however, there was no effect on performance. Compared to the newly harvested corn diet (NC), supplemental enzyme of DE increased the activity of chymotrypsin (p = 0.016), however, no differences in the digestibility of three kinds of organic matter, digesta emptying time, visual fecal water content, or performance were found. Supplemental protease (PT) significantly increased digesta emptying time (p = 0.004) and decreased the activity of maltase (p = 0.007). However, it had no effect on the digestibility of three kinds of organic matter or the performance of broilers. Supplemental xylanase (XL) decreased the activity of amylase (p = 0.006) and maltase (p < 0.001); however, it had no effect on digesta emptying time, visual fecal water content, the digestibility of three kinds of organic matter, or performance of broilers. Supplemental DE, combined with PT (DE + PT), increased the digesta emptying time (p = 0.016) while decreasing the visual fecal water content (p = 0.011), and the activity of amylase (p = 0.011), lipase (p = 0.021), and maltase (p < 0.001), however, there was no effect on performance. Supplemental BCC individually decreased the activity of amylase (p = 0.024) and maltase (p < 0.001), however, it increased the activity of trypsin (p < 0.001) and tended to improve feed conversion ratio (FCR) (p = 0.081). Supplemental BCC-1, combined with XL (XL + BCC), increased the activity of trypsin (p = 0.001) but decreased the activity of amylase (p = 0.013), lipase (p = 0.019), and maltase (p < 0.001). Pediococcus acidilactici BCC-1 (109 cfu/kg), protease (800,000 U/g) individually, or protease (800,000 U/g) in combination with glucoamylase (800,000 U/g) were supplemented in newly harvested corn diets for growing broilers. Hence, this study mainly explores the alleviation effect of enzyme and probiotics on the negative phenomenon caused by the utilization of newly harvested corn in broilers and provides a better solution for the utilization of newly harvested corn in production practice.