Comparative effects of enzymatic soybean, fish meal and milk powder in diets on growth performance, immunological parameters, SCFAs production and gut microbiome of weaned piglets

Soybean protein isolate versus sheep whey protein: A detailed comparison of their chemical composition, gastrointestinal digestion and fermentation properties

Plant proteins are emerging as alternatives to animal proteins. This study compared the physicochemical properties and nutritional characteristics of soybean protein isolate (SPI) and sheep whey protein (SWP), which is gaining recognition for its nutritional benefits. SWP exhibited higher amino acid content, larger particle size, increased turbidity, and superior foaming and emulsification capacities compared to SPI (p < 0.05). In contrast, SPI demonstrated better emulsification stability. In vitro, gastrointestinal digestion showed that SPI achieved a higher degree of hydrolysis in both gastric and intestinal phases, although SWP had a faster initial hydrolysis rate. During gut microbiota fermentation, SWP produced significantly higher levels of short-chain fatty acids (SCFAs) than SPI (p < 0.05). Non-targeted metabolomics revealed distinct metabolic differences, particularly in amino acid metabolism, bile acid synthesis, and hormone biosynthesis. These findings suggest SWP is suitable for nutritional supplementation, while SPI is better for dairy-based alternatives.

Impact of replacing sow milk with milk replacer on growth performance, intestinal development, bacterial profile and muscular maturation in neonatal and nursery piglets

Along with the increasing litter sizes in pig industry, using milk replacer (MR) as a nutrient supplement has been widely practiced, yet the effects of replacing sow milk (SM) with MR on growth and development of piglets remain unclear. This study evaluated the differential effects of MR versus SM on growth performance, body composition, muscle fiber types, and intestinal health of piglets during the neonatal and nursery periods. Forty 2-day-old piglets, selected from 10 healthy sows, were randomly divided into two groups receiving either SM or MR ad libitum until postnatal day 23 (PND 23), then transitioned to be fed with nursery diet until PND 37. Blood, muscle, and intestinal tissues, along with colonic digesta and carcass samples, were collected on PND 12 (n = 10) and PND 37 (n = 10) for analysis of parameters related to intestinal function, microbiota composition and muscular development. The results showed that MR-fed piglets had lower average daily gain (ADG) and higher diarrhea index during the neonatal period. During the nursery period, however, MR-fed piglets had significantly higher average daily feed intake (ADFI) and ADG. Compared to SM-fed piglets, MR-fed piglets had a lower percentage of fast twitch fibers, but a higher percentage of slow twitch fibers on PND 12, along with lower body fat content on both PND 12 and PND 37. In addition, MR-fed piglets had significantly deeper crypt depth, increased mRNA expressions of inflammatory genes, and lower alpha diversity on PND 12. On PND 37, however, MR-fed piglets had higher villus height, increased sucrase activity and alpha diversity. On PND 12, likewise, MR-fed piglets were enriched with Prevotella associated with diarrhea, while SM-fed piglets were enriched with Lachnospiraceae associated with body fat deposition. In contrast, on PND 37, MR-fed piglets were enriched with commonly recognized beneficial bacteria, such as f_Muribaculaceae, g_Prevotellaceae_NK3B31_group, f_Oscillospiraceae and f_Rikenellaceae. These findings indicate that piglets fed MR experienced temporary growth check and intestinal complications in neonatal period, but intriguingly MR piglets had higher feed intake, compensatory growth, and recovery of intestinal function during the nursery period.

Soybean Bioactive Peptide Supplementation Affects the Intestinal Immune Antioxidant Function, Microbial Diversity, and Reproductive Organ Development in Roosters

Soybean is an important source of high-quality vegetable protein with various health-improving properties, and its main bioactive substances are small peptides produced by in vitro enzymatic hydrolytic processes. In traditional layer breeding, the nutritional health of roosters is frequently neglected, ultimately affecting the quality and quantity of offspring. This study investigated the effects of various quantities (0%, 0.15%, 0.30%, 0.45%, and 0.60%) of soybean bioactive peptide (SBP) feed additives on immunological and antioxidant functions, gut health, and reproductive performance of roosters. SBP supplementation significantly improved male growth and reproductive performance, including growth rate, feed conversion ratio, reproductive organ development, and semen quality. SBP also increased immune and antioxidant levels, boosted the integrity of the small intestinal physiological structure and barrier function, and diversity of cecal microbes, and decreased the apoptotic ratio of small intestinal epithelial cells. The effects of SBP on various functions of males showed a quadratic trend, with the optimal concentration determined to be 0.45%.

Utilization of Ningxiang pig milk oligosaccharides by Akkermansia muciniphila in vitro fermentation: enhancing neonatal piglet survival

Akkermansia muciniphila (A. muciniphila), an intestinal symbiont residing in the mucosal layer, shows promise as a probiotic. Our previous study found that the abundance of A. muciniphila was significantly higher in Ningxiang suckling piglets compared to other breeds, suggesting that early breast milk may play a crucial role. This study examines A. muciniphila's ability to utilize Ningxiang pig milk oligosaccharides. We discovered that A. muciniphila can thrive on both Ningxiang pig colostrum and purified pig milk oligosaccharides. Genetic analysis has shown that A. muciniphila harbors essential glycan-degrading enzymes, enabling it to effectively break down a broad spectrum of oligosaccharides. Our findings demonstrate that A. muciniphila can degrade pig milk oligosaccharides structures such as 3'-FL, 3'-SL, LNT, and LNnT, producing short-chain fatty acids in the process. The hydrolysis of these host-derived glycan structures enhances A. muciniphila's symbiotic interactions with other beneficial gut bacteria, contributing to a dynamic microbial ecological network. The capability of A. muciniphila to utilize pig milk oligosaccharides allows it to establish itself in the intestines of newborn piglets, effectively colonizing the mucosal layer early in life. This early colonization is key in supporting both mucosal and metabolic health, which is critical for enhancing piglet survival during lactation.

Dietary nutrition, intestinal microbiota dysbiosis and post-weaning diarrhea in piglets

Weaning is a critical transitional point in the life cycle of piglets. Early weaning can lead to post-weaning syndrome, destroy the intestinal barrier function and microbiota homeostasis, cause diarrhea and threaten the health of piglets. The nutritional components of milk and solid foods consumed by newborn animals can affect the diversity and structure of their intestinal microbiota, and regulate post-weaning diarrhea in piglets. Therefore, this paper reviews the effects and mechanisms of different nutrients, including protein, dietary fiber, dietary fatty acids and dietary electrolyte balance, on diarrhea and health of piglets by regulating intestinal function. Protein is an essential nutrient for the growth of piglets; however, excessive intake will cause many harmful effects, such as allergic reactions, intestinal barrier dysfunction and pathogenic growth, eventually aggravating piglet diarrhea. Dietary fiber is a nutrient that alleviates post-weaning diarrhea in piglets, which is related to its promotion of intestinal epithelial integrity, microbial homeostasis and the production of short-chain fatty acids. In addition, dietary fatty acids and dietary electrolyte balance can also facilitate the growth, function and health of piglets by regulating intestinal epithelial function, immune system and microbiota. Thus, a targeted control of dietary components to promote the establishment of a healthy bacterial community is a significant method for preventing nutritional diarrhea in weaned piglets.

Effects of Long-Term Coated Sodium Butyrate Supplementation on the Intestinal Health and Colonization of Cecal Salmonella of Laying Hens Infected with Salmonella enteritidis

Salmonella enterica ser. Enteritidis (S. Enteritidis) is widely found in chickens and eggs, and it can potentially induce human illness. The investigation in this study centers on the impacts of long-term dietary supplementation with coated sodium butyrate (CSB) on intestinal well-being and the colonization of cecum Salmonella in laying hens infected with S. Enteritidis. We segregated a total of 120 Lohmann laying hens aged 51 weeks into four treatment categories: 0 (CON), 300 (CSB1), 500 (CSB2), and 800 (CSB3) mg/kg of CSB, supplemented with CSB from the first day of the experiment. A 24-week observation process was carried out for each laying hen. The S. Enteritidis was orally administered to all chickens on the morning of the first and third days of week 22 of the trial. After the S. Enteritidis challenge, egg production decreased the most in the CON group. Compared to the CON group, the three doses of CSB significantly improved egg production after the S. Enteritidis challenge (PANOVA < 0.05). S. Enteritidis challenge increased plasma DAO activity, but CSB supplementation reduced plasma DAO activity (Plinear < 0.05). The S. Enteritidis challenge disrupted intestinal villi morphology; compared to the CON group, the three dosages of CSB resulted in an increase in villus height (VH) and the ratio of villus height to crypt depth (V/C) in the duodenum, jejunum, and ileum of infected laying hens (Plinear < 0.05), with a significant increase in jejunal villus height (PANOVA < 0.05). A decrease in ileal crypt depth was also observed (Plinear < 0.05). CSB2 and CSB3 markedly increased the content of butyric acid in the cecum (PANOVA < 0.05). Additionally, in contrast to those in the CON group, the propionic acid content in the CSB supplementation group increased (Plinear < 0.05). Compared with those in the CON group, mRNA relative expression of the IL-6 and IL-1β in jejunum (Plinear < 0.05) and mRNA relative expression of the IL-1β in ileum (PANOVA < 0.05) were significantly lower, and mRNA relative expression of the IL-10 in ileum (Plinear < 0.05) were significantly higher in the CSB group. In addition, in contrast to the CON group, the CSB supplementation group significantly upregulated mRNA relative expression of the ZO-1 and CLDN1 (PANOVA < 0.05). Additionally, CSB supplementation reduced the number of Salmonella and increased the number of Lactobacilli in the cecum (Plinear < 0.05) and tended to increase the total bacteria count (Plinear = 0.069) and reduce the E. coli count (Plinear = 0.081). In conclusion, long-term dietary supplementation with coated sodium butyrate can alleviate intestinal injury and the colonization of cecum Salmonella in laying hens infected with S. Enteritidis.

A review on the effect of soy bioactive components on growth and health outcomes in pigs and broiler chickens

While soy products have long been included in animal diets for their macronutrient fractions, more recent work has focused on the immunomodulatory potential of bioactive components of this feedstuff. This comprehensive review aims to identify the current state of knowledge on minor soy fractions and their impact on the health and growth of pigs and broiler chickens to better direct future research. A total of 7,683 publications were screened, yet only 151 were included in the review after exclusion criteria were applied, with the majority (n = 87) of these studies conducted in pigs. In both species, antinutritional factors and carbohydrates, like stachyose and raffinose, were the most frequently studied categories of bioactive components. For both categories, most publications were evaluating ways to decrease the prevalence of the examined components in soy products, especially when fed at earlier ages. Overall, most studies evaluated the effect of the bioactive component on performance-related outcomes (n = 137), followed by microbial analysis (n = 38) and intestinal structure and integrity measures (n = 37). As they were analyzed in the majority of publications, antinutritional factors were also the most frequently investigated category in relation to each specific outcome. This trend did not hold true for microbiota- or antioxidant-associated outcomes, which were most often studied with carbohydrates or polyphenols, respectively. Changes to the host microbiota have the potential to modulate the immune system, feed intake, and social behaviors through the microbiota-gut-brain axis, though few publications measured behavior and brain characteristics as an outcome. Other identified gaps in research included the study of soy saponins, as most research focused on saponins derived from other plants, the study of phytosterols outside of their role in cardiovascular or reproductive outcomes, and the general examination of bioactive peptides. Overall, given soy's popularity as a current constituent of animal feed, additional research into these bioactive components may serve to define the value of soy products through their potential ability to support the productivity, health, and well-being of animals.

Enzymolytic soybean meal improves growth performance, economic efficiency and organ development associated with cecal fermentation and microbiota in broilers offered low crude protein diets

The objective of this experiment was to determine the effect of low crude protein (CP) diets containing increasing amounts of enzymolytic soybean meal (ESBM) on growth performance, economic benefit and organ development and the role of cecal fermentation and microbiota in broilers. A total of 360 one-day-old Arbor Acres chicks were randomly allocated into 6 groups with 6 replicates and 10 chicks each. The six dietary treatments consisted of a standard high-CP diet (PC), a low-CP diet (NC), and an NC diet with 0.5, 1.0, 1.5%, or 2.0% ESBM. The experiment lasted for 42 days. Compared to PC, NC showed decreased (p < 0.05) average daily gain (ADG) in broilers from 22 to 42 days and from 1 to 42 days, while increasing levels of ESBM quadratically increased (p < 0.05) ADG from 1 to 42 days. Feed cost and total revenue in the NC were lower (p < 0.05) than that in the PC, while supplementation with ESBM in the NC linearly increased (p < 0.05) net profit and economic efficiency in broilers. There were significant differences (p < 0.05) in the liver, proventriculus and gizzard indices between the PC and NC groups, and supplementation with ESBM linearly increased (p < 0.05) the relative weights of liver, pancreas, proventriculus and gizzard in broilers at 42 days of age. The PC group had a higher cecal acetic acid concentration at 21 days and propionic acid concentration at both 21 and 42 days than the NC group (p < 0.05). Cecal acetic acid and propionic acid concentrations linearly increased (p < 0.05) with increasing levels of ESBM in broilers at 42 days of age. No significant differences in ACE, Chao1, Shannon and Simpson indices were observed among groups (p > 0.05), while the cecal abundances of Bacteroides, Faecalibacterium and Clostridium IV increased (p < 0.05) with the increasing level of ESBM in the low-CP diets. In conclusion, feeding ESBM improved economic efficiency, digestive organ development, cecal fermentation and microbial community composition, and up to 2.0% ESBM addition had no negative effect on the growth performance in broilers fed low CP diets.

Effect of enzymolytic soybean meal supplementation on performance, nitrogen excretion, serum biochemical parameters and intestinal morphology in broilers fed low-protein diets

OBJECTIVE

The objective of this study was to investigate the effect of supplementation with enzymolytic soybean meal (ESBM) on broilers fed low crude protein (CP) diets.

METHODS

A total of 360 one-day-old broilers were randomly assigned to six treatments with 6 replicates per treatment and 10 chicks per replicate for a period of 42 days. Chicks were fed a basal standard high-CP diet as a positive control (PC), a low-CP diet (reducing 10 g/kg CP from the PC) as a negative control (NC), or an NC + 0.5%, 1.0%, 1.5%, or 2.0% ESBM diet.

RESULTS

Compared to chicks fed the PC, chicks fed the NC had a decreased body weight gain (BWG, p<0.05) from 1 to 42 days, but supplementation with 2.0% ESBM restored BWG (p<0.05) and even linearly improved the feed conversion rate (FCR, p<0.05). Digestibility of CP and ether extract was increased (p<0.05) in chicks fed a 1.0% ESBM diet compared to the PC. With increasing levels of ESBM, nitrogen (N) excretion decreased (p<0.05). The addition of ESBM to the diet did not affect (p>0.05) serum concentrations of total protein, albumin and total cholesterol but led to a descending trend in triglycerides and an ascending trend in calcium and urea N at 42 days (p<0.10). There were no differences (p>0.05) in villus height (VH), crypt depth (CD), and VH/CD (V/C) of the duodenum and jejunum between the PC and NC at both 21 days and 42 days, while increasing dietary ESBM levels linearly (p<0.05) decreased CD and increased V/C of the duodenum and jejunum at both 21 days and 42 days.

CONCLUSION

The findings indicated that ESBM could be used in broiler low-CP diets to improve production performance, decrease N excretion, and enhance intestinal health.

Partial Substitution of Whey Protein Concentrate with Spray-Dried Porcine Plasma or Soy Protein Isolate in Milk Replacer Differentially Modulates Ileal Morphology, Nutrient Digestion, Immunity and Intestinal Microbiota of Neonatal Piglets

Appropriate protein sources are vital for the growth, development and health of neonates. Twenty-four 2-day-old piglets were randomly divided into three groups and fed isoenergetic and isonitrogenous diets. The experimental diets included a milk replacer with 17.70% whey protein concentrate (WPC group), a milk replacer with 6% spray-dried porcine plasma isonitrogenously substituting WPC (SDPP group), and a milk replacer with 5.13% soy protein isolate isonitrogenously substituting WPC (SPI group). Neonatal piglets were fed milk replacer from postnatal day 2 (PND 2) to day 20 (PND 20). The growth performance, intestinal morphology, activities of digestive enzymes, plasma biochemical parameters, immunity-related genes, short-chain fatty acids (SCFA) and intestinal microbiota in the colonic chyme were determined. The results showed that SDPP-fed piglets had higher final BW (p = 0.05), ADG (p = 0.05) and F/G (p = 0.07) compared with WPC- and SPI-fed piglets, and SDPP-fed piglets had a lower diarrhea index (p < 0.01) from PND 2 to PND 8. SDPP-fed piglets had an increased ileal villus height (p = 0.04) and ratio of villus height to crypt depth (VCR) (p = 0.02), and increased activities of sucrase (p < 0.01), lactase (p = 0.02) and trypsin (p = 0.08) in the jejunum, compared with WPC- and SPI-fed piglets. Furthermore, SPI-fed piglets had an increased mRNA expression of IL-6 (p < 0.01) and concentration of plasma urea (p = 0.08). The results from LEfSe analysis showed that SDPP-fed piglets had a higher abundance of beneficial Butyricicoccus compared with WPC- and SPI-fed piglets, in which higher abundances of pathogenic bacteria such as Marinifilaceae, Fusobacterium and Enterococcus were observed. Moreover, SDPP-fed piglets had an increased concentration of butyric acid (p = 0.08) in the colonic chyme compared with WPC- and SPI-fed piglets. These results suggest that neonatal piglets fed milk replacer with SDPP partially substituting WPC had improved growth performance and intestinal morphology and function, associated with higher digestive enzyme activity and fewer pathogenic bacteria.

Identification and Characterization of a Potential Probiotic, Clostridium butyricum G13, Isolated from the Intestine of the Mud Crab (Scylla paramamosain)

The butyrate-producing bacterium Clostridium butyricum has been proven to be important in improving the growth and health benefits of aquatic animals. In this study, C. butyricum G13 was isolated for the first time from the gut of the mud crab (Scylla paramamosain). The results of this study showed that C. butyricum G13 could produce a high concentration of butyric acid and grow well in a wide range of pHs (4 to 9) and NaCl (1 to 2.5%) and bile salt (0.2 to 1.0%) concentrations. In vitro characterization revealed that C. butyricum G13 is a Gram-positive and gamma-hemolytic bacterium sensitive to most antibiotics and shows hydrophobicity and the capacity to degrade starch. In vitro fermentation using mud crab gut contents showed that C. butyricum G13 alone or in combination with galactooligosaccharides (GOS) and/or resistant starch (RS) significantly increased butyric acid production and beneficially affected the abundance and diversity of intestinal microbiota. In addition, C. butyricum G13 can improve the survival rate of mud crabs and effectively maintain the normal structure of gut morphology after infection with Vibrio parahaemolyticus. In conclusion, C. butyricum G13 can be considered a potential probiotic that improves the immune capacity and confers health benefits on mud crabs. IMPORTANCE With the development of society, more and more aquatic animals are demanded. Intensification in the aquaculture scale is facing problems, such as disease outbreaks, eutrophication of water bodies, and misuse of antibiotics. Among these challenges, disease outbreak is the most important factor directly affecting aquaculture production. It is crucial to explore new approaches effective for the prevention and control of diseases. Probiotics have been widely used in aquaculture and have shown beneficial effects on the host. In this study, the butyrate-producing bacterium Clostridium butyricum G13 was isolated for the first time from the intestine of the mud crab through in vitro fermentation. The bacterium has probiotic properties and changes the gut microbiota to be beneficial to hosts in vitro as well as protecting hosts from Vibrio parahaemolyticus infection in vivo. The outcomes of this study indicate that C. butyricum G13 can be used as a potential probiotic in mud crab aquaculture.

Xylo-oligosaccharides improve the adverse effects of plant-based proteins on weaned piglet health by maintaining the intestinal barrier and inhibiting harmful bacterial growth

Introduction

Piglets are more susceptible to weaning stress syndrome when fed high levels of plant-based proteins that contain abundant food antigens and anti-nutritional factors. Xylo-oligosaccharides (XOS) are a potential prebiotic that may improve the tolerance of weaned piglets to plant-based proteins. The aim of this study was to investigate the effects of XOS supplementation in high and low plant-based protein diets on growth performance, gut morphology, short-chain fatty acid (SCFA) production, and gut microbiota of weaned piglets.

Methods

A total of 128 weanling piglets with an average body weight (BW) of 7.63 ± 0.45 kg were randomly allocated to one of the four dietary treatments in a 2 × 2 factorial arrangement, with two levels of plant-based proteins (d 1-14: 68.3 or 81.33%, d 15-28: 81.27 or 100%) and XOS complex (0 or 0.43%) over a 28-day trial.

Results

The growth performance of piglets did not differ significantly among groups (P > 0.05). However, the diarrhea index of weaned piglets fed a high plant-based protein diet (HP) was significantly higher than that of those fed a low plant-based protein diet (LP) at days 1-14 and throughout the experimental period (P < 0.05). XOS treatment tended to reduce the diarrhea index at days 1-14 (P = 0.062) and during the whole experiment period (P = 0.083). However, it significantly increased the digestibility of organic matter at days 15-28 (P < 0.05). Moreover, dietary XOS supplementation increased ileal mucosa mRNA expression of occludin and ZO-1 (P < 0.05). Furthermore, the concentration of butyric acid (BA) in the cecal contents and in the concentrations of BA and valeric acid (VA) in colon contents were significantly elevated in the XOS groups (P < 0.05). Additionally, XOS optimized the gut flora by lowering the number of pathogenic bacteria such as p_Campylobacterota, thereby stabilizing the gut ecosystem.

Discussion

In conclusion, the HP diet aggravated diarrhea in weaned piglets while the XOS diet alleviated it by improving nutrient digestibility, protecting intestinal morphology, and optimizing the gut flora.

Risk factors associated with post-weaning diarrhoea in Austrian piglet-producing farms

Post-weaning diarrhoea (PWD) is a frequent, multifactorial disease of piglets leading to increased mortality rates and high economic losses. Due to the emergence of multi-resistant Escherichia coli isolates and the ban of zinc oxide (ZnO) in the EU since June 2022, alternative measures to prevent PWD are urgently needed. While an abundance of feed supplements is described to prevent PWD, there are hardly any studies reflecting the current situation of PWD in the field. Thus, we aimed to identify differences in management practices, housing and feeding strategies between farms with PWD and farms without PWD. Data were personally collected using a semi-structured questionnaire in 257 Austrian piglet-producing farms. Farms with PWD in more than 10% of all weaned groups within twelve months prior to data collection were defined as case farms (n = 101), while the remaining 136 farms were defined as control farms. Data from 237 farms and 69 explanatory variables were analysed via penalized binary logistic regression using elastic-net in 100 different splits into randomly selected training and test datasets (80:20). Treatment with ZnO and/or colistin (136 farms) was negatively associated with PWD in all splits and had the biggest estimated absolute log odds ratio out of all tested variables. Implementation of an all-in/all-out system in the nursery units and administration of probiotics or horseradish also had preventive effects in most splits (≥ 97%). A higher number of feeding phases for piglets within the first seven weeks of life and housing on fully slatted floors was associated negatively with the occurrence of PWD as well in > 95% of all splits. PWD was more likely to occur on farms having problems with neonatal diarrhoea or postpartum dysgalactia syndrome. While our data demonstrate that treatment with ZnO or colistin had the biggest statistical effect on PWD, we were able to identify other preventive measures like supplementation with probiotics or horseradish. Since implementation of all-in/all-out measures and fully slatted floors were also negatively associated with the occurrence of PWD on visited farms, we assume that reduction of bacterial load by the implementation of simple hygiene measures are still crucial to prevent PWD.

Dietary inclusion of methanotrophic microbial cell-derived protein in the early post-weaning period sustains growth performance and intestinal health of weaner piglets

The global demand for sustainably produced protein feeds for animal production is increasing. Methanotrophic bacteria grow on methane and convert it into microbial cell protein (MCP) that has been shown to have high nutritive value for growing pigs. The present aimed to investigate how increasing amounts of MCP in diets fed during the first 15 days after weaning affect the growth performance of piglets from weaning until day 43 postweaning. Furthermore, the effect of MCP on intestinal morphology and histopathology was assessed on day 15 after weaning. During seven consecutive weeks, approximately 480 piglets were recruited for the experiment per batch. The piglets were divided into four groups and housed in eight double pens with 60 piglets per pen. The piglets were fed one of four experimental diets with 0, 3, 6, or 10% of MCP included at the expense of fishmeal and subsequently potato protein for the first 15 days postweaning. Thereafter, all pigs were fed commercial weaner diets in two phases (days 16-30 and days 31-43) until day 43 postweaning. All diets were without medicinal zinc. Feed intake and growth were registered on double pen level during all three phases. On day 15 after weaning, 10 piglets per treatment were randomly selected, autopsied, and sampled for intestinal morphology and histopathology. Daily gain during the first 15 days postweaning tended (P = 0.09) to be affected by the inclusion of MCP in the weaning diet being lowest in the group fed 10% MCP. Treatment did not affect daily feed intake; however, Feed Conversion Ratio (FCR) was significantly affected (P = 0.003) showing the highest FCR in piglets fed 10% MCP. Growth performance was not affected by the experimental treatment during the following phases. In the small intestine, villous height tended (P = 0.09) to show a quadratic response to level of MCP in the diet with the longest villi observed after feeding 6% MCP. Dietary treatment did not affect crypt depth. The villous height to crypt depth (VC) ratio showed a quadratic response to increased dietary inclusion of MCP (P = 0.02) with piglets fed 6% MCP having the highest VC ratio. In conclusion, this study demonstrated that MCP could constitute 6% of diets as-fed (22% of total CP), at the expense of fishmeal and potato protein, for newly weaned piglets without negative effects on growth rates and FCR. The inclusion of MCP in diets for newly weaned piglets could be part of improving the sustainability of pig production.

Dietary lysolecithin supplementation improves growth performance of weaned piglets via improving nutrients absorption, lipid metabolism, and redox status

Lysolecithin is widely used as emulsifier to improve the digestibility and retention of fat. The current study aimed to investigate the effects of dietary lysolecithin supplementation on growth performance, nutrients absorption, lipid metabolism, and redox status of weaned pigs. A total of 60 weaned piglets were assigned into 2 dietary treatments in a randomized complete block design, receiving basal diet with 0 or 1,000 mg/kg lysolecithin for a period of 28 d. Each dietary treatment had 10 replicates with 3 piglets per replicate. Growth performance and fecal score were monitored during trial. Samples of blood, ileum, and liver tissues were collected and analyzed for serology, intestinal histomorphology, and lipid metabolism-related gene and protein expressions. Dietary lysolecithin supplementation increased average daily gain (+15%, P < 0.05) and tended to increase average daily feed intake (+14%, P = 0.08) in overall experimental period. At final, the average body weight of piglets in lysolecithin group was 10% greater than that of control group (P = 0.09). In addition, dietary lysolecithin supplementation improved the ability of nutrients absorption as indicated by the higher d-xylose level in plasma (P < 0.05). Moreover, piglets from lysolecithin group had higher concentration of high-density lipoprotein (P < 0.05), but lower triglyceride (P < 0.05) in plasma. The inclusion of lysolecithin in diet increased the level of reduced glutathione (GSH) and GSH to oxidized glutathione (GSSG) ratio in plasma and liver (P < 0.05), but attenuated the levels of malondialdehyde and GSSG in ileum (P < 0.05). The upregulation of lipogenesis-related genes (FAS and ACC), downregulation of lipolysis (PNPLA2 and PABP1), and lipid mobilization (PGC-1α and SRIT1) genes were observed in lysolecithin relative to control piglets. Compared with control group, dietary lysolecithin supplementation upregulated protein expressions of GPX4, SREBP1, and LPL in liver and LPL in ileum (P < 0.05). Collectively, our study indicates that dietary lysolecithin supplementation improved growth performance of weaned piglets, which may be associated with the improved nutrients absorption, redox status, and lipid metabolism.

Degradation of soybean meal proteins by wheat malt endopeptidase and the antioxidant capacity of the enzymolytic products

This study investigated the hydrolysis effect of the endopeptidase from wheat malt on the soybean meal proteins. The results indicated that the endopeptidase broke the peptide bonds of soybean meal proteins and converted the alcohol- and alkali-soluble proteins into water-soluble and salt-soluble proteins. In addition, wheat malt endopeptidase did not break the disulfide bonds between proteins but affected the conformation of disulfide bonds between substrate protein molecules, which were changed from the gauche-gauche-trans (g-g-t) vibrational mode to the trans-gauche-trans (t-g-t) vibrational mode. Wheat malt endopeptidase exhibited the highest enzymatic activity at 2 h of enzymatic digestion, demonstrating the fastest hydrolytic rate of soybean meal proteins. Compared with the samples before enzymatic hydrolysis, the total alcohol- and alkali-soluble proteins were decreased by 11.89% but the water- and salt-soluble proteins were increased by 11.99%, indicating the hydrolytic effect of endopeptidase. The corresponding water-soluble proteins had molecular weights of 66.4-97.2, 29-44.3, and 20.1 kDa, while the salt-soluble proteins had molecular weights of 44.3-66.4, 29-44.3, and 20.1 kDa, respectively. The degree of enzymatic hydrolysis of soybean meal reached the maximum at 8 h. The newly created proteins exhibited significantly antioxidant properties, which were inversely related to the molecular weight. Proteins with molecular weight <3 kDa had the highest antioxidant performance with an antioxidant capacity of 1.72 ± 0.03 mM, hydroxyl radical scavenging rate of 98.04%, and ABTS [2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid)] radical scavenging capacity of 0.44 ± 0.04 mM.

Effects of coated sodium butyrate on performance, egg quality, nutrient digestibility, and intestinal health of laying hens

This study determined the effects of coated sodium butyrate (CSB) on production performance, egg quality, nutrient digestibility, and intestinal health of laying hens. We divided a total of 800 Lohmann laying hens, aged 51 wk, into 4 treatment groups: 0 (CON), 300 (CSB1), 500 (CSB2), and 800 (CSB3) mg/kg of CSB. Each group comprised 20 birds, with 10 replicates set. A 12-wk monitoring process was conducted for each laying hen. Compared to CON, dietary supplementation of CSB did not affect the average daily feed intake or the egg weight. The CSB3 group demonstrated a linear increase in the production performance (P < 0.05), with decreased feed conversion ratio (P < 0.05). CSB2 and CSB3 exhibited markedly elevated egg mass (P < 0.05). The CSB supplementation markedly enhanced the yolk color (P < 0.05). CSB1 improved the digestibility of dry matter (P = 0.029). No significant differences were observed among dietary treatments in the duodenal morphology (P > 0.05). The three dosages of CSB reduced the crypt depth (P < 0.05) in the jejunum, whereas CSB3 exhibited an increase in the villus height (VH; P = 0.048). The CSB3 group showed a markedly elevated ileal VH (P = 0.011). CSB supplementation significantly increased the butyric acid content in the cecum (P = 0.009). The hens fed on the 800 mg/kg CSB diet showed a significant increase (P = 0.029) in butyric acid content in the ileum. The CSB3 group showed an elevation in microbial diversity (P < 0.05). Additionally, at the phylum level, the CSB3 increased the enrichment of Bacteroidetes, the CSB2 increased Firmicutes, and the abundance of Deferribacteres was increased in CSB2 and CSB3 groups (P < 0.05). An enrichment of Muribaculaceae (family) was observed in the CSB3 group. In conclusion, dietary supplementation of CSB improved production, yolk color, intestinal morphology, butyrate content, and microbial composition in laying hens.