Technical note: concentrations of soluble, insoluble, and total dietary fiber in feed ingredients determined using Method AOAC 991.43 are not different from values determined using Method AOAC 2011.43 with the AnkomTDF Dietary Fiber Analyzer

Dietary fiber supplementation during the last 50 days of gestation improves the farrowing performance of gilts by modulating insulin sensitivity, gut microbiota, and placental function

Our previous study found dietary konjac flour (KF) supplementation could improve insulin sensitivity and reproductive performance of sows, but its high price limits its application in actual production. This study aimed to investigate the effects of supplementation of a cheaper combined dietary fiber (CDF, using bamboo shoots fiber and alginate fiber to partially replace KF) from the last 50 days of gestation to parturition on farrowing performance, insulin sensitivity, gut microbiota, and placental function of gilts. Specifically, a total of 135 pregnant gilts with a similar farrowing time were blocked by backfat thickness and body weight on day 65 of gestation (G65d) and assigned to 1 of the 3 dietary treatment groups (n = 45 per group): basal diet (CON), basal diet supplemented with 2% KF or 2% CDF (CDF containing 15% KF, 60% bamboo shoots fiber, and 25% alginate fiber), respectively. The litter performance, insulin sensitivity and glucose tolerance parameters, placental vessel density, and short-chain fatty acids (SCFAs) levels in feces were assessed. The gut microbiota population in gilts during gestation was also assessed by 16S rDNA gene sequencing. Compared with CON, both KF and CDF treatments not only increased the piglet birth weight (P < 0.05) and piglet vitality (P < 0.01) but also decreased the proportion of piglets with birth weight ≤ 1.2 kg (P < 0.01) and increased the proportion of piglets with birth weight ≥ 1.5 kg (P < 0.01). In addition, KF or CDF supplementation reduced fasting blood insulin level (P < 0.05), homeostasis model assessment-insulin resistance (P < 0.05), serum hemoglobin A1c (P < 0.05), and the level of advanced glycation end products (P < 0.05) at G110d, and increased the placental vascular density (P < 0.05) at farrowing. Meanwhile, KF or CDF supplementation increased microbial diversity (P < 0.05) and SCFAs levels (P < 0.05) in feces at G110d. Notably, the production cost per live-born piglet was lower in CDF group (¥ 36.1) than KF group (¥ 41.3). Overall, KF or CDF supplementation from G65d to farrowing could improve the farrowing performance of gilts possibly by improving insulin sensitivity, regulating gut microbiota and metabolites, and increasing placental vascular density, with higher economic benefits and a similar effect for CDF vs. KF, suggesting the potential of CDF as a cheaper alternative to KF in actual production.

Effects of fiber type, particle size, and inclusion level on the growth performance, digestive organ growth, intestinal morphology, intestinal viscosity, and gene expression of broilers

The aim of this study was to evaluate the effect fiber type, particle size, and inclusion level on the performance parameters, intestinal development and gene expression in broiler chickens. A total of 648 one-day old Cobb male broilers were randomly assigned to a control diet and 8 other dietary treatments divided in 2 fiber types (cellulose vs. soyhulls), 2 particle sizes (100 and 600 µm), and 2 inclusion levels (4 and 8% crude fiber). Birds were reared to 21 days of age in battery cages (n = 6 replicates). Growth performance parameters and intestinal viscosity were measured on da 7, 14, and 21. On d 14 and 21, digestive organ weights were recorded for analyses of organ growth. On d 21, intestinal samples were taken for analyses of histology, and jejunal mucosas were collected for analyses of nutrient transporters. Data were analyzed as a 2 × 2 × 2 factorial design using JMP 2021. Treatments were compared against the control group using one-way analysis of variance, whereas the main effect interactions were evaluated as a factorial excluding the control group to be able to assess the effect of the independent variables without the variability introduced by the control group. The groups fed 8% crude fiber from cellulose (8% CL) had the lowest weight gain regardless of the particle size (P < 0.01). The control group had the highest feed intake among the treatments (P < 0.01). The groups fed 8% crude fiber from soyhulls (8% SH) with a coarse particle size had the heaviest relative gizzard weight among the treatments (P = 0.045). The groups fed 8% SH had the heaviest small intestine weights regardless of the particle size (P = 0.009). No differences were observed in the relative weights of the ceca. The highest viscosity was observed in the group fed 8% SH with a fine particle size (P < 0.001). The group fed 4% SH with a coarse particle size had the longest duodenal villus (P < 0.001). The shortest jejunal villus height was observed in the group fed 8% CL with a fine particle size (P < 0.001). Ileal villus was highest in the groups fed high CL levels regardless of the particle size (P < 0.001). The highest digestibility of dry matter was observed in the group 4% SH with fine particle (P = 0.017). The group 4% CL with fine particle had the highest digestibility of crude protein (P = 0.033). The highest expression of peptide transporter 1 was observed in the group fed 8% CL with a coarse particle size (P = 0.008). In conclusion, fiber type, particle size, and inclusion levels are important factors in the regulation of intestinal morphology, viscosity, nutrient transporters, and growth performance.

Evaluation of energy values of high-fiber dietary ingredients with different solubility fed to growing pigs using the difference and regression methods

The objective of this study was to compare the energy values of high-fiber dietary ingredients with different solubility (sugar beet pulp [SBP] and defatted rice bran [DFRB]) in growing pigs using the difference and the regression methods. A total of 21 barrows (initial BW, 40.5 ± 1.2 kg) were assigned to 3 blocks with BW as a blocking factor, and each block was assigned to a 7 × 2 incomplete Latin square design with 7 diets and two 13-d experimental periods. The 7 experimental diets consisted of a corn-soybean meal basal diet and 6 additional diets containing 10%, 20%, or 30% SBP or DFRB in the basal diet, respectively. Each of the experimental periods lasted 12 d, with a 7 d dietary adaptation period followed by 5-d total fecal and urine collection. Results showed that the digestible energy (DE) and metabolizable energy (ME) of the SBP determined by the difference method with different inclusion levels (10%, 20%, or 30%) were 2,712 and 2,628 kcal/kg, 2,683 and 2,580 kcal/kg, and 2,643 and 2,554 kcal/kg DM basis, respectively. The DE and ME in the DFRB evaluated by the difference method with 3 different inclusion levels were 2,407 and 2,243 kcal/kg, 2,687 and 2,598 kcal/kg, and 2,630 and 2,544 kcal/kg DM basis, respectively. Different inclusion levels had no effects on the energy values of each test ingredient estimated by the difference method. The DE and ME of the SBP and the DFRB estimated by the regression method were 2,562 and 2,472 kcal/kg and 2,685 and 2,606 kcal/kg DM basis, respectively. The energy values of each ingredient determined by the regression method were similar to the values estimated by the difference method with the 20% or 30% inclusion level. However, the energy values of the SBP and DFRB estimated by the difference method with the 10% inclusion level were inconsistent with the values determined by the regression method (P < 0.05). In conclusion, the regression method was a robust indirect method to evaluate the energy values for high-fiber ingredients with different solubility in growing pigs. If the number of experimental animals was limited, the difference method with a moderate inclusion level (at least 20%) of the test high-fiber ingredient in the basal diet could be applied to substitute the regression method.

Role of Dietary Fiber in Poultry Nutrition

Simple Summary

Dietary fiber is an inherent compound found in common vegetables that are fed to broiler chickens. Fiber has the ability to scape digestion and absorption in the small intestine, which makes it able to affect the way other nutrients are absorbed and metabolized in the gastrointestinal tract. The functionality attributed to fiber varies based on chemical and physical structure, and most of the time, it is hard to make a clear differentiation among attributes due to the complexity of carbohydrates found in common feedstuffs. Data on the effect of dietary fiber have been gaining importance due to the use of grains for ethanol production and the search for feed alternatives that could help in sustainable and cost-effective broiler production. Therefore, it is paramount to integrate the current knowledge on the nutritional and physiological attributes of dietary fiber in poultry diets to be able to make correct use of fibrous feedstuffs.

Abstract

Dietary fiber (DF) is an intrinsic component in plant feedstuffs that has been associated with physiological, structural, and functional changes in the gastrointestinal tract. DF is composed of non-starch polysaccharides (NSP), oligosaccharides, and lignin that scape digestion and enzymatic hydrolysis. In general terms, fiber can be classified as insoluble or soluble based on their solubility in water. Both fiber types have direct nutritional implications in broiler diets. Inclusion of insoluble DF in broiler diets modulates intestinal morphology, digestive organ development, nutrient absorption, growth performance, and intestinal microbiota. Soluble DF is thought to increase intestinal viscosity and is associated with negative changes in intestinal microflora and reduction in nutrient absorption. Nevertheless, there is a group of soluble fibers, integrated by oligosaccharides, that function as prebiotics positively modulating intestinal microbiota. Due to the changes in chemical structure and subsequent variation in functionality, it is a difficult task to assign clear attributes to DF as a whole. Therefore, the following review paper compiles data from research conducted using DF and tries to unify such information into practical decisions to be considered when using DF as a functional nutrient in poultry nutrition.

Effects of Collection Durations on the Determination of Energy Values and Nutrient Digestibility of High-Fiber Diets in Growing Pigs by Total Fecal Collection Method

Simple Summary

The total fecal collection method is the gold standard to estimate the energy values and nutrient digestibility of the swine diet. However, there is no standard collection duration for animals that should be sampled in swine research using the total fecal collection method. Thus, this study aimed to investigate the effects of different collection durations (3-day, 5-day, or 7-day) on energy values and nutrient digestibility of high-fiber diets in growing pigs by time-based total fecal collection method. The results showed that the digestible energy (DE), metabolizable energy (ME), and apparent total tract digestibility (ATTD) of gross energy (GE) and most nutrients in diets decreased linearly as the collection duration increased from a 3-day to a 7-day collection. However, there were no differences in the ATTD of GE and nutrient between the 5-day and 7-day collection durations. In addition, the energy values and the ATTD of GE and nutrient of high-fiber ingredients (sugar beet pulp (SBP) or defatted rice bran (DFRB)) were also not affected by the collection durations. Therefore, the results of this research suggest that a 5-day collection duration is adequate to determine the energy values and the ATTD of nutrient in diets containing high-fiber ingredients for growing pigs by time-based total fecal collection method.

Abstract

This study was conducted to evaluate the effect of collection durations on the energy values and nutrient digestibility of high-fiber diets in growing pigs with a time-based total fecal collection method. A total of 24 barrows (body weight (BW): 31.1 ± 1.5 kg) were allotted to a completely randomized design with three diets. Diets included a corn–soybean meal (CSM) basal diet and two additional diets containing 20% sugar beet pulp (SBP) or defatted rice bran (DFRB) by replacing corn, soybean meal, and soybean oil in the CSM diet, respectively. Each diet was fed to eight barrows for a 7-day adaptation period followed by a 7-day total feces and urine collection period. The 7-day collection duration was divided into three collection phases, namely, phase 1 (days 8 to 11), phase 2 (days 11 to 13), and phase 3 (days 13 to 15). Then, similar portions of feces and urine from the different collection phases were composited into three additional samples (days 8 to 11, days 8 to 13, and days 8 to 15, respectively). The results showed that the digestible energy (DE), metabolizable energy (ME), and apparent total tract digestibility (ATTD) of gross energy (GE) and nutrient in experimental diets decreased linearly as the collection durations increased from a 3-day to a 7-day collection (p < 0.05). However, there were no differences in the energy values, GE, and nutrient digestibility of diets and of high-fiber ingredients between the 5-day and 7-day collection durations. In conclusion, this study suggests that a 5-day collection duration is adequate to determine the energy values and nutrient digestibility of high-fiber diets containing SBP or DFRB in growing pigs by the time-based total fecal collection method.