Crude Protein Digestibility Research Articles

Effect of protease supplementation on amino acid digestibility of soybean meal fed to growing-finishing pigs in two different ages.

This study was conducted to investigate the effect of protease inclusion level in two different ages on the apparent (AID) and standardized (SID) ileal digestibility of crude protein (CP) and amino acids (AA) in soybean meal (SBM) fed to growing-finishing pigs. Ten cannulated pigs (21kg ± 2kg) were assigned to experimental diets in a duplicate 5 × 5 Latin square design. In Phase I (23 to 30 kg-pigs, 90 ± 17 days of age), ileal digesta was collected in 5 periods of 7d (5d adaptation and 2d ileal digesta collection). In phase II, (50 to 65 kg-pigs, 140 ± 17 days of age), ileal digesta was collected in 5 more periods of 7 d. For both phases, a corn starch-based diet was formulated with SBM as the sole source of CP and AA and containing titanium as an indigestible marker. Protease was supplemented at 0, 15,000, 30,000, and 45,000 NFP/kg of feed (0, 25, 50, and 75g/ton of ProAct 360®). A nitrogen-free diet was used to estimate basal ileal endogenous AA losses. Pigs were fed at 4% of their body weight, which was adjusted at the end of each period. Orthogonal polynomial contrasts were used to determine the linear and quadratic effects of dietary protease supplementation in each phase. In phase I, increasing levels of protease resulted in a linear increase (P<0.10) in SID for the 7/11 indispensable AA (Except Arg, His, Met + Cys, and Trp) and the average of all dispensable AA. In phase II, the SID of Ile, Leu, Met, Met + Cys, Val, the average of all indispensable AA, and 4/7 dispensable AA were quadratically increased (P<0.10). In most cases, supplementation with 30,000 NFP/ kg of feed (50g/ton) resulted in the greatest increase in AA digestibility. However, the linear response in phase I for some AA suggests that diets for younger pigs could be supplemented with a greater level (45,000 NFP/kg or 75g/Ton of feed). Interestingly, younger pigs had consistently increased (P<0.10) SID of CP and 15/18 AA (Except Arg, Cys, and Ser), being ~5.6% greater for indispensable AA when compared to older pigs. In conclusion, dietary protease supplementation can increase the SID of AA in soybean meal in both growing and finishing periods. Pig age can potentially influence AA digestibility, possibly related to a greater ileal endogenous AA flow in younger pigs. However, this fact warrants further investigation.

Pregnancy affects maternal performance, feed intake, and digestion kinetics parameters in beef heifers.

This study aimed to quantify the effects of physiological status (PS) and potential interaction of this factor with days of pregnancy (DOP) on beef heifers' weight variation, intake, and digestion kinetics. Twelve rumen-cannulated zebu beef heifers (n = 7 pregnant; n = 5 non-pregnant) were used. Heifers were placed in individual pens and fed medium-quality corn silage plus a protein-based supplement. Heifers' body weight was assessed at the beginning and end of each collection period. The feed intake was measured daily. Target outcomes were evaluated at 107, 170, 208, 240, 267, and 286 days of pregnancy. The apparent total-tract digestibility was determined considering the fecal spot collection, during five days within each collection period. Omasal and ruminal digesta samples were collected at 107, 208, and 267 days of pregnancy for determination of partial digestibilities and diet component outflow. For these purposes, Co-EDTA and indigestible neutral detergent fiber (iNDF) were used as indicators. All data were analyzed using a mixed model framework, considering the PS and DOP as fixed effects and the animal as a random effect. Significant differences were declared when P ≤ 0.05. Pregnant heifers showed an increase in body reserves (+35kg) from 107 to 240 days of pregnancy, but experienced a decrease in shrunk body weight (-36kg) from 240 to 286 days of pregnancy. The intake of dry matter (DM), organic matter (OM), crude protein (CP), and ash- and protein-free neutral detergent fiber (apNDF) increased as pregnancy progressed (P < 0.04). The apparent total-tract digestibility of DM tended to be lower (P = 0.09), and the apparent total-tract digestibility of apNDF was reduced (P < 0.01) in pregnant heifers. The digestibility of CP was higher (P < 0.01) on days 267 and 286 in pregnant cows compared to non-pregnant heifers. The ruminal digestibility of OM tended to be lower (P = 0.09) in pregnant beef heifers, while the ruminal digestibility of apNDF was lower (P = 0.02) in pregnant heifers compared to non-pregnant ones. The ruminal pool of wet matter and DM was lower (P ≤ 0.01) in pregnant heifers at 267 days of pregnancy. In all periods, the outflow tended to be greater (P = 0.06) in pregnant heifers compared to non-pregnant heifers. Pregnant beef heifers exhibited a faster (P = 0.01) digesta passage rate during late gestation. In conclusion, late-gestating beef heifers are less efficient in extracting energy from feed compared to non-pregnant animals.

Enhancing growth performance and health of coloured-broiler chickens with signal grass meal (Brachiaria decumbens) supplementation under tropical conditions

This study examines the impact of signal grass (Brachiaria decumbens) as a phytobiotic supplement on the production performance and health of coloured-broiler chickens reared in tropical environments. A total of 216 day-old Sasso broiler chicks were randomly assigned to six treatment groups with six replications each. All six treatments received the same commercial diets with some adjustments: Treatment 1 (negative control) with only commercial feed, Treatment 2 (positive control) with 100 mg kg-1g kg-1 oxytetracycline, Treatment 3, 4, 5, and 6 with 1.25, 2.50, 3.75, and 5.00 g kg-1 of B. decumbens grass meal, respectively, without antibiotic. Throughout the eight-week study, body weight and feed intake were recorded weekly for each replicate to calculate body weight gain and feed conversion ratio. Additional evaluations included nutrient digestibility, gut histomorphology, cecal microflora population, carcass characteristics, and meat quality. Blood biomarkers and biochemistry were also analysed to evaluate the chickens' health status. Results indicated that broilers supplemented with B. decumbens grass meal, particularly T6 showed significantly (p<0.05) superior growth performance compared to the negative with reduced FCR of 6.8%. Apparent ileal digestibility was also significantly improved in T6, with 22.32% higher CP digestibility. Enhanced gut histomorphology and a healthier cecal microbial population supported improved nutrient absorption and overall gut health, as evidenced by significant increases in the villi-to-crypt ratio and a higher coliform count than the control. Enhanced carcass characteristics, such as higher full gizzard and gastrointestinal tract weights of T6 broilers, further supported improved digestibility. The supplementation also improved meat quality, with blood biomarkers indicating lower stress and inflammation levels comparable to T2. Additionally, the blood biochemistry of T6 broilers suggested hepatoprotective and hypocholesterolemic effects. Therefore, broilers in T6 demonstrated that B. decumbens has significant potential as an effective feed additive to replace antibiotics in the tropical poultry sector due to its phytocompounds profile, including high saponin content.

The Evaluation of Substituting Native Grass with Citronella Waste on the Digestibility of Dry Matter, Organic Matter, and Crude Protein in Ruminants Feeding

This study aims to determine the effect of substituting native grass with citronella waste on the digestibility of ruminants' dry matter, organic matter, and crude protein. A completely randomized design with 6 (six) treatments and 3 (three) replications is used in this research. The treatments were as follows: P1 = 50% native grass + 0% citronella waste + 50% concentrate; P2 = 40% native grass + 10% citronella waste + 50% concentrate; P3 = 30% native grass + 20% citronella waste + 50% concentrate; P4 = 20% native grass + 30% citronella waste + 50% concentrate; P5 = 10% native grass + 40% citronella waste + 50% concentrate; and P6 = 0% native grass + 50% citronella waste + 50% concentrate. The results showed that substituting native grass with citronella waste significantly affects (P&lt;0.01) the digestibility of dry matter, organic matter, and crude protein. The highest digestibility values were observed in the treatment using 100% native grass, with dry matter digestibility at 52.67%, organic matter at 56.58%, and crude protein at 67.55%. The study concludes that while native grass cannot be entirely replaced by citronella waste, it can substitute up to 50% of the complete feed when native grass availability is limited.

Effect of Dietary Crude Protein Reduction Levels on Performance, Nutrient Digestibility, Nitrogen Utilization, Blood Parameters, Meat Quality, and Welfare Index of Broilers in Welfare-Friendly Environments

We investigated the effects of feeding different levels of crude protein (CP) on broiler performance, blood characteristics, meat quality, nutrient and nitrogen (N) availability, stress levels, and welfare indicators in a welfare environment. A total of 625 eight-day-old male broilers were assigned to five dietary CP levels (control (CON) and 1–4% CP reductions) during the grower (8–21 days) and finisher (22–35 days) periods. The CON diet contained 20% CP in the grower phase and 19% in the finisher phase, while all birds received a 22% CP diet during the starter period (1–7 days). Intriguingly, reducing CP levels in the diet did not significantly affect growth performance. These results may be due to the adequate supplementation of essential amino acids in the diets of all treatments and the compensatory growth observed in the finisher phase. Low-CP diets reduced CP digestibility, N intake, and N excretion, while N retention efficiency improved (p &lt; 0.001). Serum total protein (TP) levels decreased equally with decreasing CP in the diet, and the crude fat content in meat increased linearly (p &lt; 0.01). The litter moisture content and pH decreased with lower CP levels, and the welfare indices (footpad dermatitis (FPD), serum corticosterone, etc.) improved (p &lt; 0.01). In conclusion, an appropriate reduction in CP levels in their diet can enhance broiler welfare by reducing N excretion and improving litter quality without adversely affecting performance.

Effect of Cashew Nutshell Extract, Saponins and Tannins Addition on Methane Emissions, Nutrient Digestibility and Feeding Behavior of Beef Steers Receiving a Backgrounding Diet

The beef industry contributes to greenhouse gas emissions through enteric methane emissions, exacerbating climate change. Anacardic acid in cashew nutshell extract (CNSE), saponins and tannins (ST) are plant secondary metabolites that show promise in methane mitigation via antimicrobial effects, potentially exerting changes in ruminal fermentation patterns. This study examined the impact of CNSE, ST, and their combination on methane emissions, digestibility, intake, and performance of sixteen Angus crossbred steers (347 ± 30 kg) receiving a backgrounding diet (70:30 corn silage: cottonseed burrs). The study used a 4 × 4 Latin square design (4 steers, 4 treatments, 4 periods) with a 2 × 2 factorial arrangement, including the main effects of additive (CNSE or ST) fed individually or combined. Thus, steers received the following treatments: (1) no additive, (2) CNSE only, (3) ST only, or (4) both (CNSEST). Non-supplemented steers registered eight more feedbunk visits/d than ST-steers and spent an extra 10 min/d on the feedbunk. The addition of ST tended to increase dry matter, organic matter, and neutral detergent fiber intake. Additives fed individually reduced CP digestibility. Intake of the carrier containing CNSE only was lesser and coincided with a greater methane yield in that treatment. Digestibility and methane mitigation were improved after CNSEST compared with individual inclusion, suggesting synergistic reactions enhanced methane mitigation effects in fibrous diets without affecting the digestibility of nutrients nor animal growth performance.

Development of Prediction Equations for Digestible and Metabolizable Energy in 15 Cereal Processing By-Products Fed to Growing Pigs

The study was conducted to determine the nutrient digestibility and digestible (DE) and metabolizable energy (ME) of 15 cereal processing by-products and to develop prediction equations for DE and ME based on the chemical composition in growing pigs. A total of 36 crossbred pigs were chosen and divided into three blocks according to a three 12 × 3 Youdin square experimental design. Twelve pigs in each block were allocated into six diets including a basal diet and five test diets. The feeding experiment included three periods, and each dietary treatment contained six replicates. Each period lasted 12 days, including 7 d of dietary adaption and 5 d of total feces and urine collection. The results showed that the coefficients of variation for EE, NDF, ADF, CP, and GE among 15 cereal processing by-products were 86.78%, 49.82%, 51.14%, 14.95%, and 6.26%, respectively. There were significant differences in DE, ME, and ME/DE (DM basis) among 15 cereal processing by-products (p &lt; 0.05), ranging from 11.55 MJ/kg to 17.64 MJ/kg, from 10.90 MJ/kg to 17.40 MJ/kg, and from 89.41% to 98.63%, respectively. The digestibility of GE, DM, NDF, ADF, and CP showed a significant difference among 15 cereal processing by-products (p &lt; 0.05). The DE and ME contents showed a negative correlation to NDF and ADF (p &lt; 0.05), and the prediction equations for DE and ME (as-fed basis) were DE (MJ/kg) = −0.4597 × ADF (%) + 0.5988 × GE (MJ/kg) + 6.0138 (R2 = 0.74; p &lt; 0.05) and ME (MJ/kg) = 1.0440 × DE (MJ/kg) − 1.1235 (R2 = 0.98; p &lt; 0.05). On a DM basis, the optimal prediction equations for DE and ME were DE (MJ/kg DM) = −0.1451 × NDF (%) + 0.3026 × CP (%) + 13.8595 (R2 = 0.72; p &lt; 0.05) and ME (MJ/kg DM) = 1.1155 × DE (MJ/kg DM) + 0.0363 × ADF (%) − 2.3412 (R2 = 0.99; p &lt; 0.05). In conclusion, there were large variations in the chemical composition, nutrients digestibility, and available energy among the 15 different samples of cereal processing by-products. It is reasonable to develop prediction equations for DE and ME based on the chemical composition of cereal by-products for growing pigs.

Growth performance and ruminal fermentation characteristics of Thai-native beef cattle fed cassava pulp fermented with Lactobacillus casei TH14 and additives.

Raw cassava pulp is a low-nutritional agro-industry residue with a high moist content that is susceptible to rot. Biodegradation of cassava pulp by adding Lactobacillus spp. plus stimulants could boost bio-acidity to preserve cassava pulp as ruminant feed. This investigation assessed the effect of ensiled cassava pulp without or with Lactobacillus casei TH14 (LTH14), urea, and molasses on the intake, digestibility, rumen fermentation, and growth performance of native Thai beef cattle. Eight Thai-native beef bulls (170.3 ± 20.2kg of initial body weight) were randomly assigned to two treatment groups in a completely randomized design: cassava pulp ensiled without additives (CPFNO; n = 4) and cassava pulp ensiled with the combination of LTH14 (2.5g per ton of fresh material), urea (4% DM), and molasses (4% DM) (CPFWA; n = 4). The intake of the concentrate diet and ensiled cassava pulp did not differ (p > 0.05) between the CPFNO and CPFWA groups, including final body weight, average daily gain (ADG), and feed conversion ratio (p > 0.05). However, CPFWA affected higher rice straw intake compared to the CPFNO group (p < 0.05). The intake and digestibility of crude protein (CP) were greater for the CPFWA group at 43.86% and 30.87%, respectively, compared to the CPFNO group (p < 0.05). Ruminal ammonia-nitrogen (NH3-N)and blood urea-nitrogen (BUN) were increased when animals were fed with CPFWA (p < 0.05). The average total volatile fatty acids (VFA) concentration of CPFWA was greater than that of CPFNO by 27.49% (p < 0.05). In conclusion, CPFWA supplementation can enhance rice straw intake, CP intake and digestion, total ruminal VFA concentration, and BUN levels, without adversely affecting growth performance.

Oregano essential oil and Bacillus subtilis role in enhancing broiler’s growth, stress indicators, intestinal integrity, and gene expression under high stocking density

This study investigates the role of dietary Bacillus subtilis and oregano essential oil in mitigating the effects of high stocking density on growth performance, carcass traits, physiological stress indicators, gene expression, and intestinal integrity in broiler chickens. A total of, 1250 one-day-old Ross 308 male broiler chicks were randomly allocated to five experimental groups, where each group had five replicates of 50 chicks. Group 1 (control, LSD): 15 chicks/m2 fed a basal diet without feed additive, group 2 (HSD): 20 chicks/m2 fed a basal diet without feed additive, group 3 (BHSD): 20 chicks/m2 fed a basal diet supplemented with B. subtilis (500 mg/kg diet), group 4 (OHSD): 20 chicks/m2 fed a basal diet supplemented with oregano essential oil (300 mg/kg diet), group 5 (CHSD): 20 chicks/m2 fed a basal diet supplemented with oregano essential oil and B. subtilis. At 35 days of age, there was a noticeable improvement in the growth performance of broilers fed CHSD under high stocking density through the increase in body weight gain, dressing percentage, and crude protein digestibility with a decrease in feed conversion rate compared to other groups. Adding CHSD enhanced the state of oxidation and immunity through increasing superoxide dismutase, glutathione peroxidase, and the relative weight of bursa of Fabricius, while decreasing malondialdehyde, in addition to increasing plasma triiodothyronine levels. The microbial structure and morphometric parameters improved in the group that received the CHSD compared to the other groups, where villus height and Lactobacillus population increased, whereas Escherichia coli and Clostridium perfringens population decreased. Glucose transporter 2 (GLUT2), fatty acid transporter 1 (FABP1), and amino acid transferase 1 (CAT1) gene expression levels significantly increased when feeding on oregano essential oil with B. subtilis. In conclusion, combining oregano essential oil and B. subtilis supplements mitigated the effects of high stocking density by enhancing growth performance, antioxidative status, and intestinal integrity, in addition to modifying the genetic expression of genes related to nutrient absorption.

Effects of dietary metabolizable energy and crude protein levels on laying performance, egg quality and fecal microbiota of Taihe Silky Fowl during the peak laying period.

The experiment aimed to study the effect of dietary metabolizable energy (ME) and crude protein (CP) on laying performance, egg quality, serum routine biochemical and lipid metabolism indicators, the apparent digestibility of nutrients, and fecal microbiota of Taihe Silky Fowl (TSF) during the peak laying period. A total of 540 26-week-old TSF female fowls were randomly allocated to 9 groups with 5 replicates per group and 12 fowls per replicate. The fowls were fed with a 3 × 3 factorial arrangement of treatments diets (ME:10.88,11.30, or 11.72 MJ/kg; CP: 15, 16, or 17%). With the increasing CP level, the egg weight (EW) (P=0.023), egg production (EP) (p=0.047), and egg mass (EM) (p=0.022) enhanced, while the feed conversion rate (FCR) (p=0.023) decreased. As the ME levels grew, the average daily feed intake (ADFI) (p<0.001) and FCR (p=0.045) decreased. With enhanced ME, the triglycerides (TG) (p=0.037), total cholesterol (TCHO) (p=0.041), and high-density lipoprotein cholesterol (HDL-C) (p=0.028) increased, whereas the low-density serum lipoprotein cholesterol (LDL-C) (p=0.039) decreased. The apparent digestibility of crude protein increased as the ME level increased (p= 0.029) and as the CP level decreased (p=0.027). At the same time, the apparent digestibility of gross energy increased as the ME level increased (p=0.018). Different levels of ME or CP changed the composition of fecal microbiota, 17% CP increased the abundance of Bifidobacterium. It is suggested that 10.88 MJ/kg dietary ME and 17% CP level are suitable for the nutritional requirements of TSF during the peak laying period.

Nutrient density and the collaborative impact of exogenous enzyme blend on the performance of broiler chicken.

This study evaluates the collaborative effect of exogenous enzyme blend and dietary nutrient density on the performance of broiler chicken. A total of 600 Ross 308 broiler chickens with same average initial body weight were randomly assigned to 5 treatments. Each treatment contained 8 replicates, and 15 birds per replicate. The diets included a control (CON) starter/finisher (S/F) diet with metabolizable energy (ME) 3,100/3,200 in Kcal/kg and crude protein (CP) content 22.0.0/20.00 in % as (S/F 3,100/3,200 Kcal/kg + CP, 22.00/20.00 %). S/F with ME 3,060/3,150 Kcal/kg + CP 21.50/19.50 % with and without the exogenous enzyme blend as (S/F 3,060/3,150 Kcal/kg + 21.50/19.50 % with, and without the exogenous enzyme blend), and lastly, S/F with ME 3,010/3,100 Kcal/kg + CP 21.50/19.50 % with, and without the exogenous enzyme blend as (S/F 3,010/3,100 Kcal/kg + 21.50/19.50 % with, and without the exogenous enzyme blend). The impact of the treatments was tested on growth performance, nutrient digestibility, blood metabolites, intestinal microflora, and morphology of broiler chicken. The inclusion of exogenous enzyme blend in the nutrient-deficient diet S/F 3,060/3,150 + 21.50/19.50 increased (p<0.05) broilers body weight, feed conversion ratio, nutrient digestibility of crude protein, gross energy, phosphorus, and blood phosphorus, with tendency (p<0.10) of higher dry matter. The treatment also showed lower (p<0.05) total anaerobic bacteria, coliform, and higher (p<0.05) villus height (VH) in the jejunum, with tendencies (p<0.10) of higher lactobacillus in the ileum and caecum, and higher tendency (p<0.10) of VH in duodenum and ileum. We concluded that the improved performance could be attributed to the potency of S/F 3,060/3,150 + 21.50/19.50 supplemented with 0.05% of the multienzyme to reduce the level of potential pathogenic bacteria with an increased level of positive bacteria, which in turn creates an enabling intestinal villi structure in broiler chicken.

Effects of insect meals on fish digestibility, blood parameters, and economic performance: a meta-analysis

Abstract This review examines the use of insect meal (IM) as a substitute for fishmeal (FM) in fish feeds within the past decade. While global interest in this alternative is growing, research on its effects on fish digestibility, blood parameters, and economic performance has been limited. Meta-analysis on the apparent digestibility coefficient revealed a negative effect summary on dry matter (−0.92) and crude lipid (−0.51), although the difference between the two groups was relatively minor. However, a positive effect summary was reported in the apparent digestibility of crude protein (0.12), suggesting a potential advantage in the utilization of protein by fish fed with IM-containing diets. Whereas meta-analysis on fish blood parameters demonstrates varying effects summary, necessitating further research. Analysis of economic performance revealed an overall better economic performance in the IM diet with an effect summary of −0.08 for feed cost and 0.00 for the economic profit index. Overall use of IM in aquafeed shows promise in improving feed quality and fish performance, potentially becoming a sustainable alternative to traditional FM. Recommendations include exploring IM’s impact on fish blood parameters through more investigations. Shifting focus from traditional measures to markers directly linked with fish health and immune response can provide more precise insights. Moreover, exploring various components of IM, such as lipids and functional elements like chitin, through simplified breakdown methods, can significantly enhance our comprehension of their nutritional value. Analyzing how each part influences fish health could pave the way for a sustainable and efficient alternative to FM in aquaculture.

Dietary β-mannanase reduced post-weaning diarrhea of pigs by positively modulating gut microbiota and attenuating systemic immune responses

BackgroundAfter weaning, nursery pigs have difficulty digesting non-starch polysaccharides in their diets, which can result in growth and health problems. Among non-starch polysaccharides, β-mannan is easily found in various cereal grains that form the basis of livestock diets and interferes the digestion and utilization of nutrients. Supplementation of dietary β-mannanase in nursery diet can alleviate the negative effects on nutrient utilization efficiency caused by β-mannan and improve growth and health of pigs. This study was conducted to evaluate effects of dietary β-mannanase supplementation on growth performance, nutrient digestibility, intestinal morphology, fecal microbiota, and systemic immune responses of weaned pigs.ResultsDietary β-mannanase (MAN) improved average daily gain (P = 0.053), average daily feed intake (P < 0.05), and gain to feed ratio (P = 0.077) of pigs for 3 weeks after weaning and apparent total tract digestibility of crude protein (P = 0.060) and reduced post-weaning diarrhea (P < 0.05). The MAN did not affect the ileal morphology. Pigs fed with MAN had more diverse fecal microbiota based on the results of alpha diversity [the number of operational taxonomic units (OTUs; P = 0.061), Shannon (P = 0.071), and Simpson indices (P = 0.078)] and relative abundance of phylum Bacteroidetes (P = 0.064) and genus Prevotella (P < 0.05) than pigs fed control diet (CON). As a result of beta diversity, fecal microbiota was clustered (P < 0.05) into two distinct groups between dietary treatments. The MAN decreased (P < 0.05) packed cell volume (PCV), the number of white blood cells (WBC), C-reactive protein (CRP), tumor necrosis factor-α (TNF-α), transforming growth factor-β1 (TGF-β1), and cortisol of the pigs for 2 weeks after weaning compared with CON.ConclusionDietary β-mannanase reduced post-weaning diarrhea of pigs by positively modulating gut microbiota and attenuating systemic immune responses.

Standardized Ileal Digestibility of Amino Acids in Hybrid Rye Ground to Two Particle Sizes and Fed With or Without Multienzyme Supplement to Young Growing Pigs.

A newly developed hybrid rye with enhanced ergot resistance has potential as an alternative energy source for pigs. An experiment was conducted to evaluate the effects of particle size (PS) and multienzyme supplement (MES) on the apparent total tract digestibility (ATTD) of energy and nutrients and the standardized ileal digestibility (SID) of amino acids (AA) in hybrid rye fed to growing pigs. Bono and Gatano, two hybrid rye varieties, were ground to either a coarse (1111 and 1210 μm) or a fine (594 and 717 μm) PS using a hammer mill. Eighteen ileal-cannulated barrows (initial BW = 18.2 ± 1.0 kg) were randomly assigned to 1 of 9 dietary treatments in a replicated 9 × 3 incomplete Latin square design to give six observations per treatment. Among the nine experimental diets, eight featured two hybrid rye varieties (Bono or Gatano), either coarsely or finely ground, as the only source of AA with or without MES, while an N-free diet was used to estimate the endogenous losses of AA at the distal ileum. All diets contained titanium dioxide as an indigestible marker. Each period lasted 9 days, with the first 5 days being for adaptation followed by 2 days each for faecal and ileal digesta collection. Data were analysed using the MIXED procedure of SAS, with the final model having variety, PS, MES, their two-way interactions, and a three-way interaction. No interactions were noted except that the apparent ileal digestibility and SID of crude protein (CP) and most AA in Gatano had greater effects of MES than Bono (Variety × MES; p < 0.05). The ATTD of dry matter (DM), gross energy (GE) and CP were greater (p < 0.05) in Bono diets than in Gatano diets. Finely ground hybrid rye diets had higher (p < 0.05) ATTD of neutral detergent fibre assayed with a heat stable amylase and expressed inclusive of residual ash (NDF) and ether extract compared to coarsely ground hybrid rye diets. Dietary MES supplementation increased (p < 0.05) the ATTD of DM, GE, CP, NDF, acid detergent fibre expressed inclusive of residual ash, and ash in hybrid rye diets. In conclusion, the nutrients digestibility of hybrid rye can be affected by its variety. PS reduction improved the nutrient digestibility in hybrid rye, and MES supplementation improved the energy and AA digestibility in hybrid rye fed to growing pigs.

Impact of varying levels of soy hulls and β-mannanase enzyme supplementation on growth performance, carcass characteristics, nutrient utilization and blood biochemical profile in broiler chickens

Two hundred and forty day-old broilers were randomly assigned to six experimental groups in a 2 x 3 factorial design. The birds were fed diets containing soybean hulls (SH) at the levels of 4% and 6% and β-Mannanase (BM) at the concentration of 0%, 0.05% and 0.1%. Results indicated significant effects of SH and BM supplementation on body weight (BW) and weight gain (WG), with birds fed 4% SH and 0.1% BM exhibiting higher (p < 0.05) body weight and weight gain compared to other groups. Feed conversion ratio (FCR) was improved (p < 0.05) in birds receiving 4% SH with 0.1% BM supplementation. However, no significant effects were observed on carcase traits across treatment groups. Regarding nutrient digestibility, birds supplemented with 0.1% BM showed improved (p < 0.05) crude protein (CP) digestibility compared to those without BM supplementation. No significant variations were observed in dry matter, crude fibre and ether extract utilisation among treatment groups. Hematological and serum biochemical parameters were not influenced by SH and BM supplementation, indicating no adverse effects on blood parameters. In conclusion, these findings underscore the potential advantages of incorporating 4% SH and 0.1% BM in broiler diets for enhanced growth performance and nutrient utilisation.

Effects of Oregano on Lactation Performance, Nutrient Digestibility, Ruminal Fermentation Parameters, and Methane Emissions in Dairy Cows: A Meta-Analysis

Growing concerns regarding antibiotic use in livestock, due to antibiotic resistance and potential human transmission, have led to increased interest in herbs and their derivatives, including essential oils, which possess antimicrobial properties that may enhance overall productivity and serve as a strategy for methane mitigation. The objective of this meta-analysis was to investigate the effects of adding oregano to the diet in different forms (essential oils, plant materials, or leaves) on the dry matter intake (DMI), milk yield (MY), milk components, nutrient digestibility, ruminal fermentation parameters, and methane (CH4) emissions of dairy cows. A literature search was conducted to identify papers published from 2000 to 2023. Effect size for all outcomes was reported as a standardized means difference (SMD) and raw means difference with 95% confidence intervals. Heterogeneity was determined using the Q test and I2 statistic. The results of the meta-analysis indicated that adding oregano had no effect on DMI (SMD = 0.081; p = 0.507) and MY (SMD = 0.060; p = 0.665). Milk fat percentage, milk protein percentage, and milk lactose percentage were not affected by oregano. The addition of oregano to the diet significantly decreased dry matter digestibility (SMD = −0.502; p = 0.013), crude protein digestibility (SMD = −0.374; p = 0.040), and neutral detergent fiber digestibility (SMD = −0.505; p = 0.014). Ruminal pH (SMD = −0.122; p = 0.411), total volatile fatty acids concentration (SMD = −0.038; p = 0.798), acetate (SMD = −0.046; p = 0.757), propionate (SMD = 0.007; p = 0.960), and butyrate (SMD = 0.037; p = 0.801) proportion were not affected by oregano. The addition of oregano to the diet tended to decrease CH4/DMI (SMD = −0.275; p = 0.095) but did not affect CH4 production (SMD = −0.156; p = 0.282). Heterogeneity (Q and I2) was non-significant for all parameters. We conclude that the inclusion of oregano in various forms (essential oils, plant materials, or leaves) in the diet of dairy cows reduces nutrient digestibility but does not significantly affect DMI, MY, milk components, ruminal fermentation parameters, or CH4 production. Future research should focus on optimizing the dosage of oregano (both EOs and plant materials) and exploring the impact of its form on lactation, nutrient digestibility, ruminal fermentation, and CH4 emissions in dairy cows.

Implication of dietary barberry (Berberis Vulgaris) leaves inclusion on growth performance, nutrient digestibility, and carcass traits in ostriches

This study determined production performance, nutrient intake, digestibility, and carcass traits from ostrich chicks fed with barberry (Berberis Vulgaris) leaves (BVL) as a replacement for alfalfa hay (AH). For 150 days, 30 male ostrich (Struthio camelus) (9.10 ± 0.89 kg live weight, mean ± SD) were randomly grouped into five dietary BVL inclusion levels to replace AH: a control diet based on 100% AH (CTRL), and four groups with BVL as a substitute for AH at varying levels including 25% (BVL25), 50% (BVL50), 75% (BVL75), and 100% (BVL100). The average daily feed intakes (ADFI) were recorded and birds were weighed monthly. The nutrient intake and digestibility were measured for the following final 5 days of the trial. The ADFI was higher (p = 0.025) for BVL100 and BVL75 than for CTRL. Ostriches fed on BVL50 had the highest average daily gain (ADG, p = 0.025) and the lowest feed conversation ratio (FCR, p = 0.0001). Return per kg BW gain was also enhanced (p = 0.018) with BVL50 feeding. Dietary BVL levels did not affect the digestibility of OM (p = 0.257), CP (p = 0.260), EE (p = 0.610), CF (p = 0.427), and Ash (p = 0.461). Also, there were no changes in AME (p = 0.180) or AMEn (p = 0.670). The hot carcass weight (HCW, p = 0.331) and dressing BW (p = 0.237) were not affected. Overall, the results suggest that BVL can replace AH in ostrich diets without deleterious impact on performance, however, its partial substitution (for 50% AH of diet) has been associated with improved ADG, FCR, and reduced feeding costs.

An emerging role of ferulic acid on sub-adult grass carp (Ctenopharyngodon idellus): Increasing protein digestion and regulating amino acid and oligopeptide transporters expression

This study was conducted to evaluate the effect of supplement ferulic acid on growth performance, digestive ability and transport function of amino acids and oligopeptides in the intestine of sub-adult grass carp (Ctenopharyngodon idellus). The experiment was divided into two parts: a. Digestion experiment: healthy grass carp (678.83±1.00 g) were divided into two groups: control group (0 mg/kg FA) and ferulic acid group (100 mg/kg FA) for 2 weeks; b. Growth experiment: healthy grass carp (678.83±1.00 g) were divided into five treatment groups, the control group (FA0) with no ferulic acid and the experimental group supplemented with ferulic acid 50 (FA50), 100 (FA100), 150 (FA150) and 200 (FA200) mg/kg feed for 9 weeks. The results showed that a. Ferulic acid supplementation increased the apparent digestibility of crude protein and crude fat in grass carp. b. Ferulic acid supplementation improved the growth performance and feed efficiency (FE) of grass carp; increased the activities of trypsin and Na+/K+-ATPase; and up-regulated the levels of mRNAs of some neutral and cationic (non-anionic) amino acid transporter proteins (Solute Carrier Family7member1 (SLC7A7), SLC7A8, etc.) and H+/oligopeptide transporter protein 1 (PepT1) gene and protein levels. In addition, ferulic acid promoted the gene expression levels of protein kinase B (Akt), target of rapamycin (TOR); up-regulated the mRNA levels of tail-side-associated homologous frame transcription factor 2 (Cdx2), cAMP response element-binding protein (CREB), and transcriptional co-activator-specific protein 1 (Sp1), and down-regulated the gene and protein levels of protein kinase CβII (PKCβII). In a word, dietary ferulic acid promoted growth performance, digestion, as well as amino acid and oligopeptide transport capacities. Finally, based on regression analyses of percentage weight gain (PWG), FE, specific growth rate (SGR), intestine fold height, trypsin activity, and Na+/K+-ATPase activity, we recommend optimal supplementation levels of ferulic acid in sub-adult grass carp of 92.18–120.60 mg/kg diet.

Effects of Chitosan-Based Additive on Rumen Fermentation and Microbial Community, Nutrients Digestibility and Lactation Performance in Goats.

Recently, the potential of using chitosan (CHI) as a feed additive to enhance ruminal fermentation and improve animal performance has gained increasing attention in ruminant nutrition. This study was undertaken to investigate the effect of dietary supplementation with increasing doses of CHI on rumen fermentation attributes and microbial composition, digestibility and milk performance in Dhofari goats. Twenty-four lactating goats (27 ± 1.8 kg of initial live body weight) were fed a control diet comprising of Rhodes grass hay plus a concentrate feed mixture. Goats were assigned to one of three experimental treatments (n = 8 per treatment) as: (1) control diet with no supplement (CTRL), (2) control diet with 0.300 g/day CHI (CHI0.3) and (3) control diet supplemented with 0.600 g/day CHI (CHI0.6) for a 45-day experimental period. Dietary supplementation with increasing doses of CHI decreased (p < 0.05) linearly ruminal pH (p = 0.023), total short chain fatty acids concentrations (p = 0.011), acetate (p = 0.013) and butyrate (p = 0.042) proportions, acetate to propionate ratio (p < 0.001), estimated methane (CH4) production (p < 0.001), ammonia nitrogen concentrations (p = 0.003) and protozoa abundance (p = 0.003). However, the ruminal propionate proportion augmented (p = 0.002) linearly with increasing doses of CHI in the diet. Increasing doses of CHI linearly increased the abundance of the ruminal propionate-producing bacteria, while diminished acetate and CH4-producing bacteria (p < 0.05). Serum total protein (p = 0.037) and glucose (p = 0.042) levels linearly increased as CHI doses increased in the diet. However, serum UREA levels decreased linearly (p = 0.002) by 21% with increasing CHI amounts in the diet. The digestibility of organic matter, crude protein and neutral detergent fibre increased linearly with the increasing CHI doses (p < 0.05). Neither linear nor quadratic responses (p > 0.05) were observed in daily milk yield and feed efficiency by supplementing the diet with CHI. In conclusion, supplementing the diet with CHI at a dose of 0.600 g/day as a feed additive for dairy goats reduced estimated CH4 generation and improved fibre and protein digestion, with no influence on feed intake, milk yield or composition.

Effects of Alanyl-Glutamine Dipeptide Supplementation on Growth Performance, Nutrient Digestibility, Digestive Enzyme Activity, Immunity, and Antioxidant Status in Growing Laying Hens.

Alanyl-glutamine (Aln-Gln), a highly soluble and stable Glutamine-dipeptide, is known to improve the performance of poultry birds. This study aimed to investigate the effect of Aln-Gln during the rearing period on growth performance, nutrient digestibility, digestive enzyme activity, immunity, antioxidant status and relative gene expression of Hy-Line brown hens. A total of 480 healthy day-old Hy-line brown chicks with similar body weights were randomly divided into four dietary groups (8 replicates/group and 15 birds/replicate). Groups A, B, C and D were fed diets containing 0%, 0.1%, 0.2% and 0.3% Aln-Gln, respectively, for 6 weeks. The body weight (BW) and average daily gain (ADG) were higher in hens fed test diets compared with the control (p < 0.05). The feed conversion ratio (FCR) was better in test groups as compared to the control group (p < 0.05). The ADFI showed no significant difference between the groups. Dietary treatments had no effect on dry matter (DM), organic matter (OM) and crude fiber (CF) digestibility. The Aln-Gln also improved gross energy (GE) and crude protein (CP) digestibility (p < 0.05). It has also increased IgG levels in groups C and D. IgM levels were similar to the control in B, C and D. The Aln-Gln increased IL-1 in B and C, IL-2 in C and D, and IL-6 in all test groups (p < 0.05). The supplementation of Aln-Gln had no effect on serum antioxidant indices like CAT, MDA, GSH-PX, GSH, and SOD in 42-day-old growing hens. Aln-Gln supplementation had no significant effect (p > 0.05) on the activity of amylase and lipase, however, a significant improvement (p < 0.05) in the activities of trypsin and chymotrypsin was observed in the test groups. Supplemented Aln-Gln levels in the birds' diets led to an increase in the expression of genes related to growth factors (IGF-1, IGFBP-5), immune markers (IL-1, IL-2, IL-6) and antioxidant status (GSH-Px1), as compared to control group. Aln-Gln supplementation in Hy-Line brown hens during their growing period improved growth, nutrient digestibility, immunity and digestive enzymes activity. These findings suggest that Aln-Gln is a promising dietary additive for enhancing poultry performance.