Digestibility Coefficients Research Articles

Impacts of alfalfa nutrient concentrate on pellet physical attributes, growth performance, metabolism and nutritional quality of rainbow trout, Oncorhynchus mykiss

This study addresses the escalating demand for aquatic feed by exploring the potential of alfalfa nutrient concentrate (ANC) as feed ingredient for rainbow trout. Test diets contained varying ANC levels (0%, 5%, 10%, 15%, and 20%) to replace fishmeal (32% in the 0% ANC diet) to achieve equal digestible protein and were processed using a cooking extrusion method. Analysis of feed pellets showed that pellet density increased with ANC levels (P < 0.001), resulting in sinking pellets at 20% ANC. Water stability and durability were improved while oil leakage decreased with increasing ANC levels (P < 0.05). Two feeding trials were conducted to test the diets in flow-through water systems with three replicates per diet. The first 10-week trial evaluated their impact on feeding, fecal physical quality, and the apparent digestibility coefficient (ADC) of dietary nutrients in rainbow trout (initial body weight , 18.0 ± 0.2 g). ANC inclusion did not impact the palatability and satiety feed intake of the fish (P > 0.05). However, the ADC of dry matter and phosphorus significantly decreased in fish fed the 20% ANC diet (P < 0.05). The second 9-week trial investigated the growth performance, nutrition quality, and metabolism of rainbow trout (initial body weight, 19.0 ± 0.2 g). While all fish exhibited substantial growth, fish fed diets with 10% to 20% ANC displayed lower specific growth rate and higher feed conversion ratio compared to those fed with 0% or 5% ANC (P < 0.05). The whole body protein content was higher in fish fed 5% ANC compared to all other treatments (P = 0.030). The biochemical parameters of plasma were similar across treatments, except for a decrease in plasma phosphorus levels in fish fed a 10% ANC diet compared to those fed a 0% ANC diet. (P = 0.033). Significant changes were observed in liver metabolism including tricarboxylic acid cycle, amino acid and energy metabolism pathways in fish fed the 20% ANC diet versus the 0% ANC diet (P < 0.05). These results demonstrate that ANC inclusion improved pellet physical quality without impairing feeding behavior and nutritional quality of the fish but inclusion ≥10% in the diet reduced fish growth. This study offers the first comprehensive assessment of the potential of ANC used in fish feed involving feed management, feeding evaluation, and the biological response.

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.

Effect of Using Prickly Pear Seed Cake (Opuntia ficus indica L.) on Growth Performance, Digestibility, Physiological and Histometric Parameters in Rabbits

Prickly pear (Opuntia ficus indica L.) could be used in rabbit nutrition in compliance with circular economy principles, global warming issues, and reduction of production costs. This study aims to evaluate the effects of dietary incorporation of prickly pear seed cake (PPSC) on growth, physiological, and histometric parameters in rabbits. A total of 105 rabbits were divided into three experimental groups (n = 35) and fed different diets: a commercial feed (C group), the same feed with alfalfa replaced by PPSC at 10% (10PP group), and at 20% (20PP group). They were group-housed in cages with 5 animals per cage from weaning until slaughtering. While body weights and weight gains were similar in all groups, the coefficients of nutrient digestibility of dry matter, fibers, and ashes, as well as the characteristics of intestinal villi, were improved in the 10PP group compared to the others (p &lt; 0.05). The 20PP group showed a reduction in perirenal and interscapular fat (p &lt; 0.05), as well as lower plasma concentrations of triglycerides and cholesterol compared to the C group (p &lt; 0.001). In conclusion, PPSC can be incorporated into the diets of growing rabbits up to 20% as a partial substitute for alfalfa without the impairment of growth performance. Additionally, the inclusion of PPSC enhanced nutrient digestibility and increased the intestinal absorption surface area.

Assessment of two diet types in reduced-crude protein diets with or without phytase supplementation – implications on key phenotypic responses in 21-day-old broiler chickens

ABSTRACT 1. Two concurrent experiments were conducted to investigate the effect of using the crude protein (CP) value of supplemental amino acids (AA) in formulating reduced-crude protein (RCP) diets. The RCP diets formulated without accounting for CP values of supplemental AA (RCPN) or otherwise (RCPY) or a positive control (PC) diet were fed without (Experiment 1) or with (Experiment 2) phytase. 2. Each experiment utilised 105 male broiler chicks. Birds were provided a common starter diet from d 0–7. On d 21, ileal digesta were collected from the distal half of the ileum. For mRNA expression analysis, tissues were collected from the mid-jejunum and the liver. Excreta grab samples were collected for analysis for N content. 3. In Experiment 1, there was a stepwise decrease (p < 0.01) in weight gain and excreta N for birds receiving PC, RCPN and RCPY diets. The coefficients of ileal digestibility of His, Leu, Phe and Trp were greater (p < 0.05) in birds that received RCPY rather than the PC diets. The relative mRNA expression of CAT1 was greater (p < 0.05) for birds that received the PC diet. 4. In Experiment 2, growth performance and excreta N were not different between the PC and RCPN diets, but weight gain, feed intake and excreta N were greater (p < 0.01) in birds receiving PC or RCPN diets. The coefficients of digestibility were greater (p < 0.01) in RCP than PC diets for Lys, Thr, Cys, Gly and Ser. The mRNA expression for S6kinase and PRKAβ2 was greater (p < 0.05) for birds fed RCPN compared to PC. 5. In conclusion, accounting for the N content of supplemental AA during feed formulation for RCP diets will influence the effect of CP reduction on growth performance and ileal amino acid digestibility.

Efectiveness of growing simmental breed cares with diferent maintenance technologies.

The purpose of the work was to establish the features of meat productivity of Simmental breed bulls depending on the rearing technology: 1 - traditional technology used on farms (indoors); 2 - using feeding and final fattening. The rearing technology had a significant impact on the live weight of bull calves and the amount of gain at different age periods. The difference in live weight between groups I and II was: at 6 months – 11.2 kg (P &gt; 0.99); at 14 months – 20.3 kg (P &gt; 0.999); at 18 months – 43.9 kg (P &gt; 0.999) in favor of bulls of the second experimental group. On average, by the age of one and a half years, bulls of group II were 43.9 kg heavier than their peers of group I. At 18 months of age, the digestibility coefficients in both groups were high, but in young animals of group II, the coefficients of fiber digestibility were 18.2 % and fat 17.9 % higher than in group I bulls. The best slaughter qualities were in bulls reared using fattening and final fattening. The bulls of group II compared to group I had heavier carcasses: at the age of 6 months by 7.4 kg, at 14 months by 14.5 kg, and at 18 months by 37.0 kg. The deposition of internal fat was relatively small and somewhat greater in bulls of group II. At the age of 14 months, the carcass weight of group II bulls was greater than group I by 6.74 %, and the pulp by 1.34 %. This difference persisted at 18 months. The type of feeding had a significant impact on bone strength. The load that caused bone fractures in volume-fed bulls averaged 1,477 kg, and with concentrated feeding, an average of 1,209 kg, or 18 % less.

Bioactive compounds enrichment in rabbit doe’s diet pre-and during pregnancy improves productive and reproductive performance and cost-effectiveness under hot climates

This study aimed to investigate the effect of diet supplementation with a symbiotic (SY), bee pollen (BP), honey bee (HB), date palm pollen (DPP) and their mixture (MIX) on female rabbit productive and reproductive performances under desert hot climates. Seventy-two Californian does of 5 months age and average body weight of 3250 ± 78.2 g were randomly allotted into six groups, each of 12 does. All does orally receive 3 ml distilled water for 10 days before mating and 28 days during pregnancy. Treatments were repeated for four consecutive parities. The first group served as control (C) given distilled water only, however the second, third, fourth and fifth groups were supplemented with 3 ml distilled water containing 0.2 ml SY, 200 mg DPP, 200 mg BP, 0.2 ml HB/doe per day, respectively. While, the sixth group does were given all previous ingredients (MIX). Sexual receptivity rate, fertility rate, kindling rate, and newborn traits were recorded. Also, maternal feed intake, feed conversion ratio, and digestibility coefficients of nutrients were recorded. Does in all groups were artificially inseminated with 0.5 ml of fresh heterospermic semen of 15 fertile bucks extended in Tris at 806–1006 sperm/ml. Treatment increased maternal body weight and daily gain with highest values (P < 0.05) in BP, SY, and MIX does. All treatments enhanced feed intake and feed conversion ratio (FCR) compared with control. Number services per conception decreased (P < 0.01), while litter size and weight and survival at birth and weaning increased (P < 0.01) in treated than control does. Treated does produced more milk than control. Digestibility coefficients of all nutrients were improved (P < 0.01) in treated does. In conclusion, supporting rabbit does pre- and during pregnancy with diets supplemented with a mixture of honey bee, date palm pollen, bee pollen, and synbiotic improves the productive and reproductive performances of rabbit does and their offspring.

Dietary superdosing of phytase positively affects growth, mineral utilization and amino acid availability of channel catfish (Ictalurus punctatus)

The present study investigated the effects of supplementing high levels (superdosing) of dietary phytase on growth performance, mineral utilization and digestibility of amino acids in different regions of the gastrointestinal (GI) tract of fingerling channel catfish. The negative control (NC) diet was formulated with primarily soybean meal as a protein feedstuff which contributed 0.61 % total phosphorus (P) but was deficient in available P at 0.11 % of diet. Five other diets were formulated either with supplemental monocalcium phosphate at 1 % of diet in the positive control (PC), or supplemented with Quantum Blue phytase (AB Vista, Plantation, Florida) at 1000, 2000, 4000, or 8000 phytase units (FTU)/kg of diet. Groups of 20 catfish were each stocked into 24 aquaria operated as a closed, recirculating system with biological and mechanical filtration. All dietary treatments were assigned randomly to quadruplicate aquaria and initially fed at 6 % of total body weight per day. Feed quantities were adjusted weekly after weighing all fish in each aquarium as a group, and feeding levels were maintained close to apparent satiation throughout the 8-week feeding trial. Phytase supplementation significantly (P < 0.05) increased various responses of channel catfish including weight gain, feed efficiency, and protein retention compared to catfish fed the NC diet, resulting in values that were similar to catfish fed the PC diet. Moreover, catfish fed the phytase-supplemented diets had higher bone ash, calcium (Ca), magnesium (Mg), P, manganese (Mn), and zinc (Zn), as well as retention of Ca, Mg, P, iron (Fe), Mn, and Zn in whole-body tissues. Additionally, apparent availability of P from the posterior intestinal region increased with dietary phytase supplementation, with reduced excretion of nitrogen, Ca, Mg, P, copper (Cu), Mn, and Zn observed in comparison to fish fed the NC diet. Apparent digestibility coefficients for many of the indispensable and dispensable amino acids were increased by phytase supplementation, except for histidine, methionine, threonine, and taurine. This improvement in amino acid availability occurred only in the posterior region of the gastrointestinal tract. Channel catfish fed the diet containing 4000 FTU/kg diet had the highest postprandial plasma phosphorus level most of the time, except at 24 h after feeding. Based on these various responses, the optimal dietary phytase dosage was determined to average 5492 FTU/kg diet.

The effects of dietary supplementation with red grape pomace treated with ozone gas on ruminal fermentation activities, nutrient digestibility, lactational performance, and blood metabolites in dairy ewes

This study aimed to investigate the effect of red grape pomace (RGP) treated with ozone (O3) gas as a substitute of low-quality alfalfa hay on the ruminal fermentation, nutrient digestibility, and milk production performance of fat-tailed, fed RGP substituted high fibrous alfalfa hay. Present study was performed in two experimental phases: 1) In situ and in vitro phase: Four Ghezel ewes in their third gestation (30 months old; weighing 51 ± 2 kg) with surgically implanted cannulas in their rumen were used to assess the in situ degradability and to obtain ruminal fluid to assay the in vitro gas production; the treatments were RGP not-processed (control; T0), and RGP processed with O3 for 6 (T1), 12 h (T2), and 24 h (T3). Processing RGP with O3 gas reduced (P < 0.05) neutral detergent fiber (NDF) and acid detergent fiber (ADF), although the processing time did not show differences. Ozone-treated RGP caused a reduction (P < 0.02) in total phenolics, total tannins, condensed tannins, protein-bound tannins, and fiber-bound tannins, compared to the control. Processing RGP with O3 for 12 h improved the nutritional value of RGP because of the reduction of the concentration of phenolic compounds, the increase of the in vitro gas production and the dry matter (DM) degradability, and improved fermentation parameters and it was chosen for the second phase of the experiment. 2) In vivo phase: Forty-eight healthy multiparous fat-tailed Ghezel ewes received the control diet (0 % RGP), or diets that substituted 20, 40, and 60 % of the dietary alfalfa hay with RGP processed with O3 for 12 h. Incremental dietary replacement of RGP with alfalfa hay did not influence the ruminal total volatile fatty acids but increased (P < 0.03) propionate. The digestibility coefficients of the DM and the NDF increased (P < 0.001) in diets containing RGP versus the control, but not for the crude protein and ether extract. The ruminal protozoa population exhibited a linear increase with the addition of O3-treated RGP (P < 0.001). Plasma glucose and albumin concentration increased (P < 0.04), and milk production and milk fat, protein, and lactose contents also increased (P < 0.05) with the alfalfa substitution with O3-processed RGP. In conclusion, replacing high-fibrous alfalfa hay with RGP treated with O3 for 12 h improved the apparent digestibility of DM and NDF and maintained the performance of the ewes.

Effect of acid and fermented silage hydrolysis time on protein fractionation and digestibility for Nile Tilapia

World aquaculture production currently demands sustainable protein ingredients that can compete with fishmeal regarding nutritional quality and economic feasibility. In this study, the protein fractionation of silages prepared with Nile tilapia processing waste (heads, spine, fins, and viscera) by two processes and three hydrolysis times was evaluated, considering the digestibility coefficients of its crude protein, amino acids, and gross energy of Nile tilapia juveniles. The apparent digestibility coefficients (ADCs) were determined using 360 Nile tilapia juveniles (9.36 ± 0.74 g) distributed in 18 tanks (150 L), following a completely randomized design with six treatments, in a factorial scheme of 2×3, with three replicates. The six test diets were composed of 69.5 % of the reference diet, 0.5 % chromium (III) oxide, and 30 % of either acid or fermented silages produced with three hydrolysis times (24, 96, and 192 hours). The results demonstrated that both the processing type and hydrolysis time influenced the profile and peptide fractions of the silages. The acid silage was faster in relation to the release of free α-amino groups and the degree of hydrolysis (DH), up to 192 hours of hydrolysis. After this period, the fermented silage showed a higher degree and speed of hydrolysis. SDS-PAGE demonstrated that a longer hydrolysis time increased the concentration of the protein band between 150 and 100 kDa, indicating a proliferation of microorganisms using the free amino acids produced during fermentation. Regarding the distribution of peptides, acid silage presented higher values for the concentration of polypeptides, slow degradation and proportion among fractions, with the appearance of di- and tripeptides, as well as free amino acids. For the fermented silage, a higher degradation of polypeptides into oligopeptides was verified, representing the highest fraction, with a small proportion of di- and tripeptides and free amino acids. ADC values were high for all amino acids and proteins, which was not observed for the mean values of energy ADC. The production of silages with 192 hours of hydrolysis proved to be viable, and the fermented processing revealed the highest ADC values in relation to most of the amino acids, thus being the most indicated to be incorporated in fish diets, favoring its utilization by small farmers and reducing the inadequate disposal of biodegradable waste, thereby avoiding environmental pollution.

Bacillus licheniformis and phytase combination in broiler chicken diets: Effects on growth performance, digestibility coefficients, gut microbiome activities, and bone quality

In the present study, B. licheniformis was added to broiler chicken diets alone or in combination with 6-phytase and the effects on growth performance, coefficients of ileal nutrient digestibility, morphometrical measurements of selected internal organs, gut microbial activity, and bone quality were determined. Four hundred 1-day-old female birds (Ross 308) were randomly allotted to 4 dietary treatments (10 replicate pens, 10 birds each). The trial was set up as follows: negative control (NC), basal diet without any feed additive; NC+Pro, basal diet with B. licheniformis (500 g/t of diet); NC+Phy, basal diet with 6-phytase (400 g/t of diet); and NC+Pro+Phy, basal diet in which both experimental factors were added at the same levels as above. The interaction between treatments was noted in each evaluated period regarding BWG and FI. In the entire experiment, an increased body weight gain (P < 0.001) was observed in the NC+Pro+Phy treatment compared to the other groups. The birds that received both feed additives combined were characterized by an increased feed intake (P < 0.001), contrary to NC+Pro and NC+Phy. Moreover, in terms of microenvironment modulations, interactions (P < 0.05) were observed in the jejunal and cecal digesta pH, short-chain fatty acid (SCFA) level, and microbial enzyme activities. However, the impacts of B. licheniformis and phytase on cecal SCFA concentrations and bacterial enzymes were mainly opposite. There were no interactions (P < 0.05) in terms of geometrical, mechanical, and structural selected tibia and femur indices. However, 6-phytase addition improved bone structure, stiffness, and elasticity. In conclusion, the interactions between 6-phytase and B. licheniformis positively affect growth performance via microbial activity changes; however, the supportive bone quality maintenance properties are only connected to 6-phytase supplementation.

Influence of different levels of black soldier fly larvae meal on growth performance and carcass quality of broiler chickens

A study was conducted to examine the impact of two inclusion levels of Black soldier fly larvae meal (BSFLM) replacing soybean meal on growth performance, nutrient utilization, carcass characteristics and meat quality of broilers. Three experimental diets based on corn-soybean meal were developed to contain 0 (control), 6 (BSF 6) and 12% (BSF 12) BSFLMfor both starter and grower phases. Each experimental diet was randomly allotted to six replicate pens (eight birds per pen). The birds were offered starter pellets from 0 to 14 day post-hatch and grower pellets from 15 to 28 day post-hatch. The experimental diets were tested for pellet durability index (PDI). There was an interaction between diet and growth phase (P < 0.001) for pellet durability index where starter diets had always a higher PDI than the grower diets, but the difference was greater for control diet than BSF 6 and BSF 12 diets. Apparent metabolizable energy (AME) of diets and coefficients of apparent ileal digestibility (CAID) of nutrients were measured on day 28 using titanium dioxide marker ratios in the diet and excreta/ileal digesta. On day 28, the weights of live body, carcass, fat pad, breast and gizzard were recorded, and then breast meat quality (meat pH, drip loss and cooking loss) was examined. Inclusion of BSFLM of up to 12% did not reduce live weight gain or feed intake. Live weight and carcass weight were heavier in broilers fed 12% BSFLM than controls (P < 0.02), but were not different than those fed 6%, while controls were not different than those fed 6%. Breast weight (percentage live weight) was lower in birds offered 12% BSFL than in others (P < 0.04). No differences were observed between diets for the percentage weight as carcass, fat, pad and gizzard. The AME and AMEc of diets were the highest in broilers fed 6% BSFLM diet (P < 0.005), but there were no differences between controls and those fed 12% BSFLM. The CAID of DM, ash and N in birds fed 6% BSFLM were greater than (P < 0.03) birds fed 12%, but were not different than controls, which were also not different than those fed 12%. Broiler breast meat quality was unaffected by dietary treatments. In conclusion, BSFLM at 12% can be used effectively as a SBM replacement in starter and grower diets, without affecting the growth performance, nutrient utilization, carcass characteristics and meat quality of broiler chickens.

Dog Breed and Starch Gelatinisation Correlation in Food Digestibility and Faecal Traits.

Large dog breeds commonly produce unformed faeces. The present study hypothesised that foods for large dog breeds require higher starch gelatinisation (SG) to reduce organic matter flow to colon. Fifteen Rottweilers (Ro; 49.4 ± 6.12 kg), 18 Beagles (Be; 12.13 ± 1.75 kg) and 20 Shih-Tzus (ST; 4.62 ± 1.15 kg) were fed one of three diets, all based on the same sorghum formulation, processed to obtain three levels of SG: SG90 (91.8% SG), SG50 (50.7% SG) and SG30 (27.4% SG). Foods were provided for 23 days, and the coefficient of total tract apparent digestibility (CTTAD) of nutrients, faecal production and fermentation products, Na, K and Cl apparent absorption and gastrointestinal transit time (GTT) were evaluated. Results were submitted to analysis of variance considering SG, breed and their interactions, and means compared by the Tukey test (p < 0.05). All dogs promptly ate the foods. Faeces scores were lower for Ro than for Be and ST, and lower for SG30 than SG90 (p < 0.05). Faeces pH was higher, and total short-chain fatty acids were lower for SG90 than for SG50 and SG30 (p < 0.01), regardless of breed. No diet effect was observed for GTT (p > 0.05), but it was lower for Ro (41.7 ± 6.2 h) than for ST (48.7 ± 8.6 h). The CTTAD of nutrients was lower for SG30, intermediary for SG50 and higher for SG90 (p < 0.05), and among breeds CTTAD was higher for Be than ST and Ro (p < 0.05), which did not differ from each other, except for crude protein CTTAD which was lower for Ro (p < 0.05). The apparent absorption of Na and K was higher for the SG90 treatment, and for Be in comparison with Ro and ST (p < 0.05). Food SG had a remarkable influence on Ro faeces formation and on the CTTAD in all breeds. Greater fermentation in the colon and lower protein CTTAD may be involved in Ro unformed faeces formation.

Nutritional evaluation of an aqueous-processed canola protein concentrate in diets of Atlantic Salmon Salmo salar at different life stages

A novel aqueous processing method was applied on canola defatted meal to produce a protein concentrate (>76 % crude protein, dry matter basis). This aqueous-processed canola protein concentrate (ACPC) was evaluated in three experiments with Atlantic salmon. The objectives were to (1) estimate the nutrient digestibility of ACPC in juvenile fish, (2) appraise its nutrient digestibility in post-smolt salmon, and (3) evaluate the long-term effect of ACPC on growth, survival, nutrient utilization, body composition, fillet pigmentation and gut histology of post-smolt salmon. In the first study, one Reference and one test diet, which was a blend of 70 % Reference and 30 % ACPC (70:30 ratio), were fed to juvenile salmon (57 ± 7 g) and feces were collected using settling columns. In the second study, post-smolt salmon (228 ± 4 g) were fed one Reference and three test diets, which consisted of three Reference to ACPC ratios: 90:10, 80:20 and 70:30. Feces were collected by manual stripping. The long-term study (168 days) was designed as a 2 × 4 full factorial analysis with two types of formula (Americas, with processed animal proteins (PAPs), and Europe, without PAPs) and four inclusion levels of ACPC (0, 10, 15, 20 %) fed to post-smolt Atlantic salmon (228 ± 5 g). Fish were bulk weighed every 28 or 56 days. Distal intestine and fillet were sampled (10 fish/tank) at the end for histological examination and color measurement, respectively. All diets (43–49 % crude protein, 18–25 % crude lipid depending on studies) were extruded and fed to apparent satiation. The apparent digestibility coefficients (ADCs) of ACPC protein in juvenile and post-smolt salmon were 89 % and ≥ 94 %, respectively. The essential amino acids ADCs in juvenile and post-smolt salmon were 83–99 % and 91–99 %, respectively. ACPC protein digestibility was not significantly affected by its inclusion level (P = 0.470). In the third experiment, growth (TGC: 0.143–0.160) and feed intake (668–780 g/fish) were not significantly affected by ACPC inclusion (P ≥ 0.10). Feed conversion ratios varied between 1.04 and 1.08. An unexpected occurrence of disease caused 1.6 % mortality over three weeks during the 24-week long-term study and survival was significantly higher in salmon fed ACPC-containing diets (P < 0.001). ACPC inclusion significantly increased fillet redness (P < 0.001) and increased villus length of distal intestine (P < 0.001). In conclusion, ACPC was a safe and nutritive protein alternative in salmon diets, regardless of inclusion level.

A blend of bacillus-fermented soybean meal, functional amino acids, and nucleotides improves nutrient digestibility, bolsters immune response, reduces diarrhea, and enhances growth performance in weaned piglets.

This study investigated the effects of a blend of bacillus-fermented soybean meal, functional amino acids, and nucleotides (Functional protein blend-FP Blend) as a replacement for animal protein sources in a weaner pig diet without antibiotic growth promoters on nutrient digestibility, blood profiles, intestinal morphology, diarrhea incidence, and growth performance. A total of 288 crossbred weaned piglets [♂ Duroc x ♀ (Yorkshire × Landrace)] with an average body weight (BW) of 6.89 ± 0.71kg were randomly allocated to 6 groups based on initial BW and sex (8 replicate pens per treatment; 3 gilts and 3 barrows/pen). The experiment lasted for 5wk. Dietary treatments included PC [standard diet with 3% fish meal (FM) and 2% plasma protein (PP)], NC (nonanimal protein, AP), T1 (3% FM replaced with 5% FP Blend), T2 (3% FM and 1% PP replaced with 5% FP Blend), T3 (2% PP replaced with 5%FP Blend), and T4 (3% FM and 2% PP replaced with 5% FP Blend). Data were analyzed using Minitab version 17 software. Key results indicated that FP Blend improved the apparent ileal digestibility (AID) coefficient of dry matter, gross energy, lysine, and valine in T4 compared with NC treatment (P < 0.05), whereas AID coefficient of crude protein and other amino acids remained constant (P > 0.05). Compared with NC diet, the weaned pigs fed T4 diet reduced malondialdehyde, serum IL8, TNF-α, and increased IgG (P < 0.05), while showing no effect on serum IL6, IL10, white blood cells, IgA, and endotoxin (P > 0.05). Furthermore, FP blend significantly increased villus height in the duodenum and ileum in T4 compared with NC (P < 0.05). The average daily gain (ADG) was highest in T4 (502.73g/d), followed by T1 (477.96g/d) and T2 (475.85g/d), compared with PC (450.86g/d) and NC (439.79g/d). T4's ADG significantly differed from PC and NC (P < 0.001), whereas no significant differences were observed in T1, T2, and T3 (P > 0.05). The feed conversion ratio (FCR) was significantly lower in T4 (1.45) compared with PC (1.57) and NC (1.59) (P < 0.001), with no significant differences among other groups. In conclusion, FP Blend demonstrated efficacy in improving nutrient digestibility, optimizing intestinal morphology, bolstering immune responses, reducing diarrhea incidence, alleviating the adverse effects of weaning stress, and enhancing growth performance of weaned piglets.

Full-fat black soldier fly larvae meal and yellow mealworm meal: Impact on feed protein quality, growth and nutrient utilization of Atlantic salmon (Salmo salar) post smolts

The shift towards insect-based alternatives in aquafeeds stems from the need to reduce the carbon footprint associated with the ingredients used in salmon feeds. In the present study, we describe the effects of full-fat insect meal incorporation on amino acid derivatives in feeds and the growth performance and nutrient utilization of Atlantic salmon post-smolts fed insect meals. A 74-day growth trial was conducted employing 520 fish (143 ± 12.8 g); these fish were fed either a control diet (CO) that contained 20 % fishmeal, 20 % soy protein concentrate (SPC), 14 % wheat gluten, 19 % plant raw materials, 13 % fish oil and 6 % rapeseed oil, or one of four insect meal diets, prepared with either 5 % and 10 % black soldier fly larvae meal (BS5, BS10) or 15 % and 30 % mealworm meal (MW15, MW30), by substituting mainly SPC, wheat gluten and rapeseed oil. The inclusion levels of BS and MW were determined based on their distinct chemical compositions, specifically their lipid content. As regards the results, HPLC-based high-throughput data on amino acid derivatives revealed the following: carboxymethyllysine was significantly higher in the MW30 feed than in BS5, BS10 and MW15 feeds; carboxyethyllysine was higher in the MW15 and MW30 feeds compared to the others; furosine was lower in the MW15 feed compared to the CO, BS5 and MW30 feeds. Regarding the effect of the insect meals on Atlantic salmon post-smolts, their inclusion had no significant effect on feed conversion ratio, health indicators and the retention efficiency of macronutrients. Apparent digestibility coefficients (ADC) of dry matter, lipid, ash and energy were not significantly different. However, protein digestibility in the 30 % MW group (80.4 %) was significantly lower (P ≤ 0.05) compared to the control and BS5 group (84.5 %). Furthermore, the ADC of protein was found to decrease linearly with increasing levels of insect meals, with MW showing a significant relationship (adjusted r2 = 0.77, p = 0.014). Overall, our study highlights the efficacy of 5 and 10 % BS and 15 % MW as ingredients in the feeds of Atlantic salmon. Other focal points included the undesirable amino acid derivatives and a reduction in protein digestibility associated with 30 % of MW in the diet of Atlantic salmon. Hence, future investigations should focus on the effects of feed processing conditions on the protein quality of mealworm before suggesting higher inclusion levels to the feed industry.

Dehydrated Brewery Residue (DBR) can reduce the cost of rabbit production in Brazil, but affects performance, blood nutrients, and carcass characteristics

The study aimed to determine the chemical composition, apparent digestibility of dry matter, energy, and nutrients of Dehydrated Brewery Residue (DBR) for New Zealand White rabbits, as well as evaluate performance, biochemical and immunological blood parameters, carcass characteristics, and meat quality. Two experiments were carried out: digestibility and performance, both in a completely randomized design. In the digestibility experiment, 20 animals of mixed sexes were used, from 45 to 60 days of age, which consumed reference feed (RF) or test feed (TF - 70% RF + 30% DBR). In the performance experiment, 50 mixed-sex animals were used from 31 to 70 days of age. For digestibility, bromatological analyses were made of total dry matter (DM), crude protein (CP), crude fiber (CF), neutral detergent fiber (NDF), acid detergent fiber (ADF), ether extract (EE), mineral matter (MM), organic matter (OM), calcium (Ca), phosphorus (P), gross energy (GE), hemicellulose, cellulose and lignin from samples of feces, feed (RF and TF) and experimental feed (DBR). In terms of performance, the treatments were the basal feed (BF) + four TF, made up of increasing levels of DBR inclusion (10, 20, 30, and 40%). Overall, the apparent digestibility coefficient (ADC) of DM was 64.68 ±7.91%, while the ADC of GE and CP were 67.39 ±7.79% and 80.64 ±8.99%, respectively, resulting in digestible energy and digestible protein contents of 3,081 ±356 kcal/kg and 17.97 ±2.00%. There was a linear reduction (P&lt;0.05) in the final weight, daily weight gain, and daily feed intake, but there was a linear reduction in production costs (P&lt;0.05) for both the 31- to 50-day phase and the 31- to 70-day phase. Circulating levels of calcium (P=0.013) and phosphorus (P=0.019) responded in a linear decreasing pattern to the experimental feeds. The same response was observed for slaughter weight, hot and cold carcass weight, yield of skin, head, commercial cuts, and relative weight of edible organs, as well as meat quality, in which the loss of water on thawing (P=0.004) and shear force (P=0.005) indicated less juiciness and less tenderness in the meat. Levels of 10 to 40% DBR in feed for rabbits from 31 to 70 days of age mitigate production costs, but result in a worsening of performance and reduce circulating levels of calcium and phosphorus, reduce carcass weight, commercial cuts, and edible organs, as well as increasing water loss on thawing, and reducing meat tenderness.

Amino acid requirements of the infant: the amino acid composition of human breast milk.

The recommended amino acid requirements of the infant are based on the amino acid composition of mature human breast milk. The amino acid composition of breast milk is usually determined following either acid or alkaline (for tryptophan) hydrolysis. For accuracy, however, the known effect of hydrolysis time on amino acid composition should be accounted for. Also, ideally the amino acid composition of breast milk should be given in units of digested (assumed to be absorbed) amino acids. A review of the literature is presented which gives mean total amino acid concentrations in mature human milk (n = 26 studies), mean hydrolysis correction factors (n = 3 studies) and mean true ileal amino acid digestibility coefficients (n = 3 studies, suckling piglet). There were differences between the estimates of amino acid concentration corrected for hydrolysis time and digestibility, and current FAO (2013) recommendations that were not corrected for these factors. The values based on the published literature up until 2023 (mg/g true protein) corrected for hydrolysis time and digestibility gave higher values (more than 16% higher) for leucine, lysine and threonine, and considerably higher values (greater than 30%) for histidine and tryptophan. Current recommendations may need revision.

Influence of Fermented Icacinia manni Meal on Growth Performance, Carcass, Internal Organs and Nutrient Digestibility of Weaner Rabbits

A twelve-week trial was conducted to determine the effect of fermented Icacinia manni meal on the performance, carcass, internal organs and nutrient digestibility coefficient of young growing rabbits. A total of forty (40) growing rabbits were used for the study. Four (4) experimental diets were formulated and labeled (T1, T2, T3 and T4. T1 (the control) had no fermented Icacinia manni meal, while T2, T3 and T4 contained fermented Icacinia manni meal at 5%, 10% and 15%, respectively, partly replacing maize in the diets. The rabbits were divided into four (4) treatments of ten rabbits, and each treatment was allotted to one of the experimental diets using a completely randomized design (CRD). Each treatment was further sub-divided into five replicates of two rabbits each and house individually in double-tier hutches. Feed and water were supplied ad libitum. Data collected were subjected to a one-way analysis of variance (ANOVA). There were no significant (p&gt;0.05) differences in feed intake, growth performance and feed conversion ratio of the growing rabbit. The values for live weight, dressed weight and dressing percentages of the growing rabbits were statistically similar (p&lt;0.05). The internal organs (heart, lungs, liver and kidney) were not significantly affected (p&gt;0.05) by the diets. The nutrient digestibility coefficient of the growing rabbits was influenced by the diet. It was concluded that fermented Icacinia manni meal could be included in rabbit diet up to 15% with no deleterious effects on the animals.

The Effect of Boiled African Pear Seed Meal (Dacryodes edulis) on Growth Performance and Nutrient Digestibility of Weaner Rabbits

This study was carried out to determine the effects of boiled African pear seed meal on the performance and nutrient digestibility coefficient of Weaner rabbits. African pear seeds were washed, chopped into pieces, boiled for one hour, sundried and milled to produce a boiled African pear seed meal (BAPSM). Four diets were formulated and designated T1, T2, T3 and T4. T1 contained maize as the main energy source, and T2, T3, and T4 contained BAPSM at 5, 10 and 15% levels, respectively, replacing maize in the diets. Thirty-two Weaner rabbits aged between 6 – 7 weeks were used for the study. The rabbits were divided into four treatments of eight rabbits, and each treatment was allotted one of the diets in a completely randomized design (CRD). Each group was further divided into four replicates of two rabbits per replicate. The experiment lasted 12 weeks, and the data obtained were statistically analyzed. There were significant differences (p&lt;0.05) in feed intake, final body weight, body weight gain and feed conversion ratio values. All investigated nutrient digestibility coefficient parameters were significantly affected (p&lt;0.05) by the diets. It was concluded that boiled African pear seed meal could be included in Weaner rabbits' diets up to 15% level to enhance the performance and nutrient digestibility coefficient of the animals.

54 Development of an equine metabolism model to describe post-absorptive nutrient dynamics

Abstract Nutrition modelling is instrumental to modern feed formulation and diet optimization across livestock sectors. Mechanistic models of nutrient digestion, absorption, and metabolism are implemented in industry as ‘decision support systems’, and in academia to summarize and examine our cumulative biological knowledge, identify knowledge gaps and test/evaluate hypotheses. However, comparatively less progress in this field has been made in the equine sector. This limits the ability of the equine sector to address complex challenges such as interactions between equine nutrition, management, health, and welfare. To address this gap, a first iteration of a dynamic, deterministic, mechanistic model describing postabsorptive nutrient dynamics for equines has been developed. Model coding and development was performed using Python with specific libraries for mathematical equations and integration. This model was developed primarily based on extant published mechanistic models of protein and energy metabolism in other species. The present model simulates the partitioning of ingested nutrients into digested nutrients, through intermediary metabolism and ultimately to growth and deposition of protein, fat, water, and ash into the body compartments. As shown in Figure 1, the model takes digested nutrients (protein, fat, starch, glucose, volatile fatty acids) as inputs and contains 12 state variables divided into metabolite pools (amino acids, fatty acids, glucose, glycogen, acetyl-CoA, ATP), and body constituent pools (muscle protein, bone protein, hide protein, viscera protein, body fat, body ash). Ingested feed is partitioned into digested nutrients using digestibility coefficients from extant equine literature, and indigestible nutrients are excreted. Meta-analysis was used to develop empirical equations to predict VFA concentrations in the hindgut. VFA absorption is estimated using Michaelis-Menten kinetics including the pH and hindgut volume, assumed as a constant value for a mature horse Acetyl-CoA, a key intermediary metabolism pool, is produced from amino acid, glucose, and fatty acid catabolism and is consumed for maintenance requirements, which is accounted for in an ATP pool. The ATP pool is a ‘zero pool’, which balances the ATP producing and -consuming reactions in the model, with any remaining ATP balance required being pulled from the acetyl-CoA pool. Turnover of protein and fat is represented by differences in accretion and catabolism. Work is ongoing to evaluate the developed model for model performance using data extracted from the literature. The model will be trained and subsequently evaluated using equine studies in three main areas: growth and body composition, protein turnover and nitrogen balance, and energy metabolism. Developing this model for the equine sector will stimulate and assist in defining future research priorities, inform revisions to the nutrient requirements of horses, increase understanding of metabolic processes as well as related disorders, reduce waste via increased focus on precision feeding and support the development of new products and services to improve equine health.