Test Diets Research Articles

Dietary fiber induces a fat preference associated with the gut microbiota.

Eating behavior is essential to human health. However, whether future eating behavior is subjected to the conditioning of preceding dietary composition is unknown. This study aimed to investigate the effect of dietary fiber consumption on subsequent nutrient-specific food preferences between palatable high-fat and high-sugar diets and explore its correlation with the gut microbiota. C57BL/6NJcl male mice were subjected to a 2-week dietary intervention and fed either a control (n = 6) or inulin (n = 6) diet. Afterward, all mice were subjected to a 3-day eating behavioral test to self-select from the simultaneously presented high-fat and high-sugar diets. The test diet feed intakes were recorded, and the mice's fecal samples were analyzed to evaluate the gut microbiota composition. The inulin-conditioned mice exhibited a preference for the high-fat diet over the high-sugar diet, associated with distinct gut microbiota composition profiles between the inulin-conditioned and control mice. The gut microbiota Oscillospiraceae sp., Bacteroides acidifaciens, and Clostridiales sp. positively correlated with a preference for fat. Further studies with fecal microbiota transplantation and eating behavior-related neurotransmitter analyses are warranted to establish the causal role of gut microbiota on host food preferences. Food preferences induced by dietary intervention are a novel observation, and the gut microbiome may be associated with this preference.

A question of digestion: How microalgae species affects lipid and fatty acid digestibility in rainbow trout (Oncorhynchus mykiss)

Alternative nutrient sources for fish feed are currently of high interest. Feed ingredients with suitable lipid contents and valuable amounts of essential fatty acids are especially needed to relieve the usage of fish oil and maintain high product quality of fish from aquaculture. Microalgae contain promising nutrient contents and suitable fatty acid profiles that cover dietary requirements of fish. Nutrient digestibility, however, can be hindered by their rigid cell wall. Therefore, in the presented study, the microalgae species Isochrysis galbana and Tetraselmis chui were processed by freeze-drying and centrifugal milling to evaluate their nutrient and fatty acid digestibility in fish nutrition. For T. chui, an additional treatment with enzyme supplementation was tested. Test diets contained 70% of a fish meal based reference diet and 30% of the respective microalgae meal, as well as titanium dioxide as an inert marker to calculate apparent digestibility coefficients (ADC). Rainbow trout (Oncorhynchus mykiss) were fed for 14 days and faeces were collected via manual stripping. The ADCs of Kjeldahl nitrogen (∼ 64–79%), nitrogen-free extracts (∼ 40–54%) and energy (∼ 52–66%) were not significantly different between the algae species, but I. galbana inclusion resulted in reduced lipid digestibility (∼ 57% to 77%), which was linked to the high content of saturated fatty acids. The fatty acid ADCs were higher for T. chui except for arachidonic acid (20:4 n-6) and lauric acid (12:0). Mechanical or enzyme-treating processing did not increase nutrient and fatty acid digestibility for the microalgae used in this trial, and sole freeze-drying sufficiently ensured nutrient availability. The high digestibility of nutrients and, particularly, polyunsaturated fatty acids of I. galbana and T. chui underscore their potential as fatty acid and nutrient sources in fish feed.

Dried porcine soluble augments dietary fishmeal replacement by poultry by-product meal for large yellow croaker Larimichthys crocea

Two concurrent feeding trials was conducted to assess the effects of replacing fishmeal with poultry by-product meal (PBM) and supplementing dried porcine soluble (DPS) in large yellow croaker Larimichthys crocea diets at the optimal dietary protein level. In trial I, the reference diet (F40) contained fishmeal at 400 g/kg, and 40%, 60% and 80% of the fishmeal was substituted with PBM (the diets were termed as F24, F16 and F8). In trial II, the control diet (F16D0) contained fishmeal at 160 g/kg, and DPS was added at 4, 8, 12 and 16 g/kg in F16D0 (the diets were termed as F16D4, F16D8, F16D12 and F16D16). Fish initially weighing 20.0 ± 0.2 g were fed the test diets for 10 weeks. Fishmeal replacement level significantly influenced final body weight (FBW), weight gain, feed conversion ratio, nitrogen and energy retention efficiencies, ratio of fish-in to fish-out (FIFO), feed cost, activity of superoxide dismutase and catalase in plasma and liver, activity of glutathione peroxidase in plasma, and malondialdehyde content in liver. However, neither fishmeal replacement level nor DPS supplementation level resulted in significant change in condition factor, hepatosomatic index and body composition. There were no significant differences in weight gain and FBW either between F40, F24 and F16 or between F40 and F16D0, F16D4, F16D8, F16D12 and F16D16. The FBW of F16 declined by 3.2% relative to F40, while the FBW of F16D12 increased by 10.1% relative to F16D0. This study reveals that dietary fishmeal level for large yellow croaker could be reduced to 160 g/kg by using PBM as a sole substitute, and DPS supplementation could augment dietary fishmeal replacement by PBM.

Bio-treatment of Cheese Whey by Black Soldier Fly Larvae (Hermetia illucens) reared in Algeria

Whey, a by-product of cheese industry, poses environmental challenges when discharged untreated. This study aimed to mitigate whey pollution and transform it into value-added products using black soldier fly larvae (BSFL). By investigating whey effects on BSFL growth and performance, an innovative waste management strategy was explored. The five-old-day larvae were fed with four diets; dry spent coffee ground (SCG) as the control diet, while SCG wetted with acid, sweet and fermented whey were the test diets. The results showed that whey types increased significantly (p < 0.05) BSFL growth compared to the control, the dry weight (53.83±0.49 Vs 25.10±0.18 mg/larva), growth rate (1.59±0.06 Vs 0.44±0.01 mg/day) and survival rate (78.83±1.25 Vs 68.50±1.5 %) of larvae and reduced their development time (28.00±01 Vs 37.00±01 day). Furthermore, mixing SCG diet with whey enhanced positively their performance by increasing the waste reduction (26.73±0.81 Vs 16.87±0.37 %), waste reduction index (0.85±0.03 Vs 0.45±0.01 %/day), approximate digestibility (36.49±1.52 Vs 20.29±0.53 %) and bioconversion rate (17.94±0.47 Vs11.65±0.52%). Adding whey to SCG diet increased protein content of BSFL (40.11% vs. 34.18%) and reduced fat (36.06 vs. 37.87 %) in dry mass. Whey also improved the composition of frass by increasing the phosphorus and total nitrogen levels. This approach demonstrates a sustainable solution for dairy industries waste, contributing to the circular economy and offering potential applications in animal feed and fertilizer production.

Ileal Digestible and Metabolizable Energy of Corn, Wheat, and Barley in Growing Japanese Quail

This study aimed to determine the ileal digestible energy (IDE), apparent metabolizable energy (AME), and nitrogen-corrected AME (AMEn) of three typical cereals for quail chicks with two age periods (day 15–21 and 22–28). The experimental diets comprised a corn–soybean meal reference diet (RD), and three test diets (TD) that were fed to quail chicks in a completely randomized design with five replicates per diet and 15 birds each. The TD comprised corn, wheat, and barley that partly replaced the RD at 300 g/kg (70% reference diet + 30% test ingredient). Age did not influence the IDE, AME, and AMEn values, while the effect of ingredient type was highly significant on the energy estimates (p < 0.001). The IDE values of corn, wheat, and barley were estimated as 2924, 3440, and 3184 kcal/kg, respectively. The AME values of corn, wheat, and barley were 3519, 2979, and 2710 kcal/kg, respectively. The estimated AMEn values of corn, wheat, and barley were 3255, 2676, and 2281 kcal/kg, respectively. These findings are crucial for optimizing diet formulations to support quail growth and performance effectively, as they provide valuable insights into the energy content of different cereals for quail production. Notably, the high IDE and AME values of wheat suggest its potential as a valuable energy source for quail diets. Understanding these values can aid in formulating diets that meet the energy requirements of quail chicks, leading to improved growth rates, feed efficiency, and overall productivity in quail production systems.

Effectiveness of feeding different biochars on growth, digestibility, body composition, hematology and mineral status of the Nile tilapia, Oreochromis niloticus

Oreochromis niloticus fingerlings (5.15 ± 0.02 g; n = 315) were fed with different types of biochar (BC)-supplemented sunflower meal-based (SFM) diet to investigate the effects of various BC inclusions on their nutritional digestibility, body composition, hematology and mineral status for 60 days. Seven different diets were formulated based on the SFM based diet: one was a control (TD-I, CON) and the other six diets were supplemented with 2% BC derived from different sources. These BCs were derived from the following: cotton stick (CSBC, TD-II), wheat straw (WSBC, TD-III), corn cob (CCBC, TD-IV), house waste (HWBC, TD-V), grass waste (GWBC, TD-VI), and green waste (GwBC, TD-VII) biochar. There were three replicates for each test diet. Each tank had fifteen tilapia fingerlings, and they were fed with 5% of their live wet weight and twice daily. The outcomes showed that the supplementation of CCBC significantly elevated the growth, nutrient absorption, and body composition of the O. niloticus fingerlings (p < 0.05); with concomitant lowering of the quantity of nutrients released into the water bodies whereas HWBC gave negative impacts. The maximal mineral absorption efficiency (Ca, Na, K, Cu, Fe, P, and Zn) was achieved by the supplementation of 2% CCBC. All hematological parameters showed positive improvements (p < 0.05) with CCBC. Interestingly, CCBC significantly improved the growth, digestibility, body composition, hematology, and mineral status of O. niloticus.

Assessment of the Proximate and Mineral Compositions of Moringa Oleifera Leaf Extracts, the Carcass and Eggs of African Clariid Catfish, Heterobranchus bidorsalis

The need to optimize feed efficiency, feed digestibility and improve metabolism, growth, and reproductive performance of fish has necessitated the use of phytogenic feed additives in aquaculture. A Study was carried out to assess the Proximate and mineral compositions of aqueous and ethanolic Moringa oleifera leave extracts (AMOLE and EMOLE respectively) according to standard procedures. Consequently, these two extracts were used to formulate test diets containing 0.00/100g (control), 1.0g/100g, 2.0g/100g and 3.0g/100g inclusion levels. H. bidorsalis samples (n=216; 800.00+150.00g; 37.50±1.5cm) were randomly distributed in triplicate into 24 concrete tanks of size 6m x 4m x1.3m in a completely randomized 2x4 factorial design and fed at 5% body weight twice daily for 16 weeks. The proximate and mineral compositions of the diets was determined while the carcass and the eggs nutrients compositions were subsequently assessed. The proximate composition of the eggs were significantly higher in crude protein contents than the CP in the MOLE (34.14±0.05), AMOLE (38.84±0.17) and EMOLE (38.44±0.07) diets and the Carcass (37.46±0.28) with range (72.32±0.41 (control) - 78.78±0.58 % (3.0/100g)) while the ash (1.44±0.10 (3g/100g - 2.41±0.10% (control)) and ether (2.88±0.09 (3.0/100g) - 3.25±0.9% (control) ) contents where significantly lower than the highest contents of ash (20.01±0.27%) recorded in fish fed 2.0/100g AMOLE diet and (7.94±0.05%) ether recorded in the control diet. Aqueous extraction method had the highest significant (P&lt;0.05) retention of mineral concentrations: Ca (21.04), P (14.89), Mg (16.40), Na (23.33), K (65.57), Fe (10.67), Cu (6.48) and Zn (5.55) compare to ethanolic extraction method: Ca (2.87), P (12.65), Mg (7.65), Na (19.24), K (13.76), Fe (9.07), Cu (2.40) and Zn (2.32). For the carcass, only Manganese, Iron and Copper compositions were significant (P&lt;0.05) among all treatment groups and the control. These findings have far reaching nutritional importance in the healthcare system and will help to address undernutrition in fish broodstock management in a cost effective manner. Thus, the use of M. oleifera leaves extracts as phytogenic feed additives and nutrients booster should be encouraged and sustained towards sustainable aquaculture development.

REPLACING FISH MEAL BY CANOLA MEAL AND SUPPLEMENTING WITH PHYTASE AND CITRIC ACID FOR IMPROVING MINERAL DIGESTIBILITY IN Cirrhinus mrigala FINGERLINGS

The purpose of this study was to analyze how the mineral digestibility of Cirrhinus mrigala was improved by the replacement of canola meal (CM) along with the supplementation of citric acid (CA) and phytase (PHY). A 90-day feeding trial was conducted in a completely randomized design. Sixteen test diets were formulated with different concentrations of CM (0%, 25%, 50%, and 75%), in the basal diet. Each concentration level was supplemented with four doses, one without supplementation, second with 2.5% CA, third with 750 FTUkg-1 PHY and fourth with combined supplementation (CA + PHY) to form sixteen test diets (T1-T16). Fifteen fingerlings (N = 720) were kept in each tank in triplicate. At the end of the trial, it was revealed that as the amount of CM in the diets increased, there was a significant (P≤0.05) increase in mineral digestibility (Fe, Ca, Mg, K, Mn, Cu, P, Na, Cr, Zn and Al). The fish that consumed 50% CM-based diet supplemented with 2.5% CA and 750 FTUkg-1 PHY had the maximum apparent digestibility coefficient of minerals (K 73.76%, Ca 64.79%, Na 62.56%, P 73.11%, Cu 76.52%, Fe 77.14%, Mn 71.87%, Mg 71.42%). The results of this research suggest that supplementing a diet high in CM (50%) with 2.5 percent CA and 750 FTUkg-1 PHY is the most effective strategy to increase the digestibility of minerals in C. mrigala fingerlings. Keywords: Fish meal, substitution, aquaculture, plant meal, acidified phytase

Dietary fat lowers ileal endogenous amino acid losses in broiler chickens

ABSTRACT 1. An experiment was conducted to determine the effect of the source of fat (soybean oil or tallow) on the ileal endogenous amino acid (EAA) losses in broilers. 2. Three nitrogen (N)-free diets; a control diet with no added fat and test diets with 60 g/kg of either soybean oil or tallow were formulated. Titanium dioxide (5 g/kg) was added to all diets as an indigestible marker. Each diet was assigned to six replicate cages (eight birds per cage) from d 18 to 21 post-hatch. On d 21, the digesta were collected from the lower half of the ileum. 3. The endogenous losses of nitrogen and amino acids (AA) were lower (p = 0.08; p = 0.001) in broilers fed diets with soybean oil or tallow, respectively, compared to those fed the diet with no fat. Source of fat had no influence (p > 0.05) on EAA losses. 4. The most abundant AA in the ileal endogenous protein was glutamic acid, followed by aspartic acid, threonine, leucine, serine, valine and proline. In general, the concentrations of AA in the endogenous protein were lower (p < 0.05) with added fat. The exceptions were methionine, cysteine, proline and serine, which were unaffected. The effect of fat source on the AA contents of endogenous protein were inconsistent and differed depending on the AA. 5. The inclusion of fats decreased EAA losses which implied they have beneficial effects beyond direct energy contribution. It can be proposed that the reduction of EAA flow may be an additional mechanism contributing to the extra-caloric effect of dietary fats.

Sleep apnea patients with epiglottic collapse elevate their larynx more with swallowing; videofluoroscopic swallowing study of 80 patients.

The epiglottis plays an integral role in the swallowing mechanism and is also implicated as an obstruction site in obstructive sleep apnea (OSA). The underlying causes of epiglottic collapse during sleep remain unclear. This study aimed to investigate the cognitive functions using the Loewenstein Occupational Therapy Cognitive Assessment (LOTCA) and the neurophysiological and anatomical factors using videofluoroscopic swallowing studies (VFSS). We compared patients with OSA exhibiting epiglottic collapse to those without, assessing differences in anatomical or neurophysiological characteristics. The study included 12 patients with epiglottic collapse (Epi-group) and 68 without (non-Epi group), all undergoing overnight polysomnography (PSG), drug-induced sleep endoscopy (DISE), LOTCA, and VFSS. Oral transit time (OTT), pharyngeal delay time (PDT), and pharyngeal transit time (PTT) were considered as neurophysiological traits, and laryngeal elevation length (LE) as anatomical trait, and were measured across various test diets (10ml of liquid, soft, or solid). The study comprised 80 individuals, 57 men and 23 women, with no significant age, sex, body mass index or PSG parameters between groups, or DISE findings, with the exception of epiglottic collapse. Swallowing metrics from VFSS were normal, with no differences in OTT, PDT, PTT, or LOTCA scores. Notably, patients with epiglottic collapse showed a greater laryngeal elevation when swallowing soft and solid foods (p = 0.025 and p = 0.048, respectively). Patients with epiglottic collapse do not exhibit neurophysiological or cognitive impairments when compared to non-Epi group. However, the Epi-group displayed a significantly increased laryngeal elevation length. This suggests that anatomical factors may have a more substantial role in the development of epiglottic collapse than neurophysiological factors.

Enzyme-treated microalgal co-product diets for rainbow trout aquaculture: Supporting fish growth, phosphorus digestibility, and reducing phosphorus waste emission

Aquaculture is one of the fastest-growing food sectors, producing almost 50% of fish for human consumption worldwide. However, relying on fish meal and oil for aquaculture diets is not sustainable economically or environmentally. Aquaculture feeds also contain terrestrial plant ingredients with indigestible forms of phosphorus (P), of which 70%–80% can be released into aquatic environments. This P influx contributes to eutrophication of freshwater ecosystems that can lead to anoxic conditions. This study explores a more sustainable diet for salmonids, an important and valuable seafood. Our aim was to test ingredients with highly digestible forms of P in nutritionally balanced portions to support fish growth and reduce P loading. We determined the digestibility of three feeds containing raw, extruded, and enzymatically processed microalgal co-product of Nannochloropsis oculata compared to a conventional diet. We also quantified how much P was retained and excreted. We detected highest growth in trout fed enzymatically processed co-product feed, though it was not statistically different (p = 0.846) from growth of fish fed the reference or other co-product diets. The enzyme-treated, microalgal co-product ingredient and diet had comparable values for P digestibility and solid P excretion to the reference diet, but the lowest average solid P excretion of all test diets. Trout fed the enzyme-treated diet had the highest P retention, while the reference diet had the lowest (p = 0.0429). Trout fed the enzyme-treated diet had the lowest (p = 0.0174) and negative dissolved P excretion, while those fed the reference diet had the highest. Results showed that enzyme-treated N. oculata co-product maintains digestibility, increases P retention, and reduces dissolved P excretion compared to the reference diet in rainbow trout. These findings encourage follow-up research to design and test growth performance of diets containing enzyme-treated microalgal co-product as sustainable trout aquafeed.

156 Growth performance, energy, and nutrient digestibility of nursery pigs fed high-shear dry extruded corn and soymeal

Abstract Altering the processing method via high-shear dry extrusion of both soybean meal and corn has been shown to improve diet energy and digestibility. The objective was to evaluate the effect using high-shear dry extruded corn and mechanically processed soymeal on growth performance, energy, and nutrient digestibility of nursery pigs. A total of 240 newly weaned pigs [initial body weight (BW) = 5.7 ± 1.3 kg] were assigned to 1 of 5 dietary treatments (n = 16 pens per treatment with 3 pigs per pen) in a complete randomized design for three dietary phases over a 6 wk study duration. Pigs were allowed a 7-d acclimation period where they were fed a common commercial medicated starter pellet diet (d 0-7, Phase 1). In phase 2 and 3, experimental diets included: 1) solvent-extracted soybean meal and conventional ground corn (Con), 2) solvent-extracted soybean meal and high-shear dry extruded corn (ECorn), 3) mechanically processed soymeal and conventional corn (ExSoy), 4) mechanically processed soymeal and high-shear dry extruded corn (same ME and Lysine as treatment 1 to 3; Comb), and 5) mechanically processed soymeal and conventional corn (energy floated with same Lys:ME; Comb+). The phase 2 mash test diets contained 0.40% titanium dioxide as a digestibility marker (d 8-21) and phase 3 test diets were fed from d 22-42. Pigs were individually weighed on d 0, 7, 21 and 42 and feed disappearance was recorded to calculate average daily feed intake (ADFI) and Gain:Feed within phase 1, 2 and 3, and overall (phase 2 and 3 combined). Data were analyzed using pen as the experimental unit. Compared with Cont, end BW did not differ in the ECorn and ExSoy treatment, while Comb and Comb+ pigs were 13 to 17% lighter (26.1, 24.2, 24.0, 22.6 and 21.5 kg, respectively, P = 0.004). Overall, the Con fed pigs had 30% greater average daily gain (ADG) and 12 to 21% increase in feed efficiency compared with either Comb or Comb+ treatments (P &amp;lt; 0.001). Overall ADFI did not differ. During phase 3, Con and ECorn fed pigs observed increased ADG and feed efficiency compared with pigs fed either Comb treatment (Both P = 0.002, respectively). Compared with Cont, ECorn and Comb+ had greater GE ATTD coefficients, while ExSoy and Comb were less (82.1, 84.6, 86.9, 78.7 and 79.1%, respectively, P &amp;lt; 0.001). Nitrogen ATTD coefficients were greatest in Comb+, followed by ECorn, Cont, ExSoy and Comb (84.4, 78.8, 77.9, 73.0 and 72.3%, respectively, P &amp;lt; 0.001). In conclusion, substituting conventional corn or solvent-extracted soybean meal with extruded corn or mechanically processed soymeal resulted in equal pig growth performance. Further research is needed to determine the effects on the performance of nursery pigs fed diets including more than one high-shear dry extruded ingredients.

PSI-6 Growth performance of weaned pigs fed an activated zinc oxide to replace pharmacological content of dietary zinc oxide

Abstract The objective of this study was to determine the effect of replacing feed-grade zinc oxide (ZnO) with decreased contents of an activated zinc oxide (aZnO) on growth performance of weaned pigs. A total of 720 pigs (Landrace × Yorkshire × Duroc; TOPICS, Richfield, MN) with an initial body weight (BW) of 5.88 ± 0.97 kg were distributed into 60 pens with 12 pigs per pen following a randomized complete block design. After weaning at 18 d of age, pigs were fed one of five diets differing in ZnO source and Zn content during a 3-phase feeding program for 42 d (Table 1). Experimental diets were formulated to meet minimum nutrient requirements. Mortality was monitored daily and analyzed using survival analysis. Performance data were analyzed by multiple linear regression, with BW gain as dependent variable and Zn source (ZnO, aZnO) and Zn content as the independent variables for each phase. Linear regression analysis used diet A as baseline (150 ppm ZnO). In addition, groups receiving diet E and B, both supplemented with the same ZnO level during phase-1, were compared using a t-test. A linear relationship was observed between BW gain and dietary Zn content (P &amp;lt; 0.001) and Zn source (P = 0.026). A slope ratio between the two Zn sources indicated that pigs provided with aZnO had a 72% greater growth rate compared with ZnO. In addition, during Phase 1, when both diets B and E offered similar Zn concentrations (1,200 ppm) as ZnO and aZnO, pigs fed aZnO outperformed ZnO-fed pigs by 490 g (P &amp;lt; 0.001). The mortality was 7.6% less (P = 0.009) for diet C than diet A. No differences were detected among pigs fed the test diets in Phases 1, 2 and 3 for other variables. In conclusion, results show the potential of aZnO as a suitable replacement for ZnO, but also underscore the effect of dietary Zn content on pig performance and mortality. The aZnO source is a suitable replacement for ZnO, enhancing growth performance in weaned pigs and demonstrating potential for reducing overall Zn usage, thereby mitigating the environmental impact of swine production.

Digestibility and nutritional parameters of maize ethanol coproducts and xylanase for broiler diets

ABSTRACT 1. The objective of this study was to determine the nutritional and energy values of four maize distiller’s dried grains with solubles (DDGS) and one maize high protein distiller’s dried grains (HP-DDG) from ethanol production plants in Brazil; to evaluate the digestibility, performance, nitrogen balance and energy values for broiler chickens fed diets containing these coproducts (Experiment I); and to evaluate the effects of xylanase inclusion in diets containing maize DDGS for broilers on energy availability, digestibility, nitrogen balance and gastrointestinal morphometry (Experiment II). 2. For each experiment, 180 broiler chickens aged 17 and 30 days with initial weights of 450 ± 18 g and 1228 ± 33 g, respectively, were used; the chickens were distributed into 36 metabolism cages. The experimental design consisted of complete randomised blocks, with six replications per treatment and five birds per experimental unit. The treatments consisted of a basal diet (BD) and five test diets containing maize ethanol coproducts (Experiment I) one BD and five test diets containing DDGS with inclusions of 0, 8,000, 16,000, 24,000 and 32,000 BXU/kg xylanase (Experiment II). In Experiment I, HP-DDG and DDGS2 presented higher AME and AMEn values (14.1 and 13.9 MJ/kg and 13.4 and 13.3 MJ/kg, respectively), than did the other coproducts (p < 0.05). Compared with DDGS1 and DDGS3, DDGS4 and HP-DDG had higher digestible CP values (p < 0.05). In Experiment II, the inclusion of the enzyme quadratically affected the values of digestible CP and digestible EE (p < 0.05), with the maximum values occurring with the inclusion of 18 750 and 22,170 BXU/kg of xylanase, respectively. 3. The digestible NDF and digestible MM values linearly increased with the inclusion of xylanase (p < 0.05). The addition of xylanase had no effect on gastrointestinal morphometry (p > 0.05). It was concluded that the inclusion of between 18,000 and 22,000 BXU/kg of xylanase resulted in better digestible CP and digestible EE values.

Use of tunicate meal (pleated sea squirt Styela plicata) protein as a partial replacement of menhaden fish meal protein in the diet of juvenile Black Sea Bass

AbstractObjectiveThe pleated sea squirt Styela plicata (subphylum Tunicata), an invasive marine invertebrate in coastal waters of southeastern North Carolina, was investigated as an alternative protein source to fish meal (FM) in the diet of juvenile Black Sea Bass Centropristis striata.MethodsSix different isoproteic and isolipidic diets were formulated to replace 0.0, 8.3, 16.7, 25.0, 33.3, and 41.6% of FM protein with tunicate meal (TM) protein by supplementing 0, 5, 10, 15, 20, and 25% TM in the diets. The experimental system consisted of eighteen 75‐L tanks supported by a recirculating seawater system in an indoor, climate‐controlled laboratory. Juveniles (average weight = 7.1 g) were stocked at a density of 15 fish/tank (N = 3 tanks/treatment) and were fed the test diets daily to apparent satiation for 55 days.ResultReplacement of FM protein with TM protein caused slight declines in dietary amino acid concentrations (notably arginine, methionine, and tryptophan) at higher replacement levels. At terminal sampling, no significant differences in survival (87–96%), percent body weight gain (157–228%), feed conversion ratio (1.50–1.71), or proximate composition were observed among dietary treatment groups. However, significant positive linear trends were found between incremental levels of TM and final fish weight, body weight gain, and specific growth rate. Whole‐body fatty acid composition reflected dietary levels.ConclusionResults indicate that TM protein can be used to replace at least 41.6% of the FM protein in the diet for juvenile Black Sea Bass without adverse effects on survival, growth, feed utilization, or whole‐body proximate composition.

Gas-liquid chromatography analysis of phospholipids and triglycerides in Plodia interpunctella (Hübner) larvae: Effect of different diets

The Indian meal moth, Plodia interpunctella (Hübner) (Lepidoptera: Pyralidae) is an important insect pest on a wide range of stored food diets. This study employed gas-liquid chromatography to investigate the influence of different diets (pistachio, raisins, and walnuts) on the composition of phospholipids and triglycerides in fifth instar larvae of P. interpunctella. The fatty acid profiles of the larvae revealed seven essential fatty acids including myristic, palmitic, palmitoleic, stearic, oleic, linoleic, and linolenic acids. The fatty acid composition of larvae-extracted phospholipids and triglycerides also varied according to the diet type. In terms of phospholipids, the highest concentration of myristic acid was observed in larvae fed walnut. Raisins exhibited the highest levels of palmitoleic and oleic acid, while pistachio demonstrated the highest concentration of linoleic acid. However, no significant differences were observed among the treatments concerning palmitic acid, stearic acid, and linolenic acid. Regarding triglycerides, no significant differences were found among the treatments in terms of myrisitc acid and oleic acid. However, the raisins treatment displayed the highest amount of palmitoleic acid, while both pistachio and walnut treatments exhibited the highest levels of linoleic acid. Additionally, the concentration of linolenic acid in larvae fed walnut was higher than other test diets. These findings provide valuable insights into the fatty acid composition of P. interpunctella fed different diets. Such knowledge can be utilized in developing pest management strategies, as the manipulation of fatty acid profiles in insects’ diet could potentially impact their growth, development, and fitness.

Standardized ileal digestibility of amino acids in Chinese fermented soybean meal from different sources fed to mid and late-gestating sows.

We determined apparent ileal digestibility (AID) and standardized ileal digestibility (SID) values of crude protein (CP) and amino acids (AA) in fermented soybean meal from five different sources (FSBM 1 to 5) in China when fed to mid and late-gestating sows. Twenty-four parity four sows (12 at 30 d in gestation and 12 at 80 d in gestation) were fitted with a T-cannula in the distal ileum and used in this experiment. Sows were randomly assigned to a replicated 6 × 3 Youden square design including six diets and three periods. Six diets were provided for sows in mid and late gestation, including a nitrogen-free diet and five test diets containing 26% FSBM from different sources. Results showed that there were differences in AID and SID of CP among the different FSBM samples, but no differences between sow physiological stages were observed. Specifically, when mid-gestating sows were fed FSBM 2, the AID of CP was the lowest, whereas FSBM 3 exhibited a greater AID of CP when compared to the other FSBM samples (P < 0.01). Furthermore, during late gestation, FSBM 3 consistently had greater SID of CP when compared to other FSBM samples (P < 0.01). The ileal digestibility of most AA varied with different FSBM samples. In both mid and late gestation, differences (P < 0.05) were observed for AID of lysine, tryptophan, histidine, and arginine across different FSBM samples. Similarly, the AID of dispensable AA (cysteine, glutamine, and serine) also exhibited differences (P < 0.05) across different FSBM samples in both mid and late-gestating sows. For mid-gestating sows, SID differences relating to lysine, phenylalanine, tryptophan, threonine, and arginine were observed among different diets (P < 0.05). In late-gestating sows, SID values for lysine, tryptophan, leucine, and arginine differed across diets (P < 0.05). Furthermore, the ileal digestibility of some dispensable AA was influenced by physiological stage, as evidenced by greater AID and SID values for glycine, glutamine, cysteine, and serine in late-gestating sows when compared to mid-gestating sows (P < 0.01). In summary, our study determined AA ileal digestibility of different FSBM fed to mid and late-gestating sows. We observed that the AA ileal digestibility differed among five FSBM samples, but the physiological stage of sows did not affect the ileal digestibility of CP and most AA. Additionally, when formulating diets for sows, it is crucial to consider the nutritional value differences of FSBM.

Broiler Age Differently Affects Apparent Metabolizable Energy and Net Energy of Expanded Soybean Meal.

Accurately determining the energy values of ingredients is crucial for meeting energy requirements and achieving maximum production performance of animals. This study was conducted to measure the available energy values of three expanded soybean meals (ESBMs) for Arbor Acres male broilers from 14 to 16 day and 28 to 30 day using the difference method. A corn-soybean basal diet was formulated, and test diets were developed with 25% ESBMs as substitutes for energy-yielding ingredients. A completely randomized design was used for determining heat production and energy balance of broilers in 12 open-circuit respiration chambers, with six replicates per group. Prior to measurement, four (14 to 16 day) or two (28 to 30 day) birds per chamber were given a 4-day adaption to diets and chambers. The period lasted for 3 days to determine the apparent metabolizable energy (AME), nitrogen balance, gas exchanges, and heat production. Broilers fed test diets with 25% ESBM exhibited higher nitrogen intake (p < 0.05), nitrogen excreta (p < 0.05), and increased energy deposition as protein irrespective of age (p < 0.05). Furthermore, results showed that AME, nitrogen corrected AME (AMEn), and net energy (NE) values of 3 ESBMs averaged 10.48, 8.93, and 6.88 MJ/kg for broilers from 14 to 16 day, while averaged 11.91, 10.42, and 6.43 MJ/kg for broilers from 28 to 30 day. Broilers from 28 to 30 day showed significantly higher AMEn values but lower NE/AME values of ESBMs compared with those from 14 to 16 day (p < 0.05). Therefore, age-dependent energy values of a single ingredient should be considered in feed formulations to optimize economic returns.

Type of black soldier fly (Hermetia illucens) larvae frass influences the nutritional value when included in a prepared diet for Mozambique tilapia (Oreochromis mossambicus)

Black soldier fly (Hermetia illucens) larvae (BSFL) farming is expected to increase, and a by-product is the ‘frass’. The dietary inclusion of BSFL frass has been shown to enhance tilapia and catfish growth/immunity. However, the composition of BSFL frass, and potentially their nutritive value to fish, may depend on the initial provided substrate. In this 8-week nutrition trial, BSFL frass made from either expired fish diet (EFD; 45% crude protein) or a combination of fruits/vegetable peels (FV; 9.3% crude protein) were included in the diets of Mozambique tilapia (Oreochromis mozambicus) at 5% or 10%. The EFD and FV frass had a different nitrogen, mineral, and amino acid profile, and this information was used to formulate the diets. Results showed that EFD frass at 10% significantly (P < 0.05) enhanced tilapia growth compared to fish fed the control diet, but performance of fish fed the other test diets were not different (P > 0.05) from the control. There was no significant difference in the crude protein or lipid content of tilapia, but some differences were observed in the amino acid and fatty acid composition. Among the test minerals, only phosphorus was significantly affected, which was higher in tilapia fed the FV frass diets. Liver histology showed some minor inflammation and blood vessel congestion in tilapia fed the 10% frass diets, while the intestinal histology had a better cumulative score among all the frass diets compared to the control. Results indicate that the initial substrate provided to the BSFL can influence the nutritive value of the frass to fish.

Gamma ray irradiation enhances defatted Hermetia illucens larvae meal as a dietary alternative to fishmeal for Acanthopagrus schlegelii juveniles

The current research investigated whether gamma (γ)-irradiation could improve the viability of defatted Hermetia illucens larvae (HIL) meal as a fishmeal alternative in black sea bream (Acanthopagrus schlegelii) diets. Three diets were formulated with equal protein (420 g/kg) and lipid (80 g/kg) contents. A diet containing 400 g/kg fishmeal was served as the control diet (C), and 50% of fishmeal in diet C was replaced by either defatted HIL meal or γ-irradiated defatted HIL meal to produce diet HR and diet HR10, respectively. Fish fed diet HR exhibited lower final body weight and weight gain compared to those fed diet C, while no statistically significant differences were found between fish fed diets C and HR10. Additionally, fish fed diet HR10 exhibited significantly lower feed intake, feed conversion rate, nitrogen waste, hepatic malondialdehyde content, relative usage of fishmeal and fish oil, fish-in to fish-out ratio, and economic conversion ratio, and meanwhile significantly higher nitrogen retention efficiency, hepatic total antioxidant capacity, economic profitability index and profitability, than those fed diet C. Fish fed different test diets showed statistically equal alpha diversity of intestinal microbiota, whereas the beta diversity of intestinal microbiota in group HR was far from groups C and HR10. Compared to fish fed diet C, the gut microbiota composition of fish fed diet HR showed significant alterations at both the phylum and genus levels. However, the altered composition of intestinal bacteria was partially restored in fish fed diet HR10. The above findings indicate that treating defatted HIL meal with γ-ray can reduce dietary fishmeal content for black sea bream to 200 g/kg without any adverse effects on growth, proximate composition and intestinal microbial diversity, and meanwhile ameliorates the feed utilization, hepatic antioxidant capacity, and intestinal microbiological composition of black sea bream. Furthermore, feeding γ-irradiated defatted HIL meal enhances the economic profitability, while reduces the waste output and reliance on fishery resource of black sea bream aquaculture.