Digestibility Coefficients Research Articles

A comparative study on the effect of limestone particle size on performance, ileal digestibility of calcium and phosphorus, and bone characteristics in broilers and pullets

ABSTRACT 1. The effects of limestone particle size on growth performance, gastrointestinal tract (GIT) traits, ileal morphology, duodenal gene expression of calbindin, apparent ileal digestibility coefficients (AIDC) of calcium (Ca) and phosphorus (P) and tibia characteristics in broilers and pullets were assessed in broilers and pullets. These birds have different growth rates and likely different responses to parameters, such as particle size. 2. A total of 240 chicks aged one day, 120 Ross 308 female broilers, and 120 Hy-Line pullets were allocated randomly into four treatments in a 2 × 2 factorial arrangement with two bird types (broilers vs. pullets) and two limestone particle sizes (<0.5 mm versus 1–2 mm) to give six replicates containing 10 chicks in each from 1 to 21 d of age. 3. Feed intake and weight gain were greater (P < 0.001) and feed per gain (FCR) was better (P < 0.001) in broilers compared to pullets from 1 to 21 d of age. Greater villus width (P < 0.01), villus height (P < 0.001) and crypt depth (P < 0.01) were seen for broilers compared to pullets. 4. Pullets fed coarse Ca particles had higher calbindin gene expression at 21 d of age (P = 0.05). Both AIDC of Ca and P were higher (P < 0.001) in broilers compared to pullets. The AIDC of Ca from 0.463 to 0.516 was increased (P < 0.05) by feeding coarse limestone particles. A significant interaction was found between bird type and limestone particle size (P < 0.01), where pullets fed coarse Ca particles had higher bone P concentration in tibia than broilers. 5. Broilers had better ileum absorptive capacity and growth performance compared to pullets. The AIDC of Ca and P was higher in broilers than in pullets. Increased limestone particle size elevated villus height, AIDC of Ca and concentration of P in the tibia.

Assessment of hydrolysis of partially defatted black soldier fly larvae meal in diets for Nile tilapia Oreochromis niloticus

The chitin content of black soldier fly (Hermetia illucens) larvae meal (BSFM) is known to negatively affect its digestibility by fish. Nile tilapia (Oreochromis niloticus) tolerates well BSFM in the diet. However, chemical hydrolysis of dietary BSFM has not previously been attempted for this species. In this study, based upon a low-fishmeal control diet (40% crude protein and 9% crude fat), three levels of dietary protein, 25%, 50%, and 75%, were replaced by partially defatted BSFM, subjected or not to a prior hydrolysis treatment with formic acid and fed to Nile tilapia juveniles (initial body weight: 0.26 ± 0.00 g). The hydrolysis treatment did not modify greatly the proximate and amino acid composition of the diets, nor did it improve their in vivo apparent digestibility coefficients of dry matter or crude protein. However, it significantly increased the contents of arginine, taurine, and tyrosine, and significantly reduced the contents of methionine, valine, aspartic acid, and glutamic acid in muscle tissue of Nile tilapia. The hydrolysis treatment also decreased fish growth significantly. In contrast, for diets not containing hydrolyzed BSFM, not only did fish fed all three levels of protein replacement grow satisfactorily, but the diets with the levels of replacement of 50% and 75%, with final weights of 23.04 and 23.11 g, respectively, elicited superior fish performance, as compared to the diet with 25% replacement (final weight of 20.09 g). In addition, all three protein replacement diets produced significantly greater growth than the control diet (final weight of 17.72 g). The actual levels of inclusion of BSFM were, respectively, 14.11%, 28.21% and 42.33% of diet, the latter being the highest inclusion level of BSFM reported to date for successful growth of Nile Tilapia.

The effectiveness of coniferous-mineral and zeolite additives in feeding of fi rst-calf heifers under the conditions of Yakutia

The purpose of the work was to study the complex effect of coniferous-mineral and zeolite additives on the milk productivity of first-calf heifers under the conditions of Yakutia. Data have been presented on the study of the influence of a coniferous-mineral additive in combination with a zeolite additive on the milk productivity of fi rst-calf heifers of Simmental breed under the conditions of Yakutia. The scientific and farm experiment was carried out in three groups; the selection and testing of animals was carried out taking into account generally accepted methods in animal science. The use of the complex of feed additives in the rations of the 2nd and 3rd experimental groups of animals made it possible to increase the milk productivity of fi rst-calf heifers by 9,07 and 7,58 % (P &gt; 0,999), respectively. At the end of the experiment, milk yield in the experimental groups was higher compared to the 1st control group by 9,13 and 7,57 % (P &gt; 0,999). In the milk of heifers of the 2nd and 3rd experimental groups, the proportion of fat content increased by 0,12 and 0,08 abs.%, as well as the milk protein content by 0,10 and 0,08 abs.% compared to the 1st control group. The most complete picture of the changes caused by the inclusion of experimental feed additives in the rations of experimental animals can be traced in terms of nutrient digestibility. In fi rst-calf heifers of the 2nd and 3rd experimental groups, the digestibility coeffi cients of nutrients increased as follow dry matter by 2,78 and 2,23 abs.%, organic matter by 3,01 and 1,42 abs.%, crude protein by 3,10 and 1,99 abs.%, crude fat by 3,46 and 2,72 abs.%, crude fi ber by 3,93 and 0,43 abs.%, nitrogen-free extractive substances by 1,52 and 0,52 abs.%, respectively, compared to the 1st control group. Thus, the integrated use of the studied additives in feeding of first-calf heifers improves the digestibility of nutrients and increases their milk productivity under the conditions of Yakutia.

Different starch sources result in distinct responses to diets digestibility, fecal microbiota and fermentative metabolites, and postprandial glycemic response in dogs

The study evaluated the effects of different starch sources on the coefficients of total tract apparent digestibility (CTTAD) of macronutrients, metabolizable energy (ME), intestinal fermentative metabolites, fecal microbiota, and postprandial glycemic response in dogs. Seven diets containing corn, brown rice, sorghum, potato starch, sweet potato flour, chickpea, and pea flour were evaluated. Fourteen adult Beagle dogs were randomly distributed in blocks (periods) and were fed the experimental diets for 15 days during three periods, totaling 6 repetitions. In general, diets with brown rice and pea had higher CTTAD of nutrients, followed by diets containing sorghum, chickpea, and potato. The diet containing sweet potato had the lowest CTTAD of nutrients. Diets containing corn and brown rice presented the highest ME content. Dogs fed the chickpea diet had lower fecal pH, ammonia concentration, and dry matter content (P < 0.05). Generally, higher fecal concentrations of short-chain fatty acids were observed in dogs fed the sweet potato and chickpea diets compared to the potato and brown rice diets (P < 0.05). Pulse-based diets resulted in a higher abundance of Bacteroides plebeius, Prevotella copri, Blautia, and Turicibacter in feces (P < 0.05). A higher abundance of Faecalibacterium prausnitzii and Blautia was observed in the feces of dogs fed the sweet potato diet (P < 0.05). Blood samples collected from dogs fed corn and potato diets indicated a greater increase in glycemic peak concentration and maximum glycemia than the other starch sources (P < 0.05). The period until the glycemic peak was longer for diets containing sorghum and chickpea (P < 0.05). The results obtained in this study showed that sweet potato and pulses improve indicators of gastrointestinal functionality, and help controlling the postprandial glycemic response in dogs.

Growth, not digestibility, in chickens receiving reduced-protein diets is independent of non-specific amino-nitrogen sources when the essential-to-total-nitrogen ratio is constant and lower than 50%

ABSTRACT 1. A 21 d experiment was conducted to investigate whether growth performance and coefficients of amino acids digestibility (cAID) in broilers receiving reduced-protein diets supplemented with different non-essential amino acids (NEAA) were dependent on supplemented NEAA in diets with the same essential-to-total N (eN-to-tN) ratio kept at <50%. 2. The experiment used 240 male broiler chicks, allocated to eight treatments with six replicate pens per treatment, and five chicks per replicate. The diets were either adequate in protein diet (PC), reduced protein (NC) diet or the NC diet supplemented with Gly, Gln, Ser, Ala, Gly + Ser or Ala + Ser. Digesta from the distal half of the ileum were collected on d 21. Tissue samples were collected for analysis for gene expression of protein synthesis and degradation (pectoralis major and liver) and peptide and AA transporters (jejunum). 3. The treatments had no effects on growth performance. Generally, cAID was greater (P < 0.05) in NC compared to the PC diet. Individual supplementation of the NC diet with Gly, Gln, Ser, Ala or Ala+Ser increased (P < 0.01) cAID of Cys compared to the PC diet. There were no treatment effects on mRNA levels for the AA or peptide transporters in the jejunum. Supplementation of the NC diet with Gln, Ser, Ala, or Gly + Ser produced an upward expression (P < 0.05) of S6 kinase in the liver compared to PC and NC. In addition, there was greater (P < 0.05) expression of TRIM36 in the pectoralis major of broiler chickens receiving the NC diet supplemented with Gly. 4. When reduced-protein diets have an eN-to-tN ratio of <50% and the ratio is kept constant in all the diets, growth performance response was independent of the source of non-specific amino-N, but the treatments may influence ileal digestibility of individual AA.

Net energy content of hybrid rye fed to growing pigs and effects of particle size on energy values

An experiment was conducted to determine the digestible energy (DE), metabolizable energy (ME), and net energy (NE) contents of hybrid rye fed to growing pigs using indirect calorimetry and to investigate the effects of particle size on energy values. Thirty growing barrows (18.06 ± 0.83 kg initial body weight) were individually housed in metabolism crates and randomly allotted to one of five dietary treatments to give six replicates per treatment. Two hybrid rye varieties (Bono and Gatano) were ground in a hammermill mounted with a 4.0-mm or 3.2-mm screen to obtain coarse and fine particle size, respectively. Dietary treatments included a corn-soybean meal basal diet and four additional diets containing 300 g/kg of the test ingredients in a 2 × 2 factorial based on hybrid rye variety (Bono or Gatano) and particle size (Coarse or Fine). Pigs were fed experimental diets for 15 days, including 10 days for adaptation and 5 days for total fecal and urine collection to determine the DE and ME of the experimental diets. Pigs were then moved into indirect calorimetry chambers to determine 24-h heat production and 12-h fasting heat production. All data were analyzed using the MIXED procedure of SAS with the individual pig as the experimental unit. The geometric mean diameter (Dgw) for coarsely versus finely ground Bono and Gatano were 1111 versus 594 µm and 1210 versus 717 µm, respectively. The coefficient of apparent total tract digestibility (CATTD) of dry matter (DM) and gross energy (GE) were greater (P < 0.05) in diets containing finely than coarsely ground hybrid rye. The DE and ME of finely ground hybrid rye were greater (P < 0.05) than those of coarsely ground hybrid rye, and the NE of finely ground hybrid rye tended to be greater (P = 0.084) than that of coarsely ground hybrid rye. No differences were observed for the DE, ME, and NE contents between Bono and Gatano. The determined NE for coarsely and finely ground Bono were 11.06 and 11.77 MJ/kg DM, and the respective NE values for coarsely and finely ground Gatano were 11.09 and 11.57 MJ/kg DM. In conclusion, the energy values of different hybrid rye varieties might be comparable. Particle size reduction could significantly improve the DE and ME values of hybrid rye fed to growing pigs, while the NE value was only numerically improved.

High- or low-fibre diet, meal size and frequency: Effect on ileal and total tract digestibility and mean retention time in growing pigs

This study aimed to determine the effect of the size and frequency of meals and diet type (high- or low-fibre) on fibre degradation and retention time of digesta in growing pigs. Pigs (n = 6) were fitted with a T-cannula, and each received all treatments following a 2 × 3 factorial arrangement in a 6 × 6 Latin square experimental design. The diets were either corn-soybean meal-based diet with low fibre (LowFibre) or wheat-barley based diet with high fibre (HighFibre) and distributed differently: 2 meals per day that met 3 times the maintenance energy requirement (2M), the same amount of feed in 8 meals (8M), and 8 meals per day that met 5 times the requirements (8M+). A diet type × meal interaction was observed for mean retention time (MRT) of the solid and liquid phase of digesta where MRT in LowFibre diet was higher in 2M compared to 8M and 8M+ while in HighFibre only 8M had lower MRT than 2M and 8M+ (Solid phase, P = 0.023, Liquid phase, P = 0.097). Ileum digesta from the LowFibre diet was less viscous than ileum digesta from HighFibre diet (P = 0.028) regardless of the meal distribution. Concentrations of the indigestible markers in the ileal digesta (TiO2 and YbCl3) increased faster in the LowFibre compared to the HighFiber diet, and marker concentrations were more constant in the 2M than the 8M and 8M+ treatments (P < 0.05). Coefficient of apparent ileal digestibility (CAID) of dry matter, energy, crude protein, total non-starch polysaccharides (NSP) and insoluble NSP was higher in the HighFibre diet than the LowFibre diet, while opposed results were observed for apparent total tract digestibility (P < 0.05). No effect of meal type was observed on CAID. Blood glucose levels were stable throughout the day for 8M and 8M+ while blood glucose for 2M was decreased between two meals (meal × time effect, P = 0.035). Larger meals in 2M-LowFibre, 2M-HighFibre and 8M+HighFibre can therefore explain longer MRT potentially due to decreased motility and slower gastric emptying. In conclusion, feeding pigs with an increased number of meals per day allows a continuous flow of digesta, stabilized blood glucose and increased digestibility. Ingestion of a high-fibre diet causes increased digesta viscosity. The type of diet had more impact on digestibility and transit time than the meal size and frequency.

Nutrient Digestibility and Blood Composition of Broiler Chickens Fed Diets Containing Biodegraded Sweet Orange (Citrus sinensis) Fruit Peel

Aims: To determine the nutrient digestibility and blood composition of broiler chickens fed biodegraded sweet orange fruit peel-based diets.&#x0D; Study Design: Completely randomized design.&#x0D; Place and Duration of Study: Livestock Research Farm, Federal University of Agriculture Makurdi, Nigeria; fifty-six days&#x0D; Methodology: Sweet orange peels and cattle rumen content were collected. Rumen content was mixed with water at a ratio 1 kg: 1 litre and sieved to get rumen filtrate (RF). RF was mixed with Sweet orange peels at a ratio of 1 litre: 2.5 kg and fermented for 48 hours, sun-dried, milled, and added to broiler diets at different levels: 0% (T1), 5% (T2), 10% (T3), 15% (T4), and 20% (T5). A total of 150 day-old chicks, randomly assigned to five dietary treatments and three replicates per treatment were raised in a 56-day feeding trial. Three chickens of average live body weight similar to the treatment group average were selected and used to determine nutrient digestibility and blood composition.&#x0D; Results: The results showed that the coefficient of digestibility of dry matter, crude protein, crude fibre, ether extract and nitrogen-free-extract did not differ significantly (P &gt; .05) among the treatment groups. Haematological indices; haemoglobin, red blood cell (RBC), packed cell volume, mean corpuscular volume (MCV) and mean corpuscular haemoglobin (MCH), did not differ significantly (P &gt; .05) across the dietary groups, while white blood cell (WBC) and mean corpuscular haemoglobin concentration (MCHC) varied significantly (P &lt; .05). Serum indices; total protein (TP), globulin, glucose, cholesterol, and alkaline phosphatase were significantly affected (P &lt; .05) by the experimental diets, while albumin, aspartate transaminase and alanine transaminase did not differ significantly (P &lt; .05) across the dietary groups.&#x0D; Conclusion: Biodegraded sweet orange peel-based diets can replace maize grains up to 20% without affecting nutrient digestibility or having any adverse effect on blood constituents of broiler chickens.

PSX-2 Data Analytics of a Global Nirs Database of Soybean Meal Nutrient Content

Abstract The nutrient and energy content of soybean meal (SBM) is variable due to genetics, country of origin, agronomic conditions, and to a lesser extent, the solvent-extraction process. The analytical variability among and within-labs can increase the difficulty of detecting differences among sources and establish nutrient interrelationships to estimate some nutrients based on others that are less variable. Near-infrared reflectance spectroscopy (NIRS) can reduce laboratory analytical inconsistencies and increase the sample size for feedstuff evaluation enhancing feed formulation accuracy. The PNE system (Adisseo) has unique NIRS curves based on direct calibrations generated with in vivo data of standard chicken metabolizable energy (AME and AMEn) and amino acid (AA) digestibility methods. This study evaluated the relationship between AA concentrations and crude protein (CP) and among proximate parameters (CP, crude fiber, ether extract, nitrogen-free extract, and ash), AA concentrations, and digestibilities with AME AMEn. The PNE database used contained 77,573 samples of SBM from Argentina (9,684), Brazil (62,322), and the U.S. (5,567) scanned in diverse countries worldwide between 2018 and 2021. Correlation and regression analyses between AA and CP were conducted. The pairwise correlations (P &amp;lt; 0.001) between AA and CP ranged between 0.34 and 0.82. Concentrations of all AAs in SBM can be predicted (P &amp;lt; 0.001) from the positive linear relationships with CP content. However, all coefficients of determination (R2) were low (0.11 to 0.68). The SBM country of origin was a significant factor and interacted with CP (P &amp;lt; 0.001), but R2 improved only slightly when included in these linear models. Multiple linear regression (MLR) and neural networks (NN) analyses were conducted to estimate AME and AMEn based on proximate values, AA concentrations and digestibility, and country of origin. All factors were significant (P &amp;lt; 0.001) in the MLR models for AME (R2 = 0.78, AICc = 643,940.6) and AMEn (R2 = 0.77, AICc = 642,785). Additionally, to have R2 below 0.80, the MLR models had collinearity for digestibility data and branched-chain AAs concentrations. The NN models had a better fit for training and validation datasets for AME (R2 = 0.88, RASE = 39.96) and AMEn (R2 = 0.87, RASE = 37.21). The NN models allowed us to visualize the greater importance of AA digestibility coefficients (His, Val, Trp, Cys, Arg, Leu, Thr) than the concentration of AAs or proximate values to estimate SBM energy values. In conclusion, AA concentrations of SBM cannot be accurately predicted from its CP content. The AA content of SBM varies by country of origin and may vary independently of CP content. The energy value of SBM may depend more on AA digestibility than proximate parameters. Data analytics of NIRS databases with direct calibration of in vivo parameters of energy utilization and AA digestibility elucidates relevant nutritional factors.

PSIX-15 The Effects of Torula Yeast as a Protein Source on Digestibility, Inflammation, and Gut Microbiome in Labrador Retrievers with Chronically Poor Stool Quality

Abstract Four Rivers Kennel examined the effects of varying protein sources on digestibility, inflammation, and gut microbiota in Labrador Retrievers with historically poor stool quality. Thirty dogs (n = 15 males and n= 15 females; ages 3 to 10 years) with stool quality scores ≤ 2.5 on a 5 point scale were randomly assigned to 1 of 3 diets meeting AAFCO requirements with differing protein sources and similar nutrient profiles: 1) chicken meal (PC); 2) 10% brewer’s yeast (BY); and 3) 10% torula yeast (TY; SylPro, Arbiom, Durham, NC). Another 10 dogs (n = 5 males and n = 5 females) with normal stool quality (score ≥ 3) received diet 1 and served as negative control (NC). After 7 days acclimation to diet 1, dogs began treatments. Daily stool scores and weekly body weights were recorded. On days 7, 21, and 36, blood serum was analyzed for C-reactive protein (CRP), and feces for S100A12, alpha-1 proteinase inhibitor (a1PI), calprotectin, and microbiota dysbiosis index (MDI). Apparent total tract digestibility was assessed using the indicator method with 2 g titanium dioxide administered orally via gel capsules. Statistical analysis was performed by repeated measures model in SAS for stool scores, body weight, biomarkers, and microbiota or by one-way ANOVA in JMP for digestibility coefficients. Stool scores were greater in NC (P &amp;lt; 0.01), changed daily in all groups (P &amp;lt; 0.01) without noticeable overall trends, and were not affected by treatment*day interaction (P = 0.64). Body weight was greater (P = 0.01) and CRP less (P &amp;lt; 0.01) in NC dogs than poor stool dogs. Dry matter and carbohydrate digestibility did not differ between groups (P ≥ 0.14). NC dogs had greater fat digestibility compared with BY dogs (94.64 ± 1.33 % vs 91.65 ± 1.25%; P = 0.02). Protein digestibility was reduced in PC (58.91 ± 4.68%) and BY (58.26 ± 4.42%) compared with NC (75.52 ± 5.01 %), but TY diet improved protein digestibility to levels similar to NC (72.18 ± 5.01%, P = 0.03). There were no treatment effects on S100A12 or a1PI (P ≥ 0.44). Calprotectin decreased at a greater rate overtime in TY dogs (P &amp;lt; 0.01). There was a treatment*day interaction for MDI; BY and TY fluctuated less overtime (P = 0.01). Blautia (P = 0.03) and Clostridium hiranonis (P = 0.05) abundances were reduced in BY and TY. Dogs never exhibited significant dysbiosis (MDI &amp;lt; 2), and bacterial abundances remained within normal ranges. Dogs with chronically poor stool quality experience reduced body weights, increased serum CRP, and altered nutrient digestibility, but TY helped improve protein and fat digestibility, sustain microbiome, and reduce fecal calprotectin. Feeding torula yeast long-term may help improve plane of nutrition to better maintain weight and reduce inflammation in dogs with chronically poor stool quality.

PSVIII-18 Standardized Amino Acid Digestibility and Nitrogen-Corrected True Metabolizable Energy of Frozen Raw, Freeze-Dried Raw, Fresh, and Extruded Dog Foods Using Cecectomized and Conventional Rooster Assays

Abstract Processing conditions, particularly temperature and duration of heating, impact the digestibility of pet foods. Various alternative commercial pet food formats are now available, but few have been well tested. Therefore, the objective of this study was to determine the amino acid (AA) digestibility and nitrogen-corrected true metabolizable energy (TMEn) of frozen raw, freeze-dried raw, fresh, and extruded dog foods using the precision-fed cecectomized and conventional rooster assays. The diets tested were Chicken and Barley Recipe [extruded diet; Hill’s Science Diet (EXT)], Chicken and White Rice Recipe [fresh diet; Just Food for Dogs (FRSH], Chicken Formula [raw frozen diet; Primal (FRZN)], Chicken and Sorghum Hybrid Freeze-dried Formula [hybrid freeze-dried raw diet; Primal (HFD)], and Chicken Dinner Patties [raw freeze-dried diet; Stella &amp; Chewy (FD)]. Two precision-fed rooster assays utilizing Single Comb White Leghorn roosters (1.5 to 2.5 yr, 2.5 to 3 kg) were conducted. In the first assay, 20 cecectomized roosters (n = 4/treatment) were used to determine AA digestibility. In the second assay, 20 conventional roosters (n = 4/treatment) were used to determine TMEn. In both assays, roosters were crop intubated with 12 g of test diet and 12 g of corn, and then excreta were collected for 48 h. The reactive lysine:total lysine ratios were 0.94, 0.96, 0.93, 0.93, and 0.95 for the EXT, FRSH, FRZN, HFD, and FD diets, respectively. In general, FD had the greatest AA digestibilities and EXT had the least AA digestibilities. Arginine digestibilities were different (P &amp;lt; 0.05) across all diets and in this pattern: FD &amp;gt; FRZN &amp;gt; FRSH &amp;gt; HFD &amp;gt; EXT. Isoleucine digestibilities were different (P &amp;lt; 0.05) across all diets, but with a slightly different pattern: FD &amp;gt; FRZN &amp;gt; FRSH &amp;gt; EXT &amp;gt; HFD. Lysine digestibility was greater (P &amp;lt; 0.05) in FD and FRZN than EXT, with other diets being intermediate. Methionine digestibility was greater (P &amp;lt; 0.05) in FD than FRSH, with other diets being intermediate. Threonine digestibility was greater (P &amp;lt; 0.05) in FD than EXT, with other diets being intermediate. Valine digestibilities were different (P &amp;lt; 0.05) across all diets and in this pattern: FD &amp;gt; FRZN &amp;gt; EXT &amp;gt; FRSH &amp;gt; HFD. Digestibilities of the other essential AA were not different among diets. TMEn was greater (P &amp;lt; 0.05) in FRZN than FD, FRSH, and EXT, greater (P &amp;lt; 0.05) in HFD than FRSH and EXT, and greater (P &amp;lt; 0.05) in FD than EXT. In conclusion, our results support the notion that diet processing impacts AA digestibility, with freeze-dried raw, frozen raw, and fresh diets consistently having greater digestibility coefficients, as well greater TMEn, than the extruded diet. More research in dogs is necessary to test the effects of these diet formats on palatability, digestibility, stool quality, and other physiologically relevant outcomes.

Evaluation of growth, nutrient absorption, body composition and blood indices under dietary exposure of iron oxide nanoparticles in Common carp (Cyprinus carpio).

The bioavailability, small size and direct absorption in the blood, make nanoparticles (NPs) a remarkable feed additive in the aquaculture industry. Therefore, dietary iron oxide nanoparticles (Fe2 O3 -NPs) were used to examine their effects on growth, nutrient absorption, body composition and blood indices in Cyprinus carpio (Common carp) fingerlings. Healthy C. carpio fingerlings (n = 270) were fed with six canola meal based experimental diets (D1-control, D2, D3, D4, D5, D6) supplemented with 0, 10, 20, 30, 40 and 50 mg/kg Fe2 O3 -NPs respectively. A total of 15 fingerlings (average initial weight 5.51 ± 0.04 g/fish) were kept in triplicates for 70 days. The results indicated that maximum growth performance, apparent digestibility coefficient, body composition and haematological parameters were observed in 40 mg/kg Fe2 O3 -NPs supplementation. All the experimental diets were significantly improved (p < 0.05) in all the above parameters than control diet. In the present research, the recommended dosage of Fe2 O3 -NPs as dietary supplement is 40 mg/kg for improving the growth, nutrient absorption, body composition and haematological indices in C. carpio fingerlings. Hence, this study demonstrates the potential of NPs to improve the health of fish.

Effects of dietary-reduced nitrogen (N) and phosphorus (P) on N and P balance, retention and nutrient digestibility of contemporary fattening pigs fed ad libitum

ABSTRACT The reduction of nitrogen (N) and phosphorus (P) in fattening pigs’ diets is one possible approach to lower N and P excretion in livestock farming relative to N and P intake. Due to the implementation of the European Nitrates Directive and the consecutive amendments to the German fertiliser legislation since 2017, N- and P-reduced diets for fattening pigs are becoming more and more important and are increasingly used in practice. To investigate the effects of such diets on N and P balance and retention as well as on nutrient digestibility of contemporary fattening pigs, a balance experiment was performed with eight barrows (average live weight = 61.5 ± 2.1 kg) which were surgically fitted with a simple T-cannula at the terminal ileum. The pigs received a control diet meeting nutrient requirements (CON) and an N- and P-reduced diet (NPred) ad libitum (n = 4/diet) in a 3-phased feeding regimen (3 weeks/phase). In the last week of each phase, faeces and urine were collected quantitatively for 5 days followed by a 2 × 12 hours collection of ileal digesta. Daily feed intake, live weight gain and feed-to-gain ratio did not differ between CON and NPred. NPred-fed pigs consumed 10.5% (p = 0.006) and excreted 28.3% (p = 0.028) less N than CON-fed pigs. Phosphorus excretion was lowered by 15.1% in NPred-fed pigs (p = 0.012). N and P retention did not differ between CON and NPred, but were elevated in comparison to other studies. N and P efficiency, expressed as nutrient retention divided by nutrient intake, was higher in NPred – than CON-fed pigs (N: 68 vs 60%, P: 54.2 vs 49.3%). Apparent post-ileal digestibility coefficient (DCpost-ileal) and apparent total tract digestibility coefficient (DCtotal) of crude protein were higher in NPred – than CON-fed pigs (p < 0.013), but apparent precaecal digestibility coefficient (DCpc) of crude protein was unaffected by diet. DCpc, DCpost-ileal and DCtotal of P were similar for CON- and NPred-fed pigs. NPred-fed pigs showed an elevated DCpc and DCtotal of organic matter, N-free-extractives and starch compared to CON-fed pigs. DCpc of calcium was also higher in NPred-fed pigs. In conclusion, the results suggest that N- and P-reduced feeding of fattening pigs remains an effective strategy to lower the N and P release into the environment. Furthermore, results indicate that N- and P-reduced feeding leads to a higher N and P efficiency in contemporary fattening pigs.

Xylanase and β-glucanase in tandem improve performance, digestive enzymes activity and digestibility in juvenile Nile tilapia fed corn distillers’ dried grains with solubles-added diet

Recently studies have demonstrated the benefits of xylanase and β-glucanase (XB) in enhancing the digestibility of nutrients in Nile tilapia (Oreochromis niloticus) fed fiber-rich diets. However, the underlying mechanisms of XB on digestive enzymes activity and growth performance are not fully understood. Therefore, this study aimed to determine the effect of XB supplementation on growth performance, blood parameters, activity of digestive enzymes, and apparent digestibility coefficients (ADC) in juvenile Nile tilapia fed corn distillers’ dried grains with solubles (DDGS)-contained diets. A 2 × 2 factorial design was used with two DDGS supplementation levels: one without DDGS (control) and one with 185 g/kg corn DDGS, either unsupplemented (−XB) or supplemented with 0.2 g/kg diet of XB (+XB). Each diet was tested using four replicates of 12 fish each. The fish (n = 192; 7.49 ± 0.07 g) were hand-fed six times daily until apparent satiety over eight weeks. DDGS inclusion improved body weight gain, energy retention efficiency, ADC of crude lipids, and digestive amylase and lipase activity. Fish fed control and DDGS diets with XB had higher feed efficiency ratio (+12.7%), energy retention efficiency (+12.5%), whole-body crude lipids (+6.5%), plasmatic cholesterol (+5.7%), activity of and lipase enzyme (+18.0%), and ADC of crude lipids (+8.8%) than those fed XB-unsupplemented diets. Exogenous XB in DDGS-contained diets increased digestible energy (DE) content by 2.22 MJ/kg, relative to values found in diet with DDGS without XB supplementation. XB improved digestible protein (DP) content by 2.9 g/kg diet relative to value found in the corresponding diets without XB supplementation. Overall, XB supplementation effectively alleviates the adverse effects of NSP in corn DDGS, enhancing digestive enzyme activity, and digestibility of energy and nutrients, thereby improving growth performance of juvenile Nile tilapia. The findings highlight the potential of corn DDGS as a sustainable and nutritive feedstuff for tilapia production.

Effect of Two Pepper Powders (Piper nigrum and Piper guineense) as A Feed Additive in The Ration on Intake and In vivo Digestibility in cavies (Cavia porcellus L.)

Background: Cavies are an essential element in a rural landscape in some African countries as food resources or income sources. Purpose: To study the effects of two peppers (Piper nigrum and Piper guineense) as a feed additive in ration on feed intake and In vivo digestibility of nutrients in cavies in order to improve their productivity. Methods: The experiment consisted of a completely random design of four groups of 5 males and five females per group (40 cavies with weights of 450±50g). The control diet was given to group 1 animals (T0) containing no pepper. The cavies in groups 2 (T1), 3 (T2), and 4 (T3) were fed 0.5% Piper nigrum powder, 0.5% Piper guineense powder, and 0.25% Piper nigrum powder + 0.25% Piper guineense powder, respectively. Similarly, Trypsacum laxum grass was weighed before being served. Results: The study showed that although not significantly (p&gt;0.05), Dry matter (DM), Organic Matter (OM), crude protein (CP), and crude fiber (CF) were higher in animals fed the T0 control ratio compared to the other groups (37.94 g DM/d/animal; 33.71 g DM/d/animal; 5.28 g DM/d/animal and 6.45 g DM/d/animal respectively). In addition, the incorporation of the two peppers (Piper nigrum and Piper guineense) as a feed additive in the ration non-significantly (p&gt;0.05) increased the apparent digestive utilization coefficients (aDUC) of food constituents (DM, OM, CP, and CF) in the cavies. Conclusion: Based on these results, the use of pepper powder in the ration can be considered at an incorporation rate of 0.5% for good feed intake and up to 0.5% for better digestive utilization of nutrients in guinea pigs. The use of a synergy (0.25% of Piper nigrum + 0.25% of Piper guineense) can be considered.

Digestibility of nutrients in the calves' diet depending on the level of selenium and cobalt asparaginate nanoparticles

Due to the uneven distribution of minerals in the soil, the territory of the Russian Federation is divided into biogeochemical provinces. The Saratov region is deficient in cobalt, selenium is at the lower limit of the norm. The article examines the influence of a mineral feed additive consisting of nanoparticles of selenium and cobalt aspartate (OMEK-Co) on the digestibility of proteins, fats, and carbohydrates by calves when drinking milk. The authors established a reliable and positive effect of the studied feed additive on the digestibility and assimilability of nutrients. The increase in digestibility coefficients in calves of the experimental groups is associated with the intake of selenium and cobalt in the body in quantities that provide the required level for growth and development, since all other factors of feeding and housing conditions were the same.

Growth performance, digestive function, thyroid activity, and immunity of growing rabbits fed olive cake with or without Saccharomyces cerevisiae or citric acid

The present study investigated the impact of dietary inclusion of olive cakes (OC) with or without Saccharomyces cerevisiae (SC) and citric acid (CA) on growth, digestive function, thyroid activity, antioxidant status, immunity, and intestinal architecture of growing rabbits. One hundred forty 35-day-old male New Zealand white rabbits were randomly assigned into seven experimental groups with five replicates each, as follows: control (CN), fed the basal diet; OC20 and OC25, fed diets with 20 and 25% OC; OS20 and OS25, fed diets containing 20 and 25% OC with S. cerevisiae at 5 g/kg diet; OA20 and OA25, fed diets supplemented with 20 and 25% OC with 1.0% citric acid. No differences in live body weight, feed intake, feed conversion ratio, and carcass traits were noticed among experimental groups, while body weight gain and carcass (%) were increased (P < 0.05) in OS20 compared to the control. Digestibility coefficients of all nutrients and activities of amylase, cellulose, and trypsin did not differ in treated groups compared to the control except for OS20, which recorded enhancement in nutrient digestibility. Plasma triiodothyronine and thyroxine were elevated (P < 0.05), while triglycerides and cholesterol were reduced (P < 0.05) in OS20 compared to CN. Plasma concentrations of immunoglobulin M and G and superoxide dismutase were increased in treated groups compared to the control. Dietary inclusion of SC and CA improved rabbits’ intestinal health, as the cecal Lactobacillus count was increased, E. coli count was decreased, and villus height was elevated in SC- and CA-treated groups. In conclusion, dietary incorporation of SC or CA enhanced the nutritional value of OC and improved growth performance, nutrient digestibility, thyroid activity, antioxidative status, and gut health of growing rabbits.

Effects of supplementation of α-amylase alone in a model of growing and finishing pigs fed metabolizable energy-reduced diets

Amylase helps break down starches into simpler sugars, which can be absorbed and used for energy by pigs. Two experiments were conducted to assess the effects of α-amylase on apparent total tract digestibility (ATTD) of nutrients and energy, N balance, growth performance, blood metabolites, carcass and meat traits in growing and finishing pigs fed metabolizable energy (ME)-reduced diets. In Exp. I, 36 male pigs (25.9 ± 0.5 kg) were randomly alloted to 1 of 4 dietary treatments: 1) control diet not reduced in ME and no α-amylase (CD), 2) CD + 100 g of α-amylase/t (AM0), 3) CD reduced in 50 kcal ME/kg + 100 g of α-amylase/t (AM-50), 4) CD reduced in 100 kcal ME/kg + 100 g of α-amylase/t (AM-100), with 9 replicates cages. Greater digestibility and metabolizability coefficients, digestible and metabolizable energy were observed in pigs fed α-amylase. In Exp. II, 42 male pigs (25.8 ± 0.2 kg) randomly allotted to 1 of 6 dietary treatments: (1) CD, (2) CD reduced in 50 kcal ME/kg and no α-amylase (CD-50), (3) CD reduced in 100 kcal ME/kg and no α-amylase (CD-100), (4) CD + 100 g of α-amylase/t (AM0), (5) CD reduced in 50 kcal ME/kg + 100 g of α-amylase/t (AM-50), (6) CD reduced in 100 kcal ME/kg + 100 g of α-amylase/t (AM-100), with 7 replicates pens, and divided into: growing I (d 1 to 28), growing II (d 29 to 46), finishing I (d 47 to 70), and finishing II (d 71 to 88). Results were described using orthogonal contrasts, that is, diets without vs with α-amylase (CD vs AM), and ME-reduced diets without vs with α-amylase (CD- vs AM-). Growing I pigs from AM or AM- showed greater feed-to-gain ratio (F:G). A greater F:G was observed in finishing I pigs from CD. Finishing II pigs from CD- showed greater weight gain and average daily feed intake. Growing pigs on AM or AM- showed an increase in digestible protein of diet. A higher digestible dry matter, organic matter, and energy (DE) were observed in finishing pigs from AM, and higher DE was found in pigs from AM-. Pig's meat from CD showed a greater red-green component. Pigs on AM or AM- had greater crude protein in the meat. In conclusion, supplementing α-amylase alone in ME-reduced diets improves ATTD, does not affect performance and promotes minor alterations in other study variables in growing and finishing pigs.

Quality of tifton and alfalfa hays and equine body biometrics

This paper targets the quality of tifton bermudagrass (Cynodon spp.)and alfalfa (Medicago sativa) hays in isoproteic and isoenergetic dietson horse body biometrics. Six equines, between 6.5±0.5 years oldand with an mean body weight of 354±50kg, were used in this study.The treatments consisted of six diets and the experimental delineationwas the Latin square (6x6). The diet’s forage was composed by acombination of hays, in a factorial scheme (2x3), with two forages(tifton bermudagrass and alfalfa) and three types of hay (A, B and C).There was a significant effect in the variables body weight, abdominalgirth, fecal water content, and fecal production for the forage type.Greater digestibility coefficient of dietary dry matter values wereidentified in the diets composed by type A and B alfalfa hay(64.71±2.38% and 63.45±2.41%, respectively), that have significantlysurpassed (P = 0.0061) the results obtained for the type C hay diets. Itwas possible to conclude that the alfalfa hay provided a reduction inthe horse’s body weight and thoracic perimeter, what can be explainedby the greater verified digestibility, as well as the lesser fecal waterretention with the diets containing only the legume.

Effect of citrus peeling (Citrus sinensis) on production performance, humoral immunity, nutrients, and energy utilization of broiler quails

Citrus citrus peeling has a wide range of vitamins and trace minerals that have antioxidant and antimicrobial properties. It is hypothesized that the addition of citrus peeling to broiler quail diets can improve their production performance, humoral immunity, nutrients, and energy utilization. A trial was performed to study the impact of a methanolic extract of citrus peeling (Citrus sinensis) on production performance, humoral immunity, nutrients, and energy utilization of broiler quails. A healthy day-old 300 quails were randomly assigned with 5 replicates each replicate had 15 birds and used CRD for the trial. Different dietary supplementations were presented to different groups. The control group was not supplemented with any supplementation in their feed. While, the 3 other groups were supplemented by 0.5 mL/kg, 1 mL/kg, and 1.5 mL/kg of methanolic extract of dried Citrus sinensis peel (DCSP) in the basal diet (DCSP0.5, DCSP1, and DCSP1.5 groups, respectively). All the birds were allowed ad libitum feeding and water. The feed intake and FCR were significantly higher in the control group, followed by DCSP0.5, and then DCSP1. The significantly lowest feed intake and FCR were observed in the DCSP1.5 group. The weight gain and dressing % were significantly improved with the increasing level of methanolic extract of Citrus sinensis. The significantly highest weights of thymus, spleen, and bursa were recorded in the DCSP1.5 group, followed by the DCSP1. The antibody titers against infectious bursal disease, New Castle disease, and infectious bronchitis disease were significantly higher in the DCSP1.5, DCSP1, and DCSP0.5 groups than in the control group. It was concluded from the study that supplementation of quails with methanolic extract of citrus at a dose rate of 0.5 to 1.5 mL/kg of feed can improve feed intake, weight gain, FCR, dressing percentage, relative weight of lymphoid organs, and digestibility coefficient. Supplementation of Citrus sinensis has also concluded positive impacts on antibody titers against various viral diseases. The best improvement in the evaluated parameters was observed at a dose of extract of citrus was 1.5 mL/kg of feed.