Dry Matter Digestibility Coefficients Research Articles

Nutrient digestibility of diets containing five different insect meals in gilthead sea bream (Sparus aurata) and European sea bass (Dicentrarchus labrax)

In the recent years, insect meals have been studied as alternative feed ingredients for aquafeeds, due to their adequate nutrient composition and low ecological footprint. These studies involve nutrient digestibility measurements, as they provide valuable information on the ability of fish to utilize insect meal efficiently. In this context, the current study evaluated the nutrient digestibility in European sea bass (Dicentrarchus labrax) and gilthead sea bream (Sparus aurata) fed diets with five different insect meals. For this investigation, diets including 19.5 % of each insect meal from yellow mealworm (Tenebrio molitor – TM), black soldier fly (Hermetia illucens – HI), common housefly (Musca domestica – MD), super worm (Zophobas morio – ZM) or lesser mealworm (Alphitobius diaperinus – AD) and a control fish meal (FM) diet were tested. In European sea bass, TM and MD diets showed similar dry matter, protein, fat, energy, and organic matter ADCs among each other as well as with the FM diet (P > 0.05). However, adjusted protein ADC of TM and ZM diets (93.4 – 93.6 %) were significantly higher (P < 0.05) compared to the FM diet (91.9 %). Fat ADC was similar in all dietary groups (88.6–92.4 %; P > 0.05). The HI diet exhibited significantly lower dry matter, protein and organic matter ADCs compared to the FM diet (P < 0.05). Moreover, the AD diet presented significantly lower digestibility coefficients of dry matter, organic matter and energy than the FM diet (P < 0.05). The dietary contents of crude fiber and ash, and the inclusion of plant feedstuffs correlated negatively with various ADCs (P < 0.05). Regarding gilthead sea bream, the ADCs of dry matter, organic matter, protein, adjusted protein and energy were not affected by the different dietary treatments (P > 0.05). Fat ADC of the TM diet (73.6 %) was significantly lower compared to the other five diets (78.9–84.3 %; P < 0.05). The individual amino acid ADCs values were found to be very high in all experimental diets (90.9 – 98.0 % for European sea bass and 88.9 – 97.2 % for gilthead sea bream). In sea bass, the variation in crude protein and adjusted protein ADCs was strongly reflected on the individual amino acid ADCs. Nevertheless, the “true protein digestibility” as expressed by the sum of amino acids was not affected by the insect inclusion compared to the FM diet (P > 0.05), while a significant difference was observed between the ZM and HI diets (95.9 % and 94.1 % respectively; P < 0.05). In sea bream, the sum of amino acids and the individual amino acid ADC values did not differ among the experimental diets (P > 0.05) except for methionine (P < 0.05). Conclusively, in sea bream all diets exhibited similar overall digestibility. In sea bass, compared to the FM diet, TM and MD diets had similar or even slightly better digestibility, whilst diets HI and AD presented lower overall digestibility.

Cassava residues in the diet of slow-growing broilers

ABSTRACT Cassava by-products are abundant and largely unused in familiy agro-industries in the Amazon region, where slow-growing broilers are commonly raised. Thus the incorporation of cassava by-products in broiler feed may provide starch enrichment for better zootechnical performance. We evaluated the use of cassava residues instead of corn in the diet of slow-growing broilers. We determined the chemical composition of cassava scrapings (CS) and cassava starch residue (CSR), and tested the digestibility of the residues in 192 broilers and three treatments: inclusion of 30 g kg-1 CS or CSR and a control without residue, with eight replicates of eight broilers each. Digestibility was assessed through collection of total excreta from 19 to 22 days of age. Apparent and corrected metabolizable energy, and apparent digestibility coefficients of dry matter, crude protein and crude energy were significantly higher for CSR than CS. Therefore, only CSR was used in a performance experiment using 324 broilers 30 to 90 days old, distributed in four treatments (0; 6.8; 13.4 and 20 g kg-1 CSR in feed) with nine replicates of nine broilers each. There was no significant difference among treatments in weight gain, feed intake, yield of carcass, breast and viscera, meat color, luminosity, pH, shear force, cooking-weight loss and drip loss. As there was a significant reduction in feed conversion and thigh and drumstick yield for 20 g kg-1, we suggest the incorporation of CSR up to 13.4 g kg-1.

Nutrient utilization of native herbage and oat forage as feed for Tibetan sheep (Ovis aries)

AbstractSatisfying the animals feed demand from the forage supply by grasslands remains a major challenge in the grassland–livestock ecosystem. To provide an alternative forage sources, this study conducted two feeding trials in the summer of 2015 and 2016 to compare the nutritive value, digestibility and nutrients utilization of native pasture (NH) and oat forage (OT) fed to Tibetan sheep (Ovis aries). Twelve Tibetan sheep with a mean body weight of 39.11 ± 3.66 kg in 2015 and 27.97 ± 2.69 kg in 2016 were use in this study. The experiment was 2 (year: 2015 and 2016) by 2 (forage: NH and OT) factorial. Data on proximate analysis, fiber fraction and nutrients digestibility were collected and analyzed using general linear model. However, the crude protein (CP) and water‐soluble carbohydrates contents in OT were higher (P &lt; .001) than those in NH by 7.81–8.93% and 46.40–47.05%, respectively. In contrast, the neutral detergent fiber (NDF) and acid detergent fiber contents were higher (P &lt; .001) in NH by 14.28–15.78% and 15.62–18.00%, respectively. The dry matter digestibility coefficient in OT (0.82 in 2015 and 0.79 in 2016) was significantly higher than that in NH (0.68 in both years). In addition, the OT diet had higher (P &lt; .001) organic matter, NDF and CP digestibilities. Animals fed OT retained significantly more nitrogen (2.66 g/day in 2015 and 1.93 g/day in 2016) than those fed NH (0.96 g/day in 2015 and 0.42 g/day in 2016). The digestible energy and metabolizable energy were higher (P &lt; .001) in OT than in NH. Our data indicated that Tibetan sheep urinary N excretion increased by 0.726 g with increase of 1 g in the nitrogen intake. Conclusively, the OT had higher nutritive value than NH and could therefore use to satisfy livestock demand and reduce the grazing pressure on grasslands.

Effect of dietary inorganic and organic chromium on nutrient utilization and growth performance in Black Bengal goats (Capra hircus)

An experiment was conducted to investigate the effect of dietary chromium (Cr) supplementation on nutrient utilization and growth performance in Black Bengal goats. Thirty Black Bengal kids of 3–5 months (5.40 ± 0.34 kg body weight) were assigned randomly to five groups. The experimental diets consisted of a basal diet supplemented with Cr at the rate of 0 (basal diet without any supplementation), 1.0 and 1.5 mg/kg (inorganic Cr), and 1.0 and 1.5 mg/kg (organic Cr). The duration of the growth experiment was 150 d, followed by a 7-d digestibility trial. Results showed that the total dry matter and crude protein intake of Cr supplemented groups were comparable with the control group (P = 1.00). However, the nutrient utilization in the 1.5 mg/kg inorganic Cr and 1.5 mg/kg organic Cr groups were better, with a higher digestibility coefficient for dry matter, crude protein, ether extract, organic matter, total carbohydrate, and hemicellulose (P < 0.05) when compared with the remaining groups. The average daily gain of 1.5 mg/kg organic Cr supplemented groups were significantly higher than the rest of the groups (P = 0.039). Cr supplementation tended to improve the feed conversion ratio per dry matter intake (P = 0.09) and crude protein intake (P = 0.023) in all the treatment groups. In conclusion, dietary supplementation of 1.5 mg/kg organic Cr may positively influence the nutrient utilization and body weight gain of Black Bengal goats.

Evaluation of extruded full-fat soybean as the substitution for fish meal in diets for juvenile Scophthalmus maximus based on growth performance, intestinal microbiota, and aquaculture water quality

Extrusion technology is applied to improve the utilization of soy products, providing an alternative to fish meal (FM) as a component of feed. In this study, a 60-day feeding of turbot (Scophthalmus maximus) was conducted to evaluate the effects of the partial substitution of FM with extruded full-fat soybean (EFS) on growth performance, digestion capacities, intestinal microbiota, and aquaculture water quality. Four isonitrogenous (427.95 ± 0.38 g/kg crude protein) and isolipidic (9.80 ± 1.13 g/kg crude lipid) diets were formulated to contain FM with EFS substitution of 0% (EFS 0%), 10% (EFS 10%), 20% (EFS 20%), and 30% (EFS 30%). Each diet was fed twice a day in triplicate to juvenile turbot (initial body weight, 5.35 ± 0.07 g). The results showed that the turbot fed with EFS 30% had significantly lower body weight, specific growth rate, and protein efficiency ratio than turbot with other diets. In addition, the EFS 30% significantly decreased total serum cholesterol, low-density lipoprotein contents, intestinal folds height, and apparent digestibility coefficients of dry matter and crude protein. It also increased pathogenic Cyanobacteria at the phylum level, decreased probiotics, Rhodobacterales, and Pseudomonadales at the order level, and decreased leuconostoc and Psychrobacter at the genus level. Compared with other treatments, the EFS 30% displayed the lowest proportion of nitrogen for growth and the highest fecal nitrogen loss. Furthermore, the water quality indicators such as ammonia nitrogen discharge, total suspended solids, and fine solid accumulation (< 15 μm) reached the peak in the EFS 30% group. In conclusion, EFS is a feasible turbot feed that can substitute up to 20% of FM with no adverse effects on growth performance, digestive function, intestinal microbiota, and aquaculture water quality.

Effect of dietary soybean meal on growth performance, apparent digestibility, intestinal digestive enzyme activity and muscle growth-related gene expression of Litopenaeus vannamei

Soybean meal is one of the major components of aquatic animal diets, whereas little information is available about the evaluation of soybean meal growth suppression mode of action. A 42-day feeding trial was performed to assess the effects of dietary soybean meal on growth performance, apparent digestibility, intestinal digestive enzyme activity, and muscle growth–related gene expression of Litopenaeus vannamei. A total of 600 shrimp were randomly distributed into 20 tanks with 30 shrimp per tank and four tanks per group. The soybean meal was added to the diets at the rate of 20% (T20), 28% (T28), 35% (T35), 42% (T42), and 50% (T50), respectively. Shrimp were fed with apparent satiation three times daily. Results indicated that the final body weight, weight gain rate, specific growth rate, feed intake, intestinesomatic index, dressed weight percentage, and the apparent digestibility coefficients of dry matter, crude protein, crude lipid, and ash were linearly decreased (p &amp;lt; 0.05), but feed coefficient was linearly increased (p &amp;lt; 0.05) as dietary soybean meal increased from 20% to 50%. The intestinal trypsin and amylase activities were decreased (p &amp;lt; 0.05) as dietary soybean meal increased from 20% to 50%, and reached significance at the level of 35%, 42%, and 50%. Shrimp fed with T20 had higher (p &amp;lt; 0.05) intestinal lipase activity than those fed with other diets. The mRNA relative expression of growth hormone, myogenic regulatory factor 5, and target of rapamycin was downregulated (p &amp;lt; 0.05) as dietary soybean meal increased from 20% to 50%. To conclude, dietary soybean meal exceeded 28% significantly inhibited growth performance of L. vannamei, mainly due to the negative impact of soybean meal on digestion and feed utilization and also the inhibition on the muscle growth and related gene expressions.

Innovative swine blood hydrolysates as promising ingredients for European seabass diets: Impact on growth performance and resistance to Tenacibaculum maritimum infection

Hydrolysates from high-protein coproducts are rich in bioactive peptides (small amino acid chains with properties beyond their nutritional value). When included in aquafeeds, they may promote fish robustness while increasing animal blood value and minimizing waste, contributing to a circular economy. This work assessed how innovatively produced blood hydrolysates (BH) included in plant-based diets for European seabass (Dicentrarchus labrax) affected growth performance and resistance to Tenacibaculum maritimum infection. Three fractions of swine BH obtained by autohydrolysis (AH) or enzymatically were selected. AH fraction was oven-dried, whilst the enzymatically obtained BH were further submitted to a micro (RMF) and nanofiltration (RNF) and the respective retentates freeze-dried. A commercially based diet was formulated, where 50% of fishmeal was replaced by vegetable proteins, and used as negative control (NC). Each BH fraction was then added at 3% to the NC and further compared to a fishmeal-based diet (positive control, PC); all diets remained isolipidic and isoproteic. Diets were assigned to triplicate groups of European seabass juveniles (12.3 ± 1.4 g) and fed three times daily until apparent satiation in a recirculating saltwater system. After a 12-week growth trial, fish were bath challenged with T. maritimum and cumulative mortality followed for 8 days. A digestibility trial was also performed in parallel. Hydrolysates-containing diets had a significantly lower apparent digestibility coefficient (ADC) of dry matter compared to the PC, but RNF did not differ from the NC. RMF and AH had lower lipid ADCs than both controls, while the RNF only differed from the PC. Mineral ADCs of PC, NC and RNF were similar. Calcium ADC in RMF and AH was significantly lower than all other diets; RMF also displayed lower copper and potassium ADCs. Fish fed PC had the highest final weight, followed by NC and RNF. Daily growth index and feed conversion ratio (FCR) of RNF was similar to both controls. RMF induced the lowest final weight, highest FCR and reduced villus length in anterior intestine. This diet has also resulted in increased plasmatic peroxidase, but lower lysozyme, compared to all other treatments, showing the lowest disease resistance. Results clearly show that the RNF was the only test diet that significantly reduced European seabass mortality after T. maritimum infection, without affecting fish growth in relation to a practical plant-protein based diet, highlighting its high potential for aquafeeds supplementation.

A Natural Gas Fermentation Bacterial Meal (FeedKind®) as a Functional Alternative Ingredient for Fishmeal in Diet of Largemouth Bass, Micropterus salmoides.

A 10-week growth study was conducted to evaluate the effect of a natural gas fermentation bacterial meal (FeedKind®, FK) as a fishmeal (FM) alternative in largemouth bass (Micropterus salmoides) (48.0 ± 0.03 g). Four isonitrogenous and isoenergetic diets were formulated including one commercial control (C, 42% FM) and three experimental diets with gradient FK of 3% (FK3, 29%FM), 6% (FK6, 26%FM) and 9% (FK9, 23%FM), respectively. FK-fed groups showed significantly higher SR than that of C group. The WGR and SGR of fish fed FK3 and FK6 were significantly higher than those of FK9, but not statistical different from the C group. FK-fed groups showed higher apparent digestibility coefficients of dry matter and nutrients. Further, FK-fed groups increased the ratio of SOD/MDA in the plasma and liver, and the upregulation of intestinal Keap1 and downregulation of HIF1α was found in FK3. Furthermore, FK-fed groups showed higher microbial richness and diversity. Pearson correlation analysis found that antioxidant relevant biomarkers were negatively correlated with the relative abundance of certain potential beneficial bacteria. In conclusion, supplemented up to 3–6% FK replacing FM in a low FM diet of largemouth bass could increase growth, survival rate, antioxidant capacity, and improve gut microbiota.

Effect of processed sweet lupin (Lupinus angustifolius) grain supplementation on growth performance and socioeconomic feasibility of Doyogena sheep in Ethiopia.

BackgroundThe experiment evaluated the effect of supplementing sheep fed natural pasture hay withprocessed sweet lupin grain on growth performance and its economic feasibility. The finding revealed that use of steamed lupin shown to improve the nutritivevalue of the grain and sheep performance.MethodsThe experiment was carried out using 24 yearling lambs with initial body weight of 27.53 ± 2.67 kg (mean ± SD) for 126 days (21 days quarantine, 15 days of adaptation and 90 days growth trial followed by 7 days digestibility trial). The experiment was laid out in a randomised complete block design consisting of four treatments and six blocks. Treatments comprised the feeding of natural pasture hay ad libitum + concentrate mix 440 g (T1), natural pasture hay + 440 g/day roasted, coarsely ground sweet lupin grain (T2), natural pasture hay + 440 g/day sweet lupin grain soaked in water for 72 h (T3), natural pasture hay + 440 g/day steamed sweet lupin grain (T4).ResultsThere was improvements in total dry matter intake and digestibility coefficients of dry matter, organic matter, crude protein, neutral detergent fibre and acid detergent fibre in sheep supplemented with processed sweet lupin grains compared (T4) by 58.49%, 24.66%, 39.39%, 22.97% and 39.68%, respectively, over the control group. Specifically sheep supplemented with T4 had significantly higher (p < 0.001) average daily gain (by 51.04%), feed conversion efficiency (46.34%) and daily weight gain (144.78 g/day) compared to the control treatment, respectively. All processing methods resulted in favourable average daily gain and net return, thus can be employed in feeding systems depending on their availability and relative cost.ConclusionsSupplementing sheep fed natural pasture hay with 440 g/day steamed sweet lupin grains improved growth performance and fattening economics of Doyogena sheep compared to T2 (roasted sweet lupin grain), T3 (soaked sweet lupin grain) or the control (T1).

Effects of exogenous xylanase supplementation in plant-based diets on growth performance, nutrient digestibility and digestive enzyme activities of juvenile mori (Cirrhinus mrigala)

The present experimental study was conducted to determine the effects of xylanase supplementation on growth performance, nutrient digestibility and digestive enzyme activities of mori, Cirrhinus mrigala. Mori with an initial body weight of 8.34 ± 0.23 g were fed seven experimental diets: a diet with high fish meal content (positive control, PC), a diet with high plant content (negative control, NC), and five other diets with increasing levels of xylanase (680, 1273, 1882, 2486 and 3091 U/kg). Each diet was fed to triplicate groups of 15 fish each for 60 days. After the trial termination, supplementation of xylanase significantly improved final weight (FW), weight gain (WG) and specific growth rate (SGR) compared to NC diet. The best feed conversion ratio (FCR) was observed at 1882 U/kg of xylanase supplementation level which was non-significant (P > 0.05) to PC diet (high fish meal content). Whole body proximate composition and apparent digestibility coefficient (ADC%) for dry matter (DM), crude protein (CP), crude fat (CF), crude ash (CA) and gross energy (GE) were significantly affected by xylanase supplementation. Activities of hepatopancreatic and intestinal amylase, protease and lipase showed an increasing trend with the increase in xylanase supplementation level, peaking at 1882 U/kg of xylanase (non-significant (P > 0.05) to PC diet) and declining thereafter (2486 U/kg-3091 U/kg). Quadratic regression analysis showed that 1948 U/kg of xylanase was the optimum value for supplementation of xylanase in plant-based diet. In conclusion, exogenous xylanase supplementation improved the growth performance, nutrient digestibility and digestive enzyme activities in juvenile mori fed plant-based diet.

Digestibilidade aparente dos nutrientes e balanço de nitrogênio de cordeiros terminados em confinamento alimentados com resíduo úmido de cervejaria como fonte de volumoso

The objective of this experiment was to evaluate the effect of wet brewery residue (RUC) levels as a forage source on the apparent digestibility of nutrients and nitrogen balance of feedlot lambs. The treatments consisted of four levels of RUC as forage, as follows: 31; 44; 57 and 70 % on a dry matter basis. The increase in the level of RUC as a roughage in the diet leads to a linear decrease (P≤0.01) of the digestibility coefficients of dry matter and organic matter. N intake decreased linearly (P≤0.05) with increasing dietary RUC level.

Apparent digestibility coefficients of selected protein ingredients for juvenile Totoaba macdonaldi

AbstractTwo feeding trials were performed to evaluate the apparent digestibility coefficients (ADCs) of dry matter, protein, and amino acids of three animal‐origin and four plant‐origin ingredients in Totoaba macdonaldi. In the first feeding trial, the animal‐origin ingredients were evaluated using totoaba juveniles with an initial weight of 529.7 ± 104.2 g, and for the second feeding trial 745.9 ± 210.6 g. Evaluated ingredients were: poultry by‐product meal, meat and bone meal, feather meal (FM), soy protein concentrate, soybean meal (SBM), corn gluten (CG), and wheat gluten (WG). Each experimental ingredient was evaluated in triplicate. ADCs of dry matter ranged from 35.9% for FM to 67.9% for poultry by‐product, while the protein ADCs values ranged from 41.7% for CG to 83.2% for poultry by‐product. Fish meal ADC (79.6%) was similar to poultry by‐product but significantly higher than WG and soy protein concentrate (72.5% and 72.6%, respectively). The ADCs for lysine were significantly higher for WG, sardine meal, poultry by‐product, and SMB (94.5%, 79.8%, 79.4%, and 79.4%, respectively). Based on the results from the present study, poultry by‐product, WG, and soy protein concentrate are the most promising alternative ingredients (i.e., to the fishmeal) for the formulation of totoaba grow‐out feeds.

Effects of fishmeal substitution by four fermented soybean meals on growth， antioxidant capacity and inflammation responses of turbot juveniles (Scophthalmus maximus L.)

A 10-week feeding trial was conducted to examine the effects of fishmeal (FM) substitution by different types of FSBM on growth performance, antioxidant capacity and inflammatory responses of turbot juveniles (Scophthalmus maximus L.). Four strains of microorganisms Saccharomycopsis fibuligera isolate Y27 (SF), Bacillus tequilensis KCTC 13622 (BT), Bacillus subtilis strain D7XPN1 (BS) and Bacillus aryabhattai B8W22 (BA) with high-efficiency degradation of glucoside of soybean isoflavones (SI) were obtained through screening and isolation, and were used to ferment soybean meal (SBM) to enhance the utilization of SBM. Six isonitrogenous (50.05% crude protein) and isolipidic (10.46% crude lipid) diets were formulated. The FM diet (the control diet) was formulated with 55% fishmeal. Five experimental diets (Diets SBM45, SF45, BT45, BS45 and BA45) were formulated by replacing 45% of FM inclusion level of control diet using SBM or either FSBM produced by the above four strains, respectively. Results showed that there was a significant decrease in feed intake (FI) of fish fed the SBM45 diet than those of the control and either FSBM diets (P = 0.000), and no significant difference was found among the control, SF45, BT45 and BS45 groups (P > 0.05). Meanwhile, fish fed the diet BA45 showed a significantly higher FI compared with the control group (P = 0.000). The appetite-stimulating factor (agouti gene-related protein, agrp1) gene expression was significantly up-regulated in fish fed the diet SF45 compared with the SBM45 group (P = 0.058). Meanwhile, the appetite-suppressive factors (proopiomelanocorein, pomc and cocaine and amphetamine regulated transcript, cart) gene expression was significantly down-regulated in fish fed the diet SF45 compared with the SBM45 group (P = 0.009, 0.006). The foregut α-amylase and trypsin activity were significantly promoted in fish fed the diet BS45 compared with those of the SBM45 and BA45 treatments (P = 0.000). There was a significant decrease in apparent digestibility coefficient of dry matter in fish fed the SBM45 diet compared with fish fed the control diet and fish fed either FSBM-based diet (P = 0.000), however, no significant difference was found among the control, SF45, BS45 and BA45 groups (P > 0.05). Moreover, no significant difference was observed in survival rate among dietary treatments (P > 0.05). Fish fed the diet BT45 had significantly lower feed efficiency than that of the control group (P = 0.048), meanwhile no significant difference was found among the control, SBM45, SF45, BS45 and BA45 treatments (P > 0.05). Fish fed the SBM45 diet had significantly lower specific growth rate compared with fish fed the control diet and fish fed either FSBM-based diet (P = 0.000). Furthermore, the antioxidant capacity significantly increased in fish fed the control and four FSBM diets compared with the SBM45 group (P < 0.05). The serum, liver and hindgut inflammatory responses of fish fed the control and four FSBM diets were significantly lower than those of the SBM45 group (P < 0.05). In conclusion, fish fed four FSBM diets could promote growth, enhance antioxidant capacity and reduce inflammatory responses of turbot juveniles compared with those of the SBM45 group.

Fishmeal substitution with low-gossypol cottonseed meal in the diet for juvenile turbot (Scophthalmus maximus L.): Effects on growth, nutrients utilization and haematological responses

An 8-week feeding trial was carried out to explore the effects of fish meal replacement with low-gossypol cottonseed meal, a potential alternative protein source, in juvenile turbot (Scophthalmus maximus L.). Five isonitrogenous and isoenergetic diets, with different substitutional levels (0%, 15%, 25%, 35% and 45%, respectively), were formulated. The growth performance, feed utilization and haematological responses were determined. Compared with the fishmeal group, fish growth was not affected when the replacement level was no more than 35%. The feed efficiency ratio and protein efficiency ratio in LC45 group were significantly lower. The apparent digestibility coefficients (ADCs) of dry matter and crude protein, as well as the ADCs of lysine and proline, were inhibited when the replacement level reached 25%. Furthermore, the glucose and cholesterol levels in plasma in LC45 group were significantly lower than that in FM group. Significantly lower content of malondialdehyde was observed in LC25 group while the activities of alanine aminotransferase and aspartate aminotransferase in LC45 were significantly induced. The height of intestinal villi in LC45 was significantly lower than in other groups. Overall, the results indicate that low-gossypol cottonseed meal could be used as an alternative plant protein source in turbot and it could replace 35% fishmeal in the diet.

Spineless cactus-based diets associated with various nitrogen sources in sheep diets

This study evaluated the effects of various nitrogen (N) sources augmenting spineless cactus-based diets on intake, digestibility, rumen kinetics and N balance in sheep. Eight rumen-fistulated sheep with an average initial bodyweight of 62 ± 6.83 kg were allotted to one of two 4 x 4 Latin squares. The diets consisted of spineless cactus (Nopalea cochenillifera), Tifton hay, corn grain, vegetable oil and a mineral mixture augmented with either soybean meal (SBM), cottonseed meal (CSM), whole cottonseed (WCS) or urea (U) to provide additional nitrogen. Dry matter (DM), crude protein (CP), and neutral detergent fibre (NDF) intakes were similar (P &gt;0.05) for sheep fed the diets with SBM, CSM, and WCS. The digestibility coefficients of DM and CP were similar (P &gt;0.05) for SM, CM, and U diets. The rate of DM disappearance from the rumen did not differ (P &gt;0.05) between treatments. However, the rumen ammonia, pH and N balance was higher (P &lt;0.05) for sheep fed the WCS and U diets. The N absorbed and N retained did not differ (P &gt;0.05) between the diets. Soybean meal and CSM are similar in their effects and can be used for sheep in diets based on spineless cactus. Whole cottonseed and U are interesting sources of N but should be used with caution owing to their effects on digestibility and nutrient intake in sheep.

243 Assessment of Modified Corn Protein as a Protein and Energy Source for Nursery Pigs

Abstract Our objective was to evaluate modified corn protein (MCP) as a protein and energy source in nursery pig diets. A total of 198 weaned pigs (6.25 ± 0.95 kg BW) were assigned across 18 pens (11 pigs/pen) and 2 dietary treatments using a complete randomized design. Pigs were fed in 3 phases consisting of 7, 14, and 21 d respectively. In phases 1 and 2, diets included: 1) Control or 2) 10% MCP, while all pigs were on a common phase 3 diet. Diets were formulated to be iso-caloric with SID Lys at 1.45, 1.40 and 1.35% for phases 1, 2 and 3 respectively. Pigs were weighed and feed disappearance measured to calculate ADG, ADFI and G:F within phase and overall. At the end of phase 2, fecal samples were collected for determination of apparent total tract digestibility coefficients (ATTD) for dry matter, energy and nitrogen. Pen was considered the experimental unit and all data were analyzed using the mixed procedure of SAS with treatment as a fixed effect. In phases 1 and 2, ADG, ADFI and G:F did not differ between Control and MCP treatments (P &amp;gt; 0.05). Similarly, performance did not differ between treatments in phase 3 (P &amp;gt; 0.05). Overall, end BW (25.7 vs. 25.3 kg), ADG (0.42 vs. 0.44 kg/d), ADFI (0.58 and 0.61 kg/d) and G:F (0.71 vs. 0.70) did not differ (P &amp;gt; 0.05) between the Control and MCP treatments, respectively. However, compared with the Control, phase 2 ATTD coefficients for dry matter (80.6 vs. 78.2%), nitrogen (77.5 vs. 75.2%) and gross energy (79.7 vs. 76.9%) were significantly reduced in the MCP treatment (P &amp;lt; 0.05). In conclusion, MCP provided equal nursery pig performance when used as an alternative protein and energy source in diet formulations despite lower ATTD.

Supplementation of a Multienzyme Complex, an Organic Acid-Essential Oil Complex, and Prebiotic Alone or in Combination Affects Growth, Nutrient Utilization, and Immune Function of Rainbow Trout (Oncorhynchus mykiss)

Dietary supplementation of functional additives is an effective strategy to improve the nutritive value of low fish meal diets for fishes. The present study is aimed at investigating the dietary effects of a multienzyme complex, an organic acid-essential oil complex and prebiotic on growth, immune function, and intestinal health of rainbow trout (Oncorhynchus mykiss). A positive control diet (PC) and a negative control diet (NC) were formulated to contain 200 g/kg and 100 g/kg of fishmeal, respectively. Seven other diets were formulated by supplementing a multienzyme complex (MC, 0.125 g/kg), organic acid-essential oil complex (OEC, 0.5 g/kg), and prebiotic (P, 2 g/kg) alone or in combination to the NC diet (MC, OEC, P, MC+OEC, MC+P, OEC+P, MC+OEC+P). All diets were formulated to be isoproteic (434.3 g/kg-439.1 g/kg) and isolipidic (119.2 g/kg-125.9 g/kg) and fed to rainbow trout of 7.66 ± 0.05 g for 56 days. The weight gain, apparent digestibility coefficient of dry matter, protein efficiency ratio, and protein retention efficiency were significantly increased, and feed conversion ratio was significantly decreased by the three additives alone or in combination ( P &lt; 0.05 ) compared to the NC. No significant differences in growth performance and feed utilization were observed among the treatment groups. Compared to the NC group, serum alanine transaminase, aspartate transferase activities, and malondialdehyde content reduced significantly, while serum superoxide dismutase increased in all except for the MC group, and alkaline phosphatase and lysozyme activity increased in all except for the MC and MC+P groups ( P &lt; 0.05 ). The foregut protease activity of the MC+P and OEC+P groups and the amylase activity of the OEC and MC+OEC groups were significantly higher than those of the NC group ( P &lt; 0.05 ). The villus height of P, MC+OEC, and OEC+P groups, the villus width of MC group, and the muscle thickness of MC, MC+OEC, and MC+OEC+P groups were also significantly higher than those of the NC group ( P &lt; 0.05 ). Compared to the PC group, the richness and diversity of intestinal microorganisms in the NC group and all the supplemented groups were significantly reduced ( P &lt; 0.05 ), but no differences among them ( P &gt; 0.05 ). In conclusion, the individual or combined supplementation of multienzyme complex, organic acid-essential oil complex, and prebiotic in a low fish meal diet (100 g/kg) improved the growth performance, nutrient utilization, and immune function of rainbow trout, but no synergistic effects were observed in the combination of the three supplements.

NUTRIENT DIGESTIBILITY AND NITROGEN UTILIZATION OF LACTATING COWS WHEN RECEIVING A FOOD MIXTURE WITH MINERAL SUPPLEMENTS

The article presents results of studies on giving natural mineral additives from the deposits of Oryol (Stimulus) and Bryansk regions (smectite tripoli) in the composition of the feed mixture to lactating cows of the second lactation of the black-and-white breed in the agricultural enterprise OOO "Mololchnoye" of Bryansk region. A comparative analysis of the effect of two dosages of their inclusion in the ration - 3 and 4% of the dry matter without changing their energy nutritional value on productivity, digestibility of nutrients and nitrogen usage in the organism of lactating cows was carried out. A positive effect on the level of milk productivity of both natural mineral additives was found, however, more significant changes in protein and lipid metabolism occurred in the body of cows who received smectite tripol as part of the feed mixture at a dose of 4% of the dry matter of the ration. Thus, the dry matter digestibility coefficients, including organic matter, as well as protein and crude fat digestibility coefficients of lactating cows that received smectite tripoli (4%) significantly exceeded similar parameters in all experimental groups. Based on the results of the balance experiment, a positive nitrogen balance of lactating cows of all groups was established. Concurrently, a redistribution of digested nitrogen with a higher transformation into products was noted, which is confirmed by a large percentage of its transition into milk (10.3%). This redistribution of nitrogen in the body of lactating cows of the experimental groups became possible due to its lower retention in the body (by 5.9% due to "Stimulus" additive and by 11.0% - smectite tripoli). Therefore, based on the obtained experimental data, it is possible to recommend to include smectite tripoli natural mineral additive at a dose of 4% of the dry matter of the ration into the feed mixture for lactating cows.

Water restriction periods affect growth performance and nutritional status of Santa Inês sheep in the Brazilian Semi-arid

This study aimed to assess the growth performance and nutritional status of sheep under intermittent water supply by means of performance, intake, apparent digestibility of nutrients, water balance and nitrogen. Thirty-two intact male sheep (20.7 ± 2.63 kg, 8 months of age) were distributed in a completely randomized design with 4 water supply intervals via drinking trough (0h00, 24h00, 48h00, and 72h00), with 8 replicates. The extension in the water restriction period caused a reduction in the intake of dry matter, crude protein, neutral detergent fiber, digestible energy, and metabolizable energy (P &lt; 0.05). The digestibility coefficients of dry matter, crude protein, and neutral detergent fiber showed a linear decrease with increasing periods of water restriction (P &lt; 0.05). Water intake via food, total water intake, and water excretion via feces showed a linear increase in response to an increase in the water supply interval (P &lt; 0.05). Water intake via drinking, metabolic water, total water excretion and water balance presented a linear decrease, with increasing periods of water restriction (P &lt; 0.05). Nitrogen intake and absorbed nitrogen were influenced by water restriction, presenting a linear decreasing trend according to water supply periods (P &lt; 0.05). Final weight, daily weight gain, and total weight gain, were influenced by the periods of water restriction, showing a linear reduction (P &lt; 0.05). Feed conversion increased as the water restriction period increased (P=0.004). Intermittent water supply at intervals of up to 72h00 reduced nutrient intake and digestibility, resulting in a decrease in weight gain of the studied animals.

Sources of acid insoluble ash as marker of corn digestibility in broilers

The objective was to evaluate three sources of acid insoluble ash (AIA) (celite, kaolin, and sand), as indicators, to determine the apparent metabolizable energy of corn on a natural matter (AME) basis, dry matter digestibility coefficient (DMDC), and crude protein digestibility coefficient (CPDC) using total and partial excreta collection methods. Two hundred and ten Ross broiler chicks of 18 to 27 days of age were used. Broilers were adapted to experimental the diet for four days, and excreta were collected for 5 days. A reference diet (RD) based on corn and soybean meal was prepared to meet the nutritional requirements of the birds. A test diet was prepared with 40% replacement of RD with corn. The formulated diets were: D1, 99% Reference diet + 1% celite; D2, 59.4% RD + 39.6 % corn + 1% celite; D3, 99% Reference diet + 1% kaolin; D4, 59.4% RD + 39.6 % corn + 1% kaolin; D5, 99% Reference diet + 1% sand; D6, 59.4% RD + 39.6 % corn + 1% sand. The treatments were distributed in a completely randomized design, with six diets and five replicates of seven birds each in a 2x3 factorial arrangement. There were significant interactions for all variables investigated. It was observed that the AME and DMDC values of corn were similar in the two methods of collection, and PDC values using kaolin and celite makers were similar. However, the AME and CPDC of corn using sand with partial collection method were underestimated by 17.70 and 15.53%, respectively compared to those with the total collection method. The AME values of corn with the collection methods using celite and, the DMDC using celite and sand were significantly different. It was observed that the DMDC using celite and sand provided significantly lower values (4.67 and 5.15%), respectively, and the AME using celite was 2.86% lower than that obtained by total collection. To determine the EMA, DMDC, and CPDC in broilers, it is more efficient to use celiteTM and kaolin as markers with partial collection of excreta. Sand should not be used with partial excreta collection method, because it provides lower values of AME and CPDC compared to with total excreta collection method.