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To develop specific recommendations on the feeding strategies for farmed lumpfish, four duplicate groups (n = 70; N = 280) of lumpfish with a mean ± SD start weight of 30.4 ± 5.3 g were distributed among eight sea cages (5 × 5 × 5 m) each stocked with 220 one year old Atlantic salmon with a mean (± SD) weight of 1485.9 ± 213.2 g. The fish were fed either pelleted feed at 3% BW−1 or with feed blocks at 1.5%, 2% and 3% BW−1 respectively for 66 days. There were clear differences in growth performance between the four treatment groups with lumpfish fed with pelleted feed attaining the highest weight gain. There were only minor histopathological changes observed between the dietary treatments with mainly mild focal and multifocal inflammation observed in sampled tissues. There were no significant differences in liver vacuolisation between the dietary groups and baseline samples with most of the livers evaluated appeared to be vacuolized within what is regarded as normal range for all four treatment groups. Only minor differences in welfare score between the four treatment groups were found. The incidence of cataracts varied between the treatment groups and was correlated to differences observed in growth between the four groups. Lumpfish fed once daily from automatic feeders with pelleted feed had the highest incidence and severity of cataracts. This study suggests that feeding lumpfish with moderate amounts of feed blocks (≤ 2% BW−1) may be advantageous for maintaining slow growth and good welfare in salmon cages, and this should be further tested in large scale studies in commercial salmon farms. • We assessed growth, cataract development, welfare score and gut histopathology in lumpfish fed either pelleted feed or with feed blocks. • Lumpfish fed with pelleted feed attaining the highest weight gain. • Lumpfish fed with pelleted feed had the highest incidence and severity of cataracts. • Only minor histopathological changes observed between the dietary treatments. • Feeding lumpfish with moderate amounts of feed blocks (≤ 2% B−1) in salmon cages is recommended. [ABSTRACT FROM AUTHOR]

Abstract Three duplicate groups of individually tagged lumpfish (mean initial weight: 22.3 ± 2.5 g) were fed either daily (7DW); four days per week (4DW) or three days per week (3DW) at a feeding rate of 2% body weight day−1 for a period of 126 days. There were significant differences in growth rates between the groups with the 7DW fish having the highest growth rates. Cataract prevalence was 53% lower in the 3DW group compared to the 7DW group. Histological examination showed that in some individuals in all three groups there was moderate expansion of the lamina propria in the mid and hind gut regions of the intestine with tissue most likely to represent fibrous tissue with scattered leucocytes. The severity of inflammation appeared to increase the more frequent the fish were fed with the 7DW fish having the highest inflammation score in these tissues. Feeding fish daily also resulted in higher levels of liver vacuolisation and chronic inflammation of the lamina propria in the mid and hind gut region of the intestines. Results from the present study show that restricted feeding regimes can be used to control growth and improve gut and eye health in lumpfish. Highlights • We assessed growth, cataract development and gut histopathology in lumpfish feed 7, 4 and 3 days per week (DW). • Growth and cataract prevalence was lowest in the 3DW group. • Liver vacuolisation and chronic inflammation in the gut was higher in the 7DW group. [ABSTRACT FROM AUTHOR]

Changing trends in fish feed formulation, with progressively higher inclusion levels of plant ingredients, are invariably introducing more fibre despite the fact that this component cannot be utilized by most fish. The effects of increasing insoluble dietary fibre level on growth, nutrient utilisation, blood parameters and gut health in European sea bass ( Dicentrarchus labrax L.) were studied over a period of 117 days. Moreover, investigation on digesta transit time through gastrointestinal evacuation pattern and digesta characteristics (moisture of digesta) were studied. Five isoproteic diets were formulated to contain increasing insoluble fibre levels, neutral detergent fibre, NDF (7.2, 8.9, 11.5, 13.1 and 15.5%) derived by the inclusion of sunflower hulls and soybean hulls. No significant differences due to fibre inclusion levels were observed in final body weight, specific growth rate, feed intake, feed conversion rate, protein and lipid efficiency. No significant differences in serum total protein, glucose, triglycerides, alkaline phosphatase and inorganic phosphorous were found. All the histological sections showed normal intestinal architecture, and inflammatory and/or degenerative changes were not present in any histological section from all subjects examined. The investigation into gastrointestinal evacuation pattern revealed no significant differences between treatments, however higher dietary fibre levels seem to increase the time required to empty the stomach while the time required to empty 90% of the hindgut content was similar in all the treatments: around 46–47 h. No differences were found between diets in the moisture content of digesta along the digestive tracts. We can conclude that the different insoluble fibre levels tested in this trial have no effects on overall performances and feed efficiency in European sea bass. Results from blood biochemistry profile and histology confirm good nutritional and health status of fish under all feeding treatments. The inclusion of fibre had no influence on digesta transit time. In formulation of feed for the on-growing of European sea bass insoluble fibre derived from sunflower hulls and soybean hulls can be included at a level of up to 15.5%. [ABSTRACT FROM AUTHOR]

The present study was carried out to evaluate growth, gut histology and gut bacterial community of gilthead sea bream ( Sparus aurata ) fed with increasing dietary soybean meal (SBM) levels in a low fishmeal (FM) based diet, in comparison with a control diet. Five isoproteic and isolipidic experimental diets were formulated to contain increasing levels of SBM (0, 100, 200, and 300 g kg −1 named S0, S10, S20 and S30, respectively) with 150 g kg −1 of FM, and one control diet (C) without SBM and containing 350 g kg −1 of FM. Sixty sea bream (initial body weight 75.9 ± 1.9 g, n = 900) per tank were reared in a recirculation system at 23.0 ± 1.0 °C and fed to satiation. The trial was run in triplicate and lasted 100 days. At the end of the trial fish fed the S30 diet showed a higher ( P ≤ 0.05) specific growth rate (SGR) compared to S0 (SGR, 1.17 ± 0.03, 1.20 ± 0.01, 1.22 ± 0.01, 1.25 ± 0.01 and 1.21 ± 0.04 for S0, S10, S20, S30 and C, respectively), and a higher feed intake (FI) compared to S0, S10 and S20. Sea bream fed the C diet had a higher ( P ≤ 0.05) FI compared to S0 (FI, 1.40 ± 0.01, 1.45 ± 0.01, 1.44 ± 0.03, 1.51 ± 0.03 and 1.46 ± 0.02 for S0, S10, S20, S30 and C, respectively). No significant differences in feed conversion rate, protein efficiency ratio, gross protein efficiency and gross lipid efficiency among the treatments were detected. No specific histopathological changes indicative of soy-induced enteritis were observed in the intestine of any fish examined. Gut bacterial community of the distal intestine content was analyzed by Next-Generation Sequencing. At the phylum level, the gut bacterial community was dominated by Firmicutes (relative abundance 71%), while the most represented family was Lactobacillaceae (26%). Even if no significant differences ( P ≤ 0.05) in the gut bacterial community α and β-diversity according to the different diets were detected, Cyanobacteria and Lactobacillaceae progressively increased from diet C to diet S30. In conclusion results of growth, nutrient utilization, gut histology and gut bacterial community indicate that SBM can be successfully incorporated up to a level of 300 g kg −1 with the inclusion of 150 g kg −1 of FM, without any deleterious effects on growth, protein utilization and gut health during the on-growing of sea bream. [ABSTRACT FROM AUTHOR]

The present study evaluated the effects of magnesium (Mg) on growth, antioxidant capacity, intestinal morphology and ammonia nitrogen resistance in juvenile oriental river prawn, Macrobrachium nipponense. Six semipurified diets (crude protein 401.1 g kg−1 diet; crude lipid 88.7 g kg−1 diet) containing Mg levels of 1.1, 1.4, 1.6, 2.1, 2.8 or 4.5 g kg−1 were formulated. A total of 1080 healthy juvenile prawns (0.151 ± 0.003 g) were randomly stocked into eighteen 300 L tanks (100 × 80 × 60 cm), each tank with 60 prawns. Each experimental diet was fed to prawns in triplicate twice daily (08:00 and 17:00) for eight weeks. After the feeding trial, 20 prawns from each tank were challenged with 37 mg/L ammonia nitrogen for 96 h, and the hemolymph, hepatopancreas and muscle of the rest of the prawns were collected. Final biomass was higher in prawns fed diets containing 1.6 and 2.1 g Mg kg−1 compared with those fed the diet with 1.1 g kg−1. Higher alkaline phosphatase (ALP) activity was obtained in the serum of prawns fed the 2.1 and 2.8 g Mg kg−1 diets. The highest activities of hepatopancreas superoxide dismutase (SOD), glutathione peroxidase (GSH-Px) and total antioxidant capacity (T-AOC) were observed in prawns fed 1.6–2.8 g Mg kg−1 of feed, and the lowest hepatopancreas malondialdehyde (MDA) concentrations and serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) activities were found in these treatment groups. Similarly, the prawns fed diets with 1.6 and 2.1 g Mg kg−1 had significantly lower MDA concentrations and cumulative mortality and higher antioxidant enzyme activities after ammonia nitrogen exposure. The intestinal epithelial cells were closely attached to the membrane in prawns fed the 2.1 g Mg kg−1 diet, but they were partly detached in those fed the 1.1 and 4.5 g Mg kg−1 diets. The minimum dietary Mg supplementations of juvenile M. nipponense were determined to be 1.6, 1.9, 2.0 and 2.2 g kg−1 feed, respectively, using broken-line regression analysis based on the final biomass, SOD, ALT and ALP. • Optimal dietary magnesium (Mg) enhanced antioxidant capacity and health of juvenile Macrobrachium nipponense. • After ammonia stress, prawns fed on 1.6 and 2.1 g Mg kg−1 had lower cumulative mortality and higher antioxidant capacity. • Dietary supplementation of 1.6–2.2 g Mg kg−1 feed is recommended to promote the growth and well-being of juvenile prawns. [ABSTRACT FROM AUTHOR]

A 60-day feeding trial was conducted to assess the effects of dietary Saccharomyces cerevisiae -originated free nucleotides on growth, innate immunity, intestinal histomorphometry and disease resistance in Nile tilapia, Oreochromis niloticus (average initial weight of 7.85 g). Five diets (treatments) were prepared: negative control diet (NCD) - basal diet without additives; positive control diet (PCD) - basal diet supplemented with a commercial nucleotide-based additive at 170 ppm; and three experimental diets, N170, N320 and N470, supplemented with S. cerevisiae -originated free nucleotides at 170, 320 and 470 ppm, respectively. There were no significant differences in production parameters after the trial period. Nevertheless, the complement hemolytic activity was higher in fish subjected to the three experimental diets, while serum lysozyme concentration was higher in the N470 group compared with both controls. Intestinal villi height and density were greater in fish fed the N470 diet compared with the NCD group. In addition, fish receiving the three experimental diets showed higher absorption surface area magnification ratio, with the greatest values being observed in the N470 group. Lastly, the highest survival rate following Aeromonas hydrophila challenge was recorded in the N470 group. Taken together, the present findings indicate that supplementation of feed with S. cerevisiae -originated free nucleotides at 470 ppm improves non-specific immune responses and intestinal microstructure morphology as well as increases survival rate after bacterial infection in Nile tilapia. Therefore, this blend of natural nucleotides has the potential of being used as an alternative to antimicrobials when included as an additive in aquaculture feeds. • Diets supplemented with Saccharomyces cerevisiae -originated free nucleotides were examined in Nile tilapia. • S. cerevisiae -originated free nucleotides promoted improvements in immunity and intestinal morphology in Nile tilapia. • Diets supplemented with S. cerevisiae -originated free nucleotides increased the survival rate after bacterial infection. [ABSTRACT FROM AUTHOR]

Abstract: The main aim of the current experiment was to assess the potential of dietary orange peel extract (OPE) and lemon peel extract (LPE) as promoters of broiler resistance to high ambient temperature. The experiment was conducted as a 2×3 factorial arrangement of treatments with 2 levels of OPE (0 and 200mg/kg feed) and 3 levels of LPE (0, 200, and 400mg/kg feed). At d 25, a total of 288 Ross 308 broilers were randomly assigned to 6 dietary treatments with 4 replicates of 12 broiler chickens each. The temperature was increased to 34°C with 50% relative humidity for 5h daily starting from d 28 until d 38. At the end of the trial (d 38), 4 male broiler chickens per pen were sampled for determination of serum components and variables of intestinal morphology. Dietary OPE and LPE did not affect weight gain, feed intake, and feed conversion ratio of broiler chickens. The inclusion of 200mg/kg OPE increased serum total protein, but reduced serum lactate dehydrogenase and creatine phosphokinase activity in broiler chickens (P<0.05). Lemon peel extract supplementation decreased the activity of lactate dehydrogenase quadratically (P=0.039) and creatine phosphokinase linearly (P=0.037). No differences in the other blood characteristics and intestinal traits were observed with the exception of muscularis thickness of duodenum, which was reduced when LPE was added to the diet (linear, P=0.011). These results indicate that OPE, LPE, and their combination might modify some blood components and the proximal intestinal morphology, but without beneficial effect on growth performance of broiler chickens under hot conditions. [Copyright &y& Elsevier]

Abstract: This work tested the effect of replacing zinc bacitracin with a blend of caproic and caprylic acids in a diet including colistin on growth performance, mortality, gut histology and development of intestinal lymphoid tissues in rabbits experimentally infected with Escherichia coli and Clostridium perfringens. Three experimental diets were formulated: a control non-medicated diet (diet C), diet C medicated with 150mg zinc bacitracin and 120mgcolistin/kg (diet B) and diet C supplemented with a 4-g mixture of the acids and 120mgcolistin/kg (diet A). Forty rabbits weaned at 28days of age and housed individually were assigned to each diet. At 35days of age, rabbits were orally infected with 109 cfu of E. coli and 109 cfu of C. perfringens. At 35 and 56days of age, five rabbits per diet and age were slaughtered to assess caecal traits, jejunal histology and follicular development in the caudal ileal Peyer''s patch and the appendix. No significant differences were reported on growth performance. Mortality rate reached 60.0% for control rabbits whereas no mortality occurred in rabbits fed the supplemented diets. Caecal pH was not influenced by diet but was lower at 56 than at 35days (6.20 vs. 6.49, P<0.001). No differences were detected on villus height of control rabbits between 35 and 56days of age (average height of 597μm) but villi of rabbits fed diets B and A were, respectively, 19 and 34% (P<0.001) longer at 56days than at 35days. The average follicle area in the Peyer''s patch (81,900μm2 vs. 56,800μm2, P<0.001) and in the appendix (116,000μm2 vs. 56,900μm2, P<0.001) increased after the infection. Besides, average follicle area of the Peyer''s patch was influenced by diet (78,983μm2 vs. 69,632μm2 vs. 59,457μm2, P=0.011, for diets C, B and A, respectively). No significant effect of treatments was detected on the number of follicles of the appendix (37.2 follicles on average). To conclude, the substitution of caproic and caprylic acids for zinc bacitracin in a diet including colistin increased jejunal villus height and reduced follicle hypertrophy of the caudal ileal Peyer''s patch in growing rabbits experimentally infected with C. perfringens A and E. coli O103. The dietary combination of colistin with both zinc bacitracin and the blend of esterified caproic and caprylic acids prevented the rise of fattening mortality, even after the infection. However, the effect of including medium-chain organic acids in a diet free of medication on challenged rabbit health is yet to be elucidated. [Copyright &y& Elsevier]

The effect of metabolic efficiency and associated gut characteristics of laying hens on the variability of transfer of dietary n-3 polyunsaturated fatty acids (PUFA) to the egg was examined in laying hens at 56 wk of age. An empirical energetics model was used to categorize individual hens into energetically efficient or nonefficient treatments based on residual maintenance ME requirement. Birds were then provided a diet containing an extruded flax product as a source of n-3 PUFA for 14 d. Egg traits were determined and yolks collected at 0 d and 14 d for measurement of fatty acid composition and variation in fatty acid levels within hen efficiency class. Gut length and duodenal histomorphometric indices were assessed after the 14-d experimental period. Efficient hens had a 96.01% rate of lay compared with 88.63% in nonefficient hens. After 14 d of feeding, the concentration of n-3 PUFA increased (151.6 vs. 315.8 mg/egg) in the egg yolk whereas n-6 PUFA, saturated fatty acids, and monounsaturated fatty acids were reduced (P < 0.001). Energetic efficiency had no additional effect on these measurements. However, egg yolks from efficient birds had less α-linolenic acid but more docosapentaenoic acid than nonefficient birds, suggesting a greater up-conversion of medium-chain (α-linolenic acid) to long-chain fatty acids (docosapentaenoic acid) in efficient birds. After 14 d, the CV for total n-3 PUFA in egg yolks from efficient hens was lower than that from nonefficient birds (11.1 vs. 21.4), indicating a more uniform level of enrichment. Furthermore, efficient hens had longer duodenal villi (P = 0.02), resulting in a greater absorptive villi surface area (0.13 mm2/villi) than in nonefficient birds (0.10 mm2/villi; P = 0.01). Increased uniformity of n-3 PUFA enrichment of table eggs could be possible through focus on metabolic efficiency and gut absorptive condition in laying hens. [ABSTRACT FROM AUTHOR]

Abstract: A trial on turbot (Psetta maxima) juveniles was undertaken to evaluate the effect of replacing dietary fishmeal (FM) with a complementary mixture of plant proteins (PP) consisting of soybean meal (SBM), wheat gluten meal (WGM) and corn gluten meal (CGM). Four practical diets were formulated to progressively replace 25% (PP25), 39% (PP39), 52% (PP52) and 66% (PP66) of FM protein. Forty animals per tank (initial weight 24.2±4.4g) were randomly distributed into twelve 450-liter square tanks connected to a closed recirculation system (temperature 18±1°C). The diets were tested in triplicate for 77days. Final weight ranged from 126.6g (PP25) to 99.5g (PP66). Voluntary feed intake of group PP66 (55.5gfish−1) was significantly lower than in PP25. Specific growth rate in fish fed diet PP25 (2.14% day−1) was significantly higher than those found both in PP52 (2.01% day−1) and PP66 (1.82% day−1) groups. Feed conversion ratio (FCR) in groups PP25 and PP39 (0.66–0.67) was lower in comparison with those of the other groups (FCR 0.70–0.74). None of the diets affected whole-body composition and hepatosomatic index. Condition factor significantly decreased with increasing dietary PP (2.06, 2.02, 1.97 and 1.91) whereas a significant increase in viscerosomatic index was observed in fish fed PP52 and PP66 (6.70–6.95) in comparison with the other two groups (6.31–6.21). Reduced protein retention was found in groups fed diet PP52 and PP66, with protein efficiency ratio (PER) ranging from 2.71 to 2.63 and gross protein efficiency (GPE) from 40.3 to 40.0, in comparison with the other two groups (PER 2.83 and GPE 45.5–45.8), even though apparent digestibility coefficients were not reduced. Ammonia excretion, (g total ammonia nitrogen 100gproteinintake−1), was significantly higher for group PP25 (3.41) than group PP52 (2.61). Gut histology examined in four different sites of intestine (pyloric caeca, proximal, intermediate and distal intestine) revealed no noticeable differences among fish of the various diet groups. In conclusion, substitution of a mixture of SBM, WGM and CGM for up to 52% of FM protein did not reduce feed intake, and at 39% substitution, turbot maintained optimal growth rate and nutrient utilization. Worsened FCR of fish fed diets containing higher plant protein levels was not associated with a reduced digestibility of ingredients or alterations of gut histology. [Copyright &y& Elsevier]

Abstract: Two experiments were conducted in order to investigate the effect of dietary mannan oligosaccharides (MOS) on gilthead sea bream (Sparus aurata). Experiment I was designed to assess the effect of dietary MOS (0%, 0.2% and 0.4%) on fish fed diets containing fishmeal (FM) as the only protein source. Experiment II was designed to assess the effect of MOS (0% and 0.4%) on fish fed soybean meal (SBM) as a partial replacement of FM (SBM inclusion 31% of diet). After 9weeks feeding on the experimental diets growth parameters, body composition, liver and intestinal histology and intestinal microbial diversity were assessed. The results showed that mean final weight, specific growth rate (SGR), feed conversion ratio (FCR) and protein efficiency ratio (PER) remained unaffected by MOS supplementation of fish fed FM or SBM diets. However, compared to the control group (FM0), condition factor (K) and hepatosomatic index (HSI) were significantly lower in fish fed 0.2% MOS (FM02) and 0.4% MOS (FM04), respectively. These parameters were unaffected in SBM-fed fish. Body proximate composition remained unaffected by MOS supplementation in fish fed either FM or SBM diets (P >0.05). Histological evaluation revealed that MOS had no effect on glycogen deposition in liver and no effect on gross villi morphology in the anterior intestine in either Experiment I or II. However, relative to the control groups (FM0) dietary MOS appeared to improve gross morphological absorptive surface area in the posterior intestine in Experiment I. Electron microscopy revealed that dietary MOS had a pronounced effect at the ultrastructural level in both experiments, as microvilli density and length were elevated in both intestinal regions in fish fed both the FM and SBM based diets. No significant histological differences were found between respective FM0 and SBM0 groups. DGGE analysis revealed that both SBM and MOS affected the intestinal microbial species richness and diversity. However, the effect of dietary MOS on the gastrointestinal microbiota was more pronounced in FM-based diets (Experiment I) as was reflected by increased species richness and diversity and reduced similarity between microbial profiles of the different FM groups. The effect of MOS in Experiment II on SBM-fed fish was marginal, as species richness and diversity remained unaffected and similarity between microbial profiles of the SBM groups and replicates remained high (i.e. >80%). Dietary SBM exerted a greater effect on gut microbiota than dietary MOS. [Copyright &y& Elsevier]

Abstract: Gram positive food-grade bacteria such as lactococci have significant advantages over attenuated pathogens as vaccine delivery vehicles because of their inherently greater safety. Plasmodium falciparum merozoite surface antigen 2 (MSA2) was expressed in recombinant Lactococcus lactis both intracellularly and covalently anchored to the peptidoglycan of the cell wall (MSA2cP). Balb/c mice of different ages were immunised with the MSA2cP expressing L. lactis in a combined oral and nasal immunisation procedure. Serum IgG antibody responses to MSA2 were higher in young adult Balb/c mice compared to old mice and neonates. The elicited serum IgG antibodies reacted with native MSA2 on the surface of P. falciparum merozoites in an immunofluorescence assay. The serum IgG antibody isotypes in young adult mice were mainly IgG1, IgG2a and IgG2b, while IgG3 tended to be higher in old mice. IgA antibodies to MSA2 were also produced in young mice. Enlarged mesenteric lymph nodes, and more prominent lymphoid tissue in the lamina propria of the ileum and lymphoid follicles in the spleen, were observed in mice fed L. lactis. These findings are relevant for developing L. lactis as a vector to deliver vaccines in human populations. [Copyright &y& Elsevier]

Efficacy of Goniothalamin a styryl-pyrone isolated from Goniothalamus wightii Hook.f. and Thoms, against beet armyworm, Spodoptera exigua (Hübner), populations was determined under laboratory condition. The experiments were carried out with concentrations of 5, 10, 15 and 30ppm in an artificial diet and compared with control insects. Laboratory bioassay showed that the goniothalamin had a strong effect on food utilization, moulting and gut histology. The food consumption and conversion of ingested and digested food to body matter decreased with increasing pyrone concentration. The antifeedant activity was also observed in larvae of S. exigua. The treated third instar larvae exhibited mortality in a dose dependent manner. At 5, 10, 15 and 30ppm/insect, the pyrone gave 23%, 45% 63% and 100% mortality respectively. The larvae of S. exigua gained significantly less weight until pupation in the 10 and 15ppm pyrone concentrations. Duration of larval period was also affected after treatment with pyrone. The metamorphosis was delayed with additional moulting (7th instar) after treatment with 10 and 15ppm of goniothalamin, the percentage of larvae successfully moulted into progressive instars was significantly decreased with an increase in pyrone concentrations. The effects of goniothalamin on midgut ultrastructure of third instar larvae of S. exigua were investigated by using light microscopy. Cross sections of the midgut showed that the epithelial cells were destroyed. Significant damage of the midgut epithelium was observed along with lysis. [Copyright &y& Elsevier]

Abstract: Effects of soybean meal (SBM) based diet on growth performance, histology of the intestinal epithelium and on the gut microbiota of juvenile rainbow trout (Oncorhynchus mykiss) were investigated on two trials lasting for 8 weeks (Trial I) and 18 weeks (Trial II). The microbiological characterization was done both with conventional plating techniques, biochemical profiling and length heterogeneity analysis of PCR amplified 16S rDNA (LH-PCR). Typical histological changes were found after 18 weeks of SBM feeding (Trial II). Mean height of simple foldings were significantly higher within the group fed with fish meal (FM) based diet. These changes were not, however, reflected in the appearance, behavior and weight gain of the fish, although the feed conversion rate (FCR) was higher, compared to fish fed with the traditional FM feed. In both SBM and FM groups the counts of cultivable intestinal bacteria dropped within the first 4 weeks of feeding (Trial I). Subsequently, the bacterial numbers increased in the FM group, but not in the SBM group by the 8th week of the trial. The LH-PCR data suggested also that diet-related qualitative changes in the microbiota had occurred (Trial II). The main identified bacteria were mainly representatives of the genera Aeromonas, Sphingomonas and Chryseomonas, and among the lactic acid bacteria, Lactococcus and Lactobacillus. Future research will be directed to the identification and eventual elimination the SBM-associated factors involved in the inflammatory responses and unfavorable FCR, in particular by modifying the intestinal microbiota. [Copyright &y& Elsevier]

Studies dietary protein sources and concentrations in mixed diets for dogs by researchers from Hannover, Germany. Influence of dietary protein source and manufacturing process on the macronutrient digestibility of commercial dog foods; Presentation of negative gastrointestinal effects such as poor fecal consistency in dogs fed with certain animal proteins; Investigation on the effects of two different dietary protein sources in two groups of healthy dogs.

We examined effects of administering biogenic amines (putrescine, cadaverine, tryptamine, β-phenylethylamine, spermine and histamine) to 15 weaned Saanen kids (2 months old; 11.6±1.4 kg BW) for 14 days. The kids were randomly assigned to three groups: control (no amines), oral dose (OD), 1.4 g per day of amines by oral administration, and feed dose (FD), 1.4 g per day of amines mixed with the diet. DMI and body weight (BW) were recorded daily before morning feeding. On day 15, the OD and control animals were slaughtered and selected muscles analyzed for physical characteristics. Samples of rumen, abomasum, liver, pancreas, duodenum, jejunum, and distal ileum were analyzed histologically. In the OD group, DMI and growth rate were reduced compared to control group and a smaller effect on the same variables was observed in FD group. On day 14, BW was lower (P<0.05) in the OD group than controls and the FD group. Meat quality was also affected by the treatment in that muscle drip loss and color (redness and yellowness) were increased. Microscopic analysis showed that direct oral administration of amines had a negative effect on the histological characteristics of all the visceral organs examined. Oral amine administration therefore has detrimental effects on the parameters investigated in post-weaning Saanen kids. [Copyright &y& Elsevier]

Fatty acid ethyl esters (FAEE) are a potential alternative to fish oil as a source of polyunsaturated fatty acids in fish feeds. This investigation examined the growth performance, lipid composition, and intestinal and liver histology of rainbow trout (Oncorhynchus mykiss) fed experimental starter diets with graded levels of FAEE and fish oil. Five experimental diets were formulated with 20% total lipid content and 0%, 25%, 50%, 75%, and 100% replacement of Alaskan Pollock oil with FAEE oil, and they were formulated with analogous fatty acid levels. The five diets used defatted fish meal as the primary protein source, and a sixth diet was included that used full-fat fish meal and extracted fish oil. Triplicate groups of rainbow trout (144 ± 20 mg initial weight) were fed experimental diets for 62 days on a restricted feeding regime (4–5.5% biomass/day). The group fed the full-fat fish meal diet had faster growth and a lower feed conversion ratio than the defatted fish meal diet groups after 31 and 62 days of feeding. The growth rate and feed conversion ratios of fish were significantly different between the FAEE-containing diet groups in the first 31 days of feeding, but were not significant from 32 to 62 days of feeding. Fatty acid analysis showed similarity between the fatty acid profiles in experimental diets and in fish muscle and liver tissues at the end of the experiment (all groups mean weight ~3.6 g/fish). Satiation feed intake for a single day was measured at 31 days of feeding, and feed intake was higher in the 100% FAEE diet than the control (8.3 ± 1.1% vs 6.4 ± 0.3% daily satiation ratio). This result suggests that FAEE has a positive effect on voluntary feed intake. Histological analysis of posterior intestine enterocytes and hepatocytes showed a significant reduction in lipid vacuole size in the 100% FAEE group, relative to the defatted and full-fat fish meal control groups. These results suggest that rainbow trout had utilized diet with ≥50% FAEE less efficiently in the first feeding phase, likely due to reduced fatty acid absorption, but that these trends were diminished as fish grew to a larger size. • Test diets were created using Alaskan pollock oil and/or fatty acid ethyl ester (FAEE) oil with analogous fatty acid levels. • Voluntary feeding was greater in the 100% FAEE diet than the control diet (8.3 ± 1.1% vs 6.4 ± 0.3% daily satiation ratio). • Liver and posterior intestine histology results suggest that FAEE oil is not absorbed as efficiently as Alaskan pollock oil. • Up to 25% of fish oil can be replaced with FAEE oil in trout starter feeds without significantly effecting growth rates. [ABSTRACT FROM AUTHOR]