Semi-purified Diets Research Articles

Influence of dietary zinc on growth, zinc bioaccumulation and expression of genes involved in antioxidant and innate immune in juvenile mud crabs (Scylla paramamosain).

The aim of the present study was to investigate the effects of dietary Zn level on growth performance, Zn bioaccumulation, antioxidant capacity and innate immunity in juvenile mud crabs (Scylla paramamosain). Six semi-purified diets were formulated to contain dietary Zn levels of 44·5, 56·9, 68·5, 97·3, 155·6 or 254·7 mg/kg. Dietary Zn level significantly influenced percentage weight gain (PWG), with the highest observed in crabs fed the diet containing 97·3 mg/kg Zn. Tissue Zn concentrations significantly increased as dietary Zn levels increased from 44·5 to 254·7 mg/kg. Retention of Zn in hepatopancreas increased with dietary Zn levels up to 68·5 mg/kg and then significantly decreased. Moreover, inadequate dietary Zn (44·5 and 56·9 mg/kg) reduced antioxidation markers including total superoxide dismutase (SOD) and Cu/Zn SOD activities and total antioxidant level. Crabs fed the diet with 44·5 mg/kg Zn also showed significantly lower expression of genes involved in antioxidant status, such as Cu/Zn SOD, glutathione peroxidase, catalase and thioredoxin than those fed diets containing 68·5 and 97·3 mg/kg Zn. The highest activities of phenoloxidase and alkaline phosphatase were recorded in crabs fed the diets containing 68·5 and 97·3 mg/kg Zn. Expression levels of prophenoloxidase and toll-like receptor 2 were higher in crabs fed the 97·3 mg/kg Zn diet compared with crabs fed the other diets. Based on PWG alone, the optimal dietary Zn level was estimated to be 82·9 mg/kg, with 68·5 to 97·3 mg/kg recommended for maintaining optimal Zn bioaccumulation, oxidation resistance and innate immune response of juvenile mud crabs.

Evaluation of energy and amino acids of brown rice and its effects on laying performance and egg quality of layers.

Two experiments were conducted to determine apparent metabolizable energy (AME), nitrogen-corrected AME (AMEn), and ileal digestible amino acid (AA) content of brown rice (BR) and to investigate the effect of dietary supplementation of BR on laying performance and egg quality of laying hens. In Exp. 1, 72 Hy-line Brown layers (49-week-old) were allocated to two treatments using a completely randomized block design, and each treatment included six cages per treatment and six hens per cage. A semi-purified diet was formulated to include BR as the sole source of AA and energy and an N-free diet was used to determine basal endogenous loss of AA. The hens were fed a commercial layer diet for adaptation to the experimental environment and diet for 7 days from d 0, and then fed experimental diets for 5 days from d 7. Excreta were collected from d 10 to 11 and ileal digesta were collected on d 12. On a dry matter (DM) basis, the AME and AMEn of BR was determined at 3,773 and 3,729 kcal/kg, respectively. The apparent ileal digestibility (AID) of BR ranged from 32.7% for Thr to 73.7% for Arg. The range of the standardized ileal digestibility (SID) value was between 79.4% for Met and 96.6% for Lys. In Exp. 2, 252 Hy-line Brown layers (44-week-old) were divided into four groups, comprising seven replicates of nine birds each and assigned to four experimental diets containing 0 (Control), 5%, 10%, or 15% BR for 5 weeks. The BR-containing diets were formulated to be equal in the content of AMEn and digestible AA to those of the diet without BR. No significant differences were observed in laying performances. Egg quality and blood profiles were not linearly or quadratically affected by dietary treatments. These results suggest that up to 15% BR can be included into layer feed without any adverse effects on laying performance and egg quality, if its energy and digestible AA values are well evaluated.

Effect of soybean antigenic protein on feed palatability of fishmeal replaced diets for obscure puffer (Takifugu fasciatus) and the alternation of diet preference by domestication

Ingredient Y-maze choice test, feed intake test and rare earth elements trace test were conducted in obscure puffer (Takifugu fasciatus) to study whether soybean antigenic protein would affect diet palatability when fishmeal was partially replaced by soybean products. Another eight-week domestication trial was conducted to research the possible alternation of such diet preference. In Y-maze test, both aqueous and ethanol solutions of five ingredients (fishmeal, soybean meal, fermented soybean meal, casein, and antigenic protein) were used to study the ingredient preference. Four practical diets (FMH-diet with high fishmeal, FML-diet with low fishmeal, FMLF-diet with 18.56% fishmeal replaced by fermented soybean meal, FMLS-diet with 18.56% fishmeal replaced by soybean meal) and four semi-purified diets (AP0, AP5, AP8, AP12.5) containing corresponding levels of soybean antigenic protein) were all or partially used in feed intake test and rare earth elements trace test. The results showed that the ingredient preference differed with aqueous solutions and ethanol solutions. Feed intake ratio of FMLF was significantly higher than FMH and least in FMLS, AP0 was significantly higher than AP12.5 for undomesticated fish. In rare earth element trace test, before domestication, puffer showed higher preferences of FML than FMLF and FMH and least in FMLS; after 8-week-domestication, all groups showed higher preferences to FMLS than FML and FMLF, least in FMH. In semi-purified diet groups, before domestication, the preference decreased as dietary antigenic protein increase; after domestication, all groups showed higher preferences to AP8 and least in AP12.5. These indicated that undomesticated obscure puffer had higher preference to fermented soybean meal than soybean meal. Antigenic protein might be contributed to such preference, and domestication increased the preference of puffer to diet containing 8% soybean antigenic protein. Thus, domestication can be a potential method to improve the acceptance of puffer to diet with fishmeal replaced by soybean products.

Short-term determination and long-term evaluation of the dietary methionine requirement in adult dogs.

Methionine, an essential sulphur-containing amino acid (SAA), plays an integral role in many metabolic processes. Evidence for the methionine requirements of adult dogs is limited, and we employed the indicator amino acid oxidation (IAAO) method to estimate dietary methionine requirements in Labrador retrievers (n 21). Using semi-purified diets, the mean requirement was 0·55 (95 % CI 0·41, 0·71) g/4184 kJ. In a subsequent parallel design study, three groups of adult Labrador retrievers (n 52) were fed semi-purified diets with 0·55 g/4184 kJ (test diet 1), 0·71 g/4184 kJ (test diet 2) or 1·37 g/4184 kJ (control diet) of methionine for 32 weeks to assess the long-term consequences of feeding. The total SAA content (2·68 g/4184 kJ) was maintained through dietary supplementation of cystine. Plasma methionine did not decrease in test group and increased significantly on test diet 1 in weeks 8 and 16 compared with control. Reducing dietary methionine did not have a significant effect on whole blood, plasma or urinary taurine or plasma N-terminal pro B-type natriuretic peptide. Significant effects in both test diets were observed for cholesterol, betaine and dimethylglycine. In conclusion, feeding methionine at the IAAO-estimated mean was sufficient to maintain plasma methionine over 32 weeks when total SAA was maintained. However, choline oxidation may have increased to support plasma methionine and have additional consequences for lipid metabolism. While the IAAO can be employed to assess essential amino acid requirements, such as methionine in the dog using semi-purified diets, further work is required to establish safe levels for commercial diet formats.

Effects of different dietary lipid sources on fatty acid composition and gene expression in common carp

The effects of fatty acid composition in artificial feed on the change in the fatty acid composition of carp muscles and the relationship between Δ6-Fad and Elovl5 genes participating in the regulation of fatty acid synthesis were studied. Juveniles were fed three semi-purified diets (D1–D3) for 6 weeks with different lipid sources: D1, fish oil with high highly unsaturated fatty acids (HUFA); D2, corn oil with high linoleic acid (18:2n-6, LA), D3, linseed oil with high α-linolenic acid (18:3n-3, LNA); then, samples were taken to explore the molecular mechanism and the factors which affect the synthesis of carp HUFA. The content of LA and arachidonic acid (20:4n-6, AA) in common carp fed Diet 2 was higher than in carp receiving D3 (P < 0.05), but the contents of eicosapentaenoic acid (20:5n-3, EPA) and docosahexaenoic acid (22:6n-3, DHA) were lower than in carp fed D1 and D2 (P < 0.05). The liver transcript abundance of Δ6-Fad and Elovl5 in fish fed D2 and D3 at the end of 6 weeks was generally higher than the abundance in the initial stage and in the fish fed D1 (P < 0.05). The results suggest that the common carp can biosynthesise HUFA, and the type and content of fatty acids in feed affected not only the composition and content of fatty acids in common carp muscles, but also the Δ6-Fad and Elovl5 gene expression involved in the biosynthesis of HUFA. Feeding high levels of n-3 HUFA diet can increase the body content of EPA and DHA in common carp. The results of this research may provide a theoretical basis for choosing an appropriate source of lipid for common carp feeds.

Effects of vitamin C deficiency or excess on growth performance, anti-oxidative response and fatty acid composition of juvenile abalone Haliotis discus hannai Ino

A 240-day feeding trial was conducted to investigate the effects of dietary vitamin C on growth performance, anti-oxidative response, and fatty acid composition of juvenile abalone Haliotis discus hannai Ino (initial body weight: 0.93±0.00 g). Three semi-purified experimental diets were formulated containing 0.00, 94.52, and 9 649.58 mg/kg of vitamin C supplied as L-ascorbyl-2-monophosphate. The results show that there was no significant difference in weight gain ratio, daily increment in shell length, and survival rate among the three treatments. Adding dietary vitamin C (9 649.58 mg/kg) significantly increased the activities of superoxide dismutase (SOD), glutathine peroxidase (GPX), glitathione-S-transferase (GST), glutathione reductase (GR), alkaline phosphatase (AKP), and lysozyme in viscera (P<0.05). In muscle, activities of phenoloxidase, catalase, SOD, GST, GR, and AKP were increased in the treatment with 9 649.58 mg/kg of dietary vitamin C (P<0.05). The highest concentrations of ascorbic acid in viscera and muscle were found in the group with 9 649.58 mg/kg of dietary vitamin C (P<0.05). The contents of crude protein and crude lipid in the soft body were significantly increased in the 9 649.58 mg/kg group (P<0.05). Dietary vitamin C supplementation significantly decreased the contents of saturated fatty acids (14:0, 16:0, and 18:0), and increased the composition of 18:2n-6 and 22:6n-3 in the soft body of abalone (P<0.05). Therefore, although there were no significant effects on the growth performance, dietary vitamin C supplementation improved the anti-oxidation and immune responses, increased specific unsaturated fatty acid (i.e., 16:1, 18:1n-7, 18:1n-9, 18:2n-6 and 22:6n-3), and decreased specific saturated fatty acid (i.e., 14:0, 16:0 and 18:0) contents in the soft body of abalone.

Effects of supplemental dietary bile acids on growth, liver function and immunity of juvenile largemouth bass（Micropterus salmoides）fed high-starch diet

The present study was conducted to investigate the effects of bile acids (BAs) on the growth, liver function and immunity of the largemouth bass fed high-starch diet. The experiment set three isonitrogenous and isoenergetic semi-purified diets, LS: low-starch diet (5%), HS: high-starch diet (19%) and SB: high-starch diet with BAs (350 mg/kg diet). An 8-week feeding trial was conducted in largemouth bass of initial weight 23.69 ± 0.13 g. The results indicated that the weight gain (WG) and protein efficiency ratio (PER) of fish fed LS and SB were significantly higher than HS treatment. The superoxide dismutase (SOD) and catalase (CAT) activities of SB group were significantly increased, while malondialdehyde (MDA) content significantly reduced in liver compared with HS group. The activities of alanine aminotransferase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALP) and glucose contents in plasma of SB group were significantly lower than HS treatment, whereas the content of triglyceride (TG) and total cholesterol (TC) in plasma were significantly higher than HS treatment. Additionally, the plasma immunoglobulin count, lysozyme activity and the blood leukocyte count (WBC) in SB group were significantly higher than HS group. The results of paraffin section of liver showed the histopathological alterations were significantly reduced in the SB group compared to HS group. All in all, this study revealed that bile acids supplement could significantly improve growth performance, enhance liver function and immune ability, and alleviate stress responses of M. salmoides fed high-starch diet.

Hydrolysable Tannin Supplementation Alters Digestibility and Utilization of Dietary Protein, Lipid, and Carbohydrate in Grass Carp (Ctenopharyngodon idellus)

Tannin, an antinutritional component of plant proteins was fed to grass carp (Ctenopharyngodon idellus, 8. 18 ± 0.81 g) for 8 weeks to investigate their tolerance levels. Semi-purified diets (T0, T1, T2, and T3) with varying levels of hydrolysable tannin (0, 0.75, 1.25, and 1.75% respectively) were used. No significant difference was obtained in weight gain, while feed conversion ratio of T0 was significantly lower than T2. Muscle protein content of T0 and T3 were significantly higher than T2, while lipid content of T0 was significantly higher than other groups. Muscle and hepatic glycogen in T0 were significantly lower than other groups. Muscle saturated fatty acids in T3 were significantly higher than T0, and lowest in T1 and T2, while the poly-unsaturated fatty acids in T1 and T2 were higher than T0 and lowest in T3. Significant increases were obtained in trypsin and amylase activities as tannin levels increased, the lipase activity of T0 and T1 was significantly higher than T2 and T3. Activities of hepatic alanine aminotransferase and aspartate aminotransferase decreased with increasing tannin level. The total protein in serum of T2 was significantly higher than T0 and T1 and lowest in T3, whereas globulin of T2 was significantly higher than T0 and T3 and lowest in T1, while albumin of T1 was significantly higher than other groups. Urea nitrogen of T0 was significantly higher than other groups, triglyceride and total cholesterol significantly increased with tannin level and decreased in T3, significant decreases were obtained in low-density lipoprotein cholesterol and high-density lipoprotein cholesterol in T3. mRNA expression of intestinal TOR was significantly upregulated as dietary tannin increased. In hepatopancreas, the expression of glucokinase in T1 was significantly higher than T2, and lowest in T0 and T3, pyruvate kinase in T2 was significantly higher than T0 and T1 and lowest T3. The expression of lipoprotein lipase upregulated as tannin level and downregulated in T3, and fatty acid synthase downregulated as tannin level. In conclusion, grass carp could tolerate 1.75% dietary tannin without influencing growth. However, 1.25% tannin impaired digestion and metabolism of protein, decreased the deposition of lipid and promoted utilization of carbohydrate.

Dietary protein requirement of juvenile mud crab Scylla paramamosain

This experiment was carried out to investigate the optimal dietary protein levels for juvenile Scylla paramamosain. Six isoenergtic and isolipidic semi-purified diets were formulated with graded protein levels, and the final protein concentrations were 32.69%, 38.54%, 42.92%, 49.89%, 52.09% and 60.07%, respectively. Each diet was offered to triplicate groups of 28 mud crabs (initial weight 0.04 ± 0.001 g, carapace length 3.3 ± 0.05 mm) for 8 weeks. The results showed that the mud crabs fed diets with 32.69% and 60.07% protein had significantly lower survival than those in other treatments (p < .05). The juvenile mud crab consuming 42.92%, 49.89% and 52.09% dietary protein obtained significantly higher weight gain (WG) and specific growth rate (SGR) than other groups (p < .05). Crude protein content in whole body significantly increased with increasing dietary protein level (p < .05). Crabs fed diet with 49.89% had the lowest hepatic aspartate aminotransferase (AST) activity (p < .05). A relatively higher of hepatic alkaline phosphatase (AKP) activity was observed in groups with 42.92% and 49.89% protein diet (p < .05). The hepatic superoxide dismutase (SOD) activity significantly increased with dietary protein level increasing to 49.89% and leveled off thereafter (p < .05). The EcR mRNA expression level in the eyestalk slightly decreased with increasing protein level to 42.92%, and it then obviously up-regulated with dietary protein content further increasing to 52.09% (p > .05). According to the polynomial regression analysis, 47.06% dietary protein was required for juvenile S. paramamosain to obtain maximum growth rate.

Standardized ileal digestible amino acid and metabolizable energy content of wheat from different origins and the effect of exogenous xylanase on their determination in broilers

This study was conducted to determine the standardized ileal digestible amino acids (SID AA) and nitrogen-corrected apparent metabolizable energy (AMEn) contents of 6 wheats from different origins in China and incidentally to investigate the effects of exogenous xylanase addition on SID AA and AMEn determination in broiler chicks. A total of 480 chicks were divided into 48 cages of 10 birds each balanced for body weight and fed 8 types of diets in a completely randomized design (6 replicated cages per diet) from 21 to 26 d of age. The individual wheat constituted the only source of crude protein in a semi-purified experimental diet. A nitrogen-free diet was designed to estimate basal endogenous AA loss and determine the SID AA. Titanium oxide (0.3%) was used as an indigestibility marker, and nutrient digestibility and retention were determined by the substitution method. From day 24 to 26, excreta samples were collected for AMEn determination. On day 26, the birds were euthanized, and ileum contents were obtained for AA digestibility determination. Wheat from Gansu had greater (P < 0.05) SID AA contents except Lys, Thr, Phe, and Cys, with a higher (P < 0.001) AMEn (11.83 MJ/kg) than the other wheats. The SID content of mean indispensable amino acids and dispensable amino acids were 87.35% and 88.17%, respectively, and the average AMEn value of 6 wheats was 11.14 MJ/kg. Compared with the diet without xylanase, the added xylanase resulted in higher (P < 0.05) SID contents of Met, Lys, Trp, Arg, Ile, Leu, Val, Gly, Asp, Glu, Pro, and Ala; the SID AA values were raised by 1.96% (mean of all AA); and the AMEn content was significantly increased (+0.87 MJ/kg) (P < 0.05). In conclusion, origins of wheats have significant effects on SID AA and AMEn values which were positively correlated with crude protein content of wheat; exogenous xylanase addition to a wheat-based poultry diet could significantly improve SID AA and AMEn contents for broilers.

Effects of dietary rapeseed glucosinolates, sinapic acid and phytic acid on feed intake, growth performance and fish health in turbot (Psetta maxima L.)

Various antinutritional factors (ANF) present in rapeseed protein products can adversely affect the voluntary feed intake, growth performance and physiology as well as health of fish. The aim of the presented study was to evaluate which ANF is primarily responsible for the mentioned effects. Six identical semi-purified diets based on casein were produced. One unsupplemented basal diet (BD) served as control. The remaining five diets were supplemented with graded levels of glucosinolates (low = GL, high = GH), sinapic acid (low = SL, high = SH) and one level of phytic acid (PA). Diets were fed to triplicate groups of juvenile turbot (Psetta maxima L.) until apparent satiation for 50 days. Voluntary feed intake, growth performance as well as physiology of fish were investigated. Feed intake and growth performance of fish did not differ significantly (p < 0.05) between experimental groups. However, the feed conversion ratio (FCR) increased significantly due to dietary phytic acid supplementation (10 g kg−1feed). Also the protein efficiency ratio (PER) showed a strong tendency to decrease in fish fed diet PA (p = 0.0518). Furthermore no significant differences were detected among dietary treatments regarding the proximate final body composition, hepatosomatic index, splenic index and haematocrit of fish. Concentrations of the thyroidal hormones thyroxine (T4) and triiodothyronine (T3) in blood plasma were unaffected in all fish fed experimental diets. It was concluded that higher dietary levels of phytic acid, similar to commercial plant-based diets, can adversely affect nutrient utilisation in fish nutrition. Other investigated ANF did not harm fish performance significantly in applied concentrations when supplemented in a pure grade.

Dietary manganese requirement and its effects on antioxidant enzyme activities, intestinal morphology and microbiota in oriental river prawn Macrobrachium nipponense (De Haan)

Manganese (Mn) is an essential micronutrient for animals. An 8-week feeding experiment with oriental river prawn Macrobrachium nipponense was conducted to determine the effects of Mn supplementation on growth, antioxidative indices, intestinal morphology, and gut microbiota in juveniles of this species. Manganese sulfate monohydrate was added to a basal semi-purified diet at six levels: 5.4 (control), 13, 22, 34, 73 and 150 mg Mn kg−1 diet. Each diet was fed to juvenile prawns (mean weight 0.104 ± 0.003 g), twice daily to apparent satiation, in four replicates. Prawns fed the 22 mg Mn kg−1 diet achieved the highest weight gain. The Mn concentration in muscle significantly increased with increased dietary Mn supplementation, from 5.4 to 22 mg kg−1 diet, but leveled off in animals fed greater levels. Prawns fed the 34 mg Mn kg−1 diet had the lowest malondialdehyde content. Total superoxide dismutase activity in the hepatopancreas increased significantly with an increasing level of dietary Mn in the groups fed the 5.4 (control) to 73 mg kg−1 diets, but plateaued with higher levels of supplementation. Prawns fed the 13–150 mg Mn kg−1 diets had significantly higher Mn superoxide dismutase activity than those fed the 5.4 mg kg−1 diet. Epithelial cells of the intestine were closely arranged, with clear cell definition, in the groups fed the 5.4 (control) or 22 mg Mn kg−1 diet, whereas these cells were completely separated from the basement membrane in prawns fed the 150 mg Mn kg−1 diet. The estimator of community richness (Chao1) in the intestine was significantly higher for prawns fed the 22 mg Mn kg−1 diet as compared with animals fed the 5.4 (control) and 150 mg Mn kg−1 diets. The dominant phyla in the gut of M. nipponense were Proteobacteria, followed by Firmicutes and Bacteroidetes, regardless of the level of Mn supplementation. The intestinal microbiota phylotypes significantly differed among the groups fed the 5.4 (control), 22 and 150 mg Mn kg−1 diets. We conclude that Mn supplementation in formulated feeds for this species can improve growth performance and Mn deposition in muscle, whereas diets causing Mn deficiency or excess will induce oxidant stress, and very high levels of dietary Mn could damage the intestinal morphology. The intestinal core microbiota were not affected by the dietary Mn level, although the microbiota richness was somewhat affected. Based on weight gain, the optimal level of Mn supplementation for juvenile M. nipponense is 17.59 mg kg−1 diet.

Effect of Diet Supplemented With Rapeseed Meal or Hydrolysable Tannins on the Growth, Nutrition, and Intestinal Microbiota in Grass Carp (Ctenopharyngodon idellus)

Grass carp (Ctenopharyngodon idellus; n = 320) were received four different diets for 56 days. The experimental diets were: fishmeal (FM) containing 10% fishmeal (without rapeseed meal), and rapeseed meal (RM) containing 50% rapeseed meal (without fishmeal), and two semi-purified diets either without (T0) or with 1.25% (T1) supplemental hydrolysable tannin. The approximate content of tannin in the RM diet was 1.31%, which was close to that of T1, while the tannin content of FM was close to that of T0. The weight gain rate of grass carp of the RM group was significantly lower than that of the FM group, while the feeding conversion ratio and the feeding rate were significantly higher in the T1 group than in T0. The muscle lipid content was significantly lower in RM than in FM, while T1 was lower than T0. Intestinal activities of trypsin and α-amylase were significantly higher in T1 and RM groups compared with the other treatments. The hepatic activities of aspartate aminotransferase and alanine aminotransferase were lower in T1 and RM groups compared with the other treatments, while hepatic glycogen, and malonaldehyde were significantly higher in T1 and RM groups. In serum, the total protein and globulin contents were significantly higher in T1 and RM groups, while albumin was significantly lower in the RM group compared to the FM group. High-throughput sequencing showed that Proteobacteria, Firmicutes, and Actinobacteria were the dominant bacterial phyla among groups. The intestinal microbial diversity was higher in T1 and RM. Redundancy analysis showed that tannin, rapeseed meal, and intestinal trypsin activity were positively or negatively correlated with the relative abundance of several different intestinal microbiota at phylum and/or genus levels. The results indicated that 1.25% tannin could not be the main reason for the poor growth of grass carp of the RM group; however, the protein metabolism was disturbed, the absorption of carbohydrate was improved, and the accumulation of lipid had decreased. Furthermore, tannin and rapeseed meal supplementations modulated the intestinal microbiota, and may sequentially regulate the intestinal function by fermenting dietary nutrition, producing digestive enzymes, and modulating probiotics.

High dietary lipid level alters the growth, hepatic metabolism enzyme, and anti-oxidative capacity in juvenile largemouth bass Micropterus salmoides.

The present study was conducted to investigate the effects of high dietary lipid levels on growth, metabolism, antioxidant capacity, and immune responses of largemouth bass. Fish (initial body weight 13.38 ± 0.11g) were fed three isonitrogenous semi-purified diets containing 5%, 10%, and 20% lipid, respectively. The results indicated that fish fed 10% lipid diet showed significantly better final body weight, specific growth rate (SGR), protein efficiency ratio (PER), and feed conversion ratio (FCR) compared with that fed 5% lipid diet. Meanwhile, fish fed 20% lipid diet had a significantly higher viscera ratio (VR), hepatosomatic index (HSI), intraperitoneal fat ratio (IPF), and liver lipid content than those fed the other diets. Higher alanine aminotransferase (ALT) and aspartate transaminase (AST) activities, total cholesterol (TC), triglyceride (TG), free fatty acids (FFA), high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C) contents, and LDL-C/HDL-C value in plasma were recorded in fish fed 20% lipid diet, while higher insulin contents were obtained in fish fed 5% lipid diet. In addition, the highest carnitine palmitoyltransferase I (CPT1), AMP-activated protein kinase (AMPK), fructose-1,6-bisphosphatase (FBPase), and phosphoenolpyruvate carboxykinase (PEPCK) activities in the liver were also observed in fish fed 20% lipid diet. However, fish fed 20% lipid diet had a significantly lower superoxide dismutase (SOD) and catalase (CAT) activities and higher MDA contents in liver than those fed the other diets. The higher nitric oxide (NO) contents and inducible nitric oxide synthase (iNOS) activity in liver were recorded in fish fed 10% lipid diet. Moreover, the alkaline phosphatase (ALP), inducible nitric oxide synthase (iNOS) and lysozyme activities, and nitric oxide (NO) contents in plasma were higher in fish fed the 10% diets than the other groups. In conclusion, high dietary lipid levels could suppress growth performance and liver anti-oxidative capacity, and reduce immune responses of largemouth bass.

Additivity of apparent and standardized ileal amino acid digestibility of corn and soybean meal in broiler diets.

A total of 144 male Ross 308 broiler chickens were used in a digestibility bioassay to determine the additivity of apparent or standardized amino acid (AA) digestibility values for corn, soybean meal (SBM), or a mixture of corn and SBM. Following the receipt of a standard commercial starter diet from days 1 to 21, broilers were divided into 4 treatments (6 cages per treatment; 6 birds per cage) and received semi-purified diets based on corn, SBM, or a mixture of corn and SBM or a nitrogen-free diet (for the estimation of basal endogenous AA losses). Apparent and standardized ileal AA digestibility values were determined on day 28 and the measured values for the mixture of corn and SBM were statistically compared to calculated values based on the digestibility of the individual raw materials and their concentration in the mixed diet. The use of apparent ileal AA digestibility values for single ingredients resulted in an underestimation (P < 0.05) of the digestibility of the mixed feed for nitrogen, Lys, Arg, Thr, Asp, and Gly. Correction of apparent digestibility values to standardized values entirely corrected the underestimation in the mixed feed and resulted in a predictable linearity from single ingredients to the mixed diet. It can be concluded that standardized ileal AA digestibility values are more additive than apparent values and should be used, where possible, to enhance the accuracy of feed formulation and reduce both the diet cost and the environmental impact of nitrogenous pollution.

Evaluation of dietary protein requirement for the growth performance of minor carp,Cirrhinus reba(Hamilton, 1822) fingerlings

An experiment was designed to evaluate the requirement of dietary protein for Reba carp, Cirrhinus reba fingerlings using semi-purified diet. Five isocaloric diets were prepared containing 20%, 25%, 30%, 35% and 40% level of protein using casein, gelatin as a major protein source. The experiment was conducted for 105 days in triplicates to evaluate the growth, survival, feed utilization, carcass composition of C. reba. Mean weight gain was highest (p < .05) in T3. Specific growth rate was highest in T3 and lowest in T1. Similarly, significantly (p < .05) highest net fish yield were recorded in T3. No significant difference was recorded in survivability. Feed conversion ratio, protein efficiency ratio, feed conversion efficiency and protein conversion efficiency were significantly (p < .05) higher for T3 compared with other treatments. Highest carcass protein and lipid values were recorded in T3. So, conclusion can be drawn that 30% crude protein is optimum for overall performance. Furthermore, broken-line analysis for specific growth rate, final biomass and net fish yield indicated that dietary protein level of 28.148 to 28.253% is optimum for the best growth performance of fingerling C. reba.

In vivo digestion characteristics of protein sources fed to broilers

The rate and extent of protein digestion are relevant to broiler performance and health, but information is lacking on the rate of digestion and the characteristics of the undigested fraction for common protein feed ingredients. Therefore, this study evaluated the digestion kinetics and the distal ileum (DI) digesta protein characteristics of protein meals fed to broiler chickens. Using a completely randomized design, 360 male broilers at 14 D of age were assigned to 60 battery cages and fed semi-purified diets composed of wheat starch (N-free) or wheat starch with either corn distillers dried grains with solubles (CDDGS), corn gluten meal, meat and bone meal, soybean meal, fish meal (FM), porcine meal (PCM), canola meal, blood meal (BM), or feather meal. At day 21, the protein digestion kinetics and total and soluble protein of the DI content were determined. Differences were considered significant when P ≤ 0.05. Protein source affected the extent of amino acid (AA) and CP digestibility at the DI. The results demonstrated differences in digesta mean retention time (MRT) and the rate of digestion of AA and CP among protein sources. FM had the shortest MRT of 46min, whereas CDDGS had the longest at 142min. Both FM and PCM had the highest digestion rates for most of the AA evaluated among the protein sources, whereas CDDGS had the lowest. In turn, the total and soluble CP in the distal ileal contents ranged from 54 to 1466 mg and 6 to 347mg, respectively. In conclusion, dietary protein source influences the amount and solubility of the undigested protein in the DI and the digestion kinetics of AA and CP along the small intestine of broilers. These parameters may contribute to the effects of protein source on muscle deposition and could influence the impact protein sources may have on gut health through protein fermentation.

118 Digestibility of amino acids in hydrolyzed feather meal, flash dried poultry protein, poultry meal, and meat and bone meal fed to broiler chickens and pigs

Abstract This study was conducted to determine the standardized ileal digestibility (SID) of amino acids (AA) in hydrolyzed feather meal (HFM), flash dried poultry protein (FDPP), poultry meal (PM), and meat and bone meal (MBM) fed to broiler chickens and pigs. Four semi-purified diets and a nitrogen-free diet were prepared. Exp. 1 was conducted with 416 male broiler chickens (initial body weight [BW] = 705 ± 100.0 g) at d 18 post-hatching in a randomized complete block design. Birds were fed diets for 5 d and then euthanized to collect ileal digesta. In Exp. 2, ten barrows (initial BW = 22.1 ± 1.59 kg) surgically fitted with T-cannulas at the distal ileum were assigned to duplicate 5 × 4 incomplete Latin square design with 5 diets and 4 periods. There were 5-d adaptation and 2-d ileal digesta collection periods in each experimental period. Data were analyzed as a 2 × 4 factorial arrangement with the effects of species (i.e., broiler chickens and pigs) and four experimental diets. There were interactions (P &lt; 0.05) in the SID of His, Lys, Thr, Trp, and Val between diets and species. In broiler chickens, the SID of Lys in MBM was greater (P &lt; 0.05) than HFM and FDPP but was not different from PM. Pigs fed MBM had greater (P &lt; 0.05) SID of Lys than HFM, FDPP, and PM. In broiler chickens, the SID of His, Thr, and Trp in FDPP and PM were greater (P &lt; 0.05) than HFM but was less (P &lt; 0.05) than MBM. In pigs, the SID of His, Thr, and Trp in FDPP and PM were greater (P &lt; 0.05) than HFM but was not different from MBM. In conclusion, differences in the SID of AA among animal protein sources were affected by species of monogastric animals.

Protein quality in experimental diets and amino acid digestibility

Abstract Digestibility of AA in feed ingredients for pigs has been generally determined by feeding semipurified diets containing test ingredients as a sole source of nitrogen. However, malnutrition caused by feeding semi-purified diets may affect the digestibility of AA. Therefore, the hypothesis of this study was that the standardized ileal digestibility (SID) of AA in distillers’ dried grains with solubles (DDGS) are not affected by the addition of casein in experimental diets. In Exp. 1, 20 growing pigs were allotted to dietary treatments including 2 diets containing either 480 g/kg DDGS or 308 g/kg DDGS and 60 g/kg casein. The SID of Lys and Phe for DDGS in the diet containing casein were greater (P &lt; 0.05) than those without casein. Exp. 2 was conducted with 20 growing pigs assigned to dietary treatments containing 0, 55, 110, or 165 g/kg casein while the concentration of DDGS decreased at 466.8, 311.2, 155.6, or 0 g/kg. The SID of most indispensable AA in DDGS linearly (P &lt; 0.05) decreased with increasing concentration of casein. Experiment 3 was conducted to verify that the results of Exp. 1 were affected by the addition of casein or by the concentration of DDGS or both. Twenty growing pigs were assigned to dietary treatments prepared as a 2 × 2 factorial arrangement with the concentration of DDGS at 466.8 or 155.6 g/kg and casein at 0 or 110 g/kg. The SID of most indispensable AA in DDGS at 466.8 g/kg were greater (P &lt; 0.01) than in DDGS at 155.6 g/kg regardless of dietary casein. Overall, the addition of 60 g/kg casein to experimental diets may increase the SID of AA in low-protein quality ingredients but the addition of higher concentration of casein and low concentration of dietary protein from test ingredients may decrease the SID of AA.

Hippuric acid and 3-(3-hydroxyphenyl) propionic acid inhibit murine osteoclastogenesis through RANKL-RANK independent pathway.

Nutritional factors influence bone development. Previous studies demonstrated that bone mass significantly increased with suppressed bone resorption in early life of rats fed with AIN‐93G semi‐purified diets supplemented with 10% whole blueberry (BB) powder for 2 weeks. However, the effects of increased phenolic acids in animal serum due to this diet on bone and bone resorption were unclear. This in vitro and in ex vivo study examined the effects of phenolic hippuric acid (HA) and 3‐(3‐hydroxyphenyl) propionic acid (3‐3‐PPA) on osteoclastic cell differentiation and bone resorption. We cultured murine osteoclast (macrophage) cell line, RAW 264.7 cells, and hematopoietic osteoclast progenitor cells (isolated from 4‐week‐old C57BL6/J mice) with 50 ng/ml of receptor activator of nuclear factor κ‐Β ligand (RANKL). Morphologic studies showed decreased osteoclast number with treatment of 2.5% mouse serum from BB diet–fed animals compared with those treated with serum from standard casein diet–fed mice in both RAW 264.7 cell and primary cell cultures. HA and 3‐3‐PPA, but not 3–4‐PPA, had dose‐dependent suppressive effects on osteoclastogenesis and osteoclast resorptive activity in Corning osteo‐assay plates. Signaling pathway analysis showed that after pretreatment with HA or 3‐3‐PPA, RANKL‐stimulated increase of osteoclastogenic markers, such as nuclear factor of activated T‐cells, cytoplasmic 1 and matrix metallopeptidase 9 gene/protein expression were blunted. Inhibitory effects of HA and 3‐3‐PPA on osteoclastogenesis utilized RANKL/RANK independent mediators. The study revealed that HA and 3‐3‐PPA significantly inhibited osteoclastogenesis and bone osteoclastic resorptive activity.