Levels Of Dietary Vitamin Research Articles

Effects of Dietary Levels of Vitamin E on Broiler Breeder Performance

Effects of Dietary Levels of Vitamin E on Broiler Breeder Performance

Hematoimmunological responses of juvenile Nile tilapia (Oreochromis niloticus) receiving the dietary supplementation of immunomodulators and different levels of vitamins after challenge with physical stress.

In this study, we analyzed the hematoimmunological effects of dietary supplementation with immunomodulators (β-glucans + nucleotides) and different levels of vitamins on Nile tilapia (Oreochromis niloticus) after exposure to physical stress. The following four diet treatments were used: diets with indicated vitamin levels (Vitind), diets with Vitind + immunomodulator (Vitind + Immune), diets with high vitamin content (Vithigh), and those with Vithigh + immunomodulator (Vithigh + Immune). The experiment included 560 fish in 28 tanks (20 fish tank-1), with seven replicates per treatment. After 60 days of supplementation, the water temperature was set at 20 °C, and complete biometrics were performed. The animals were then subjected to physical stress with temperature oscillations of 20 ºC to 30 ºC/30 ºC to 20 ºC/20 ºC to 30 ºC. Hematoimmunological data from 140 animals were collected post-stress. Antimicrobial titer and total plasma protein levels were significantly higher in fish not receiving immunomodulator-supplemented diets (2.88 ± 0.43 log2 and 26.81 ± 4.01 mg∙mL-1, respectively) than in those that did. Conversely, the agglutination titer increased in fish fed with lower vitamin levels (3.33 ± 0.66 log2) compared to those with higher vitamin levels. Increased immunoglobulin levels were observed in fish fed diets co-supplemented with vitamins and immunomodulators, revealing an interaction between immunomodulators and dietary vitamin levels. In summary, the inclusion of immunomodulators in the diet enhanced the animals' resistance to physical stress and improved hematoimmunological parameters. Additionally, a high vitamin content in the diet did not modulate the immune responses in the animals.

Comparing the effects of two different vitamin regimens on bone metabolism for meat ducks at starting phase

Objective Leg problems including lameness and tibial dyschondroplasia (TD) are one of the most important factors affecting health and animal welfare in meat-type poultry, which are considerably impacted by dietary vitamin regimens. The present study was conducted to investigate the effects of dietary vitamin levels on growth performance and tibia quality in 14-d-old meat ducks. Methods One-d-old Cherry Valley meat-type male ducks were allocated to two vitamin regimens for 14 d, which was formulated according to the recommendation of the National Research Council (NRC, 1994) or China Agricultural Industry Standards (NY/T 2122-2012). Each group included 8 replicates with 16 birds per replicate. Results There was no significant difference in the growth performance of ducks, whereas dietary NY/T vitamin supplementation decreased leg abnormalities as compared to the NRC group, along with similar tibia length, perimeter, and the relative weight of tibia. The tibia from the birds that received the NY/T vitamin diet exhibited markedly higher (p < 0.05) ash level, calcium (Ca) content, and bone strength when compared with the bone of NRC vitamin-treated birds. In the tibia proximal end, the increased trabecular area and a number of bone trabeculae were observed in the NY/T vitamin diet (p < 0.05). Moreover, a pronounced increase (p < 0.05) in the serum Ca, alkaline phosphatase activity, and C-terminal cross-linked telopeptide of type I collagen level as the indicators of bone formation were found in NT/T vitamin diet than them in NRC diet. Dietary supplementation with NY/T vitamin regimen also significantly upregulated the relative gene expression of phosphate regulating endopeptidase homolog x linked (Phex), an osteoblastic gene, as compared to the NRC vitamin diet (p < 0.05). However, the concentration of serum bone resorption markers and the transcription of osteoclast-related genes were comparable between the NRC and NY/T vitamin groups (p > 0.05). Conclusion NY/T vitamin diet improved tibia quality and subsequently decreased leg abnormalities in 14-d-old ducks, which was probably linked with the promoted bone formation.

Deficiency and excess in dietary vitamin K3 negatively affect gilthead seabream (Sparus aurata) larvae performance and bone health

Despite the importance of vitamin K to maintaining normal growth, survival, and bone health in fish, studies on the effect of different dietary levels of vitamin K on marine fish larvae are very scarce. In the present study, the effect of vitamin K on growth performance, incidence of bone anomalies, bone mineralization, and expression of bone biomarkers were investigated in gilthead seabream larvae by feeding microdiets with six different levels of vitamin K3 (1.32, 1.63, 4.98, 12.26, 22.90, and 58.51 mg kg−1) for 14 days. The highest total length and body weight were registered in larvae fed 4.98 mg kg−1 vitamin K3, whereas the further increase in dietary vitamin K3 up to 22.9 and 58.51 mg kg−1 reduced growth and survival. The highest incidence of anomalies in branchiostegal rays, glossohyal, or neurocranium bones was found in larvae fed the lowest vitamin K3 level (1.32 mg kg−1), whereas the increase in vitamin K3 reduced these anomalies following potential regressions with inflection points close to 5 mg kg−1 vitamin K3. However, larvae fed the highest vitamin K3 levels (22.9 and 58.51 mg kg−1) showed a high incidence of abdominal kyphosis, reduced mineralization, and unbalances in the expression of bone health-related genes. In conclusion, the present study suggested an optimum dietary level of 5 mg kg−1 of vitamin K3 to promote seabream larval growth and reduce the incidence of bone anomalies. On the contrary, the elevation of dietary vitamin K3 levels up to 22.9 and 58.51 mg kg−1 has a deleterious effect on larval performance and bone health.

Evaluating the American Urologic Association (AUA) dietary recommendations for kidney stone management using the National Health And Nutritional Examination Survey (NHANES).

The objective of this study is to evaluate the conventional dietary recommendations for stone prevention among patients in the National Health and Nutritional Examination Survey (NHANES) and compare dietary components and special diets between stone formers and non-stone formers. We analyzed the NHANES 2011-2018 dietary and kidney condition questionnaires, among 16,939 respondents who were included in this analysis. Dietary variables were selected based on the American Urological Association (AUA) guideline for Medical Management of Kidney Stones and from other studies on kidney stone prevention. Weighted multivariate logistic regression models were used to assess the relationship of dietary food components (categorized into quartiles) and dietary recommendations with kidney stone formation (yes vs no), adjusted for total caloric intake, comorbidities, age, race/ethnicity, and sex. The prevalence of kidney stones was 9.9%. Our results showed association of kidney stones with lower levels of potassium (p for trend = 0.047), which was strongest for < 2000mg (OR = 1.35; 95% CI 1.01-1.79). Higher vitamin C intake was inversely associated with stone formation (p for trend = 0.012), particularly at daily intake levels between 60 and 110mg (OR = 0.76; 95% CI 0.60-0.95) and above 110mcg (OR = 0.80; 95% CI 0.66-0.97). There were no associations between other dietary components and kidney stone formation. Higher levels of dietary vitamin C and potassium intake may be indicated for stone prevention and warrants further investigation.

The Dietary Requirement of Juvenile Grass Shrimp (Penaeus monodon) for Vitamin D ,

Two 8-wk experiments were conducted to determine the adequate level of dietary vitamin D for juvenile grass shrimp (Penaeus monodon). In Experiment 1, purified diets with six levels (0, 0.1, 0.5, 2.5, 12.5 and 62.5 mg/kg diet) of supplemental ergocalciferol and cholecalciferol were fed to P. monodon (mean weight 0.19 +/- 0.02 g). In Experiment 2, we used 0, 0.05, 0.1, 0.2, 0.3, 0.6 and 1.0 mg/kg of supplemental cholecalciferol in basal diet fed to the shrimp (mean weight 0.25 +/- 0.03 g). In both experiments, shrimp fed vitamin D-deficient diets grew poorly. In Experiment 1, poorer growth performance was observed in shrimp fed diets containing ergocalciferol compared with those fed the diets containing cholecalciferol. In Experiment 2, weight gain was highest in shrimp fed the diet supplemented with 0.2 mg cholecalciferol/kg diet, followed by the groups fed 0.1 mg/kg, then 0.3 mg/kg, 0.05 and 0.6 mg/kg, 1.0 mg/kg, and finally the unsupplemented control group. The differences among these groups were significant (P < 0.05). The feed efficiency ratio and alkaline phosphatase activity generally followed the same pattern as the weight gain. Analysis by brokenline regression of weight gain and alkaline phosphatase activity of the shrimp in Experiment 2 indicated that the adequate dietary cholecalciferol concentration for growing P. monodon is approximately 0.1 mg/kg.

Dietary 25-hydroxy-cholecalciferol and additional vitamin E improve bone development and antioxidant capacity in high-density stocking broilers.

This study aimed to investigate the effects of diets supplemented with 25-hydroxycholecalciferol [25-(OH)D3] and additional vitamin E on growth performance, antioxidant capacity, bone development, and carcass characteristics at different stocking densities on commercial broiler farms. A total of 118,800 one-day-old Arbor Acres broilers were assigned to a 2 × 2 factorial treatment consisting of two dietary vitamin levels (5,500 IU vitamin D3 and 60 IU vitamin E: normal diet, using half 25-(OH)D3 as a source of vitamin D3 and an additional 60 IU of vitamin E: 25-(OH)D3+VE diet) and two stocking densities (high density of 20 chickens/m2: HD and 16 chickens/m2: LD). The experiment lasted for 42 d. The results showed that high-density stocking negatively affected the growth performance of broilers during the first four weeks, whereas the vitamin diet treatment significantly improved the feed conversion ratios (FCR) during the last 2 wk. Vitamin diets increased catalase at 14 and 42 d, and the glutathione peroxidase (GSH-px) levels at 42 d in high-density-stocked broilers. The interaction showed that serum vitamin E levels were significantly improved at 28 d of age in high-density-stocked broilers as a result of the vitamin diets. Stocking density and dietary treatments were found to significantly affect bone development, with the vitamin diet significantly increasing metatarsal length and femoral bone strength in broilers from high-density stocking density at 28 d of age. High stocking density increased the proportion of leg muscles and meat yield per square meter. In general, 25-(OH)D3 and additional vitamin E suppressed oxidative stress and ameliorated the negative effects of high-density stocking on bone development in a commercial chicken farm setting. Vitamin diets improved the FCR of broilers, while high-density stocking resulted in better economic outcomes.

Effects of graded levels of dietary vitamin a supplementation on reproductive performance in geese

Wan, X.L., Zheng, X.C., Dai, H., Liang, J.R., Yang, H.M. and Wang, Z.Y. 2023. Effects of graded levels of dietary vitamin A supplementation on reproductive performance in geese. Animal Nutrition and Feed Technology, 23: 77–86.

Effect of Supplementation of Vitamin A on Growth, Haemato-Biochemical Composition, and Antioxidant Ability in Cyprinus carpio var. communis.

Vitamin A requirement in fingerling common carp, Cyprinus carpio var. communis (1.64 ± 0.02 g; ABW ± SD), was evaluated by conducting a 10 week growth experiment. Casein-gelatin-based test diets representing six graded levels of vitamin A (0, 0.03, 0.07, 0.11, 0.15, and 0.19 g/kg, dry diet) were designed and fed to the triplicate group of fish at 08:00 and 16:00 hrs at the rate of 4% body weight per day. Growth parameters like live weight gain (LWG %), feed conversion ratio (FCR), protein efficiency ratio (PER), specific growth rate (SGR), and body protein deposition (BPD) improved significantly (P < 0.05) with each elevated dietary vitamin A level and found maximum growth rate along with the best- FCR at 0.11 g/kg diet. Dietary vitamin A levels also significantly (P < 0.05) affected haematological parameters of the fish. Highest haemoglobin (Hb), erythrocyte count (RBC), haematocrit content (Hct %), and lowest leucocyte count (WBC) were observed at 0.11 g/kg vitamin A fed diet compared to all the diets. Highest protein and lowest fat content were observed in the group of fingerlings fed with 0.11 g/kg vitamin A containing diet. Blood and serum profile also showed some significant (P < 0.05) differences with elevating concentration of dietary vitamin A levels. Serum parameters like aspartate aminotransferase (AST), alanine aminotransferase (ALT), and cholesterol values decreased significantly (P < 0.05) at 0.11 g/kg vitamin A fed diet compared to control diet. However, except albumin the other electrolytes improved significantly (P < 0.05) and maximal values of these parameters were also evident at 0.11 g/kg of vitamin A fed diet. Better value of TBARS was found in the group that fed 0.11 g/kg vitamin A diet. Hepatosomatic index and condition factor improved significantly (P < 0.05) with fish fed at optimal dose 0.11 g/kg of vitamin A diet. Based on quadratic regression analysis of LWG%, FCR, BPD, Hb, and calcium values of C. carpio var. communis against the varying levels of dietary vitamin A, an optimum growth, best FCR, higher BPD, Hb, and Ca values lie in the range of 0.10 to 0.12 g/kg diet, respectively. The data generated during this study would be important in developing vitamin A balanced feed for successful intensive culture of C. carpio var. communis.

Metabolic bone disease in a white‐faced saki (Pithecia pithecia)

AbstractNon‐human New World primates are recognized as particularly susceptible to metabolic bone disease. Improper UV light exposure and/or insufficient dietary levels of vitamin D can lead to poor bone development and skeletal mineralization deficits. This report documents the clinical progression of rickets, a type of metabolic bone disease, in a white‐faced saki (Pithecia pithecia), presenting the first documented case, to our knowledge, of this condition in this primate species. Because inconsistent feeding habits and seasonality are believed to have contributed to the development of rickets in this individual, adequate UV light exposure and adequate levels of dietary vitamin D are important considerations for individuals housed indoors and during periods of growth, ensuring adequate calcium regulation and prevention of sequela associated with low calcium and vitamin D levels. Through a multi‐faceted approach targeting medical, dietary, and husbandry changes, primate species exhibiting signs of metabolic bone diseases can be successfully managed to allow for a good quality of life.

Modulation of Fecal Metabolites by Heat Stress and Diet, and Their Association with Inflammation and Leaky Gut Markers in Dairy Cows.

The analysis of fecal metabolite profiles could provide novel insights into the mechanisms underlying animal responses to environmental stressors and diet. We aimed to evaluate the effects of a 14-day heat stress period and of dietary mineral and vitamin supplementation under heat stress on fecal metabolite profiles and to investigate their associations with physiological markers of heat stress, leaky gut, and inflammation in lactating dairy cows. Twelve multiparous Holstein cows (42.2 ± 5.6 kg milk/d; 83.4 ± 27.1 DIM) were enrolled in an experiment in a split-plot design. The main plot was the level of dietary vitamin E and Se, as follows: (1) low (L-ESe; 20 IU/kg vitamin E, 0.3 ppm Se) or (2) high (H-ESe 200 IU/kg vitamin E, 1.2 ppm Se). Within each plot, six cows were randomly assigned to either (1) heat stress (HS; Total Humidity Index (THI): 82), (2) pair-feeding in thermoneutrality (TNPF; THI = 64), or (3) HS with vitamin D3 and Ca supplementation (HS+DCa; 1820 IU/kg and 1.5% Ca; THI: 82) in a replicated 3 × 3 Latin square design with 14-day periods and 7-day washouts. The concentrations of 94 metabolites were determined in fecal samples, including amino acids, fatty acids, biogenic amines, and vitamins. Relative to the L-ESe group, the H-ESe group increased α-tocopherol by threefold, whereas δ-tocopherol was decreased by 78% (PFDR < 0.01). Nevertheless, correlation analysis between α-tocopherol and all the others fecal metabolites or physiological heat stress measures did not show significant associations. No interactions between main plot and treatments were observed. Relative to TNPF, HS increased plasma tumor necrosis factor-alpha (TNF-α), plasma lipopolysaccharide-binding protein (LBP), milk somatic cell counts (SCC), respiratory rates, rectal temperatures, fecal tridecylic and myristic acids, vitamin B7, and retinol, whereas it decreased fecal amino acids such as histidine, methyl histidine, acetyl ornithine, and arginine (PFDR < 0.05). In contrast, HS+DCa increased fecal methyl histidine concentrations and reduced milk SCC, plasma TNF-α, and LBP, as well as rectal temperatures. Discriminant analysis revealed fecal histidine, taurine, acetyl ornithine, arginine, β-alanine, ornithine, butyric + iso-butyric acid, plasma non-esterified fatty acids, TNF-α, LBP, C-reactive protein, and milk SCC were predictive of HS. Several metabolites were predictive of HS+DCa, although only tryptophan was discriminant relative to HS. In conclusion, both heat stress and the supplementation of vitamin D3 and Ca can influence the fecal metabolome of dairy cows experiencing heat stress, independently of dietary levels of vitamin E and Se. Our results suggest that some fecal metabolites are well associated with physiological measures of heat stress and may thus provide insights into the gut-level changes taking place under heat stress in dairy cows.

Effect of vitamin E supplementation on chicken sperm quality: A meta-analysis.

Background and Aim:Among several factors, the sperm quality of poultry is affected by the rooster’s body size and the availability of antioxidants like vitamin E. This study aimed to determine the effect of dietary vitamin E supplementation on rooster sperm quality through a meta-analysis.Materials and Methods:After verification and evaluation, a total of 19 articles were included in this study. Data, including dietary vitamin E, semen volume, concentration, total sperm cells, pH, motility, viability, percentage of dead and abnormal sperm, vitamin E sperm content, malondialdehyde (MDA) content, and testosterone levels, were tabulated in a database; these were subsequently analyzed using mixed modeling with vitamin E dose as a fixed effect and study identity as a random effect.Results:Dietary supplementation level of vitamin E significantly (p<0.001) affected sperm concentration, significantly affected motility (p<0.001), significantly affected sperm vitamin E (p<0.001), significantly affected viability (p<0.001), and significantly affected chicken sperm fertility (p=0.001). Vitamin E administration also significantly reduced the number of sperm cell deaths (p<0.001); however, increased dietary levels of vitamin E did not affect semen volume (p=0.853), pH (p=0.951), MDA (p=0.542), the percentage of abnormal sperm cells (p=0.343), nor testosterone levels (p=0.063).Conclusion:Dietary vitamin E supplementation is recommended for male chickens since it generally enhances the quality of their sperm.

Effect of Dietary Vitamin E on Growth Performance, Immunity and Antioxidant Capacity in Male Jiangnan White Goslings from 1 to 28 d of Age

This experiment aimed to investigate effects of the different dietary levels of vitamin E (VE) on the growth performance, immunity and antioxidant capacity of goslings. A total of 240 1-day-old, male Jiangnan white goslings were selected and randomly divided into 6 groups. Each treatment included five replicates. The basal diet was supplemented with 6 concentrations of VE (0, 12, 24, 36, 48 and 60 mg DL-α-tocopherol acetate/kg). The results were as follows: (1) The α-tocopherol content in the serum and liver of goslings increased linearly as supplemental VE increased in diet (p &lt; 0.05). (2) The body weight (BW) and average daily gain (ADG) increased quadratically with increasing dietary VE supplementation (p &lt; 0.05). Dietary VE supplementation could significantly reduce the feed/gain ratio (F/G) (p &lt; 0.05). (3) Dietary supplementation with VE could significantly improve the contents of immunoglobulin A (IgA) and immunoglobulin G (IgG) in the serum of the goslings (p &lt; 0.05). The content of interferon-γ (IFN-γ) in the serum was significantly reduced with VE supplementation (p &lt; 0.05). (4) Dietary supplementation with VE could significantly improve serum and liver catalase (CAT), superoxide dismutase (SOD) activities and liver total antioxidant capacity (T-AOC) (p &lt; 0.05); Serum and liver MDA contents were significantly reduced with VE supplementation (p &lt; 0.05). In summary, dietary supplementation with VE could improve growth performance, immunity and antioxidant capacity. Based on broken-line regression analysis, the dietary VE supplementation level for ADG was 12.51 mg/kg, but higher supplementation level should be considered to improve immunity and antioxidant capacity.

Nutritional feed additives reduce the adverse effects of transport stress in the immune system of Tambaqui (Colossoma macropomum)

Here we show that selected nutritional feed additives reduce the adverse effects of transport stress on the immune system and hematology of tambaqui. We formulated a control diet to contain normal dietary levels of vitamin E (21.6mg/ kg diet) and C (143mg/kg), then we added supra levels of these vitamins (vit E - 264mg/kg and vit C - 1000mg/kg) to a second diet. Finally, a third diet was produced to contain similar levels of vitamins from diet 2 with 0.1% beta-glucan supplementation. Four hundred thirty-two tambaquis (20.91g±0.27g) were randomly assigned to 12 aquaria and fed the diets for 15 days; then, all fish were transported for five h and then returned to the aquaria. Blood samples were collected before and after the transport and at the end of the trial (60 days). Transportation significantly increased blood glucose that returned to baseline levels at the end of the trial. However, cortisol seemed to be unresponsive to the stress. Surprisingly, the stress significantly increased the immunoglobulin level after transport. Additionally, the transport markedly reduced the red blood cell count and leukocyte and lymphocytes counts while increasing the control group's neutrophil number. These effects lasted until the end of the trial in the control group. Supra levels of the vitamins and glucan supplementation prevented the decrease in red blood cell and leukocyte count after the stress. Additionally, beta-glucan supplementation induced lower cortisol levels in all the sampling points. However, the effect on the immune parameters was limited, increasing only the lysozyme activity and serum protein levels in the beta-glucan supplemented group and the group fed only the supra levels of vitamins, respectively. In sum, our results indicated that transport for five h induced a limited effect on stress biomarkers. The use of supra levels of antioxidant vitamins alone or in combination with beta-glucan could restore or prevent the adverse effects of stress on hematology and the immune system.

Dietary Vitamin A and Breast Cancer Risk in Black Women: The African American Breast Cancer Epidemiology and Risk (AMBER) Consortium

BackgroundStudies in women of European descent showed an inverse association of dietary vitamin A (retinol and carotenoids) intake with breast cancer risks, mainly in premenopausal women. ObjectivesWe examined whether higher compared with lower levels of dietary vitamin A are associated with reduced breast cancer risks among Black women by estrogen receptor (ER) and menopausal statuses. MethodsIn this pooled analysis, data were from 3564 breast cancer cases and 11,843 controls (mean ages = 56.4 and 56.3 years, respectively) in the African American Breast Cancer Epidemiology and Risk (AMBER) Consortium. Dietary intake was assessed by FFQs. Multivariable logistic regressions were performed to estimate ORs and 95% CIs for study-specific quintiles of total vitamin A equivalents and individual carotenoids, and a pooled OR was estimated by a random-effect model. ResultsWe observed an inverse association of total vitamin A equivalents with ER-positive breast cancer (quintiles 5 compared with 1: pooled OR: 0.82; 95% CI: 0.67–1.00; P-trend = 0.045). The association was seen among premenopausal women (pooled OR: 0.60; 95% CI: 0.43–0.83; P-trend = 0.004), but not among postmenopausal women (pooled OR: 0.99; 95% CI: 0.77–1.28; P-trend = 0.78). Additionally, there were inverse associations of dietary β-carotene (quintiles 5 compared with 1: pooled OR: 0.70; 95% CI: 0.51–0.95; P-trend = 0.08) and lutein (pooled OR: 0.63; 95% CI: 0.45–0.87; P-trend = 0.020) with ER-positive breast cancer among premenopausal women. There was no evidence for an association of total vitamin A equivalents or individual carotenoids with ER-negative breast cancer, regardless of menopausal status. ConclusionsOur findings on dietary vitamin A and breast cancer risks in Black women are consistent with observations in women of European descent and advance the literature showing an inverse association for ER-positive disease.

Effects of dietary vitamin E on growth performance, body composition, antioxidant capacity, and some immune responses in Caspian trout (Salmo caspius)

This study was conducted to evaluate the effect of dietary vitamin E on growth performance, feed utilization, biochemical properties and some immune responses in Caspian trout, Salmo caspius. Six experimental diets were formulated with semi-purified ingredients supplemented with vitamin E in the form of DL-α-tocopherol acetate to provide the actual vitamin E concentrations of 4.9 (the basal diet), 8.6, 17.4, 35.4, 78.8 and 137.0 mg kg−1 diet, respectively. Each diet was assigned to three replicate groups of Caspian trout (initial average weight of 9.73 ± 0.34 g) for eight weeks. Weight gain ratio (WGR), specific growth rate (SGR), and protein efficiency ratio (PER) were found to be significantly enhanced by increasing dietary vitamin E level and reached to the highest values in fish fed with 78.8 mg kg−1 vitamin E supplemented diet (P < 0.05). A significantly linear increasing trend was recorded in crude protein, fat content, superoxide dismutase (SOD) activity, liver vitamin E concentration, immunoglobulin M (IgM), and alternative complement activity (ACH50), while glutathione peroxidase (GPX) activity was linearly and quadratically enhanced in response to increasing dietary vitamin E supplementations (P < 0.05). There were also linearly and quadratically decreasing trend in alkaline phosphatase (ALP), aspartate aminotransferase (AST), alanine aminotransferase (ALT) activities as well as serum glucose (GLC) and malondialdehyde (MDA) levels by supplementing dietary vitamin E (P < 0.05). Analysis by the polynomial regression of SGR, GLC, and SOD activity against varying levels of dietary vitamin E revealed that the optimum dietary vitamin E requirements in Caspian trout were 79.44, 78.73, and 82.16 mg kg−1, respectively.

Dietary vitamin C requirement based on growth performance, non-specific immune response, antioxidant capacity, and liver vitamin C concentration of fingerling Channa punctatus (Bloch)

A growth trial based on growth performance, non-specific immune response, digestive enzymes and antioxidant status, hematological parameters, body composition, and liver vitamin C concentration was carried out to estimate the dietary vitamin C requirement by feeding test diets (450 g/kg CP, crude protein, 18.71 MJ/kg GE, gross energy) containing graded levels of vitamin C (0, 10, 20, 30, 40, 50, 60 and 80 mg/kg) to fingerling Channa punctatus (5.7 ± 0.11 g) to satiety at 09:30 and 16:30 h for 12 weeks. Optimum live weight gain, LWG (820.4 %), feed conversion ratio, FCR (1.46), protein efficiency ratio, PER (1.52) and protein deposition, PD (27.22 %) were recorded in fish fed diet with 40 mg/kg vitamin C. Significant increase was recorded in hematocrit, hemoglobin and red blood cell counts of fish fed diets with vitamin C up to 40 mg/kg. Vitamin C levels in diets affected liver superoxide dismutase and catalase activities significantly and were found to be increased up to 50 mg vitamin C per kg diet. Also, the highest lysozyme, tissue serum protein, alkaline phosphatase, and intestinal enzymatic activities were noted at this level of dietary vitamin C. Liver vitamin C concentrations increased linearly (P < 0.05) with the increase in dietary vitamin C from 0 to 50 mg/kg followed by no significant increase with further increase in dietary vitamin C. Based on broken-line regression analysis of LWG, PD, glutathione peroxidase, protease activities and liver vitamin C concentration of this spotted murrel against graded levels of dietary vitamin C, the requirement ranging between 38.2–47.9 mg vitamin C per kg diet is recommended.

Influence of dietary vitamin E (DL‐alpha‐tocopheryl acetate) and diludine (diethyl 1,4‐dihydro‐2,6‐dimethyl‐3,5‐pyridinedicarboxylate) levels on growth and lipid peroxidation in rainbow trout, Oncorhynchus mykiss

We aimed to investigate the influence of dietary vitamin E and diludine on growth and lipid peroxidation (malondialdehyde; MDA) in rainbow trout. Fish (1.5 g) were fed different dietary levels of vitamin E (0, 50 and 100 mg/kg) and diludine (0, 0.5 and 1 g/kg) for 10 weeks. Growth performance and feed conversion ratio (FCR) were significantly affected by dietary vitamin E (p < .05) but not diludine. Fish fed 50 mg/kg dietary vitamin E with no diludine had significantly better growth and lower FCR than those fed vitamin E free diets. Liver vitamin E content was significantly influenced by dietary vitamin E and diludine (p < .05). The highest hepatic vitamin E was in fish fed the highest dietary vitamin E and diludine levels. Hepatic MDA level was significantly affected by dietary vitamin E and diludine (p < .05), decreasing with the increase in both dietary vitamin E and diludine. According to our results, diludine had no significant effect on growth; however, decreased hepatic lipid peroxidation independent of vitamin E. Our results reveal that 50 mg/kg vitamin E content is suitable for optimal growth and FCR in rainbow trout juveniles. However, dose dependent effects of dietary diludine remain uncertain and need further researches.

Effects of stocking density and dietary vitamin C on performance, meat quality, intestinal permeability, and stress indicators in broiler chickens.

The objective of the current study was to investigate the effects of stocking density (SD) and dietary supplementation of vitamin C on growth performance, meat quality, intestinal permeability, and stress indicators in broiler chickens. The study was conducted using a completely randomized design with a 2 × 2 factorial arrangement consisting of 2 different SD and 2 supplemental levels of dietary vitamin C. A total of 1,368 Ross 308 broiler chickens of 21 days of age with similar body weights (BW) were randomly allotted to 1 of 4 treatments with 6 replicates each. Different numbers of birds per identical floor pen (2.0 m × 2.4 m) were used to create 2 different SD levels of low SD (9 birds/m2) and high SD (18 birds/m2). The basal diet was formulated with no supplemental vitamin C to meet or exceed nutrient recommendations of the Ross 308 manual. The other diet was prepared by supplementing 200 mg/kg vitamin C in the basal diet. The study lasted for 14 days. At the end of the study, 3 male birds per replicate were selected to analyze meat quality, intestinal permeability, and stress indicators such as blood heterophil:lymphocyte (H:L) and feather corticosterone (CORT) concentrations. Results indicated that there were no interactions between different SD and dietary supplementation of vitamin C for all measurements. For the main effects of SD, birds raised at high SD had less (p < 0.01) BW, BW gain, and feed intake with increasing stress responses including greater blood H:L and feather CORT concentrations (p < 0.01) than those raised at low SD. Transepithelial electrical resistance in the jejunal mucosa was decreased (p < 0.05) at high SD, indicating an increase in intestinal permeability. However, the main effects of dietary supplementation of 200 mg/kg vitamin C were insignificant for all measurements. In conclusion, high SD of broiler chickens impairs growth performance and intestinal barrier function with increasing stress responses. However, dietary supplementation of vitamin C may have little beneficial effects on broiler chickens raised at the high SD condition used in the present study.

Retinoid Signaling in Intestinal Epithelial Cells Is Essential for Early Survival From Gastrointestinal Infection.

Vitamin A deficiency (A–) increases morbidity and mortality to gastrointestinal (GI) infection. Blocking retinoid signaling (dominant negative retinoic acid receptor, dnRAR) in intestinal epithelial cells (IEC, IECdnRAR) had no effect on vitamin A absorption, the expression of tight junction proteins or the integrity of the barrier. Immune cells in the gut were present in normal frequencies in the IECdnRAR mice, with the exception of the T cell receptor (TCR)αβ+/CD8αα cells, which were significantly lower than in wildtype littermates. Challenging the IECdnRAR mice with dextran sodium sulfate to induce colitis or Citrobacter rodentium infection resulted in similar disease to wildtype littermates. Feeding mice vitamin A deficient diets reduced vitamin A status and the A– IECdnRAR mice developed more severe colitis and C. rodentium infection. In particular, retinoid signaling in the IEC was crucial for the A– host to survive early infection following C. rodentium. Treating A– mice with retinoic acid (RA) beginning on the day of infection protects most mice from early lethality. However, RA treatment of the A– IECdnRAR mice was ineffective for preventing lethality following C. rodentium infection. Retionid signaling in IEC is critical, especially when there are reduced levels of dietary vitamin A. IEC are direct targets of vitamin A for mounting early defense against infection.