Antioxidants in Animal Feed

Production animals are often exposed to several oxidative stress conditions, including, but not limited to, heavy metals, alternative protein sources, environmental stress, disease, high densities, as well as handling, which may suppress growth performance, animal health and production, subsequently impacting economic feasibility [...] Full article

The overconsumption of carbohydrates induces oxidative stress and lipid accumulation in the liver, which can be alleviated by modulation of intestinal microbiota; however, the underlying mechanism remains unclear. Here, we demonstrated that a strain affiliated with Lactobacillus plantarum (designed as MR1) efficiently attenuated lipid deposition, oxidative stress, as well as inflammatory response, which are caused by high-carbohydrate diet (HC) in fish with poor utilization ability of carbohydrates. Serum untargeted metabolome analysis indicated that pyrimidine metabolism was the significantly changed pathway among the groups. In addition, the content of serum uridine was significantly decreased in the HC group compared with the control group, while it increased by supplementation with L. plantarum MR1. Further analysis showed that addition of L. plantarum MR1 reshaped the composition of gut microbiota and increased the content of intestinal acetate. In vitro experiment showed that sodium acetate could induce the synthesis of uridine in hepatocytes. Furthermore, we proved that uridine could directly ameliorate oxidative stress and decrease liver lipid accumulation in the hepatocytes. In conclusion, this study indicated that probiotic L. plantarum MR1 ameliorated high-carbohydrate diet-induced hepatic lipid accumulation and oxidative stress by increasing the circulating uridine, suggesting that intestinal microbiota can regulate the metabolism of nucleotides to maintain host physiological homeostasis. Full article

In aquaculture, fish are often exposed to several stress conditions, which will cause oxidative disorder and bring about health and quality problems. Arthrospira platensis contains abundant bioactive ingredients, which are beneficial for animal health. This study was conducted to investigate the effects of A. platensis on pigmentation, antioxidant capacity, and stress response after air exposure of fish. A total of 120 yellow catfish Pelteobagrus fulvidraco (initial weight 70.19 ± 0.13 g) were divided into three tanks per treatment and fed diets supplemented with 0 g kg⁻¹ A. platensis (CON) and 20 g kg ⁻¹ A. platensis (AP) for 65 days. The results indicated that dietary A. platensis had no effects on the growth of yellow catfish. The AP diet significantly reduced lactic acid (LD) and cortisol levels stimulated by air exposure stress (p < 0.05). Dietary A. platensis significantly increased plasma superoxide dismutase (SOD) and glutathione peroxidase (GPX) activities and glutathione (GSH) contents, and the relative expression levels of sod and cat, to protect against oxidative stress caused by air exposure (p < 0.05). The AP diet significantly improved the relative expression level of nrf2 (nuclear factor erythroid-2 related factor 2), while the relative expression level of keap1 (kelch-like ECH associated protein 1) was downregulated, and the protein levels of liver Nrf2 were significantly increased after air exposure stimuli (p < 0.05). Dietary A. platensis significantly increased skin lutein contents, increased skin redness, yellowness and chroma (p < 0.05), and improved body color abnormalities after oxidative stress caused by air exposure stimuli. Skin yellowness was associated with lutein contents and the expression levels of some antioxidant genes to varying degrees. Overall, dietary A. platensis could be utilized as a feed additive to activate the antioxidant response, as well as alleviate oxidative stress and pigmentation disorder induced by air exposure. Full article

Aiming to optimize soymeal-based diets for Japanese seabass (Lateolabrax japonicas), a 105-day feeding trial was conducted to evaluate the effects of functional additives, including antioxidants (ethoxyquin, thymol and carvacrol) and chelated trace elements (Cu, Mn and Zn), on the growth, immunity, antioxidant capacity and disease resistance of fish fed diets with conventional soybean meal replacing 50% of fishmeal. Three isonitrogenous (45%) and isolipidic (11%) diets were formulated: (1) standard reference diet (FM, 42% fishmeal); (2) soymeal-based diet (SBM, 21% fishmeal and 30% conventional soybean meal); (3) SBM diet supplemented 0.0665% functional additives (FAS). Each experimental diet was randomly fed to quadruplicate groups of forty feed-trained Japanese seabass (initial average body weight = 125.6 ± 0.6 g) stocked in a saltwater floating cage. Upon the conclusion of the feeding trial, lower feed intake was observed in fish fed SBM compared to those fed FM and FAS. Fish fed FM showed the highest growth performance, estimated as the weight gain rate. Notably, FAS supported faster growth of fish than those fed SBM, indicating the optimal growth performance of dietary functional additives. The feed conversion rate showed the opposite trend among dietary treatments, with the highest value in fish fed SBM. Regarding immunity, fish fed soymeal-based diets suppressed the serum alternative complement pathway activities compared to FM, whereas the respiratory burst activity in macrophages of head kidneys showed a similar picture, but no statistical differences were observed. Further, fish fed soymeal-based diets had lower serum Cu-Zn SOD, CAT and GPx activities as well as liver vitamin E levels and scavenging rates of hydroxyl radical but higher liver MDA contents compared to the FM-fed group. Fish fed FAS had higher serum Cu-Zn SOD and GPx activities and liver vitamin E levels than those fed SBM, suggesting the enhancement of antioxidant capacity of dietary functional additives. For the disease resistance against Vibrio harveyi infection, fish fed SBM had the highest cumulative mortality, followed by the FAS and FM groups. Additionally, the biomarkers related to the immune and antioxidant capacities had a positive correlation with the relative abundance of Paracoccus and Pseudomonas, while liver MDA levels had a negative correlation with the relative abundance of Pseudomonas and Psychrobacter. Collectively, soymeal replacing 50% of fishmeal suppressed the growth, immunity, antioxidant capacity and disease resistance of Japanese seabass, while dietary supplementation of antioxidants and chelated trace elements could mitigate soymeal-induced adverse effects on growth and disease resistance through the improvement in antioxidant capacity and regulation of gut microbiota. Full article

Previous studies have found that vitamin C (VC) has protective effects in fish. However, the efficacy of VC on hypoxia-induced liver injury in fish remains unknown. Therefore, to investigate the protective mechanism of VC on liver injury after acute hypoxic stimulation in fish, gibel carp were fed a diet containing VC for eight weeks, then were subjected to acute hypoxia stimulation. The specific growth rate of fish was increased by the supplementation of VC. Plasma stress markers (glucose, lactic acid, and cortisol) were decreased by the VC supplementation. Moreover, the levels of the inflammatory cytokines (tnf-α, il-2, il-6, and il-12) were increased by enhancing the Nrf2/Keap1 signaling pathway. Upregulation of the antioxidant enzymes activity (CAT, SOD, and GPx); T-AOC; and anti-inflammatory factors (il-4 and tgf-β) highlighted the antioxidant and anti-inflammatory activities of VC. The results showed that VC reduced the apoptotic index of the fish hypothalamus. The expression of GRP78 protein in the liver and endoplasmic reticulum stress and apoptosis induced by hypoxia were inhibited by VC. Taken together, the results indicate that VC can attenuate oxidative damage, inflammation, and acute hypoxia induced apoptosis in gibel carp via the Nrf2/Keap1 signaling pathway. The results identify a new defense strategy of gibel carp in response to hypoxic conditions. Full article

This study evaluated the potential effects of adding acidifiers to the drinking water on the growth performance, complete blood count, antioxidant indicators, and diversity of gastrointestinal microbiota for weaned pigs. A total of 400 weaned pigs were randomly divided into four treatments. Pigs were fed the same basal diet and given either water (no acidifier was added, control) or water plus blends of different formulas of acidifiers (acidifier A1, A2, or A3) for 35 days. On d 18 and 35 of the experimental period, 64 pigs (four pigs per pen) were randomly selected to collect blood for a CBC test (n = 128) and an antioxidant indicators test (n = 128); 24 pigs (six pigs per group) were randomly selected to collect fresh feces (n = 48) from the rectum for 16S rRNA gene sequencing. Compared to the control, supplementing the drinking water with acidifiers improved the growth performance and survival rate of weaned pigs. Acidifier groups also increased serum catalase (CAT) and total antioxidant capacity (T-AOC) activities, while also displaying a decreased malondialdehyde (MDA) concentration compared to the control. The relative abundance of Firmicutes in the acidifier A1 group was greater than that in the control group (p < 0.05) on d 35; the relative abundance of Lactobacillus in the acidifier A1 group was greater than that in the control group (p < 0.05) on d 18 and 35. The microbial species Subdoligranulum or Ruminococcaceae_UCG-005 had significantly positive correlations with ADG and ADFI or with serum antioxidant indicators, respectively. These findings suggest that supplementing the drinking water with an acidifier has a potential as an antioxidant, which was reflected in the improvement of growth performance, immunity, antioxidant capacity, and intestinal flora. Full article

Palmitic acid (PA) is a saturated fatty acid (SFA) that can cause an inflammatory response, while docosahexaenoic acid (DHA) is always used as a nutritional modulator due to its anti-inflammatory properties. However, the potential molecular mechanism is still not completely elucidated in fish. Herein, the PA treatment induced an inflammatory response in macrophages of large yellow croaker (Larimichthys crocea). Meanwhile, the mRNA expression of Toll-like receptor (TLR)-related genes, especially tlr22, and the phosphorylation of the mitogen-activated protein kinase (MAPK) pathway were significantly upregulated by PA. Further investigation found that the PA-induced inflammatory response was suppressed by tlr22 knockdown and MAPK inhibitors. Moreover, the results of the peroxisome proliferator-activated receptor γ (PPARγ) agonist and inhibitor treatment proved that PPARγ was involved in the PA-induced inflammation. PA treatment decreased the protein expression of PPARγ, while tlr22 knockdown and MAPK inhibitors recovered the decreased expression. Besides, the PA-induced activation of Nrf2 was regulated by p38 MAPK. Furthermore, DHA-executed anti-inflammatory effects by regulating the phosphorylation of the MAPK pathway and expressions of PPARγ and Nrf2. Overall, the present study revealed that DHA alleviated PA-induced inflammation in macrophages via the TLR22-MAPK-PPARγ/Nrf2 pathway. These results could advance the understanding of the molecular mechanism of the SFA-induced inflammatory response and provide nutritional mitigative strategies. Full article

An 8-week feeding trial was conducted to investigate the effects of high-starch diets and the supplementation of an olive extract (OE) on the growth performance, liver health and lipid metabolism of largemouth bass (Micropterus salmoides). Four isonitrogenous and isolipidic diets were prepared: two basal diets containing low (9.0%) and high (14.4%) levels of starch (named as LS and HS), and 0.125% OE was supplemented to each basal diet (named LSOE and HSOE). The results show that high-starch diets had significant negative effects on growth performance, with lower FR, SGR and higher FCR, whereas OE significantly lowered FCR, determined by two-way ANOVA analysis. High-starch diets induced oxidative stress, inflammatory response and liver function injury, with significant increases in the content of plasmatic AKP, AST, ALT, hepatic SOD and MDA, and up-regulation of hepatic TNFα, IL1β, and TGFβ1 gene expression. In addition, a high-starch diet decreased the phosphorylation of AMPK and upregulated the expression of SREBP, together with higher hepatic liver lipid and HSI. The oxidative stress and lipid metabolism disorders indicate metabolic liver disease (MLD) of largemouth bass fed high-starch diets. Feeding on OE-supplemented diets increased the hepatic antioxidant capacity by decreasing the content of MDA and SOD. Fish fed the HSOE diet had an activated phosphorylation of JNK and decreased expression of pro-inflammatory IL1β compared with those fed the HS diet, which strongly indicated that the degree of inflammatory responses was reduced after OE supplementation. Interestingly, this study demonstrated that OE regulates hepatic lipid metabolism in fish by inhibiting the expression of hepatic lipogenesis genes (ACC1 and FASN) and promoting lipolysis (ATGL) and β-oxidation (CPT1α) to prevent TG accumulation. In conclusion, high-starch feed induced oxidative stress and lipid metabolic disorder of largemouth bass, while supplementation with OE improved its antioxidant capacity, anti-inflammatory responses and lipid metabolism. However, hepatic histopathological results suggested that OE supplementation could not completely repair the MLD caused by the high level of starch in largemouth bass. Full article

Weaning stress affects the health and performance of calves. L-glutamine (L-Gln) is commonly used as a functional antioxidant and energy supplement in the body. However, dietary L-Gln supplementation improving weaning stress of calves is unclear. Thus, we aimed to explore the effects of L-Gln (provided by rumen-protected L-Gln) on calves during weaning. Seventy-five Holstein calves (54.0 ± 2.68 kg; 42 ± 2.1 d of age) were assigned to five groups: no supplementation and L-Gln with 1%, 2%, 3%, and 4% dry matter daily intake (DMI) supplementation groups, respectively. The experiment lasted for 28 days (42–70 d of age of calves), and the calves were weaned at 15 d of experiment. DMI and body weekly weight of all calves were recorded. Blood samples of nine healthy calves with similar body weight were collected from each group at 0, 7, 14, 16, 18, 21, and 28 d of experiment for detecting serum L-Gln, glucose, insulin, urea nitrogen, D-lactate, cortisol, haptoglobin, interleukin-8, immunoglobulin (Ig) G, IgA, IgM, total antioxidant capacity, superoxide dismutase, glutathione peroxidase, catalase, and malondialdehyde. At the end of the experiment, six healthy calves with similar body weight from each group were selected for slaughter and morphological analysis of small intestine tissue. The results showed that the L-Gln supplementation in the diets improved the negative effects of sudden weaning in calves. Furthermore, compared to the higher-level L-Gln supple-mentation (3 and 4% of DMI) groups, the dietary lower-level L-Gln supplementation (1 and 2% of DMI) had higher average daily gain, glutathione peroxidase and IgG concentration, and villus height/crypt depth of the duodenum and jejunum, as well as lower cortisol, haptoglobin, and interleukin-8 concentration of weaned calves. These results provided effective reference for relieving the negative effects of calves during weaning. Full article

The dual stress of reduced feed intake and increased milk yield in dairy cows early postpartum results in a negative energy balance. Rumen-protected glucose (RPG) has been reported to replenish energy, increase milk yield, and improve gut health. However, early postpartum cows often develop an insulin resistance, implying that RPG may not be well utilized and increased milk production may increase the liver’s fat oxidization burden. This study aimed to investigate the effects of RPG on the hepatic oxidative/antioxidative status and protein profile. Starting 7 d before expected calving, six pairs of cows were supplemented with rumen-protected glucose (RPG, n = 6) or with an equal amount of rumen-protecting coating fat (CON, n = 6). Liver samples were obtained from 10 cows 14 d after calving (d 14). Concentration of malondialdehyde and activity of glutathione peroxidase were increased and the activities of catalase and superoxide dismutase tended to increase in the livers of the RPG cows compared to the CON cows. The revised quantitative insulin sensitivity check index (RQUICKI) was decreased by RPG, but triacylglycerol concentration in liver was increased by RPG supplementation. The overall profiles of hepatic proteins were similar between CON and RPG. A partial least square regression was conducted to identify the proteins associated with liver lipidosis, oxidative stress, and antioxidative capacity. The top twenty proteins, according to their variable importance value, were selected for metabolic pathway enrichment analysis. Eighteen enriched KEGG pathways were identified, including metabolism, the citrate cycle, propanoate metabolism, the peroxisome, and type II diabetes mellitus. Our study showed that RPG supplementation reduced insulin sensitivity but increased the liver triglyceride concentration and the oxidative stress in early postpartum cows. Liver proteins related to lipidosis, oxidative stress, and antioxidative capacity, were positively associated with the glutamine metabolism, citric acid cycle, peroxisome, and type II diabetes pathways, which may indicate an increased risk of liver metabolic disorders caused by RPG supplementation in early postpartum cows. Full article

Methionine, as an essential amino acid, play roles in antioxidant defense and the regulation of immune responses. This study was designed to determine the effects and mechanisms of increased consumption of methionine by sows and piglets on the capacity of the progeny to counteract lipopolysaccharide (LPS) challenge-induced injury in the liver and spleen of piglets. Primiparous sows (n = 10/diet) and their progeny were fed a diet that was adequate in sulfur amino acids (CON) or CON + 25% total sulfur amino acids as methionine from gestation day 85 to postnatal day 35. A total of ten male piglets were selected from each treatment and divided into 2 groups (n = 5/treatment) for a 2 × 2 factorial design [diets (CON, Methionine) and challenge (saline or LPS)] at 35 d old. After 24 h challenge, the piglets were euthanized to collect the liver and spleen for the histopathology, redox status, and gene expression analysis. The histopathological results showed that LPS challenge induced liver and spleen injury, while dietary methionine supplementation alleviated these damages that were induced by the LPS challenge. Furthermore, the LPS challenge also decreased the activities of GPX, SOD, and CAT and upregulated the mRNA and(or) protein expression of TLR4, MyD88, TRAF6, NOD1, NOD2, NF-kB, TNF-α, IL-8, p53, BCL2, and COX2 in the liver and (or) spleen. The alterations of GPX and SOD activities and the former nine genes were prevented or alleviated by the methionine supplementation. In conclusion, the maternal and neonatal dietary supplementation of methionine improved the ability of piglets to resist LPS challenge-induced liver and spleen injury, potentially through the increased antioxidant capacity and inhibition of TLR4 and NOD signaling pathway. Full article

High-cost milk proteins necessitate cheaper, effective milk replacer alternatives, such as plant proteins. To examine plant protein-based milk replacer’s impact on growth performance, serum immune and antioxidant indicators, and liver transcriptome profiles in suckling calves. We assigned 28 newborn Holstein calves (41.60 ± 3.67 kg of body weight at birth) to milk (M) or milk replacer (MR) and starter diets pre-weaning (0–70 d of age) but with the same starter diet post-weaning (71–98 d of age). During the pre-weaning period, compared with the M group, MR group had significantly lower body weight, withers height, heart girth, average daily gain, feed efficiency, serum immunoglobulin (Ig) M concentration, superoxide dismutase concentration, and total antioxidant capacity; whereas they had significantly higher serum aspartate aminotransferase concentration. During the post-weaning period, MR group presented significantly higher average daily gain, alanine transaminase, aspartate aminotransferase, and malonaldehyde concentrations; whereas they had significantly lower serum IgA and IgM concentrations than the M group. Transcriptome analysis revealed 1, 120 and 293 differentially expressed genes (DEGs; MR vs. M group) in the calves from pre- and post-weaning periods, respectively. The DEGs related to xenobiotic and lipid metabolism and those related to energy metabolism, immune function, and mineral metabolism were up- and downregulated, respectively, during the pre-weaning period; during the post-weaning period, the DEGs related to osteoclast differentiation and metabolic pathways showed difference. In this study, compared with M group, MR group had the same growth performance during the overall experimental period; however, MR affected the hepatic metabolism, immune, and antioxidant function of calves. These observations can facilitate future studies on milk replacers. Full article

Acremonium terricola culture (ATC) has similar bioactive constituents to Cordyceps and is known for its nutrient and pharmacological value, indicating the potential of ATC as a new feed additive in dairy cow feeding. The primary aim of this experiment was to investigate the effects of increasing amounts of ATC in diets on milk performance, antioxidant capacity, and rumen fermentation, and the secondary aim was to evaluate the potential effects of high doses of ATC. A total of 60 multiparous Holstein cows (110 ± 21 days in milk; 2.53 ± 0.82 parity) were assigned into 15 blocks and randomly assigned to one of four groups: 0, 30, 60, or 300 g/d of ATC per cow for 97 days. Data were analyzed using repeated measures in the Mixed procedure. Dry-matter intake was not changed (p > 0.05), while energy-corrected milk and fat-corrected milk yields increased linearly and quadratically, and somatic cell count in milk decreased linearly and quadratically (p < 0.05). The lactation efficiency and the yields of milk fat and protein increased linearly (p < 0.05). On day 90, serum catalase level, total oxidative capacity, glutathione peroxidase, immunoglobulin A, and immunoglobulin M concentrations were significantly higher in the 60 and 300 g/d groups than in the 0 g/d group (p < 0.05). ATC addition showed linear effects on total volatile fatty acid (VFA), acetate, branched VFA concentrations, and rumen pH (p < 0.05). Supplementing 60 and 300 g/d ATC significantly affected the bacterial composition (p < 0.05). The relative abundance of Christensenellaceae_R–7_group and Lachnospiraceae_NK3A20_group were significantly increased by 60 g/d supplementation, and the relative abundance of Erysipelotrichaceae_UCG_002, Acetitomaculum, Olsenella, and Syntrophococcus were significantly increased by 300 g/d supplementation (p < 0.05). ATC was effective in enhancing rumen fermentation and reducing somatic cell count in milk, thereby improving milk yield. The optimized dose of ATC was 60 g/d for lactating cows, and there were no risks associated with high doses of ATC. Full article

Fish is an important animal-source food for humans. However, the oxidative stress-induced by intensive aquaculture usually causes deterioration of fish meat quality. The nutritional way has been considered to be a useful method for improving fish flesh quality. This study using the same growth experiment as our previous study was conducted to investigate whether vitamin A could improve flesh quality by enhancing antioxidative ability via Nrf2/Keap1 signaling in fish muscle. Six diets with different levels of vitamin A were fed to grass carp (Ctenopharyngodon idella) (262.02 ± 0.45 g) for 10 weeks. Dietary vitamin A significantly improved flesh sensory appeal and nutritional value, as evident by higher pH_24h value, water-holding capacity, shear force, contents of protein, lipid, four indispensable amino acids (lysine, methionine, threonine, and arginine) and total polyunsaturated fatty acid in the muscle. Furthermore, dietary vitamin A reduced oxidative damage, as evident by decreased levels of muscle reactive oxygen species, malondialdehyde, and protein carbonyl, enhanced activities of antioxidative enzyme (catalase, copper/zinc superoxide dismutase (CuZnSOD), MnSOD, glutathione peroxidase, and glutathione reductase), as well as increased content of glutathione, which was probably in relation to the activation of nuclear factor erythroid 2-related factor 2 (Nrf2) signaling. These findings demonstrated that dietary vitamin A improved flesh quality probably by enhancing antioxidant ability through Nrf2/Keap 1a signaling in fish. Full article

The susceptibility of animals to pathogenic infection is significantly affected by nutritional status. The present study took yellow catfish (Pelteobagrus fulvidraco) as a model to test the hypothesis that the protective roles of glutamine during bacterial infection are largely related to its regulation on the immune and antioxidant system, apoptosis and autophagy. Dietary glutamine supplementation significantly improved fish growth performance and feed utilization. After a challenge with Flavobacterium columnare, glutamine supplementation promoted il-8 and il-1β expression via NF-κB signaling in the head kidney and spleen, but inhibited the over-inflammation in the gut and gills. Additionally, dietary glutamine inclusion also enhanced the systematic antioxidant capacity. Histological analysis showed the protective role of glutamine in gill structures. Further study indicated that glutamine alleviated apoptosis during bacterial infection, along with the reduced protein levels of caspase-3 and the reduced expression of apoptosis-related genes. Moreover, glutamine also showed an inhibitory role in autophagy which was due to the increased activation of the mTOR signaling pathway. Thus, our study for the first time illustrated the regulatory roles of glutamine in the fish immune and antioxidant system, and reported its inhibitory effects on fish apoptosis and autophagy during bacterial infection. Full article

Melatonin (MT) is a bio-antioxidant that has been widely used to prevent pregnancy complications, such as pre-eclampsia and IUGR during gestation. This experiment evaluated the impacts of dietary MT supplementation during pregnancy on reproductive performance, maternal–placental–fetal redox status, placental inflammatory response, and mitochondrial function, and sought a possible underlying mechanism in the placenta. Sixteen fifth parity sows were divided into two groups and fed each day of the gestation period either a control diet or a diet that was the same but for 36 mg of MT. The results showed that dietary supplementation with MT increased placental weight, while the percentage of piglets born with weight < 900 g decreased. Meanwhile, serum and placental MT levels, maternal–placental–fetal redox status, and placental inflammatory response were increased by MT. In addition, dietary MT markedly increased the mRNA levels of nutrient transporters and antioxidant-related genes involved in the Nrf2/ARE pathway in the placenta. Furthermore, dietary MT significantly increased ATP and NAD⁺ levels, relative mtDNA content, and the protein expression of Sirt1 in the placenta. These results suggested that MT supplementation during gestation could improve maternal–placental–fetal redox status and reproductive performance by ameliorating placental antioxidant status, inflammatory response, and mitochondrial dysfunction. Full article

Dietary lipids provide energy for growth and development and provide fatty acids necessary for normal structure and biological function. However, oxidized lipids cause oxidative stress and intestinal damage. An 8-week feeding trial with fresh fish oil (FFO, control group), oxidized fish oil (OFO), and taurine-supplemented diets (OFOT, OFO + 0.2% of taurine) was conducted to evaluate the protective effect of taurine on oxidized fish-oil-induced liver oxidative stress and intestine impairment in juvenile Ictaluruspunctatus. The results showed that (1) Growth performance was significantly lower in fish fed OFO than in those fed other diets, whereas the opposite occurred in the hepatosomatic index. (2) OFO-feeding significantly increased lipid deposition compared with the FFO group. The addition of taurine ameliorated the OFO-induced increase in lipid vacuolization in the liver, significantly upregulated lpl mRNA expression, and downregulated fas and srebp1 mRNA expression. (3) OFO-feeding significantly reduced oxidative damage of liver. Compared with the OFO group, the OFOT group remarkably upregulated antioxidant enzyme mRNA expression through the Nrf2-Keap1 signaling pathway based on the transcriptional expression. (4) OFO diets induced intestinal physical and immune barrier damage. Compared with the OFO group, OFOT diets remarkably downregulated il-1β, il-6, tnf-α, and il-8 mRNA expression and upregulated tgf-β mRNA expression through the NF-κB signaling pathway. Besides, the addition of taurine to OFO diets significantly upregulated zo-2 and zo-1 mRNA expression, and downregulated claudin-15 and claudin-12 mRNA expression. In conclusion, oxidized-fish-oil diets can cause negative physiological health effects in Ictaluruspunctatus, while adding taurine can increase growth and antioxidant ability, reduce lipid deposition, and improve intestinal health. Full article

The poultry ovary is used as a classic model to study ovarian biology and ovarian cancer. Stress factors induced oxidative stress to cause follicle atresia, which may be a fundamental reason for the reduction in fertility in older laying hens or in aging women. In the present study, we set out to characterize the relationships between oxidative stress and ovarian function. Layers (62 weeks of age; BW = 1.42 ± 0.12 kg) were injected with tert-butyl hydroperoxide (tBHP) at 0 (CON) and 800 μmol/kg BW (oxidative stress group, OS) for 24 days and the role of melatonin (Mel) on tBHP-induced ovary oxidative stress was assessed through ovary culture in vitro. The OS (800 μmol/kg BW tert-butyl hydroperoxide) treatment decreased the reproduction performance and ovarian follicle numbers. OS decreased the expression of SIRT1 and increased the P53 and FoxO1 expression of the ovary. A decreased Firmicutes to Bacteroidetes ratio, enriched Marinifilaceae (family), Odoribacter (genus) and Bacteroides_plebeius (species) were observed in the cecum of the OS group. Using Mel in vitro enhanced the follicle numbers and decreased the ovary cell apoptosis induced by tBHP. In addition, it increased the expression of SIRT1 and decreased the P53 and FoxO1 expression. These findings indicated that oxidative stress could decrease the laying performance, ovarian function and influence gut microbiota and body metabolites in the layer model, while the melatonin exerts an amelioration the ovary oxidative stress through SIRT1-P53/FoxO1 pathway. Full article