Addition of açai oil during the close-up dry period of Holstein cows improves colostrum quality and immune responses of their calves.

This study evaluated of the effects of açai oil during the close-up dry period of Holstein cows on colostrum quality, as well as on the immune and antioxidant responses of their calves. Sixteen multiparous cows were assigned randomly to two treatments: 1) CONTROL (n = 8) - 4.48% of soybean oil/concentrate; 2) AÇAI (n =8) - 4.48% of açai oil/concentrate. Cows fed with açai oil had greater (P≤0.04) colostrum concentrations of immunoglobulins (Ig) G (1st and 2nd milking), IgG heavy chains, IgA (only at 1st milking), alpha-lactalbumin (1st milking), total protein, and antioxidant capacity against peroxyl radicals (only at 1st milking). Cows fed with açai oil had greater serum concentrations of globulin (only on the day of calving) and total protein (only on the day of calving) (P = 0.03). Calves born of cows fed with açai oil had greater serum concentrations of total protein (only 24 and 48 h after calving) and serum concentration of IgG heavy chain (only 24 h after calving) and globulin (only 24 and 48 h after calving) (P = 0.01). These data suggest that the addition of açai oil in the cow feed during the close-up dry period boosted immunity in their calves by altering the composition of colostrum.

Microencapsulated phytogenic in dog feed modulates immune responses, oxidative status and reduces bacterial (Salmonella and Escherichia coli) counts in feces.

Improving the health and immunity of pets is a concern of the guardians, while maintaining the health of the animals directly impacts the owners' health and public health. The objective of this study was to produce a dog feed containing a microencapsulated phytogenic blend, as well as determine the impact of the additive on animal health and its intestinal microbiota. The composition included microencapsulated thymol, carvacrol, and cinnamaldehyde, at 300 mg/kg of feed. Ten male beagle dogs were divided into two groups, identified as follows: the control group (C; ingested the feed without the additive) and the treated group (T; consumed feed containing the phytogenic blend). The dogs received 300 g of feed/day divided into two meals. Greater neutrophil counts in group T and lymphocyte counts were observed at the end of the experiment, as well as levels of α2-globulins and γ-globulin, while ß1 and ß2-globulins levels were lower in group T. Serum nitrogen oxide levels were higher in group T. Levels of reactive oxygen species were lower in group T at days 30 and 45, unlike activity of glutathione peroxidase that was higher. We found less bacterial contamination in the feces of dogs in group T, i.e., total bacterial count, total coliform counts, and counts of Salmonella and Escherichia coli were lower on days 30 and 45. Phytogenic blend intake reduces bacterial counts in stool and improves antioxidant/oxidative status and immune responses.

The addition of green propolis to laying hens had positive effects on egg quality: lower bacteria counts in the shell and lipid peroxidation in the yolk.

This study aimed to determine whether the addition of green propolis extract to the diet of laying hens would improve egg quality and bird performance and decrease bacterial contamination of eggs. Forty-five brown Hy-line laying hens were used, divided into five groups with three replicates each and three animals per cage: T0 - diet without propolis; T5 - 5 grams of propolis per kg of feed; T10 - 10 grams of propolis per kg of feed; T20 - 20 grams of propolis per kg of feed and T30 - 30 grams of propolis per kg of feed. The quality of fresh eggs was made on day 21 of the experiment, and eggs were stored for 21 days. Greater specific gravity was observed in fresh eggs in T5 birds and stored eggs for T10. TBARS in fresh eggs, we found that T30 eggs had lower levels compared to other treatments. T20 eggs had the lowest total bacterial count and the lowest total coliform count in the eggshells of T10 and T20 chickens. The count of E. coli in the peel was lower for T20 and T30 than T0 and T5. The consumption of propolis did not interfere with the hens' egg production rate but reduced food intake and consequently reduced feed conversion. We concluded that the addition of green propolis in the diet of laying birds proved efficient in reducing bacterial contamination in the eggshells and reducing the lipid peroxidation of fresh and stored eggs.

Dietary supplementation with nerolidol improves the antioxidant capacity and muscle fatty acid profile of Brycon amazonicus exposed to acute heat stress.

An increase in water temperature in the Amazon River has elicited concerns about commercially important fish species associated with food security, such as matrinxã (Brycon amazonicus). Studies have demonstrated the positive effects of diets supplemented with plant-based products that combat heat stress-induced oxidative damage. The aim of this study was to determine whether dietary supplementation with nerolidol prevents or reduces muscle oxidative damage and impairment of the fillet fatty acid profile of matrinxã exposed to heat stress. Plasma and muscle reactive oxygen species (ROS) and lipid peroxidation (LPO) levels were significantly higher in fish exposed to heat stress compared to fish not exposed to heat stress, while plasma superoxide dismutase (SOD) and glutathione peroxidase (GPx) activity was significantly lower. The total content of saturated fatty acids (SFA) in fillets was significantly higher in fish exposed to heat stress compared to fish not exposed to heat stress, while he total content of polyunsaturated fatty acids (PUFA) was significantly lower. Nerolidol prevented the increase of muscle LPO and plasma ROS and LPO levels in fish exposed to heat stress, and partially prevented the increase in muscle ROS levels. Diets containing nerolidol prevented the inhibition of muscle GPx activity in fish exposed to heat stress, and partially prevented the decrease of plasma GPx activity. The nerolidol-supplemented diet prevented the increase of fillet SFA in fish exposed to heat stress, while partially preventing the decrease of PUFA. We conclude that acute heat stress at 34 °C for 72 h causes plasma and muscular oxidative damage, and that homeoviscous adaptation to maintain membrane fluidity can represent a negative impact for fish consumers. A nerolidol diet can be considered a strategy to prevent heat stress-induced oxidative damage and impairment of muscle fatty acid profiles.

Benefits of nanotechnology: Dietary supplementation with nerolidol-loaded nanospheres increases survival rates, reduces bacterial loads and prevents oxidative damage in brains of Nile tilapia experimentally infected by Streptococcus agalactiae.

Rampant and uncontrolled use of antibiotics is a major concern for aquaculture; the practice foments the emergence of resistant strains of Streptococcus agalactiae, among other negative impacts. Constituents of plant essential oils such as nerolidol are being considered as replacements for synthetic drugs to support fish nutrition and health. There is evidence to suggest that nanotechnology may enhance the efficacy of natural bioactive compounds; this is a substantial advance for the development and sustainability of aquaculture. Against the backdrop of this evidence, we aimed determine whether dietary supplementation with free nerolidol and nerolidol-loaded nanospheres would exert bactericidal effects against S. agalactiae, as well as prevent S. agalactiae-induced brain oxidative damage. In Experiment I, we measured the antimicrobial properties of dietary supplementation of nerolidol and nerolidol nanosphere in terms of mortality, longevity and relative percent survival. Fish infected with S. agalactiae fed 0.5 and 1.0 mL nerolidol nanospheres kg/diet demonstrated lower mortality and higher relative percent survival than the control group, while longevity was higher in all infected plus supplementation groups. Experiment II showed significantly lower microbial loads in brains of fish infected with S. agalactiae that were fed 1.0 mL nerolidol nanospheres kg/diet than in the control group. Brain nerolidol levels were significantly higher in uninfected as well as infected fish supplemented with nerolidol nanospheres than in fish supplemented with free nerolidol. Finally, brain reactive oxygen species and lipid peroxidation levels were higher in infected fish supplemented with basal diet compared to uninfected fish and supplemented with basal diet, and the supplementation with 1.0 mL/kg nerolidol nanospheres prevented this augmentation caused by infection. These data suggest that dietary supplementation with nerolidol nanospheres (1.0 mL/kg diet) has potent bactericidal effects in terms of augmentation of fish longevity and survival, and reduction of brain microbial loads. Also, S. agalactiae-induced brain oxidative damage that contributed to disease pathogenesis, and the dietary supplementation with nerolidol nanospheres (1.0 mL/kg diet) prevented this alteration. In summary, nanotechnology is a compelling approach to enhancing the efficacy of nerolidol, giving rise to reduction of S. agalactiae loads in fish brains.

Effects of thymol supplementation on performance, mortality and branchial energetic metabolism in grass carp experimentally infected by Aeromonas hydrophila.

We determined whether thymol supplementation of would minimize the negative effects of Aeromonas hydrophila infection on branchial energy metabolism, weight loss and mortality in grass carp (Ctenopharyngodon idella). We found that the infected fish all died, while 62.5% of those supplemented with 100 mg/kg thymol survived. Cytosolic and mitochondrial creatine kinase (CK) activities, as well as adenylate kinase (AK) and pyruvate kinase (PK) activities were significant lower in gills of A. hydrophila-infected fish than those of the control group, and adenosine triphosphate (ATP) levels were significant lower in the infected group. Finally, branchial reactive oxygen species (ROS) were significant higher in A. hydrophila-infected fish than in the control group. Supplementation with 100 and 300 mg thymol/kg diet prevented inhibition of branchial cytosolic and mitochondrial CK activities caused by infection, and also inhibited the reduction of branchial ATP levels. Supplementation with 100, 200 and 300 mg thymol/kg prevented the inhibition of branchial AK and PK activities induced by aeromonosis. Supplementation of 100 mg thymol/kg prevented weight loss after A. hydrophila infection. These data suggest that supplementation with 100 mg thymol/kg exerts potent bactericidal properties and augments longevity. Supplementation at all concentrations of thymol prevented A. hydrophila-induced branchial bioenergetics; nevertheless, higher concentrations were associated with side-effects.

Purinergic signaling and gene expression of purinoceptors in the head kidney of the silver catfish Rhamdia quelen experimentally infected by Flavobacterium columnare.

The head kidney is a lymphoid immune organ that plays a key role in the immune and inflammatory responses of teleost fish. It is associated with immunoglobulin G production and differentiation of B cells. The presence of a multi-enzymatic complex found anchored in the plasma membrane makes the head kidney an important purinergic-dependent tissue. Purinergic signaling has been associated with these responses under pathological conditions via regulation of extracellular adenosine triphosphate (ATP), the main damage molecular associated pattern agent released during bacterial infections. The aim of this study was to determine whether purinergic signaling is a pathway associated with impairment of immune responses in silver catfish (Rhamdia quelen) experimentally infected by Flavobacterium columnare, as well as to evaluate the role of P2 purine receptors in this response. Triphosphate diphosphohydrolase (NTPDase) activity in the head kidney was significantly lower in silver catfish experimentally-infected F. columnare 72 h post-infection (hpi) than in the control group, while no significant difference was observed with respect NTPDase activity on adenosine diphosphate, as well as on 5'-nucleotidase and adenosine deaminase activities. Extracellular ATP levels were significantly higher in the head kidney of experimentally-infected fish than in the control group at 72 hpi. Finally, p2ry11 and p2rx3 purine receptor levels were significantly higher in experimentally-infected fish than in the control group at 72 hpi. We conclude that purinergic signaling in the head kidney of silver catfish infected by F. columnare creates a pro-inflammatory profile that may contribute to impairment of immune and inflammatory responses via reduction of ATP hydrolysis and its accumulation in the extracellular milieu, accompanied by upregulation of p2ry11 and p2rx3 purine receptors, leading to pro-inflammatory status.

Combination of herbal components (curcumin, carvacrol, thymol, cinnamaldehyde) in broiler chicken feed: Impacts on response parameters, performance, fatty acid profiles, meat quality and control of coccidia and bacteria.

The objective of this study was to determine whether curcumin and a commercial microencapsulated phytogenic supplement containing thymol, cinnamaldehyde and carvacrol in broiler chicken feed would improve health and meat quality (fatty acid profile), as well as to determine the coccidiostatic and bactericidal potential of the additives. The broiler chickens were divided into five groups: NC - negative control feed; PC - positive control; CU - with 50 mg/kg of curcumin, PHY - 100 mg/kg phytogenic; and PHY + CU, a combination of both additives at 50 mg/kg (curcumin) and 100 mg/kg (phytogenic). We observed significantly higher levels of total proteins associated with increased circulating globulins, as well as lower levels of uric acid, cholesterol and triglycerides in the PHY + CU group than in the NC. There were significantly fewer oocysts in birds supplemented with additives in the NC group on day 21; on day 35, the NC, PHY and PHY + CU groups had significantly lower counts than the PC and CU groups; however, at 44 days, the lowest counts were in PC group. The bacterial counts were significantly lower on day 21 in all groups that received additives than those of the control group; however, at 44 days, the bacterial and Escherichia coli counts in these groups were significantly higher than those of the control. Curcumin with or without phytogenic agent improved meat quality, with increased antioxidant levels and reduction of lipid peroxidation. There were significantly lower total saturated fatty acid levels and significantly greater monounsaturated/polyunsaturated fatty acid levels in broilers that consumed additives individually and in combination. The combination of additives significantly increased the crypt/villus ratio, a marker of improved intestinal health and performance. Additives potentiated their individual effects, suggesting they can replace conventional growth promoters without compromising health, intestinal mucosa or meat quality.

Pathogenetic effects of feed intake containing of fumonisin (Fusarium verticillioides) in early broiler chicks and consequences on weight gain.

Fusarium verticillioides is often responsible for contamination of poultry feed with the mycotoxin fumonisin. The objective of the study was to determine whether fumonisin-contaminated feed in the early phase of broiler chicks causes oxidative imbalances and interferes with weight gain. One-day-old male Cobb 500 broiler chicks (n = 80) were divided into four treatments of 20 birds each, all of which were fed basal feed until the 11th day of age. From day 12, some birds were challenged with fumonisin in the feed: Control (T0) continued receiving the basal ration; treatments T1, T2, and T3 were given feed experimentally contaminated with fumonisin at concentrations of 2.5 ppm, 5 ppm and 10 ppm, respectively. After the 5th (day 17) and 10th (day 21) days, ten birds from each treatment were euthanized for blood and tissue collection to measure histopathological, biochemical and oxidative stress markers. All animals were weighed individually at the beginning of the experiment (day 12), and at 17 and 21 days of age. Birds that ingested 10 ppm of fumonisin (T3) had lower (P < 0.05) weight gain compared to those in T0. At 21 days, the body weights of the T1, T2 and T3 chicks were 1.3%, 8.97% and 18.7% lower, respectively, than those of T0. No histological lesions in the livers were observed for any treatment; however, higher levels of reactive oxygen species (ROS: day 21) and lipoperoxidation (LPO: days 17 and 21) were observed, associated with lower liver activity of the enzymes superoxide dismutase (SOD: day 21), glutathione peroxidase (GPx: day 17 and 21) and glutathione S-transferase (GST: day 21) when birds consumed 5 or 10 ppm of fumonisin. In serum, LPO levels and SOD and GPx activities were lower for groups consuming high doses of fumonisin in the diet (T2 and T3); ROS levels and GST activity were higher in these birds. Birds that consumed fumonisin-containing diets had lower levels of alanine aminotransferase, total protein and albumin (T3); as well as lower serum glucose levels (days 17 and 21), uric acid and triglycerides (day 21) in T3 than in T0. At 21 days, there were smaller crypt sizes and intestinal villi in birds that consumed high levels of fumonisin. These results suggest that fumonisin (10 ppm) in chick diet causes hepatic oxidative stress and impairs intestinal health, consequently negatively affecting weight gain.

Branchial bioenergetics dysfunction as a relevant pathophysiological mechanism in freshwater silver catfish (Rhamdia quelen) experimentally infected with Flavobacterium columnare.

Flavobacterium columnare, the causative agent of columnaris disease, is a serious bacterial disease responsible for causing devastating mortality rates in several species of freshwater fish, leading to severe economic losses in the aquaculture industry. Notwithstanding the enormous impacts this disease can have, very little is known regarding the interaction between the host and bacterium in terms of the mortality rate of silver catfish (Rhamdia quelen), as well its linkage to gill energetic homeostasis. Therefore, we conducted independent experiments to evaluate the mortality rates caused by F. columnare in silver catfish, as well as whether columnaris disease impairs the enzymes of the phosphoryl transfer network in gills of silver catfish and the pathways involved in this inhibition. Experiment I revealed that clinical signs started to appear 72 h post-infection (hpi), manifesting as lethargy, skin necrosis, fin erosion and gill discoloration. Silver catfish began to die at 96 hpi, and 100% mortality was observed at 120 hpi. Experiment II revealed that creatine kinase (CK, cytosolic and mitochondrial) and pyruvate kinase (PK) activities were inhibited in silver catfish experimentally infected with F. columnare, while no significant difference was observed between experimental and control groups with respect to adenylate kinase activity. Activity of the branchial sodium-potassium pump (Na+, K+-ATPase) was inhibited while reactive oxygen species (ROS) and lipid peroxidation levels were higher in silver catfish experimentally infected with F. columnare than in the control group at 72 hpi. Based on these data, the impairment of CK activity elicited by F. columnare caused a disruption in branchial energetic balance, possibly reducing ATP availability in the gills and provoking impairment of Na+, K +ATPase activity. The inhibition of CK and PK activities appears to be mediated by ROS overproduction and lipid peroxidation, both of which contribute to disease pathogenesis associated with branchial tissue.

Changes in cardiac and hepatic energetic metabolism in gerbils infected by Listeria monocytogenes.

Energy metabolism is a sensitive indicator of cellular disorders. Therefore, the objective of this study was to investigate changes in cardiac and hepatic energy metabolism during listeriosis using an experimental model. We divided gerbils into two groups: Control (n = 11) and orally Infected (n = 12) with 5 × 109 CFU/mL of Listeria monocytogenes. Euthanasia and sampling were performed on days 6 and 12 post-infection (PI). Histopathological lesions were not found in the heart; however, the liver showed pyogranuloma. In the hearts of infected animals, cytosolic creatine kinase activity was lower on day 6 and 12 PI; mitochondrial creatine kinase/pyruvate kinase (PK), and sodium potassium pump (Na+/K+-ATPase) activities were lower on day 12 PI. Hepatic PK and Na+/K+-ATPase activities were lower in the infected group on day 12 PI. Lipoperoxidation was higher in the livers and hearts of infected animals on day 12 PI, and antioxidant capacity against peroxyl radicals (ACAP) was also higher in this group. These data suggest that subclinical listeriosis alters hepatic and cardiac energy metabolism, possibly related to decreased activity of phosphotransferases and ATPase. Subsequent antioxidant responses are not sufficient to correct alterations in lipid peroxidation and bioenergetics, possibly leading to important cellular pathological mechanisms.

Experimental infection by Neospora caninum in gerbil reduces activity of enzymes involved in energy metabolism.

Neospora caninum is a protozoan that has tropism for the central nervous system. The aim of this study was to determine whether experimental infection of gerbils would interfere with activity of enzymes associated with energy metabolism. We randomized 20 gerbils into two groups (ten animals per group): the control group (healthy animals; uninfected) and the infected group (experimentally infected with dose 7.8 × 102 tachyzoites of N. caninum per gerbil). On day six and twelve post-infection (PI), brain and spleen tissues were collected for biochemical and histopathological analyses. No histopathological lesions were observed in the brains of infected animals; however, inflammatory infiltrates were found in the spleen. Significantly greater levels of reactive oxygen species (ROS) were observed in the brain and spleen of infected gerbils than in the control group at 12 days PI. Cytosolic creatine kinase (CK-CYT), mitochondrial creatine kinase (CK-MIT), and pyruvate kinase (PK) activities were lower in the brains of infected gerbils than in those of the control group on day 12 PI. There was significantly less CK-CYT activity in the spleens of infected gerbils on day 6 and 12 PI. Finally, there was significantly less sodium-potassium ion pump (Na+/K+ ATPase) activity in the brains and spleens of infected gerbils on day 12 PI. These data suggest that experimental infection with N. caninum interfered with energy metabolism associated with ATP homeostasis in the brain and spleen, directly or indirectly, apparently mediated by ROS overproduction, contributing to inhibition of Na+/K+ ATPase activity.

Protective effects of diet containing rutin against trichlorfon-induced muscle bioenergetics disruption and impairment on fatty acid profile of silver catfish Rhamdia quelen.

Trichlorfon is an organophosphate insecticide that is widely used on fish farms to control parasitic infections. It has been detected in freshwater ecosystems as well as in fishery products. There is a growing body of evidence to suggest that certain feed additives may reduce or prevent pesticide-induced toxicity in fish. The aim of the present study was to determine whether acute exposure to trichlorfon would alter bioenergetic homeostasis and alter fatty acid profiles in muscles of silver catfish (Rhamdia quelen). We also sought to determine whether rutin prevents or reduces these effects. Cytosolic and mitochondrial creatine kinase (CK) and activities of complexes II-III and IV in muscle were significantly inhibited by exposure to 11 mg/L trichlorfon for 48 h compared to effects in the unexposed group. Total content of polyunsaturated fatty acids (omega-3 and omega-6) were significantly lower in muscle of silver catfish exposed to 11 mg/L trichlorfon for 48 h than in the unexposed group. Addition of 3 mg rutin/kg feed increased CK activity and prevented inhibition of complex IV activity, as well as preventing all alterations of muscle fatty acid profiles elicited by exposure to trichlorfon. No significant differences were observed between groups with respect to muscle adenylate kinase or pyruvate kinase activities, as well as total content of saturated and monounsaturated fatty acids. Our findings suggest that exposure (48 h) to 11 mg trichlorfon/L water inhibits cytosolic and mitochondrial CK activity in muscle. Trichlorfon also affects activities of complexes II-III and IV in respiratory chain, with important consequences for adenosine triphosphate production. The pesticide alters fatty acid profiles in the fish and endangers human consumers of the product. The most important finding of the present study is that inclusion of rutin improves bioenergetic homeostasis and muscle fatty acid profiles, suggesting that it reduces trichlorfon-induced muscle damage.

Effects of the inclusion of açai oil in diet of prepartum Holstein cows on milk production, somatic cell counts and future lactation.

We measured the effects of açai oil in the diets of prepartum cows to evaluate health, milk production and quality. Sixteen Holstein cows were divided into two groups: SOY used as control, and AÇAI, test group. Occurred inclusion of 4% soybean or açai oils was provided in the concentrate starting at 20 days prepartum [d -20 to d 0 (partum-day)]. The AÇAI diet increased (P=0.01) milk production (d 10 and 20) and reduced somatic cell count (d 20). In milk, no effects were detected (P≥0.10) for concentration of fat, lactose or protein as well as in terms of serum concentration of calcium, albumin or triglycerides. AÇAI diet tended to increase (P=0.09) serum concentrations of total protein, glutathione transferase (d 4), and total antioxidant capacity (d 4 and 10) and increased (P≤0.05) globulin, gamma-glutamyl transferase, superoxide dismutase and glutathione peroxidase (d 4). Further, AÇAI diet reduced the serum concentration of creatine kinase (P≤0.05) (d 0, 4 and 10), reactive oxygen species (d 0 and 4) and lipoperoxidation (d 0) and tended to reduce aspartate transaminase activity (P=0.07; d 0 and 4). Açai oil in the diets in prepartum cows improved their health as well as milk production and quality.

Curcumin addition in diet of laying hens under cold stress has antioxidant and antimicrobial effects and improves bird health and egg quality.

Curcumin is an herbal component with several biological properties, and we highlight here the thermal stability, antioxidant and anti-inflammatory activity. We determined whether curcumin supplementation in the diets of laying hens under cold stress and naturally infected with Escherichia coli would control infection, and would have positive effects on overall health, as well as egg production and quality. We allocated 36 chickens that had been naturally infected with E. coli into two groups, with six replicates and three chickens per repetition: control group and curcumin group (200 mg curcumin/kg). The experimental period lasted 42 days, and fecal, blood and egg samples were collected at 1, 21 and 42 days We found that feces and eggs had lower total bacterial counts, E. coli counts and total coliform counts in the curcumin group at 21 and 42 days. In fresh eggs, the brightness and yellow intensity (b+) were significantly higher in the curcumin group. In stored eggs, higher specific gravity, albumen height and lower yolk pH were observed in the curcumin group. Fresh eggs collected and stored on day 42 showed lower levels of lipid peroxidation in the curcumin group, while the total antioxidant capacity in the stored eggs was significantly higher in the curcumin group. The curcumin group showed lower total leukocyte counts as a result of lower numbers of neutrophils and lymphocytes, as well as lower levels of total protein, alkaline phosphatase and alanine aminotransferase. Lower serum lipoperoxidation at 42 days was observed in the curcumin group, probably because of the higher activity of glutathione peroxidase and glutathione transferase in other words, because of antioxidant stimulation. Taken together, our findings suggest that curcumin supplementation in laying hens under cold stress and with colibacillosis has positive effects on infection control because of antioxidant stimulation.

Dog food production using curcumin as antioxidant: effects of intake on animal growth, health and feed conservation.

The objectives of this study were to produce dog food containing curcumin replacing synthetic antioxidants, to evaluate its beneficial effects on animal growth and health. Curcumin (100 mg/kg) was added after the extrusion process along with the other micronutrients. The final concentration of curcumin was 32.9 mg/kg. The control feed was composed of the same ingredients without curcumin. After a storage of 6 months, feed composition and pH did not differ; however, the feed with curcumin showed lower protein oxidation, lipid peroxidation and higher total antioxidant capacity. After 2 months of feed production, 12 young Beagle dogs received either curcumin-containing food (n = 6)  or the control diet (n = 6). The animals were fed twice a day using individual kennels. Blood samples were taken on d 1, 35 and 42. During the first 30 d of the study, the animals had natural infectious diseases that were controlled with anti-protozoals and antibiotics. Greater numbers of red blood cells were observed in dogs fed with curcumin (d 35 and 45), and there were greater numbers of white blood cells as a consequence of increased neutrophils on d 42. At the end of the experiment, a significant reduction in the number of lymphocytes was observed in dogs that ingested curcumin (d 42), suggesting an anti-inflammatory effect, manifested as a decrease in globulin levels. In the final 15 d of the experiment, the animals were clinical healthy. Higher serum levels of glucose, urea, triglycerides and cholesterol were observed in dogs fed with curcumin. Curcumin increased the activity of several antioxidant enzymes in addition to non-protein thiols and the total antioxidant capacity in the serum, consequently reducing levels of oxygen reactive species. Curcumin supplementation of dogs did not favour growth or weight gain. Neverthless, it was concluded that curcumin improved animal health, with emphasis on the stimulation of the antioxidant system and evidence of an anti-inflammatory effect.

Disturbance of oxidant/antioxidant status and impairment on fillet fatty acid profiles in Brycon amazonicus subjected to acute heat stress.

Amazon fish are vulnerable to climate change. Current temperature increases in Amazonian rivers are likely to continue in the coming years. Elevated temperatures impair homeostasis and subject fish to oxidative stress; nevertheless, the effects of elevated temperature on plasma and muscle oxidative stress as well as fillet fatty acid composition in matrinxã (Brycon amazonicus) remain unknown. Therefore, the aims of the present study were to determine whether antioxidant system is able to withstand acute thermal stress to avoid plasma and muscle oxidative damage and to determine the manner in which matrinxã adjust their muscle fatty acid metabolism in a response to acute heat stress. We exposed juvenile matrinxã to four temperatures (28 °C as control and 30, 32, and 34 °C) for 72 h and observed the effects on plasma and muscle oxidant/antioxidant status and on fatty acid composition. Plasma reactive oxygen species (ROS) and lipid peroxidation (LPO) levels were significantly higher in matrinxã exposed to 34 °C compared with the control group, while they were significantly higher in the muscle of matrinxã exposed to 32 °C and 34 °C compared with the control group. Superoxide dismutase (SOD) activity and total antioxidant capacity (TAC) levels were significantly lower in the plasma and muscle of matrinxã exposed to 34 °C compared with the control group. Plasma glutathione peroxidase (GPx) activity was significantly lower in matrinxã exposed to 32 and 34 °C compared with the control group, while it was significantly lower in the muscle of matrinxã exposed to 34 °C. The total content of saturated fatty acid (SFA) was significantly higher in the fillet of matrinxã exposed to 34 °C compared with the control group, while the total content of polyunsaturated fatty acid (PUFA) was significantly lower. Based on this evidence, we conclude that acute heat stress at 32 °C and 34 °C causes plasma and muscular oxidative stress, and the enzymatic and non-enzymatic antioxidant system is unable to prevent oxidative damage. Moreover, increased levels of total SFA and decreased levels of PUFA occur in an attempt to withstand heat stress and maintain membrane fluidity; nevertheless, these responses can represent negative impacts for consumers.

Dietary exposure to ochratoxin A reduces growth performance and impairs hepatic purinergic signaling in tambaqui (Colossoma macropomum).

The practice of replacing costly animal-derived proteins with more economical plant proteins has augmented the risk of mycotoxin contamination in fish feeds, including contamination with ochratoxin A (OTA). OTA is a secondary metabolite produced by molds commonly found in fish feeds that causes impairment of performance in several fish species and some hepatic biochemical alterations. However, the pathways involved in hepatic damage remain unknown and are limited to histopathological alterations. Purinergic signaling is a homeostatic system that continuously monitors the internal environment to detect injury primarily by two intercellular messengers: adenosine triphosphate (ATP) and adenosine (Ado). The objective of this study was to determine whether OTA-contaminated feed induces the release of nucleotides in the extracellular milieu, as well as whether ectoenzymes modulate ATP pro-inflammatory effects in liver of tambaqui (Colossoma macropomum). Final mean weight, weight gain (WG), and liver weight were significantly lower in tambaqui fed feeds containing 1.6 and 2.4 mg OTA/kg feed than in the control group. Liver ATP and Ado levels were significantly higher in tambaqui fed feeds containing 1.6 and 2.4 mg OTA/kg feed compared with control, while no significant difference was observed regarding adenosine diphosphate and adenosine monophosphate levels. Hepatic triphosphate diphosphohydrolase (NTPDase) activity (for ATP) was significantly greater in tambaqui fed feeds containing 1.6 and 2.4 mg OTA/kg feed compared with control, while adenosine deaminase (ADA) activity was lower. No significant difference was observed with respect to hepatic NTPDase activity (for ADP) or for 5'-nucleotidase activity. Finally, levels of liver metabolites of nitric oxide were significantly higher in tambaqui fed feeds containing 1.6 and 2.4 mg OTA/kg feed than in the control group. Based on these data, exposure to 1.6 and 2.4 mg OTA/kg feed impaired tambaqui growth performance associated with final mean weight and WG. Levels of two important intercellular messengers, ATP and Ado, increased in the extracellular space as a consequence of hepatic damage, exerting opposite immune responses. Finally, liver NTPDase and ADA activities were altered to modulate ATP and Ado levels, respectively, exerting anti-inflammatory effects to counteract OTA-induced hepatic injury.

Benefits of thymol supplementation on performance, the hepatic antioxidant system, and energetic metabolism in grass carp.

Thymol is an herbal food additive used to improve animal performance. Thymol acts via its potential to enhance productive and reproductive performance, and by improving bioavailability of nutrients in fish. Nevertheless, the exact mechanisms associated with these phenomena remain poorly understood, although recent evidence has suggested the involvement of the phosphotransfer network and antioxidant status. Therefore, the aim of this study was to determine whether the improvement of the antioxidant/oxidant status and the phosphoryl transfer network may be involved in enhanced growth performance in grass carp (Ctenopharyngodon idella) fed with various levels of thymol (100, 200, and 300 mg/kg feed). Thymol-supplementation (100 mg/kg feed) produced higher body weight and weight gain for 60-day post-feeding compared to the control group. Specific growth rate was higher; while feed conversion ratio was lower in fish that consumed 100 mg of thymol/kg compared to other groups. Hepatic lactate dehydrogenase activity and lipid peroxidation levels were lower in the thymol-supplemented group (100 mg/kg feed) than in the control group, while reactive oxygen species were lower in all supplemented groups than in the control group. Hepatic superoxide dismutase (300 mg/kg feed) and glutathione peroxidase (100, 200, and 300 mg/kg feed) activities, as well as antioxidant capacity against peroxyl radicals (100 mg/kg feed) were higher in these groups than in the control group. Based on these data, we conclude that 100 mg thymol/kg dietary supplementation increased growth performance of fingerling grass carp. Finally, hepatic adenylate kinase activity was lower in the thymol supplemented group (100 mg/kg feed) than in the control group. Thymol supplementation (100 mg/kg feed) improved hepatic energy metabolism, while practically all tested concentrations of thymol enhanced hepatic antioxidant status, all of which may be pathways involved in increased growth performance in fingerling grass carp.

Consequences of oxidative damage on the fatty acid profile in muscle of Cichlasoma amazonarum acutely exposed to copper.

Rapid industrialization results in the production of large quantities of waste that are commonly discharged into water bodies, leading to the damage of the aquatic ecosystem and freshwater organisms. Copper (Cu) can induce oxidative damage in fish muscle, the main fish portion that is consumed by humans. However, the responses of the Amazon fish Cichlasoma amazonarum and its capacity to withstand acute Cu concentrations found in Amazon water around mines remain unknown. Thus, the aim of this study was to evaluate whether exposure to Cu causes muscle oxidative stress and/or oxidative damage and impairs the fillet fatty acid profile of C. amazonarum acutely exposed to Cu found in Amazon waters around mines. Muscle reactive oxygen species and protein carbonylation levels were significantly higher in fish exposed to 1500 µg/L Cu compared with the control group, while muscle lipid peroxidation levels were significantly higher in fish exposed to 500, 750, and 1500 µg/L Cu compared with control group. Muscle antioxidant capacity against peroxyl radical's levels and glutathione peroxidase activity were significantly lower in fish exposed to 1500 µg/L Cu compared with the control group, while muscle superoxide dismutase activity was significantly lower in fish exposed to 750 and 1500 µg/L Cu compared with control group. The total content of saturated fatty acids was significantly higher in fish exposed to 1500 µg/L Cu compared with the control group, while the total content of monounsaturated fatty acids and sum of n3 fatty acids were significantly lower in fish exposed to 1500 µg/L Cu compared with control group. No significant difference was observed regarding muscle catalase, glutathione S-transferase, and glutathione reductase activities. Based on these lines of evidence, the results of this comprehensive study agree with the initial hypothesis that the exposure to Cu found in Amazon water around mines induces oxidative damage and inhibits enzymatic and non-enzymatic antioxidant response in the muscle of C. amazonarum exposed to high Cu levels. Moreover, the impairment of the fillet fatty acid profile appears to be mediated by oxidative damage, representing a negative impact on fish health.