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.

Fumonisin-(Fusarium verticillioides)-contaminated feed causes hepatic oxidative stress and negatively affects broiler performance in the early stage: Does supplementation with açai flour residues (Euterpe oleracea) minimize these problems?

Fusarium verticillioides is often responsible for contamination of poultry feed with the mycotoxin fumonisin. The aim of this study was to determine whether oxidative stress caused by intake of fumonisin-contaminated feed affects broiler performance at an early stage of development, as well as to test whether the addition of açai residue flour to contaminated feed would minimize these negative effects of redox metabolism. Birds were divided into four groups, with four repetitions of five animals each: control (TC) - birds that received basal feed; TCA treatment - basal feed supplemented with 2% açai flour; TF treatment - feed experimentally contaminated with fumonisin (10 ppm); TFA treatment - fumonisin-contaminated feed (10 ppm) and supplemented with açai fluor (2%). The experiment lasted 20 days, that is, the first 20 days of the chicks' lives. At the end of the experiment, the birds were weighed, and blood, intestine and liver samples were collected. The TCA and TFA had greater body weights and weight gain than did TF. Further, TCA and TFA had lower feed conversion than did TF. Açai flour intake (TCA and TFA) stimulated albumin synthesis and reduced serum AST activity. Nitrate/nitrite (NOx) levels were higher in serum of fumonisin-challenged (TF) birds than in groups; NOx levels were also higher in the livers of all test groups (TF, TCA and TFA) than in TC. Serum glutathione S-transferase (GST) activity was lower in fumonisin-consuming groups (TF and TFA); this was different from what occurred in the liver, that is, higher GST activity in TF and lower activity in TFA than in TC. Catalase activity (CAT) was also higher in the fumonisin-challenged groups (TF and TFA) and the groups supplemented with açai flour (TCA) than in TC. Serum reactive species (RS) and TBARS (lipid peroxidation) levels in the liver were lower in birds supplemented with açai flour and exposed to fumonisin. These data suggest that the addition of açai flour in the feed of early chickens improves animal performance and minimizes the effects of hepatic oxidative stress in birds fed fumonisin-contaminated feed.

Oregano essential oil in the diet of laying hens in winter reduces lipid peroxidation in yolks and increases shelf life in eggs.

We evaluated the effects of oregano essential oil (OEO) added to the feed of semi-heavy laying hens during winter. We measured performance as well as physical and chemical quality of fresh and 21-day stored eggs. A total of 240 semi-heavy laying hens were distributed into six treatments and five replicates (n = 8 each). Treatments consisted of five groups of hens fed diets supplemented with 0, 50, 100, 150 and 200 mg OEO/kg. We measured the average of three productive cycles (1st: week 1-4, 2nd: week 5-8 and 3rd: week 9-12), and found that feed consumption increased in hens in the control group and those in the group treated with 200 mg OEO/kg; other zootechnical variables did not differ between treatments. When we analyzed each individual production cycle individually, we did not observe differences between treatments for the performance variables in the first or second cycles. However, in the third cycle, when the animals were exposed to a greater number of days to cold stress, we recorded improved conversion rate/dozen eggs, conversion rate/daily feed consumed and egg production at T50 (50 mg OEO/kg). Stored eggs from hens supplemented with 50 mg OEO/kg showed lower eggshell percentages and higher yolk pHs. The intensity of the yellow was higher in yolks of the control group and in those from hens supplemented with 200 mg OEO/kg. Lipid peroxidation was lower in fresh egg yolks from hens that received 200 mg OEO/kg and stored eggs of T150. The reduction of lipid peroxidation in egg yolk is beneficial to consumer health by reducing levels of free radicals consumed. Reduction of lipid peroxidation associated with 150 mg OEO/kg in laying hens in winter might be useful for maintaining egg quality and for prolonging shelf life; productive efficiency was improving even at 39.8 mg OEO/kg if we consider feed conversion (kg/kg).

Effect of free and nano-encapsulated curcumin on treatment and energetic metabolism of gerbils infected by Listeria monocytogenes.

Bacterial infections require special care since the indiscriminate use of antibiotics to treat them has been linked to the emergence of resistant strains. In this sense, phytoterapeutic alternatives such as curcumin and its nanocapsules have emerged as a promising supplement in optimizing availability of bioactives and reducing the development of antimicrobial resistance. Thus, the aim of this study was to verify the effects of pure and nanoencapsulated curcumin in the treatment of experimental listeriosis in gerbils regarding many aspects including antibacterial effect, antioxidant mechanisms involved and the energetic metabolism. Four groups were used containing 6 animals each: T0 (control), T1 (infected), T2 (infected and treated with free curcumin - dose of 30 mg/kg/day) and T3 (infected and treated with nanocapsules containing curcumin - a dose of 3 mg/kg/day). Treated animals received curcumin for 6 consecutive days starting 24 h after Listeria monocytogenes infection. All animals were euthanized on the 12th day after L. monocytogenes infection. Quantitative polymerase chain reaction (qPCR) identified L. monocytogenes DNA in the spleens of all animals of the T1 group, as well as T2 (2 out of 6) and T3 (5 out of 6). The weight of the spleens confirmed the infection, since it was larger in the T1 group, differing statistically from T0, and similarly to T2 and T3. Hepatic histopathological examination showed mild infiltration of neutrophils and macrophages, except for the T3 group (only 1/6). In the liver, the pyruvate kinase activity was higher in T1 and T2 compared to T0 and T3. The adenylate kinase activity did not differ between groups. The Na+/K+ATPase activity was lower in T1 group compared to T0 and T3. Lipoperoxidation was lower in the T3 group compared to groups T0, T1 and T2. The antioxidant capacity against peroxyl radicals was higher in T1, T2 and T3 groups compared to T0. In conclusion, free curcumin showed potent antibacterial effects; however, the nanoencapsulated form was able to minimize the effects caused by L. monocytogenes regarding tissue injury, changes on enzymes of the energetic metabolism, in addition to an antioxidant effect against lipoperoxidation.

Addition of grape pomace flour in the diet on laying hens in heat stress: Impacts on health and performance as well as the fatty acid profile and total antioxidant capacity in the egg.

The aim of this study was to evaluate whether the addition of grape pomace flour (GPF) in the diet of laying hens at the end of the productive cycle and on heat stress could exert benefits on their health and performance, as well as egg quality. For this, 74-week-old laying hens (n = 64) were divided into four groups with four repetitions each, as follow: T0 (the control group; without GPF), T1 (1% GPF), T2 (2% GPF) and T3 (3% GPF) during 35 days. Percentage of laid eggs was higher in the group T1 compared to T0, and the feed intake was higher in the groups T1, T2 and T3 compared to T0. There was no difference regarding the chemical-physical composition of fresh eggs; however, eggs from GPF-fed chickens showed changes after storage regarding specific gravity, yolk index, pH of yolk, albumen and Haugh unit compared to T0. Fresh or stored egg yolk from GPF groups showed higher antioxidant capacity and lower lipid peroxidation compared to T0. GPF (3%) prevented the reduction of monounsaturated fatty acids in the yolk of stored eggs compared to T0. Glutathione peroxidase and superoxide dismutase activities, as well as total antioxidant capacity against peroxyl radicals were higher in the serum of laying hens that received GPF compared to T0, while lipid peroxidation was lower. In summary, the addition of GPF in the diet for laying hens at the end of the productive cycle can be beneficial for animal health and exerted positive effects in their performance and egg quality.

Reduction of stool bacterial counts and prevention of diarrhea using an oral homeopathic product in newborn lambs.

Lamb farming is generally a secondary activity for farmers, and many breeding systems suffer from management failures that impair production. One reason for decline in performance is enteritis, usually affecting newborn lambs. Enteritis can be fatal, especially in dairy herds. Generally, lambs are fed sucrose or unprocessed milk from sheep or cow that is heated and fed to animals two or three times a day in baby bottles. However, on most farms, milk temperature differs among feeds, as often the process of alteration among diet adaptations is deficient, contributing to enteritis and consequent diarrhea. Therefore, the objective of the present study was to verify the administration of the homeopathic product (Dia 100®) in newborn and bottle-fed lambs, in order to prevent or minimize the occurrence of diarrhea. We studied 60 lambs, divided into two groups with ten repetitions each (n = 30) and during the nursing period (1-45 days of life). Animals in the treated group received the homeopathic product (36 g) orally divided into three doses (1, 7 and 14 days of life). We measured weight gain, mortality, bacterial counts (Escherichia coli and total coliforms) in feces, hematological analysis (leukocytes, hematocrit, hemoglobin and erythrocytes) and biochemical analyses (glucose, triglycerides, cholesterol, albumin, globulin, urea and total protein) at four time-points. There were no differences in weight gain between groups (P > 0.05); however, there was a higher mortality rate in the control group (13%) than in the treated group (6%). E. coli counts were significantly higher in the stools of control group lambs on days 15 and 45 of the experiment (P < 0.05). Total leukocyte counts were greater in treated animals due to greater numbers of lymphocytes on day 15 of the experiment (P < 0.05). In the treated group, we found higher serum levels of total protein, urea (day 15), globulin and triglycerides (days 15 and 30). In the period of administration of the homeopathic product, there was substantial and significant reduction of cases of diarrhea (up to day 14); however, after this period, there were no difference between groups. Based on these results, we concluded that the homeopathic product had moderate efficacy in terms of control of diarrhea. The treated lambs made better use of nutrients, contributing to the development of their immune responses.

Effects of phytogenic feed additive based on thymol, carvacrol and cinnamic aldehyde on body weight, blood parameters and environmental bacteria in broilers chickens.

The aim of this study was to evaluate whether a phytogenic feed additive (PFA) based on essential oils such as carvacrol, thymol and cinnamic aldehyde, could be considered a replacement for antimicrobials used as growth promoters in broiler chickens, as well as to investigate its effect on total bacterial count, biochemical profiles, meat quality and meat fatty acid profile. A total of 240 broiler chicks were randomly distributed into 4 groups with 4 replicates of 15 animals each, as follow: T1 (basal diet only; the control group), T2 (basal diet supplemented with zinc bacitracin), T3 (basal diet with 0.5% of the PFA), T4 (basal diet with 1.0% of the PFA). The addition of 0.5% of the PFA improved live body weight of supplemented birds compared to the control group at 35 and 42 days of age, while the total bacterial count in the environment was reduced when 1.0% of the PFA was used. In addition, intestinal villi height and crypt depth suffered variations during the entire experiment in birds treated with both concentrations of the PFA and zinc bacitracin. Total erythrocyte counts were higher on days 14, 28 and 42 in both treated groups (PFA) compared to the control group, as well as hemoglobin content on days 28 and 42. On the other hand, leukocyte counts were lower on days 14, 28 and 42 due to reduced lymphocyte counts in both PFA treated groups compared to the control group. Serum levels of alanine aminotransferase (ALT) were lower in broilers fed with either concentration of PFA on day 14 of life, and the same was observed regarding aspartate aminotransferase (AST) in broiler treated with 0.5% of the PFA. Also, total protein and globulin levels were lower on days 14 and 28 in groups fed with phytogenic compared to the control group. Regarding meat quality, breast meat showed higher red intensity and shear force in groups fed with both concentrations of phytogenic compared to the control group, while weight loss by cooking was lower. Finally, 1.0% of phytogenic showed lower docosadienoic acid (C22:2) content in breast meat. In conclusion, results showed that the use of PFAs based on carvacrol and thymol may be considered an interesting alternative to increase broilers performance, replacing the use of antimicrobials as growth promoters, as well as an interesting alternative to reduce the total bacterial count in the environment of broiler chickens. Moreover, the diet containing phytogenic also showed hepaprotective effects but deserves attention regarding possible alterations on the immune response.

Low Dose of Nanocapsules Containing Eucalyptus Oil Has Beneficial Repellent Effect Against Horn Fly (Diptera: Muscidae).

For the first time, the repellent and insecticidal effects of eucalypt essential oil (Eucalyptus globulus) in its free form and associated with different nanostructures (nanoemulsion and nanocapsules) were investigated against Musca domestica (Diptera: Muscidae) and Haemotobia irritans (Diptera: Muscidae) flies. Specimens of M. domestica were collected, separated into groups (n = 10), treated with aspersion of essential oil of eucalypt in its free (1, 5, and 10%) and nanostructured (nanoemulsion or nanoencapsulated at 1, 3, and 5%, respectively) forms. The determination of the insecticidal effect was performed by counting the number of dead flies at intervals of 30, 60, 120, 360 and 750 min after oil aspersion. E. globulus essential oil showed insecticidal effect against M. domestica at concentrations of 1 and 5%. Eucalypt essential oil (10%) caused 100% mortality of M. domestica after 750 min of the treatment. Nanocapsules (3 and 5%) showed efficacy by reducing the number of flies. On the other hand, nanoemulsion did not show insecticidal effect. The repellent action of E. globulus concentrations of 5% was tested against H. irritans on naturally infested cows. The repellent action against H. irritans was verified soon after pulverization. After 24 h, a significant reduction on horn flies' population (83.33 and 66.66%) was observed using free and nanoencapsulated forms tested, respectively. E. globulus essential oil demonstrated insecticidal and repellent effects against M. domestica and H. irritans flies.

Protective effect of nerolidol-loaded in nanospheres against cerebral damage caused by Trypanosoma evansi.

Trypanosoma evansi is a zoonotic parasite associated with high animal mortality that has gained importance due to its capacity to infect humans. Recently, some evidences have demonstrated that T. evansi infection causes severe genotoxic and cytotoxic damage in brain cells, contributing to the pathogenesis and clinical signs of the disease. In this sense, the aim of this study was to evaluate whether nerolidol-loaded in nanospheres, a natural compound with trypanocidal and neuroprotective effects, is able to protect the brain tissue from the cytotoxic and genotoxic effects found during T. evansi infections. Trypanosoma evansi induced brain genotoxic effects through increased damage index (DI) and frequency of damage (FD) when compared to the control group. Moreover, T. evansi induced cytotoxic effects through the reduction of brain cell viability compared to the control group. The metabolites of nitric oxide (NO x ) increased in infected animals compared to the control group. The treatment with nerolidol-loaded in nanospheres prevented the increase on brain DI, FD, and NO x levels, as well as the reduction on cell viability. Based on these evidences, these results confirm that T. evansi induces genotoxic and cytotoxic damage mediated by the upregulation of NO x levels. The most important finding is that nerolidol-loaded in nanospheres was able to prevent DNA damage and cell mortality through the modulation of brain NO x levels. In summary, this treatment can be considered an interesting approach to prevent T. evansi brain damage due its anti-inflammatory property.

Homeopathic treatment as an alternative prophylactic to minimize bacterial infection and prevent neonatal diarrhea in calves.

Bovine neonatal diarrhea is common due low immunity in newborn calves, poor management (or absence) of sanitary barriers, and other factors. Newborn calves with diarrhea in the first days of life suffer failure to thrive and may die if left untreated. The aim of this study was to evaluate whether prophylactic administration of a homeopathic product (Dia 100®) can control bovine neonatal diarrhea in calves born on a farm with substantial sanitary challenges. We counted total bacteria and protozoan parasites in fecal samples. We measured serum glucose, total protein, globulin, albumin, cholesterol and triglycerides on days 1, 7 and 14 of life. Twenty newborn calves were maintained in individual stalls, and were divided in two groups: ten untreated animals (control) and ten animals treated with Dia 100®. Fecal consistency was evaluated daily. We diagnosed diarrhea in five animals in the treated group, and in all animals from the control group. Infections with Escherichia coli and Giardia duodenalis were identified as the responsible organisms. The E. coli count was low in the treatment group on day 7 of life compared with the control group. Antibiotics were given to eight animals in the control group, and to two animals in the treatment group. On day of life 7, serum levels of total protein and globulins were higher in the control group, but were lower on day 14. Serum levels of glucose and triglycerides were greater in treated animals on days 7 and 14, suggesting that the homeopathic product contributes to improvement of intestinal health and absorption and nutrients. We conclude that Dia 100® controls diarrhea with 50% of efficacy, and reduces antibiotic utilization.

Mineralization in newborn calves contributes to health, improve the antioxidant system and reduces bacterial infections.

The first phase of life of dairy calves has elevated mortality indices linked with low immunity and sanitary challenges, mainly bacterial infections are involved in the pathogenesis of diarrhea, the leading cause of death. Also, other important problem is the nutritional deficiencies, such as the mineral deficiency. Thus, the aim of this study was to evaluate whether an intramuscular mineral supplementation based on selenium, copper, potassium, magnesium and phosphorus possess beneficial effects on health of dairy calves. For this, ten calves were divided in two groups: the group A was supplemented with injectable mineral, while the group B was used as control group (without mineral supplementation). The mineral complex was administrated via intramuscularly at dose of 3 mL/animal on days 2 and 14 post-birth. The total blood was collected on days 2, 10, 20 and 30 of life of animals in order to analyze the antioxidant enzymes (catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GPx)), blood count and seric biochemistry linked with proteic, lipid and carbohydrate metabolism. Feces samples were also collected on days 10, 20 and 30 of life of animals to perform the total bacterial count, parasitological exam and fecal consistency score. Moreover, the weight and corporal temperature were also evaluated. The mineral supplementation presented beneficial properties to calves from birth to the 30th of life through the increase on activity of antioxidant enzymes, improvement of immunity, and avoiding problems linked with diarrhea and anemia, can be considered an interesting approach to prevent these alterations linked with high mortality in the period of life.

The use of tucumã oil (Astrocaryum vulgare) in alloxan-induced diabetic mice: effects on behavior, oxidant/antioxidant status, and enzymes involved in brain neurotransmission.

The aim of this study was to investigate the effects of tucumã oil (Astrocaryum vulgare) on memory, enzymatic activities of sodium-potassium pump (Na+, K+-ATPase) and acetylcholinesterase (AChE) in the brain of alloxan-induced diabetic mice. The animals were divided into four groups (n = 6 each): the group A (non-diabetic/water), the group B (non-diabetic/tucumã oil), the group C (diabetic/water), and the group D (diabetic/tucumã oil) treated 14 days with 5.0 mL kg-1 via oral gavage. Untreated diabetic mice (the group C) showed memory deficit, increased levels of thiobarbituric acid reactive species (TBARS) and protein carbonylation (PC), and decreased (p < 0.05) catalase (CAT), superoxide dismutase (SOD), and the Na+, K+-ATPase activities, while acetylcholinesterase (AChE) activity showed a significant increase (p < 0.05) compared to non-diabetic mice (the group A). Tucumã oil prevented these alterations in diabetic mice treated with tucumã oil (the group D) compared to diabetic mice (the group C). Our findings suggest that tucumã oil can modulate cholinergic neurotransmission resting membrane potential of neurons by modulating enzymatic antioxidant defenses. In conclusion, the present data showed that treatment with tucumã oil is beneficial to diabetic mice, demonstrating that this oil can modulate cholinergic neurotransmission and consequently improve or avoid memory deficits.

ß-caryophyllene reduces atherogenic index and coronary risk index in hypercholesterolemic rats: The involvement of cardiac oxidative damage.

Hypercholesterolemia and cardiac oxidative damage have been implicated in the pathophysiology of atherosclerosis. In earlier studies, treatment using natural phytocannabinoid ß-caryophyllene caused a hypolipemic effect, as well as ameliorated hepatic oxidative damage. In this regard, the present study aimed to investigate whether ß-caryophyllene treatment was able to protect the cardiac tissue against hypercholesterolemic atherosclerosis, and to investigate the involvement of antioxidant mechanisms in this effect using a model of hypercholesterolemia induced by Triton WR-1339. The hypercholesterolemic animals exhibited a significant increase in the cholesterol (TC), triglycerides (TG) and free fatty acids (FFA) contents in cardiac tissue, as well as showed significant increase on atherogenic index (AI) and coronary risk index (CRI). Moreover, cardiac levels of reactive oxygen species (ROS) and thiobarbituric acid reactive substances (TBARS) were increased in hypercholesterolemic animals, while the glutathione reduced (GSH) levels and glutathione peroxidase (GPx) activity were decreased. ß-caryophyllene treatment reduced the cardiac lipid content, as well as decreased the AI and CRI. Moreover, the treatment was able to improve the antioxidant/oxidant status in heart tissue of hypercholesterolemic animals. In summary, ß-caryophyllene possesses antioxidant properties, preventing lipidic oxidative damage and ameliorating the GPx activity, an important enzyme linked to the prevention of atherosclerosis. Thus, this compound can be used as an attempt to prevent or reduce atherosclerosis in hypercholesterolemic rats.

Antihyperglycemic, antioxidant activities of tucumã oil (Astrocaryum vulgare) in alloxan-induced diabetic mice, and identification of fatty acid profile by gas chromatograph: New natural source to treat hyperglycemia.

The aim of the study was to investigate the effect of the oral administration of tucumã oil (Astrocaryum vulgare) on glucose and insulin levels, oxidative status, and pancreatic genotoxic parameters of alloxan-induced diabetic mice. The animals were divided into four groups (n = 6 each): control/water; control/tucumã oil; diabetic/water; diabetic/tucumã oil treated for 14 days with 5.0 mL kg-1 via oral gavage. Gas chromatograph characterization demonstrated that oleic/elaidic fatty acid is the most abundant component present in this oil, followed by palmitic and stearic fatty acids. Our results demonstrated an increase (p < 0.05) in water and food intake, blood glucose, thiobarbituric acid reactive species (TBARS) levels, damage index, and frequency of damage; conversely body weight, insulin levels, catalase (CAT) and superoxide dismutase (SOD) activities, and cell viability were decreased in the diabetic/water group compared to the control/water group. The treatment with tucumã oil prevented these alterations in the diabetic/tucumã oil group compared to the diabetic/water group, and restored these parameters near to the control/water group. In summary, our findings demonstrated that treatment with tucumã oil causes a hypoglycemic effect improving insulin levels and antioxidant/oxidant status, and has a protector effect against pancreatic damage induced by oxidative stress in alloxan-induced diabetic mice.

Nerolidol-loaded nanospheres prevent hepatic oxidative stress of mice infected by Trypanosoma evansi.

The aim of this study was to evaluate the effect of nerolidol free (N-F) and nerolidol-loaded in nanospheres (N-NS) on the hepatic antioxidant/oxidant status of mice experimentally infected by Trypanosoma evansi. In the liver it was measured: reactive oxygen species (ROS), thiobarbituric reactive acid substances (TBARS) and non-protein thiols (NPSH), catalase (CAT), superoxide dismutase (SOD) and glutathione-S-transferase (GST) and performed histopathological examination. In addition, seric levels of aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were measured. Liver samples from mice infected by T. evansi showed increased (P < 0·05) ROS, TBARS, AST and ALT levels and SOD activity, and decreased NPSH levels and CAT activity (P < 0·05) compared with uninfected animals. N-NS treatment prevented (P < 0·05) ROS and TBARS increase, and increased NPSH levels, and ameliorate CAT and SOD activities on liver of infected mice. Moreover, N-NS treatment reduced (P < 0·05) AST and ALT levels, and prevented histopathological changes caused by the parasite. N-NS protected the liver from the oxidative stress caused by T. evansi, which might be due to its antioxidant properties. Nerolidol might be considered a promising therapeutic agent against oxidative stress, and nanotechnology is an encouraging approach to be explored.

Melaleuca alternifolia essential oil enhances the non-specific immune system and prevents oxidative damage in Rhamdia quelen experimentally infected by Aeromonas hydrophila: Effects on cholinergic and purinergic systems in liver tissue.

The aim of this study was to evaluate the effects of M. alternifolia essential oil used to treat silver catfish (Rhamdia quelen) experimentally infected by Aeromonas hydrophila on oxidative stress variables, and for the first time, on hepatic enzymes of the cholinergic and adenosinergic systems. For that, fish were divided into six groups (A-F), each containing seven animals. Groups A, B and C were composed of uninfected animals, while animals in groups D, E and F were intramuscularly inoculated with A. hydrophila. Groups B and E received a prophylactic bath with M. alternifolia essential oil (50 µL/L, diluted in ethanol) for seven days, while groups C and F were exposed to ethanol. After the prophylactic baths, groups D, E and F were inoculated with 100 µL of A. hydrophila solution (2.1 × 109 colony-forming unit). Two days after inoculation, the animals were euthanized and liver samples were collected. Infected animals (the group D) showed increased TBARS and protein carbonylation levels, while CAT, AChE and ADA activities decreased compared to uninfected animals (the group A). The prophylactic treatment with M. alternifolia essential oil (the group E) prevented the alterations caused by A. hydrophila, but it did not change AChE activity. Thus, the prophylactic treatment prevents damage caused by lipids and proteins, as well as alterations of the adenosinergic system, demonstrating that the anti-inflammatory effect of TTO is mediated by the adenosinergic pathway. In addition, TTO prophylactic treatment might be considered an important approach to prevent the hepatic damage caused by A. hydrophila.

Achyrocline satureioides essential oil-loaded in nanocapsules reduces cytotoxic damage in liver of rats infected by Trypanosoma evansi.

The aim of this study was to evaluate whether the treatment with Achyrocline satureioides essential oil-loaded in nanocapsules (AS-NC) is able to protect the hepatic tissue against cytotoxic damage caused by Trypanosoma evansi. Thus, the rats were divided into four groups (n = 6 per group): uninfected/saline, uninfected/AS-NC, infected/saline, and infected/AS-NC. At day 4 post-infection (PI), the animals were euthanized and liver and sera samples were collected to perform the hepatic cell viability assay, and to determine seric levels of reactive oxygen species (ROS) and nitric oxide metabolites (NOx). Cell viability decreased (p < 0.05) in the infected/saline group compared to uninfected/saline group, while the treatment with AS-NC avoided this alteration in infected rats. Seric ROS and NOx levels increased (p < 0.05) in the infected/saline group compared to uninfected/saline group, while the treatment with AS-NC avoided this effect on ROS levels of infected rats. In summary, the treatment with AS-NC was able to protect the liver tissue against the cytotoxic effect caused by the parasite by avoiding exacerbated production of ROS.

Melaleuca alternifolia anthelmintic activity in gerbils experimentally infected by Haemonchus contortus.

Gastrointestinal parasites are one of the biggest health problems faced in sheep, mainly due to their pathogenicity and resistance to drugs used to control these parasites. Thus, the following study aimed to assess the anthelmintic efficacy of Melaleuca alternifolia against Haemonchus contortus in gerbils (Meriones unguiculatus) experimentally infected. Three treatments were tested: M. alternifolia essential oil, popularly known as tea tree oil (TTO), a solid lipid nanocarrier made with essential oil of Melaleuca (nanoTTO), and terpinen-4-ol (terp-4-ol). In vivo studies were performed by determining the mean worm burden of H. contortus in gerbils TTO (0.75 mL/kg); nanoTTO (0.5 mL/kg) and terp-4-ol (0.5 mL l/kg) were able to reduce 46.36%; 48.64%, and 43.18% worm burden, respectively. H. contortus increased alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels, as demonstrated by liver injury. It was found that the TTO, nanoTTO, and terp-4-ol were not toxic to liver and kidneys since hepatic and renal functions were not affected. Moreover, terp-4-ol was able to prevent increased levels of seric AST and ALT in infected animals, indicating a hepatoprotective effect. Thus, our results indicate that TTO, nanoTTO, and terp-4-ol are safe and efficient against H. contortus infection in gerbils, and possibly the terp-4-ol may be considered the compound present in the Melaleuca alternifolia responsible for parasitic action against H. contortus.

Experimental infection by Trypanosoma evansi in sheep: Occurrence of transplacental transmission and mice infection by parasite present in the colostrum and milk of infected ewes.

The aims of this study were to evaluate vertical transmission of Trypanosoma evansi in sheep experimentally infected, in addition to the mammary transmission by colostrum or milk of these infected sheep to mice. Three pregnant sheep were used: one uninfected, four months pregnant (Sheep A); and two (Sheep B and C) infected intravenously by T. evansi trypomastigotes (4.6×10(6) per animal) on the third (Sheep C) and fourth (Sheep B) month of pregnancy. Both infected sheep developed low and oscillating parasitemia measured by blood smears. Hemogram was performed at seven day intervals, showing anemia, leukocytosis, and lymphocytosis on sheep B and C. Three sheep had twins, where sheep A delivered healthy lambs and both infected sheep had delivered at least one stillborn. Additionally, lambs from sheep B and C died 24 and 72 h post-partum, respectively. Before colostrum intake, four lambs from infected sheep were positives for T. evansi according to blood smear evaluation, serology (CATT/T. evansi), and PCR. Sheep colostrum and milk samples collected from the first four days post-partum were positives for T. evansi on PCR, and these samples were able to infect seven mice (out of 10) orally (n=4/5) and intraperitoneally (n=3/5). Therefore, we conclude that the vertical transmission of T. evansi occurs in pregnant sheep, in addition to a strong possibility of the transmission by colostrum and milk.

Effects of iron supplementation on blood adenine deaminase activity and oxidative stress in Trypanosoma evansi infection of rats.

The aim of this study was to assess the effects of iron supplementation on oxidative stress and on the activity of the adenosine deaminase (ADA) in rats experimentally infected by Trypanosoma evansi. For this purpose, 20 rats were divided into four experimental groups with five animals each as follows: groups A and B were composed by healthy animals, while animals from groups C and D were infected by T. evansi. Additionally, groups B and D received two subcutaneous doses of iron (60 mg kg(-1)) within an interval of 5 days. Blood samples were drawn on day 8 post infection in order to assess hematological and biochemical variables. Among the main results are: (1) animals from group C showed reduced erythrogram (with tendency to anemia); however the same results were not observed for group D; this might be a direct effect of free iron on trypanosomes which helped to reduce the parasitemia and the damage to erythrocytes caused by the infection; (2) iron supplementation was able to reduce NOx levels by inhibiting iNOS, and thus, providing an antioxidant action and, indirectly, reducing the ALT levels in groups Band D; (3) increase FRAP levels in group D; (4) reduce ADA activity in serum and erythrocytes in group C; however, this supplementation (5) increased the protein oxidation in groups B and D, as well as group C (positive control). Therefore, iron showed antioxidant and oxidant effects on animals that received supplementation; and it maintained the activity of E-ADA stable in infected/supplemented animals.