Different effects of whitening treatment on natural teeth and teeth treated with Icon resin: an experimental study in vitro

BACKGROUND

It is quite common for white spots to develop on a tooth, due sometimes to a defective formation of the enamel layer, and sometimes to patches of demineralisation as a result of poor oral hygiene during orthodontic treatment with fixed braces. ICON DMG is currently the only noninvasive treatment for white spots. After a preliminary etching, it infiltrates the enamel, filling the spaces between the prisms with a resinous material that has a refraction coefficient very similar to that of healthy tooth enamel. The aim of this study was to test the efficacy of professional whitening procedures on teeth previously treated with ICON. The study hypothesis was that infiltration with ICON resin creates a barrier capable of preventing the bleaching action of the whitening agent.

MATERIALS

White spots were artificially created on one half of the vestibular surface of 12 human teeth, while the other half was protected with a composite adhesive. The white spots were infiltrated with ICON and the protective adhesive was subsequently removed. A professional teeth whitening procedure was then completed on both halves of the teeth. A statistical analysis was performed to compare spectrophotometric recordings obtained before and after the ICON infiltration and teeth whitening procedures.

CONCLUSION

The whitening procedure modified the colour of the teeth on the half not infiltrated with ICON (p<0.05), but there was no statistically significant change in colour on the half infiltrated with ICON. The presence of the ICON resin seems to act as a partial barrier to the action of the whitening agent.

Dietary addition of curcumin favors weight gain and has antioxidant, antiinflammatory and anticoccidial action in dairy calves

Background: Curcumin has been used as an additive in the diet of animals in recent years due to the potent medicinal properties of this molecule. Objective: To evaluate whether the addition of curcumin to the diet of calves at different phases (pre- and post-weaning) has a positive effect on metabolic profile, performance, and anti-coccidian action. Methods: Thirtythree Holstein calves were selected at various phases of development: Experiment 1 (E1: n=10) 18±7 (pre-weaning), Experiment 2 (E2: n=11) 64±4 (pre-weaning) and Experiment 3 (E3: n=12) 95±8 (post-weaning) days of life. The calves were separated in three groups according to their phase of development. In each experiment, animals were divided into two sub-groups: control and curcumin. The curcumin groups received 200 mg of additive per animal/day either in milk (pre-weaning) or concentrate (post-weaning). Fecal collections were performed on days 0, 10 and 15 of the experiment to count Eimeria oocysts per gram of feces and to perform fecal score analysis. Complete blood counts, oxidant and antioxidant profiles, protein metabolism markers, lipid levels, glucose levels, and animal weights were measured. Analyses of digestibility and composition of the diet used in Experiment 3 (post-weaning) were also performed. Results: Independent of phase, animals that received curcumin had greater weight gain on days 0 to 15 (E1, E2 and E3 p=0.04, 0.001 and 0.001, respectively), probably due to the increased digestibility of hay and concentrate at 72h (p=0.03 and 0.02, respectively). The supplemented calves had lower level of oxidants (thiobarbituric acid reactive substances –TBARS- and reactive oxygen species –ROS-), indicating that free radical levels in serum and lipid peroxidation were lower. This was probably due to increased enzymatic antioxidants gluthatione S-transferase (E1, E2 and E3 p=0.001, 0.001 and 0.02, respectively), catalase (E1 p=0.001) and superoxide dismutase (E3 p=0.001) in treated animals at day 15. Furthermore, calves receiving curcumin had lower numeric number of Eimeria infection during the experimental period, and the difference was significant in day 15 (E1 and E2 p=0.02, and 0.001, respectively). Conclusion: Curcumin supplementation to dairy calves has coccidiostatic potential, favoring weight gain.Keywords: animal stress; antioxidants; calves; cattle growth; curcumin; Eimeria; parasitology; supplementation.  Resumen Antecedentes: Curcumina ha sido utilizada como aditivo en la dieta de animales en los últimos años, debido a las potentes propiedades medicinales de esa molécula. Objetivo: Evaluar si la adición de curcumina en la alimentación de terneras en diferentes fases (pre y post-destete) presenta efecto positivo sobre el perfil metabólico, desempeño de los animales, y acción anti-coccidial. Métodos: Se seleccionaron 33 terneros Holstein en varias etapas de desarrollo: Experimento 1 (E1: n=10) 18±7 (pre-destete), Experimento 2 (E2: n=11) 64±4 (pre-destete) y Experimento 3 (E3: n=12) 95±8 (post-destete) días de vida. Para todos los experimentos, el período experimental fue de 15 días. Los animales se dividieron en dos grupos: control y tratados con curcumina. Los grupos con curcumina recibieron una dosis de 200 mg del aditivo por animal/día en la leche (pre-destete) o en el concentrado (post-destete). Las colectas de heces y sangre fueron realizadas en los días 0, 10 y 15 para conteo de ooquistes de Eimeria por gramo de heces y análisis de puntaje fecal. Se realizó hemograma, perfil oxidante y antioxidante, metabolismo proteico, lipídico, glucosa sanguínea y pesaje de los animales. También se realizó análisis de digestibilidad de la dieta total para los animales del Experimento 3 (post-destete). Resultados: Encontramos que, independientemente de la fase, los animales que recibieron curcumina tuvieron una mayor ganancia de peso en los días 0 a 15 (E1, E2 y E3, p=0,04, 0,001 y 0,001, respectivamente), probablemente debido al aumento de la digestibilidad del heno y concentrado a las 72 h (p=0,03 y 0,02, respectivamente). En los terneros suplementados observamos un nivel más bajo de oxidantes (oxidantes (sustancias reactivas al ácido tiobarbitúrico y especies reactivas de oxígeno); es decir, los niveles séricos de radicales libres y la peroxidación lipídica fueron más bajos. Esto se debió, probablemente, a los antioxidantes enzimáticos glutatión S-transferasa (E1, E2 y E3 p=0,001, 0,001 y 0,02 respectivamente), catalasa (E1, p=0,001) y superóxido dismutasa (E3, p=0,001) que aumentaron en los animales tratados al día 15. Además, los terneros que recibieron curcumina tuvieron niveles más bajos de infección por Eimeria durante el período experimental y fueron significativos en el día 15 (E1 y E2, p=0,02 y 0,001, respectivamente). Conclusión: La suplementación con curcumina tiene potencial coccidiostático y favorece la ganancia de peso en terneros Holstein. Palabras clave: antioxidantes; crecimiento de ganado; curcuminatiene; Eimeria; estrés animal; parasitología; suplementación; terneros.  ResumoAntecedentes: Curcumina tem sido usado como aditivo na dieta de animais nos últimos anos, devido as propriedades medicinais potente dessa molécula. Objetivo: Avaliar se a adição de curcumina na alimentação de bezerras em diferentes fases (pré e pós-desmame) apresenta efeito positivo sobre perfil metabólico, desempenho e ação anti-coccidéo. Métodos: Para isso, 33 bezerros holandeses foram selecionados em vários estágios de desenvolvimento: Experimento 1 (E1: n=10) 18±7 (prédesmame), Experimento 2 (E2: n=11) 64±4 (pré-desmame) e Experimento 3 (E3: n=12) 95±8 (pós-desmame) dias de vida. Para todos os experimentos o período experimental foi de 15 dias, assim como foram delineados com dois grupos: controle e tratados com curcumina. Os grupos de curcumina receberam 200 mg do aditivo por animal/dia no leite (pré-desmame) ou em concentrado (pós-desmame). Coletas de fezes e sangue foram realizadas nos dias 0, 10 e 15 de experimento para contagem de oocistos de Eimeria por grama de fezes e análise de escore fecal. Do sangue colhido foram realizados: hemograma, perfil oxidante e antioxidante, metabolismo proteico, lipídico, glicose, além da pesagem dos animais. Também foi realizado análise de digestibilidade da dieta total ofertada aos animais do Experimento 3 (pós-desmame). Resultados: Independentemente da fase, os animais que receberam curcumina tiveram maior ganho de peso do dia 0 a 15 (E1, E2 e E3, p=0,04, 0,001 e 0,001, respectivamente), provavelmente devido ao aumento da digestibilidade ao feno e concentrado após 72 h (p=0,03 e 0,02, respectivamente). Nos bezerros suplementados, observou-se menor nível de oxidantes (substâncias reativas ao ácido tiobarbitúrico e espécies reativas de oxigênio), ou seja, os níveis séricos de radicais livres e a peroxidação lipídica foram menores. Isto foi provavelmente devido a antioxidantes enzimáticos glutationa S-transferase (E1, E2 e E3, p=0,001, 0,001 e 0,02, respectivamente), catalase (E1, p=0,001) e superóxido dismutase (E3, p=0,001) aumentando nestes animais tratados no dia 15. Além disso, bezerros recebendo curcumina tiveram menores níveis de infecção por Eimeria durante o período experimental e significativos no dia 15 (E1 e E2, p=0,02 e 0,001, respectivamente). Conclusão: A suplementação de curcumina aumenta o potencial coccidiostático e favorece o ganho de peso.Palavras-chave: antioxidante; bezerros; crescimento do gado; curcumina; Eimeria; estresse animal; parasitologia; suplementação.

Efeitos da ingestão diária de leite in natura produzido por vacas criadas em diferentes sistemas de menejo sobre variáveis sanguíneas, saúde intestinal e ganho de peso em um modelo animal

O objetivo do presente estudo foi avaliar se o leite de vaca produzido em diferentes sistemas (confinamento ou a pasto) quando consumido interfere em parâmetros sanguíneos e saúde intestinal, assim como a importância do consumo leite diária no crescimento do animal, modelo experimental. Para isso, foram utilizados leite in natura oriundo de duas propriedades com diferentes sistemas de criação (Free Stall – confinado; extensivo - a pastagem) comparado ao leite pasteurizado (UHT), usado como controle. A composição centesimal dos leites foi analisada, separado em alíquotas e posteriormente congelado. 28 ratos foram usados como modelo experimental (modelo animal), por um período de 30 dias, sendo estes divididos em quatro grupos com sete animais cada: leite das vacas criadas no sistema Free Stall (GFS), leite das vacas criadas no sistema a pasto (GP), leite das vacas pasteurizado (GUHT), e animais sem consumo de leite (GC). Volume de 0,7 mL de leite foi oferecido diariamente. Quando comparado ao grupo controle (GC) verificamos diferença (P0.05), no entanto, o tamanho de cripta foi maior nos grupos GP e GFS (P

Nutraceutical effect of vitamins and minerals on performance and immune and antioxidant systems in dairy calves during the nutritional transition period in summer

We aimed to determine whether the use of injectable vitamins and minerals improves growth performance and immune and antioxidant responses in dairy calves during pre- and post-weaning period in summer. Twenty dairy calves (45 days of age) were randomized to two groups (10 each): control group (CON) and treated group [TREAT; injection providing 0.20, 0.80, 0.20, 0.10, 35 and 1 mg/kg of copper, zinc, manganese selenium, and vitamins A and E, during two periods (15 days pre- and 15 days post-weaning)]. The animals were weighed and blood samples were collected on days 1, 15, 30 and 45 of the study. Levels of serum copper, selenium, zinc, and manganese were measured on day 1; and the results showed that calves were not deficient in these minerals. The TREAT group had greater BW gain during the final third of the experiment. There was an increase in total leukocyte numbers as a result of elevation in neutrophil counts (day 45) and monocytes (days 30 and 45) in the TREAT group. This group also had lower reactive oxygen species (ROS) content (days 15, 30 and 45) and lipid peroxidation (LPO; days 15 and 45). Furthermore, the TREAT group had greater antioxidant capacity against peroxyl radicals (ACAP; days 15 and 30), activities of the enzymes glutathione peroxidase (GPx; days 15, 30 and 45) and superoxide dismutase (SOD; day 15), concentrations of total serum proteins (day 30), serum globulin (days 15 and 30), ceruloplasmin (day 15), tumor necrosis factor-alpha (TNF-α), interleukin-1, (IL-1; days 30 and 45) and interferon gamma (IFNγ; day 45), compared to CON group. High respiratory rates during hot times of the day in all study calves was suggestive of heat stress. Taken together, the data suggest that mineral and vitamins injections increased the growth performance and boosted the antioxidant and immunological systems of dairy calves during the diet transition period in summer.

Low-dose curcumin-loaded Eudragit L-100-nanocapsules in the diet of dairy sheep increases antioxidant levels and reduces lipid peroxidation in milk

The main objective of this study was to evaluate whether the addition of curcumin-loaded nanocapsules (prepared and characterized) in the diets of dairy sheep improved milk quality. The nanocapsules were prepared using two polymers: poly-ε-caprolactone (PCL) and Eudragit L-100. The nanocapsules contained 0.25 mg/ml (Nano-Eudragit L-100) and 2 mg/ml (Nano-PCL) of curcumin. Dairy sheep were divided into four groups: A (control), B (30 mg free curcumin/kg concentrate), C (3 mg Nano-PCL/kg concentrate), and D (3 mg Nano-Eudragit/kg concentrate). We observed that the number of total leukocytes and serum globulin levels were lower in Group D than in the control (Group A) (p < 0.05). Antioxidant capacity against peroxyl radicals (ACAP) and catalase enzymes was elevated in Group D, with consequently reduced lipid peroxidation (LPO; p < 0.05). In milk, there were no differences in production and composition between groups during the experimental period (p > 0.05); however, ACAP increased and LPO decreased in milk. PRACTICAL APPLICATIONS: Curcumin is a functional molecule with potent antioxidant, anti-inflammatory, and antimicrobial actions, used frequently and with medical indications in human food. Free curcumin in sheep diets improves milk quality and increases its shelf life. This study showed that curcumin nanocapsules produced from the Eudragit L-100 polymer potentiated the anti-inflammatory and antioxidant actions of dairy sheep when used in the diet daily, at doses 10 times lower than that of free curcumin. These positive effects were reflected in higher total antioxidant capacity and lower lipid peroxidation in milk in sheep-fed curcumin-loaded Eudragit L-100 nanocapsules, generating desirable milk properties. In practice, the use of nanotechnology enhances the beneficial effects of curcumin in milk, possibly creating a nutraceutical food desirable to consumers.

Effects of tannin-containing diets on performance, gut disease control and health in broiler chicks

The emergence of antibiotic-resistant bacteria in the intestinal microbiota of broiler chickens, and the possibility of antibiotic residues in meat and meat products are seen as a threat to animal and human health. The search for alternatives to conventional drugs, including natural compounds, is an interesting approach to prevent the adverse effects of antibiotics. Therefore, the aim of the present study was to evaluate whether the addition of tannin (as a quebracho extract) in the diet of broiler chickens could be used to replace in-feed antimicrobials and coccidiostatic drugs, to exert positive effects on animal health and performance. The use of tannin in the diet of broiler chicks as an additive (at 0.5% for 1–10-day-old birds; and 1.0% for 11–42-day-old broiler chickens) enhanced their bodyweight, weight gain and daily weight gain on Day 42 of life, compared with the untreated control group (P &lt; 0.05). However, these findings were not observed when tannin was added at 0.5%. Moreover, broiler chickens fed with an extract containing tannins showed higher erythrocyte counts, as well as haemoglobin and haematocrit concentrations than did those in the control group, whereas counts of total leukocytes and lymphocytes were lower (P &lt; 0.05). The use of a diet with tannins did not influence meat quality compared with a diet containing zinc bacitracin and salinomycin, which altered some parameters associated with meat colour. Moreover, the diet with tannins reduced (P &lt; 0.05) the number of oocysts of Eimeria sp. (36-day-old broilers) and the total faecal bacterial counts (42-day-old broilers) compared with the control group. Finally, intestinal histopathology showed that the addition of tannins minimised the degree of lesions (Degree 1) compared with the control group (Degree 3). On the basis of these results, we concluded that the use of quebracho extract containing tannins can be a suitable approach to improve the performance of broiler chickens, replacing in-feed antibiotics and coccidiostatic drugs. The use of tannins did not change meat quality; however, it caused positive effects on the immune system, and exerted potent bactericidal and coccidiostatic properties, reinforcing its use as a replacement for conventional drugs.

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.

AVALIAÇÃO IN VITRO DOS EFEITOS INSETICIDA E LARVICIDA DE OITO ÓLEOS ESSÊNCIAIS SOBRE O CASCUDINHO AVIÁRIO (Alphitobius diaperinus)

Alphitobius diaperinus, popularmente conhecido como o cascudinho de aviário, é um inseto que se destaca na avicultura por ser vetor de patógenos e de difícil controle. Esta dificuldade está relacionada à contra-indicação na utilização de produtos químicos, já que enquanto as aves estão no aviário, grandes prejuízos podem ocorrer em consequência de elevadas infestações. Portanto, produtos naturais com potencial inseticida e larvicida poderiam ser usados, sem prejudicar as aves e sem deixar resíduo na carne do frango. Em virtude disso, neste estudo objetivou-se verificar o efeito dos óleos de Capim limão (Cymbopogon citratus), Cedro (Cedrus atlantica), Gengibre (Zingiber officinale), Gerânio (Pelargonium graveolens), Junípero (Juniperus communis), Palmarosa (Cymbopogon martinii), Tomilho (Thymus vulgaris) e Vetiver (Vetiveria zizanioides) sobre a suscetibilidade de A. diaperinus. Os testes foram realizados em triplicata com os óleos essenciais nas concentrações de 1, 5 e 10%. A fim de validar os testes, foram utilizados dois controles: sem tratamento e com diluente (Triton). O efeito inseticida do óleo de Capim limão não foi satisfatório, pois a mortalidade superior a 50% foi atingida 15 dias após início do teste. O óleo de Cedro não demostrou efeito significativo sobre adultos e larvas, pois os valores de mortalidade foram inferiores a 50% em todas as concentrações avaliadas. Os efeitos inseticidas e larvicidas não foram observados nos demais óleos nas concentrações testadas neste experimento (P>0,05).  Portanto, com base nos resultados dos testes in vitro podemos concluir que os óleos testados neste trabalho não apresentam efeitos inseticidas e larvicidas nas concentrações testadas, sobre A. diaperinus e, com isso, são inadequados para o controle alternativo desta praga.

A prophylactic protocol to stimulate the immune response also controls infectious disease and, consequently, minimizes diarrhea in newborn heifers

The immunostimulatory and immunomodulatory properties of selenium (Se), an essential trace element for animals, has increase its use because may prevent/or reduce the occurrence of infectious diseases. Thus, the aim of this study was to verify whether Se and vitamins (A and E) applied via subcutaneous associated with secnidazole via oral exert positive effects in the antioxidant and immune systems, as well as whether prevent infections caused by protozoan and bacteria, and consequently, reduce the number of cases of diarrhea in heifers. Thirty-two newborn Holstein heifers were divided into two groups with sixteen animals each: the control group and the treated group that received sodium selenite (0.2 mg/kg) and vitamins A (35 mg/kg) and E (1 mg/kg) with one day of life, and a second application associated with secnidazole (400 mg/animal) on day 10 of life. Sample collection (blood and feces) were performed on days 1, 15, 30, 45 and 60 of life. Heifers from the treated group showed higher hematocrit values compared to the control group on day 60 of life, while total serum protein levels were higher on days 15 and 30. The ceruloplasmin (days 15, 30 and 60), IgG of heavy chain (days 15, 30, 45 and 60), IgG of light chain (days 45 and 60) and haptoglobin (days 15, 30, 45 and 60) were higher in the treated group compared to the control group. Serum levels of glucose decreased in treated animals on day 60 of life, while serum levels of albumin, triglycerides, urea, cholesterol, thiobarbituric acid reactive substances, reactive oxygen species and glutathione S-transferase activity did not differ between groups. Secnidazole was able to prevent infections caused by Giardia duodenalis in the first few days of life, but no difference was observed between groups. Moreover, there was no difference on total bacteria count and the incidence of diarrhea between groups. No difference on weight gain was observed on day 60 of life, but on day 210 of life treated animals had higher weight gain compared to the control group. Based on these evidences, we concluded that the injectable application of Se and vitamins (A and E) associated to secnidazole can improve the immunological system, and consequently, favor animal's performance.

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.

The Protective Effects of an Adsorbent against Oxidative Stress in Quails Fed Aflatoxin-Contaminated Diet

Background: Contamination of crops with aflatoxin is considered a serious global threat to food safety, since potent carcinogenic, teratogenic, mutagenic and immunosuppressive effects of aflatoxins are well recognized. Recently, the use of adsorbents has been linked with protective effects against oxidative stress in several diseases. Thus, the aim of this study was to assess the occurrence of oxidative stress in quails (Coturnix coturnix) fed with aflatoxin-contaminated diet, as well as the protective effect of an adsorbent.Materials, Methods & Results: Twenty-eight quails were divided into four groups (n = 7): diet without additives (control; the group A), diet and adsorbent containing aluminosilicates (the group B), aflatoxin-contaminated diet (200 ppb) (the group C), and aflatoxin-contaminated diet (200 ppb) and adsorbent containing aluminosilicates (the group D). The composition of the adsorbent containing aluminosilicates was 0.3% based on yeast cell wall, silymarin, and bentonite. The animals received feed and water ad libitum during 20 days. At the end of the experimental period, total blood was collected by cardiac puncture in tubes without anticoagulant to obtain serum (centrifuged at 3500 g during 10 min) for later determination of biochemical parameters. The liver was placed in a solution of Tris–HCl 10 mM, pH 7.4 for TBARS (Thiobarbituric acid reactive substances), ROS (Reactive oxygen species), SOD (Superoxide dismutase) and CAT (Catalase) analysis. The hepatic tissue was gently homogenized in a glass potter in specific buffer, homogenated, and centrifuged at 10.000 g at 4ºC for 10 min to yield a supernatant (S1) used for analyses. Homogenate aliquots were stored at -80°C until utilization. Fragments of liver and intestine (5 cm) were collected for histopathological analyses. Between days 15 to 20 of the experiment, group C quails showed clinical signs, such as apathy, creepy feathers and reduced feed intake. At day 20 of experiment, macroscopically, the liver of quails belonging to the group C showed greenish yellow color differently from the other groups. Microscopically, no alterations were observed in the liver of animals in groups A and B. Severe diffuse microvacuolar degeneration (hydropic) of hepatocytes and small foci of necrosis in the liver were observed in the group C, as observed in the group D, but in a more moderate degree to microvacuolar degeneration. Seric total protein, albumin, globulin and uric acid levels decreased in the group C and D. The levels of alanine aminotransferase (ALT) increased in the group C, and the treatment with adsorbent was able to avoid this increment. Seric and hepatic reactive oxygen species and TBARS increased in the group C, and the treatment with adsorbent reduced theses parameters in the group D. Catalase (CAT) activity decreased, while ALA-D increased in the group C. The treatment with adsorbent was able to prevent CAT activity decrease, but it did not prevent the increase in ALA-D activity.Discussion: Aflatoxins are considered one of the most important problems in poultry production causing high economic losses to producers. In this study, the use of adsorbent showed a protective effect to hepatic tissue, minimizing histopathological lesions, as well as by preventing lipid peroxidation and exacerbated production of free radicals. Based on this data, aflatoxin intoxication causes hepatic oxidative stress that contributes directly to disease pathogenesis, and the addition of an adsorbent containing 0.3% based on bentonite, yeast cell wall and silymarin may be considered a new approach to prevent cellular and hepatic damage caused by aflatoxins.

Gastrointestinal protozoa in dairy calves: identification of risk factors for infection

Objective. This study aimed to evaluate the occurrence of gastrointestinal protozoa in dairy calves and to identify potential risk factors for this type of infection. Materials and methods. For this purpose, 243 fecal samples were collected from calves up to 60 days of age in 43 dairy farms located in the West region of Santa Catarina state, Brazil. Samples were examined by centrifugal-flotation technique. Results. As a result, Giardia was present in 26.75% (65/243) of all samples, Eimeria in 21.81% (53/243), and Cryptosporidium in 20.99% (51/243). Additionally, 46.50% (113/243) of the samples were negative for any protozoa, while 39.10% (95/243) and 14.40% (35/208) showed single and mixed infections, respectively. There was a higher association between Cryptosporidium and Giardia (6.99%) in cases of mixed infections. However, the triple protozoa association had the lowest prevalence in mixed infections (2.06%). Epidemiologically, a questionnaire was applied to determine risk factors for these parasitic infections. Based on the statistical model applied, some risk factors for Cryptosporidium infections were identified, highlighting feeding management, period of time that calves stayed with their mothers (cows), and contact with dogs; the risk of contracting Giardia increased according to the milk source, while the floor type bedding, and age were appointed as risks factors for Eimeria. Conclusions. Therefore, it is possible to confirm that Giardia, Cryptosporidium and Eimeria may infect dairy calves, and the knowledge of some risk factors associated to their infection in calves.

Ecotoxicology of Glycerol Monolaurate nanocapsules

Glycerol Monolaurate (GML) is a compound with known antimicrobial potential, however it is not much used due to its low solubility in water and high melting point. The nanoencapsulation of some drugs offers several advantages such as improved stability and solubility in water. The present study aimed to produce, characterize, and evaluate the ecotoxicity of GML nanocapsules. The nanocapsules were produced and presented a mean diameter of 210nm, polydispersity index of 0.044, and zeta potential of -23.4mV. The electron microscopy images showed the nanometric size and spherical shape. The assay in soil showed that GML has a high toxicity while the GML nanocapsules showed decreased toxic effects. Nanostructuration also protected the Rhamdia quelen against the toxic effects of GML. Concluding, the formulation shows positive results and is useful to predict the success of development besides not damaging the soil.

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.

In vitro repellent effect of tea tree (Melaleuca alternifolia) and andiroba (Carapa guianensis) oils on Haemotobia irritans and Chrysomya megacephala flies

This study aimed to evaluate the repellent effect of tea tree (Melaleuca alternifolia) and andiroba (Carapa guianensis) essential oils on two species of flies (Haemotobia irritans and Chrysomya megacephala). For the in vitro studies, free-living adult flies were captured and reared in the laboratory. To verify the repellency effect, an apparatus was constructed where H. irritans and C. megacephala were exposed to andiroba and tea tree oils (5.0%), as well as to a known repellent (citronella, 5.0%) to validate the test. The study demonstrated that all three oils used showed in vitro repellent effect against both species of flies. It is possible to conclude that the essential oils (tea tree and andiroba) have repellent effect on these species of flies used in this study.

Trichostrongylus and Haemonchus anthelmintic resistance in naturally infected sheep from southern Brazil

The anthelmintic resistance in small ruminants is a common problem and concern worldwide. The aim of this study was to verify anthelmintic treatment efficacy in naturally infected sheep. This study was conducted on nine herds that used the same anthelmintic management for over a year. In each farm, the animals were divided into two groups: untreated control group (n = 5) and treated (n = 10) according to the number of eggs per gram of feces (EPG). The treatment effect was checked based on EPG results and larval culture performed before treatment and 10 days after treatment. Significant differences were not observed (P > 0.05) on EPG results between untreated and treated groups. The coproculture showed that the animals were infected primarily by Haemonchus spp., Trichostrongylus spp., Teladorsagia spp., Cooperia spp. and Oesophagostomum spp. In all farms, anthelmintic resistance by genera Haemonchus and Trichostrongylus was found, but this resistance varied greatly between farms. Haemonchus spp. showed resistance to closantel, levamisole, and albendazole. Trichostrongylus spp. was shown to be resistant to closantel, levamisole, and albendazole. The drugs tested showed to be efficient against the genera Teladorsagia, Cooperia, and Oesophagostomum. Based on these results, we conclude that the anthelmintic resistance to the tested drugs is a problem present in the farms evaluated.

Influence of tea tree oil (Melaleuca alternifolia) on the cattle tick Rhipicephalus microplus

The aim of this study was to verify the influence of tea tree oil (TTO) (Melaleuca alternifolia) tested in its pure and nanostructured (TTO nanoparticles) forms on the reproduction of female Rhipicephalus microplus. For our purpose, female ticks were collected from naturally infected animals and treated in vitro with TTO (1, 5, and 10 %) and TTO nanoparticles (0.075, 0.375, and 0.75 %). In order to validate the tests, they were performed in triplicate using positive (amitraz) and negative (untreated) controls. It was possible to observe that pure TTO (5 and 10 %) and TTO nanoparticles (0.375 and 0.75 %) showed 100 % reproductive inhibition on female ticks. Additionally, pure TTO (1 %) also showed an acaricide effect (70 %), similarly to the positive control (78.3 %). This is the first study demonstrating the activity of pure TTO and TTO nanoparticles on female ticks. Therefore, based on these results, we were able to show that both forms and all concentrations of M. alternifolia affected tick reproduction by inhibiting egg laying and hatching. We were also able to show that TTO nanoparticles potentiated the inhibitor effect of pure TTO on the reproduction of R. microplus.