Abstract: The aims of this study were to investigate whether treatments with zinc edetate (Zn) and diphenyl diselenide ((PhSe)2) enhance performance, immune responses, protein metabolism, and oxidant/antioxidant status in calf serum and muscle. Animals were divided into four groups (n=6 each): control (without supplementation), and groups supplemented on days 50 and 70 of life with (PhSe)2, Zn, and a combination of (PhSe)2 and Zn. Animals treated with (PhSe)2 gained more weight by experimental day 220 than did the control group, but there was no difference by the end of the experiment (day 300). The absolute number of leukocytes and lymphocytes increased in groups Zn and (PhSe)2+Zn on day 20 of experiment, but decreased on day 40 in groups (PhSe)2, and (PhSe)2+Zn. The number of monocytes decreased in all groups compared with control. One of the principal findings was that (PhSe)2+Zn together had beneficial effects on protein metabolism, represented by increases total protein and globulin levels, compared with the control group. The combination of (PhSe)2 and Zn led to low levels of TBARS and ROS in serum and muscle, and stimulated antioxidant enzyme activities. Thus, supplementation with (PhSe)2+Zn may be a compelling approach to augmenting the calf antioxidant system during weaning.

Resumen Objetivo. Debido a la mayor resistencia parásita, hay una necesidad de explorar insecticidas alternativos, incluidos los productos naturales, tales como aceites esenciales. En este sentido, el objetivo de este estudio fue evaluar, para el primer equipo, el efecto insecticida y repelente de Cinnamomum zeylanicum (formas libres y nanoemulsión) in vitro e in vivo. Materiales y métodos. Para ello, el efecto insecticida de la forma libre se ensayó a 1.0, 5.0 y 10%, mientras que la forma nanoemulsión se ensayó a 0.5, 1.0 y 5.0% frente a las moscas domésticas adultas, Musca domestica. Para la validación de la prueba, las moscas fueron rociados con el diluyente (agua y triton 10%) y con nanoemulsión en blanco (sin aceite esencial de C. zeylanicum). También, fueron realizados pruebas in vivo usando vacas naturalmente infestadas con Haemotobia irritans. Resultados. Los resultados demostraron que el aceite de canela (10%) y la nanoemulsión (5%) fueron 100% eficaz contra M. domestica después de 90 minutos de exposición. El efecto repelente se ensayó in vivo usando 5% de aceite de canela en vacas Holstein, naturalmente infestados por Haemotobia irritans. Se contaron las moscas a las 0, 1, 2, 3, 9 y 24 h después del tratamiento el aceite de canela. Se verificó disminución significativa (p<0.05) en el número de moscas vivas de vacas canela pulverizada en todo momento. Conclusiones. En base a estos resultados, C. zeylanicum mostró un efecto insecticida (in vitro) contra las moscas domésticas y efecto repelente (in vivo) contra la mosca de los cuernos.

Abstract Objective. Due to the increased parasitic resistance, there is a need to explore alternative insecticides, including natural products, such essential oils. In this sense, the aim of this study was to evaluate, for the first time, the insecticidal and repellent effect of Cinnamomun zeylanicum (free and nanoemulsion forms) in vitro and in vivo. Materials and methods. For that, the insecticidal effect of the free form was tested at 1.0, 5.0 and 10%, while the nanoemulsion form was tested at 0.5, 1.0 and 5.0% against adult house flies, Musca domestica. For validation of the test, the flies were sprayed with the diluent (water and triton 10%) and with blank nanoemulsion (without C. zeylanicum essential oil). Moreover, in vivo test was performed using cows naturally infested with Haemotobia irritans. Results. The results demonstrated that cinnamon oil (10%) and the nanoemulsion (5%) were 100% effective against M. domestica after 90 minutes of exposure. The repellent effect was tested in vivo using 5% of cinnamon oil on Holstein cows naturally infested by Haemotobia irritans. The flies were counted at 0, 1, 2, 3, 9 and 24 h after cinnamon oil treatment. It was verified significant decrease (p<0.05) in the number of flies on cows sprayed with cinnamon in all times. Conclusions. Based on these results, C. zeylanicum showed insecticidal effect (in vitro) against domestic flies and repellent effect (in vivo) against the horn fly.

RESUMEN Objetivo. El objetivo de este estudio fue evaluar la influencia de la suplementación subcutánea con diselenuro de difenilo (PhSe)2 en ovejas lecheras infectadas con nematodos sobre la salud animal y posible daño al ambiente cuando las heces de estos animales se utilicen para fertilizar. Materiales y métodos. El experimento se realizó utilizando 16 ovejas lecheras, que se dividieron en dos grupos: el grupo A se usó como control y el grupo B se suplementó con 3 µmol/kg of (PhSe)2 vía subcutánea. Se utilizaron muestras de sangre para determinar la función hepática, así como el metabolismo de proteínas y lípidos en animales. Las heces se utilizaron para determinar el número de huevos por gramo de heces (EPG), así como para las pruebas de ecotoxicología. Resultados . La suplementación (PhSe)2 no afectó la reproducción de helmintos. Los niveles totales de proteína y globulina aumentan (p<0.05) en los animales suplementados, mientras que los niveles séricos de alanina aminotransferasa (ALT) disminuyen (p<0.05) al final del diseño experimental. Los niveles de colesterol aumentan (p<0.05) en los animales suplementados, mientras que los triglicéridos, la albúmina y la urea no difieren entre los grupos (p>0.05). Las heces de ovejas suplementadas no interferían en la reproducción de las colas de caballo. Conclusiones. A la dosis administrada, el (PhSe)2 no es capaz de controlar el parasitismo; sin embargo, aumenta los niveles de globulinas y colesterol, que son importantes para la respuesta inmune y para la reproducción, respectivamente. Las heces de animales suplementados pueden usarse como fertilizantes orgánicos, sin impactos negativos en ambiente.

ABSTRACT Objective. The aim of this study was to evaluate the influence of subcutaneous supplementation with diphenyl diselenide ((PhSe)2) in dairy sheep infected with gastrointestinal nematodes on animal health and possible damage to environment when the feces of these animals will be used for fertilizing. Materials and methods. The experiment was performed using 16 primipara dairy sheep, that were divided into two groups: the group A as control and the group B supplemented with 3 µmol/kg of (PhSe)2 subcutaneously. Blood samples were used to determine the hepatic function, as well as the protein and lipid metabolism in animals. Feces were used to determine the number of helminths eggs per gram of feces (EPG), as well as used for ecotoxicology tests. Results. The (PhSe)2 supplementation not affected the helminths reproduction, since the EPG did not differ (p>0.05) between groups. Total protein and globulin levels increase (p<0.05) in supplemented animals, while the seric alanine aminotransferase (ALT) levels decrease (p<0.05) in the end of experimental design. Cholesterol levels increase (p<0.05) in the supplemented animals, while triglycerides, albumin and urea not differ between groups (p>0.05). The feces of supplemented sheep not interfered the springtails reproduction. Conclusions. At the administered dose, the (PhSe)2 is not able to control the parasitism, however, it did increase the globulins and cholesterol levels, that are important to immune response and for sheep reproduction, respectively. Also, the feces of supplemented animals with (PhSe)2 can be used as organic fertilizing, without negative impacts to environment.

RESUMEN Objetivo. El objetivo de este estudio fue evaluar el efecto de la infección subclínica por agentes de la fiebre por garrapatas en el ganado lechero en producción de leche, la composición y calidad. Materiales y métodos. El estudio se realizó en una finca privada con 75 vacas lecheras alojadas-libre puesto, y de estas se evaluaron 37. Se recogieron muestras de leche individuales mensuales para determinar la composición (grasa, lactosa, proteína y sólidos totales) y la calidad (recuento de células somáticas (SCC)). Además, se recogieron muestras de sangre para identificar vacas que fueron negativas a fiebre de garrapatas y positivos por PCR para uno o más de los siguientes agentes etiológicos: Babesia bovis, Babesia bigemina y Anaplasma marginale. Resultados. Los resultados mostraron un aumento de SCC en los animales positivos, al menos para uno de los agentes cuando se comparó con vacas no infectadas (p<0.05). La producción de leche fue significativamente menor en A. marginale animales positivos (p<0.05). Un aumento de aproximadamente el 40% en el contenido de sólidos de la leche fue encontrado en vacas positivas a B. bovis. También, un incremento de aproximadamente el 23% de la lactosa se encontró en vacas positivas para B. bigemina. Conclusiones. Se puede concluir que la presencia de al menos uno de estos parásitos en el ganado lechero afecta composición o calidad de su leche.

ABSTRACT Objective. The objective of this study was to evaluate the effect of subclinical infection by agents of tick fever in dairy cattle on milk parameters, such as production, composition, and quality. Materials and methods. The study was conducted in a private farm with 75 free-stall-housed dairy cows, from which 37 were evaluated. Monthly, individual milk samples were collected for compositional (fat, lactose, protein, and total solids) and quality (somatic cell counts (SCC)) analyses. In addition, blood samples were collected in order to identify cows that were tick fever-negative and positive by PCR for one or more of the following etiological agents: Babesia bovis, Babesia bigemina and Anaplasma marginale. Results. The results showed increased SCC in positive animals for at least one of the agents when compared to non-infected cows (p<0.05). Milk production was significantly lower in A. marginale positive animals (p<0.05). An increase of about 40% in milk solids content was found in B. bovis positive cows. Also, an increment of approximately 23% in lactose was found on cows positives for B. bigemina. Conclusions. We may conclude that the presence of at least one of these parasites in dairy cattle affects composition or quality of their milk.