Abstract: The aim of this study was to evaluate whether the use phytogenic as feed additive of Holstein calves could exert beneficial effects on animal health and performance. Thirty newborn calves were randomly divided into two groups (control and treated), and the treated consisted of 10 g of the phytogenic product diluted in milk once a day for 30 days. Blood and fecal samples were collected, and fecal score was performed daily in order to determine the occurrence of diarrhea. Treated calves showed higher hematocrit on days 45 and 60 of life. Serum levels of urea, total proteins, globulins and glucose were lower in the treated group on day 60 of life, while triglycerides were lower on days 15 and 60 of life. Serum glutathione S-transferase activity was higher in treated animals on day 60 of life. Fecal bacterial count was lower in treated animals on days 30 and 60 of life. The weight gain was higher in treated animals on days 60 and 210 of life. Based on these results, it is possible to conclude that the addition of phytogenic as feed additive for calves was able to minimize fecal bacterial infections and to increase body weight gain.

Abstract Abstract: This study evaluated the effect of oregano essential oil added to the feed of commercial laying hens. This research was focused on the analysis of biochemical changes linked to hepatic function, and protein and lipid metabolism. It was used 240 laying hens (59 weeks-old) distributed in a completely randomized design of six treatments (five repetitions with eight birds each). The experiments were constituted by a control treatment (CT) with the inclusion of zinc bacitracin and five treatments of oregano essential oil (OEO: 0, 50, 100, 150, and 200 mg.kg-1), respectively. After 28 days of feeding, an increase on serum levels of total proteins and globulins was observed on groups T150 and T200, as well as an increase on albumin levels on group CT. After 84 days of feeding, a significant reduction on total proteins and albumin was observed on group T200, as well as an increase in serum triglycerides. OEO at 200 mg.kg-1 increased globulin levels on day 28, which may be considered an effect in the inflammatory response, which increases serum immunoglobulins and proteins.

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.

ABSTRACT: This study aimed to evaluate the effect of probiotics on performance, intestinal morphology and carcass characteristics of broiler chickens housed on lower or higher environmental challenge. Three hundred male Cobb chicks were distributed into four groups in completely randomised design with treatments arranged in a 2 x 2 factorial scheme to evaluate effects of two diets (with or without probiotics) and two environmental conditions (lower or higher challenge), totaling four treatments with five replications with 15 birds per box. Probiotics were added on diets and were composed of Lactobacillus acidophilus, Bacillus subtilis, Bifidobacterium bifidum and Enterococcus faecium. The environment with lower challenge was made up of new wood shavings used as litter, low bird density (8 birds/m2) and daily-cleaned bell drinkers. The environment with higher challenge was made up of re-used wood shavings used as litter (after three broods of broilers), bird density of 16 birds/m2 with bell drinkers cleaned every two days. No significant interaction between diet and environmental challenge was found for any of the variables evaluated. Performance, slaughterhouse variables and chemical carcass composition were not affected by the use of probiotics. Chicks receiving diets without probiotics had lower intestinal crypt depth (267.1 vs. 316.6 pm, P=0.0068). Birds raised in the environment with higher challenge decreased feed intake (4,660 vs 5,020 g, P=0.0422), weight gain (2,610 vs 2,810 g, P= 0.0054), drumstick and thigh yield (21.98 vs 24.14 %, P=0.0354), and increased crypt depth (325.2 vs 258.5 pm P=0.0009). In conclusion, the probiotic does not promote satisfactory improvements, regardless of the environmental challenge.

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.

A resistência de anti-helmínticos em pequenos ruminantes é um problema comum e de interesse em todo o mundo. O objetivo deste estudo foi verificar a eficácia do tratamento anti-helmíntico em ovinos naturalmente infectados. Este estudo foi realizado em nove rebanhos que utilizaram o mesmo anti-helmíntico por mais de um ano. Em cada fazenda, os animais foram divididos em dois grupos: grupo controle, não tratado (n = 5) e tratados (n = 10) com base no número de ovos por grama nas fezes (OPG). O efeito do tratamento foi avaliado com base nos resultados de OPG e coprocultura realizados antes do tratamento e 10 dias após. Não foi observada diferença significativa (P > 0,05) entre os grupos tratados e não tratados em relação aos resultados do OPG. A coprocultura demonstrou que os animais estavam infectados principalmente porHaemonchus spp., Trichostrongylus spp.,Teladorsagia spp., Cooperia spp. eOesophagostomum spp. Em todas as fazendas foi encontrada resistência anti-helmíntica dos helmintos Haemonchusspp. e Trichostrongylus spp., mas esta resistência variou muito entre fazendas. Haemonchus spp. demonstrou ser resistente ao closantel, levamisol e albendazol. Trichostrongylus spp. demonstrou ser resistente ao levamisole, closantel e albendazol. As drogas testadas mostraram-se eficientes contra Teladorsagia spp.,Cooperia spp. e Oesophagostomum spp. Com base nesses resultados, podemos concluir que a resistência anti-helmíntica às drogas testadas é um problema presente nas fazendas avaliadas.

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 byHaemonchus spp., Trichostrongylus spp.,Teladorsagia spp., Cooperia spp. andOesophagostomum 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.