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Feedlot cattle is submitted to a diet rich in energy and reduced in fibres that induces the sub-acute ruminal acidosis (SARA) with its lesions and clinical signs. Recent studies have demonstrated some amelioration of this condition by the use of isoquinolone alkaloids found in Macleaya cordata (Papaveraceae) such as Sanguinarine and Chelerythrine. These compounds have demonstrated antimicrobial, anti-in?ammatory and immune-modulatory effects in both humans and animals The aim on this study, using histopathology and a score system, was to evaluate the differences between a non-treated and a treated group feed with these alkaloids, present in trade preparation Sangrovit-RS® as a source of sanguinarine (SG), chelerythrine (CH) and protropine (PA) standardized to 0.15% w/w SG, using feedlot cattle under a high-grain diet as an inflammatory model for gastrointestinal system. The samples of forestomachs were evaluated and graded using scores ranging from zero (0) to three (3) obtained at light-microscopic fields of 400X. Parameters such as inflammation, hydropic degeneration, hyperkeratosis, and vesicle formation were accessed in the different layers of the tissues, considering the severity and dispersion of the microscopic lesions. The soft tissues such as the abomasum, small intestine, cecum and colon had their total amount of inflammatory cells counted at light-microscopic fields of 200X. The rumen of the SG-CH-PRO-treated group showed a significant reduction in the epithelial hydropic degeneration scores (p ? 0.001) and lamina propria inflammation (p ? 0.001).The reticulum had a similar reduction in scores of epithelial (p ? 0.002) and stratum corneum hydropic degeneration (p ? 0.001), hyperkeratosis (p ? 0.002) and inflammation in lamina propria (p ? 0.001) and epithelium (p ? 0.002). The omasum had no significant differences. All non-keratinized tissues, except for ileum, had a significant decrease (p ? 0.001) in the total counting of inflammatory cells. In this trial, the feedlot cattle feed with high grain diet and treated with isoquinolone alkaloids expressed lesions that indicate ameliorations and worsening’s. Ameliorating effects of the alkaloids were better demonstrated in tissues with reduced or no corneal layer in the mucosa and in the absence of a lipopolysaccharides rich acidic environment reinforcing the notion of the topic action, the dependence of the media pH and the time of exposure modulating the pharmacological mechanisms of these alkaloids. The observed cytolytic (oncolysis) effect in epithelial forestomachs cells under low pH values, worsening the osmotic status, should be considered before clinical applications.

A resposta imune tardia direcionada para eliminação da hemoncose pode ser modulada pelo perfil Th2, sendo os eosinófilos as principais células efetoras responsáveis pela eficiente eliminação do parasita; ou modulada pelo perfil Th1, sendo os neutrófilos as principais células efetoras, que promovem eliminação parasitária mais deficiente, pois testes in vitro demonstraram que o parasita deprime o metabolismo oxidativo dos fagócitos. Desta maneira, este trabalho objetivou avaliar se o grau de infecção parasitária observado pela quantidade de ovos por grama de fezes (OPG) de Haemonchus contortus interfere no leucograma e se impacta no metabolismo oxidativo leucocitário em ovino naturalmente acometido por hemoncose. Para tanto, 39 ovinos machos adultos e sem alterações no exame físico, excetuando-se a coloração das mucosas, foram separados em 4 grupos conforme a infecção parasitária 0-350 (n=15), 400 a 1000 (n=10), 1100-2000 (n=7) e 2100-4700 (n=7). Notou-se correlação significativa positiva entre OPG e neutrófilos (r=0,56; P=0,0003) e significativa negativa entre OPG e eosinófilos (r=-0,50; P=0,0012) e OPG e metabolismo oxidativo leucocitário (P=0,0001), permitindo concluir que há relação entre as células efetoras e a severidade de infecção parasitária em ovinos naturalmente infectados por hemoncose. Também se verificou que a alta infecção parasitária promove diminuição do metabolismo oxidativo de leucócitos. Palavras-chave: Helmintos; metabolismo oxidativo; neutrófilos; eosinófilos.

Evaluation of alveolar macrophage functions of cattle is an important tool in order to assess whether measures taken during the cattle husbandry can decrease the respiratory tract defense. The aim of this study was to determine whether dexamethasone used at therapeutic dose can affect the oxidative metabolism of alveolar macrophages of cattle. This was evaluated by two tests, the fluorometric and colorimetric. The similarity of the results was studied, using alveolar macrophages of six healthy cattle, obtained from bronchoalveolar lavage on a basal and an immunosuppressant moment after the application of dexamethasone. For the fluorometric test, alveolar macrophages were incubated with Staphylococcus aureus and 2’-7’dichlorohidroflurescein, and analyzed by flow cytometer. For the colorimetric test, alveolar macrophages were incubated with Phorbol 12- miristate-13 acetate and nitroblue tetrazolium, dissolved and analyzed in a spectrophotometer. It was noted that dexamethasone therapeutic dose (0.05 mg/kg) reduced the functions of alveolar macrophages from healthy bovine. This result was observed by both tests with the difference that the flow cytometry assay was more informative for identifying which specific cellular function has been compromised.