Effect of Seasonal Stress on Growth Performance, Blood Hemato-biochemical, Antioxidant, Thyroid Hormones and HSP 70 Gene Expression Profile of Beetal Does and Goat Kids

A study was conducted on adult beetal does and growing kids to analyze the effect of seasonal change on various physiological and molecular parameters. Blood samples was collected on 0, 15, 30, and 45th day during summer and winter season. The Average THI was found higher (83.08±0.35) during the summer season, while relative humidity remained high (63.77±2.32) during the winter season. As per ANOVA, values of rectal temperature, respiration rate, heart rate, packed cell volume, hemoglobin, total erythrocyte, and leukocyte count, lymphocyte, eosinophil, total bilirubin, creatinine, blood urea nitrogen, serum ALT, AST, ALP enzyme levels, erythrocytic lipid peroxidation, reduced glutathione, total antioxidant capacity (FRAP value) were found significantly higher, while the values of average daily gain, neutrophil %, glucose, total protein, albumin, globulin, total cholesterol, triglyceride, erythrocytic superoxide dismutase levels were found significantly lower during summer season compared to the winter season. Levels of all tested antioxidants parameters were found significantly lower in goat kids compared to adult does. HSP 70 gene expression levels were found significantly higher, while mitochondrial Cyt-B and COX-I gene expression levels were found significantly lower during the summer season relative to winter season in beetal goats. Overall effect of the summer season on HSP 70, CYTB, and COX-I gene expression relative to winter season was found higher in goat kids compared to adult does. Thus goat kids were found to be more susceptible to heat stress than an adult does. Overall study indicated that adaptability of goats to seasonal stress is governed by altered physiological state of goats in different seasons

Atividade antioxidante de macrófagos alveolares em ratos endotoxêmicos

Avaliou-se o efeito da endotoxemia sobre a atividade antioxidante de macrófagos alveolares em ratos da linhagem Wistar. Foram utilizados 24 ratos machos, com idade entre 90 e 120 dias, os quais foram divididos em dois grupos: controle e endotoxêmico. O grupo endotoxêmico foi submetido à injeção intraperitonial de lipopolissacarídio na dose de 1mg/kg de peso corporal. Após 24 h, coletou-se sangue para contagem total e diferencial de leucócitos; lavado broncoalveolar para contagem total e diferencial dos leucócitos e, a partir de macrófagos isolados deste lavado, foram realizadas as dosagens de superóxido e superóxido dismutase. A endotoxemia aumentou a contagem total de leucócitos e o número de neutrófilos no sangue periférico, no lavado broncoalveolar, e aumentou a produção de superóxido sem modificar a produção da superóxido dismutase. Esses resultados sugerem que a endotoxemia induz a uma resposta inflamatória no pulmão. Contudo, não altera a atividade antioxidante em ratos adultos. Tal fato potencializa a resposta contra agentes infecciosos pelo hospedeiro, mas também pode contribuir na patogênese de injúria pulmonar.The effects of endotoxemia on the antioxidant activity in alveolar macrophages of Wistar rats were evaluated. Twenty-four male rats, 90-120 days of age, were separated into 2 groups: control and endotoxemic. To the endotoxemic animals was administered, intraperitoneally, a lipopolyssaccaride at dosage of 1mg/kg body weight. Twenty-four hours after this procedure, blood was collected for total and differential leukocytes counts. In addition, bronchoalveolar lavage was collected for total and differential leukocyte counting. From this lavage macrophages were isolated for the dosage of superoxide and superoxide dismutase. The endotoxemia increased the total leukocyte counts and the number of neutrophils in the peripheral blood and bronchoalveolar lavage of the rats. There was an increased superoxide production without changing the superoxide dismutase. Our findings indicate that endotoxemia induces lung inflammatory response. However, it does not alter the antioxidant activity in adult rats. This fact not only enhances host response against infectious agents, but might also contribute to the pathogenesis of pulmonary injury

Cretaceous extinctions: multiple causes

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