RESUMO
Estudaram-se o efeito do transporte e a mudança de local de manejo sobre a produção e a composição do leite e sobre as variáveis fisiológicas, utilizando-se 12 cabras da raça Alpina em final de lactação. Semanalmente, foram mensuradas a produção e composição do leite e a contagem de células somáticas, além do volume do leite residual após administração de ocitocina. Foram colhidas amostras de sangue para dosagem hormonal (cortisol) e enzimática (glicose) no plasma no dia do transporte: antes (7h10min) e após (8h20min, 8h30min e 10h30min) o transporte. Nas três semanas subsequentes ao transporte, também foram colhidas amostras de sangue às 8h20min. Obtiveram-se teores mais elevados (P<0,05) de cortisol e glicose após o transporte e a mudança de local de manejo, e menor produção de leite (P<0,05) um dia após o evento. Porcentagem de gordura (P<0,05) e contagem de células somáticas apresentaram diferenças significativas (P<0,05) após o transporte. Os resultados permitem concluir que o transporte é um agente estressor que pode, momentaneamente, influenciar a produção animal.
The effects of transportation and reallocation on milk production and composition and physiological responses were studied in 12 late-lactation Alpine goats. Weekly, somatic cell count, milk production and composition, and residual milk volume (after administration of oxytocin) were monitored. Blood samples were taken for hormonal (cortisol) and enzymatic dosages (glucose) in plasma on the day of transportation: before (7h10min) and after transportation (8h20min, 8h30min, and 10h30min). During the three weeks after transportation, blood samples were also taken at 8h20min. Higher levels (P<0.05) of cortisol and glucose after transportation and reallocation were observed and milk yield was significantly lower (P<0.05) one day after them. Milk fat percentage and somatic cell count (P<0.05) were higher after transportation. Results allow concluding that transportation is a stressor agent that may momentarily influence animal production.
RESUMO
The coordination compounds [Cu(bpy-MV2+)(PPh3)2](PF6)3, where bpy-MV2+ is the 1-(4-(4'-methyl-2,2'-bipyridin-4-yl)butyl)-1'-methyl-4, 4'-bipyridinediium(2+) cation, and [Cu(dmb)(PPh3)2](PF6), where dmb is 4,4'-dimethyl-2,2'-bipyridine, have been prepared and characterized. Visible light (417 nm) excitation of [Cu(bpy-MV2+)(PPh3)2]3+ at room temperature leads to rapid intramolecular electron transfer, kcs > 1 x 10(8) s-1, to form a charge-separated state with an electron localized on the pendant viologen group and a copper(II) metal center, abbreviated [CuII-bpy-MV.+]. This state recombines to ground-state products with first-order rate constants that can be tuned with solvent over a approximately 10(7)-10(5) s-1 range. The activation parameters were determined from temperature-dependent electron-transfer data with Arrhenius analysis. A model is proposed wherein a solvent molecule is coordinated to Cu(II) in the charge-separated state, [(S)CuII-bpy-MV.+]. Visible light excitation of [Cu(dmb)(PPh3)2](PF6) in argon-saturated dichloromethane produces long-lived photoluminescent excited states, tau = 80 ns, that are dynamically quenched by the addition of Lewis basic solvents. The measured quenching constants each correlate well with the lifetime of the charge-separated state measured after excitation of [Cu(bpy-MV2+)(PPh3)2]3+ in the corresponding solvent.
