To evaluate the risks of hair dye exposure, we investigated cellular and molecular effects of Arianor Ebony dye, which is a mixture of azo and anthraquinone dyes, used in the composition of the black color. Cytotoxicity, genotoxicity, and gene expression of relevant molecules of apoptotic and oxidative stress mechanisms were investigated in HepG2 cells exposed to Arianor Ebony. Results showed that the dye did not induce cytotoxicity to exposed cells at a concentration up to 50 µg/mL compared to the negative control. However, genotoxic assays indicated that the dye was able to damage the genetic material at a concentration of 25 µg/mL, with induction factor values of exposed cells two- to five-fold higher than those recorded for the negative control. Moreover, the lowest observed effect concentration was 12.5 µg/mL. For gene expression, relevant changes were observed in cytochrome c and caspase 9, which decreased in cells incubated with the dye in a dose-dependent manner when compared with the negative control. In parallel, the expression of genes for antioxidant enzymes was increased in exposed cells, suggesting the presence of metabolic routes that protect cells against the toxic effect of the dye, avoiding exacerbated cellular death. Results suggested that the dye disrupted cellular homeostasis through mitochondrial dysfunction, which may be hazardous to human health. Thus, further investigations are necessary to deeply understand the mechanisms of action of the dye, considering its toxic potential found in our ex vivo assays.

Avaliaram-se o consumo e a digestibilidade aparente de dietas, contendo diferentes proporções de silagem de girassol em substituição à silagem de milho, para vacas leiteiras em lactação. Foram utilizadas cinco vacas da raça Holandesa, que produziam 25kg leite/dia, distribuídas em um delineamento em quadrado latino 5<FONT FACE=Symbol>´</FONT>5. Os tratamentos foram compostos por: 100% de silagem de girassol e concentrado (100SG), 66% de silagem de girassol mais 34% de silagem de milho e concentrado (66SG), 34% de silagem de girassol mais 66% de silagem de milho e concentrado (34SG), 100% de silagem de milho e concentrado (100SM) e 100% de silagem de milho mais caroço de algodão (16,5% da matéria seca) e concentrado (SM+CA). A ingestão de matéria seca (17,8kg para 100SG e 21,6kg para 100SM), a ingestão de matéria orgânica (15,5kg para 100SG e 20,2kg para 100SM), a ingestão de fibra insolúvel em detergente neutro (8,1kg para 100SG e 9,9kg para 100SM), a digestibilidade aparente da fibra insolúvel em detergente neutro (30,7% para 100SG e 51,4% para 100SM) e da fibra insolúvel em detergente ácido (28,4% para 100SG e 49,4% para 100SM) foram menores para a dieta 100SG comparada à dieta 100SM (P<0,05). A substituição parcial da silagem de milho pela silagem de girassol pode ser uma alternativa viável na alimentação de vacas leiteiras.

The intake and the apparent digestibility of dry matter, organic matter, neutral detergent fiber, acid detergent fiber and the intake of crude protein were evaluated in lactating Holstein cows fed sunflower silage (SS) in replacement of corn silage (CS) in their diets. Five ruminal cannulated cows, 60 to 82 days in milk, were arranged in a 5 x 5 latin square design. The treatments werethe following: 100% corn silage (100CS) and concentrate; 34% sunflower silage plus 66% corn silage (34SS) and concentrate; 66% sunflower silage plus 34% corn silage (66SS) and concentrate; 100% sunflower silage (100SS) and concentrate;and 100% corn silage plus whole cotton seed (CS-WCS) and concentrate. Dry matter (17.86kg for 100SS and 21.62kg for 100CS) and organic matter intake (17.5kg for 100SS and 20.2kg for 100CS), intake and apparent digestibility of neutral detergent fiber and acid detergent fiber were lower for 100SS compared to 100CS (P<0.05). Apparent digestibility of organic matter for treatment 100SS was the lowest (54.8%). Increasing levels of corn silage in the diets increased the dry matter intake, the organic matter intake and the apparent digestibility. Parcial replacement of the corn silage with sunflower silage could be a viable option for lactating cows diets.

Avaliaram-se a produção e a composição do leite de vacas alimentadas com dietas contendo diferentes proporções de silagem de girassol, em substituição à silagem de milho na dieta, e caroço de algodão como substituto parcial do concentrado. Foram utilizadas cinco vacas holandesas com 25kg leite/dia, distribuídas em um delineamento em quadrado latino 5×5. Os períodos foram de 21 dias e os tratamentos foram as dietas compostas por: 100% de silagem de girassol e concentrado (100SG), 66% de silagem de girassol e 34% de silagem de milho e concentrado (66SG), 34% de silagem de girassol mais 66% de silagem de milho e concentrado (34SG), 100% de silagem de milho e concentrado (100SM) e 100% de silagem de milho mais caroço de algodão (16,5% da matéria seca) e concentrado (16,5CA). As produções de leite, proteína e extrato seco total foram inferiores no tratamento 100SG em relação ao 100SM (P<0,05). A substituição parcial de silagem de milho por silagem de girassol não afetou as produções de leite, gordura ou proteína. A substituição parcial de concentrados por caroço de algodão não afetou as características estudadas.

Milk production and composition of Holstein cows fed diets in which sunflower silage replaced corn silage as the forage component were studied. Five Holstein cows with 25kg milk/day, 60 to 82 DIM, were arranged in a 5×5 Latin Square design. Periods were 21 days and treatments were: 100% sunflower silage plus concentrate (100SG); 66% sunflower silage, 34% corn silage plus concentrate (66SG); 34% sunflower silage, 66% corn silage plus concentrate (34SG); 100% corn silage plus concentrate (100SM); or 100% corn silage plus whole cottonseed (16.5% of dry matter) and concentrate (16.5CA). Milk yield, milk protein yield, and total milk solids yield were lower for 100SG compared to 100SM (P<0.05). Partial replacement of corn silage with sunflower silage did not affect milk, fat and protein yield. Partial replacement of concentrates with whole cottonseed did not affect any of the studied variables.