Composição nutricional e avaliação de rótulo de rações secas para cães comercializadas em Jaboticabal-SP / Nutritional composition and label evaluation of dry dog foods sold in Jaboticabal-SP

Avaliaram-se 49 marcas de rações para cães adultos e filhotes comercializadas em Jaboticabal-SP. Os alimentos foram divididos em três segmentos: econômico, standard e super-premium. Nessa ordem, as rações para cães adultos apresentaram, em média, 16,9 por cento, 20,9 por cento e 27,8 por cento de proteína, 9,7 por cento, 10,5 por cento e 15 por cento de gordura, 6,4 por cento, 2,9 por cento e 1,1 por cento de fibra e 1,9 por cento, 1,9 por cento e 1,4 por cento de Ca. Para filhotes, os produtos standard e super-premium apresentaram, respectivamente, 26,1 por cento e 31,0 por cento de proteína, 10,8 por cento e 15,2 por cento de gordura, 2,6 por cento e 2,4 por cento de fibra, 2,1 por cento e 1,7 por cento de Ca e 1,6 por cento e 1,3 por cento de P. A porcentagem de rações cujos teores nutricionais declarados no rótulo não estavam de acordo com os encontrados nas análises de laboratório foi, para os produtos super-premium para filhotes, 80,0 por cento para o Ca e 60,0 por cento para a gordura; para os produtos standard para filhotes, 28,6 por cento para proteína e 57,2 por cento para o cálcio; para os produtos econômicos para cães adultos, 44,0 por cento para a fibra e 33,0 por cento para a proteína; para os produtos standard para cães adultos de 33,0 por cento para a gordura e 50,0 por cento para o Ca; e para os produtos super-premium para cães adultos, 50,0 por cento para o cálcio e 33,0 por cento para a gordura. Foram encontradas inadequações nutricionais em produtos, como teores insuficientes de proteína e altas concentrações de fibra, cálcio e fósforo.

Fortynine food products for adult or juvenile dogs, commercially available in Jaboticabal, São Paulo, Brazil, were tested for nutrient composition. The products were divided into three categories: low-cost, standard and super-premium. In that order, average compositions for adult foods were 16.9 percent, 20.9 percent and 27.8 percent protein, 9.7 percent, 10.5 percent and 15 percent fat, 6.4 percent, 2.9 percent and 1.1 percent fiber, and 1.9 percent, 1.9 percent and 1.4 percent calcium. For puppy foods, the average compositions of standard and super-premium foods were 26.1 percent and 31 percent protein, 10.8 percent and 15.2 percent fat, 2.6 percent and 2.4 percent fiber, 2.1 percent and 1.7 percent Ca, and 1.6 percent and 1.3 percent P, respectively. The percentages of products whose published label values were in disagreement with laboratory results were: super-premium products for puppies, 80 percent for Ca and 60 percent for fat; standard products for puppies, 28.6 percent for protein and 57.2 percent for Ca; low-cost products for adults, 44 percent for fiber and 33 percent for protein; standard products for adults, 33 percent for fat and 50 percent for Ca; super-premium products for adults, 50 percent for calcium and 33 percent for fat. Products with nutritional shortcomings were found, such as insufficient protein content and too high levels of fiber, calcium, and phosphorus.

Effect of policosanol on cerebral ischemia in Mongolian gerbils

Policosanol is a mixture of higher aliphatic primary alcohols isolated from sugar cane wax, whose main component is octacosanol. An inhibitory effect of policosanol on platelet aggregation and cerebral ischemia in animal models has been reported. Thus, the objective of the present study was to evaluate the effect of policosanol on cerebral ischemia induced by unilateral carotid ligation and bilateral clamping and recirculation in Mongolian gerbils. Policosanol (200 mg/kg) administered immediately after unilateral carotid ligation and at 12- or 24-h intervals for 48 h significantly inhibited mortality and clinical symptoms when compared with controls, whereas lower doses (100 mg/kg) were not effective. Control animals showed swelling (tissue vacuolization) and necrosis of neurons in all areas of the brain studied (frontal cortex, hippocampus, striatum and olfactory tubercle), showing a similar injury profile. In the group treated with 200 mg/kg policosanol swelling and necrosis were significantly reduced when compared with the control group. In another experimental model, comparison between groups showed that the brain water content of control gerbils (N = 15) was significantly higher after 15 min of clamping and 4 h of recirculation than in sham-operated animals (N = 13), whereas policosanol (200 mg/kg) (N = 19) significantly reduced the edema compared with the control group, with a cerebral water content identical to that of the sham-operated animals. cAMP levels in the brain of control-ligated Mongolian gerbils (N = 8) were significantly lower than those of sham-operated animals (N = 10). The policosanol-treated group (N = 10) showed significantly higher cAMP levels (2.68 pmol/g of tissue) than the positive control (1.91 pmol/g of tissue) and similar to those of non-ligated gerbils (2.97 pmol/g of tissue). In conclusion, our results show an anti-ischemic effect of policosanol administered after induction of cerebral ischemia, in two different experimental models in Mongolian gerbils, suggesting a possible therapeutic effect in cerebral vascular disorders

Effect of policosanol on the hepatic cholesterol biosynthesis of normocholesterolemic rats

We have suggested previously, measuring 14C-acetate incorporation into free cholesterol, that oral administration of policosanol inhibits hepatic cholesterol biosynthesis in rats. Nevertheless, since acetate has limitations to study cholesterol synthesis in vivo, we now investigate rates of incorporation of labeled water into hepatic sterol after policosanol treatment. Absolute rates of incorporation of 3H-water in sterols were depressed by policosanol by about 20 percent, giving a more accurate degree of cholesterol biosynthesis inhibition in this species. Since policosanol did not inhibit labeled mevalonate incorporation into cholesterol in rat liver, we also studied the effect of policosanol on hydroxy-methylglutaryl-coenzyme A (HMG-CoA) reductase. Reductase activity assayed in microsomes treated with policosanol remained unchanged, suggesting that cholesterol synthesis is not inhibited by a direct action of policosanol on this enzyme

Policosanol inhibits cholesterol biosynthesis and enhances low density lipoprotein processing in cultured human fibroblasts

Policosanol is a mixture of aliphatic primary alcohols isolated and purified from sugar cane wax, that induces cholesterol-lowering effects in experimental models and human beings. When human lung fibroblasts were incubated with policosanol for 48 hours prior to the experiment, a dose dependent inhibition of 14C-acetate incorporation into total cholesterol was observed, whereas labeled mevalonate incorporation was not inhibited. Even when cholesterol synthesis was not strongly inhibited, low density lipoprotein (LDL) processing was markedly enhanced. Thus, LDL binding, internalization and degradation were significantly increased after policosanol treatment. In addition, despite the fact that'cholesterol generation was not inhibited at the lowest dose of policosanol assayed, LDL processing was significantly increased. The current data indicate that policosanol inhibits cholesterol synthesis at the earliest steps of the cholesterol biosynthetic pathway. On the other hand, this study suggests that the increase in LDL processing may be partially explained by the inhibition of cholesterol biosynthesis, even though an sterol-independent mechanism might be responsible for the enhancement of LDL-receptor activity