Brewey waste as a substitute for soy protein in soy-brewer's yeast mixtures to feed broiler chickens / Uso del desecho de cervecería (jugo de nepe) en la sustitución de la proteína de soya en dietas para aves

We examined the replacement of soy isolated protein by a solid fraction coming from brewery liquid wastem in the preparation of soy protein and brewer's yeast mixtures (50:50) to feed growing chickens. The replacement of 20 percent soy protein by brewery waste protein to the diet, showed no significant differences in the groeth and intake of the chickens, when compared with soy protein fed chickens. Protein efficiency Ratio (PER) and Net Protein Ratio (NPR) values of the diets were also very similar and the concentration of plasma and liver lipids remained approcimately the same. Higher levels of brewery waste reduced the performance of chickens athough total lipids, cholesterol and triacylglycerols in plasma, as well as total lipids and cholesterol in liver were not affected. The data reported here indicated that brewery waste can be used as a complementary protein source in broiler chicken diets

Effect of the type of dietary fat on cholesterolemia in rabbits fed brewer's yeast / Efecto de la grasa dietaria sobre el colesterol del plasma en conejos alimentados con levadura de cerveza

To determine the effects of the kind of dietary fat on cholesterolemia in rabbits fed with brewer's yeast, diets based on soybean protein isolate or on a mixture of soybean protein isolate and brewer's yeast (1:1) were used. They were combined with corn oil and coconut oil in four balanced, cholesterol-free diets. Twenty four rabbits were fed with 79 grams of diet per day during 3 weeks. After 14 hours of fasting on the 22nd day, blood samples from the marginal aer vein were collected, animals were sacrified and their livers dissected. there were no significant differences in the final plasma concentrations of the total lipids, tryglycerides, total cholesterol, high density lipoprotein-cholesterol, and (low density lipoprotein + very low density lipoprotein)-cholesterol, even though groups fed yeast presented the highest values. Liver lipids were not affected by dietary treatment. However, when comparing the final plasma cholesterol with initial cholesterol, a significant increase in the groups which consumed yeast with corn oil (48 mg/dL) and coconut consumed soybean protein with corn oil (21 mg/dL) and coconut oil (36 mg/dL). The two-way variance analysis of these data showed that there was no fat- protein interaction and the hypercholesterolemic effects observed were associated with brewer's yeast consumption

Effect of addition of brewer's yearst to soy protein and casein on plasma cholesterol levels of rabbints / Niveles de colesterol plasmático en conejos alimentados con dietas de soya y caseina enriquecidas con levadura de cerveza

The purpose of this study was to determine whether the addition of high levels of years to casein and soy diets could modify the well known effects of any of these proteins on plasma cholesterol. Rabbits, were fed either a diet containing soybean protein-brewer's yeast or casein-brewer's yeast (each protein source providing 50 per cent of the dietary nitrogen content) and casein and soybean protein basal diets. Brewer's yeast was obtained from a local beer factory in its non-debitered form. The diets contained 20 per cent protein, 9 per cent coconut oil and 1 per cent corn oil, with no added cholesterol. After a 22 day experimental period, rabbits fed casein developed hypercholesterolemia whereas those fed the soy bean protein diet did not. The replacement of 50 per cent of hte soy nitrogen by brewer's yeast nitrogen, increased the total cholesterol plasma level, but significant differences were only observed between rabbits fed casein and casein-yeast and those fed soybean protein. No differences in high density lipoprotein cholesterol could be detected among the groups. However, the HDL-cholesterol/total cholesterol ratio was significantly reduced in responce to soy substitution by brewer's yeast. The (low density lipoprotein + very low density lipoprotein)-cholesterol was increased in all groups whith the exception of the animals fed purely soy protein. these data suggest a hypercholesterolemic activity of the dietary non-debittered brewer's yeast. Nevertheless, according to the amino acid composition, the factor responsible for the reported effects of dietary yeast was not associated with a high lysine to arginine ratio which could be due to extracellular components

Efecto de la concentración dietaria de la levadura (Saccharomyces carlsbergensis) recuperada de la cerveza, en pollos macho Warren / Effect of dietary concentration of Saccharomyces carlsbergensis yeast recovered from beer, in Warren male chicks

Con el objetivo de establecer el nivel máximo de sustitución del aislado proteínico de soya por la proteína de la levadura Saccharomyces carlsbergensis, recuperada de la cerveza, con los menores efectos metabólicos relacionados, se alimentarón por 15 días un total de 42 pollos macho (Warren), de 1 día de edad, divididos en seis grupos con siete animales cada uno. Cada grupo recibió una de las dietas con 0%, 25%, 50%, 75% y 100% del suplemento proteínico basado en proteína de levadura, adicionada a expensas del aislado proteínico de soya. A fin de estimar el valor NPR de la proteína de la levadura, se incluyó también un grupo, el cual recibió una dieta libre de proteínas. Se determinaron la utilización proteínica y los cambios de lípidos totales, triglicéridos y colesterol, tanto en el plasma como en el hígado. En los grupos alimentados con 75% y 100% de proteína de levadura, se observó un descenso en el crecimiento y un incremento en las concentraciones hepáticas y renales del ácido úrico, si bien el consumo de la dieta no se modificó sustancialmente. Así, la utilización de proteína medida como PER y NPR, fue menor en estos grupos. El ácido úrico plasmático no se modificó en ninguno de los grupos. Los lípidos plasmáticos tampoco se modificaron a ninguna concentración de levadura, mientras que en el hígado, los lípidos totales disminuyeron, así como los triglicéridos, al incrementarse la levadura dietaria. Los resultados indicaron que le nivel máximo de sustitución de la proteína de levadura usando células completas en dietas iniciadoras para pollos, es del 50%