Manuel Sanz

THE METABOLIC USE OF ENERGY FROM DIETARY FAT IN BROILERS IS AFFECTED BY FATTY ACID SATURATION

1. Two experiments were performed to evaluate the effect of dietary fat on performance and fat and protein accretion in broiler chickens according to the degree of saturation. 2. The first experiment was designed to test 2 sources of dietary fat and 3 levels of dietary energy using a factorial (2 × 3) experimental design. The foods were formulated to maintain a constant ratio of energy to protein (and other nutrients). There were no significant differences in weight gain, intake, final body weight or food to gain ratio between broilers fed on diets differing solely in the degree of fat saturation. Broilers fed on diets containing animal fat showed higher whole-body fat retention (P = 0.02) and lower protein accretion (P = 0.03) than those fed on diets containing vegetable oils. 3. In the second experiment, only 1 concentration of fat (tallow, lard or sunflower oil) was incorporated into the experimental diets, providing different energy to protein ratios. The carcase protein content was not affected by dietary fat source, while total fat accretion (P = 0.01) and energy retention (P = 0.14) were highest in broilers fed on a diet containing tallow. 4. The findings suggest that the degree of saturation of dietary fats affects their metabolic use and fat accumulation in broiler chickens.

Lower lipid oxidation in the muscle of rabbits fed diets containing oats

The susceptibility to oxidation of rabbit longissimus dorsi samples from animals receiving 300 g kg−1 oat in the feed was compared to samples from control animals receiving a diet based on barley. Dietary oat in rabbit diets balanced in digestible energy and protein did not affect feed efficiency, carcass weight and fatness. Also, intramuscular fat content was not affected by dietary treatment. Fat unsaturation, as assessed by the unsaturation index, was not modified by dietary treatment for neutral and polar lipids. After 8 days of storage thiobarbituric acid reactive substances (TBARS) of muscle samples from rabbits fed the control diet and rabbits fed the diet containing 300 g kg−1 oats were 1.32 and 0.67 mg malonaldehyde kg−1 muscle (P < 0.001), respectively. Dietary oats also reduced drip loss in longissimus dorsi muscle (P < 0.05). The presence of oat antioxidants and their possible synergistic effects suggest an interesting way of improving meat stability during storage.

Effect of dietary lard on performance, fatty acid composition and susceptibility to lipid peroxidation in growing-finishing female and entire male pigs

The effect of increasing the energy concentration of growing-finishing pig diets through inclusion of lard on performance, carcass and meat composition and lipid susceptibility to peroxidation was studied. A total of 720 Landrace × Large White male and female pigs (equal number of entire males and females) were used. Experimental diets were formulated to have a low (3000 kcal ME kg−1) or high (3200 kcal ME kg−1) energy level, but in all cases to have a constant lysine:ME ratio. This was achieved using a low (6.8 g kg−1) and a high (49.3 g kg−1) level of dietary lard inclusion. Gilts had lower daily gain (P < 0.0001) and worse feed conversion efficiency (P < 0.0001) than entire males. Susceptibility to oxidation was not affected by sex. Fat concentration in pig diets equilibrated in metabolizable energy and protein did not modify average gain, but reduced feed intake (P < 0.02), improved the gain:feed ratio (P < 0.0001), increased dressing percentage (P < 0.02) and produced higher carcass weight (P < 0.01)...

Hemorragia digestiva alta como forma de presentación de carcinoma renal metastásico

Resumen Una de las caracteristicas del hipernefroma es su gran potencial metastasico, con el consiguiente desarrollo de metastasis en el pulmon, cerebro, hueso y, con menor frecuencia, en piel, pancreas, esofago y estomago, entre otras localizaciones. La aparicion de estas metastasis suele ser tardia y, en caso de localizarse en el estomago, como el paciente que presentamos, la hemorragia digestiva alta puede ser el primer signo de alerta.