Sheep fed with rations that include tagasaste (Chamaecytisus proliferus subsp. palmensis)to replace alfalfa. II. Digestibility and nutrient consumption

The objective of the experiment was to evaluate digestibility in vivo and nutrient consumption of rations for sheep that include increasing quantities of tagasaste (Chamaecytisus proliferus subsp. palmensis) to replace alfalfa (Medicago sativa L.). Twenty-four young Suffolk Down rams with a initial live weight of 38 kg were fed with alfalfa pellets and increasing levels of tagasaste soiling. The diets were: 100% alfalfa (T0); 70% alfalfa and 30% tagasaste (T30); 40% alfalfa and 60% tagasaste (T60); and 10% alfalfa and 90% tagasaste (T10). The total intake of digestible dry matter and digestible organic matter were of 1.191; 1.102; 855 and 687 and of 1.108; 1.046; 820 and 670 g animal-1 d-1 for the four treatments, respectively. The coefficients of digestibility (D) of dry matter (59.4 to 61.3%), organic matter (60.9 to 62.3%), and total protein (PT) (72.4 to 73.3%) were similar (P > 0.05) on increasing the proportion of tagasaste; on the other hand, the digestibility (D) of acid detergent fiber (ADF) had a tendency to diminish (P ≤ 0.05). The increase from 0 to 90% of tagasaste in the ration produced a decrease (P ≤ 0.05) of PT, ADF and metabolizable energy (ME) intake. The PT intake, in all treatments (188.4 to 368.3 g animal -1 d-1), supplied fattening nutrient requirements. The ME intake in T60 and T90 (3.43 and 2.69 Mcal animal-1 d-1, respectively) was not sufficient to supply nutrient requirements for a quick fattening. El experimento tuvo como objetivo evaluar la digestibilidad in vivo y el consumo de nutrientes en raciones para ovinos, que incluyen cantidades crecientes de tagasaste (Chamaecytisus proliferus subsp. palmensis) en reemplazo de heno de alfalfa (Medicago sativa L.). Se utilizaron 24 carnerillos Suffolk Down, con un peso vivo promedio inicial de 38 kg, los que fueron alimentados con pellet de alfalfa y niveles crecientes de soiling de tagasaste. Las raciones fueron: 100% alfalfa (T0); 70% alfalfa y 30% tagasaste (T30); 40% alfalfa y 60% tagasaste (T60); y 10% alfalfa y 90% tagasaste (T90). El consumo total de materia seca digestible y materia orgánica digestible fue de 1,191; 1,102; 855; y 687 y de 1,108; 1,046; 820; y 670 g animal-1 d-1 para los cuatro tratamientos, respectivamente (P ≤ 0,05). Los coeficientes de digestibilidad (D) de la materia seca (59,4 a 61,3%), materia orgánica (60,9 a 62,3%), y proteína total (PT ) (72,4 a 73,3%) fueron similares (P > 0,05) al aumentar la proporción de tagasaste; en cambio, la digestabilidad (D) d