In the hilly areas of Central Italy, where the different farms are located, the use of hay and silage of forage crop, such as lucerne, is frequent. Although they represent an interesting nitrogen source for the high rumen degradability, they nevertheless require the addition of highly fermentable carbohydrate concentrates. For this purpose barley and maize, mostly produced on the farm, are the best source of energy. To verify the effect of these carbohydrate sources on the metabolic state and the productive performance of lactating Comisana ewes, an investigation was carried out on 10 secondiparous animals of single birth (2 groups of 5 each). They were fed two isoenergetic diets including both (on the DM) 61% 2nd cut lucerne hay, 3% lucerne silage, 4% f laked soybean and differing for the remaining 32%, represented respectively by flaked barley (FB diet) and ground ear maize (GEC diet). The apparent digestibility of the several nutritional parameters was determined, using the indirect method of the acid insoluble ash, according to a Latin square 2x2 experimental design, with 25-day periods including adaptation (15 d) and the experimental phase (10 d). On each animal the following parameters were determined: daily intake of dry matter and milk yield; metabolic profile; physico-chemical, technological and cellular characteristics of the milk at the 1st, 4th and 10th day of the trial. The animals fed the FB diet had a better digestive utilisation of all the nutritional parameters and, consequently, a better intake of DM (101.18 vs 93.17 g/ kg0.75). Regarding the metabolic-nutritional aspect, the two rations had no digestive repercussions, in fact the haematic levels of several of the parameters were in the range for normal metabolism, except those higher in urea in the animals fed the FB diet. The ewes of group FB produced more milk than those of the GEC group; this was annulled by normalizing this parameter to 6.5 % fat. The different concentrations of NDF and NSC of the two diets could have caused the differences in the milk fat content of the two experimental diets (6.55 vs 7.26 %).
Effect of two non-structural carbohydrate sources on the metabolism and productive performance of lactating Comisana ewes
DE VINCENZI, Sergio;PAUSELLI, Mariano;CASOLI, Carmen;COSTANTINI, Francesco;DURANTI, Emilia;
1999
Abstract
In the hilly areas of Central Italy, where the different farms are located, the use of hay and silage of forage crop, such as lucerne, is frequent. Although they represent an interesting nitrogen source for the high rumen degradability, they nevertheless require the addition of highly fermentable carbohydrate concentrates. For this purpose barley and maize, mostly produced on the farm, are the best source of energy. To verify the effect of these carbohydrate sources on the metabolic state and the productive performance of lactating Comisana ewes, an investigation was carried out on 10 secondiparous animals of single birth (2 groups of 5 each). They were fed two isoenergetic diets including both (on the DM) 61% 2nd cut lucerne hay, 3% lucerne silage, 4% f laked soybean and differing for the remaining 32%, represented respectively by flaked barley (FB diet) and ground ear maize (GEC diet). The apparent digestibility of the several nutritional parameters was determined, using the indirect method of the acid insoluble ash, according to a Latin square 2x2 experimental design, with 25-day periods including adaptation (15 d) and the experimental phase (10 d). On each animal the following parameters were determined: daily intake of dry matter and milk yield; metabolic profile; physico-chemical, technological and cellular characteristics of the milk at the 1st, 4th and 10th day of the trial. The animals fed the FB diet had a better digestive utilisation of all the nutritional parameters and, consequently, a better intake of DM (101.18 vs 93.17 g/ kg0.75). Regarding the metabolic-nutritional aspect, the two rations had no digestive repercussions, in fact the haematic levels of several of the parameters were in the range for normal metabolism, except those higher in urea in the animals fed the FB diet. The ewes of group FB produced more milk than those of the GEC group; this was annulled by normalizing this parameter to 6.5 % fat. The different concentrations of NDF and NSC of the two diets could have caused the differences in the milk fat content of the two experimental diets (6.55 vs 7.26 %).I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
