Effects of maturity on nutritive value of field-cured hays from common vetch and hairy vetch

Abstract

-Hay samples from common vetch and hairy vetch were collected at three maturity stages (bloom and two stages during pod-filling) with the aims of assessing the optimum harvesting stage and comparing the nutritive value of the two species. As maturation progressed, the hay content in cell wall increased and that of CP decreased. The two species showed different patterns in line with the maturing process, regarding digestibility of nutrients and effective degradability of DM and CP. Common vetch hay showed a progressive decrease of digestibility and degradability values in line with the maturing process of vegetative structures. Hairy vetch hay, however, showed a compensatory effect produced by an increasing grain proportion at later maturity stages. The nutritive value at flowering was higher for common vetch hay than for hairy vetch hay, but the opposite was observed at the stage of mature legumes. Voluntary DM intake was not affected by the species or harvest stages. Degradation studies, carried out by the nylon bag technique, showed that in these hays CP was extensively rumen degraded. Consequently, their digestible bypass protein should be low. common vetch hay / hairy vetch hay / digestibility / maturity / rumen degradability Résumé -Effets du stade de maturité sur la valeur nutritive des foins de vesce commune et de vesce velue. Une étude comparative sur la qualité des foins de vesce commune et de vesce velue, recoltés à trois stades de végétation (floraison et deux stades pendant la formation des gousses) a été conduite avec le but d'établir le stade optimal de coupe et de comparer la valeur nutritive des deux espèces. Au cours de la maturation des légumes, la teneur en parois cellulaires des foins a augmenté et celle des MAT a diminué pour les deux espèces, mais les évolutions de la digestibilité des diffé-rents constituants et de la dégradabilité de la MS et des MAT ont été différentes. La digestibilité et la dégradabilité du foin de vesce commune ont diminué progressivement avec la maturation des M. Haj Ayed et al. 32

Rumen degradability of some feed legume seeds

“…The respective ED values obtained by Valdes et al [27] were 78.1, 73.1, and 71.3. On the other hand, the ED value observed for hairy vetch was similar to that expected from the evolution in this forage through the pod-filling of the ED of CP [14]. Most results of Vicia faba (Tab.…”

Chemical composition and forage yield of threeViciavarieties (Viciaspp.) at full blooming stage

“…Ayed et al (2001) also showed that narbon vetch had the highest dry matter yields among the species studied. Narbon vetch adapts to stresses resulting from dry condition better than the other vetches.…”

Pulses and their By-Products as Animal Feed

“…The nutritive value at flowering was higher for common vetch hay than for winter vetch hay, but the opposite was observed at maturity. Voluntary DMI was not affected by the species or harvest stages (Haj Ayed et al, 2001). Haj Ayed et al (2001 observed that in sacco N degradability is quite high at flowering (78 percent effective degradability) and decreases with maturity (65 percent at seed filling).…”

“…Common vetch hay is a valuable forage with an OM digestibility of 69 percent and a CP content close to 20 percent (DM basis; Table 11.1). Haj Ayed et al (2001) observed that common vetch hay shows a progressive decrease in digestibility and degradability as its vegetative structures mature, unlike winter vetch (Vicia villosa Roth), which benefits from a compensatory effect produced by increasing grain proportions as the plant ages. The nutritive value at flowering was higher for common vetch hay than for winter vetch hay, but the opposite was observed at maturity.…”