Evaluation of Atriplex nummularia as a Roughage Source for Growing Lambs: Effects on Performance, Rumen Fermentation and Some Blood Mineral Concentrations

Abstract

This study was conducted to evaluate the feeding of Atriplex nummularia as a source of roughages for sheep. Its effects on performance, some blood minerals and ruminal fermentation activities were assessed. Fifteen growing lambs (about 30.5± 1.20 kg B.W.) were randomly allocated into three groups, each with five lambs. The animals in the first group served as a control and were fed on a basal diet consisting of concentrate mixture and wheat straw. The second and third groups were received the same basal diet with substituting the wheat straw by 50% and 100% of Atriplex nummularia hay, respectively. The animals fed the Atriplex showed a decrease in feed intake and an increase in water intake. However, the body weight was not affected in lambs fed 50% Atriplex hay of the roughage amount, but decreased in those fed on that hay alone. Feeding of Atriplex increased the total protozoa count and total VFAs in the rumen, but decreased the ammonia N concentration. The increase of VFAs production resulted in a decrease in ruminal pH values. The plasma Na level was increased in both Atriplex treatments, but the K and Cl levels were higher in lambs fed on Atriplex hay alone. The obtained results indicate that the Atriplex nummularia hay can be used as an unconventional roughage source in sheep rations. It can be included at a level reaching the half of roughage amount fed to animals without any adverse effect on body weight. Moreover, it can improve the rumen fermentation and the utilization of degradable protein in the rumen as indicated by the increase in total protozoa count and total VFAs production with reduction of ammonia N concentration in the rumen.