Production potential of forage crops and grasses vis-a-vis sheep production system in arid region of Rajasthan

Abstract

This study evaluates the water requirements and biomass yield of five forage crops employed in sheep production systems under arid environmental conditions. For this, two forage crops, i.e., pearl millet (Pennisetum glaucum) and cowpea (Vigna unguiculata), were assessed with three perennial forage grasses, i.e., napier hybrid bajra (P. purpureum), sewan (Lasiurus sindicus), and Dhaman (Cenchrus ciliaris). These crops were evaluated in a randomized block design (RBD) with four replications during kharif 2022. The results demonstrated significant variation in growth performance and resource-use efficiency. Cowpea yielded the highest fresh biomass with the lowest water productivity. Conversely, sewan grass recorded the highest dry matter yield along with superior water productivity, highlighting its adaptability to arid conditions and efficiency of utilization of available moisture. Napier hybrid bajra and pearl millet recorded the highest plant height, measuring 200.35 and 167.20 cm, respectively, with corresponding water productivity values of 1.72 and 1.57 kg m-³. To tested their effects on livestock performance, dry fodder of napier, lasiurus and cenchrus were fed with cowpea in a 50:50 ratio in the evening hours and bajra dry fodder along with concentrate in morning hours, respectively, to lambs of G1, G2, and G3 groups (a total 21 lambs of 3 months age, average weight 14.4 kg) using a randomized block design. The feeding schedule continued over a five-week period. Significant differences (p <0.05) were observed in dry matter intake and water consumption per kilogram of feed. Lambs on a cenchrus-based diet (G3) had the lowest water intake among the tested groups. The highest body weight gain (p <0.01) was recorded in this group with the least virtual water requirement per kilogram of body weight gain (4,966.94 ± 268.50 L) and was followed by diet Lasiurus (G2) at 5,188.06 ± 190.44 L. The water requirement of the napier-based diet (G1) at 6,724.98 ± 394.20 L was found the highest. Overall, these findings highlight that C. ciliaris, in particular, demonstrated high water-use efficiency and strong potential for supporting sustainable livestock farming under water-limited conditions.