Impact of Azolla Plant on Digestibility, Nutritive Value and Rumen Fermentation in Barki Sheep Diets

Abstract

The present study was conducted to evaluate azolla (Azolla pinnata) in ruminant feeding by comparing it with clover hay (CH). Twelve adult male Barki sheep, 2 years old, averaging 42.87±2.11 kg of body weight, were used in a palatability and metabolism trial. Animals were separated into two comparable groups according to their live body weight (6 animals/ group). The experimental animals were kept individually in metabolic crates. Results demonstrated that there were no significant differences between Sun-dried Azolla (SDA) and CH in dry matter content, while the content of OM, CP, and EE were significantly higher in SDA (84.16, 26.93 and 3.80%, respectively) than in CH (81.75, 14.48 and 2.70%, respectively). The content of CF % was significantly lower in SDA (13.48%) than in CH (24.82%). The results of the chemical analysis showed that SDA is rich in CP content (26.93%), which exceeds the CP content of CH (14.48%). Digestion coefficients for SDA were significantly (P<0.05) higher than CH for DM and CP, but NFE was significantly (P<0.05) lower than CH, while, CF did not differ significantly. The nutritive values (DCP and TDN %) for SDA were significantly (P<0.05) higher (18.49 and 51.93%) than CH (7.70 and 46.55), the N balance followed similar pattern being significantly (P< 0.05) higher (19.14 g N/d) than for those fed CH (7.73 g N/d), which was 2.5 times higher. Rumen characteristics (pH, VFA and NH3-N) started to be significantly (P<0.05) higher in animals fed SDA than in those fed CH after six hours of feeding. Generally, Azolla pinnata can be used successfully in Barki sheep feeding with beneficial effects on digestibility, nutritive value, nitrogen balance and rumen fermentation.