Effect of dietary levels of neutral detergent fiber (NDF) on feed intake, nutrients digestibility, rumen parameters and nitrogen retention of beef cattle
The objective of the present study was evaluation to Effect of dietary levels of neutral detergent fiber (NDF) on feed intake, nutrients digestibility, rumen parameters and nitrogen retention of crossbred cattle (Black Angus × Zebu crossbred). It was implemented on 4 male Black Angus × Zebu crossbred cattle with an average live weight of 262±20.5 kg (Mean±SD), which were allocated in a Latin square design with 4 treatments and 4 periods. The treatments were 47, 51, 55 and 59% NDF corresponding to NDF47, NDF51, NDF55 and NDF59 treatments. Each experiment period was two weeks, 7 days for adaptation to ration and 7 days for collecting and dissecting samples. The results showed that nutrients intake (kg/animal/day) was not significantly different (P>0.05) among treatments. The DM and OM digestibility (%) were substantially different (P<0.05) among the treatments. The digestion of NDF47 treatment was not significantly higher than NDF51 and NDF55 (P>0.05), while NDF47 was substantially different for the NDF59 treatment (P<0.05). At 0h and 3h after the feeding of the beef cattle, pH value, rumen parameters and N-NH3 were not significantly various (P>0.05) among treatments. Nitrogen retention decreased from NDF47 to NDF59 treatments (P>0.05). Also, daily weight gain (g/animal/day) in the NDF47 treatment (822) was not significantly higher (P<0.05) than NDF51 (847), NDF55 (774) and NDF59 treatment (651). The above results explained that increasing NDF from 47 to 59% resulted in decreases DM and OM digestibility (P<0.05), whereas NDF47 was not significantly different with NDF51 and NDF55 treatments (P>0.05). Nevertheless, no differences were found for nutrients intake. Both nitrogen retention and daily weight gain gradually decreased. However, the NDF55 treatment was acceptable. The conclusion that NDF level was 55% in the diet was promising in the application. The likely benefit will be an increase in the utilization of fibrous roughage, rumen parameter and daily weight gain.
