Animal Nutrition and Feed Technology

Present study was conducted to examine the effect of spirulina (Spirulina platensis) supplementation on nutrient intake, digestibility and rumen fermentation pattern in growing Barbari goats. Eighteen male Barbari goats were divided into three groups, G1 (Control), G2 and G3 (treatment) of six animals each in completely randomized design. All the animals were fed with complete pellet feed having Bengal gram straw and concentrate mixture in 60:40 ratio. In G1 no spirulina was supplemented while in G2 and G3 spirulina was supplemented at 0.25 and 0.50% of DM, respectively. Experimental feeding durations was 90 days. After 60 days of experimental feeding, a metabolism trial of six days collection period was conducted to determine nutrients balance. Rumen liquor samples were collected from each animal at the end of experimental feeding 4h post feeding. The digestibility (%) of dry matter, organic matter, ether extract and total carbohydrate was similar among groups. The digestibility (%) of different fibre fractions (neutral detergent fibre, acid detergent fibre, cellulose and hemi cellulose) was similar in groups. Animals of control and treatment groups were in positive nitrogen balance. Concentration of total volatile fatty acids (mmol/dL SRL) in rumen fluid was statistically similar in goats of G1 (20.75), G2 (24.93) and G3 (20.37). No significant difference in total volatile fatty acid fractions was observed between control and treatment groups. There was no significant difference (P>0.05) in total nitrogen and non-protein nitrogen between control and treatment groups. TCA-precipitable nitrogen showed no significant difference among groups. Ammonia nitrogen (mg/dL SRL) showed significant difference in between control and treatment groups, highest for G1 (29.16) and lowest for G3 (16.80). From present study, it can be concluded that supplementation of spirulina @ 0.25 and 0.50 of DMI had no effect on intake, digestibility of nutrients but reduced the rumen ammonia nitrogen concentration.