Effect of four mulberry (Morus alba Linn.) varieties on microbial population and fermentative products with rumen liquid from river buffaloes (Bubalus bubalis) under in vitro conditions.

The effect of four mulberry (Morus alba Linn) varieties on the microbial population and fermentative products was determined under in vitro conditions, using rumen liquid from river buffaloes (Bubalus bubalis). An in vitro fermentation was developed to evaluate five treatments: 1) 100 % of star grass (SG) (Cynodon nlemfuensis) (control), 2) SG + 30 % Cuban variety, 3) SG + 30 % Acorazonada variety, 4) SG + 30 % Tigreada variety and 5) SG + 30 % Indonesia variety. The culture and count of total viable, cellulolytic, proteolytic, amylolytic, and methanogenic bacteria and fungi were performed. Also, the count of protozoa was conducted, as well as the pH measurement and the determination of the ammonia concentration. A completely randomized design was applied with 5 x 3 factorial fit for the counts of bacteria and fungi, and with 5 x 5 for the indicators pH, ammonia concentration, and count of protozoa. The inclusion of the different mulberry varieties did not affect the populations of total viable, proteolytic, and celullolytic bacteria and fungi. At eight hours of fermentation, the treatment with the Acorazonada variety showed the lowest counts of methanogens (1.96 x 109 cfu.mL-1) compared with those including the Cuban, Tigreada, and Indonesia varieties (3.75, 3.99 and 3.70 x 109 cfu•mL-1, respectively). The counts of protozoa were superior for the Cuban variety (1.04 x 104 cel•mL-1). The pH declined, regardless the treatment, with the fermentation time, although it was always closed to neutrality. The concentration of ammonia was similar for all the treatments. It was concluded that the inclusion of 30 % of the mulberry varieties: Acorazonada, Cuban, Tigreada, and Indonesia did not affect the fiber-degrading populations or the end products of the rumen fermentation. [ABSTRACT FROM AUTHOR]