In VitroManipulation of Jersey Cow Rumen Ecology with Enzymes or Microbes Obtained from Wild Ungulates

Abstract

This study aimed to increase the amount of energy harvested by the cow system (CW) without necessarily increasing intake. Primarily, four in vitro microbial consortia N1 (cow and horse), N2 (cow and wildebeest), N3 (cow and zebra) and N4 (cow, horse, wildebeest and zebra) were created. Exocellulase, endocellulase, xylanase and cellobiase specific activities of these systems upon incubation with cellulose, carboxymethyl cellulose, xylan and cellobiose, respectively, were measured. Enzyme kinetic constant, rate of product formation and enzyme catalytic rate (Kcat) were also determined. Thirdly, in vitro microbial fermentation and degradability of milky maize stover (MS) and neutral detergent fibre (NDF) with inocula from the four systems over 72 h at 39°C were determined by measuring the amount of gas released and true degradability. Systems N4 (Kcat= 32.08) and N1 (Kcat= 16.67) were the most (P<0.05) active enzyme systems upon incubation with endocellulose with specific activity of 9.57 and 4.47 μg glucose/mg, respectively. In vitro fermentation of MS and NDF, and gas production measurements showed that system N4 was the most (P<0.05) active microbial consortium relative to CW. These results demonstrated that in vitro transfer of active enzymes or microbes from other herbivores to the cow is possible while maintaining their fibrolytic potential. Further investigation of such microbial consortia can improve livestock productions as the method is inexpensive and may be easily accessed by most farmers if established.