Improved in vitro procedure for maintaining stock cultures of three genera of rumen protozoa

¹ Department of Animal Sciences, Ohio Agricultural Research and Development Center, The Ohio State University, Wooster, Ohio 44691-4096

^* To whom correspondence should be addressed. E-mail: dehority.1{at}osu.edu.

	Abstract

In order to maintain stock cultures of rumen protozoa, studies were initiated to explore possible methods for keeping the protozoa viable without feeding every day. Cultures of Entodinium caudatum, Epidinium caudatum, Enoploplastron triloricatum, and Entodinium exiguum were used to study the effect of not feeding for 1 or 2 d. The study lasted 88 d and although concentrations decreased when not fed for 2 d (over the weekend), they recovered quickly with subsequent daily feedings. The exception was with Enoploplastron triloricatum, which showed a gradual decline over the entire study. Addition of streptomycin to the media had little effect on maintaining concentrations in all cultures except Entodinium caudatum, where the overall mean concentration was higher (P <0.01). No differences in pH or bacterial concentrations were found between cultures fed daily or those held without feed for 2 d, with or without streptomycin. For maintaining protozoa cultures (10 mL volume) over a long period of time without feeding on weekends, the following schedule is proposed: transfer and feed 0.12 mL of 1% orchard grass - 1.5% ground wheat (OGW) on Monday, feed 0.12 mL OGW on Tuesday, Wednesday and Thursday, transfer and feed 0.5 mL of OGW on Friday, do not feed on Saturday and Sunday.

Key Words: Entodinium caudatum, Entodinium exiguum, Enoploplastron triloricatum, Epidinium caudatum, in vitro culture, rumen protozoa