Timelike and spacelike Ricci collineation vectors in string fluid

We study the consequences of the existence of timelike and spacelike Ricci collineation vectors (RCVs) for string fluid in the context of general relativity. Necessary and sufficient conditions are derived for a space-time with string fluid to admit a timelike RCV, parallel to ua, and a spacelike RCV, parallel to na. In these cases, some results obtained are discussed.