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We analyse interacting galaxy pairs with evidence of tidal features in theSloan Digital Sky Survey Data Release 7 (SDSS-DR7). The pairs were selectedwithin $z<0.1$ by requiring a projected separation $r_p < 50 \kpc$ and relativeradial velocity $\Delta V < 500 \kms$. We complete spectroscopic pairs usinggalaxies with photometric redshifts considering $\Delta V_{phot} < 6800 \kms$,taking into account the mean photometric redshift uncertainty. We classify byvisual inspection pairs of spirals into co-rotating and counter-rotatingsystems. For a subsample of non-AGN galaxies, counter-rotating pairs havelarger star formation rates, and a higher fraction of young, star-forminggalaxies. These effects are enhanced by restricting to $r_p < 12 \kpc$. Thedistributions of $C$, $D_n(4000)$ and $(M_u-M_r)$ for AGN galaxies show thatcounter-rotating hosts have bluer colours and younger stellar population thanthe co-rotating galaxies although the relative fractions of Seyfert, Liner,Composite and Ambiguous AGN are similar. Also, counter-rotating hosts have morepowerful AGN as revealed by enhanced $Lum[OIII]$ values.  The number of co-rotating systems is approximately twice the number ofcounter-rotating pairs which could be owed to a more rapid evolution ofcounter-rotating systems, besides possible different initial conditions ofthese interacting pairs.

Interacting galaxies: co-rotating and counter-rotating systems with tidal tails