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Symbiotic stars (SySt) are binaries composed of a star in the later stages ofevolution and a stellar remnant. The enhanced mass-loss from the giant drivesinteracting mass exchange and makes these systems laboratories forunderstanding binary evolution. Studies of the chemical compositions areparticularly useful since this parameter has strong impact on the evolutionarypath. The previous paper in this series presented photospheric abundances for24 giants in S-type SySt enabling a first statistical analysis. Here we presentresults for an additional sample of 13 giants. The aims are to improvestatistics of chemical composition involved in the evolution of SySt, to studyevolutionary status, mass transfer and to interpret this in terms of Galacticpopulations. High-resolution, near-IR spectra are used, employing the spectrumsynthesis method in a classical approach, to obtain abundances of CNO andelements around the iron peak (Fe, Ti, Ni). Low-resolution spectra in theregion around the Ca II triplet were used for spectral classification. Themetallicities obtained cover a wide range with a maximum around ~-0.2 dex. Theenrichment in the 14N isotope indicates that these giants have experienced thefirst dredge-up. Relative O and Fe abundances indicate that most SySt belong tothe Galactic disc; however, in a few cases, the extended thick-disc/halo issuggested. Difficult to explain, relatively high Ti abundances can indicatethat adopted microturbulent velocities were too small by ~0.2-0.3 km/s. Therevised spectral types for V2905 Sgr, and WRAY 17-89 are M3 and M6.5,respectively.

Chemical abundance analysis of 13 southern symbiotic giants from high-resolution spectra at ~1.56 \mu{}m