Knowledge of the elemental abundances of symbiotic giants is essential to address the role of chemical composition in the evolution of symbiotic binaries , to map their parent population , and to trace their mass transfer history .
However , there are few symbiotic giants for which the photospheric abundances are fairly well determined .
This is the second in a series of papers on chemical composition of symbiotic giants determined from high-resolution ( R \sim 50000 ) near-IR spectra .
Results are presented for the late-type giant star in the AE Ara , BX Mon , KX TrA , and CL Sco systems .
Spectrum synthesis employing standard local thermal equilibrium ( LTE ) analysis and stellar atmosphere models were used to obtain photospheric abundances of CNO and elements around the iron peak ( Sc , Ti , Fe , and Ni ) .
Our analysis resulted in sub-solar metallicities in BX Mon , KX TrA , and CL Sco by [ Fe / H ] \sim - 0.3 or -0.5 depending on the value of microturbulence .
AE Ara shows metallicity closer to solar by \sim 0.2 dex .
The enrichment in ^ { 14 } N isotope found in all these objects indicates that the giants have experienced the first dredge-up .
In the case of BX Mon first dredge-up is also confirmed by the low ^ { 12 } C/ ^ { 13 } C isotopic ratio of \sim 8 .