Growth pattern and turnover of carbon and nitrogen measured by stable isotope ratios in the hair of sika deer (Cervus nippon)

Abstract

Rationale

Hair is known to preserve diet history and other physiological information during its growth period and is often used in chemical analyses. However, the growth patterns and turnover of hair vary according to the animal species or habitat, so understanding these patterns in the target animal is necessary for interpreting the results of hair analyses. In this study, we aimed to elucidate the growth pattern and dietary information of winter coat hair in captive sika deer (Cervus nippon).

Methods

Experiments involving hair-staining and shaving were conducted to elucidate the growth pattern of sika deer hair. A diet-switching experiment was conducted to ascertain what dietary information is reflected in the carbon and nitrogen stable isotope values of the deer winter coat. Hair samples collected from each body site (head, shoulder, back, and hip) were analyzed using an elemental analyser interfaced with an isotope-ratio mass spectrometer.

Results

The winter coat grows from early September to early November, and then stops after that. During the growth period of the winter coat, the hair of the shoulder and back grew at a constant rate. The carbon and nitrogen stable isotope values of hair reflected the deer's feeding history during hair growth, but there seemed to be a time lag in the hip hair.

Conclusions

The results suggest that the guard hair of the shoulder is suitable for hair analysis in sika deer. The obtained information on growth patterns and isotopic change of hair from captive sika deer according to diet be useful for interpreting the results of future analyses using hair samples of wild deer.