Vergleich der Zementzonenbildung im Wurzelbogen des 1. Molars mit dem Abnutzungsgrad der Backenzähne im Unterkiefer beim Reh (Capreolus capreolus L., 1758)

Evaluation of the eye lens method for age determination in roe deerCapreolus capreolus

“…In roe deer, this study is the first, to our knowledge, which evaluates the estimate precision of eye lens method on the representative and abundant material consisting of the older age classes, but we did not have the known material and the age was determined by cementum layer technique. However, tooth sectioning is considered as one of the most reli- able methods for ageing roe deer (Hell et al 1973, Aitken 1975, Üeckermann and Scholz 1986. Its results are usually applied as the "known age", and other methods or age indicators are compared with it (Klejnotowski and £abudzki 1998, Gaèiae 1999, Cicognani and Monti 2000, Mysterud and qstbye 2006.…”

“…3), because the increments of the mean eye lens weight rapidly declined already from age class 4 (7.9%). In addition, the cementum layer counting technique (CLT) appears to be more difficult for roe deer, because cementum layers of older deer were not so distinct as those in the young specimens (Hell et al 1973, Üeckermann and Scholz 1986, Gaèiae 1999). On the other hand, the study results can be under significant effect of some technical aspects, such as type and length of fixation (Hagen et al 1980).…”

“…However, at young age -where the eye lens technique works -other and quicker estimators of age could be used (eg tooth eruption patterns and presence/absence of wear characters, leg and jaw bone length). Since the number of cementum layers appeared to be an extremely accurate ageing criterion (Aitken 1975, Üeckermann andScholz 1986), the disparity between the results of CLT and ELWT methods indicated that eye lens weight can only give an approximate guide (within ± 1 years) to an individual true age.…”

“…The first molar tooth was extracted from each lower jaw and sawn in half with a fine hack-saw, polished on a fine carborundum stone, and examined by reflected light under a binocular microscope at magnification 20-30X. The accuracy of this method in roe deer was attested using animals of known age (Aitken 1975, Üeckermann andScholz 1986).…”

“…Further, this best known and most applied method is less precise compared to the cementum layer technique, because of the different degree of tooth wear which occurs between the individuals within the same age class, as well as among the individuals from distinctly different habitats (Szabik 1973, Aitken 1975. Unfortunately, the tooth sectioning technique requires more time and laboratory equipment, but also a certain experience (Hell et al 1973, Üeckermann andScholz 1986), so it cannot be employed easily and quickly for large groups of individuals.…”