Age estimation of marine mammals provides important information about ecological and life history parameters. Counting growth layer groups (GLGs) in the dentine and cementum of teeth is the most common technique for age estimation in pinnipeds. In this study, we used acid‐etched canines (n = 38) and decalcified stained postcanine sections (n = 40) to calibrate readings in mummified crabeater seals (Lobodon carcinophaga). A subsample of this group received a prior cleaning treatment of boiling the teeth with hydrogen peroxide (H₂O₂). Ages ranged from 0 to 31 years. Dentine from canines and cementum from postcanines showed higher estimated ages (maximum 31 years) than dentine from postcanines (maximum 24 years), mainly in those teeth that did not receive prior treatment. Boiling with H₂O₂ has shown to affect cementum structure and, thus, results in underestimated ages, but dentine did not seem to be affected. The results presented here showed that ages can be estimated for the crabeater seal regardless of which tooth/tissue or method is used, at least for seals <13 years old. However, nontreated, stained thin sections of postcanine teeth are recommended because more reliable age estimations in older crabeater seals are obtained.

中文翻译：

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蟹嘴海豹牙齿的年龄估计和生长层模式：技术比较

海洋哺乳动物的年龄估计提供了有关生态和生活史参数的重要信息。计算牙齿的牙本质和牙骨质中的生长层组（GLGs）是最易被钳夹年龄估计的技术。在这项研究中，我们使用酸蚀犬齿（n = 38）和脱钙染色的犬齿后切片（n = 40）来校准木乃伊海豹突击队海豹（Lobodon carcinophaga）中的读数。该组的一个子样本已接受过预先清洗的过氧化氢（H ₂ O _2）煮沸牙齿的治疗。）。年龄介于0到31岁之间。来自犬齿的牙本质和来自犬齿的牙骨质的估计年龄（最长31岁）高于来自犬齿的牙本质（最长24岁），主要是在那些没有接受过治疗的牙齿中。已显示，用H ₂ O ₂沸腾会影响牙骨质的结构，因此会导致年龄被低估，但牙本质似乎并未受到影响。此处显示的结果表明，无论使用哪种牙齿/组织或方法，都可以估算出蟹形海豹的年龄，至少对于小于13岁的海豹。但是，建议使用未经处理的犬后牙齿的薄切片，因为这样可以获得更可靠的年龄估计的蟹形密封件的年龄。