Keogh Mandy J, Thompson Daniel P, Crouse John A
Division of Wildlife Conservation, Alaska Department of Fish and Game, 802 3rd St, Douglas, AK 99801, USA.
Kenai Moose Research Center, Alaska Department of Fish and Game, 43961 Kalifornsky Beach Road Suite B, Soldotna, AK 99669, USA.
Conserv Physiol. 2023 Dec 13;11(1):coad097. doi: 10.1093/conphys/coad097. eCollection 2023.
Measurements of reproductive and stress-related hormones in keratinous tissues (e.g. hair, claws, hooves, baleen) can provide a record of stress and reproductive response in wildlife. We evaluated a method to collect keratin tissue from hooves of immobilized moose () and validated enzyme immunoassays for measuring cortisol and progesterone in hooves and hair. We also measured the annual growth and wear rates of moose hooves. Progesterone (range: 1.0-43.7 pg/mg) and cortisol (range: 0.05-2.9 pg/mg) were measurable and showed variation among hoof samples and moose. Pregnant females had twice as high progesterone concentrations (18.00 ± 3.73 pg/mg) from hoof sample locations post breeding compared to non-pregnant moose (9.40 ± 0.25 pg/mg). Annual hoof growth differed between the front (5.58 ± 0.12 cm) and rear (4.73 ± 0.13 cm) hooves and varied by season with higher growth rates during summer which decreased into autumn and winter. Adult female hooves represented between 1.6 and 2.1 years of growth and included up to two reproductive cycles. We established a method to estimate hoof growth rate and applied this to postmortem samples and were able to detect previous pregnancies. Shoulder guard hairs grew between August and March including during late gestation; however, hair progesterone concentrations (range: 2-107.1 pg/mg) were not related to reproductive state. Hair cortisol concentrations in our study (range: 0.2-15.9 pg/mg) were within the range of values previously reported for cervids. Our study supports the use of hooves for longitudinal sampling and measuring reproductive and stress-related hormones, providing a new tool for tracking reproductive events and understanding what variables may contribute to population level changes in reproduction.
对角质组织（如毛发、爪子、蹄、鲸须）中的生殖激素和应激相关激素进行测量，可以提供野生动物应激和生殖反应的记录。我们评估了一种从被 immobilized 的驼鹿（）蹄部采集角质组织的方法，并验证了用于测量蹄部和毛发中皮质醇和孕酮的酶免疫分析方法。我们还测量了驼鹿蹄的年生长和磨损率。孕酮（范围：1.0 - 43.7 pg/mg）和皮质醇（范围：0.05 - 2.9 pg/mg）是可测量的，并且在蹄部样本和驼鹿之间存在差异。怀孕雌性在繁殖后蹄部样本位置的孕酮浓度（18.00 ± 3.73 pg/mg）是非怀孕驼鹿（9.40 ± 0.25 pg/mg）的两倍。前蹄（5.58 ± 0.12 cm）和后蹄（4.73 ± 0.13 cm）的年生长量不同，并且随季节变化，夏季生长率较高，进入秋冬后下降。成年雌性蹄代表了1.6到2.1年的生长，包括多达两个生殖周期。我们建立了一种估计蹄生长率的方法，并将其应用于死后样本，能够检测到以前的怀孕情况。肩部保护毛在8月至3月期间生长，包括妊娠后期；然而，毛发孕酮浓度（范围：2 - 107.1 pg/mg）与生殖状态无关。我们研究中的毛发皮质醇浓度（范围：0.2 - 15.9 pg/mg）在先前报道的鹿科动物的值范围内。我们的研究支持使用蹄部进行纵向采样和测量生殖激素和应激相关激素，为追踪生殖事件和了解哪些变量可能导致种群水平的繁殖变化提供了一种新工具。
