Ceacero F, Landete-Castillejos T, Bartošová J, García A J, Bartoš L, Komárková M, Gallego L
Department of Ethology, Institute of Animal Science, Praha 10-Uhříněves, Czech Republic Department of Animal Science and Food Processing, Faculty of Tropical AgriSciences, Czech University of Life Sciences. Prague 6-Suchdol, Czech Republic
Departamento de Ciencia y Tecnología Agroforestal y Genética, ETSIA, Universidad de Castilla-La Mancha. Albacete, Spain Sección de Recursos Cinegéticos, IDR, Universidad de Castilla-La Mancha. Albacete, Spain Animal Science Techniques Applied to Wildlife Management Research Group, IREC Sec. Albacete. Albacete, Spain.
J Anim Sci. 2014 Sep;92(9):4130-6. doi: 10.2527/jas.2014-7716. Epub 2014 Jul 17.
The preorbital gland plays not only an olfactory role in cervids but also a visual one. Opening this gland is an easy way for the calf to communicate with the mother, indicating hunger/satiety, stress, pain, fear, or excitement. This information can be also useful for farm operators to assess how fast the calves habituate to handling routines and to detect those calves that do not habituate and may suffer chronic stress in the future. Thirty-one calves were subjected to 2 consecutive experiments to clarify if observing preorbital gland opening is related to habituation to handling in red deer calves (Cervus elaphus). Calves were born in 3 different paddocks, handled as newborns (Exp. 1), and then subjected to the same routine handling but with different periodicity: every 1, 2, or 3 wk (Exp. 2). In Exp. 1, preorbital gland opening was recorded in newborns during an initial handling (including weighing, ear tagging, and sex determination). Preorbital gland opening occurred in 93% of calves during this procedure and was not affected by sex, time since birth, or birth weight. Experiment 2 consisted of measuring preorbital opening during the same routine handling (weighing, blood sampling, and rump touching to assess body condition) when calves were 1, 3, and 5 mo old. Binary logistic regression showed that gland opening was associated with habituation to handling, since at 1 and 3 mo the probability of opening the gland decreased with the number of handlings that a calf experienced before (P = 0.008 and P = 0.028, respectively). However, there were no further changes in preorbital gland opening rate in the 5-mo-old calves (P = 0.182). The significant influence of the number of previous handlings on the probability of opening the preorbital gland was confirmed through generalized linear model with repeated measures (P = 0.007). Preorbital gland opening decreased along the phases of the study. Nevertheless, we found a significant trend in individuals to keep similar opening patterns (intraclass correlation coefficient = 0.807, P < 0.001), which suggests that the more stressed individuals can be detected with this method. Therefore, we conclude that preorbital gland opening during routine handlings is related to the number of previous handlings, and thus it can be used as an indicator of lack of habituation to handling in farmed cervids.
眶前腺在鹿科动物中不仅具有嗅觉功能，还具有视觉功能。犊鹿打开这个腺体是与母亲交流的一种简单方式，可表明饥饿/饱腹、压力、疼痛、恐惧或兴奋。这些信息对养殖场经营者也很有用，有助于评估犊鹿适应处理流程的速度，并发现那些无法适应且未来可能遭受慢性应激的犊鹿。31头犊鹿连续接受了2次实验，以阐明观察眶前腺打开是否与马鹿（Cervus elaphus）犊鹿对处理的适应情况有关。犊鹿出生在3个不同的围场，出生时接受处理（实验1），然后进行相同的常规处理，但处理周期不同：每1、2或3周处理一次（实验2）。在实验1中，在初次处理（包括称重、打耳标和性别鉴定）期间记录新生犊鹿的眶前腺打开情况。在此过程中，93%的犊鹿出现眶前腺打开，且不受性别、出生后的时间或出生体重的影响。实验2包括在犊鹿1、3和5月龄时，在相同的常规处理（称重、采血和触摸臀部以评估身体状况）过程中测量眶前腺打开情况。二元逻辑回归显示，腺体打开与对处理的适应情况有关，因为在1和3月龄时，犊鹿打开腺体的概率随着之前经历的处理次数增加而降低（分别为P = 0.008和P = 0.028）。然而，5月龄犊鹿的眶前腺打开率没有进一步变化（P = 0.182）。通过重复测量的广义线性模型证实了之前处理次数对打开眶前腺概率的显著影响（P = 0.007）。在研究过程中，眶前腺打开情况呈下降趋势。尽管如此，我们发现个体保持相似打开模式的趋势显著（组内相关系数 = 0.807，P < 0.001），这表明使用这种方法可以检测出应激程度较高的个体。因此，我们得出结论，常规处理期间眶前腺打开与之前的处理次数有关，因此它可以作为养殖鹿科动物对处理缺乏适应的一个指标。
