ABSTRACT: Purpose: The miRNA profiles were compared among groups of chronic stress exposure and control in two different breeds to identify the differentially expressed miRNAs related to response to chronic stress in the pituitary-adrenal axis. Methods: 6 male adult CFD and 6 Beagles were chosen at random with the similarities in good health, weight and other aspects. Separately, 3 of these two breeds were freely selected for the stress exposure via intermittent electrical stimulation and restraint stress, while the other 3 of these two breeds were non-disposed for normal control.The details for the disposal of dogs were: every morning dogs were restrained and electrical stimulations were exerted with a stable current of 10 mA for 6 s and then with a 6 s interval, lasting for 20 min every day. The duration of disposal was ten days.ll 12 dogs were killed by air embolism in the 11th day. Subsequently, pituitary and adrenal cortex tissues were fast collected and isolated for further high-sequencing. Results: 8 small miRNA libraries were constructed for miRNA-seq. A number of reads ranging from 15,926,611 to 81,028,035 was obtained in those 8 groups.a total of 29 (7 up, 22 down), 37 (16 up, 21 down), 30 (22 up, 8 down), 23 (16 up, 7 down), 21 (15 up, 6 down), 50 (11 up, 39 down), 28 (6 up, 22 down) and 40 (29 up, 11 down) DE-miRNAs (P-value < 0.001, log2(Fold_change) >1) were detected in the comparisons of BAC1_vs_BAC2, BAC1_vs_CFDAC1, BAC2_vs_CFDAC2, CFDAC1_vs_CFDAC2, BP1_vs_BP2, BP1_vs_CFDP1, BP2_vs_CFDP2 and CFDP1_vs_CFDP2, respectively Conclusions: Our results shed light on the miRNA profiles with and within chronic stress exposure in adrenal cortex and pituitary. Adrenal cortex and pituitary miRNA profiles of adult Chinese Field Dog and Beagle under chronic stress exposure and normal control, including BAC1 (Beagle adrenal cortex with disposal), BAC2 (Beagle adrenal cortex with non-disposal), BP1 (Beagle pituitary with disposal), BP2 (Beagle pituitary with non-disposal), CFDAC1 (Chinese Field Dog adrenal cortex with disposal), CFDAC2 (Chinese Field Dog adrenal cortex with non-disposal), CFDP1 (Chinese Field Dog pituitary with disposal), CFDP2 (Chinese Field Dog pituitary with non-disposal), were generated by deep sequencing, using Illumina Hiseq 2000.