| Summary: | 碩士 === 國立中興大學 === 獸醫學系暨研究所 === 98 === Formosan sambar deer (FSD, Cervus unicolor swinhoei) is a tropical cervids; a subspecies native to Taiwan, however, there is still a paucity of scientific documents regarding reproductive hormone profiles and dystocia related factors in FSD. The aim of this study was to investigate the fecal progesterone (FP4) profile during estrous cycles and gestation, and secondly, to investigate predisposing factors to dystocia and assess the feasibility of veterinary assisted deliveries via a retrospective survey of 22 dystocia cases in semi-domesticated female FSD. A total of 4 deer farms in Nantou County were used for the experiment 1. FP4 concentration was extracted and analyzed using enzyme-linked immunosorbent assay (ELISA). Twenty-two records of dystocia from 19 FSD farms over a 9-year period (2000 - 2008) were used for the experiment 2. The results of experiment 1 indicated that the modified mean estrous cycle length was 21.8 ± 0.7 days (n = 17), with a range of 14 - 25 days. Estrous behavior in female FSD was coincident with low FP4 concentration. During each pregnancy stage, pregnant hinds could be differentiated from those non-pregnant by FP4 concentration. FP4 concentration during early pregnancy was significantly lower than that in late pregnancy in all samples analyzed (p < 0.0001). The mean length of gestation was 259.1 ± 1.3 days (n = 41), which did not differ between male and female fawns (p > 0.05). A total of 46 fawns were born during study period, in which there was a sex ratio of 1.88 in favor of males. The percentage of male fawns was significantly higher than that of female fawns (65.2 % vs 34.8 %) (p < 0.05). The results of experiment 2 indicated that occurrence of dystocia and birthweight of fawn were not affected by maternal body condition (p > 0.05). Fawn mortality and hind mortality did not differ between primiparous and multiparous hinds. Sixteen fawns did not survived from the 22 dystocia cases, in which a large percentage (81.8%) were male fawns. In 12 of the cases where death occurred, the requests for veterinary assistance were delayed at least one day. However, there were 6 successful cases with surviving hinds and fawns, these were assisted within 6 hours after the onset of parturition. It was also noted that 40.9% of the dystocia resulted from maternal excitement, mainly due to human-caused disturbance. The comprehensive results of this study showed that FP4 profiles could be analyzed to predict estrous behavior and to monitor ovarian function in female FSD. Additionally, pregnancy diagnosis could be performed in early pregnancy via FP4 determination. Environmental stress might play an important role in the occurrence of dystocia and should be avoided through appropriate management practices. Veterinary assistance should be promptly requested to decrease fawn and hind mortality in dystocia case.
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