| Summary: | 碩士 === 國立中興大學 === 獸醫學系暨研究所 === 96 === Formosan sambar deer (FSD, Cervus unicolor swinhoei) is a native subspecies in Taiwan and its reproductive traits remains unclear. The aim of this study was to investigate the reproductive performance of female FSD throughout the year, and secondly, to analyze their annual pattern of fecal progesterone. A total of 210 adult female FSD in four deer farms in Nantou County were used for this investigation. Extensive analyses of 525 reproductive records, including the conditions of estrus, gestation, and parturition from these hinds, were collected from 2000 to 2008. The results indicated that the mean estrus cycle was 18.2 ± 0.5 days (n = 56, varying from 10 to 25 days). The mean length of gestation (n = 288), calving interval (n = 122), and length of lactation (n = 87) were 259.6 ± 0.5 days, 369.9 ± 2.3 days, and 81.9 ± 1.3 days, respectively, indicating the characteristic of annual single parity in female FSD. The average lengths of gestation for male and female calves were 259.7 ± 0.6 days (n = 159) and 259.9 ± 0.8 days (n = 129), respectively. The length of gestation was not significantly affected by the gender of calves or twin birth. Rutting occurred from June to December (n = 494), with a peak in July/October (n = 460) (p < 0.05). Calving distributed from February to September (n = 314), with a peak in April/June (n = 261) (p < 0.05). Only one twin birth was documented in the 317 calving data (0.32%). The male/female ratio of calves (1.3:1, n = 318) differed significantly from the equal ratio (p < 0.05). Male calves had a higher gender-specific mortality rate after birth than the females (6.7% vs. 5.8%). In additions, fecal samples of 11 hinds from the Farm A and of 6 hinds from the Farm B in Nantou County were collected 3 times a week from Jan. 01 to Dec. 31, 2007, to determine their fecal progesterone (FP4) concentrations by enzyme-linked immunosorbent assay (ELISA). The hinds were considered pregnant when FP4 > 380 ng/g in the Farm A and FP4 > 130 ng/g in the Farm B, respectively. The sensitivity and specificity for the pregnancy diagnosis of hinds on days 36 - 44 after copulation were 83.3 - 100% and 100% in the Farm A, while these were 100% and 100% in the Farm B. The mean FP4 concentrations of the hinds in the different reproductive phases, including the periods of early, middle and late pregnancy, postpartum, lactation and postpartum estrus in Farm A were higher than these in Farm B (p < 0.05). The analysis of repeated measures showed that the linear model was useful to predict significantly FP4 concentrations from weeks of gestation with y = 206.30 x for Farm A (r2 = 0.5002, p < 0.05) and y = 80.17 x for Farm B (r2 = 0.2575, p < 0.05). The FP4 value of hinds in gestation was neither significantly affected by the age and parity of hinds, nor the sex of calves. Besides, the levels of FP4 started a marked decline 6.7 ± 2.4 days prior to parturition in 9 pregnant hinds (p < 0.05). In the present study, the FP4 analysis was successfully used for non-invasive monitoring of FP4 fluctuation during the pregnancy, early pregnancy diagnosis and the prediction of calving in farmed female FSD.
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