Abstract: Precise determination of the time of ovulation will greatly enhance the success rate of artificial insemination and timed breedings of captive marine mammals. Because daily samples are necessary to effectively monitor the estrous cycle, behavioral conditioning of blood and urine collection has greatly facilitated the development of reproductive hormone profiles of the bottlenose dolphin (Tursiops truncatus). Measuring luteinizing hormone (LH) in urine obviates the need for blood collection and increases the frequency with which samples can be obtained. This non-invasive method has the potential to elucidate the temporal associations between the fall of circulating estrogen, the surge of LH, and the time of ovulation. Daily urine samples were collected from one female bottlenose dolphin during an ovulatory estrous cycle. Urine was concentrated and normalized by osmolality before application to an immunochromatographic assay (ICG) designed to detect canine serum LH. Centrifuging urine samples to remove insoluble components enhanced the definition and visibility of LH assay bands, concentrating urine increased the speed and intensity of test band development, and normalization of samples by osmolality ensured the application of a standard concentration of urine to each assay. In this single animal cycle follow-up trial, the urinary LH profile corresponded with serum LH, estrogen, and progesterone profiles, demonstrating the possible efficacy of this method for monitoring LH.

Key Words: bottlenose dolphin, Tursiops truncatus, luteinizing hormone, reproduction, endocrinology, urine, cetacean, operant conditioning

Document Type: Conditioning for Conservation

DOI: 10.1578/AM.35.3.2009.386

Page Numbers: 386-393