OBJECTIVE: To characterize physical examination, plasma biochemical, and ultrasonographic findings in aquarium-housed, managed semiwild, and wild southern stingrays (Hypanus americanus) with and without reproductive disease. ANIMALS: Southern stingrays from aquarium (n = 48), lagoon (managed semiwild; 34), and wild (12) habitats. PROCEDURES: Limited, opportunistic prosections were performed of presumed anatomically normal wild southern stingrays and compared with findings for aquarium-housed stingrays with reproductive disease. Ultrasonographic video data from both groups were used to assign a score (1 to 5) indicating increasing severity of ovarian and uterine reproductive disease. Plasma total 17β-estradiol, estrone, progesterone, and testosterone concentrations were measured with enzyme immunoassays validated for use in southern stingrays. RESULTS: Ultrasonographic ovarian scores were significantly correlated with uterine scores. No reproductive disease was detected in semiwild or wild stingrays, but 65% (31/48) of aquarium-housed stingrays had developing or advanced reproductive disease (ie, ultrasonographic ovarian or uterine score of 4 or 5). Significant correlations were identified between ovarian and uterine disease status and plasma concentrations of all steroid hormones except testosterone. CONCLUSIONS AND CLINICAL RELEVANCE: Findings suggested that ultrasonography and plasma hormone concentrations may be useful in the identification of reproductive disease and determination of disease severity in southern stingrays.

The reproductive output of iteroparous females is influenced by parity and resource availability. To gain a better understanding of the reproductive decisions made when animals are faced with potential trade‐offs between current and future reproduction; we investigated the relationship of parity and resources availability on reproductive intervals and success by comparing the performance of primiparous and multiparous female Cape ground squirrels Xerus inauris from two study sites that differed in resource availability. Our study included the correlation of reproductive behavioral data with fecal hormonal information to establish a normative endocrine profile for pregnancy and lactation. Parity had a major influence on juvenile emergence with multiparous females having more juveniles emerge successfully. Resource availability did not influence reproductive output, either because of an interaction among multiple resource components including quantity, predictability and length of time those resources were available or because other factors (such as predation or parasitism) have a greater impact on reproductive success.