HEALTH ASSESSMENT OF WILD LOWLAND TAPIRS (TAPIRUS TERRESTRIS) IN THE HIGHLY THREATENED CERRADO BIOME, BRAZIL

Over 2 yr, we assessed the health of 35 lowland tapirs (Tapirus terrestris) in the Brazilian Cerrado (CE) biome, an area that is highly affected by human activities. This involved physical examinations, hematology and blood biochemistry, urinalysis, fecal parasitologic evaluation, microbial profiling of anatomic cavities and lesions, and serologic surveys for evidence of infectious agents. Research methods closely resembled those used in previous tapir health assessments in the Atlantic Forest (AF) and Pantanal (PA) biomes, allowing for a comparison among the three populations. Although not reaching statistical significance (P>0.05), tapirs from the CE exhibited poorer body and skin condition as compared to animals from the AF and PA. Furthermore, there were higher prevalences of dental problems and traumatic lesions as compared to those from the AF and PA. Eight of the 12 hematologic parameters evaluated and 17 of the 30 biochemical parameters differed significantly (P<0.05) between the tapirs from CE and those from the AF and PA. We isolated 24 different microbiologic strains from swabs of anatomic cavities and dermal lesions, of which five taxa had not previously been found in the AF or PA. We detected serum antibodies to Leptospira interrogans, bluetongue virus, and porcine parvovirus. Overall, our results suggested that tapirs from the CE exhibited more health abnormalities than tapirs in the AF and PA, possibly due to a greater exposure to environmental disturbances in the area.

Relaxin concentrations in serum and urine of endangered species: correlations with physiologic events and use as a marker of pregnancy

Many mammalian species are facing extinction due to problems created by human encroachment, agriculture, pollution, and willful slaughter. Among those at risk are the Asian and African elephant, Sumatran rhinoceros, and giant panda. Conservation groups try to save species in the wild by preserving habitat and limiting animal-human conflicts, often with limited success. Another alternative is to preserve the extant gene pool through captive breeding as a hedge against extinction. Measurement of circulating reproductive hormones is impractical for most wildlife species; determination of urinary or fecal hormone metabolites provides a more viable approach. To aid breeding management, one important tool is the ability to diagnose and monitor pregnancy, especially in species with long gestations (e.g., rhinos over 15 mo and elephants over 20 mo). Unfortunately, measuring progestins often is not useful diagnostically, because concentrations are similar during at least part of the pregnancy and the nonpregnant luteal phase in some species (e.g., elephants, rhinoceroses, and giant pandas). As serum relaxin reliably distinguishes between pregnancy and pseudopregnancy in bitches, relaxin measurement might also provide a method for detecting a successful pregnancy in endangered species. Appropriate immunoassay reagents have enabled the estimation of relaxin concentrations in the serum of elephants and rhinos and the determination of pregnancy establishment and the outcome. Relaxin was also detected in panda serum and urine. However, the extreme variability of the time between observed mating and parturition and the confounding factors of delayed implantation, pseudopregnancy, and frequent fetal resorptions made it impossible to use the panda relaxin data as a specific marker of pregnancy.

Measurement of urinary oestrogens and 20 alpha-dihydroprogesterone during ovarian cycles of black (Diceros bicornis) and white (Ceratotherium simum) rhinoceroses

The development of a sensitive enzyme-immunoassay for 20 alpha-dihydroprogesterone (20 alpha-DHP) and its use in determining reproductive status in black and white rhinoceroses is reported. 20 alpha-DHP in hydrolysed urine diluted in parallel to standards, and high-performance liquid chromatography (HPLC) confirmed the presence of 20 alpha-DHP and the absence of pregnanediol-3 alpha-glucuronide (PdG) in urine collected from rhinoceroses after oestrus. Conjugated oestrone was identified by HPLC as the major urinary oestrogen in the black rhineroceros and conjugated oestradiol-17 beta was the most abundant in the white rhinoceros. In African species, the black (Diceros bicornis), and northern (Ceratotherium simum cottoni) and southern (Ceratotherium simum simum) white rhinoceroses, excretion of 20 alpha-DHP and oestrogen followed a cyclic pattern. Excretion of 20 alpha-DHP was low before mating, at the time of peak oestrogen excretion, but high after oestrus. In the black rhinoceros, the follicular phase was 3-4 days and the luteal phase was 18 days, suggesting a cycle of 21-22 days. The interoestrus interval in the northern subspecies of white rhinoceros was 25 days, which correlated well with the interval between peaks of oestradiol-17 beta excretion. The interval between urinary oestrogen peaks in the southern subspecies of white rhinoceros suggested a cycle length of 32 days. This paper provides the first description of the pattern of excretion of urinary oestrogens and progesterone metabolites in African rhinoceroses.

Urinary androgen concentrations and social status in two species of free ranging zebra (Equus burchelli and E. grevyi)

In both species of zebra, breeding males had higher urinary androgen concentrations (ng androgens/mg Cr) than did non-breeding bachelor males (30.0 +/- 5.0 (N = 9) versus 11.4 +/- 2.8, (N = 7) in the plains zebra; 19.0 +/- 2.2 (N = 17) versus 10.7 +/- 1.2 (N = 14) in the Grevy's zebra). In the more stable family structure of the plains zebra (single male non-territorial groups) variations in androgen concentrations could not be ascribed to any measured variable. In the Grevy's zebra, androgen values were significantly lower in samples taken from territorial (breeding) males which had temporarily abandoned their territories (N = 4) and the urinary androgen concentration for a male on his territory was negatively correlated with the time since females last visited the territory.

Estrogen excretory patterns in the Indian rhinoceros (Rhinoceros unicornis), determined by simplified urinary analysis

Daily urine samples obtained at random from 3 mature Indian rhinoceroses (Rhinoceros unicornis) were evaluated for immunologic estrogen concentration and were indexed by creatinine (Cr) concentration. Chromatographic separation and enzyme hydrolysis of the estrogenic components indicated that the major urinary estrogen in this species is immunoreactive estrone (greater than 95%). Cyclic variations of immunoreactive estrogens (basal values of 0.1 to 0.3 microgram/mg of Cr. peak values of 5.8 to 12.5 microgram/mg of Cr) were observed at an interval of 43 +/- 2 days (4 cycles) which appear to reflect the apparent ovarian cycles. The method presented offers a practical approach for the monitoring of ovarian events in large, nontractable species.