A taste of space: Remote animal observations and discrete-choice models provide new insights into foraging and density dynamics for a large subarctic herbivore.

Competition for resources and space can drive forage selection of large herbivores from the bite through the landscape scale. Animal behaviour and foraging patterns are also influenced by abiotic and biotic factors. Fine-scale mechanisms of density-dependent foraging at the bite scale are likely consistent with density-dependent behavioural patterns observed at broader scales, but few studies have directly tested this assertion. Here, we tested if space use intensity, a proxy of spatiotemporal density, affects foraging mechanisms at fine spatial scales similarly to density-dependent effects observed at broader scales in caribou. We specifically assessed how behavioural choices are affected by space use intensity and environmental processes using behavioural state and forage selection data from caribou (Rangifer tarandus granti) observed from GPS video-camera collars using a multivariate discrete-choice modelling framework. We found that the probability of eating shrubs increased with increasing caribou space use intensity and cover of Salix spp. shrubs, whereas the probability of eating lichen decreased. Insects also affected fine-scale foraging behaviour by reducing the overall probability of eating. Strong eastward winds mitigated negative effects of insects and resulted in higher probabilities of eating lichen. At last, caribou exhibited foraging functional responses wherein their probability of selecting each food type increased as the availability (% cover) of that food increased. Space use intensity signals of fine-scale foraging were consistent with density-dependent responses observed at larger scales and with recent evidence suggesting declining reproductive rates in the same caribou population. Our results highlight potential risks of overgrazing on sensitive forage species such as lichen. Remote investigation of the functional responses of foraging behaviours provides exciting future applications where spatial models can identify high-quality habitats for conservation.

Genetic analyses of the parasitic nematode, Parelaphostrongylus tenuis, in Missouri and Kentucky reveal unexpected levels of diversity and population differentiation.

Wildlife translocations, which involve the introduction of naive hosts into new environments with novel pathogens, invariably pose an increased risk of disease. The meningeal worm Parelaphostrongylus tenuis is a nematode parasite of the white-tailed deer (Odocoileus virginianus), which serves as its primary host and rarely suffers adverse effects from infection. Attempts to restore elk (Cervus canadensis) to the eastern US have been hampered by disease caused by this parasite. Using DNA sequence data from mitochondrial and nuclear genes, we examined the hypothesis that elk translocated within the eastern US could be exposed to novel genetic variants of P. tenuis by detailing the genetic structure among P. tenuis taken from white-tailed deer and elk at a source (Kentucky) and a release site (Missouri). We found high levels of diversity at both mitochondrial and nuclear DNA in Missouri and Kentucky and a high level of differentiation between states. Our results highlight the importance of considering the potential for increased disease risk from exposure to novel strains of parasites in the decision-making process of a reintroduction or restoration.

A generalized fecal glucocorticoid assay for use in a diverse array of nondomestic mammalian and avian species.

Noninvasive fecal glucocorticoid analysis has tremendous potential as a means of assessing stress associated with environmental disturbance in wildlife. However, interspecific variation in excreted glucocorticoid metabolites requires careful selection of the antibody used in their quantification. We compared four antibodies for detecting the major fecal cortisol metabolites in yellow baboons following (3)H cortisol administration, ACTH challenge, and HPLC separation of fecal glucocorticoid metabolites. The most effective antibody (ICN corticosterone RIA; Cat. No. 07-120102) demonstrated relatively high cross-reactivities to the major cortisol metabolites present in feces during peak excretion, following both radiolabel infusion and ACTH challenge. This same antibody also detected increased fecal glucocorticoid metabolites after ACTH administration in the African elephant, black rhinoceros, Roosevelt elk, gerenuk, scimitar-horned oryx, Alaskan sea otter, Malayan sun bear, cheetah, clouded leopard, longtailed macaque, and northern spotted owl. Results suggest that (1) fecal glucocorticoid assays reliably detect endogenous changes in adrenal activity of a diverse array of species and (2) where comparisons were made, the ICN corticosterone antibody generally was superior to other antibodies for measuring glucocorticoid metabolites in feces.

An evaluation of the effectiveness of a videotape for discharge teaching of organ transplant recipients.

Patients' understanding of discharge teaching is an essential factor for compliance with medications and follow-up care after an organ transplant. This study compared the knowledge gained by the current method of individualized discharge teaching with that same teaching method plus a videotape. Fifty participants were assigned alternately to two groups. A written test was used to assess knowledge after teaching. Test scores indicated that the two methods were equally effective. Qualitative data gathered during interviews indicated that both groups were equally satisfied with their education. It was concluded that videotaped education is an acceptable and effective strategy when used in conjunction with other methods. Varying the medium for education will meet the unique learning needs of more patients.

Immobilization of Rocky Mountain elk with Telazol and xylazine hydrochloride, and antagonism by yohimbine hydrochloride.

Ten trapped Rocky Mountain elk (Cervus elaphus nelsoni) were successfully immobilized with a combination of 500 mg Telazol and 60 mg xylazine hydrochloride (HCl) from 9 July to 25 August 1993 in Custer State Park, South Dakota (USA). Mean (SD) dosages of 2.5 (0.6) mg/kg Telazol and 0.3 (0.1) mg/kg xylazine HCl, respectively, were administered, resulting in a mean (SD) induction time of 4.6 (0.8) min. Induction time varied with weight and dosage. Respiratory rate (breaths/min) increased following injection of Telazol and xylazine HCl and remained elevated or continued to increase through 10 min post-injection and then declined. There were no mortalities in this study. Forty mg of yohimbine HCl was used as an antagonist in eight elk, resulting in a mean (SD) recovery time of 14.0 (9.9) min when administered intravenously (n = 6), and 124.7 (9.5) min when given intramuscularly (n = 2). Recovery time varied with weight and dosage of yohimbine. Elk given 2.1 to 2.6 mg/kg Telazol and 0.1 to 0.3 mg/kg xylazine HCl responded to yohimbine HCl when administered intravenously.

Adult and pediatric peritonitis rates in a home dialysis program: comparison of continuous ambulatory and continuous cycling peritoneal dialysis.

We reviewed our 115-month experience with continuous ambulatory peritoneal dialysis (CAPD) and continuous cycling peritoneal dialysis (CCPD) in adult and pediatric patients to determine whether there is a difference in the incidence of peritonitis between patients performing CAPD or CCPD. Peritonitis rates were similar in patients performing CAPD or CCPD in both the adult and pediatric age groups. The overall CAPD peritonitis rate was significantly lower in adult patients when compared with pediatric patients. There was no difference in peritonitis rates for CCPD between adult and pediatric patients. When the data are divided into 3-year subgroups, the incidence of peritonitis is significantly lower in adult patients undergoing either CAPD or CCPD when compared with pediatric patients during the years 1986 to 1988. There is significant improvement over time in the incidence of peritonitis in both adult and pediatric patients performing CCPD; similarly, there is a trend toward improvement in patients performing CAPD. Staphylococcus species organisms remain the most common bacterial cause of peritonitis, except in pediatric patients under the age of 2 years or with nephrostomies, where gram-negative rod infections were more common. Peritonitis resulted in discontinuation of peritoneal dialysis in a greater number of adult patients. These results suggest that the number of catheter manipulations is not important in determining the incidence of peritonitis. Pediatric patients are more likely than adult patients to develop peritonitis with either CAPD or CCPD. Adult patients are more likely than pediatric patients to discontinue peritoneal dialysis secondary to peritonitis.

Carnitine status of pediatric patients on continuous ambulatory peritoneal dialysis.

Plasma carnitine and the effect of oral carnitine supplementation on serum triglycerides was studied in 12 pediatric patients receiving continuous ambulatory peritoneal dialysis (CAPD). Baseline evaluation of all patients included plasma carnitine and serum triglyceride values. Following randomization into two groups, only group 2 patients received oral L-carnitine supplementation, 100 mg/kg/day, for 2 months. The initial laboratory evaluation was repeated at the conclusion of the study. Plasma carnitine values were also determined from a control population. Mean baseline plasma carnitine concentrations of group 1 (39.8 +/- 8.0 nmol/ml) and group 2 (45.2 +/- 10.3 nmol/ml) patients were not significantly different from each other or from the control population. Serum triglyceride values were elevated in both groups (group 1 - 206.5 +/- 100.0 mg/dl; group 2 - 279.3 +/- 74.5 mg/dl). After 2 months, the mean plasma carnitine concentration of group 2 patients increased to 147.7 +/- 84.1 nmol/ml, significantly greater than the value of group 1, 32.8 +/- 8.0 nmol/ml (p less than 0.004). However, no significant change in the serum triglyceride level was noted in either group. We conclude that the plasma carnitine status of pediatric patients receiving CAPD is normal and that oral carnitine supplementation does not lead to the resolution of hypertriglyceridemia.