title: Anesthesia and blood sampling of wild big brown bats (eptesicus fuscus) with an assessment of impacts on survival.
abstract: We anesthetized and blood sampled wild big brown bats (Eptesicus fuscus) in Fort Collins, Colorado (USA) in 2001 and 2002 and assessed effects on survival. Inhalant anesthesia was delivered into a specially designed restraint and inhalation capsule that minimized handling and bite exposures. Bats were immobilized an average of 9.1+/-5.1 (SD) min (range 1-71, n=876); blood sample volumes averaged 58+/-12 microl (range 13-126, n=718). We randomly selected control (subject to multiple procedures before release) and treatment (control procedures plus inhalant anesthesia and 1% of body weight blood sampling) groups in 2002 to assess treatment effects on daily survival over a 14-day period for adult female and volant juvenile bats captured at maternity roosts in buildings. We monitored survival after release using passive integrated transponder tag detection hoops placed at openings to selected roosts. Annual return rates of bats sampled in 2001 were used to assess long-term outcomes. Comparison of 14-day maximum-likelihood daily survival estimates from control (86 adult females, 92 volant juveniles) and treated bats (187 adult females, 87 volant juveniles) indicated no adverse effect from anesthesia and blood sampling (juveniles: chi2=22.22, df=27, P>0.05; adults: chi2=9.72, df=18, P>0.05). One-year return rates were similar among adult female controls (81%, n=72, 95% confidence interval [CI]=70-91%), females treated once (82%, n=276, 95% CI=81-84%), and females treated twice (84%, n=50, 95% CI=74-94%). Lack of an effect was also noted in 1-yr return rates of juvenile female controls (55%, n=29, 95% CI=37-73%), juveniles treated once (66%, n=113, 95% CI=58-75%), and juveniles treated twice (71%, n=17, 95% CI=49-92%). These data suggest that anesthesia and blood sampling for health monitoring did not measurably affect survival of adult female and volant juvenile big brown bats.
authors.affiliation: Center for Comparative Medicine, Department of Medicine, University of Virginia Health System, and Department of Biology, University of Virginia, Charlottesville, Virginia 22904-0326, USA. jhw5b@virginia.edu
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Wimsatt
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: O'Shea
authors.forename: Laura E
authors.initials: LE
authors.lastname: Ellison
authors.forename: Roger D
authors.initials: RD
authors.lastname: Pearce
authors.forename: Valerie R
authors.initials: VR
authors.lastname: Price
mesh_terms: D000769:Anesthesia, Inhalation / Q000379:methods / Q000401:mortality / Q000662:veterinary*; D018685:Anesthetics, Inhalation; D000818:Animals; D000835:Animals, Wild / Q000097:blood / Q000502:physiology; D001800:Blood Specimen Collection / Q000401:mortality / Q000662:veterinary*; D002685:Chiroptera / Q000097:blood / Q000502:physiology*; D003120:Colorado; D005260:Female; D007530:Isoflurane; D016013:Likelihood Functions; D008297:Male; D011897:Random Allocation; D012698:Serologic Tests / Q000662:veterinary; D016019:Survival Analysis
chemical_list: D018685:Anesthetics, Inhalation; D007530:Isoflurane