No abstract

Individuals face evolutionary trade-offs between the acquisition of costly but accurate information gained firsthand and the use of inexpensive but possibly less reliable social information. American crows (Corvus brachyrhynchos) use both sources of information to learn the facial features of a dangerous person. We exposed wild crows to a novel 'dangerous face' by wearing a unique mask as we trapped, banded and released 7 -15 birds at five study sites near Seattle, WA, USA. An immediate scolding response to the dangerous mask after trapping by previously captured crows demonstrates individual learning, while an immediate response by crows that were not captured probably represents conditioning to the trapping scene by the mob of birds that assembled during the capture. Later recognition of dangerous masks by lone crows that were never captured is consistent with horizontal social learning. Independent scolding by young crows, whose parents had conditioned them to scold the dangerous mask, demonstrates vertical social learning. Crows that directly experienced trapping later discriminated among dangerous and neutral masks more precisely than did crows that learned through social means. Learning enabled scolding to double in frequency and spread at least 1.2 km from the place of origin over a 5 year period at one site.

The objective of this study was to evaluate the effect of a long-term (23-year) trap-neuter-return program on the population size of community cats in the Ocean Reef Community and to describe the demographic composition and outcome of enrolled cats. A retrospective study was performed using both cat census data collected between 1999 and 2013 as well as individual medical records for cats whose first visit occurred between 3/31/1995 and 12/31/2017. Medical record entries were reviewed to determine program inputs, cat outcomes, retroviral disease prevalence, and average age of first visit, sterilization, and death through 6/11/2018. Change over time was analyzed via linear regression. The free-roaming population decreased from 455 cats recorded in 1999 to 206 recorded in 2013 (55% decrease, P < 0.0001). There were 3,487 visits recorded for 2,529 community cats, with 869 ovariohysterectomies and 822 orchiectomies performed. At last recorded visit, there were 1,111 cats returned back to their original location, and 1,419 cats removed via adoption (510), transfer to the adoption center (201), euthanasia of unhealthy or retrovirus positive cats (441), died in care (58), or outcome of dead on arrival (209). The number of first visits per year decreased 80% from 348 in 1995 to 68 in 2017. The estimated average age of the active cat population increased by 0.003 months each year (P = 0.031) from 16.6 months in 1995 to 43.8 months in 2017. The mean age of cats at removal increased 1.9 months per year over time (P < 0.0001) from 6.4 months in 1995 to 77.3 months in 2017. The mean age of cats at return to the original location was 20.8 months, which did not change over time. The overall retrovirus prevalence over the entire duration was 6.5%, with FIV identified in 3.3% of cats and FeLV identified in 3.6%. Retrovirus prevalence decreased by 0.32% per year (P = 0.001), with FIV decreasing by 0.16% per year (P = 0.013) and FeLV decreasing 0.18% per year (P = 0.033). In conclusion, a trap-neuter-return program operating for over two decades achieved a decrease in population and an increase in population welfare as measured by increased average age of population and decreased retrovirus prevalence.

Objectives The goal of this study was to determine whether a drug combination using nalbuphine with dexmedetomidine and tiletamine/zolazepam is non-inferior to one that uses butorphanol. Methods All healthy cats presenting solely for gonadectomy to two trap–neuter–return mobile clinic days were randomly assigned to induction with a combination of tiletamine/zolazepam 3 mg/kg, dexmedetomidine 7.5 µg/kg and either butorphanol or nalbuphine at 0.15 mg/kg. All participants were blinded to the identity of the combinations. The primary endpoint was clinician satisfaction, comprised of the mean of four satisfaction ratings on a 7-point Likert scale (highly dissatisfied through to highly satisfied) recorded for induction, maintenance of anesthesia, surgery and recovery. Exploratory endpoints included each individual score, number of injections, duration of induction, duration of recovery and need for reversal agent. To assess non-inferiority for the primary endpoint and individual scores, the difference and 95% confidence intervals (CIs) of the difference between the mean clinical scores for the nalbuphine and butorphanol-based combinations were calculated and compared with a prespecified non-inferiority margin of 20% (1.4 points). Results Seventy-two cats were enrolled, 36 in each group. The mean ± SD composite score for the combination with nalbuphine was 6.06 ± 0.59 (95% CI 5.86–6.25) points, while the combination with butorphanol was 6.22 ± 0.62 (95% CI 6.01–6.43). The difference between mean scores was 0.17 (–0.12 to 0.45), which did not exceed the prespecified boundary of 1.4, establishing the non-inferiority of nalbuphine. No individual clinical score for nalbuphine was inferior to butorphanol, and there were no significant differences for any secondary endpoints. Conclusions and relevance The clinical experience of the nalbuphine-based combination was non-inferior to the butorphanol-based combination. Nalbuphine is an effective substitute for butorphanol, providing another option if butorphanol is unavailable due to shortage, controlled status or cost, without requiring a change in anesthetic workflow.