Refining pain management in mice by comparing multimodal analgesia and NSAID monotherapy for neurosurgical procedures.

While neurosurgical interventions are frequently used in laboratory mice, refinement efforts to optimize analgesic management based on multimodal approaches appear to be rather limited. Therefore, we compared the efficacy and tolerability of combinations of the non-steroidal anti-inflammatory drug carprofen, a sustained-release formulation of the opioid buprenorphine, and the local anesthetic bupivacaine with carprofen monotherapy. Female and male C57BL/6J mice were subjected to isoflurane anesthesia and an intracranial electrode implant procedure. Given the multidimensional nature of postsurgical pain and distress, various physiological, behavioral, and biochemical parameters were applied for their assessment. The analysis revealed alterations in Neuro scores, home cage locomotion, body weight, nest building, mouse grimace scales, and fecal corticosterone metabolites. A composite measure scheme allowed the allocation of individual mice to severity classes. The comparison between groups failed to indicate the superiority of multimodal regimens over high-dose NSAID monotherapy. In conclusion, our findings confirmed the informative value of various parameters for assessment of pain and distress following neurosurgical procedures in mice. While all drug regimens were well tolerated in control mice, our data suggest that the total drug load should be carefully considered for perioperative management. Future studies would be of interest to assess potential synergies of drug combinations with lower doses of carprofen.

Demodex carolliae in a colony of Seba's short-tailed bats (Carollia perspicillata): clinical, pathological and parasitological findings.

Seba's short-tailed bats (Carollia perspicillata) are a frugivorous species native to Central and South America. Despite their importance as a reservoir for zoonotic pathogens and their popularity in zoological collection and as research models, there are relatively few reports on non-zoonotic diseases of bats. Mites of the genus Demodex are obligate commensals of the skin of a range of mammals, are highly host-specific and are not associated with clinical disease when present in low numbers. However, infestation with high numbers can result in severe or even fatal disease and substantially affect the well-being of the animals. The clinical, pathological and parasitological findings in 12 Seba's short-tailed bats with demodicosis from a colony kept at Munich Zoo Hellabrunn between 1992 and 2021 are described in this report. From 2002, skin lesions became apparent on the head, especially the periocular region, nose and ears, as well as the genital area of some animals. In advanced cases, skin changes were also present on the abdomen, back and extremities. Gross findings typically included alopecia and thickening of the skin, with the formation of papules, reflecting cystically dilated hair follicles containing myriads of demodecid mites. Histologically, lesions were characterized by a paucicellular lymphocytic dermatitis and folliculitis with perifollicular fibrosis, epidermal hyperplasia, orthokeratotic hyperkeratosis and disproportionately high numbers of intrafollicular arthropods. Demodex carolliae was identified morphologically by light, phase-contrast and electron microscopy. Further characterization was achieved by extraction of parasitic DNA and partial gene sequencing of two mitochondrial genes, 16S rDNA and cox1. This is the first clinicopathological description of generalized demodicosis in Seba's short-tailed bats and includes the first molecular characterization of D. carolliae with provision of a GenBank entry.