Sheep as a large animal ear model: Middle-ear ossicular velocities and intracochlear sound pressure

Péus, Dominik; Dobrev, Ivo; Prochazka, Lukas; Thoele, Konrad; Dalbert, Adrian; Boss, Andreas; Newcomb, Nicolas; Probst, Rudolf; Röösli, Christof; Sim, Jae Hoon; Huber, Alexander; Pfiffner, Flurin

doi:10.1016/j.heares.2017.06.002

Cited by 16 publications

(17 citation statements)

References 36 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…1 The general attributes of the sheep model include their quiet temperament and their size, which facilitates the evaluation of surgical techniques and human medical devices. 2 Unlike laboratory-bred specific-pathogen-free rodent animal models, most sheep in research are obtained from commercial farms where animals are exposed to routine husbandry practices with no consideration for their ultimate use in research projects. 2 Unlike laboratory-bred specific-pathogen-free rodent animal models, most sheep in research are obtained from commercial farms where animals are exposed to routine husbandry practices with no consideration for their ultimate use in research projects.…”

mentioning

confidence: 99%

“…1 Recent studies, specifically on ear disorders, and their treatments have indicated the particular utility of sheep as a large animal species with ear anatomy and physiology similar to that of humans and suited to surgical training and testing. 2 Unlike laboratory-bred specific-pathogen-free rodent animal models, most sheep in research are obtained from commercial farms where animals are exposed to routine husbandry practices with no consideration for their ultimate use in research projects. This source of sheep means their genetics, health status and signalment may not be documented to the same extent as for animals bred specifically for use in research.…”

mentioning

confidence: 99%

See 1 more Smart Citation

Reactions to Gudair® vaccination identified in sheep used for biomedical research

et al. 2019

View full text Add to dashboard Cite

Case report We report Gudair® vaccination (against ovine Johne's disease, Mycobacterium avium subsp. paratuberculosis) site reactions in sheep used as a surgical model in biomedical research and discuss the actual and potential impact these lesions may have on surgical procedures, particularly in otology. Nine female Merino-cross sheep (Ovis aries) were enrolled in a project designed to investigate the healing capabilities of the malleus bone in the middle ear. The sheep were 12-18 months of age. Eight sheep had lesions near the base of the right ear that were discovered when surgery was performed. The size of the lesions varied and all lesions had a thick capsule containing various amount of caseous material. Two lesions had a draining tract where purulent material was apparent at the lowest point. The prescapular lymph nodes were not palpable in any of the sheep. Aerobic growth of various organisms was reported from four sheep lesions when the purulent material was transferred to a broth media. Histopathological examination revealed intralesional Mycobacteria and focal caseous necrosis or granulomatous dermatitis and cellulitis in seven of the eight lesions. Mild necrotising to granulomatous dermatitis and cellulitis was described in the lesion where organisms were not found.Conclusions The lesions were confirmed at the end of the study to be associated with the vaccination and did not cause any known adverse effects on the research. However, it is important to acknowledge the risk of contamination these lesions could have on a sterile surgical site.

show abstract

mentioning

confidence: 99%

mentioning

confidence: 99%

Reactions to Gudair® vaccination identified in sheep used for biomedical research

et al. 2019

View full text Add to dashboard Cite

show abstract

“…The similarities of the middle and inner ear anatomy and physiology provided the rationale for selection of sheep as a valid model to conduct testing of implanted hearing devices for humans [ 16 , 18 , 20 , 21 ]. The front part of the scala tympani, beginning approximately 2–3 mm from the round window, is the largest cavity of the sheep cochlea and, hence, is best suited for ICAR placement.…”

Section: Methodsmentioning

confidence: 99%

“…This abrupt drop in sound pressure was identified on the reference microphone but not on the ICSP signal. Consequently, the reference microphone signal in that frequency range (4–5.5 kHz) was regarded as an unreliable interpretation of the SPL acting on the tympanic membrane and was corrected based on earlier investigations on sheep cadavers [ 18 ].…”

Section: Methodsmentioning

confidence: 99%

“…In contrast, studies have shown that sheep are a valid large animal model for research in otology that can be used as a surgical training model because of the similarity in cochlear access and to validate hearing devices for human use [ 15 , 16 , 17 ]. The sheep and human cochlea share similarities in size, shape and biomechanical performance (e.g., frequency range of hearing) [ 18 ].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Proof of Concept for an Intracochlear Acoustic Receiver for Use in Acute Large Animal Experiments

Pfiffner

Prochazka

Dobrev

et al. 2018

Sensors

Self Cite

View full text Add to dashboard Cite

(1) Background: The measurement of intracochlear sound pressure (ICSP) is relevant to obtain better understanding of the biomechanics of hearing. The goal of this work was a proof of concept of a partially implantable intracochlear acoustic receiver (ICAR) fulfilling all requirements for acute ICSP measurements in a large animal. The ICAR was designed not only to be used in chronic animal experiments but also as a microphone for totally implantable cochlear implants (TICI). (2) Methods: The ICAR concept was based on a commercial MEMS condenser microphone customized with a protective diaphragm that provided a seal and optimized geometry for accessing the cochlea. The ICAR was validated under laboratory conditions and using in-vivo experiments in sheep. (3) Results: For the first time acute ICSP measurements were successfully performed in a live specimen that is representative of the anatomy and physiology of the human. Data obtained are in agreement with published data from cadavers. The surgeons reported high levels of ease of use and satisfaction with the system design. (4) Conclusions: Our results confirm that the developed ICAR can be used to measure ICSP in acute experiments. The next generation of the ICAR will be used in chronic sheep experiments and in TICI.

show abstract

Comparative study of the external auditory canal in humans and large mammals

Wang

Yin

et al. 2021

The Anatomical Record

View full text Add to dashboard Cite

Given the limited source of human external auditory canal (EAC) skin, animal experiments remain an important approach for studying functional EAC reconstruction. However, differences between humans and animals in terms of the general EAC structure, histological characteristics of EAC skin, and cell markers of its specific glands in cartilaginous EAC skin remain unknown. We compared the characteristics of the EAC between humans and large animals, as a basis for appropriate animal model selection. Temporal bone computed tomography was used to compare the EACs of humans, goats, pigs, and dogs. EAC skin samples were harvested and their histological characteristics evaluated. The skin's ultrastructure and the histological structure of specific glands and cell markers related to cell phenotype and function were further identified. The EAC structure in goats was similar to that in humans in terms of diameter, length, and cartilaginous segment ratio of the EAC, while that of pigs and dogs differed markedly. Furthermore, histological evaluation showed that there were abundant ceruminous and sebaceous glands in the goat's cartilaginous skin, while dogs and pigs showed notably fewer of these glands in cartilaginous skin than humans. Nevertheless, ceruminous glands in all species studied showed similar expression of cell biomarkers and secretion function. Goats might have advantages in terms of surgery and reconstruction of the functional EAC skin compared to dogs and pigs and can be a useful candidate for ceruminous gland cell sources.

show abstract

Sheep as a large animal ear model: Middle-ear ossicular velocities and intracochlear sound pressure

Cited by 16 publications

References 36 publications

Reactions to Gudair® vaccination identified in sheep used for biomedical research

Reactions to Gudair® vaccination identified in sheep used for biomedical research

Proof of Concept for an Intracochlear Acoustic Receiver for Use in Acute Large Animal Experiments

Comparative study of the external auditory canal in humans and large mammals

Contact Info

Product

Resources

About