Eliciting and Characterizing Porcine Vocalizations: When Pigs Fly

Area of Science:

• Veterinary Science
• Bioacoustics
• Speech Research

Background:

• Preclinical voice research often utilizes the porcine model.
• Existing methods for inducing porcine glottic phonation are unreliable and time-consuming.
• A standardized method for assessing porcine glottic phonation is lacking.

Purpose of the Study:

• To develop and validate a novel, reliable method for inducing and recording glottic phonation in the porcine model.
• To establish a cost-effective preclinical tool for voice research.

Main Methods:

• A pulley-based apparatus and harness system were designed for "pig-lifting" with acoustic insulation.
• High-directional microphones and digital recorders were used to capture porcine vocalizations.
• Acoustic analysis (Praat, Matlab) assessed fundamental frequency (F0), intensity, duration, and cepstral peak prominence (CPP).
• Glottic phonation was defined by F0 (≥2000 Hz), duration (≥3 seconds), and perceptual judgment.

Main Results:

• The novel method consistently elicited glottic and partial-glottic phonation without requiring animal training.
• Vocalization frequency increased with repeated "pig-lifts".
• Phonation remained inducible over multiple days, though frequency decreased.
• Cepstral peak prominence (CPP) values were similar for glottic and partial-glottic phonations across the experimental period.

Conclusions:

• The developed "pig-lifting" method provides a reliable and cost-effective means to induce and record porcine glottic phonation.
• This technique serves as a valuable preclinical tool for advancing voice research.
• The method demonstrates high reliability between acoustic measures and researcher judgment.