Abstract
The senses of sight, smell, hearing and touch help the animals to perceive the environment and modulate their general behaviour, learning ability and social relationship. The eyes are the sensory organs that receive visual information from the environment and transmit them to the visual sensory area of the brain for interpretation.
The eyes, equipped with an adjustable pupil and a lens, capture the illumination patterns in the environment as an ‘optical picture’ on a layer of light-sensitive photoreceptor cells in the retina. The auditory system perceives the frequency of sounds as pitch and their amplitude as loudness. The external and the middle ears conduct the sound to the auditory receptors (organ of Corti) in the cochlea of the inner ear. The auditory receptors are the hair cells embedded in the basilar membrane and apical surface and convert sound wave signals into nerve impulses. Olfaction (smell) is an animal’s primary special sense perceived by the main and the accessory olfactory systems with receptors in the vomeronasal or Jacobson’s organ located near the external nares. The odorant molecules combine with odorant receptors to mediate the signal transduction mechanism leading to a series of electrical events to facilitate the sense of smell. Gustation or taste is a chemical sensation perceived through chemoreceptors in the taste buds. The skin and its derivative or accessory structures, called the integumentary system that provides a physical barrier and antimicrobial protection, involve thermo- and immuno-regulation, excretion, secretion, pigmentation, sensation and locomotion of the animal.P. Visha
Department of Veterinary Physiology and Biochemistry, Veterinary
College and Research Institute, Tamil Nadu Veterinary and Animal Sciences University, Salem, Tamil Nadu, India
P. K. Das (X) ∙ J.
Mukherjee ∙ D. BanerjeeDepartment of Veterinary Physiology, West Bengal University of
Animal & Fishery Sciences, Kolkata, West Bengal, India
© The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2023
P. K. Das et al. (eds.), Textbook of Veterinary Physiology, https://doi.org/10.1007/978-981-19-9410-4_12
Graphical Abstract
Description of the Graphical Abstract: The special senses are specialised structures in the body which provide information about the body and its environment and help the animals to modulate their general behaviour, learning ability and social relationship. It includes vision (for which eyes are the sensory organs, which receive visual information and transmit them to the visual sensory area of the brain for interpretation), hearing (the sense of sound perception occurs by the ears; it also helps in the maintenance of balance), taste (that is perceived through chemoreceptors in the taste buds of the tongue), smell (perceived by the main olfactory system and the accessory olfactory system with receptors in the nasal passages) and touch (a perception resulting from the activation of neural receptors, generally in the skin including hair follicles, but also in the tongue, throat and mucosa).
Keywords
Vision ∙ Hearing and equilibrium ∙ Smell ∙ Taste ∙ Skin
Learning Objectives
• Visual system, its components and photochemistry of vision
• Auditory system and mechanism of hearing and equilibrium
• Olfactory system and mechanism of olfaction
• Gustatory system and mechanism of taste sensation
• Skin (integumentary system) and its function
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