Resp Lecture 4

Front 1

What are the functions of the respiratory system?

Back 1

Gas exchange, vocalisation, olfaction (occurs in specialised area of lining of caudal part of nasal cavity), temperature control (panting=evaporation of H2O, cooling body), acid/base regulation,

Front 2

What are the components of the respiration?

Back 2

They involve both the respiratory system and the cardio system.

Front 3

What are the parts of the nose?

Back 3

External nose, nasal vestibule, paired nasal cavities, paranasal sinuses.

Front 4

What are the parts of the URT?

Back 4

Nose, nasopharynx (with associated auditory tubes), larynx, proximal trachea (to the level of the thoracic inlet)

Front 5

What are the components of the LRT?

Back 5

Trachea
Bronchi
Lungs

Front 6

Describe the nose?

Back 6

Bone case with moveable cartilaginous portion rostrally (moved by muscles).

Front 7

Dolichocephalic

Back 7

Greyhound

Front 8

Mesaticephalic

Back 8

Beagle

Front 9

Brachycephalic

Back 9

Boxer

Front 10

What compromises the external nose?

Back 10

Specialized nasal integument (skin) surrounding paired nostrils. Modified epithelium (hairless, thickened, often pigmented).
Nasal plate in carnivores, small ruminants
Nasolabial plate (ox) extends down to the upper lip
Rostral plate in the pig. Pig contains rostral bone
Philtrum
Nasal plate kept moist in some species (ox, pig, underlying glands; dog overflow from nasal cavity)

Front 11

Describe the nasal vestibule

Back 11

Narrow passage from the nostril to wider nasal cavity
Mucucutaneous junction within the vestibule-site of opening of lateral nasal gland ducts (and naso lacrimal duct in horses)

Front 12

Describe the nasal vestibule in the horse?

Back 12

Divided into dorsal and ventral parts.
Dorsally-nasal diverticulum-false nostril
Ventrally-true nostral leading to nasal cavity

Front 13

Describe the nasal cavity?

Back 13

Conducts air from the nostrils to the nasopharynx. Helps to prepare air for passage further down. The whole upper respiratory tract has a mucosal lining to filter the air; it's sticky and traps particles. Also helps to moisten air before the lungs
Housed by bony casing divided in the midline by nasal septum
Floor (hard palate) separates nasal from oral cavity.
Caudally limited by eythmoid bone
Bony casing extended rostrally by nasal cartilages.
Divided into small passages by conchae
Communicates with nasophynx through choana

Front 14

What are the nasal cartilages?

Back 14

Form the framework of mobile part of the nose
Include: Septal cartilage (rostral), several paired cartilages forming dorsal and lateral walls.
Moved by levator nasolabialis and caninus, innervated by CN VII
The muscle action to elevate the lateral wing of the nostril, increases the diameter and increases airflow.

Front 15

Nasal conchae

Back 15

Opening through which air passes from nasal cavity to nasopharynx. Delicate scrolls of bone, covered in mucosa, projecting into the nasal cavity from the dorsal and lateral walls.
Three conchae: dorsal, ventral, and ethmoidal
Function is to increase the surface area for heat exchange filtration and humidification of air by nasal mucosa and for olfaction
Divide nasal cavity into dorsal, middle, ventral, and common nasal meatuses

Front 16

Dorsal conchae

Back 16

single elongated scroll

Front 17

Ventral conchae

Back 17

Ventral-rostral part of nasal cavity. Double scroll in most species (horse single scroll)
Dog complex, filling ventral part of nasal cavity

Front 18

Ethmoidal conchae

Back 18

Numerous fine bony scrolls, attached to ethmoid bone and lateral and dorsal walls at the caudal end; supports olfactory mucosa

Front 19

What is the lateral nasal gland?

Back 19

Only in carnivores, responsible for wetness of nose.
Large serous gland between mucosa and maxillary bone in lateral wall.
Ducts open in lateral wall of nasal vestibule
Secretions important in wetting nose.

Front 20

What is the nasolacrimal duct?

Back 20

Duct which drains tears from eye to rostral part of nasal cavity.
Proximal openings at medial canthus of eye, runs within lateral wall of nasal cavity, distal opening in nasal vestibule at mucutaneous junction in horse; just ventral to alar fold in dog.

Front 21

Paranasal sinuses

Back 21

Diverticula (outpocketings) of nasal cavity into skull bones
Develop post birth and increase with age.
Lined with normal secretory nasal epithelium
Drainage of secretions through small openings into nasal cavity which can be blocked by mucus debris or congestion.
Location and size vary, but frontal and maxillary present in all.
Functions to lighten the skull while allowing bony development for muscle attachment (helps increase surface area). Probably thermal and mechanical protection of soft tissues, resonance of voice.

Front 22

Frontal sinuses

Back 22

Drain into the ethmoid region (except horses)
Extend into conual process (base of the horn) in ruminants

Front 23

Maxillary sinuses

Back 23

Communicate with nasal cavity through nasomaxillary opening (except in dog and cat-->wide opening)
In carnivores, not proper sinus, very open to the remainder of the nasal cavity, it's the place where the nasal gland sits.
Houses the roots of the upper cheek teeth
In some species further diverticula into adjacent bones (the space may get larger in species whose teeth continue to erupt)

Front 24

Maxillary sinuses in the horse

Back 24

Rostral and caudal divisions which have their drainage point in the common maxillary sinus (dorsal part)
Partly filled with unerupted cheek teeth

Front 25

Frontal sinus in horses

Back 25

Doesn't drain directly into the nasal cavity, drains into the dorsal concha (which is closed off from the nasal cavity; most species its open). Drains into caudal maxillary sinus

Front 26

What is different about the horses sinuses?

Back 26

Drainage of all sinuses into nasal cavity through narrow common nasomaxillary opening located dorsally (horse needs to move head to drain sinuses).

Front 27

Describe the bird nose

Back 27

Nostrils located in upper beak, usually at base.
Cere-soft keratinized tissue at base of upper beak
Nasal cavity compressed laterally by large orbits
No soft palate, no nasopharynx. Elongated medial choana (closes during swallowing)

Front 28

Describe the infraorbital sinus in the bird nose

Back 28

Diverticulum enclosed by caudal concha. As in mammals, inflammation can cause problems.

Front 29

Nasal gland in the birds

Back 29

Located in the lateral wall of the nasal cavity. Secretes sodium in marine birds