Digestive System Anatomy: Mouth and Oral Cavity

• This document is about the anatomy of the digestive system, specifically the mouth, oral cavity, and pharynx in domestic animals and poultry.
• König-Liebich Veterinary anatomy of domestic animals is mandatory reading for this topic.
• Avian Anatomy : Textbook and Colour Atlas (Second Edition) is recommend for further reading.

Mouth (Os s. Stoma)

• The mouth, also known as Os s. Stoma, include the lips, oral cavity, and accessory structures like teeth, palate, tongue, and salivary glands.
• The lips are also known as Labia oris.
• The oral cavity is also known as Cavum oris.

Lips - Labia Oris

• Lips consist of skin, muscle, tendon, glands, and oral mucosa.
• Labium superius et inferius refers to the upper and lower lips.
• Rima oris means the mouth opening, or the slit between the lips.
• Commissura labiorum is the location where two lips meet.
• The Bucca is the cheek and is composed of the m.buccinator, salivary glands and loose mucosa.
• Horse (eq) lips facilitate food collection, they’re highly tactile and prehensile.
• Cows (bo) have a planum nasolabiale, or a thick, modified skin on their lips.
• Carnivores (Car) and small ruminants (cap;ov) possess a philtrum, or a medial groove in the labium superius.
• Some animals (+ca) have Papillae labiales on the margin of the lower lip.
• Pigs (su) have a planum rostrale, a rostral plate or disc that’s a fusion of the labium superius and rostrum.

Oral Cavity - Cavum Oris

• The oral cavity has two parts: the vestibule and the proper oral cavity.
• Vestibulum oris refers to the vestibule.
• The vestibulum labiale is the space between the teeth and lips or the labial vestibule.
• The vestibulum buccale is the space between the teeth and cheeks, also known as the buccal vestibule.
• Cavum oris proprium refers to the proper oral cavity, space within the dental and limited caudally by the Arcus palatoglossus.
• The proper oral cavity includes the palate (palatum), teeth (dentes), tongue (lingua), and salivary glands.
• The inner surfaces of the lips and cheeks in ruminants (Ru) feature large, backward-pointing papillae that are most prominent toward the corners of the mouth.
• Papillae labiales [1] and Papillae buccales [2] are types of papillae.
• The mucous membrane lining the oral cavity has stratified squamous epithelium, gland ducts, and submucosal glands and may be pink or pigmented.
• Gingiva, or the gums, is a modified mucous membrane attached to the teeth and alveolar bone.

Palate - Palatum

• A palatum, or palate partitions the digestive and respiratory tracts in the head, made of osseous and soft tissue.
• The Palatum durum is the hard palate supported by bone, specifically the proc. palatinus of the os maxilla, the os incisive, and the horizontal plate of os palatinum.
• The Palatum molle, or soft palate (Velum palatinum) is the caudal part of the palate.
• The oral side of the hard palate is covered by thick, cornified mucosa.
• Papilla incisive is the incisive papilla, a mucosa elevation towards the rostral end of the palatine raphe.
• Rugae palatinae are palatine ridges, paired transverse ridges decreasing in prominence.
• Horses typically have 14-16 rugae palatinae ridges.
• Raphe palati is the palatine raphe, or the median junction line of the palate halves.
• The dental pad, known as Pulvinus dentalis, is found in cows (bo) and are also known as incisive papilla.
• Cows (bo) typically have 16-18 rugae palatinae that have papillae and are directed caudally.
• Carnivores (car) have indistinct palatine raphe but have palatine ridges.
• Cats have 7-9 palatine ridges compared to Dogs who have 9-10 ridges.

Soft Palate - Palatum Molle

• The soft palate (palatum molle or velum palatinum) forms a the hard palate's caudal continuation, composed of a musculomucosal fold or flap.
• The soft palate adheres rostrally to the palatine skeleton
• The soft palate follows the contours of the tongue's root when still.

Tongue - Lingua (glossa)

• The tongue is on the ventral part of the oral cavity, composed of striated musculature, connective and adipose tissue, glands, and a thick mucous membrane.

• The M. lingualis proprius (intrinsic) is the the Fibrae longitudinales superficiales et profundae(eq), Fibrae transversae and Fibrae perpendiculares.

• Papillae linguales are lingual papillae on the dorsal surface of the tongue which vary by shape and function.

• Mechanical papillae (papillae mechanicae) include filiform, conical (papillae conicaoe), and lenticular (papillae lentiformes) types.

• Filiform papillae are absent in horses (eq).

• Gustatory papillae (papillae gustatoriae) bear taste buds and include fungiform (papillae fungiformes), vallate (papillae vallatae), and foliate (papillae foliatae) types.

• Foliate papillae are absent in ruminants (Ru).

• Radix linguae is the root and is attached to the hyoid bone.Corpus linguae is the body, dorsum linguae is the dorsal part, opposite of the palate.

• The tongue is attached to the oral floor by a mucosal fold called frenulum linguae.

• Apex linguae is the tip of the tongue, or free rostral portion.

• Cattle’s tongue (lingua, Ru) features a torus linguae, where the caudal part of the dorsum is raised.

• Fossa linguae refers to the deep pit that's rostral to the torruss

• In Ruminants, the p. filiformes papillae are on the dorsum rostral to the fosa (+p.conice+p. lenticular); on the apex.

• In Ruminants, the * p. fungiformes* papillae are numerous along the edges of the apex

• In Ruminants, p. vallatae papillae located on each side, in Ox there are (8-17); 18-24 in sheep; 12-18 in goat

• The tongue of the horse (lingua, eq) has tall lateral surfaces, is long and narrow.

• Its dorsum elevates and has bar of cartilage (cartilago dorsi linguae)

• apex is long and spatular in the horse.

• In the horse lingual frenulum is single, well developed

• The pig (Lingua (su)) tongue has a low dorsam, a narrow apex, and a double lingual frenulum.

• In pigs there are p. filiformes, p. fungiformes (over dorsal, lateral surface), p. vallatae (1 pair – at junction of body and root and p. foliatae (1 pair).

• The tongue of the Dog (Lingua ca) is highly mobile with sharp borders and a wide flat apex.

• Lyssa within the apex ventral surface.

• There is Sulcus medianus linguae median sulcus

• The tongue of the Dog has p. filiformes which are soft, p. fungiformes which are 1mm in diameter and have large taste buds, p. vallatae (2-3 pairs), p. foliatae (1 pair extemely small)

• Lyssa refers to the medial rod-like structure consisting of adipose tissue, skeletal muscle, and cartilage, found in the submucosa within the apex ventral surface.

• Sublingual floor (ca) has recessus sublingualis lateralis, caruncula sublingualis and frenulum linguae ( [e ] frenulum linguae

• The tongue of a cat (Lingua fe) has * p. filiformes* caudally directed. and hooklike and are used for firmness and for eating and grooming purposes.

• Cat tongue has *vallatae - 2-3 pairs

• cat tongue has p. fungiformes 1mm in diameter has taste buds.

• The Caruncula sublingualis projection on of frenulum

• Caruncular fold – Plica sublingualis is lateral to frenulum lingue

Salivary Glands

• The function of Salivary glands is to Provide moisture for the area it is found in the oral cavity.
• There are small and large salivary glands.
• Small salivary glands includes labial (gll. labiales), buccal (gll. buccales), zygomatic ( in carnivores)molar (cat), hard palatine (gll. palatinae) (Mollars) and Lingual (gll. linguales)
• Large salivary glands (gll. salivariae majores) some are in distance from the oral cavity.
• The large salivary glands includes Parotid (gl. parotis), mandibular (gl. mandibularis), Sublingual (gll. Sublinguales,gl.sublingualis monostomatica,)
• gl.sublingualis polystomatica.

Parotid Gland

• The parotid gland (gll. salivariae majores) is at the junction of the head and neck, ventral to the auricular cartilage and in retromandibular fossa
• the parotid duct (Ductus parotideus) Opens into oral vestibule at the top of a small papilla.
• Ductus parotideus leads to the 3ed to 5thcheek tooth depending on the species: -Dog → opposite upper 3rd cheek tooth; -Horse→ 3 rd; -Pig, small Ru → 3rd-4th; -Ox → 5th.

Mandibular Gland

• The Mandibular Gland (gl. mandibularis) is close to the angle of the jaw and partially is covered by the gl.parotis, and is bigger than the Parotid.
• Duct is Ductus mandibularis.

Sublingual Glands

• Sublingual glands (gll. sublinguales) includes gl.sublingualis monostomatica,

• gl.sublingualis polystomatica.

• gl.sublingualis monostomatica Lies under mucus of the lateral sublingual recess and lateral surface of the tongue. -Ductus sublingualis major

• gl.sublingualis polystomatica located rostrally than gl.sublingualis monostomatica

• -Ductus sublingualis minores* Is a longitudinal fold in the Recesus sublingualis lateralis

• The ductus parotideus is positioned opposite the upper M 2 molar in Ox (bo) and positioned opposite the (P3 or P4) In Cap and Ov.

Teeth

• There are parts to teeth, include * Corona dentis* Free part and * Cervix dentis* constriction is between crown and root.
• Also * Radix dentis* Is concealed by gingiva and alveolus, not covered by enamel Also it consists of Gingiva, Enamelum and Dentinum and Cementum Also pulpa dentis

Dental Surfaces

• Consists FACIES _MESIALIS AND FACIES CONTACTUS and FACIES* DISTALIS and FACIES LINGUALIS and Facies vestibularis and FACIES OCCLUSALIS

Diphylodont dentition

• The (Dentes decidui) is deciduous teeth

• The (Dentes permanentes) permanentes is teeth

• The teeth develop differently depending on the region they will go to:

• Consisting of : Incisors (dentes incisivi) (I)

• Canines (dentes canini) (C)

• Premolares (dentes premolares) (P)

• Molars (dentes molares) (M)

• The teeth of the pig are called (Dentes, su= 44) 3/ 3 C 1/1 P 4/4 M 3/3 upper, pig Dentes ca = 42) I 3/ 3 C 1/1 P 4/4 M 2/3 Upper sectorii of dog upper P4 and lower M1 → dentes

• Teeth in cat have teeth

• (Dentes,fe = 30)* Upper 3/3 C 1/1 P 3/2 M 1/1Upper canis of cat

• Teeth of HORSE canin upper is * P1 to P( P1 - dens of lupinus.

• The teeth of cattle and ruminants has dentals on the row.

• Teeth of RUMINANTS are called (Dentes, Ru = 32), I are 4 with two one side and other C is 0 two with two, molars are three with three

The Pharynx

• The pharynx is a funnel-shaped, musculo-membranous organ shared between the digestive and respiratory tracts.
• There is, tunica mucosa, that has respiratory region – pseudostratified columnar epithelium

Pharyngeal Cavity - Cavum Pharyngis

• Pars nasalis pharyngis is dorsal to the soft palate
• Pars oralis pharyngis is ventral to the soft palate
• Pars laryngea pharyngis is dorsal to the layrnx and leading into the
• The Isthmus faucium Divides oral cavity from pharynx and is the Orifice between the Cavum oris proprius and Pars opralis pharyngis, bounded by the Palatoglossal arch, soft palate, and tongue root

Poultry

• The anatomical peculiarities: The mouth, lips and teeth are absent.
• Its a Horny beak and varies depending on the species.
• The dorsal surface of the chicken tongue -smooth
• The chicken tongue is dorsal has a row of large papillae near the caudal
• The orpharnyx Is absent of
• The bird only has the Oropharynx
• The is for the bird cavity which is the esophagus

The soft palate absent in poultry

• The avian anatomy: Its a textbook and colour altas with diagrams and is adapted from Dyce, sack and Wensing and other contributators.

An overview of the anatomy of the digestive system in domestic animals and poultry, focusing on the mouth, oral cavity, and pharynx based on König-Liebich Veterinary anatomy. It includes the lips (Labia oris), oral cavity (Cavum oris), and related structures.