Klaus-Dieter Budras · Patrick H. McCarthy ·. Wolfgang Fricke · Renate Richter. Anatomy of the Dog with Aaron Horowitz and Rolf Berg vet vet. Anatomy of the. anatomy of the bestthing.info - Download as PDF File .pdf), Text File .txt) or read online. bestthing.info 11 - Free download as PDF File .pdf), Text File .txt) or read online for free.
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Selection was based on the utilitarian qualities of dogs which were known for their The anatomy was top priority, the knowledge of the animal's physical. Define anatomy. ▫ Discuss the different fields of anatomy. ▫ Identify and describe the integumentary system. ▫ Identify and describe the musculoskeletal system. The dog has bones. Regions of a. Long Bone. Structure of a Long Bone articular cartilage nutrient artery entering nutrient foramen marrow cavity compact .
The epidermis 1 is made up of a stratified squamous epithelium that is cornified keratinized at its surface. Thickness and degree of keratinization depend on the mechanical stress to which this layer is subject. Horn is cornified epidermis and is of varying quality in the different regions of the body. On the pads and in other regions of the skin there is soft horn. Hard horn is found at the claw.
In the skin and at the pads, the cornified cells are shed as scales owing to reduced adhesion of membrane coating materials.
At the same time, because of good adhesion as a solid mass, the horn of the claws remains restored by distal growth conical. The individual horn cell of the claw is distinctly harder than that of the skin. In areas where soft horn is formed, the epidermis exhibits a stratum granulosum between the stratum spinosum and the cornified layers. The stratum granulosum is so-named because of the keratohyalin granules that it contains.
The proteins within this layer of cells coat and glue the keratin filaments together. At individual sites additionally a stratum lucidum occurs. It consists of young, not yet differentiated, cornifying cells, the cytoplasm of which appears somewhat transparent when examined under the microscope, hence the name stratum lucidum.
anatomy of the dog.pdf
In the areas of formation of hard horn, these layers are absent, so that the cells of the stratum spinosum cornify directly without intervening strata granulosum and lucidum. The function of the epidermis consists of the replacement of cornified cells as a protection from radiation radiation absorbing pigments; see histology , from the loss and entrance of water into the body, from the entrance of parasites and for protection against trauma. With traumatic injury to the skin, healing is furthered by covering the exposed dermis by epidermal cells as soon as possible.
The dermis or corium 6 consists of a thin, loosely arranged papillary layer 2 , the papillae of which are seated in corresponding depressions of the epidermis, and a dense reticular layer 7.
The papillary layer contains mainly loosely arranged collagenous fibrils. The reticular layer consists of a plexus of coarse nondistensible collagenic fibers with a predominant course direction.
Elastic fibers are present in both layers and function to restore the typical texture of the tissue following lacerations or other distortion of the skin with respect to the cells that are found here, especially fibrocytes, fibroblasts, mast cells, plasma cells, macrophages and pigment cells, see histology. The subcutis 10 Tela subcutanea consists mainly of loose connective and adipose tissue. It is penetrated by connective tissue cords that fix the skin to the underlying fascia or periosteum.
The panniculus adiposus is the layer of fat tissue within the subcutis. Functionally, the subcutis with its subcutaneous fat tissue serves as a cushioning tissue, serves for the storage of calories and water as well as thermoregulation. Its loose connective tissue functions as a gliding layer. Where the subcutis is lacking lips, cheeks, and eyelids this gliding function is lacking and the striated musculature ends here directly in the dermis.
The blood supply of the skin is provided by larger arteries and veins of the subcutis that, owing to the mobility of the skin, have a tortuous course. They send branches to the dermis that form here two networks. The arterial network of the dermis 9 is located at the boundary with the subcutis and the subpapillary network 3 lies between the papillary and reticular layers and gives off subepidermal capillary loops into the papillary body.
The corresponding venous plexuses have a comparable location. A further subfascial vascular plexus joins the blood supply of the subcutis. The blood flow can be cut short by arteriovenous anastomoses 4 , thus avoiding the capillary bed, and in this way the vascularization of the skin is regulated.
The papillary layer is especially well supplied with blood. These vessels dilate in order to give off heat and constrict to conserve body temperature. In this way they function like the sweat glands in thermoregulation. A brachycephalic head always has maxillary brachygnathism and sometimes has mandibular brachygnathism also, and it is common to observe an anterior cross-bite in various degrees .
In fact, however, the real problem is the short maxilla; the impression of mandible prognathism is false  and can be referred to as relative prognathism . The wrong position of deciduous teeth can result in inappropriate occlusion of the permanent teeth and cause abnormal mandible or maxillary length.
This is considered to be a genetic problem . In cats, head shapes are more uniform. Basically, there are the brachycephalic breeds eg, Persian and the dolichocephalic breeds eg, Oriental see Fig. Teeth and support tissue development The primitive oral cavity is called the stomodeum. The stomodeum comprises the primary epithelial band with a dental lamina in which the tooth germs develop and a vestibular lamina in which the soft tissues develop . Brachycephalic 1 , mesocephalic 2 , and dolichocephalic 3 craniums of the dog and brachycephalic 4 and mesocephalic 5 craniums of the cat.
It begins on approximately day 30 of gestation. The bud stage initiates tooth formation when the dental lamina forms a small bud.
Crown formation occurs during the bell stage. As the roots end their development stage, the root sheath degenerates, leaving small clumps of epithelial cells epithelial rests of Malassez within the developing periodontal ligament .
The deciduous dental formula for the dog is 3 incisors I , 1 canine C , and 3 premolars PM on each mandible and maxilla total of 28 teeth. In the maxilla of the dog, the last three upper teeth have three roots, the other premolars have two roots, and the canines and incisors have just one root. In the mandible, the incisors and canines have one root and the other teeth have two roots.
In the cat, the only tooth with three roots is the upper fourth premolar. The upper and lower incisors and canines have one root, and the remaining teeth have two roots [12,14,24,28]. A study of skulls of adult domestic cats showed anatomic variation in the teeth of cats, however. Supernumerary roots were found on the maxillary third premolar teeth The lumen internal pulp space of the pulp cavity of permanent teeth rapidly decreases in size until an animal is approximately 2 years of age.
A thin or completely obliterated pulp can thus be expected in older pets. In younger animals, especially those less than 1 year of age, the pulp is much larger . The alveolar process is the portion of bone that is located around the teeth and is composed of the cortical plate, trabecular bone, and cribriform plate. The cribriform plate is know as the lamina dura on radiographs, corresponding to a thin layer of bone in the interior of the alveolus , and has many perforations for the passage of vessels to the periodontal ligament .
The trabecular bone acts like a support between the cortical plate and the lamina dura. The alveolar crest margin is the occlusal portion of the alveolar process located next to the neck of the teeth . The alveolar bone is a tooth-dependent structure. It is formed with the eruption of the teeth and is reabsorbed with extraction of the teeth. There are multiple tunnels in this bone called Volkmann canals, which are connected to the periodontal ligaments.
Tabular appendices of relational and functional anatomy
Blood vessels, lymphatics, and nerves pass into these canals . There are spaces between the teeth called interdental spaces, and the bone between the roots of the same tooth is called the interradicular septum .
The space between the third incisor and the canine is called the occlusal space . Muscles The muscles of the head are composed of six groups: facial musculature innervated by branches of the facial nerve , masticatory musculature innervated by the mandibular branch of the trigeminal nerve , tongue musculature supplied by the hypoglossal nerve , pharyngeal musculature under the control of the glossopharyngeal and vagus nerves , laryngeal musculature supplied by the vagus nerve , and eye musculature innervated by the oculomotor, trochlear, and abducent nerves .
The most important muscles manipulated by veterinarians during dental practice are discussed. The muscles of mastication are the masseter see Fig. These groups promote elevation of the mandible and permit the mouth to open, compression, and all mastication movements .
All are innervated by rami of the trigeminal nerve . The digastricus muscle is inserted in the lateral and medial portions of mandible at the ventral margins and promotes the opening of the mouth, moving the mandible in the back and down directions.
The mylohyoideus muscle is an auxiliary muscle of the tongue and mastication situated between the two medial faces of the mandible . The muscles of the tongue are the styloglossus draws the tongue backward , hyoglossus retracts and depresses the tongue , genioglossus depresses the tongue , and lingualis proprius masticatory and deglutition functions.
Lateral view of the muscles of the dog: zygomatic 1 , orbicularis oris 2 , platysma 3 , frontal 4 , sternocephalicus pars occipital 5 , sternocephalicus pars mastoidea 6 , levator nasolabialis 7 , cleidocephalicus 8 , mandibular gland 9 , parotid gland 10 , rhomboideus 11 , and masseter. ORAL ANATOMY The muscles of the soft palate are the tensor veli palatini stretches the palate between the pterygoid bones , levator veli palatini raises the caudal part of the soft palate , and palatinus shortens the palate and curls the posterior border downward.
Salivary glands There are several salivary glands working in the oral cavity. The humidity of the mouth, its digestive proprieties, and its lubrication are dependent on the saliva secreted by these glands. There are minor salivary glands on the lips, cheek, tongue, soft palate, larynx, and esophagus. The largest volume of saliva production comes from the major and compact glands, which are not located in the mouth; however, the saliva is conducted to the oral cavity by long ducts .
The major salivary glands are the parotid, mandibular see Fig. As op- posed to the minor glands, the major glands produce a serous liquid with the enzyme ptyalin, which is important in the digestion of carbohydrates .
In cats, a membranous bulge is located lingual to the mandibular molar, extending from the middle aspect to the distal aspect of this tooth. The bulge is an irregular sphere approximately 7 mm in diameter containing a small mixed salivary gland. This gland is a tubuloacinar gland with multiple small openings through several short ducts to the surface of the lingual membrane, with a predominance of mucous acini. It is divided into the ophthalmic nerve, maxillary nerve, and mandibular nerve .
The maxillary nerve is the largest ramus of the trigeminal nerve. It is responsible for the sensory perception of the cheek, nose, soft and hard palate, upper teeth, and gingiva.
In the pterygopalatine fossa, the maxillary nerve is divided into three pterygopalatine nerves: the minor palatine nerve that runs to the soft palate, together with the minor palatine artery; the major palatine nerve that runs to the palatine canal, together with the major palatine artery; and the accessory palatine nerve that runs to the caudal portion of the hard palate. Another maxillary nerve ramus is the nasal nerve, which passes to the nasal cavity by means of the sphenopalatine foramen in the pterygopalatine fossa .
After the infraorbital foramen, this nerve has multiple connections that run to the upper lips . The mandibular nerve has a motor function in the mastication muscles, especially the masseter, temporal, and digastric muscles. It contains the pterygoid nerves medial and lateral ; the buccal nerve that runs to the masseter and temporal muscles; the temporal nerve that runs to the temporal muscle; the masseter nerve that runs to the masseter muscle; the auriculo- temporal nerve that runs to the ear, parotid gland, and temporomandibular joint; the mylohyoid nerve that runs to the digastric muscle and mylohyoid muscle; and the lower alveolar nerve that passes into the mandibular canal in the mandibular foramen with a connection to the lower teeth.
This nerve forms the mental nerves, the nerves to the lower lips, and the lingual nerve to the tongue [7,28]. The ophthalmic nerve is the most important sensitive nerve of the orbit, dorsal skin of the nose, and nasal mucous and paranasal sinus, and it has three connections: the frontal, lacrimal, and nasociliary nerves . The facial nerve seventh cranial nerve acts on the facial muscles and cranial portion of the digastric muscle, salivary glands of the tongue, sublingual gland, and muscles of the oral cavity [1,7].
Vascular system The vascular system of the head depends on the external carotid artery, a bifurcation of the common carotid artery [7,11]. It may be divided into three important rami: the mandibular portion, the pterygoid portion, and the pterygopalatine portion . In the mandibular portion, the mandibular branch carries the blood supply to the temporomandibular joint with the mandibular artery .
Some care needs to be taken during surgical manipulation of this region to avoid disruption of this artery .
The mandibular alveolar artery runs into the mandibular canal, exiting the bone as the mental artery . During a mandibulectomy, much care needs to be taken to preserve the artery during osteotomy of the mandible. The two parts of the incised mandible contain the artery inside, and it needs to be ligated to avoid hemorrhage. If hemorrhage occurs, it can be controlled using bone wax .
The caudal mental artery, with its respective nerve and vein, exits the caudal mental foramen and runs to the lower lip. It is the main continuation of the alveolar artery of the mandible. The rostral mental artery is the smallest of the three mental arteries, running to the incisive-mandibular canal . The pterygoid portion has no branches. The pterygopalatine portion has important rami, including the pterygoid supplies part of the medial pterygoid , buccal large wings are distributed to masseter, temporal, and buccinator muscles terminating in the region of the soft palate and the Fig.
Intraoral radiograph of the maxilla of the dog. Lateral view of the soft tissues of the dog. The branches of the sphenopalatine artery provide extensive vasculari- zation of the dorsal and ventral nasal concha, which can cause extensive hemorrhage with trauma. When this happens, especially during nasal surgery, the region needs to be manipulated quickly and the hemorrhage controlled by compression . Intraoral view of the mouth of the dog. They run ventrally in the lateral wall of the pharynx to the soft palate, where they supply the extensive palatine glands and the palatine mucosa and muscles .
The infraorbital artery is the continuation of the maxillary artery, exiting from the pterygopalatine fossa, entering the infraorbital canal, and exiting the maxilla by means of the infraorbital foramen [1,7].
It terminates by dividing into the lateral and dorsal nasal arteries . Dental and oral anatomy on intraoral radiographs and oral anatomy of soft tissues Normal radiographic aspects of the oral cavity need to be known by veterinarians who are practicing veterinary dentistry.
Veterinarians need to be capable of recognizing normal structures and lesions so as to make a correct diagnosis . Knowledge of the normal anatomy of soft tissues is also important in identifying oral lesions. Some examples of normal structures on radiographs and in soft tissues can be observed in Figs.
References  Evans HE. The skeleton. Philadelphia: WB Saunders; La cabeza. Zaragoza: Acribia; Ishiyaku: Euro-America; Aparelho locomotor. Texto e atlas colorido. Rio Grande do Sul: Artmed; Textbook of veterinary anatomy. Nomina anatomica veterinaria.
Zurich: Manole Ltda. Function, formation, and anatomy of oral structures in carnivores. In: Small animal dentistry. Louis: Mosby; Radiographic study of the maxillary canine tooth of four mesaticephalic cats. J Vet Dent ;16 3 — Oral anatomy and physiology.
In: Veterinary dentistry. Principles and practice. Philadelphia: Lippincott-Raven; The comparative anatomy of the eye. J Am Vet Med Assoc ;— Laboratory anatomy of the cat.
Dubuque: WC Brown Company; The stomodeum comprises the primary epithelial band with a dental lamina in which the tooth germs develop and a vestibular lamina in which the soft tissues develop . Elissa Vet.
Biology questions for form five students that can lead for their excel in SPM. All dogs and all living Canidae have a ligament connecting the spinous process of their first thoracic or chest vertebra to the back of the axis bone second cervical or neck bone , which supports the weight of the head without active muscle exertion, thus saving energy. Liverpool King. Loss of the capacity Muscles innervated by axillary nerve.