B9252 - Veterinary Cytology, Histology and Embryology

Learning outcomes

He/she knows and understand the principles of general and special Veterinary Cytology, Histology and Embryology, with particular reference to the methodologies for the study of cells and tissues and their organization. Is able to recognizes tissues in histological preparations.

Course contents

This course is part of the Integrated Course "The cell and its functions". At the end of the integrated course “The Cell and Its Functions”, the student knows cellular and tissue structure as well as the principles of general embryology, understands cellular functions, homeostatic and communication mechanisms, and is familiar with the main metabolic pathways. The student is able to identify and describe different tissue types under the microscope.

The Integrated Course contributes to the achievement of the following ESEVT Day One Competences: 1.15, 1.18, 1.29 and 1.30.

SPECIFIC TEACHING CONTENT

Module 2 - Prof. Luciana Giardino

Cytology (8 hours)

Structural organisation of the prokaryote and eukaryote cell. Cell membrane. Molecular composition and architecture of biological membranes (fluid mosaic model). Functional significance of proteins, lipids and carbohydrates in the cell membrane. Glycocalyx. Permeability and transport across the membrane: diffusion, facilitated diffusion, active transport. Exocytosis, endocytosis, phagocytosis. Active transport models: sodium and potassium pump, membrane potential. (3 hours)

Interphase nucleus: morphology and structure. nuclear envelope. Chromatin: morphology (euchromatin, heterochromatin), molecular organisation and functional activity; ADN (duplication and transcription), types of ARN and their role in transcription of the genetic code. Nucleolus: morphology and structure; nucleolar organiser, ribosome genesis. Cell cycle. (2 hours)

Cellular organelles (structure and functions): the rough and smooth endoplasmic reticulum, Golgi apparatus, lysosomes, mitochondria and peroxisomes. Cytoskeleton: microtubules, microfilaments (thin, intermediate and thick). Centriole: morphology and function. Cytoplasmic inclusions: lipid droplets, glycogen, pigment granules. (3 hours)

There are 2 hours of exercises (x 4 turns) using different types of microscopes.

Module 1 - Prof. Cristiano Bombardi

Epithelial tissues (4 hours)

Epithelial lining (2 hours)
General features. Morphological and functional polarity of epithelial cells. Classification and structural characteristics of the various types of epithelium.Intercellular junctions: occluding zonule, adherent zonule, adherent macula, gap junctions. Differentiation of the free surface of epithelia: microvilli, cilia, stereocili. Epithelium-connective junction: basement membrane.

Glandular epithelia (2 hours)
Exocrine and endocrine glands: structural and functional generalities. Morphology and structure of cells secreting proteins, glycoproteins, lipids.Exocrine glands: unicellular (gh.. mucipara or calyciform) and pluricellular. Morphological and structural organisation of the multicellular exocrine glands: morphology of the adenomere and excretory duct. Classification of the exocrine glands - according to location: intraepithelial, parietal and extraparietal; according to the shape of the adenomere (tubular, acinar, alveolar, tubulo-acinar/alveolar); according to the complexity of the excretory duct: simple and compound; according to the type of secretion: serous (proteinous), mucous (glycoproteinous) and mixed (seromucous); according to the mode of secretion emission: merocrine, apocrine and holocrine. Examples of the various types of exocrine glands.
Endocrine glands: morphological and structural organisation. Mode of action of protein, glycoprotein and steroid hormone on the target cell. Classification: chordonal, insular, follicular, interstitial. Examples of the various types of endocrine glands.

Connective or tropho-mechanical tissues (6 hours)

General organisation: cells, and intercellular substance (amorphous matrix and fibrillar component). Molecular composition of the amorphous matrix: lycoproteins, glucosoaminoglycans (GAGs), proteoglycans. Fibrillar component: morphology and structure of collagen, reticular and elastic fibres. Fibrillogenesis. Various types of collagen. (1 hour)

Connective tissue proper (1 hour)
Morphology and structure of the fibroblast and fibrocyte. Cell populations in connective tissue: macrophages, plasma cells, mast cells, melanocytes. Mesenchyme, mature mucous t.c., loose t.c., dense (or compact) regular and irregular t.c., reticular t.c. and elastic t.c.

Adipose tissue (1 hour)
Primary (or multiloculated or brown fat) and secondary (or uniloculated or yellow/white fat) adipose tissue. Morphology of the adipocyte. Histogenesis of adipose tissue. Significance of primary adipose tissue in hibernating animals.

Cartilage tissue (1 hour)
Hyaline cartilage. Chondrocyte morphology and structure. Isogenic groups. Perichondrium. Cartilage matrix: organisation in the territorial and interterritorial region. appositional and interstitial growth. Articular cartilage: arrangement of chondrocytes and fibres. Metaphyseal cartilage. Elastic cartilage. Fibrous cartilage (or fibrocartilage).

Bone tissue (2 hours)
Macro- and microscopic organisation of bone: spongy and compact. Bone tissue cells: osteoblasts, osteocytes and osteoclasts. Structure of bone tissue: interlaced fibres (non-lamellar) lamellar. Structure of lamellae: cellular and acellular.Organisation of bone lamellae: circumferential lamellae (external and internal); short radius lamellae (osteon); interstitial lamellae. Vascular canals: Havers' and Volkman's canals. Endosteum and periosteum.
Direct or intramembranous ossification.
Indirect ossification (endochondral and perichondral). Mantle ossification (of Meckel's cartilage).
Growth in thickness and length of a long bone. Bone modelling and remodelling. Mineralisation of the bone matrix.

Muscle tissue (3 hours)

Striated skeletal muscle tissue (2 hours)
Structural organisation of tissue. Muscle fibre structure. Structure of myofibrils: (sarcomere). Organisation of the sarcoplasmic reticulum. T-system. Triad. Contractile proteins and their organisation in myofilaments (thin and thick). Arrangement of myofilaments in the sarcomere. Mechanism of contraction. Histochemical typing of slow and fast fibres. Muscle fibre histogenesis and regeneration

Cardiac muscle tissue (0.5 hours)
Myocardiocyte structure. Intercalar discs. Organisation of the sarcoplasmic reticulum. T system. Dyad. Conduction tissue of the heart.

Smooth muscle tissue (0.5 hours)
Morphology and structure of the smooth muscle cell. Functional significance of caveolae, dense plaques. Smooth muscle myosin molecule. Unitary and multi-unit smooth muscle.

Nerve tissue (3 hours)
Doctrine of the neuron. Methods of staining nerve tissue. Structural and functional generalities of the neuron: excitability and conductance. Extensions of the neuron: dendrites and axon. Axon transport. Classification of neurons on morphological (number of dendrites, axon length) and functional (afferent/sensitive, efferent/motor and connecting) bases. (1 hour)

Axon sheaths: neurilemma and myelin sheath. Myelinated and amyelinated nerve fibres. Impulse conduction in myelinated fibres: (decremental and self-regenerating. Chemical synapses (structure and ultrastructure). Synaptic vesicles. Neurotransmitters.Types of synapses. Modes of operation. Electrical synapses. Motor plate.Peripheral nerve endings: free and encapsulated. (1 hour)

Glial cells

Ependymal cells, Astrocytes, Oligodendrocytes, Schwann cells and

microglia. Myelin sheath formation. (1 hour)

Blood (1 hour)
Generalities. Corpuscular elements of blood: Comparative morphology of: red blood cells, eosinophilic granulocytes, heterophils, basophils, agranulocytes (monoliths, lymphocytes). Platelets. Haemopoiesis.

Embryology (7 hours)

Fertilisation. Segmentation. Blastocyst: trophoblast, embryoblast, blastocele. Implantation. (1 hour)

Formation of primitive leaflets: didermal and tridermal stage. Formation of the primitive line, notochord and mesoderm. Delimitation of the body of the embryo. (2 hours)

Evolution of the embryonic leaflets: tissues and organs derived from the ectoderm, entoderm and mesoderm. Formation of the embryonic adnexa: chorion, amnion, yolk sac, allantois, umbilical cord. (2 hours)

Formation of the placenta with reference to different domestic mammals. (2 hours)

There will be 6 hours of exercises (x 4 turns) enabling students to observe the tissues explained in the lecture under an optical microscope.

Readings/Bibliography

The teaching materials for this course are available on the Virtuale Learning Environment (https://virtuale.unibo.it/?lang=en ).

Istologia di Valerio Monesi, 7 edizione. Piccin

Biologia-Citologia Medica (Maraldi, Tacchetti). edi-ermes.

Istologia Medica (Maraldi, Tacchetti). edi-ermes.

H. Dieter-Dellmann, Jo Ann C. Eurell, Istologia e Anatomia Microscopica Veterinaria (V edizione, traduzione italiana a cura di R. Bortolami e M. L. Lucchi. Casa Editrice Ambrosiana).

Titolo: Istologia Curato da: Rosati P., Colombo R., Maraldi N. Editore: Edi. Ermes Edizione: 5.

Pelagalli - Castaldo - Lucini - Patruno - Scocco EMBRIOLOGIA. Morfogenesi e anomalie dello sviluppo. Idelson-Gnocchi, 2008.

Teaching methods

The course consists of theoretical and practical lectures (under an optical microscope). Students with special needs are asked to contact the lecturer by email in order to better organise teaching activities and the conduct of examinations. Considering the types of activities and teaching methods adopted, attendance for this course requires the successful completion of Modules 1 and 2 via e-learning, and Module 3 on health and safety training in study environments. Information about the schedule and access to Module 3 is available in the dedicated section of the Degree Program website. Participation in practical and laboratory sessions requires wearing a lab coat and appropriate footwear. Suitable personal protective equipment (PPE), such as disposable latex gloves, will be provided as needed.

Assessment methods

This course is part of the Integrated Course "The cell and its functions". The assessment consists of a oral exam that involves the recognition of a histological preparation and three oral questions (one from Cytology, one from Histology and one from Embryology). The accuracy, completeness and expository quality in response to the questions asked are assessed. The final mark awarded to the student is derived from the average of the marks awarded to each question.

In evaluating the oral exam, the instructor will use the following grading scale:

- Basic understanding of only a few course topics; analysis skills emerge only with the instructor’s help; generally correct language → 18–22

- Limited knowledge of several topics; independent analysis only on procedural issues; correct language use → 23–26

- Broad knowledge of course topics; ability to make autonomous critical judgments; mastery of discipline-specific terminology → 27–29

- Comprehensive understanding of course content; fully independent critical analysis and connections; excellent command of terminology and argumentation skills → 30–30 with honors

The result of the oral exam will be communicated at the end of the session. The minimum passing grade is 18/30.

Final evaluation of the integrated course, registration and other useful information

The exam is considered passed only if all parts are successfully completed. The final grade is determined by the average of the grades from the various parts of the exam, expressed out of 30. A minimum final grade of 18/30 is required.

Negative results are not graded numerically but recorded as “withdrawn” or “failed” in the electronic transcript on AlmaEsami, and do not affect the student’s academic record.

Grades for individual parts and the final grade will be published on the Virtuale Learning Environment (https://virtuale.unibo.it/?lang=en ) by the designated course contact within 5 working days of the exam.

Students may reject the final grade 1 times, by informing the course examiner via email within 5 working days.

The designated course contact for this course is Prof. Cristiano Bombardi.

Students can register for exams through the AlmaEsami platform (http://almaesami.unibo.it/ ). Exams are scheduled during the designated periods in the academic calendar. Additional sessions are available for students beyond the standard program duration.

Students with learning disorders and/or temporary or permanent disabilities: please, contact the office responsible (https://site.unibo.it/studenti-con-disabilita-e-dsa/en/for-students ) as soon as possible so that they can propose acceptable adjustments. The request for adaptation must be submitted in advance (15 days before the exam date) to the lecturer, who will assess the appropriateness of the adjustments, taking into account the teaching objectives.

Teaching tools

PowerPoint , light microscopes. Lectures are supported by the projection of summary sheets, diagrams and histological preparations that are explained in detail to the students. Practical exercises take place in a classroom equipped with 40 microscopes and are supervised by the lecturer. Practice hours offer students the opportunity to observe under the microscope a collection of No. 200 histological preparations, prepared using different methods and concerning the tissues explained during the lectures. Exercise hours are an opportunity for dialogue with the lecturer in order to receive clarification on the topics covered and on the histological preparations.

In case of difficulty understanding the course content, the instructor is available for clarification meetings, which must be scheduled via email.

Office hours

See the website of Cristiano Bombardi

See the website of Luciana Giardino