Special pathology - respiratory system Flashcards
Respiration can be divided into
- internal resp.
- external resp.
what is internal respiration
gas exchange in the metabolizing tissues
oxygen diffuses out of the blood
carbon dioxide diffuses out of the cells
what is external respiration
gas exchange in the lungs
oxygen diffuses into the blood
carbon dioxide diffuses into the alveolar air
where is the resp. center located?
and is responsible for?
in the medulla oblongata (+pons)
- automatic respiratory movements
- homeostatic response to physiological changes: regulates the rate and depth of breathing
respiratory center receives input from (3)
chemoreceptors (Co2 )
cerebral cortex
hypothalamus
the conductive system is lined by
lined by pseudostratified, ciliated columnar cells + variable proportion of secretory goblet (mucous) and serous cells
what are club cells?
Club cells (formerly known as Clara cells) are nonciliated epithelial cells found mainly in bronchioles as well as basal cells found in large airways.
contain numerous biosynthetic organelles
-active role in detoxification of xenobiotics
-critical stem cells in the repair and remodeling
-contribute to the innate immunity
mosst important portion of conductive system?
the bronchioles are the most important structures here
what were club cells formerly called?
formerly Clara cells
the respiratory exchange system is formed by?
formed by alveolar ducts and millions of alveoli
epithelial cells
type I (membranous) pneumonocytes
type II (granular) pneumonocytes
name the 2 types of pneumonocytes
type I (membranous) pneumonocytes
type II (granular) pneumonocytes
describe type I (membranous) pneumonocytes
are remarkably thin and cover most of the alveolar wall.
describe type II (granular) pneumonocytes
appear as large cuboidal cells with lamellar bodies (surfactant) in the cytoplasm.
Hypoxemia
abnormally low level of oxygen in the (aterial) blood
Hypoxia
condition in which the body or a region of the body is deprived of adequate oxygen supply at the tissue level
Normal Flora of the Respiratory System in cattle
Mannheimia haemolytica (formerly Pasteurella haemolytica) - cattle
Pasteurella multocida - cats, cattle, and pigs
Normal Flora of the Respiratory System in cats, cattle, and pigs
Pasteurella multocida - cats, cattle, and pigs
Normal Flora of the Respiratory System in dogs and pigs
Bordetella bronchiseptica- dogs and pigs
Which portions of the resp. system are considered to be essentially sterile
The thoracic portions of the trachea, bronchi, and lungs are considered to be essentially sterile.
Mannheimia (Pasteurella) haemolytica is part of the bovine nasal flora, yet this bacterium causes
a devastating disease in cattle—pneumonic mannheimiosis (shipping fever).
name 4 microbial agents
viruses
bacteria
fungi
protozoa
name 4 animal products that act as potential agents of resp. pathology
dander
feathers
mites
insect chitin
Portals of Entry into the Respiratory System (3)
Aerogenous
Hematogenous
Direct (Extension)
3 mechanisms of clearance
deposited particles are destroyed, neutralized, or removed from the mucosal surfaces
resp. system Protective mechanisms (4)
Sneezing
Coughing
Mucociliary transport
Phagocytosis
defense mechanisms of the conducting system/upper airways and bronchi (4)
antibodies
lysozyme
mucociliary clearance
mucus
defense mechanisms of the transitional system/ bronchioles (4)
antibodies
antioxidants
club cells
lysozyme
defense mechanisms of the exchange system/alveoli (4)
alveolar macrophages
intravascular macrophages
antioxidants
opsonizing antibodies
surfactant
what is the underlying pathogenetic mechanism in many pulmonary diseases
Abnormal retention of particles resulting from increased deposition, decreased clearance, or a combination of both is the underlying pathogenetic mechanism in many pulmonary diseases.
why do Very young and older animals have an increased risk of developing respiratory disease
At birth, the respiratory and immune systems are not fully developed; this makes it easier for pathogenic organisms to enter and spread within the lungs.
In aged animals, a decrease in the animal’s ability to filter out particles and fight off infection may render the lungs more vulnerable to airborne pathogenic organisms and toxic particles.
Epistaxis
blood flow from the nose, from the nasal mucosa or from deep in the lungs
Hemoptysis
blood in sputum or saliva (coughing or spitting blood)
result of pneumonia
lung abscesses
ulcerative bronchitis
pulmonary thromboembolisms or hemorrhage
pulmonary neoplasia
Rhinitis
Inflammation of the nasal mucosa
Innocuous bacteria present normally protect the host through a process called competitive exclusion, whereby potential pathogens are kept at a harmless level.
Disruption of this protective mechanism can result in rhinitis.
the organism that causes strangles
Streptococcus equi subspecies equi
or
Streptococcus equi equi
grows in the upper respiratory tract and is capable of causing infection without predisposing factors such as a previous viral disease.
an organism that causes disease of the lower respiratory tract of foals less than 5 months of age, which is slowly progressive and difficult to detect until the foal is quite sick.
Rhodococcus equi
viral disease that manifests as a mild respiratory disease in weanling foals and young racehorses
Equine Viral Rhinopneumonitis
may occur as a result of infection by either of two closely related herpesviruses, equid herpesvirus-1 and -4 (EHV-1 and EHV-4).