3. Avian Anatomy and Physiology Pt 2 Flashcards
What is the bursa of fabricus?
the initial site of B lymphocyte production
What is different about the digestive system than other species?
birds have fast metabolism
high demand for energy is thus assimilated from food they consume
What is unique about the avian esophagus
crop = expansion over interclavicular space
a place for storage, lubrication and for passage of food
little digestion occurs
pigeons and doves: at breeding time, mucosal lining can break down to form “pigeon milk”
insect-eating birds: heavy epithelium protects from insect swallowed alive
What are the two separated compartments of the avian stomach
proventriculus = glandular stomach (chemical digestion begins here with pepsin and hydrochloric acid)
Gizzard = ventriculus = muscular stomach (striated muscles grind food, ingested grit aids in grinding food, undigested food ground into pellet by some species which is then regurgitated)
What does the liver and pancreas look like in avians?
Liver: bilobed, right lobe larger than left
Pancrease: Relatively large, especially in fish and grain eaters
rests in loop of duodenum
endocrine portion occupies more tissue mass than in animalsW
What is the duodenum’s main job for avian?
main organ for digestion and absorption of nutrients
varies in length and thickness depending on diet
What is the ceca’s job in the avian digestive system
paired sacs at junction of small and large intestines in some species
role in water reabsorption and in the bacterial fermentation of cellulose
contents excreted independent of fecal material
What is the large intestines role in the avian digestive system?
major role is reabsorption of water and minerals
What does the cloaca do? what is the 3 sections of it?
the end of the digestive tract
3 sections: coprodeum (receives excrement from intestine), urodeum (receives discharge from kidneys and genital ducts), protodeum (stores excitement and eliminates it)
Vent: muscular anus expels waste products = mute
What is mute?
combination of feces and urine
usually appears as a dark fecal center with white urates around it
varies by diet
can also be an indication of dz, therefore bird owners should monitor carefully - green mute = chlamydial infection, internal parasites or liver dz
What should we be careful about tube feeding birds?
direct feeding tube down esophagus making sure to avoid trachea; visualize back of throat as you feed to ensure there is no regurgitation
Is there anything different about the avian heart?
4 chambered, R side smler than left
lies in cranial portion of thoracoabdominal space
Which arteries are larger to meet the specialized demands of the avian bodies
Pectoral and brachial
Which blood vessels have been specialized to meet the demands of the avian body?
Renal portal system
What is the renal portal system in birds?
vry important when giving injections in leg
may pass thru portal system first and much of drug eliminated b4 it can affect body
also applies to lizards
What is different about blood flow in birds?
faster HR and more rapid blood flow bc of relatively fast metaolism
Where are electrodes placed on a bird for electrocardiograms?
Electrodes placed on wings and legs detect changes in electrical voltage as heart chambers contract and relax
What are the functions of avian blood
carry nutrients, O2, hormones to cells
Carry metabolic wastes to lungs and kidneys
control and prevent dz, regular body temp
What blood cells do birds have
Birds do not have platelets but they do have erythrocytes, leukocytes (heterophils, eosinophils, basophils, monocytes, lymphocytes and thrombocytes)
What do erythrocytes look like in avians?
oval, nucleated, and larger than those of mammals
formed in bone marrow of adult birds, or in spleen and liver depending on species
posses hemoglobin
total number of cells dependent on age, seg, diet and time of year
What are heterophils in bird cells?
phagocytes
equivalent to mammalian neutrophil
rought with rod-shaped red-orange granules
bilobed nucleus with clumped chromatin
What are thrombocytes in avian blood cells
nucleated cells that act as platelets
smaller than RBC’s with large, round-oval nucleus
Prod by bone marrow in adult birds