A30 - The respiratory and the urogenital system of the domestic birds

Question 1

Respiratory system

Nasal cavity

Answer 1

• Nasal openings on both sides of the skull
• ​Separated by septum
• Nasal cavity is composed of:
  
  • ​Premaxilla
  • Maxilla
  • Os nasale
  • Vomer
  • Os palatine
  • (Os jugulare)
  • 3 choanae
    
    • ​Cranial (sometimes absent)
    • Medial (largest)
    • Caudal
• Ø sinuses
  
  • Sinus maxillaris: recessus in maxilla
  • 2 “sinuses” connect to caudal choanae

Question 2

Respiratory system

Larynx

Answer 2

• 2 larynx:
  
  • 1 proximal (separates food and air)
  • 1 caudal
• Ø epiglottis
• Ø cart. thyroidea
• Cart. cricoides (does not close, unpaired)
• Procricoid? (completes ring, unpaired)
• Cart. arythnoidea (layers of muscles control opening and closing of larynx, paired)
• Trachea have completely closed rings
• Syrinx: distally, at bifurcation of trachea, s​ound production
  
  • Pessulus: separates bronchial opening

Question 3

Respiratory system

Lungs

Answer 3

• Between 3^rd rib → 6^th rib
• Bronchi
• Secondary bronchi
• Parabronchus
  
  • ​Tubes surrounded by vessels for gas exchange
  • Connect to neighboring parabronchi

Air sacs:

• 9 air sacs:
  
  • Crainal group (used air)
    
    • ​2 Cervical sac
    • 1 Clavicular sac
    • 2 Cranial thoracic sac
  • Caudal group (fresh air)
    
    • 2 ​Abdominal sac
    • 2 Thoracic caudal sac
• Always open from saccobronchii
• Very thin walls
• In touch with every organ (ø brain)
• Ø diaphragm

Question 4

Urogenital system

Urinary system

Answer 4

Kidney:

• Location: fossa renalis of synsacrum​
• In contact with lungs
• Abdominal air sacs lie ventrally
• Division by a. iliaca externa:
  
  • Cranial division
  • Medial division
  • Caudal division
• Ø pelvis renalis
• Cortex renalis and medulla renalis are not clearly demarcated
• Bloo vessels of the kidney:
  
  • A. renalis cranialis/medialis/caudalis
    
    • ​A. renalis cranialis ex aorta
    • A. renalis ventralis ex a. ishiadica
  • ​ V. portae renalis recive blood from caudal part of the body
  • Portal valve regulates the amount of blood entering the kidney

Ureter:

• Arises from cranial division
• Travels caudally with genital duct
• Opens in urodeum

Ø bladder

Ø urethra

Question 5

Urogenital system

Male genital system

Answer 5

• 2 testis
  
  • Internal organ:
    
    • ​​Within the abdominal cavity over cranial division of kidney
    • Surrounded by abdominal air sac for cooling
  • Leads to ductus deferens
  • Left one is bigger
  • Enlarged during reproductive phase
• Epididymis
  
  • ​Internal organ
• Ductus deferns
  
  • Internal organ
  • Connected to the testis
  • ​Sends the sperm to a small papilla in the cloaca
• Phallus
  
  • ​External organ
  • 2 papilla, coming together from each side
  • Copulatory organ
• Ø accessory reproductive gland

Figure: phallus

Question 6

​Urogenital system

Female genital system

Answer 6

• Enlarges during reproductive stage
• Ø uteru
  
  • ​Tuba uterina opens into cloaca
• Division of tuba uterina:
  
  • ​Infundibulum (25-30 minutes)
    
    • ​Site of fertilization
    • Can store sperm in special folds
  • Magnum (3 hours)
    
    • ​Longest part of oviduct
    • Egg-shell production
  • Isthmus​ (1-2 hours)
  • “Uterus” (19-20 hours)
  • Cervix
  • Vagina / uterovaginal sphincter (1 minute)
    
    • ​Opens into urodeum