Ruminant head Flashcards
The horns of a ruminant are closer to the eye in what kind of ruminant?
Small ruminants
Do ruminants have facial crest?
No but have a facial tuberosity at M1
Where is the infraorbital foramen in the ruminant?
Dorsal to the first cheek tooth
Do ruminants have a nasoincisive notch?
Yes
What is the foramen orbitorotundum?
Combination of the orbital fissure and round foramen
What bone projects over the foramen in the orbit and blocks them laterally?
Pterygoid foramen
Where is the foramen orbitorotundum?
Ventral to the optic canal
What window can you use to get to the foramina in the orbit?
Between the zygomatic process of the frontal bone and the coronoid process of the mandible and the zygomatic arch
What is the lacrimal bulla?
Extension of the maxillary sinus that sticks into the orbit
Why is the lacrimal bulla important?
When doing an enucleation you could break this and contaminate the surgery site
What is different about the coronoid process of the mandible in the ruminant?
Ventral to the temporal line which is more lateral and it is thinner and more sloping caudally
What is the lacrimal fossa?
Unique to the sheep and is where the cutaneous gland sits
Do ruminants have canines?
Technically yeah but they pretty much look incisors
What type of tooth are ruminant incisors?
Brachydont
What is the ruminant dental formula?
2(I0/3, C0/1, P 3/3, M 3/3)=32`
What is the deciduous dental formular for ruminants?
2( Di 0/3, Dc 0/1, Dp 3/3)= 20
How many cheek teeth do yearlings have?
5 cheek teeth ( 3 premolars and 2 molars)
How much earlier do permanents erupt in small ruminants?
6 monts
At what age should small ruminants have all their permanent cheek teeth>
2 yrs
When are deciduous teeth present in an ox?
Within 2 weeks. Small ruminant premolars erupt later
Eruption date for ruminant I1?
1.5-2
Eruption date for ruminant I2?
2-2.5
Eruption date for ruminant I3?
3-3.5
Eruption date for ruminant C1?
3.5-4
When do ruminant M1 erupt?
6 mo
When do ruminant M2 erupt?
12-18mo
What is a peg?
Happens around 10-12 years when the incisors are completely worn away
What are the diverticulum of the frontal sinus?
Cornual, postorbital, and nuchal diverticulum
What are the surgical limits of the maxillary sinus?
D: Medial angle of eye tp infraorbital foramen
V: Facial tuberosity to zygomatic arch
R: Just rostral to facial tuberosity
Ca: Ventral margin of bony orbit
Medial part of the maxillary sinus communicates with what?
Palatine sinus
What makes the cows have less lip movement?
Thickened nasolabial plate
