Small Mammal GIT Flashcards
1
Q
What are lagomorphs?
A
- rabbits
2
Q
What are hystricomorphs?
A
- guinea pigs
- chinchillas
- degus
3
Q
What are myomorphs?
A
- mice
- rats
- hamsters
- gerbils
4
Q
What are scuiromorphs?
A
- chipmunks
- prairie dogs
5
Q
What are mustelids?
A
- ferrets
6
Q
What type of feeder are lagomorphs and hystricomorphs?
A
- herbivores
7
Q
What type of feeder are myomorphs and scuiromorphs?
A
- omnivores
8
Q
What type of feeder are mustelids?
A
- carnivores
9
Q
What is a herbivores mouth design?
A
- designed for chewing
- narrow gape (cant open mouth that wide)
10
Q
What is a carnivores mouth design?
A
- designed for grasping/tearing
- wide gape
11
Q
What does omnivore mouth design depend on?
A
- diet
12
Q
What is the dental formula for rabbits
A
- I 2/1
- C 0/0
- P 3/2
- M 3/3
13
Q
What are rabbits premolars and molars called?
A
- cheek teeth
14
Q
What teeth in a rabbit continuously grow? and what is this called?
A
- incisors and cheek teeth
- diphyodont
15
Q
Rabbits have two sets of upper incisors - What are the ones behind called?
A
- peg teeth
16
Q
In rabbits enamel coverage is different between incisors and peg teeth - how?
A
- incisors have enamel on the outside only
- peg teeth have enamel all the way round
17
Q
How much do rabbit teeth grow a week?
A
- Grow 2mm a week
18
Q
What do normal cheek teeth have in a rabbit?
A
- should have spur in lingual side but not hooks and should be uniform and vertical
19
Q
What dental problems do rabbits have?
A
- Dental overgrowths secondary to inappropriate diet = abnormal spurs
- congenital malocclusion
- traumatic injury
- dental abscess
- ulceration of tongue
20
Q
How can you look at rabbits teeth?
A
- by giving them a full anaesthetic (safer than sedation)
21
Q
What can you do to prevent over growth of rabbit incisors?
A
- bur them
22
Q
What is the dental formula for hystricomorphs?
A
- incisors 1/1
- canines 0/0
- premolars 1/1
- molars 3/3
23
Q
How do teeth grow in hystricomorphs?
A
- All teeth constantly growing
24
Q
How do teeth grow in myomorphs?
A
- incisors are the only constantly growing teeth
25
What is dental formula for myomorphs?
- incisors 1/1
- canines 0/0
- premolars 0/0
- molars 3/3
26
How do teeth grow in scuriomorphs?
- incisors are the only constantly growing teeth
27
What is the dental formula for scuriomorphs?
- incisors 1/1
- canines 0/0
- premolars 0/0
- molars 3/3
28
What issues can hystricomorphs have with their teeth?
- misaligned incisors
29
What issues can myomorphs have with their teeth?
- crossing over incisors
30
If there are issues with incisors what does this usually stem from?
- issues with cheek teeth and improper grinding
31
You can remove incisors in the rabbit - what do you need to do in order to do this?
- need to remove germ cells at root of tooth to prevent re-growth
32
Why is it difficult to remove incisors in the rat?
- not easy to remove incisors in the rat as they sit within the nasal cavity and sinuses and can damage structurers easily
33
What is the normal dentition of a ferret?
- deciduous initially
- permanent from 7 weeks of age
- strong muscles of mastication allowing clamping onto pray
34
What can ferrets have wrong with their dentition?
- dental disease like other carnivores
35
How is food broken down in the hindgut fermenter?
- food is broken down by microorganisms in the caecum
36
Small herbivores have a fast transit time - why?
- fast metabolism
- very light delicate bones so cannot have too much food as they need to move quickly as prey species
37
How do small herbivores gain maximal nutritional value?
- food needs to be processed twice = caecotrophy
38
Why can't rabbits and rodents vomit?
- due to structure of oesophagus entering stomach
39
What do rabbits need in their diet in order to grind their teeth?
- good quality forage and roughage
40
Where is the stomach located in the rabbit?
- cranial abdomen on the left side
41
Describe the structure of the rabbits stomach:
- large and thin walled
- well developed cardiac sphincter
42
Describe the small intestine the the rabbit:
- relatively short, location of the majority of CHO and protein digestion
- duodenum, jejunum and ileum
43
What is the sacculus rotundus in the rabbit (unique to them)?
- dilation at the terminal ileum, at the iloecaecacolic junction composed primarily of lymphoid tissues
44
In the rabbit what is the proximal and distal colon separated by and what does it do?
- Fusus coli
- separates the high fibre particles from low fibre particles
- specially adapted area of colon which acts as a differential pacemaker for gut motility
45
What happens to indigestible fibre in the rabbit?
- passes into the distal colon to be passed as dry faecal pellets
46
What happens to digestible fibre in the rabbit?
- passes into caecum to undergo fermentation producing VFA
47
What does the caecum do in rabbits?
- contains mixture if microorganism which are involved in the fermentation of the digestible fibre into VFA (mainly aetate) which is absorbed directly
48
What is the principal species of microorganism in rabbits?
- bacteroides spp
49
What other species of microorganism can be found in the rabbit?
- E.coli
- Clostridia
- ciliated protozoa
- yeast (saccharomyces)
50
Rabbits produce what 2 types of droppings?
- faecal pellets (about 150/day)
- caecotrophs usually passed 4-8 hours post feeding, usually at night
51
What is the appearance of caecotrophs?
- smaller, soft shiny appearance due to mucus coating
52
How are caecotrophs digested?
- swallowed whole directly from anus
- digested in the intestines to provide microbial protein, Vit B and K and fatty acids
53
What reasons can lead to hypomotility (gut stasis)?
- poor quality/low quantity fibre diet
- pain (rabbits are sensitive to pain and tend to hide it)
- stress
- systemic disease
- GI obstruction
- Gut stasis is a clinical sign not a diagnosis
54
hypermotility is rare - what can cause it?
- intestinal flora problems (can be due to antibiotics)
- obesity/arthritis - anything that makes movement to perform caecotrophy hard
55
Where is the caecum in a guinea pig?
- have a large caecum on the left
56
What digestive issues can hystricomorphs suffer from?
- anorexia
- gut stasis
- intestinal flora imbalance
- diarrhoea ( particularly in chinchillas fed fruit and beg based diet)
57
Why are guinea pigs more likely to have diarrhoea?
- due to fruit passing quickly through digestive system and needed this to meet their vitamin C requirement
58
Describe myomorph digestion:
- omnivores much simpler digestive tract
- varies with diet
- hamsters have a fairly well developed caecum
59
What type of GI tract do ferrets have?
- simple digestive tract
60
What is the GI transit time for ferrets?
- 3-4 hours
61
Why do ferrets need to eat frequently?
- otherwise hypoglycaemia a concern
- they are not starved before a surgery
62
What are intestinal trichobezoars?
- mat of hair has been ingested
63
How does hair normally pass through the system?
- normally passed through and excreted within the faecal pellets
64
When does ingested hair become a problem?
- problems occur when excessive amounts if hair are ingested or hair within the intestines dehydrate and from hard structures which can lead to obstruction
