Lecture 10b: Nutrition Science Flashcards
1
Q
What does nutrition science include
A
- diet production
- clinical case
- nutritional welfare
- research
2
Q
Two types of nutrition science research
A
- conservation based
- well-being based
3
Q
Vancouver Island Marmots
A
- endemic to Vancouver
- major population changes since the 70s
- not a self-sustaining population
- On the brink of extinction
4
Q
Challenges of survival for the Marmots
A
- forestry: intensive logging practices
- predators: altered landscape increase access to predators
- late maturing: 3-4 years old
- frequency of reproduction: reproduce every other year to 3-4 pups
5
Q
Survival of marmots
A
- low yearly survival rate
- captive bred and released marmots. have a higher risk of mortality
- issues relate to the first hibernation
6
Q
Gaps in our knowledge about marmots
A
- body composition
- wild type diet (1 publication)
- captive diet (does it match)
7
Q
Hibernation physiology and diet fatty acid
A
- hibernators drop core body temperature, they have the physiology to do that
- mortality of non-hibernators is from heart failure which is caused by increased cytosolic CA2+
- hibernators maintain Ca2+ influx and release through SERCA proteins
- these proteins are influenced by the presence and ratio of PUFA in the sarcoplasmic reticulum
8
Q
What is their hypothesis for marmots in captivity?
A
Lipid metabolism and hibernation of Vancouver Island Marmots are affected by captivity
9
Q
VIM in captivity
A
- increased body condition
- cardiovascular disease
- shortened hibernation
- first wild hibernation survival
- hibernation and breeding success
10
Q
Fatty Acid Profiles
A
- looked at their fatty acid profiles
- what does their fat and blood look like in the context of fatty acids since fatty acids impact their ability to hibernate
11
Q
Fatty acid profiles of VIM in captivity
A
- had higher fatty acids in their blood
- high ratio of N6:N3
- increased short fatty acid chains
- elevated palmitoleic acid and cis-vaccenic acid
12
Q
Fatty acid profiles of VIM in the wild
A
- had long fatty acid chains
- high HUFA score = good CV health
13
Q
Data for developing research pellet
A
- coalescing data from comparative species (plant preferences, stomach contents, WAT & organs)
- hibernation studies
- season changes in FA profiles
14
Q
Research pellet
A
n6:n3 ratio ~ 1.0
old one was 5.0, 5 n6 for every 1 n3
15
Q
Diet study for the VIM
A
- used woodchucks
- treatment group: start on high n3 diet and then swithc to high n6 late in summer
- control group: high n6 diet entire study
- determine if we could alter their hibernation and could we alter their health outcomes
16
Q
woodchuck results from the diet study
A
- assessed: diet intake, body weight, body composition, body temperature, fatty acid profiles
- failed hibernation
- but, more favourable FA profile
- one the road to improve their health, maybe not hibernation yet
17
Q
Conservation impacts on VIM
A
- improve diet in captivity
- captive vs wild (continue to study - missed?)
- fatty acid “targets”
- more resilient captive populations
18
Q
when are polar bears the fattest?
A
may/june
19
Q
Polar bear behaviour and physiology
A
- climate change impacts survival
- shrinking sea ice:
> ~30 days less to feed
> longer fasting period
> less fat deposits - study current ecological adaptations (adaptability to look for other food sources other than seals)
20
Q
Polar Bear Adaptations
A
- body mass changes: 50% increase in bodyweight during anabolic period
- ice free period: decrease energy outputs
- female denning period
21
Q
Benefits of polar bear research in a zoo setting
A
- controlled environment
- 365/24/7 data
- various life stages, ages, and health conditions
- individual bear can be tracked over years
22
Q
Toronto zoo feeding strategy
A
- the toronto zoo developed a seasonal breeding program
- goal is to mimic calorie supply/flow
23
Q
what does the toronto zoo feeding strategy measure?
A
- body condition
- body mass changes
- speed of weight loss
- % body fat
- behaviour
- blood values
24
Q
Polar bear data collection
A
- daily diet intake
- weekly: behaviour, bodyweights
- monthly: body temperature, blood draws
25
How fat is a polar bear?
use SLBL (straight length body length) to measure structural mass
26
body composition model
- more accurate
- there is a difference between structural and storage mass
- validations of SLBL and body mass calculations using Bio-electric impedance
27
bio-electric impedence
- put a small current through the polar bear
- measure how long it takes for the current to pass through
- moves through water
- this tells us how much water
- the inverse will tell us how much fat
28
cub diet goals
- develop milk formula
- express calorie supply as a function of metabolic body weight
- provide growth data to researchers
29
Western Hudson Bay Bear Cubs
- cubs gain mass from birth until sea ice breakup
- lose body fat until ice returns
- still undergo structural growth during ice free period
30
Toronto Zoo bear cubs
- cubs gain mass continuously - didn't think it was appropriate to make them lost fat in their first year
- housed solo
31
Results and Impacts with the polar bears
- body weights were comparable to wild averages of ice break (June)
- average daily gains differed
- average ME approached 4 X BMR
- impact - better understanding of how to feed cubs
32
Polar bear - conservation impact
- estimate calorie requirements for survival, reproduction, growth of cubs
- better understand behavioural and physiological changes
- validation of techniques used in the field
- determine what information do researchers actually need (energy budget models)
33
Nutritional animal well-being research
research on the Masai giraffe
- measuring microbiome changes of Saliva and Cud during rumination events
34
Rumen
multi chamber stomach where a lot of fermentation occurs
35
Giraffe and rumen health
- if we feed them the wrong diet (improper fibre), the microbiome changes
- they are not evolved to eat certain foods so their outputs change the rumen
- go through rumenal acidosis (very acidic state) which will erode the surface of the rumen
- cannot absorb nutrients anymore
36
Taking sample from the zoo
- take a swab of their mouth during rumination
- bolus from sloppy eating giraffe
37
Potential outcomes from microbe research
- validation of domestic technique in wildlife
- determine if browse can influence microbe
- first ever glimpse at giraffe microbiome
