Nutrition in Zoos

Question 1

What role did nutrition play 30 years ago in zoos?

Answer 1

25% of captive zoos animals died because of inadequate nutrition

the knowledge about animals diets were limited

improving and understanding nutrition of captive animals is paramount to their continued survival

Question 2

Is the diets in zoo identical to what is in the wild?

Answer 2

No

Question 3

What are the constituents of food that we need to apply to animal food to have a well-balance diet?

Answer 3

1. carbohydrates
2. lipids
3. proteins
   4.fibre
4. viamines
5. Minerals
6. water

Question 4

What is the importants of carbohydrates?

Answer 4

Act primarily as a n immediate energy source during cellular metabolism but if they are present in excess, they are stored in cells as glycogen

Question 5

What is the primary energy source for animals?

Answer 5

Glucose, absorbed from digestion of starch into maltose, then into glucose by enzymes

Question 6

What are lipids and the purpose?

Answer 6

fats, cholesterols, and phospholipids

Type of fat is determined by fatty acids

fats are stored as adipose tissue, act as long term energy reserves and insulation.

omega 6 (bad) and omega 3 (linolenic acid - good)

Question 7

Can animals produce all the fatty acids they need?

Answer 7

No, Animals synthesis majority of the fatty acids they need, some essential fatty acids cannot be produced for themselves and must be present in the diet

Question 8

What are proteins?

Answer 8

Constructed from the DNA contained in the chromosomes, they are have variety of functions;

1. enzymes and control the metabolic activity
2. hormones or antibodies
3. form most structural components in cells - collagen for strengthening skin, actin,myosin, and muscle

Question 9

What are vitamins?

Answer 9

are organic molecules - essential in the diet
function in enzymes regulation, or act as hormones. Essential for growth, health and reproduction

Lipid Soluble vitamins (A,D,E and K) can be stored in the body fat and used for periods of dietary inadequacy

Water soluble vitamins must be ingested frequently - passes through urine as they cannot be stored

Question 10

What happens if an animals consumed too much Vitamins A, D, E and K?

Answer 10

They are lipid soluble vitamins, excess amount of these vitamins may be harmful as they store in the body thus accumating

Question 11

Why do captive animals have vitamin deficiencies?

Answer 11

because their diet is very restricted or because the naturally occurring vitamins have been destroyed by food preparation techniques

Question 12

What animals required/need vitamines C? and why is it important?

Answer 12

Ascorbic acid

bat and anthropoid primates, amphibians, reptiles and many birds and mammals can synthesis it

important for metabolic reactions and in the synthesis of collagen in cartilage

symptoms - joint pain, dry skin, digestive disorders, dry hairs

Question 13

what are signs of vitamin B deficiency?

Answer 13

CNS problems, resulting in convulsions and lack of coordination, diarrhoea, anaemia and impaired growth

Question 14

What is Vitamin B1deficiency?

Answer 14

Lack of vitamin B1 is rare but occurs in pinnipeds that consume raw fish, they contain enzymes that will destroy thiamine

a sudden loss in righting reflex in saltwater crocodiles hatchlings

Question 15

What types of minerals are there?

Answer 15

Macro, micro, and ultratrace minerals

Iron, silicon, calcium

vertebrates need calcium for their skeletons and birds for their egg shell production

reptiles - adequate exposure to UV light in order to promote the absorption of calcium and the synthesis of vitamin D

Question 16

What is the importance of energy in animals and is it a nutrient?

Answer 16

not a nutrient but derived from nutrients
chemical energy is found in the nutrients, and functions of the body including maintenance, growth and reproduction and lactation.

Question 17

how is energy supplied to animals?

Answer 17

energy for activity , growth, and reproduction

Question 18

Do endotherms or ectotherms require more energy?

Answer 18

endotherms (mammals and birds) need more energy per unit of mass than ectotherms to maintain a constant body temperature

Question 19

What is secondary production?

Answer 19

the rate at which animals in a food chain accumulate dry mass (biomass) or energy within the mass/growth of unit area, per unit time

the way the food is ingested - food goes through -
1. cell respiration = heat loss
2. secondary production = growth
3. excretion (urine) = faeces are released

utilisation energy is different depending what environment the animals is in -

Question 20

What is the impact of moving a tropical mammal or endotherms animal to different environment?

Answer 20

Energetic cost of maintaining a constant body temperature are large

Tropical mammals kept outside in zoos in temperate regions may need additional food in order to cope with the energetic demands of heat loss.

Endotherms have high respiration rates and must keep their body temperatures high. This makes them poor converters of food into biomass compared with ectotherms.

Question 21

What is the issue that arises to sedentary animals?

Answer 21

Sedentary animals need less
energy from their food than
active animals or they put on
weight

Obesity is a problem in some
zoo animals because they do
not need to expend energy
searching for food; for
example, some zoo elephants
are considered to be obese
compared with their wild
counterparts (Harris et al.,
2008)

Question 22

What is gross assimilation efficiency?

Answer 22

is a measure of how well an animal utilises it food
Assimilation efficiency (%) = (Food ingested/ faeces egested) × 100

Question 23

What’s the difference between the gross assimilation efficiency of carnivores vs herbivores? and how do elephants differ?

Answer 23

Carnivores - high protein, easily digested and absorbed diets - assimilate > 80% of dietary energy

Herbivores - very inefficient guts and must eat a great deal of food to compensate for this Diets contain large amounts of cellulose from plant cell walls – symbiotic relationship with gut microbiota aids digestion and metabolism = assimilate < 40% of dietary energy

Elephants are not ruminants and their guts are much less efficient. African elephants (Loxodonta africana) have a GAE of approximately 22% (Rees, 1982a). In other words, about 78% of what they eat passes out as faeces

Question 24

What is browse eating? and an example of an animal

Answer 24

Refers to the vegetation provided for browsing
animals:

Branches containing leafy material
Acts as an enrichment, especially if it is
located at the level at which it would normally
occur in the wild, eg. suspended at height for
giraffes.

Many browsers will spend a great deal of time
obtaining food from branches, even when
other food, such as hay, is provided at the
same time.

Elephants will spend hours using their toe
nails to break small pieces of bark from tree
trunks provided as food and enrichment.

Question 25

What is the difference between grass vs browsers?

Answer 25

Main difference - whats in it Grasses type - monocots cell wall - thick high cellulose/hemicellulose plant defence compounds - silica Broweses type - herbaceous and woody dicots (forbs, shrub leaves and stems) Phenolics – tannins Terpenes Alkaloids

Question 26

What are the anatomical differences between grazers and browers?

Answer 26

Grazers * Larger, more muscular, subdivided rumen/reticulum * Smaller opening between reticulum and omasum Browsers * Narrow muzzles * More mobile lips and tongues - wrap around and grab leaves * Larger salivary gland - combat antinutritional factors - deactivate antinutritional enzymes * Smaller rumen * Large abomasum and hindgut (cecum and colon)

Question 27

How do relative size of organs differ with diets of birds?

Answer 27

the more grass the longer the digestive tract is Carnivorous - small crop and caeca, simple digestive tract Omnivorous - Herbivorous expanded foregut - large microbial fermentations long midgut Large colon

Question 28

How is the Mongastric Hindgut fermenters (herbivores) digestive tract designed to assist them in their diet?

Answer 28

Mongastric Hindgut fermenters (herbivores) Enlarged hindgut, preceded by a simple - stomach and intestine Maximises utilisation of fibre rich diets

Question 29

How are koala's digestive tract adapted for eating eucalyptus?

Answer 29

Monogastric hind gut fermenter Enlarged caecum (2 m in length) and colon Diet of eucalyptus leaves (~200-250 g of leaves / day) - Mature leaves are highly fibrous - consume immature leaves - High tannin and volatile oil content, toxic to other animals Very slow metabolic rate → long retention time to maximise amount of energy extracted - Solutes and fine feed particles are retained in the caecum/proximal colon for ~200 hours - Large particles are retained for < 20 hours - Only absorbs 25% of ingested fibre Water is absorbed from leaves – low requirement to drink

Question 30

How is a kangaroo specialised in its digestive tract?

Answer 30

Monogastric – foregut fermenters BUT it has TWO enlarged pre-gastric chambers: 1) Sacciform - sacklike front chamber contains an abundance of bacteria, fungi and protozoa that begin the fermentation process. Food may remain here for many hours until fermentation begins 2) Tubiform – after fermentation begins food passes into the second stomach chamber, where acids and enzymes finish digestion.

Question 31

What is the difference between foregut and hindgut fermentation?

Answer 31

Foregut fermentation prior to enzymatic digestion and absorption: use of bacterial protein, bacterial products (b-vitamins) Bacterial detoxification loss of easily digestible substrates and bacterial modification Hindgut fermentation (orangutan) fermentation after enzymatic digestion and absorption loss of bacterial protein bacterial productions (b-vitamins?) (coprophagy can be retain nutrients - regaining some protein) Use of easily digestible substrates - sugars, proteins use them more efficiently

Question 32

What is the intake and passage rate in hindgut and foregut animals such as primates?

Answer 32

Intake and passage rate in primates - dictates how time the digestive tract has to absorb nutrients from feed. high or low intake hindgut fermenters can either have high or low intake and short or longs ingesta retention nonruminant - limited to a low food intake and hence long ingesta retention SEE LECTURE SLIDES

Question 33

What is the compared effects of feeding high-sugar/starch diets in colobus monkey and orangutan?

Answer 33

Foregut - easily digestible - nutrients enters the fermentation chamber = malfermentation low food intake laminitis, liver abscess, reduced lifespan, diarrhoea, orial stereotypies = thin/skinny monkey Hindgut -easily digestible nutrients absorbed in small intestine which can lead to obesity only excessive amount can lead to caecum acidosis, diarrhoea, laminitis = obese

Question 34

What is the minimum required supplement for carnivores and why?

Answer 34

* A supplement containing at a minimum calcium, vitamin A, iodine, taurine, and some B vitamins should be added to the meat diet. * reduces incidence of nutritional problems in captive exotic carnivores; however, such a diet regularly causes fecal problems

Question 35

How to exotic felines diet differ?

Answer 35

* Exotic feline diets are usually higher than canine diets in fat, protein, and vitamin A.

Question 36

Why do zoos use frozen and canned cat foods?

Answer 36

* Frozen and canned cat foods usually are more palatable than dry ones to exotic cats. * Many zoos prefer to use frozen diets over canned products, because generally they are less expensive and large quantities are easier to feed.

Question 37

What is the issue with soft-hamburger consistency of commercial diets? and what is recommended for those who do recieve this diet?

Answer 37

can result in excess calculus deposits and periodontal disease if hard or unprocessed items are not also provided. * All cats fed a soft diet should receive bones with some meat intact twice weekly.

Question 38

What was the traditional approach to zoo nutrition? and what are the benefits vs negatives to this.

Answer 38

"Do as we always did" based on experience of what is been working - this means mistakes have been made for a long time "imitate the natural diet" best approach - depends on what we know about the natural diet Two ways to approach this 1. Ratcliffe and wackernagel - a complete feed for each animal (group) Pelleted/extruded - atypical physical structure. But some nutrients are difficult to limit and behaviour deficits (obtaining the food) 2. Hediger ‘natural’ feeds (forages, fruits/ vegetables), that resemble the natural diet Selective feeding possible Available feeds differ in nutrient content from the natural diet "use a suitable domestic species as a model" scientific compromise - huge amount of knowledge exists but species-specific peculiarities are easily overlooked. "Based on studies in zoo animals" Scientific approach - financially and logistically challenging, difficulty in summarizing knowledge

Question 39

What are nutritional problems faced in zoos with carnivores, primates, Fish-eater, and herbivore?

Answer 39

carnivore - red meat = calcium deficiency primate - fruit and veggies = calcium deficiency fish-eater - thawed fish = sodium and vitamin B deficiency Herbivore - hay and grains = acidosis, vitamin E- and calcium deficiency

Question 40

Wild VS ZOO

Answer 40

LOOK AT SLIDES

Question 41

What is the issue with researching in a zoo setting? and how are issues prevented

Answer 41

Studies only allowed if of no risk to the zoo animals ‘Risk-free’ options for nutritional studies include: - Inventories - Epidemiological studies - Measuring digestibility - Measuring digesta passage on used diets

Question 42

What do you do with novel species or those new to captivity?

Answer 42

1. Identify species feeding strategy and nutritional ecology *Determine if herbivore, carnivore or omnivore * Is the animal a browsing herbivore, selective insectivore etc. 2. Gastrointestinal tract morphology * Including anatomy of oral cavity (why?) - indication into how and what it eats, leafs, trees, etc 3. Known and/or extrapolated species requirements * Model from data for domesticated species with similar GIT and feeding strategies * Consider energy requirements of domestic animals are often based on performance criteria (growth, lactation etc.) which may not apply to zoo animals. 4. Foods available and their cost * Foods available in the wild are not always available in captivity – use harvested forages, fruit and vegetables, meat and dairy products. * Choices should be made on the basis of nutrients foods bring to the total diet, not an attempt to substitute what one perceives to be analogous food ‘types’