Nutrition of Fish Birds and Reptiles

Question 1

What are the implications for fish feed depending on the type of fish?

Answer 1

Need to make different diets depending on the type of fish you are feeding. i.e. top, middle or bottom feeders. Therefore food that either floats or sinks. Also night or day feeding.

Question 2

Fish are very rich in ____ that make a big difference in human health. How are they rich in this?

Answer 2

Omega 3 fatty acids. Through the food chain. Fish eat algae which are high in omega 3 then we eat fish

Question 3

Do fish have teeth? What implication does this pose for food ingestion?

Answer 3

Only few species have teeth, instead they have a boney mouth to grasp food. Food is then eaten as whole or large particles

Question 4

How does stomach size of fish relate to meal sizes?

Answer 4

Fish have small stomachs therefore need smaller meal sizes and possibly multiple meals per day.

Question 5

What happens to food in small fish with no stomach?

Answer 5

Food passes directly into intestine so food must be swallow size. If too big it might be able to get into mouth but could get stuck. Want small enough to immediately go into SI

Question 6

Ectothermic fish have special energy requirements based on body temp. Explain this

Answer 6

Ectothermic fish do not maintain a constant body temp (“cold blooded”) therefore body temp fluctuates with water temp. There is a direct relationship between metabolism and water temp so if temp goes up energy metabolism is up regulated (more energy being used). Temp goes down, energy metabolism is down regulated (reduce metabolism)

Question 7

What is a survival benefit of fish related to energy?

Answer 7

Need less energy to maintain normal life.

Question 8

Do fish rely more on amino acids are carbohydrates for nutrients?

Answer 8

Amino acids

Question 9

What is unique about protein turnover in fish

Answer 9

They have a higher protein turnover than mammals and they require more protein than most mammals.

Question 10

Can fish utilize starch?

Answer 10

Omnivorous and carnivorous fish can utilize starch but it’s better if it’s gelatinized (cooked).

Question 11

What are the implications for making a fish food if they require a high protein diet?

Answer 11

Fish food must be maid of protein which is likely coming from big ingredients like fish meal… Fish that have been processed into fish food.

Question 12

What is a sustainability issue regarding fish food? How would you fix this?

Answer 12

Having to use fish to feed fish… Fix by not using fish meal in fish feed us other protein sources from pulses instead.

Question 13

How do you make fish food?

Answer 13

Extrusion. Very advanced. Need to contain some starch and protein on plant based origin and try to make this as digestible as possible. Try to make it less based on animal protein.

Question 14

Why do fish need a regular Calcium supply?

Answer 14

Because they don’t have hard bones therefore they have no source for calcium in periods of deficit.

Question 15

How do you provide water soluble vitamins to fish?

Answer 15

Over supplement water soluble vitamins in the hope that the food gets eaten before water soluble vitamins disappear.

Question 16

What vitamin is essential to fish because they can’t synthesize it?

Answer 16

Vitamin C

Question 17

What does Vitamin C deficiency lead to?

Answer 17

Lordosis= upward and downward curvature of spine.

Question 18

What is the relationship between nutrition and fish colour?

Answer 18

Nutrition plays a key role in allowing fish to exhibit their colour.

Question 19

Why is omega 3 and omega 6 fatty acids needed in fish?

Answer 19

Due to change in water temp. Linolenic acid (omega 3) is needed to keep fish membranes fluid even when temp is cool.
• When water temperature goes up you need less omega 3.

Question 20

What is the difference between chicken and companion animal bird digestive tracts?

Answer 20

Chickens can’t fly where as ornamental birds can. Therefore ornamental birds have smaller digestive tract because don’t want to be carrying around a lot in their stomach when trying to fly.

Question 21

Can birds use fibre?

Answer 21

Many cannot. They eat more protein, starch and fat to make up nutrient requirements. Some birds don’t have cecum or colon therefore no bacteria to ferment fibre and it just gets excreted out. For this reason not many fresh food and vegetables should be fed as they are a poor source of protein.

Question 22

What are 3 ingredients to be mixed together in bird feed and why?

Answer 22

Cereal grain because it’s rich in starch. Pulses as it is a blend of starch and protein and oil seeds as they are a blend of oil and protein. Mix these and get an array of nutrient packages still in original seed form.

Question 23

Why does feather growth require a large amount of amino acids and what are these amino acids?

Answer 23

• Need large amounts of amino acids for feather growth.
• Proline, glycine, methionine and cysteine are needed.
• Methionine and cysteine both contain sulfur which is important for disulfide bonds to form for feather growth
• Disulfide bonds provide rigidity

Question 24

What is unique about uric acid synthesis in regards to energy in birds compared to other animals?

Answer 24

Uric acid synthesis takes more energy to make than urea therefore it increases the energy requirements of the animal. Other animals make urea which is less energy expensive.

Question 25

What is an essential amino acid for growing and reproducing birds?

Answer 25

Glycine

Question 26

What is moult and what are it’s implications for amino acid requirements?

Answer 26

Moult is replacement of feathers with new feathers. Large amounts of well-balanced amino acids especially methionine, cysteine, proline and glycine are needed.
Overall birds have an increased protein and energy requirement during moult.

Question 27

How is herbivorous reptilian digestive system different from mammals?

Answer 27

There are numerous folds. (probably to slow down passage through digestive tract therefore increasing time for bacteria and protozoa to ferment food)

Question 28

Are herbivorous or carnivorous reptiles larger? And why?

Answer 28

Herbivorous because a larger body size and digestive tract will allow for more vegetative matter to be consumed.

Question 29

What may be caused by dehydration in reptiles?

Answer 29

Gout or excess drying of skin and inability to shed.

Question 30

How does temperature of reptiles relate to food intake and metabolism?

Answer 30

They are ectothermic. Therefore too low temperature will result in a decrease in food intake (therefore nutrient requirements and growth). Too high temperature will cause excessive metabolism of nutrients and decreased food intake and growth.