9: Nutrient requirements for adult dogs

Question 1

What is an adult dog

Answer 1

Young to middle-aged dogs
Fully grown (about 12 months)
Not over 5-7 years

Question 2

Goals of adult dog nutritional management

Answer 2

Maximize longevity, quality of life and disease prevention

Question 3

Factors influencing energy requirements of dogs

Answer 3

• Gender and neuter status
• Breed
• Age (growth)
• Reproduction: gestation and lactation
• Activity level (sport/working dogs)
• Environment

Question 4

How does breed affect nutrition?

Answer 4

• different breeds may be at risk for specific diseases or metabolic alterations
• maintenance energy requirement varies with differences in lean body mass, temperament and activity level

Question 5

How does activity level affect energy requirements

Answer 5

• standing requires 40% more energy than lying
• consistently higher level of physical activity increases lean body mass (increased energy use even at rest)

Question 6

Changing feeding practices based on activity level

Answer 6

• activity cannot be defined precisely
• feeding recommendations should initially be conservative
• avoid overfeeding to prevent obesity

Question 7

Environmental factors that affect energy requirement

Answer 7

Temperature, humidity, type of housing, stress level and degree of accclimatization

Question 8

Animal factors that affect tolerance to environmental factors

Answer 8

• Isolative characteristics of skin and coat (subcutaneous fat, hair length and coat density)
• difference in stature, behaviour and activity

Interaction with breed!

Question 9

Heat losses at lower critical temperatures? How does it vary with breed?

Answer 9

Heat losses are minimal (minimum metabolic rate)

• Longhaired breeds = 15 to 20 C
• Shorthaired breeds = 20-25 C
• Arctic breeds = 10 to 15 C

Question 10

Slide 11

Answer 10

Graph

Question 11

Energy needs for body cooling? When?

Answer 11

When ambient temperature higher than dog’s thermoneutral zone
- small increase in E requirement
- drastic increase in water requirement

Question 12

Why are energy requirements of animals with differing weights not directly related to BW

Answer 12

Energy used by the body is also related to total body surface area. Need interspecies mass exponent (0.75 in dogs)

Question 13

Maintenance energy requirement in dogs

Answer 13

130 kcal ME x kg BW^0.75

Question 14

Why is resting fed metabolic rate higher than BMR? By how much? MER = ?(in terms of BMR)

Answer 14

Dietary thermogenesis
Approx 15% higher than BMR in adult dogs

MER = BMR + thermoregulation + regular activity + fed

Question 15

Slide 14

Answer 15

Breeds/activity levels above and below average requirements

Question 16

Dog water requirement

Answer 16

• Body has limited capacity to store water
• water deprivation will result in death
• require a constant of water to replace losses through urine, feces, and respiration

Question 17

Factors affecting voluntary water intake in dogs

Answer 17

• Environmental temperature (panting = loss of water vapour)
• type of diet fed (dry=increase intake)
• dogs activity level
• physiological state (e.g. lactation)
• health
• energy intake (more E = more metabolic waste products e.g. heat from nutrient metabolism, high CP diets)

Question 18

How do dogs adapt water intake based on food?

Answer 18

Dry dog food has 7-12% water, canned food has up to 78% water

Dogs fed canned food have lower voluntary water intake than dogs fed dry food

Question 19

What is metabolic water

Answer 19

Produced during oxidation of energy containing nutrients in body
5-10% of total daily water intake

Question 20

How can we estimate water requirement by measuring energy intake

Answer 20

1 kcal energy = 1 ml of water

Question 21

When is there no benefit to extra dietary protein?

Answer 21

When AA requirements are met
- excess must be deaminated by the liver
- nitrogen-byproduct excreted via kidneys

Question 22

What do adult dogs need protein for

Answer 22

Maintenance and activity

Question 23

Slide 20

Answer 23

Look

Question 24

Nitrogen balance in adult vs growing animals

Answer 24

In adults, N in food minus N in feces and urine should = 0 (appropriate protein intake)

For growing animals, account for weight gain (should have a positive nitrogen balance)

Question 25

Why is apparent ileal digestibility of protein/aa more accurate than apparent total tract digestibility?

Answer 25

Amino acids can only be absorbed in the small intestine, not LI
A lot of microbial affects on protein/aa in LI that cause an error in determining digestibility of aa
SI (ileal-cannulation) most accurate way of determining digestibility of aa

Question 26

Recommended CP allowance for adult maintenance? Why use CP instead of aa requirement?

Answer 26

25 g CP/1,000 kcal ME

CP analysis is cheap, aa analysis is expensive

Question 27

What are the functions of arginine (4)

Answer 27

• key intermediate in urea cycle (detoxification of nitrogenous wastes)
• release of several hormones and metabolic mediators (e.g. insulin, glucagon)
• precursor of biogenic amines
• precursor of neurotransmitters

Question 28

Arginine deficiency in dogs

Answer 28

Dogs consuming a meal without arginine will develop signs of ammonia toxicity
- tremors, vomiting, profuse salivation and hyperglycemia

Question 29

Dog tolerance to fat

Answer 29

• tolerate high amounts of fat in diet (70% of energy in form of fat)
• dogs adapt to wide range of fat types and amounts

Question 30

Considerations when feeding diets high in fat in dogs

Answer 30

• Ensure adequate intake of protein, minerals and vitamins
• adjustment for high energy value

Question 31

What source of fat should we be careful with in dogs?

Answer 31

Tallow (beef fat) is low in linoleic acid (essential fa)

Question 32

Dietary fat digestibility

Answer 32

• apparent digestibility of fat: 70 to 95% (more digestible than protein or CHOs)
• plant sources (oils) more digestible than animal fats

Question 33

Essential f.a. in dogs

Answer 33

• linoleic and a-linolenic acid
• dogs can synthesize sufficient arachidonic acid from linoleic acid
• dietary long-chain PUFA (EPA and DHA) can help prevent skin disease

Question 34

Low amounts of fat in diet lead to…

Answer 34

• deficiencies in total energy
• essential f.a. deficiency = hair loss, development of a dry, dull coat and skin lesions and infections
• decreased food palatability

Question 35

Consequences of overfeeding fat

Answer 35

• diarrhea
• weight gain and obesity (high palatability of energy dense diet)

Question 36

Linoleic acid:a-linolenic acid ideal ratio in dogs

Answer 36

26:2.6 (more linoleic acid needed)

Question 37

Why don’t dogs have an absolute dietary requirement for CHOs? Instead they have…

Answer 37

Dogs have multiple mechanisms to maintain blood glucose
Can convert excess aa, fat, fiber into glucose

They have a requirement for glucose and glucose precursors (from lipolysis and gluconeogenesis)

Question 38

pros and cons of dietary fiber in adult dog? Optimal fiber level?

Answer 38

Increases bulkiness that contributes to satiety
Helps weight loss in obese dogs (calorie dilution)
But can decrease digestibility of other nutrients

3-7% DM

Question 39

Slide 32

Answer 39

Safe upper limits of selected non-digestible CHOs

Question 40

Ca and P deficiency in adult dogs

Answer 40

Skeletal abnormalities (most important in growing dogs)

Question 41

Consequence of excess P

Answer 41

may accelerate progression of chronic renal disease in susceptible dogs (P needs to be excreted via kidneys)

Question 42

Ca : P ratio

Answer 42

Not less than 1:1