11: Life-cycle nutrition of dogs (older dogs and reproduction)

Question 1

What is the life expectancy of a smaller dog? When are dogs considered old?

Answer 1

Small dogs ~20 years

Considered old when they reach half of their life expectancy
- large breed dogs: 5 years of age
- small-breed dogs: 7 years of age

Question 2

Goal of older dog nutrition

Answer 2

• optimize of quality and longevity
• minimization of disease
• delay or elimination of cancer, kidney disease, and heart disease

Question 3

What are the effects of aging on a dogs body?

Answer 3

• gradual weight gain
• development of age-related physical and behavioural changes
• increased vulnerability to disease

Question 4

Concerns with water requirement of older dogs? Solution?

Answer 4

• more prone to dehydration: possible osmoregulatory disturbances, medications, and chronic renal disease

Solution = continuous access to fresh, clean water supply. Monitor water intake

Question 5

What happens to the energy requirement of dogs as they age? Changes that impact this requirement?

Answer 5

Decreases
- lean body mass decreases (less protein tissue/turnover)
- subcutaneous fat increases
- basal metabolic rate gradually declines
- body temp may decrease
- less active

Question 6

Energy requirement of older dogs

Answer 6

105 kcal ME/BW kg^0.75

Question 7

Changes in energy requirement of very old dogs

Answer 7

• often underweight
• need an energy dense food

Question 8

How do protein requirements change in older dogs

Answer 8

Decrease in lean body mass:
- alterations in protein synthesis and turnover
- higher protein intake required (approx 50% more) to prevent loss of lean body mass

Question 9

Potential concern with feeding high protein diets to older dogs

Answer 9

If kidney function is impaired, high protein diets may accelerate renal disease (more pressure on the kidney to excrete urea)

Question 10

Fat requirement changes in older dogs? Very old dogs?

Answer 10

Older:
- low fat intake to reduce risk of obesity
- essential f.a. requirements must be met

Very old dogs:
- higher fat intake to prevent BW loss
- more fat in food increases energy intake, palatability, protein use

Question 11

Considerations for Ca and P intake in older dogs? Ratio?

Answer 11

Avoid excess P intake (clinical or subclinical renal disease often present in older dogs)

Ca:P ratio = 1:1

Question 12

Pros and cons of feeding fibre to older dogs

Answer 12

Pros:
- older dogs prone to constipation (insoluble fiber)
- fiber decreases postprandial glycemic effect in older diabetic dogs (spikes in glucose)
- dilutes calories (good for old dogs, not very old)

Cons:
- can impair digestion of other nutrients (if fed too much)
- flatulence
- fiber dilutes calories
- very old dogs = decrease fiber to increase caloric density

Slide 11 (look)

Question 13

What are important facts about requirements during pregnancy and lactation?

Answer 13

• periods of high physiological stress
• females undergo greatest extremes during entire reproductive cycle
• improper nutrition can reduce reproductive performance

Question 14

Goals of good reproductive feeding program

Answer 14

• optimize conception
• number of puppies per litter
• ability of the bitch to deliver (rapidly available energy in form of glycogen)
• viability of prenatal and neonatal puppies

Question 15

When should optimal nutrition start for reproducing animals?

Answer 15

Should precede mating and conception
- only healthy dogs in good nutritional state should be used
- malnutrition before breeding is often unnoticed until puppies are born with low BW

Question 16

What is flushing in reproducing dogs?

Answer 16

Elevated plane of nutrition for a couple days to help female get pregnant (one or two days)

Question 17

Slide 14, 15

Answer 17

Body condition scoring

Food intake/body weight curves**

Question 18

Daily metabolizable energy requirement for bitches in late gestation

Answer 18

ME = 130 kcal x kg BW^0.75 (MER) + 26 kcal x kg BW (growth)

Question 19

Considerations for protein requirements during gestation? Protein deficiency during pregnancy?

Answer 19

• higher protein quality (increases vigor of newborn puppies and decreases neonatal mortality)
• protein deficiency during pregnancy = decrease birth weight, immunocompetence, increased mortality in first 48h

Question 20

Why might dogs have an arginine requirement during gestation?

Answer 20

If feeding a lot of protein, a lot of amino acids are deaminated and N needs to be excreted

Question 21

Why increase fat levels during gestation?

Answer 21

Increases digestibility, energy provision and nitrogen retention

Question 22

How much fat in the diet of a gestating dog depends on…

Answer 22

• litter size
• body condition
• food intake
• giant-breed bitches need high-energy throughout gestation

Question 23

Ideal ratio between linleic acid and a-linolenic acid during gestation?

Answer 23

2.6:16

Question 24

What is the CHO requirement during gestation?

Answer 24

• bitch needs digestible CHOs during pregnancy
• high metabolic requirement for glucose (50% of energy for fetal development is glucose)
• recommend ~20% of energy from CHOs

Question 25

Consequences of feeding starch and sugar free food during gestation

Answer 25

• increased weight loss
• decreased food intake
• decreased birth weight of puppies
• decreased neonatal survival of puppies
• increased risk of stillbirth
• increased risk of hypoglycemia and ketosis during late pregnancy
• decreased lactose concentration in milk

Slide 20

Question 26

If no CHOs are provided during gestation, what must occur?

Answer 26

Protein intake must double for gluconeogenesis

Question 27

Ca and P requirements in last five weeks of gestation? Consequences of excessive intake of Ca during pregnancy?

Answer 27

Lat 5 weeks Ca and P requirements increase by 60% (for rapid skeletal growth of puppies)

Excess Ca = decreased activity of parathyroid glands, predisposition to eclampsia (seizures) during lactation

Question 28

Which trace elements may be required during gestation?

Answer 28

Iron:
- Fe requirements very high during last week of gestation
- Fetuses store Fe in liver
- Colostrum is rich in Fe (milk is low in it)

Zinc:
- must be adequate
- deficiencies may lead to fetal resorption or fewer, less viable offspring

Question 29

Nutrient requirements during lactation is related to? What are requirements higher than?

Answer 29

Directly related to milk production (number of puppies)

Nutrient requirement higher than in any other adult lifestage and higher or equal to that of growth

Question 30

What is the first nutrient needed for lactation? Why? Requirement?

Answer 30

Water

• large quantities for milk production
• thermoregulation
• availability of clean, fresh water at all times
• water requirement in mL = energy requirement in kcal

Question 31

Energy is required during lactation for…

Answer 31

maintenance + milk production

Question 32

What is the limiting factor for meeting energy requirement during lactation?

Answer 32

Energy intake
If energy density is too low there is a physical limitation to eat enough food = worsens negative energy balance in early lactation

Question 33

Maintenance energy requirement during lactation? Why is is different than average adult dogs

Answer 33

higher bc stress and increased activity associated with caring for puppies (body is more metabolically active)

145 kcal ME per BW kg ^0.75

Question 34

How is the energy requirement for milk production estimated? (3)

Answer 34

1. gross energy for milk
2. efficiency of converting maternal energy into milk energy
3. quantity of milk produced daily

Question 35

Quantity of milk produced is related to…

Answer 35

Demand for milk
- directly related to litter size and stage of lactation
- large litters produce more milk
- more milk during mid-lactation than late lactation
- behaviour: more vigorous suckling = more milk

Question 36

Slide 29

Answer 36

Look: ME calculation lactation

Question 37

Changes in protein requirement for lactation?

Answer 37

• requirement for protein increases more than requirement for energy
• protein:energy ratio must be higher in foods than for adult maintenance
• 50 g CP/1000 kcal ME

Question 38

How does fat requirement change in lactation? How does this affect milk fat/f.a. composition?

Answer 38

Increase energy density of food to meet higher energy requirements and prevent negative E balance during early lactation

21.3 g/1000 kcal ME

Milk/f.a. composition varies; increasing fat DM % increases milk fat %

Question 39

Why do bitches need CHOs during lactation? Recommendation?

Answer 39

Bitches need soluble CHOs (sugars) for lactose production (cannot correct milk lactose levels with dietary protein)
If no CHOs, milk lactose 2% (should be 3 to 3.5%)

Recommend 10 to 20% of energy intake in form of soluble CHOs

Question 40

How do we determine Ca and P requirements during lactation? Depends on

Answer 40

Determined by mineral excretion in milk

Depends on number of nursing puppies

Question 41

Other nutritional requirements during lactation

Answer 41

Iron: requirement increases slightly. Mature milk low in Fe, colostrum rich in Fe (first 48h)

Copper: requirements increase more than for energy

Question 42

Changes to digestibility of nutrients during lactation? How

Answer 42

Digestibility of nutrients should increase

Increase protein digestibility by feeding more animal protein

Increase fat digestibility by feeding fat in form of oil (unsaturated)

Increase CHO digestibility by feeding more sugars, reducing fiber, making sure food is processed (open up starch)