11: Life-cycle nutrition of dogs (older dogs and reproduction) Flashcards
What is the life expectancy of a smaller dog? When are dogs considered old?
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
Goal of older dog nutrition
- optimize of quality and longevity
- minimization of disease
- delay or elimination of cancer, kidney disease, and heart disease
What are the effects of aging on a dogs body?
- gradual weight gain
- development of age-related physical and behavioural changes
- increased vulnerability to disease
Concerns with water requirement of older dogs? Solution?
- more prone to dehydration: possible osmoregulatory disturbances, medications, and chronic renal disease
Solution = continuous access to fresh, clean water supply. Monitor water intake
What happens to the energy requirement of dogs as they age? Changes that impact this requirement?
Decreases
- lean body mass decreases (less protein tissue/turnover)
- subcutaneous fat increases
- basal metabolic rate gradually declines
- body temp may decrease
- less active
Energy requirement of older dogs
105 kcal ME/BW kg^0.75
Changes in energy requirement of very old dogs
- often underweight
- need an energy dense food
How do protein requirements change in older dogs
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
Potential concern with feeding high protein diets to older dogs
If kidney function is impaired, high protein diets may accelerate renal disease (more pressure on the kidney to excrete urea)
Fat requirement changes in older dogs? Very old dogs?
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
Considerations for Ca and P intake in older dogs? Ratio?
Avoid excess P intake (clinical or subclinical renal disease often present in older dogs)
Ca:P ratio = 1:1
Pros and cons of feeding fibre to older dogs
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)
What are important facts about requirements during pregnancy and lactation?
- periods of high physiological stress
- females undergo greatest extremes during entire reproductive cycle
- improper nutrition can reduce reproductive performance
Goals of good reproductive feeding program
- 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
When should optimal nutrition start for reproducing animals?
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
What is flushing in reproducing dogs?
Elevated plane of nutrition for a couple days to help female get pregnant (one or two days)
Slide 14, 15
Body condition scoring
Food intake/body weight curves**
Daily metabolizable energy requirement for bitches in late gestation
ME = 130 kcal x kg BW^0.75 (MER) + 26 kcal x kg BW (growth)
Considerations for protein requirements during gestation? Protein deficiency during pregnancy?
- 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
Why might dogs have an arginine requirement during gestation?
If feeding a lot of protein, a lot of amino acids are deaminated and N needs to be excreted
Why increase fat levels during gestation?
Increases digestibility, energy provision and nitrogen retention
How much fat in the diet of a gestating dog depends on…
- litter size
- body condition
- food intake
- giant-breed bitches need high-energy throughout gestation
Ideal ratio between linleic acid and a-linolenic acid during gestation?
2.6:16
What is the CHO requirement during gestation?
- 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
Consequences of feeding starch and sugar free food during gestation
- 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
If no CHOs are provided during gestation, what must occur?
Protein intake must double for gluconeogenesis
Ca and P requirements in last five weeks of gestation? Consequences of excessive intake of Ca during pregnancy?
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
Which trace elements may be required during gestation?
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
Nutrient requirements during lactation is related to? What are requirements higher than?
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
What is the first nutrient needed for lactation? Why? Requirement?
Water
- large quantities for milk production
- thermoregulation
- availability of clean, fresh water at all times
- water requirement in mL = energy requirement in kcal
Energy is required during lactation for…
maintenance + milk production
What is the limiting factor for meeting energy requirement during lactation?
Energy intake
If energy density is too low there is a physical limitation to eat enough food = worsens negative energy balance in early lactation
Maintenance energy requirement during lactation? Why is is different than average adult dogs
higher bc stress and increased activity associated with caring for puppies (body is more metabolically active)
145 kcal ME per BW kg ^0.75
How is the energy requirement for milk production estimated? (3)
- gross energy for milk
- efficiency of converting maternal energy into milk energy
- quantity of milk produced daily
Quantity of milk produced is related to…
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
Slide 29
Look: ME calculation lactation
Changes in protein requirement for lactation?
- 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
How does fat requirement change in lactation? How does this affect milk fat/f.a. composition?
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 %
Why do bitches need CHOs during lactation? Recommendation?
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
How do we determine Ca and P requirements during lactation? Depends on
Determined by mineral excretion in milk
Depends on number of nursing puppies
Other nutritional requirements during lactation
Iron: requirement increases slightly. Mature milk low in Fe, colostrum rich in Fe (first 48h)
Copper: requirements increase more than for energy
Changes to digestibility of nutrients during lactation? How
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)
