10: Life cycle nutrition of growing dogs Flashcards
Three critical phases during first 12 months of life
- Nursing phase
- Weaning period
- Post-weaning period
Mortality in newborn dogs
10 to 30% in 1st week of life
Birth weight highly correlated to mortality
Body temperature in newborn dogs
- Poikilothermic (body temp similar to environment) during first 3 weeks
- low levels of body fat
- need warm environment
- bitch may push puppy away or neglect it if it has low skin temperature
When is colostrum produced? DM content?
24 to 48 h after giving birth
High DM content
- viscous and sticky
- suckling can be difficult for weak puppies
- DM content decreases 12 to 24 hours after birth
Nutrients in colostrum
- 2x as much protein as mature milk (globulins (IgG))
- high levels of Ca, Mg, P, Fe, Zn and Cu
- high in vitamin A
- low lactose level (1%)
- laxative effect
- growth factors (insulin-like growth factor 1)
Why is it so important for puppies to drink colostrum within 24 hours of birth
Immature immune system at birth
- depend on immunoglobulins in colostrum (passive transfer)
- transplacental transfer of immunoglobulins only 5 to 10% of IgG
- gut closure to Ig
Composition of milk?
Supports normal growth rate
- water, protein, fat, lactose, minerals and vitamins
- highly digestible
Energy requirement of puppies during nursing
Energy for maintenance + growth
25 kcal/100 g BW
Why do puppies huddle?
For warmth
Decrease maintenance requirements during first week of life (lower critical temp expands) = more E for growth
Protein digestibility of milk and nitrogen retention in first week
Digestibility = 99%
N retention = 90%
What aa is milk rich in
Rich in arginine, lysine and branched-chain aa
Body fat gain during first month of life? Therefore…
50% of BW gain is fat
After two weeks, 10% body fat
After 1 month, 17% body fat
Therefore milk must contain a lot of fat
Primary CHO in milk? How is it absorbed?
Lactose (3 to 3.5%)
Absorbed readily after digestion
- intestinal lactase activity high until 4 months of age
- pancreatic amylase insignificant at 4 wks
How does lactose control bacterial colonization? Health benefits?
Favours colonization of beneficial bacterial species (fermented into lactic acid in the gut decreases pH = exclusion of pathogenic bacteria)
To avoid diarrhea, lactose should be main CHO during first weeks
Sufficiency of Ca and P levels in milk? What is the concern?
Ca and P levels in milk are sufficient
But calcification of the skeleton does not keep pace with the increase in body size until after weaning
Milk as a source of iron? What is the solution
Milk is a poor source of Fe (puppy requirements higher than intake)
Fe accumulates in liver of fetus in last week of pregnancy and is used as a nutrient source until additional food (with Fe) is provided at weaning
What changes should you make to the bitches diet during weaning?
Restrict food intake 1 to 2 days before weaning. This means less nutrients will be available for milk production and mammary gland engorgement will reduce (prevent mastitis)
No food at weaning
Restrict food intake 1 to 2 days after weaning
Advantages of eating solid foods for puppies
- decreased reliance on bitch
- decreased nutritional burden of the bitch
- reduced Fe deficiency
- reduces weaning stress
When do puppies start eating solid food? How are they introduced to it?
Between 3 to 4 weeks (when deciduous teeth begin to erupt)
Come into contact with bitch’s food while playing, start eating small amounts
What kind of food should you use to introduce puppies to solid foods? Describe it
Gruel can stimulate food intake from 3 weeks of age
Blend a moist weaning puppy food or lactation food or growing food with warm water or milk replacer
High in nutrients, very digestible
Have more water at first, then decrease
What happens at five weeks of age? When is weaning complete?
5 weeks: puppies should eat sufficient quantities of solid food. Bitch’s milk production will decline
Weaning completed at 6 to 7 weeks (remove puppies from dam while feeding same diet)
Goal when feeding a growing dog?
Create a heallthy adult
- optimize (NOT maximize) growth
- minimize obestiy
- minimize development of orthopaedic disease
How does nutrition play a role in health and development during the growth phase
- immune system
- body composition
- growth rate
- skeletal development
Energy in the postweaning phase is required for…
Maintenance + growth
How much energy intake is used for growth in first weeks after weaning? What happens later?
50% energy intake for growth (50% maintenance)
Gradually, growth curve reaches a plateau and proportion of energy needed for maintenance becomes more important
Slides 22,23
Growth curves
What is the daily ME energy requirement formula for growth of puppies after weaning? What is P? Slide 25
MER x correction factor for growth
P = actual BW/mature BW
Important considerations of postweaning energy requirements in large and giant breed dogs
- optimal not maximal growth is important for proper skeletal development
- excessive energy intake impairs endochondral bone formation
When is arachidonic acid provided in the diet for dogs?
During postweaning growth
Added as a safety factor (adult dogs can synthesize it, not entirely sure about puppies)
When are fat requirements highest in dogs?
suckling period>postweaning>adult maintenance
When are Ca and P requirements greatest in dogs?
Greatest need during active formation of bones and teeth
Describe Ca homeostatic mechanisms in puppies
Less precise in puppies
- 2 to 6 months of age Ca absorption always >40%
- Absorption more regulated after 10 months
Recommended Ca:P ratio in growing dogs
1:1
Describe calcium deficiency in growing dogs? Excess?
Deficiency = nutritional secondary hyperparathyroidism
Decrease in blood (extracellular fluid) Ca = increase in parathyroid hormone -> increase in calcitriol. Calcitriol and PTH mobilize Ca from skeletal tissue (decrease in bone mineral content = osteomalacia, fractures)
High extracellular Ca = calcitonin release which deposits Ca into bone (decreased blood Ca) = large increase in bone mineral content (osteochondrosis, radius curvus, stunted growth, decreased bone turnover)
What happens when puppies are fed diets with low energy density and digestibility postweaning?
Puppy must eat large quantities of food
Increases risk of flatulence, vomiting, diarrhea, pot-bellied appearance
Puppy food should be more digestible than average
CHO recommendations postweaning?
No recommendation
Suggestion 20% DM CHo until 4 mo
