8b Nutrient Requirements of Dogs Flashcards
What is the definition of an adult dog?
- fully grown at 12 months
- not over 5-7 years old
Why are domestic canids the most diverse mammalian species in mature body weight and size?
- dogs had many different jobs
What is the goal of nutritional management of dogs?
- different objective than livestock, except for breeding herd
- maximize longevity, quality of life and disease prevention
What are the factors that influence energy requirements of dogs?
- gender and neuter status
- breed
- age (growth, sedentary dogs)
- reproduction
- activity level
- environment
Why do female dogs need less energy?
- less lean body mass than males
- more body fat
- lean body mass accounts for BMR
Why do neutered dogs need less energy?
- but higher food intake
- lack of appetite suppressing estrogen in neutered bitches
- decrease in physical activity
- prone to obesity
How does breed affect energy requirements?
- different breeds may be at risk for specific diseases or metabolic alterations
- MER (differences in lean body mass, temperament and activity level)
How does age affect requirements?
- increased prevalence of dental disease, obesity and kidney disease will increase after 5-7 years of age
How does activity level influence energy requirements?
- significantly influences energy requirements (standing requires 40% more energy than lying)
- consistently higher level of physical activity increases lean body mass
- activity cannot be defined precisely
What can be used to monitor body mass?
- a scale
- ultrasound can be used to measure thickness of muscle or fat layer
How can environment affect energy requirement?
- temperature, humidity, type of housing, stress level and degree of acclimatization
- isolative characteristics of skin and coat
- difference in stature, behaviour and activity
What is the difference in lower critical temperature between breeds?
- minimum metabolic rate
- long haired 15-20C
- short haired 20-25C
- arctic breeds 10-15C
How do energy requirements change in hot or cold weather?
- dog kept outside needs 10-90% more energy than during optimal weather
- for body cooling, small increase in energy requirement, drastic increase in water requirement
Describe the basis for establishing energy requirements.
- energy requirements of animals with widely differing weights not directly related to BW
- more closely related to BW^0.75
- amount of energy used by the body is also related to total body surface area, not only animals weight (metabolic body weight)
What is the equation for maintenance energy requirements of dogs?
MER = 130 kcal ME x BW^0.75
- MER = BMR + thermoregulation + regular activity
Describe the importance of water.
- 56% of adult dogs BW
- body has limited capacity to store water
- water deprivation will result in death
- require constant source of water to replace losses
What are some factors that affect voluntary water intake?
- environmental temperature (increase temp = increase intake)
- type of doet fed (dry = increase)
- activity level
- physiological state (lactation)
- health
- increased energy intake cause more metabolic waste products to be produced, so require more water to excrete)
- high protein diet will also need more water to excrete urea
How much water is produced by metabolism?
- 5-10% of total daily water intake
How can we estimate animals’ water requirement?
1kcal of energy = 1ml of water
Describe protein requirement
- no benefit of extra protein when AA requirement is met
- need just enough for maintenance and activity
What factors affect protein requirement?
- biological value and protein digestibility
What is biological value?
ability of a protein to provide ratio of amino acids for protein synthesis
How to assess protein and AA requirement?
- adult: nitrogen balance: Nfood-Nfeces-Nurine
- growing animals: weight gain
What does apparent mean?
- not correcting for endogenous losses
Why is AID more accurate than ATTD?
- no absorption of essential amino acids in large intestine and microbial protein may be in feces from fermentation in handgun
Why is arginine of special importance?
- key intermediate in urea cycle
- release of several hormones and metabolic mediators
- precursor of biogenic amines
- precursor of neurotransmitters
What happens with an arginine deficiency?
- develop signs of ammonia toxicity
Describe fat requirement of adult dogs.
- tolerate high amounts of fat (70%)
- adapt to wide range of fat types and amounts
- tallow low in linoleic acid
- minimal amounts of fat when essential fatty acids adequate
What kind of fat is more easily digested?
- unsaturated more easily digested and absorbed
Which fatty acids can the dog synthesize?
- can synthesize alpha-linoleic and arachidonic acid from linoleic acid
- but limited ability to manufacture arachidonic acid (conditionally essential)
What happens with too low levels of fat in diet?
- deficiencies in total energy
- essential fatty acid deficiency leads to hair loss, development of dry dull coat and skin lesions and infections, decreased food palatability
What happens when too much fat is provided?
- diarrhea
- weight gain and obesity due to high palatability of energy dense diet
What is the carb requirement for adult dogs?
- do not have carb requirement because can make glucose from protein and fat
- there is a requirement for glucose and glucose precursors though
Why do dogs need fiber?
- increases bulkiness that contributes to satiety
- helps weight loss in obese dogs (calorie dilution)
- but can decrease digestibility of other nutrients
what is the optimal fiber amount?
3-7% DM
Describe Ca and P requirement
- deficiency can lead to skeletal abnormalities
- excessive P may accelerate progression of chronic renal disease
- ratio not less than 1:1
