Thermodynamics and Nutrition

Mass and Energy Transfer During Lactation in Harbor Seals

• This study focuses on the energetic costs of fat mobilization during lactation in harbor seals (Phoca vitulina).

• Researches used morphometric and isotopic methods on Sable Island to study fat and energy reserves.

• The initial mass of the harbor seal mothers ranged from 87 to 94 kg.

• Maternal mass decreased by 33% during the first 19 days out of the 24-day lactation period.

• Most of the mass loss, about 68.8%, comes from the sculp (skin and blubber).

• Maternal body fat decreased from 24% at the beginning of lactation to about 7% by day 19 postpartum.

• Mothers lost 16.3 kg (78.7%) of stored fat and 3.1 kg (20.0%) of stored protein.

• Mothers used 713.8 MJ (169 Mcal), or 60.5%, of their stored energy.

• Newborn pups initially contain 93.0 MJ (22.1 Mcal) of energy, split between fat (46.4%) and protein (53.6%).

• Pup body mass increased from 10.6 kg to 25.8 kg.

• Sculp mass accounted for 62.7% of the mass gained by the pup.

• Total body fat of pups increased from 11% at birth to 35% at 19 days.

• Pups deposited 346.8 MJ (82.2 Mcal), or 48.7%, of the energy their mothers withdrew from storage.

Wildlife Nutrition Studies

• The number of wildlife nutrition studies has increased exponentially from 1930 to 1990.

• Early wildlife nutrition studies focused on food habits and foraging strategies.

• More recent researches shifted towards energy, protein, minerals, vitamins, and water requirements.

• Differences exist between wildlife and domestic animal nutrition:

  • Wildlife has undergone long-term evolution and selection, while domestic animals have been subject to short-term changes

    through human selection.

  • There are fewer cost incentives for wildlife management compared to livestock production.

  • The number of wildlife species studied is much larger than the number of domestic animals.

Nutritional Wisdom and Captive Wildlife Studies

• Most wildlife nutrition studies are conducted with captive wildlife.
• It's important for captive animals to be well-conditioned before any studies.
• There's a focus on understanding animals' nutritional wisdom about minerals and vitamins
• The studies analyze wildlife nutrition and disease interactions (Selenium, thiamin).
• Captive wildlife studies should be designed to be ecologically relevant, mirroring free-ranging wildlife.

Designing Meaningful Wildlife Studies

• The annual salmon consumption by Kodiak brown bears is estimated at 3.77 ± 0.16 million kg.

• This is equal to 29% of Kodiak's salmon escapement, 8% of the commercial harvest, and 6% of the total escapement

    and commercial harvest.
  

Basic Nutritional Requirements

• Essential nutritional requirements include energy, protein, water, minerals (17), vitamins(14), and essential fatty acids (2-4).

• Energy is neither created nor destroyed based on the laws of thermodynamics.

• Using the first law in nutrition:

  • 10 units of food energy = Gross energy
    • 2 units are lost in feces = 80% Digestion or Digestible energy
    • 2 units lost in urinary energy = Internal metabolic losses or Metabolizable enery
  • 4 units of heat, and 2 units of fat, growth, or milk (Gain or retention) which equals Net energy

Energy Measurement

• A calorie is the amount of energy required to raise 1 g of water by 1°C.
• A bomb calorimeter is used to find an object's "Gross energy content".
• Glucose example

Dietary Substances and Nutritional Implications

• Energy content (kcal/g) varies across different substances:

  • Water and sodium chloride: 0 kcal/g
  • Wheat or corn: 4.1 to 4.2 kcal/g (dry)
  • Millet: 4.1 kcal/g (dry)
  • Grass: 4.4 kcal/g (dry), 1.3 kcal/g (fresh, 70% water)
  • Sunflower seed kernels: 5.9 kcal/g
  • Walnuts: 6.5 kcal/g (dry)
  • Butter: 7.2 kcal/g (18% water), 8.8 kcal/g (dry)
  • Vegetable oils: 8.4 kcal/g (dry)

• Other food comparisons:

  • Steak: 2.71 kcal/g (fresh, 61% water), 6.95 kcal/g (dry)
  • Whole cow's milk: 0.72 kcal/g fresh (13% dry matter, 87% water), 5.54 kcal/g (dry)
  • Hooded seal milk: 5.88 kcal/g fresh (70% dry matter, 30% water), 8.4 kcal/g (dry)

Bloomin Onion comparison

• Large raw onion:

  • Weight: 340 g (303 g water), 6 g fiber
  • Fat: 0 g
  • Protein: 4 g
  • Digestible carbohydrates: 27 g
  • Energy content: 130 kcal.

• Bloomin’ Onion:

  • Weight: 611 g

  • Fat: 155 g (from 1396 kcal)

  • Protein: 18 g (from 97 kcal)

  • Digestible carbohydrates: 123 g (492 kcal)

  • Menu lists 1950 kcal, with 71% from fat and 25% from carbohydrates,

    due to battering and frying, energy content Increases by 15 times!

Essential Amino Acids and Taurine

• Essential amino acids include Arginine, Histidine, Isoleucine, Leucine, Threonine, Lysine, Methionine, Phenylalanine, Tryptophan, and Valine.

• Taurine is essential for cats but not necessarily for dogs.

• Most wildlife studies report "Crude protein" . "Crude protein" is calculated: = N x 6.25.

Taurine Deficiency in Wolves

• Captive maned wolves historically suffer from complications of cystinuria, prompting the the development of a specialized diet in 1998.

• Diet: moderate protein, low sulfur-containing amino acids (cysteine and methionine).

• Taurine, an animal derivative, stems from methionine and cystine, while found in minimal in plants.

• Deficiency results in issues like retinal degeneration, heart failure, and digestive/reproductive issues.

• Experimental diets for maned wolves were tested.

• Plant sources (soybean meal, corn) provided 60% of the protein in the new diet.

• Both diets were later supplemented with taurine at 0.3%.

WSU Bear Diet ingredients

• Includes Fish Meal, Feeding Oat Meal, Linseed Meal, Fish Oil, Porcine Animal Fat Preserved with BHA and Citric Acid, Ground Flaxseed, etc

Taurine In Energy Drinks

• Daily taurine intake is generally below 200 mg/day, even with high meat consumption.
• European Food Safety Authority found no adverse effects up to 1,000 mg taurine.
• It has been shown to prevent oxidative stress induced by excercise in mice
• Review in 2008; no health effects with amounts in energy drinks

Minerals - Key aspects include function, abundance, and classification:

• Involved in Body Process: All processes with elements beside C,H,O,N

• Abundance in the body: comprises 3 to 5% of body mass.

• Classifications:

  • Macroelements: Ca, P, Na, K, Mg, Cl
  • Micro/Trace elements - Fe, Zn, Manganese, Copper, Lodine, Selenium, and fluoride
  • UltraTrace Elements: Silicon, vanadium, nickel arsenic

Calcium and Phosphorus

• Calcium is for skeletal formation, antler growth, blood clotting, eggshell development, and nerve/muscle function.

  • Bone contains ratio of 2 parts Ca: 1 part P, and is 60% protein.
  • Egg shells consist of 98% CaCO3.

• Phosphorus is for energy metabolism and all metabolic transformations.

• Key info on Ca and P needs:

  • Ca:P ratio is important, best ratio is 2:1 to 1:1.
  • Ca3(PO4)2 + Additional P ⇌ Ca + PO4
  • High fat diets can bind Ca, creating insoluble complexes

Diets

• Invertebreate without a calcified exoskelton
• Fruits, seeds and nuts
• Meat or deboned vertebrate flesh

Symptoms and Scientific Classification

Deficiencies = problem

• Deficiency may equal Metabolic Bone Disease or Nutritional Secondary Hyperthyroidism
• Calcintonin comes from thyriod

Studies and Deficiencies

• Calcium deficiencies:
  • Fairly common in the both wild, in some pets, and some captive wildlife being fed inadequate diets.
  • Scientific names: Metabolic bone disease or Nutritional Secondary Hyperparathyroidism. This name arises because 1) Nutritional in origin, 2) Not a primary tumor, and 3) Results in enlargement of the parathyroid gland.
  • Hormones in the control of blood calcium levels: Ca:P Ratio = important

Sodium Facts

• Functions - Evolution of terrestrial life, chief cation of extracellular fluid, reg body fluid (osmotic),

• Muscle contraction = nerve impulse transmission

• If deficient - weakness, incoordination, adrenal hypertrophy, decreased fiuld, shock , death

Source and Function of Sodium in Relation to Diet

• Abundant, required by animals; exception - desert Saltbush
  • General location - low in alpine, high rainfall; high - coastal marone areas, desert