VTT 200 General Sciences Chemistry The Chemistry of Heat and the use of Nutrients by Animals

Three States of Matter Review by classic Example: Water What bonds link water molecules to each other? How does change in heat affect these bonds?

Thermochemistry:Study of Heat Energy Energy: defined as the capacity to do work or supply heat. Heat: a form of energy- heat flows from warm to cool objects or regions—that is why wind will blow from a warm area to a cool area Law of Conservation of Energy: just like matter… Energy is neither created or destroyed but moves from one place to another. All energy is accounted for as work, stored energy, or heat. Nutrients must be used for energy or stored or excreted as waste.

Thermochemistry… Heat Capacity of an object or animal: . Depends upon Mass: greater the mass, the greater the heat capacity EX: Smaller animals cool down faster than larger animals by releasing heat faster Animal’s can no longer absorb and maintain heat under 95 degrees—this is why organs begin to shut down and don’t function Animals cannot release heat when their temp climbs above 105 degrees;

Nutrition Needs Review What are the six Required nutrients? Which 3 produce energy for the animal? Which nutrient is most important?

Nutrition Needs Review Review of Vitamins, p. 296 Vitamin critical for blood clotting? Vitamin important for skin & coat? Vitamin important for bones? Vitamin B plays important role in which body system? What species need outside source of Vitamin C?

Nutrition Needs Review Review of Minerals, p. 292 What mineral is critical for blood health? What minerals are important for bones? 2 minerals critical for energy production? What mineral is important for skin/ coat? What part of the body has need for Iodine? Toxicity of what mineral leads to liver failure and death in many large animals?

Nutrition Needs Review Practice and Review of Dry Matter Basis calculations!!!

Energy & Calories Chemical calorie (c): the quantity of heat required to raise the temperature of 1gram of water by 1 degree celsius. 1000 calories (c) = 1 kilocalorie (kcal) 1 kcal = 1 Dietary Calorie (C) It is dietary calories which account for the heat/ energy needed to maintain animal’s body functions

Animal Nutritional Needs Resting Energy Rate (RER): energy needed to run basic functions like heart beating, lungs working, brain analyzing. Formula: 30 x wgt. in kg + 70 kcal = RER (Calories/day) for animals >5kg 50 x wgt. In kg + 70 kcal = RER (Calories/day) for animals <5kg .

Maintenance Energy Requirements This is the amount of energy needed by animals during the day—daily energy needs Maintenance Energy Requirements (MER) for: Cats: RER x 1.2= feline MER (Calories/day) Dogs: RER x 1.6 = canine MER 3rd Trimester Gestation: MER x 3-4 Lactation: MER x 4-6 Growth Period: MER x 2.5 Calculate RER & MER: 14# cat 90# dog Calculate MER if both are lactating

Exothermic & Endothermic Reactions Exothermic: energy released in the form of heat. Ex. Burning gasoline Cold-blooded animals release heat energy during bodily chemical reactions. That’s why lizards and snakes must have an external source of heat. Endothermic: energy absorbed. Ex. Humans contain heat from bodily reactions Warm-blooded animals absorb heat energy during bodily reactions and warm themselves when the environment is cold.