Pet Food Types and Macronutrients

• Commercial pet food options include dry kibble, wet food, frozen/freeze-dried, and home-cooked diets.
• Dry kibble is the most economical and convenient but potentially less palatable.
• Wet food is more expensive and palatable but has a high water content (70-85%) and increased environmental impact due to carbon emissions.
• Frozen or freeze-dried food is expensive, sometimes raw, and has a high water content and environmental impact.
• Home-cooked diets have a high risk of nutritional deficiencies, although, they are often chosen for their better palatability, use in food allergies, or in unique medical conditions where commercial diets are not appropriate.
• Balance IT can be used as a recipe generator for home-cooked meals for pets.
• Water is the most important aspect of a pet's diet.

Macronutrients

• Macronutrients, including proteins, make up a larger portion of a pet's diet as energy requirements
• Proteins are a source of essential amino acids, and generated by aerobic metabolism.
• Crude protein is calculated as Nitrogen % x 6.25 but that does not differentiate amino acid nitrogen vs. non-amino acid nitrogen (urea), which is toxic to monogastrics.
• Dogs and cats have higher protein requirements than humans.
• Cats require the highest protein intake and are carnivores.
• Protein must be highly digestible and bioavailable and includes by-products.
• Grains and gluten are a good source of protein for omnivores only.
• An exam of muscle condition score (MCS) and comparisons between the current diet to the animal's requirements will help when determining if protein intake is adequate.
• Lipids are a source of essential amino acids and are generated by aerobic metabolism.
• Fats are the most energy-dense macronutrient, with twice as much energy compared to others.
• Lipids are essential for lactating animals to meet their increased energy demand, and aid fat-soluble vitamin absorption, as well as neuro and retinal development.
• Types of fats include triglycerides (TRIG), phospholipids, and free fatty acids (FFAs).
• Saturated fats have no double bonds, examples are mammal fats and coconut oil.
• Unsaturated fats have mono (one double bond) and poly (2+ double bonds), with sunflower oil being an example of monounsaturated fat.

Polyunsaturated Fatty Acids (FAs)

• Polyunsaturated FAs are critical for skin and coat health.
• Omega-3 fatty acids are highly bioavailable, meaning the body absorbs them well and does not excrete them.
• Alpha-linolenic acid is required in dogs only and can be found in flaxseed oil.
• DHA/EPA is required in both dogs and cats, is marine-based, has anti-inflammatory properties, reduces osteoarthritis changes and the dose is 300 mg EPA + DHA / kg^0.75.
• Omega-6 fatty acids consist of linoleic acid, which is required in both dogs and cats.
• Arachidonic acid is required in cats only. Examples are vegetable oil, poultry fat, corn oil, and soybean oil, additionally, they play an important role in immune function.
• All essential fatty acids are polyunsaturated fatty acids!

Carbohydrates

• Short-chain FAs are VFAs that are non-essential in the diet, because they are produced by microbes within the GI tract.
• Complex carbohydrates are essential for herbivores and beneficial for GI health, the microbiome, and the immune system in dogs and cats
• Carbohydrates balance protein and fat within the diet, especially when decreasing one nutrient another needs to be balanced.
• They are generated by anaerobic metabolism.
• Psyllium has very low fermentability and is a viscous fiber, which binds water to treat diarrhea and help form stool.
• Beet pulp has moderate fermentability and low solubility and is mixed fiber, but a byproduct of whole fiber.
• Crude fiber is a poor representation of total dietary fiber.

Types of Carbohydrates

• Non-fiber carbohydrates are digestible and supply dietary energy, euglycemia in dogs, and glycogen, examples include starch (polysaccharide).
• Fiber carbohydrates are non-digestible, promote GI health, glucose absorption, and satiety,while also reducing diet digestibility (amount and type-dependent), examples include cellulose.

Molecular Structure

• Molecular structures include monosaccharides (glucose, fructose, and galactose), disaccharides (lactose, sucrose, maltose, trehalose), polysaccharides (starch (non-fiber) and cellulose (fiber)), and oligosaccharides ("pre-biotic" fibers like Fructooligosaccharides common in supplements).
• Proteins are composed of amino acids connected by peptide bonds, while amino acids are nitrogen-containing molecules. When selecting high-quality food, targeting essential amino acids is best.

Micronutrients

• Micronutrients make up a smaller portion of the diet.
• They are derived from the diet and GI microbes (B vitamins with herbivores and vitamin K).
• Assessing micronutrient status requires more than one single test.
• Macrominerals are required in larger amounts, such as calcium (Ca).
• Calcium deficiencies can cause decreased bone density (osteopenia, rickets), milk fever, and eclampsia.
• Phosphorous toxicity is associated with bone loss.
• Sodium is a cation and an alkalizer, neutralizing acids in urine to prevent kidney stones.
• Chloride is a strong anion and acidifier reducing pH when added, while also being helpful in urolith management.
• Magnesium deficiencies result in grass tetany with muscle weakness.
• Potassium(K) is found in forage, fruit, and veggies, while a cation alkalizer neutralizes acids in urine preventing kidney stones.
• Potassium deficiencies can cause hypokalemia secondary to diuretics and CKD, as well as cardiac arrhythmias.
• Potassium toxicity can cause hyperkalemia secondary to CKD.
• Sulfur is an anion and an acidifier.

Microminerals

• Microminerals are required in smaller amounts.
• Zinc is important to GI health and deficiency causes poor skin and coat as well as decreased appetite and diarrhea.
• Copper and selenium are important antioxidants as enzyme cofactors in thyroid hormone production.
• Selenium deficiencies cause muscular disorders.
• Iodine is a component of thyroid hormones.
• Iodine deficiency = goiter, poor skin and haircoat.
• Iron deficiencies cause anemia.
• A nutritional assessment will help determine the cause before supplementing with iron.
• Manganese, molybdenum, and cobalt may have deficiencies that cause coat color discoloration (rust), anemia and poor skin, toxicity can cause copper hepatopathy.

Vitamins

• Fat-soluble vitamins include K, A, D, and E.
• Vitamin K is important in blood clotting (II, VII, IX, X) and is produced by gut microbes.
• Vitamin A is required in cats in the active form (retinal), because cats cannot convert carotenoids to vitamin A like dogs can, its deficiency causes poor appetite, weight loss, and poor skin and coat, and its toxicity leads to hypercalcemia.
• Vitamin D increases Calcium and P absorption in bones and gut, must be required in a dogs and cats diet as they cannot synthesize it from the sun, toxicity leads to hypercalcemia and production of Ca oxalate urinary stones.
• Vitamin E is a preservative for pet foods that contain PUFAs (ex- OMEGAs), has no known safe upper limit (toxicity not seen as required in the diet of dogs and cats.

Water-Soluble Vitamins

• Water-soluble vitamins include Cobalamin / B12, Folate / B9, Niacin / B3, Pyridoxine / B6, Riboflavin / B2, Thiamine / B1.
• Cobalamin / B12 deficiencies cause anemia and GI disease.
• Folate / B9 deficiencies and excesses cause GI disease and cleft palate.
• Niacin / B3 deficiencies cause oral ulcerations and inflammation.
• A thiamine deficiency indicates a neurological condition.
• Folic acid and vitamin B12 deficiencies can manifest as gastrointestinal disease.
• Foods can be rich in a mineral, which does not necessarily mean it is bioavailable, because there is different ingredient interaction and absorption.
• Mineral supplements should not be given on top of a complete and balanced diet, unless there is a specific indication.
• Hyperparathyroidism can cause increased calcium and decreased phosphorus from increased kidney excretion- such as milk and meat diets; this phosphorus deficiency association with nutritional secondary hyperparathyroidism can lead to bone demineralization.
• A pet food that is complete and balanced= meets all essential nutrient needs and in appropriate rations.
• Most deficiencies are associated with poor appetite and weight loss.
• Nutritional Assessment should be performed by assessing the patient, current diet, and feeding management. Ideal body condition score (BCS) is 4 or 5/9 in dogs, and 5/9 in cats.
• Normal muscle condition score (MCS) is 3/3, mild is 2/3, moderate is 1/3, and severe (cachexia and sarcopenia due to age-related muscle mass loss) is 0/3.

Pet Food Selection Steps

• Pet food selection involves ensuring:

1. That the product is safe
2. That nutrition is balanced
3. That it is appropriate for the pet which is based on the animal and their nutritional requirements as determined by assessments of the patient.

• Grain-free diets should be avoided if PEAs are the primary carb source, as there is a possible link to dilated cardiomyopathy.
• Methods to assess a diet involve knowing the AAFCO nutrient guidelines on a dry matter basis (water removed) and feeding tests.
• Two categories for AAFCO nutrient profile guidelines are growth and reproduction and adult maintenance.
• Energy calculations involve looking at the food package via feeding tests.

Formulas

• Basal energy requirement is the minimum requirement for body functions to survive.
• Resting energy requirement is the requirement to perform basic functions at rest.
• The main measurement is kcal/day metabolizable energy.
• The resting energy requirement (RER) equation is BW(kg)^0.75 x 70.
• Daily energy requirement includes calculating for adult, growth, work, etc; and uses the equation DER = RER x lifestage factor.
• Daily energy requirement in dogs: 1.4-1.6 (1- obese).
• Daily energy requirement in cats: 1.2-1.4 (0.8- obese).
• 0.5-2% p/week = weight loss in cats (normally high efficient).
• 1-2% p/week = weight loss in dogs.
• Changes post-spaying/neutering can lead to energy requirement changes (important to discuss with owners these changes as energy requirements will decline, meaning the animal should eat less).
• Cats have a lower DER compared to dogs at the same lifestage because cats are metabolically more efficient.
• Metabolizable energy indicates how the energy content of food is expressed on the food packaging.
• Digestible energy = gross energy - fecal energy) - urine / gas energy.
• Use modified atwater factors of pet food to assess lipids (increased energy dense), proteins, and carbs. Different energy requirements vary between animals and human nutrition.
• Avoid grain-free diets if PEAs are a primary carb source, that is possibly linked to dilated cardiomyopathy.

Weaning and Growing Animal Diets

• Weaning nutrition: 4-weeks old require 4 feedings/day.
• 4 weeks old = 4 weeks of feeding 4 meals p/day.
• Developmental orthopedic disease (DOD) is hypertrophy, lack of endochondrial ossification (normal bone process), and calcification degeneration among others.
• Risk factors for DOD are excess dietary energy, rapidly growing, obesity, nutrient deficiencies which can also cause a lack of a complete and balanced diet.
• Diets should be well substantiated for growth, and can also occur from excess nutrients such as calcium deficiencies and excesses, prone to ortho disease in growing animals via adding supplements to the diet.
• Treats should only make up less than 10% of the diet.
• If growing animal diets are fed, it is best to feed all life stages (growth and repro + maintenance).
• Puppies should state on packaging whether they are for small or large breeds packaging, also they should differ in energy requirements.
• An example is that larger breed puppies have a decreased calcium requirement since small breeds have an increased risk factor for DOD as they have a longer growth period.
• Feed 2-4 meals/day (4 weeks initially post-weaning) and do not free-feed.
• Use caution with homemade diets as any nutrient deficiencies results negative lifelong effects that can equal death. Do not give supplements to growing animals.
• A pet will reach their full adult size depending on breed size and age.
• Cats = 12 months most breeds (15 months for Maine Coons).
• There should be a transition from growth/puppy to adult food UNLESS an adult pet is underweight that has no underlying medical condition because growth diets aid in weight gain with increased energy need.
• Growing animal energy requirements: RER = 70 x BW^0.75 and decreases with increased age or post neuter/spay as it decreases energy requirements, indicating they should be fed less.
• Waltham Charts assess the growth of animals until they reach adult size and account for age, BW, BCS, and MCS of either male or female.

Pet Nutrition Alliance

• Growth travels along sentinel lines and should not be over or underweight.
• Pet Nutrition Alliance's (PNA) energy calculations and manufacturing reports occur when some companies do not respond (can directly contact manufacturer), and the only thing they can not provide is a food recipe.
• AAFCO does not produce nutrient profile guidelines for seniors, which indicates normally feed adult maintenance diets because there is no need to change their diet if they are doing well.
• Supplements are regulated at the state and federal level; ex) glucosamine and chondroitin sulfate. They have low oral bioavailability where they are mostly excreted and a smaller amount is actually absorbed.
• Administer OMEGA-3s (fish oil) to avoid sarcopenia with increased age.

Omega in Adult Maintenance Diets

• Omegas require an inverse n6:n3 ratio (ex) 1,000mg OMEGA-6s + 300mg OMEGA-3s p/day.
• Cognitive dysfunction can be avoided and improved with antioxidants and precursors, L-carnitine, MCTs, OMEGA-3s, and B vitamins.
• Breeding animals require BCS 5/9 - 6/9.
• Underfeeding leads to lower %'s of pregnancies, smaller litter sizes, and reduced immunity. Overfeeding leads to small litter sizes, mastitis, and long-term health consequences.
• Water requirements are greater than or equal to 120ml/kg BW, at 2-3 times higher compared to maintenance and is especially important in lactation.
• Bitches will increase weight by 15-25% from breeding to whelping and are nutritionally similar to adult maintenance at the beginning, although requirements can increase 25-50% by feeding gestation/lactation diets at 4 weeks gestation.
• Queens can increase weight by 15-40% from breeding to whelping but need to prep for lactation because that can not effectively meet energy needs, it can be meet with feed for gestation/lactation diet at beginning.
• Fat needs to be high in energy density, requiring essential FA's, and is importantly composed of DHA for feti/offspring retinal/neuro development.
• Be cautious of hypocalcemia which can cause tetany (eclampsia) in the bitch, especially in small breeds, anorexia, post-whelping / lactation period, and large puppy food (lower in Ca), and can lead to additional risk of altering Ca homeostasis with overs upplementation of calcium
• Use micronutrients for fetal development.
• Folic acid deficiency associations can cause cleft palate and require good gestation/lactation diets.
• Zinc deficiency associations with small litters and fetal resorption require caution when the owners feed supplements/excess nutrients.
• Dry food is more energy-dense than canned on an as-fed basis.
• Palatants for pre-whelping / queening can include ice cream, milk, yogurt, parmesan, cooked meat, and cooked egg, but only in moderation.

Weaning & Pet Food Labels

• Slow transition to food via introducing solid food during week 4-5 with equal parts kibble and 2 parts water/milk replacer, during week 5-6 introduce 1 part kibble and 1 part water, during week 6-7 introduce 1 part kibble and 0.5 parts water, and during week 7-8 include exclusively dry food.
• Sporting and working dogs need high energy intakes: RER x 2.0-8.0 (higher for sled dogs).
• Feed greater than 4 hours prior to the activity and offer food within 2 hours of completion.
• Pet food labels are regulated the same as supplements.
• FDA (handles regulations and recalls), FTC, and state feed control officials regulate these.
• Most recalls are voluntary handled by the manufacturer themselves (not FDA-involuntary). Report EVERYTHING to the FDA safety reporting portal.
• AAFCO is NOT a regulatory body but members are regulators from the state and FDA (assessing investment events, and that companies are following AAFCO guidelines, and reporting issues to the FDA).
• AAFCO approved pet foods do NOT exist.
• Most important requirements include the product and brand name.
• Can only say "100%" if it is one ingredient only! (NOT complete and balanced food, ex- meal topper).
• Use "95%" if the ingredient is 95% product by weight.
• Use "25%" must have “dinner, platter, entree, formula, or recipe within description (ex) duck, chicken, peas meal making up together at least 25% of product ).
• Use "3%" when greater than one ingredient and each ingredient is 3% by weight (→ must say “with").
• "Flavor" must be the same word as the ingredient (no minimum amount).
• Guaranteed analysis must include the minimums for crude protein and fat a well as listing their maximums, but these are not measures of quality.
• Listing can have an As Fed basis (water included).
• Ingredients are listed in order by decreasing weight, with the heaviest ingredients listed first, and lightest ones (micronutrients) are at the bottom.
• They must meet a listed nutritional adequacy statement.
• Listing requires "formulation to meet the nutritional levels established by the AAFCO Dog (or Cat) Food Nutrient Profiles for Maintenance, growth, gestation, or all life stages (including or excluding large breed dogs- lower max for Ca).”

Animal Food Tests with AAFCO

• Animal Feed tests with AAFCO procedures must substantiate that it provides complete and balanced nutrition for the animal's maintenance, growth, gestation, or all life stages (including or excluding large breed dogs), and specify what lifestage this food is indicated for.
• A feeding trial is required to put it on the market.
• "This product is intended for intermittent or supplemental feeding only."
• Directions normally based on the the animal's weight range (must be in common unit).
• Calorie statements include the animal's ME on "as fed" basis, kcal/kg required, and that it is "Calculated" by modified Atwater formula or feeding tests.
• Raw diets have highest risk of pathogens, such as Salmonella and Listeria.
• Natural, organic, and human-grade materials are regulated only when applying to manufacturing facilities.

Natural Diets, Organic Diets, and Human-Grade

• Natural diets are unprocessed OR subject to physical processing, heat processing, rendering, purification, extraction, hydrolysis, enzymolysis or fermentation but not chemically synthetic process or any additives EXCEPT in unavoidable amounts, where non-natural foods are allowed in “natural” pet food which the Regulatory meaning as AAFCO definition. Organic diets refers to the processing of the product NOT the quality of the product.
• Regulatory can be found by reviewing the USDA seal.
• Human-grade refers to food as a whole where it specifies that EVERY ingredient must be stored, handled, processed, and transported in a way consistent with federal human food laws.
• Human-grade must be registered as both FDA food and feed facilities.
• By-products follow the AAFCO definition, where poultry is slaughtered poultry that are free from fecal content and foreign matter except in trace amounts, and the animal meat comes from mammals that do NOT include hair, horns, teeth and hoofs.

Grains

• Organ meat is a greater source of micronutrients.
• Grains source of energy for both starch and essential nutrients.
• Grains are not a filler, corn is a more concentrated source of micronutrients, and is grain-free.
• Grain-free poses the issue of possibly breaking down food which isn't fully understood.
• "Fresh food" Has potential to have higher digestibility when compared to kibble.
• Can be complete and balanced as long as the owner knows how to formulate it
• Vegetarian diets can put cats at a major RISK of arachidonic acid, vitamin B12, retinol, and AA deficiencies.
• Meals → rendering can occur where fat and water are removed.
• 50% of dogs and cats = overweight (mostly upward/steady trend).

Weight Loss Diets

• Includes a higher percentage of crude protein and fiber (TDF = preferred to assess).
• Higher fiber content helps to decrease incidence of destructive food-seeking behavior.
• Be caution to pets that defecate in more pain when defecating, as these pets would not want higher fiber content to due to increased defecation.
• Encourage more veggies, smaller multiple meals p/day, and puzzle toys.