Myths Flashcards
Feeding table scraps to dogs/cats is not harmful.
a. Usually fat trimmings and leftover meat, rarely vegetables
i. May be tasty but not balanced
b. Rule of thumb = no more than 5 to 10% of a pet’s total daily caloric intake
Dogs and cats can survive on an all-meat diet.
a. Muscle tissue alone cannot supply complete nutrition
i. Deficient in calcium, phosphorus, sodium, iron, copper, iodine, and several vitamins
b. Ancestors consume entire prey including bones, organs, and intestines
Cats prefer the taste of fish.
a. Same preference to many other animal-source proteins
b. Fish alone cannot supply complete nutrition
i. Deboned fish are deficient in calcium, sodium, iron, copper, and several vitamins
c. Some fish contain small bones that are difficult to remove before cooking
i. Perforation or obstruction risk
Tuna is safe to feed cats.
a. Excessive intake of tuna packaged in oil can result in vitamin E deficiency
i. High levels of polyunsaturated fatty acids
1. Increases animal’s vitamin E requirement
2. Without enough vitamin E, body fat is not sufficiently protected from oxidative degradation
a. Results in oxidative stress and the formation of peroxides
b. Accumulation of peroxides in adipose tissue leads to pansteatitis
b. Pansteatitis
i. Chronic inflammation
ii. Yellow-brown discoloration of body fat
iii. Clinical signs
1. Depression and anorexia
2. Hyperesthesia (sensitivity to touch) of the chest and abdomen
3. Reluctance to move and decreased agility
4. Presence of abnormal fat deposits under the skin and in the abdomen
5. Roughened hair coat
iv. Treatment
1. Dietary correction
2. Alpha-tocopherol administered orally (10-25 IU) twice daily for several weeks until all clinical signs have resolved
3. Corticosteroid therapy in severe cases to decrease inflammation and reduce pain
4. Prognosis for recovery is good, but may take several months
c. Same concern with sardines or other oily fish
Raw fish is safe to feed to dogs and cats.
a. Certain types of fish (carp and herring) contain thiaminase
i. Destroys thiamin and may cause a thiamin deficiency
b. Thiamin deficiency
i. Clinical signs
1. Anorexia, weight loss, depression
2. Neurological signs of ataxia, paresis, convulsive seizures
3. Severe weakness leading to death
ii. Treatment
1. Dietary correction (elimination of raw fish)
2. Thiamin therapy
a. Administration of thiamin intravenously or subcutaneously (75-100 mg) twice daily until neurological signs subside
b. Oral supplementation for several months following
c. Most clinical signs will decrease within several days
d. May never make a full recovery if severe neurological damage occurred
c. Thiaminase is heat-labile
i. Denatured by normal cooking temperatures
ii. Only a concern with uncooked fish
Cats should be fed high amounts of liver.
a. Risk of developing vitamin A toxicosis
i. Dogs relatively resistant
b. Deforming cervical spondylosis
i. Bony outgrowths in joints of cervical vertebrae and forelegs
ii. Clinical signs
1. Anorexia and weight loss
2. Increased lethargy and reluctance to move
3. Persistent lameness in one or both front legs
4. Decreased ability to self-groom
5. Decreased ventriflexion of the head
6. Posture changes by adopting a marsupial-like sitting position
iii. Develops slowly over time
iv. Treatment
1. Remove source of excess vitamin A
2. Resolution of skeletal lesions may never be complete
There is no concern giving cats milk.
a. Excessive intake may cause diarrhea
b. Milk contains the simple sugar lactose
c. Lactose requires breakdown in the intestine by lactase
d. Lactase activity declines with age
e. Inability to completely digest milk
f. Causes digestive upset and diarrhea
Supplementation of raw eggs
a. Some owners believe that feeding eggs improves hair quality and adds luster and shine to their dog’s coat
b. Others wish to increase or improve protein in their dog’s diet
c. Increase food’s palatability and acceptability for some dogs and cats
d. Egg protein has one of the highest biological values of common protein sources
* Cooked egg is highly digestible and provides all essential AA
* Good source of iron, vitamin A, vitamin D, and several B vitamins
* Excellent source of essential fatty acids (~4% of fat in egg yolk = linoleic acid)
e. Egg white (albumen) contains several inhibitory substances that alter the metabolism of specific nutrients
1. Avidin and Biotin
* Avidin protein
o Secretory product of the hen’s oviduct
o Deposited in albumen portion of egg
o Combines with dietary biotin in the intestine and prevents absorption
* Yolk contains large quantities of biotin
* Cooking denatures avidin and destroys its biotin binding ability
* Signs of biotin deficiency in dogs and cats = dermatitis, loss of hair, poor growth
2. Egg white trypsin inhibitor
* Feeding raw egg whites can result in diarrhea and weight loss in dogs
a. Same effect in dried (uncooked) egg white
b. Utilization of raw egg white only 58.6%
* Trypsin inhibitor proteins in egg whites reduce protein digestibility
* Cooking denatures trypsin inhibitor
f. If owners wish to add egg to their pet’s food – limit to just one or two cooked eggs per week for a medium or large dog
Chocolate – Theobromine
a. Toxic to dogs when consumed in large quantities – can be life threatening
b. Acts as a smooth muscle relaxant, coronary artery dilator, diuretic, and cardiac stimulant
c. Dogs are sensitive to physiological effects
* Lower rate of theobromine metabolism – longer half-life in bloodstream and tissues
* Half-life in plasma of dogs = 17.5 hours
* Half-life in humans = 6 hours
* Half-life in rats = 3 hours
d. Toxicity in dogs
* Vomiting, diarrhea, panting, restlessness, increased urination or urinary incontinence, and muscle tremors
* Signs occur ~4-5 hours after consumption
* Seizures signifies poor prognosis in most cases and often results in death
* Treated by inducing vomiting as soon as possible
o Activated charcoal “shake” given by gastric lavage may decrease quantity absorbed in bloodstream
o No specific systemic antidote
e. Toxic dose of theobromine ≥ 90 – 100 mg/kg of body weight
* Dependent on sensitivity to theobromine and presence of other foods in GI tract at the time of ingestion
f. Chocolate products vary in theobromine concentrations
* Baking chocolate = 1.22% theobromine
a. 1 oz square = 346 mg of theobromine
b. 3 oz would result in a potentially toxic dose for a 25 lb dog
* Cocoa powder = 1.89% theobromine
a. Highest theobromine content of all commonly consumed chocolate products
* Addition of sugar, cocoa butter, and milk solids to baking chocolate to produce sweet chocolates dilute theobromine content
a. Semi-sweet chocolate = 0.463%
i. 0.5 lb would result in a potentially toxic dose for a 25 lb dog
b. Milk chocolate = 0.153%
i. 1.5 lb would result in a potentially toxic dose for a 25 lb dog
g. Dogs enjoy sweet flavors – will overconsume chocolate
Feeding brewer’s yeast or thiamin repels fleas
a. Early studies reported supplementation of thiamin was beneficial for humans (decreased mosquito bites and dermatological reactions and helped children with severe flea infestations)
* Studies were not well controlled
* Several studies with humans since have failed to show any effect of thiamin supplementation on insect infestations
b. Neither brewer’s yeast or thiamin repelled fleas or mosquitoes in studies conducted in dogs
Feeding garlic or onion repels fleas
a. No effect on fleas
b. Make pet’s breath smell
c. Feeding large amounts of onion or garlic to dogs or cats can be toxic
d. Excess consumption of onions results in formation of Heinz bodies on circulating red blood cells – results in the development of hemolytic anemia
* Severe cases, anemia can be fatal
* Toxic compound = N-propyl disulfide
* Signs = diarrhea, vomiting, depression, fever, and dark-colored urine
* Vomiting and diarrhea may be immediate
* Remaining signs usually appear 1-4 days following ingestion
e. Excessive amounts of garlic can cause oxidative damage to red blood cells leading to Heinz body formation and eccentrocytosis
* Eccentrocytes = red blood cells that contain abnormal hemoglobin
* When severe can result in anemia
f. If onion or garlic toxicity is suspected, seek veterinary care immediately
g. Many dogs love the taste of onions and garlic – may overconsume
1. Diet causes “hot spots” (acute moist dermatitis)
a. Frequently occurs during warm months of the year
b. Lesions are inflamed and feel hot to the touch
c. Most seen in breeds of dogs that have very dense, heavy coats
* May be related to poor ventilation of skin or inadequate grooming
d. Lesions can develop within a few hours
* First noticed as a patch of missing hair
* Round, red, moist area that is painful to touch rapidly develops
* Yellowish center surrounded by reddened ring of inflammation
* Self-trauma – biting and scratching of affected area (itchy)
* If not treated, spots may spread
e. Any factor the causes irritation and self-trauma can lead to acute moist dermatitis
* Allergic reactions, external parasites, skin infections, unhealed injury, or improper grooming
f. Believed by some pet owners that a diet too “rich” or too high in protein causes hot spots
* No evidence of relationship
* Diet may play a role if pet has adverse reaction or an essential fatty acid deficiency
Coprophagy (stool eating) is caused by a nutrient deficiency
a. Coprophagy is common in dogs, rarely seen in cats
b. Due to dog’s evolutionary history
* Wolf is a social predator but also a food scavenger
* Will eat carcasses killed by natural causes or other predators, various types of vegetation and fruits, and garbage
c. Eating feces is scavenging behavior – observed in both pet dogs and captive/wild wolves
d. Ingestion of feces may supplement certain vitamins but no evidence that dogs (or wolves) selectivity consume feces in attempt to obtain nutrients
e. Female dogs and wolves routinely consume the feces of their puppies
* Behavior may continue after puppies are whelped
* Can be socially facilitated between dogs within the same household
The occurrence of “red coat” in dogs
a. Refers to a perceived change in coat color from almost any normal base color to a red or reddish brown
b. Beet pulp thought to be potential cause due to perception that beet pulp is red
* Beet pulp included in pet foods is derived from sugar beets (not red beets) and is light brown
* No evidence suggesting connection
c. Nondietary causes
* Aging
* Sunlight exposure
* Topically applied dips or shampoos that contain certain insecticides
* Frequent shampooing and blow drying
* Porphyrin staining
a. Found in tears and saliva of dogs
b. Normal end product of hemoglobin metabolism
c. Turns red upon exposure to sunlight
d. Reddish staining seen around eyes of some dog breeds
e. Reddish staining can also be seen with excessive grooming/licking
d. Frank nutrient deficiencies (copper, zinc, phenylalanine, tyrosine)
* Other clinical signs present
* Rare if fed commercial diets
Vitamin C supplementation prevents skeletal disease in growing dogs
a. Early report compared the development of hypertrophic osteodystrophy (HOD) in young dogs with the bone abnormalities associated with scurvy (vitamin C deficiency) in humans
b. Crucial difference had been overlooked
* HOD = osteopetrosis
a. Excess bone deposition and stunted bone resorption
* Scurvy = osteoporosis
a. Demineralization of bone caused by impaired collagen formation by osteoblasts in the developing skeleton
c. Supplemental ascorbic acid has no preventive effect
d. May exacerbate the development of certain skeletal lesions in growing dogs
* Study reported higher levels of serum calcium in supplemented puppies
e. Association to HOD was expanded to other developmental bone disorders such as canine hip dysplasia and osteochondrosis
* Many began to supplement growing dogs’ diets
* No evidence to support claim
f. Excess is excreted in urine as oxalate
* High concentration of oxalate can contribute to the formation of calcium oxalate uroliths in urinary tract
