Nutrition and Health: Feeding for Disease

Question 1

What is feeding for disease

Answer 1

• Feeding for specific illness in companion animals
• Diet has been shown to be very helpful in helping to control specific diseases in dogs and cats.
• In certain circumstances, dietary control is the only modification required to achieve significant clinical improvement.

Question 2

Renal function and diet

• how does renal failure relate to diet
• If kidney function is compromised, what are the consequences?

Answer 2

• Renal failure is common in older animals and also seen in several medical conditions at any age.
• Control of diet can be very significant when trying to treat or manage a medical condition that involves a degree of renal compromise.
• Nitrogenous waste products from protein are excreted from the kidney.
• Waste products are not excreted efficiently which leads to a build up in the bloodstream which can cause a variety of clinical signs.

Question 3

renal function and diet

- What are the waste products, where do they come from

Answer 3

• excreted by the kidney are urea and creatinine.
• Urea is the important waste product when considering diet.
• When protein is broken down, ammonia is produced which is very toxic to the animal’ body.
• The body uses the urea cycle to convert ammonia to urea (less toxic) and the urea is excreted by the kidneys.
• If the kidneys are not filtering appropriately urea builds up in the blood stream and leads to clinical signs.

Question 4

renal function and diet

• clinical signs
• how can we control

Answer 4

• depression
• weight loss;
• inappetence or anorexia;
• vomiting;
• polyuria and polydipsia;
• gingivitis with ulceration;
• pale mucous membranes (non-regenerative anaemia);
• uraemic breath;
• reduction in kidney size and shape
• dehydration

~ involves supportive therapy ~ management
~ anabolic steroids which may improve the animal’s condition but by the time of diagnosis this may not be possible.
~ diet - manage clinical signs

Question 5

renal problem: Urea and creatinine build up in bloodstream (how to solve with diet)

Answer 5

• Reduce urea build up by -
• Moderately restricting protein content of food.
• Providing high quality protein only.
  ~ If protein is restricted too far, muscle loss may be exacerbated.
  ~ If blood urea levels remain high, diet may be further restricted.

Question 6

Renal problem: protein loss through kidney increases (proteinurea)

problem: appetite decreased significantly

Answer 6

Use high energy density diet using non-protein sources (fat).

give highly palatable diet

Question 7

Problem: weight loss occurs

Answer 7

Utilise high energy density diet using non-protein sources such as fat

Question 8

Problem - Phosphorus retention increases

Answer 8

• Restrict phosphorous content of diet.
• Restricted phosphorus content thought to be vital in treatment and prevention of further deterioration.
• Phosphate binders may also be used.

Question 9

Problem - Blood pressure may rise especially in cats (unless dehydration is present)

Answer 9

moderately restrict sodium content

Question 10

Problem - Thirst increases as extra water is lost from the kidney - water-soluble vitamins are lost.

Answer 10

Enhance levels of B-complex vitamins.

Question 11

Problem - Potassium loss via the urine can be significant.

Answer 11

Potassium may be supplemented.

Question 12

Problem - Calcium levels may rise.

Answer 12

Acidaemia increases bone resorption to provide buffers, and calcium comes with it.

Use non-acidifying diet.

Question 13

Obesity

- about

Answer 13

• calories ingested more than calories expended
• weightloss more dependant on profferional /owner interaction than on the diet chosen
• owner compliance can be low

Question 14

some aspects of using obesity diets

- benefits

Answer 14

• Diets can offer the following benefits
  ~ Reduced calorie density of diet (fat and CHO).
  ~ Increased water or fibre to prevent hunger.
  ~ Increased protein.

Don’t forget that purely decreasing the quantity of a normal diet will reduce not just the energy but also the essential nutrients.

Question 15

some aspects of using obesity diets
- realistic % body loss a week
- difference between dogs and cats 
- drugs available
-

Answer 15

• Realistic weight loss is 1% of bodyweight per week.
• Palatability is a problem (or an advantage!)
• Can be ruthless with dogs, but overweight cats must not be starved for more than 2 days.
• Drugs are available such as Slentrol and Yarvitan? Issues?
• home-cooked varied diet where the owner has previously fed a home- made diet as they are unlikely to comply with a prescription diet.
• All owners should be treated as an individual- one plan will not suit everyone!

(compare obesity to normal diets, nutrition)

Question 16

Hepatic disease

• about
• what it can cause

Answer 16

• When an animal is suffering from liver disease the metabolic reactions that occur in the liver are not fully efficient and so compromise of detoxification processes can lead to a build up of toxins.
• reduced ability to convert ammonia to urea leading to “hepatic encephalopathy”
• Reduced protein production can lead to oedema of tissues and ascites
• Gluconeogenesis may be impaired
• Hepatic lipidosis is a specific condition, severely affecting liver function

Question 17

hepatic problem: ammonia to urea conversion is compromised

Answer 17

Provide a restricted but very high biologic value protein content in diet.

Provide soluble fibre in diet to trap ammonia, preventing its reabsorption from the gut.

Question 18

hepatic problem: Reduced protein production can lead to oedema of tissues and ascites

Answer 18

Lower sodium content of diet to limit water retention.

Question 19

hepatic problem: Gluconeogenesis may be impaired

Answer 19

Provide most of animal’s energy requirement with highly usable fatty acids and carbohydrate

Question 20

hepatic problem: Vitamin K production reduced potentially leading to bleeding disorders

Answer 20

supplement diet with vit K

Question 21

liver disease problem: Hepatic lipidosis can occur severely affecting liver function.

Answer 21

Provide L-carnitine to aid fat metabolism.

Question 22

liver disease problem:In some breeds copper accumulation in the liver due to a genetic defect is the cause of the disease

Answer 22

Lower copper content of the diet.

Antioxidants added to diet to protect liver cell membranes (marketed as nutraceuticals).

Question 23

Diabetes mellitus

• can it be cured
• cats type of diabetes
• how diets help

Answer 23

• can benefit and be cured with dietary control
• Most cats thought to suffer from Type II diabetes and so can potentially be cured, sometimes with dietary control alone.
• Obesity is a major contributor and so control of weight is important.
• Animals may be stabilised on their own food, but prescription diets do offer advantages

Question 24

what are we aiming for when we control diabetes mellitus

Answer 24

• A slow, controlled release of sugar into the bloodstream.
• The peak blood glucose to match the peak insulin action.
• To never have glucose levels so high that they contribute to further deterioration in insulin production and effect.
• Often we also need to promote further weight loss

Question 25

What are diabetes diets composed with and when and how much to feed

Answer 25

• Low calorie to encourage weight loss.
• Using complex carbohydrates to slow release of sugar into the bloodstream.
• Increased in fibre
  ~ satisfy appetite
  ~ reduce calorie density
  ~ slow release of sugar into the bloodstream.
• Low carbohydrate and high protein encourages gluconeogenesis = provides a more reliable stream of blood glucose.
• Fat metabolism is encouraged and weight loss will occur.
• Fed as 1/3 am at breakfast and 2/3 at peak insulin activity for once a day insulin dosing.
• Fed as ½ am at breakfast and ½ 12 hrs later for twice daily insulin dosing.