FEEDING RABBITS

What do rabbits eat?

High quality rabbit chows, pellets, and good quality hay (such as lucerne, grass, or clover) can be used to make up a pet rabbit's diet.  For rabbits less than 1 year old, pellets and hay should be available ad libitum, which means the rabbit is free to eat as much of each as it wishes.  For animals over 1 year of age, hay, which provides fibre, should be available free choice and make up most of the diet.  Pellets or chows can be offered at approximately 1/4 cup per 2.5 kg of body weight.  Overfeeding pellets to adult rabbits is a common cause of disease. While rabbits can eat any type of hay, lucerne hay is too rich to be the only source of hay; other grass hays are preferred. Coprophagy (eating of faeces) is a common practice with rabbits.

How often should I feed my rabbit?

Rabbits should be fed daily; hay should be available at all times.

Do I need to give my rabbit vitamins?

No, rabbits do not require extra vitamins.  To help control hairballs, cat laxatives can be given daily or every few days.

Can I offer my rabbit treats?

While obesity is not a common problem with rabbits, they certainly can become overweight if fed a lot of high calorie treats. Significant problems occur if rabbits are offered sweet treats since their digestive system was never designed to cope with such high calorie food. Items such as fruits and vegetables should be offered daily.  With fruits and vegetables,

they should be thought of as a supplement (think of fruits as a treat) and not as the sole diet.  Therefore, limit their amount to no more than 20% of the diet, with vegetables making up most of this 20%.  Fresh produce is best; make sure it's thoroughly washed prior to feeding.  As with many pets, variety is the key, so offer small amounts of several items (avoid just lettuce, apples, and carrots).  Avoid lettuce and celery as they are of little nutritional value.  Anything green and leafy is loaded with vitamins and is a good supplement. 

What about water?

Fresh water is offered 24 hours a day.  If you offer your rabbit water in a bowl, make sure the rabbit does not spill it in his cage.

Anything else?

Chew toys should be available; anything suited for dogs, such as commercially available dog-chew or well-boiled meat bones, are fine.  Many owners offer their rabbits wood sticks to chew, which helps control overgrown incisors.

The Cancer Patient and Nutrition

Nutrition is not often thought of as a critical issue in cancer management, but can be an important variable that effects quality of life and survival times. In patients with cancer, particularly metastatic disease, it is not a question of curing the patient, but a question of how can the quality of life for the patient be increased.

When cancer is diagnosed in a dog, there are one of three situations:

1. Neoplasia without nutritional complications
2. Neoplasia with anorexia
3. Neoplasia with cachexia

Most patients that are diagnosed to be having neoplasia have loss of weight but the dilemma is to determine whether the weight loss is due to anorexia, or cancer cachexia. A patient that presents with anorexia requires immediate attention including administration of enteral, or possibly partial or total parental nutrition. Often in advanced neoplastic diseases there is an element of intermittent anorexia associated with chemotherapeutic treatment of the disease itself.

In general, anorexia results in weight loss primarily of adipose tissue, while patients with cachexia will lose nearly equal amounts of skeletal muscle and fat mass.

The mechanisms of cancer cachexia are complex and biochemical and hormonal stimulation of weight loss and cachexia may also occur in these conditions as well and include:

• Starvation and malnutrition.

• Impaired oral intake.

• Stomatitis, taste aversions, zinc deficiency.

• Dehydration.

• Nausea.

• Constipation.

• Bowel obstruction.

• Pain.

• Impaired gastrointestinal absorption.

• Maldigestion.

• Exocrine pancreatic insufficiency.

• Diarrhea.

• Development of ascites, pleural effusion.

• Infections.

• Heart, lung, kidney failure, hyperthyroidism.

• Prolonged deconditioning.

• Growth hormone deficiency.

The Role of Nutrition in Cancer
The demise of the patient with neoplasia is not always due to the neoplasia itself, but to the overwhelming loss of body condition.

The two major nutritional goals that need to be equally addressed in a cancer patient are:

• Inhibiting tumor growth
• Preventing or managing cachexia

A well balanced diet is important to take care of both cachexia and tumour growth. When the protein concentration in the dog food increases, the quality of the food is often better meaning that a decrease in the overall nutritional balance of the food increases the incidence of neoplasia.

Diabetes Mellitus in Dogs and Cats

What Is Diabetes Mellitus?

Diabetes mellitus is an illness caused by the body’s inability to either make or use insulin, which is a hormone produced and released by specialized cells in the pancreas. Insulin permits the body’s cells to take sugar (glucose) from the blood and use it for their metabolism and other functions. Diabetes mellitus develops when the pancreas doesn't make enough insulin or when the body’s cells are unable to use available insulin to take glucose from the blood. It is generally common in dogs and cats that are over 6 years old. It is rare in young dogs. The condition is commonly divided into two types, depending on the origin of the condition: Type 1 diabetes, sometimes called "juvenile diabetes", caused by destruction of the beta cells of the pancreas. This condition is also referred to as Insulin-Dependent diabetes, meaning exogenous insulin injections must replace the insulin the pancreas is no longer capable of producing for the body's needs. Insulin-Dependent Diabetes mellitus, or Type 1 diabetes is more common in dogs than in cats and usually there is no possibility the permanently damaged pancreatic beta cells could re-activate. 

The primary type of diabetes in cats is Type 2 Diabetes Mellitus. There is another less common form of diabetes, Diabetes insipidus, which is a condition of insufficient antidiuretic hormone or resistance to it. 

This most common form of diabetes strikes 1 in 500 dogs. The condition is treatable, and need not shorten the animal's life span or interfere with quality of life. If left untreated, the condition can lead to cataracts, increasing weakness in the legs (neuropathy), malnutrition, ketoacidosis, dehydration, and death. Diabetes mainly affects middle-aged and older dogs, but there are also juvenile cases. The typical canine diabetes patient is middle-aged, female, and overweight at diagnosis. The number of dogs diagnosed with diabetes mellitus has increased three-fold in the last thirty years 

                                                       

Illustration of a dog's pancreas. Cell-islet in the illustration refers to a pancreatic cell in the Islets of Langerhans, which contain insulin-producing beta cells and other endocrine related cells. Permanent damage to these beta cells results in Type 1, or insulin-dependent diabetes, for which exogenousinsulin replacement therapy is the only answer 

Clinical signs 

Hepatomegaly, muscle wasting.
Bacterial infections (urinary tract, respiratory tract).
Cataract , retinopathy (rare).
Peripheral neuropathy.
Glomerulosclerosis (rare).
Cutaneous xanthomata, ulcerative dermatosis.
Ketoacidosis 

• Depression. 
• Tachypnea. 
• Acute onset vomiting. 
• Abdominal pain (due to pancreatitis). 
• Abdominal distension. 
• Slow deep breathing (Kussmaul respiration). 
• Profound dehydration. 
• Smell of acetone on breath. 
• Hypothermia. 
• Slow capillary refill time. 
• Coma. 

Hyperosmolar coma 

• Weakness. 
• Lethargy. 
• Coma. 

Differential diagnosis 

Other causes of polydipsia 

• Hyperadenocorticism . 
• Renal disease . 
• Hyperosmolar diabetes mellitus . 
• Hepatic disease . 
• Neoplasia. 
• Hypercalcaemia . 
• Diabetes insipidus . 
• Psychogenic polydipsia . 

How Is Diabetes Diagnosed?

A dog is suspected to have diabetes if any suspicious clinical signs, such as increased drinking and/or urinating, have been observed. After a thorough physical examination, some tests are recommend to help confirm a diagnosis. These include:- 

CBC (complete blood count) and chemistry profile: These tests are commonly performed together during initial blood testing to provide information about the pet’s organ systems. The CBC and chemistry profile may show dehydration, an elevated blood sugar level, or other changes that can occur with diabetes. 

Urinalysis: Evaluation of a urine sample may show the presence of sugar (glucose) in the urine if a dog has diabetes. 

Fructosamine: Fructosamine is a protein in the blood that binds very securely to glucose. The fructosamine level is therefore a close estimation of the blood glucose level, but it is less likely to change due to stress and other factors that affect the blood glucose level. Additionally, the fructosamine level indicates where the blood sugar levels have been during the previous 2 to 3 weeks. In a dog with diabetes, the blood sugar levels are usually high for long periods of time, which would be reflected by an increased fructosamine level. 

How Is Diabetes Treated?

Dogs tend to have type 1 diabetes mellitus, therefore insulin injections are generally started at diagnosis and continued for the rest of the pet’s life. It is also recommended that dietary changes are made to help control the dog’s diabetes. A medication schedule for the pet should be maintained on the calendar, including the date and time that the medication needs to be administered, and to maintain accurate records. This will avoid forgetting to give insulin to the pet and allows tracking the pet’s treatment.

Dietary Control

Insulin therapy provides the mainstay of treatment for most diabetic patients but management of other factors such as diet and exercise can influence glycaemic control.

Since almost all diabetic dogs have insulin-dependent diabetes mellitus (IDDM) dietary management will not remove the requirement for insulin. The aim of dietary change is to improve glycaemic regulation. A diet must provide all the nutritional needs of patients and should minimize post-prandial fluctuation in glucose concentrations. 

The essential features of dietary management of a diabetic are that the diet should be:

• Consistent from day to day (to prevent unnecessary alterations in insulin requirement). 
• High in complex carbohydrates so that glucose is released in a steady fashion from the gut. 
• Given so that glucose absorption from the gut coincides with peak action of administered insulin. 
• Of the correct calorific value to take diabetics weight to optimal weight. 
• Fat restricted. 

There are a number of prescription diets which have been specially formulated for the management of diabetic patients. These can be particularly useful for achieving weight loss in obese patients. However most diabetic dogs can be stabilized on a carefully controlled program using their normal diet.

After treatment begins, periodic blood and urine tests are generally recommended. This helps ensure that the insulin dosage is right for the dog. The pet's weight, appetite, drinking and urination, and attitude at home can all provide useful information that helps determine if his or her diabetes is being well managed. All of these factors are considered when making recommendations for continued management.

Many dogs live active, happy lives once their diabetes is well regulated. However, insulin therapy and regular monitoring at home and by the veterinarian are necessary for the rest of the pet's life.

CARDIOMYOPATHY IN CATS

What is cardiomyopathy?

Cardiomyopathy is a term used to describe diseases of the heart muscle. In cats, at least three classes of cardiomyopathy have been described. In all cases, the heart disease may result in clinical signs of heart failure. Cardiomyopathy may be seen as a primary condition or secondary to other diseases.

What are the clinical signs seen with cardiomyopathy?

In the early stages of disease, the cat may be able to cope and hence show no signs of disease. This situation is referred to as compensated heart disease. Often the cats will alter their activity levels to those that they can cope with which makes it difficult to diagnose cardiomyopathy until it is quite advanced.

The major long-term concerns with all types of cardiomyopathy are:-

1.       Development of congestive heart failure:     Breathlessness and lethargy are the most frequently noticed signs of congestive heart failure and these result from a failure of the heart to efficiently pump blood.  Blood banks back into the blood vessels of the lungs, resulting in fluid accumulation in or around them.

2.       Thromboembolic disease:     Altered flow of blood in enlarged heart chambers predisposes to the formation of a blood clot within the chambers of the heart. This becomes organised and is known as a thrombus. If parts of the thrombus become dislodged they can travel in the bloodstream and become lodged in smaller blood vessels. These particles are called emboli and the most common place for them to lodge is at the bottom of the aorta which is the biggest artery in the body. This results in obstruction of the blood supply to the back legs which is usually very painful and the back legs become paralysed and cold to the touch. Although a minority of cats may recover completely with appropriate treatment, this is a potentially fatal complication of any cardiomyopathy. In some cats, a partial recovery which may take a long time is seen.

How is cardiomyopathy diagnosed?

Diagnosis of heart disease can be suspected on the basis of clinical signs, such as those of congestive heart failure, in addition to more specific tests such as chest x-rays. Electrocardiography (ECG) rarely provides useful information on heart conduction and size. Cardiac ultrasound scans, where available, are indispensable in distinguishing between the different types of cardiomyopathy.

Specific tests may be done in order to check that the cardiomyopathy is not secondary to some other disease. (see below).

What causes cardiomyopathy?

There are many causes of cardiomyopathy; however, in older cats thyroid disease (hyperthyroidism) may cause a type of cardiomyopathy. Other causes include dietary deficiency of taurine, an essential nutrient. This is not seen in cats fed a commercial cat food or fresh meat. Often, no cause of the cardiomyopathy is found.

How is cardiomyopathy treated?

In cases where an underlying cause of the heart disease is found, then treatment of this may result in improvement or reversal of the heart disease. Hyperthyroidism is the most treatable cause of cardiomyopathy since complete resolution of the heart disease is possible if treated early. In cases where no cause is identified, (referred to as idiopathic cardiomyopathy), and in cases where disease remains following treatment for an underlying cause then medication may be needed.

Treatment varies according to each case but may include:-

1.       Diuretics if congestive heart failure is present.

2.       Beta blockers to reduce the heart rate where this is excessive.

3.       Calcium channel blockers to help the heart muscle relax and hence help more effective filling of the heart.  These drugs are generally the most effective form of treatment and often are the only drug required (in the long term).

4.       Aspirin may be used for its effects at reducing the risk of thrombus formation and hence thrombo-embolic disease although it is being used less frequently these days for this purpose.  Dosing of asprin should always be as advised by a veterinary surgeon since aspirin may be toxic to cats.  Aspirin poisoning, which occurs if the dose or frequency of aspirin administration is too high, may cause vomiting and internal bleeding.  If your cat shows these signs, goes off their food or is sick then aspirin therapy should be stopped and you should consult your vet.

5.       ACE inhibitors - these drugs also help to control congestive heart failure.

The long-term outlook for a cat with cardiomyopathy is extremely variable depending on the cause of this disease. Cats with idiopathic cardiomyopathy may remain stable for several years and lead near-normal lives.

Does a cat with cardiomyopathy need a special diet? 

          Except in cases where taurine deficiency is suspected, no specific diet is recommended although       excessively salty foods are best avoided e.g. dry cat food and some cat treats, since these will predispose to fluid retention. This is because they can promote sodium retention, which increases the volume of fluid and therefore the volume of blood that the heart needs to pump. In some circumstances low salt diets may be recommended. This may increase the risk of congestive heart failure. Proprietary cat foods are usually adequate although special low salt diets are available and may be recommended by your veterinary surgeon in specific cases. Cat treats are often quite salty and probably should be avoided. Obese cats usually benefit from a controlled weight loss programme.

Testing for HCM?

Genetic tests are available for particular mutations which are recognised in the Maine Coon and Ragdoll breeds. However, not all cats with HCM will demonstrate these mutations. Therefore, a negative gene test does not rule out HCM (even in one of the aforementioned breeds). At present, the most accurate method for diagnosing HCM is the use of cardiac ultrasound (echocardiography). Go to Hypertrophic cardiomyopathy (HCM) in cats for more information on the gene test.