Haematology by Tom Meulman (Australia)
Haemoglobin (Hb) - Preferred Range - 20.0 to 21.5 g/lHaemoglobin is the is the iron-containing pigment of the red blood cells. It’s function is to take up oxygen from the lungs and carry it throughout the body.
Haemoglobin and Red Blood Cells are manufactured in the bone marrow of the long bones. Because iron is the main component needed for haemoglobin production, a shortage of iron will cause the bone marrow to produce Red Blood Cells that are smaller and do not contain sufficient haemoglobin. The end result is a greyhound that is incapable of running it’s full race distance without causing stress to other body functions due to lack of oxygen.
Racing greyhounds with Haemoglobin levels below 20.0 g/l will in most instances require iron injections to correct this deficiency.
Red Blood Cell count (Erythrocytes) - Preferred Range - 8.50 to 9.50 X 10/lRed Blood Cells are the vehicles that carry Haemoglobin throughout the body. Red Blood Cells also have some secondary functions, as in the body’s immune response, and in releasing several substances that dilate blood vessels when required to improve oxygen delivery.
Red Blood Cells are manufactured in the bone marrow of the long bones and in rare instances where excessive running increases inflammation in the long bones of the limbs, this may reduce Haemoglobin and Red Blood Cell Production.
Red Blood Cell production is controlled by Erythropoietin (EPO) this is a hormone that is primarily produced in the kidneys, therefore kidney disease and kidney damage will cause Anaemia.
Racing greyhounds with a Red Blood Cell count below 8.50 X 10/l will require B12 and Folic Acid injections to correct this deficiency.
Hct (Haematocrit) or PCV (Packed Cell Volume) - Preferred Range 58% to 62%This measures the percentage of solids in the blood, namely the Red and White blood cells, as compared to the quantity of blood plasma. It is therefore extremely important to consider the state of hydration of the greyhound when considering whether or not a particular percentage is satisfactory.
If this particular test is done without other blood perimeters being tested for, the hydration of the greyhound should be evaluated by carefully checking skin tone, as this gives some idea of the state of hydration.
If the skin is comfortable to lift and springs back fast both over the saddle and the coupling area, the true PCV is as per test result.
However if the skin springs back OK over the saddle but is slow to return over the coupling area, the PCV could be as much as 2% lower if the greyhound was fully hydrated. If the skin is also slow to return above the saddle area the PCV could be as much as 4% lower if the greyhound was fully hydrated.
In other words a PCV test result of 58% in a severely dehydrated greyhound means that the true PCV is likely to be around 54% and indicates the greyhound is anaemic. At the same time a PCV test result of 66% in a severely dehydrated greyhound, indicates that the PCV would be within the preferred range once the dehydration has been corrected.
If the Hct/PCV test result is part of a full analytical profile there are other results that will provide information on the state of hydration.
Further to the above; if the skin of the greyhound is difficult to grab hold of and is tight to lift up, immediate Veterinary assistance should be sought as the greyhound is severely stressed and will most likely require intravenous fluids.
MCV (Mean Cell Volume) - Preferred Range 68 to 75 flThis is an estimate of the size of Red Blood Cells, and provides an indication of the cause of anaemia. Immature red blood cells being larger than older ones.
A MCV below 68 fl indicates anaemia due to iron deficiency. If however the Haemoglobin count is within the preferred range it may indicate Red Blood Cell destruction, blood loss due to internal bleeding, or a heavy load of blood sucking intestinal worms.
A MCV above 75 fl indicates anaemia due to a B12/Folic Acid deficiency, or an inadequate diet.
MCH (Mean Cell Haemoglobin) - Preferred Range 22 to 25 pgThis is a calculation of the haemoglobin inside the average Red Blood Cell.
MCHC (Mean Cell Haemoglobin Concentration) - Preferred Range 34 to 37 g/dlThis is a calculation of the average haemoglobin concentration in a given volume of packed Red Blood Cells.
Both these test results provide further information on the type and cause of anaemia.
The MCH may be low in types of anaemia where the red blood cells are abnormally small, or high in other types of anaemia where the red blood cells are enlarged (for example, as a result of folic acid or vitamin B12 deficiency).
The MCHC is low in iron deficiency, blood loss, and anaemias caused by infections in the liver or kidneys.
Differential
White Cell Count (Leucocyte) - Preferred Range 3.5 to 5.5 10/9/lA white cell count estimates the total number of white blood cells per litre of blood. This count may be high due to an infection, tissue damage, severe inflammation, or severe stress.
The count may be low in some viral infections, liver disease or a depressed immune system.
A differential count provides an estimate of the numbers of the main types of white blood cells.
These are: neutrophils, lymphocytes, monocytes, eosinophils, and basophils, and each of these has a specific role in protecting the body.
Neutrophils and monocytes protect the body against bacteria.
Lymphocytes are involved in the immune process, producing antibodies against viruses.
Eosinophils kill parasites and are involved in allergic responses. High numbers of eosinophils may be associated with worm infestations or exposure to substances that cause allergic reactions.
Basophils also take part in allergic responses and increased basophil production may be also associated with a viral infection.
Neutrophils - Preferred Range 3.0 to 4.5
Lymphocytes - Preferred Range 0.8 to 1.9As a general rule when Neutrophils increase in numbers it is due to a bacterial infection, and when Lymphocytes increase it is due to a viral infection. However it is also important to look at the quantitative relationship between the these two numbers instead of just looking at each individual level coming within the preferred range.
In other words a situation can exist where for instance the Lymphocytes count is 0.8 and the Neutrophils is 4.5, and at 4.5 is within the preferred range, however with a Lymphocytes count of 0.8 the Neutrophils count should not be much higher than 3.0, and therefore a low grade bacterial infection should be suspected. The same applies if the situation was reversed between Neutrophils and Lymphocytes counts, and a low grade viral infection should be suspected.
Monocytes - Preferred Range 0.1 to 0.6Monocytes assist Neutrophils in fighting bacterial infections and eliminating small particles of foreign matter.
Eosinophils - Preferred Range 0.1 to 0.5Eosinophils kill parasites and are involved in allergic responses. Increases due to worm infestations or exposure to substances that cause allergic reactions.
Basophils - Preferred Range 0.0 to 0.1Increase due to inflammation and/or allergic reaction, and some viral infections.
Band Neutrophils - preferred Range 0.0 to 1.0Increase indicates a recent or acute infection.
Biochemistry
Alk Phos or ALP (Alkaline Phosphatase) - Preferred Range 10 to 80 u/lThis enzyme is mainly produced in the bile ducts of liver and therefore high levels are generally associated with liver bile function problems. Smaller amounts are also produced by bone and elevated levels can also indicate rickets in young pups. Increased levels may also indicate problems with the Parathyroid as this regulates the levels of calcium and bone growth.
ALT (Alanine Transaminase) - Preferred Range 5 to 60 u/lALT is an enzyme produced in the liver cells (hepatocytes). ALT level in the blood is increased when hepatocytes are damaged or die.
The level of ALT in the blood provides to some degree a picture of current liver cell damage, but does not provide an accurate picture of remaining liver function.
When ALT blood levels are high it is extremely important to find out why the liver is damaging, and to provide support for the liver such as Livatone tablets and L-Carnitine injections.
What causes liver damage?
The main causes of liver damage are a bacterial or viral infection, or anything that causes liver inflammation. Such as severe bruising due to race collisions, toxic substances in the food supply, indiscriminate use of flea killing chemicals, heat stroke and inflammation of the pancreas.
The liver can also be damaged due to a reduced supply of oxygen killing liver cells. This can occur when a greyhound with anaemia is kept in hard work without repairing the anaemia, or a greyhound is consistently raced over a too long a distance than it is capable of running comfortably.
AST (Aspartate Transaminase) - Preferred Range 10 to 40 u/lAST is found in various tissue, such as the liver, kidneys, heart, brain, and muscle tissue. It is released into the blood when any of these tissues is damaged. It is therefore not a specific indicator of liver damage, the levels in the blood can also increase due to muscle, kidney, or heart damage.
CPK (Creatine phosphokinase) or CK (Creatine Kinase) - Preferred Range 40 to 300 u/lCPK is primarily found in muscle tissue, including heart muscle, and leaks into the blood when muscle cells are damaged. Therefore elevated levels generally indicate a muscle injury in one or more muscles, or is caused by a too hard or a too far a run, resulting in general muscle damage throughout the skeletal muscle structure.
Greyhounds with high CPK/CK levels need to be thoroughly checked for muscle injuries, and if none are found, should have a short spell and then be worked more gently with sufficient recovery time between runs until fully fit again.
Total Protein - Preferred Range 45 to 60 g/lFirstly, a high protein diet does not cause high levels of protein in the blood.
The two main proteins in the blood are Albumin and Globulin, and also a small amount of Fibrinogen which is essential in the clotting of blood.
Excessively high levels of total protein in the blood generally indicates an illness such as a chronic infection, liver dysfunction or severe dehydration.
Excessively low levels of total protein in the blood also indicates illnesses such as severe kidney disease, liver disease, or severe malnutrition.
Albumin - Preferred Range 24 to 34 g/lAlbumin is manufactured in the liver from dietary proteins. Albumin assists in maintaining the osmotic pressure of plasma, and transports fatty acids, steroid hormones, including the thyroid hormone thyroxine, and acts as a transport for many drugs.
High levels of Albumin are seen in severe dehydration, in greyhounds suffering hyperadrenocorticism (hyperactive adrenal gland), and in greyhounds suffering severe stress.
Low levels of Albumin may be caused by severe liver and/or kidney disease (Nephritis), severe protein malnutrition, or due to extremely low Thyroid function.
Globulin - Preferred Range 22 to 32 g/lGlobulins are proteins who’s major portion are Gamma Globulins, these are antibodies essential to the immune system, other Globulins act as carrier/transport proteins.
The Globulin level may be elevated due to chronic infections, both viral and bacterial, in some parasite infections, and in liver disease.
The Globulin level may be reduced due to Nephritis (A condition where kidney function is so compromised that the kidneys no longer filter proteins from the blood and these leak into the urine), liver disease, and in acute Hemolytic Anaemia. (Hemolytic Anaemia is anaemia caused by the rapid destruction of Red Blood Cells.)
A/G Ratio - Preferred Range 1.2 to 1.6 g/lThe A/G ratio is the calculated ratio between Albumin and Globulin in the blood, and may be elevated due to low Globulin levels and a depressed immune system, and low in liver disorders.
Treatment for a depressed immune system.4 ml (50 mg) Levamisole, twice daily for 14 days
1 Glutamine Complex (400 mg) tablet given twice daily on an empty stomach, for 14 days
1 level teaspoon of Vitamin C powder (Calcium Ascorbate) per day for 14 days
1/4 teaspoon of Vitamin E powder per day for 14 days
To build and maintain a healthy immune system a wide range of protein from various sources in the diet are also extremely important. The amino acids required for a healthy immune system are mainly available from egg and milk protein.
Electrolytic Ions Essential for Normal Muscle Function (Electrolytes)
Phosphate - Preferred Range 0.95 to 2.10 mmol/lPhosphate is an electrolytic ion that contains phosphorus.
Phosphorus is essential for bone strength and repair, and is also required to produce ATP (Adenosine Triphosphate), which is used by cells to transport chemical energy, and as such is essential for efficient muscle contractions.
Low Phosphate blood levels can occur due to excessive use of diuretics (So called kidney flushes that are unfortunately popular with many trainers for use after a hard run), and due to respiratory alkalosis as a result of a distressed greyhound hyperventilating for several hours while waiting for a race.
High Phosphate blood levels may occur as a result of excessive dietary intake, reduced kidney function, rhabdomyolysis caused by excessive exercise, or a deficiency in calcium or magnesium.
Calcium (Ca) - Preferred Range 2.4 to 3.0 mmol/lCalcium is one of the most important minerals in the body as it is not only essential for bone strength and bone repair, 50% of the calcium is in the blood in the form of an electrolytic ion that is essential to muscle function and contraction.
The level of calcium in the blood is regulated by the Parathyroid, small glands attached to the Thyroid. When blood calcium is low, within 1 to 2 hours calcium is leached from the bones to restore blood calcium levels, and when blood calcium is high, excess calcium is stored in the bones or passed out via the kidneys and faeces.
It is also essential that calcium is provided in the daily diet as calcium is lost from the body each day, this loss is aggravated by Metabolic Acidosis as this increases loss of calcium via the kidneys.
The most common reason for high or low calcium levels in the blood is due to malfunction of the Parathyroid glands. Care must be taken not to overdose when providing a Thyroid hormone supplement as this can affect the function of the Parathyroid.
For a more detailed description of Calcium function see HERE
Magnesium (Mg) - Preferred Level 0.8 to 1.3 mmol/lMagnesium is an important electrolytic ion essential for normal muscle function as it is required to move the electrolytic ions of Potassium and Sodium in and out of cells during muscle contractions.
Only a small amount of Magnesium is present in the blood, the major portion being contained within the bone structure and muscle cells. The body regulates Magnesium by shifting it in or out of cells.
High magnesium levels may be caused by excessive muscle cell damage releasing Magnesium from the cells to the blood plasma, or by poor kidney function.
The most common cause of low blood Magnesium is insufficient Magnesium in the diet.
Sodium (Na) - Preferred Level 140 to 155 mmol/lSodium is an essential electrolytic ion that functions with other electrolytes such as potassium, calcium, and magnesium in muscle contractions.
The other essential function of Sodium is to regulate the fluid balance of the body.
The kidneys maintain the Sodium levels of the blood in a very narrow range despite variations of Sodium intake in the diet, so variations outside the preferred level are usually caused by problems with kidney function.
Excessive Sodium loss can result from the indiscriminate use of diuretics (kidney flushes) stopping the kidneys from functioning as required, vomiting and diarrhoea.
Low Sodium blood levels causes dehydration.
For a more detailed description of Sodium function see HERE
Potassium (K) - Preferred Level 3.8 to 5.8 mmol/lPotassium is both an essential electrolytic ion in muscle function and a mineral.
It assist in maintaining fluid balance inside cells, and in maintaining the electrolyte balance of the body. It is also required for normal heart function and rhythm and for maintain electrical signals in nerves.
About 98% of the Potassium in the body is kept within the muscle cells, with only 2% in the blood.
Because Potassium is lost from the body continually even when Potassium levels are already low, it is essential that the diet contains sufficient Potassium to replace the losses.
High blood Potassium levels may be caused by muscle cell damage releasing Potassium into the blood, and by reduced kidney function.
The most common causes of low blood Potassium are insufficient Potassium in the diet, excessive use of diuretics, or hyperadrenocorticism (hyperactive adrenal gland) as this increases the production of the hormone Aldosterone which causes the kidneys to retain water and sodium, and increase loss of Potassium.
For a more detailed description of Potassium function see HERE
Blood pH
Chloride (Cl) - Preferred Range 100 to 115 mmol/lHigh or low levels of this electrolyte generally indicate a fluid or electrolyte imbalance, and because the kidneys control the level of Chloride in the blood, therefore a major variation in Chloride levels is often related to kidney function.
Possible causes of high Chloride level are; reduced kidney function, dehydration, excessive salt intake (Sodium Chloride), or due to a distressed greyhound hyperventilating for several hours while waiting for a race (respiratory alkalosis).
Possible causes of low Chloride level are; low blood sodium, or excessive use of diuretics.
CO2 (Carbon Dioxide) Preferred Level 24 to 28 mmol/lBecause most of the CO2 is in the form of bicarbonate (HCO3-). Therefore the CO2 blood test is really a measure of the blood bicarbonate blood level.
Possible causes of low CO2 are; severe stress, metabolic acidosis, and kidney disease.
Common cause of high CO2 is excessive dosing with bicarbonate of soda.
Waste Products
Urea (BUN) - Preferred Level 3.5 to 10.0 mmol/lThis tests the amount of Nitrogen in the blood in the form of Urea. Urea is a waste product produced by the liver when processing protein, and is removed from the body by the kidneys. Therefore this test is an assessment of kidney function.
However the test results should be looked at in conjunction with the test for Creatinine in the blood, as a high level of Urea with normal Creatinine levels indicates dehydration and/or a diet excessively high in protein placing kidney function under stress.
Blood Urea Nitrogen levels also increase due to internal bleeding, or a high level of infestation by blood sucking intestinal worms such as hookworm.
Low levels of Urea have little significance unless the the blood ALT level is extremely high, as this then indicates an inability of the liver to process protein.
Creatinine - Preferred Level 80 to 160 umol/lCreatinine is a waste product produced from the use of Creatine by muscle tissue, and is removed from the body by the kidneys.
Increased levels are also seen when the CK (Creatine Kinase) level in the blood is high due to a muscle injury or Rhabdomyolysis (generalised muscle cell destruction), and in dehydration.
While this test is often considered an assessment of kidney function, it would require two or more blood tests showing very high levels Creatinine before a diagnoses of severe kidney damage could be made.
Energy
Serum Glucose (blood sugar) - Preferred Level 4.2 to 6.8 mmol/lGlucose is the primary energy source for body cells.
Glucose is transported from the intestines and liver to body cells via the bloodstream, and is moved into the cells by insulin which is produced by the body in the pancreas.
Increased levels may occur due to excitement and/or stress, or may be low due to not having eaten within the past 8 hours.
Adding Glucose to the diet will only temporarily increase blood sugar, as levels are kept to close tolerances and the liver will stop producing Glucose causing the levels to drop significantly after about two hours until the liver starts producing Glucose again.
Fatty Acids
Cholesterol - Preferred Level 3.2 to 6.2Cholesterol is a steroid of fat that is produced by the liver, and is an essential component required to manufacture cell membranes, bile acids, steroid hormones and Vitamin D.
Cholesterol is primarily manufactured using animal fats in the diet, and the addition of excessive amounts of plant oils to the diet can reduce the production of Cholesterol.
Other
Bilirubin - preferred Level 2 to 12 umol/lOld or damaged Red Blood Cells are disposed of in the spleen, This releases the Haemoglobin which in turn is broken down by the spleen into the globin part which is then turned back into Amino acids, and the Heme part is turned into Bilirubin.
At this stage the Bilirubin is not water soluble, and it is bound to Albumin and sent to the liver. The liver processes the Bilirubin and turns it into a water soluble state, and then transfers it into the gallbladder for use by the digestive system to break down fatty acids in the diet.
It is only when liver function is compromised, that excess Bilirubin in it’s water soluble form is returned to the blood to be disposed of by the kidneys.
Due to the ability of the kidneys of canines to dispose of Bilirubin in the urine, high Bilirubin levels in the blood generally indicates problems with both the liver and the kidneys.
When the kidneys are functioning properly, and liver damage is suspected, a test for Bilirubin in the urine may be indicated.
Iron - Preferred Level 20 to 50 nmol/lIron is essential for the production of haemoglobin, and to avoid Iron-deficiency anaemias.
Low levels of Iron will require supplementation or Iron injections. Excessively high levels of Iron (Ferritin) are extremely rare in greyhounds as it takes many years for Iron to build up in the organs and cause ill health. However excessive supplementation in a greyhound with poor kidney function may cause toxicity and liver damage.
****************************************************************************************************Please keep in mind when assessing an Analytical Blood Profile
Analytical blood profiles should never be looked at in isolation, but should be used as a source of additional information to add to the information gained from a thorough examination of the greyhound who’s health is being assessed.
This examination should take note of:
The state of hydration in regard to skin tone.
The general condition of the greyhound in regard to an healthy weight and muscle condition.
The general condition of the greyhound in regard to vitality and general demeanour.
Recent levels of stress, such as a run behind the lure within the past five days.
The general recovery rate of the greyhound after stressful exercise.
A thorough examination for muscle injuries, and for general increased pain levels.
And most important of all a re-examination of all that has occurred to the greyhound in the previous 4 to 6 weeks that may have led to, or contributed to the greyhounds current condition.
Cheers,
Dr.Tom Meulman
Here is what a blood picture looks like of a dog a day after a race. Same dog showed perfectly normal values 4 days after a race.