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Preface The need of a simple manual explaining the basic principles and procedures to cater the requirements of students is always desirable. Keeping this in view the practical manual in “Clinical Veterinary Medicine”, for course no. VCM-512 has been prepared strictly in accordance with the syllabi prescribed for the subject by the Veterinary Council of India. Veterinary Council of India (Minimum standards of Veterinary Education Degree Course- B.V. Sc. & A.H.) Regulations, 1993, have provided necessary curriculum and syllabus for the degree course of B.V. Sc. & A.H. It is hoped that this manual will help the under graduate students to learn the subject in an interactive and easy manner. It will also aid the teachers to impart instructions in Clinical Veterinary Medicine effectively.

The purpose of the clinical examination is to identify the clinical abnormalities that are present and the risk factors that determine the occurrence of the disease in the individual or population. The focal point of any investigation of animal disease is the making of diagnosis and the critical part in making that decision is the clinical examination of the animal or group of animals. Without a proficient clinical examination and an accurate diagnosis it is unlikely that the treatment, control, prognosis and welfare of animals will be optimized.  The level of examination set out is sufficient to enable the clinician to determine the nature of the abnormality and the system involved.

Metabolic profile testing (MPT) refers to the use of a battery of tests for the diagnosis of subclinical nutritional and metabolic disease in dairy cows on a herd basis. Typically, blood samples from 5-7 animals per production group are tested for various analytes. MPT is most useful in the diagnosis and management of periparturient disease. Specific nutrient imbalances, either deficiency or excess, in the diet of late-gestation cows have been related to increased prevalence of milk fever, hypomagnesemia, retained placentas, downer cow syndrome, mastitis, udder edema, ketosis, hepatic lipidosis, and displaced abomasums.

Examination of rumen fluid was introduced for clinical diagnosis during the 1950’s. The stomach of ruminant harbor beneficial microbes required for digestion of feed consumed. Stomach maintains an ideal environment (pH 6.8 to 7.2 and temperature 39-40°C) for growth and proliferation of these microfloras. In any of the ruminal disorder this homeostasis get upset resulting in shifting of microbial population (Gram negative to Gram positive) and formation and accumulation of toxic products of abnormal metabolism. This further leads to an array of pathologic process in the body. Hence physical, microbial and biochemical examination of rumen fluid can be considered as an important diagnostic tool for wide variety of disorders.

The main aim of blood testing is to ascertain the adequacy of each new diet in relation to the herd’s requirements, i.e. what the cows think of their rations. So blood sampling should be carried out as soon as possible after major changes in dietary constituents. But two weeks must elapse after the changes to allow the rumen to become fully adapted. The metabolic profile is based on the concept that the laboratory measurement of certain components of the blood will reflect the nutritional status of the animal with or without the manifestation of clinical abnormalities. The values of Hb, PCV, TEC, TLC, DLC and erythrocytic indices are useful indicator of health status of the animal.

Carbohydrates are constituents of all living cells. Animal as well as plant cells use carbohydrates as source of energy. Blood glucose is a useful indicator of energy metabolism and fertility status. Under certain clinical circumstances, estimation of carbohydrates becomes essential. Sugar levels (particularly glucose) in blood or urine are used as an important parameter for diagnosis of ketosis and diabetes mellitus.

The glucose is utilized in the body for immediate energy requirements. The utilization of glucose depends on the integrated activity of digestive system metabolism and endocrine system of the body. Glucose tolerance is referred as the capacity of animal to regulate elevated blood glucose on ingestion or infusion, gradually. The level of glucose that can be tolerated by an animal without producing glucosurea is indicative of tolerance. Glucose load challenges the pancreas to release insulin which in turn regulates blood glucose level. If the insulin release is adequate and target cells have healthy receptors, elevated blood glucose level return to base value within 2 hours and glucose does not appear in urine. An increased glucose tolerance means limited rise and rapid fall in blood glucose in short span than the normal rate of utilization.

Urea is the detoxification product of the ammonia derived from the deamination of amino acids. Urea is therefore the most common nitrogen-containing end product of protein catabolism. Its synthesis from ammonia occurs in the liver (via the urea cycle), and it is then excreted by the kidneys. The concentration of urea inside red cells is slightly less than in plasma due to the presence of large amounts of hemoglobin inside the cells. Whole blood urea concentration is therefore slightly less than plasma (or serum) urea. Therefore, usually serum is used instead of whole blood for the determination of urea. The familiar term BUN (blood urea nitrogen) persists in spite of the fact that it is serum urea nitrogen which is usually measured.

The levels of calcium (Ca), inorganic phosphorus (P) and magnesium (Mg) may help in early diagnosis of metabolic and deficiency disorders and for monitoring the herd health status of dairy cattle to maintain production and reproduction. Estimation of Serum calcium Calcium is present in 2 forms – inorganic and organic forms. Most of the functions of the calcium depend upon the ionized form. For estimation of serum calcium the most commonly used method is Clark and Collip method.

Sodium and potassium are the most important electrolytes of the body fluid. The sodium as sodium chloride is contained in body fluids. The potassium is also essential in body fluids and its concentration is controlled by the kidneys. The estimation of sodium-potassium balance makes an important contribution as component of metabolic profile test. Low level of Na occurs in early lactation of low grazing on summer pasture and also increasing age, depraved appetite, polydipsia and polyurea.

Total protein: (Biuret method) There are several methods of estimating protein, in food, agricultural and clinical samples, each of them varying in sensitivity and applicability. Principle Biuret method is highly specific for protein and is based on the formation of the blue peptide-copper complex in alkaline solution. It is a method of choice in the clinical laboratory because of the simplicity accuracy and precision. The major limitation of the method is its poor sensitivity for many dilute solutions. The principle of this method is that the peptide bonds in protein react with biuret reagent to give a violet colored complex known as cupric potassium biuret. The colour intensity of which is proportional to protein concentration.

Trace minerals have long been identified as essential components in the diets of domestic livestock species. Trace minerals exist in cells and tissues of the animal body in a variety of chemical combinations, and in characteristic concentrations, depending on the trace mineral consumed and the tissue in which it is metabolized. Concentrations of trace minerals must be maintained within narrow limits if the functional and structural integrity of the tissue is to be maintained and the growth, health, and productivity of the animal are to remain unimpaired. Minerals are as vital to cattle as grass, water or air.

The concentration of essential elements must be maintained within quite narrow limits if the growth, health and productivity of the animal are to be maintained. Soil-plant-animal relationship is based on micro-mineral profile in animal blood, plant (fodder) and the soil is of paramount importance to identify dietary requirements of animals maintained under different husbandry practices of various agro-climatic zones. The soil occupies a strategic position in the chain of nutrition flow to plant, animal and eventually to man. The soil is the principal source of trace elements entering the food chain. The influence of the chemical composition of soil on the trace element contents of pant is well known.

Increased ketone bodies level in blood, known as ketonemia and condition is ketosis. The disease respond readily to treatment with glucogenic substances which can be one of the test therapy to differentiate this condition from milk fever and hypomagnesemia. The efficacy of this therapy can be estimates through estimation. Collection of blood samples Collection of blood sample is already discussed in exercise no. 4.

The daily nutrient requirements of animals varies for various stages of life i.e. maintenance ration, growing, working, pregnant, lactating, dry and diseased animals ration. Maintenance ration contains the vitamins and mineral only for life without any other production, while during pregnancy and lactation their requirements changed drastically from the maintenance ration. If not supply the standard amount of vitamins and minerals during these stages may disturb the metabolism and ultimately cause the production or metabolic disease. Therefore, the proper and sufficient (as per standard requirements) supplementation of vitamins and minerals can help in the prevention and control of production diseases in livestock.

Transfusion therapy is basically an attempt to replace blood or its components when the life is threatened. Blood transfusion plays a life saving role in general mostly to shorten the recovery time during any severe blood loss conditions arising due to accidents, major surgical interference, haemoprotozoan diseases especially in canines during anaemic conditions due to sever helminthic infestions, tick infectation, haemophilia etc. In livestock, diversity of blood and lack of commercially available blood typing reagents, make blood group matching and typing difficult, which results in reduced importance in veterinary practice. Blood or individual blood component is to be transferred during the following conditions-

Cerebrospinal fluid is found in the ventricles, cistern of brain, canal of spinal cord and in space between piamater and arachnoid. The main source of CSF is choroids plexus in the ventricles of brain. CSF is derived from the blood plasma and therefore, it has qualitatively the same composition. But the discrepancies between the ionic concentrations in cerebrospinal fluid and blood plasma indicate that the fluid is not a simple filtrate but a product of active secretary mechanism. Functionally, CSF protects and nourishes the parenchyma and maintains homeostasis. Diagnosis of diseases of CNS posses a challenge to the clinician and confirmation of tentative diagnosis based on clinical manifestations requires cytological and biochemical examination of CSF. Removal and laboratory examination of CSF are indicated whenever there is clinical evidence suggesting CNS disease.

Bone marrow biopsy Indications     •    In blood abnormalities in which it is impossible to confirm a diagnosis by means of peripheral blood examination.     •    In conditions like leucopenia, non-regenerative anaemia and thrombocytopenia.     •    As a confirmatory diagnosis of leukaemia and differentiating it from leukemoid reactions.

Samples for toxicological analysis are usually taken during post-mortem examination. In suspected cases of poisoning the following specimens should be sent for chemical analysis.

Certain casualties which are encountered in clinical practice are viz. acute peritonitis, anaphylactic shock, respiratory distress, cardiac arrest, ingestion of foreign bodies, hypomagnesemic tetany, diabetic ketoacidosis, toxic mastitis and poisoning. These patients required critical care, the critical patients are those patients whose conditions are capable of changing on a minute to minute or hourly basis or patients who could rapidly deteriorate in short notice. Proper treatment of emergency disease can help in the diagnosis of specific poisoning or disease on the basis of treatment response.

CLINICAL CASE RECORD Case No…………    Date……………. Clinician (Name)  Description of animal:    Species .....................    Breed .....................     Age  ...........................    Sex .........................     Weight .....................    Color ..................... Owner’s name & Address ...........................................................................