Concepts in General Veterinary Medicine.pptx

This presentation introduces you to the concept of Veterinary Medicine, health, diseases, signs, diagnosis and prognosis.

1. General Veterinary Medicine Presented by: Dr . Desh Deepak Assistant Professor, Veterinary Medicine, SVPUAT

2. Veterinary Science Veterinary Science deals with the anatomy, physiology and pathology of animals other than man. It includes the diagnosis, prophylaxis, and treatment of their diseases and infirmities, their relationship to man with regards to intercommunicable diseases and to the use of their flesh and other products and their scientific breeding, feeding and handling. (Encyclopedia Britanica).

3. Medicine & Veterinary Medicine (VMD) Medicine or healing art is science of treating diseases. Veterinary Medicine is branch of medical science that deals with diagnosis, prevention, treatment and general studies of animal diseases especially of domestic ones. Or Veterinary medicine is branch of medical science that deals with application of medical diagnostic and therapeutic principles for companion, domestic, production, exotic and whole wildlife. Veterinary medicine may be divided in two branches namely clinical medicine and preventive medicine.

4. To study the phenomenon of disease without book is to sail an unchartered sea, while to study books without patients is not to go to sea at all

5. Branch of Medicine Clinical or curative or internal medicine is branch of veterinary medicine which covers the art of making a correct diagnosis and extending remedial and curative measures against diseases of animals. Preventive medicine is branch of veterinary medicine which deals with the diseases of infectious and contagious nature, its occurrence among animal population and its prevention and control by suitable and appropriate measures.

6. Veterinarian Synonym : Veterinary practitioner or Animal Doctor or Vet Veterinarian is a professional who is legally qualified to treat diseased or injured animals. There are three specialization in veterinary science namely veterinary medicine (veterinary physician), veterinary surgery (veterinary surgeon) and veterinary gynecology (veterinary gynecologist) but every veterinarian needs to serve the duty of each of them.

7. Health World Health Organization defines “Health as state of complete physical mental and spiritual wellbeing of an individual”. Blood and Studdert in veterinary dictionary define “health as state of physical and psychological well-being and of productivity including reproduction”.

8. Health C.S.G Grunsell in Black’s veterinary dictionary define “health as state of maximum economic production” As a conclusion to all these definitions, animal health can be credited as a state of normal structure, function and relation of body tissues to environment (homeostasis), tendency to show normal instincts and behaviour, ability to produce healthy off-spring and animal products at its maximum genetic potential. Therefore for veterinary clinician achieving structural, functional and behavioral normality is not a sole task but reestablishment of normal animal production is also essential and at times animal welfare and animal production donot go similar way.

9. Disease Concept of disease can be understand as complex negative health phenomenon caused by some specific single or multiple etiologies, associated with some structural or functional dysfunction and manifested as recognizable set of symptoms and signs. Baker and Geer define disease as condition not at ease (“dis” meaning reversal and “ease” for easiness ). Blood book credited as bible of farm animal veterinary medicine and titled as “A text book of disease of cattle, sheep, pig, goats and horses”, states disease as any abnormality associated with any structure and function of animal . Gillespie and Timoney define disease as alteration is state of body or some of its organ interrupting or disrupting the proper function of bodily function .

10. Classification of disease Basis: Intensity and spread of diseases Endemic diseases are the diseases with constant presence of a disease in a population or usual frequency of occurrence of a disease in population e.g. FMD in India. Epidemic diseases is defined as sudden and usually unpredictable increase in number of cases of an infectious disease in a population e.g. Coccidiosis in poultry, Influenza except caused by H 5 N 1 and H 1 N 1. Pandemic diseases are widespread epidemic that usually affects a large proportion of population. It involves many countries e.g. COVID-19, H 5 N 1 and H 1 N 1 Influenza. Sporadic diseases are outbreak that occurs irregularly and haphazardly without any pattern e.g. Anthrax in South India.

11. Classification of Disease Basis: Mode of Genesis Hereditary disease are diseases transmitted to offspring from one of the parent. e.g haemophilia, Epilepsy. Congenital disease are diseases originating during intrauterine life and are manifested at birth e.g. Inutero hypovitaminosis A, atresia ani. Acquired disease are the diseases that are acquired during life time of individual after birth e.g. haemorrhagic septicemia.

12. Classification of disease Basis: Mode of infection Primary or principal disease are the disease whose origin is not influenced by another disease e.g. Rabies, canine distemper. Secondary disease are the diseases which supervenes out of already prevailing primary disease e.g. Secondary bacterial infections. Intercurrent disease are the diseases occurring as sequelae to primary disease e.g. Purpura hemorrhagica as sequel to strangles.

13. Classification of Disease Basis: Gradient of infection Inapparent infection refers to infection of any susceptible host without manifestation of any clinical sign. Subclinical infection refers to infectious or non-infectious diseases occurring without manifesting overt clinical signs. Clinical infection refers to infections that occurs with manifestation of clinical signs. The infection may be mild, moderate or severe in nature.

14. Classification of Disease Basis: System involved Localized disease are the diseases in which clinical or pathological change occurring is confined to a particular organ or spot e.g. Gastritis, stomatitis. Generalized disease are the diseases in which pathological process affects most organs or part of body e.g. Septicemia, toxemia.

15. Classification of Disease Basis: Course and onset of clinical manifestations Per-acute disease are the disease with very short and severe course. Disease lasts for few hours to maximum of two days e.g. haemorrhagic septicemia. Acute disease are characterised by sudden onset, course up to two weeks and severe clinical manifestations e.g. Foot and Mouth disease. Sub-acute disease are the diseases with slightly long course and less severity as compared to acute diseases. These diseases usually has course of 2 to 4weeks e.g. sub-acute mastitis. Chronic disease are the disease with course of more than 4 weeks to several years. Clinical manifestations are not acutely severe but terminates fatally e.g. Tuberculosis. Carrier is an infected animal that sheds an infectious agents without showing clinical sign. If shedding occurs during incubation period then it is referred as incubatory carrier e.g. rabies. If shedding occurs during recovery phase of disease then called as convalescent carrier e.g. FMD shedding up to 2 years after infection. Carrier state of duration less than 3 months is considered as acute while carrier state of more than 3 months is considered as chronic.

16. Classification of Disease Basis: Origin of disease Indigenous disease are the disease that is native for that region. e.g. tuberculosis in India. Emerging diseases are the zoonotic diseases caused either by apparently new agent or by previously known microorganism appearing in new places or species in which the disease was previously known e.g. H5N1 influenza. Reemerging diseases are the infectious agent that has been known for some time had fallen to such low level that they were no longer considered public health problem and are now showing upward trend. e.g. Plague

17. Determinants of disease Primary determinants are the necessary factors for inducing a disease. Example include etiology and factor like trauma for setting of mastitis . Etiology refers to actual precipitating factors for eliciting the disease process. Based on etiology, diseases can be divided in to specific, non-specific, iatrogenic, nosocomial and idiopathic disease 1. Specific disease is disease caused by a specific pathogen or factor. It can be of two types Infectious disease are the diseases caused by live infectious organism like bacterial, fungal, viral and protozoal diseases. Contagious disease are the infectious diseases which spread by intimate contacts like F.M.D and Rinderpest. All contagious diseases are infectious disease but all infectious disease may or may not be contagious.

18. Determinants of disease 2. Non-specific disease are the diseases with multiple causes like diarrhea, pneumonia etc. 3. Iatrogenic diseases refers to disease caused by therapeutic or diagnostic procedure performed on an animal. It can be caused by any drug or any surgical procedure but donot includes non-medical interventions and unauthorized prescriptions. 4. Nosocomial diseases or health care/hospital acquired/associated infections (HCAI or HAI) infections are the diseases or infections that are acquired from environment of hospital or health care facilities during medical care. 5. Idiopathic diseases refers to disease with unknown, unidentifiable or poorly understood origin, cause and mechanism. These disease are considered as separate entity during differential diagnosis from disease with similar manifestations and course.

19. Secondary determinants Secondary determinants are facilitating factors which are not necessary for induction of a disease process but their presence supports onset or aggravates manifestation of a disease. These factors include predisposing, precipitant, enabling and reinforcing factors. Predisposing factors refers to factors associated with the host which increased the susceptibility of that particular host to an infection or disease. Example include predisposition of pups for parvoviral gastroenteritis. Precipitating factors are the determinants or events that induces definite onset of any disease for example stress leads to precipitation of hemorrhagic septicemia Enabling factors are the factors associated with a disease process that facilitate manifestations of disease. Example include housing and nutritional status. Reinforcing factors are the factors that are known to exaggerate the pathogenesis of disease like immunosuppressed patients suffers sever clinical manifestations of demodex.

20. Manifestations of disease Symptom is adverse feelings by the animals owing to abnormalities in bodily or mental condition. Symptoms can be classified in to various types . Sign is the outward manifestation of a disease observed through objective evidence. Syndrome refers to constellation of sign and symptoms and collection of diseases which are not correlated with each other and often associated with a particular disease or disorder e.g. uraemic syndrome. Lesion is the structural changes observed in organ or part of organ.

21. Manifestations of disease Symptom is adverse feelings by the animals owing to abnormalities in bodily or mental condition. Symptoms can be classified in to various types. Subjective symptoms refers to feeling expressed by the patient. Objective symptoms refers to symptoms observed by clinician through various methods of examination. Typical or diagnostic symptoms or pathognomic symptoms refers to characteristic symptom which are always present in a specific disease and their presence directly establish occurrence of a disease. E.g. Septicemia along with crepitation of muscles is typical for black quarter. Atypical symptoms include symptoms which are irregular and do not bear any conformity of typical symptoms. E.g. Nervous manifestation in coccidiosis in calf .

22. Introduction Direct symptoms or idiopathic symptoms are symptoms with spontaneous origin and direct result of a disease process. E.g. vomition in gastritis. Indirect or sympathetic symptoms are symptoms which occurs as a result of affection in any other organ like uremia induced emesis or bloat induced dyspnea. Chronic symptoms are system which are observed for a long time or period. E.g. Diabetes, asthma etc. Premonitory symptoms or precursory symptoms are the symptoms which aids in forecasting about the health status of animal. E.g. anorexia, absent rumination etc. Periodic or remittent symptoms are the symptoms which entirely disappear or resolves after a short or long interval. E.g. biphasic fever in surra and canine distemper. Relapsing symptoms are the symptom which occurs, resolves and reoccur again. E.g. Hay fever.

23. Types of sign Sign is the outward manifestation of a disease observed through objective evidence. Classification of Sign Anamnestic signs are the signs which provides clue about disease history of patient. Ex. Presence of scar can be indicative of any past surgery or dermatitis in animal. Prognostic signs refers to signs which aids in determining the probable outcome of a disease. E.g. Start of rumination and appetite after initiation of therapy is indicative of favourable response to therapy. Diagnostic signs are the signs which aids in making a diagnosis. E.g. Abduction of elbow and avoidance of sitting and neutrophillia with left shift aids in diagnosing TRP. Pathognomic signs refer to sign characteristic for a disease and directly confirm the presence of disease.

24. Course of disease Latent period is period from infection to the occurrence of first manifestation. Prodromal period is period from first sign of disease to its complete manifestation. Period of manifestation is period of development of marked clinical manifestation. Recovery or cure is end of disease with restoration of normal function and complete recovery. It can occur by two methods Cure by lysis is gradual diminishing of marked manifestations and fever with slow return to health. E.g. Infectious canine hepatitis. Cure by crisis is rapid loss of manifestations and fever with rapid return of health. E.g. acute bronchopneumonia.

25. Course of disease Relapse means recurrence of the disease after clinical cure during the period of convalescence. E.g. recurrent endocarditis. Complication is a disease which occurs due to increased susceptibility of infection due to other disease. Convalescence is a state through which a patient passes after a prolonged illness till it regains normal health and optimum power of production. Sequelae refers the affection which may arise after the apparent recovery of a primary disease. E.g. Chorea as a sequelae of canine distemper. Zoonosis are those disease and infections which are naturally transmitted between vertebrates and man. E.g. rabies

26. Diagnosis Diagnosis is art of recognition and determination of nature of disease A complete diagnosis should includes The Specific cause. The abnormality of structure or function produced by causative agent. The clinical manifestation of that abnormality produced by causative agent. Example: Equine Rhodococcus equi pneumonia and lung abscess.

27. Classification of Diagnosis Snapshot diagnosis is diagnosis at a glance. Direct diagnosis is diagnosis made by observing some structural and pathognomic signs. Differential diagnosis is art of diagnosis by comparing and contrasting similar diseases. Tentative diagnosis refers to diagnosis made on the basis of subjective changes investigated through clinical examination. Exclusion Form of diagnosis: diagnosis made by ruling out all other similar diseases. Symptomatic diagnosis : diagnosis made on the basis of principal pathogical changes. Confirmatory diagnosis : Diagnosis on the basis of clinical and clinic-pathological examination. Laboratory diagnosis : Diagnosis made through examination of various pathological materials. Herd diagnosis : Diagnosis of a disease affecting whole herd.

28. Methods of Diagnosis The Syndrome or pattern recognition method refers to diagnosis based on the comparison of subject case and previous case in the clinician’s memory and the one is recognized as replica of other. Hypothetico-Deductive reasoning is a method of generating all possible diagnosis from clues derived from clued derived from history then one by one excluding the disease The Arborisation or Algorithm method is extension of hypothetico-deductive reasoning according to a preplanned programe .

29. Methods of Diagnosis 4. The Key Abnormality Method is a time consuming method and consist of five steps. General physical examination determines abnormality of function present. Special examination of suspected system or organ determines system or organ involved. Special examination of identified system determines location of lesion in an organ. Special examination of lesion determines type of lesion. Special examination of lesion determines specific cause of lesion. 5. The Database method is also termed as weed oriented or problem oriented method refers to method with complete clinical examination of patient to create a comprehensive clinical database which is than matched or compared with diagnostic database already installed in the system to make a diagnosis. This method is followed by some teaching veterinary hospitals with the help of problem oriented veterinary medical record system which has four components viz database, problem list, initial plans and progress notes.

30. Prognosis refers to prediction of the course, duration and outcome of a disease based on the pathogenesis of the disease and the presence of risk factors for the disease. It is established after the diagnosis is made and before the treatment plan is established. Types of Prognosis Favourable prognosis is assigned for cases which are going to heal or cure without any complication. Good prognosis is assigned for cases with possible positive outcome or are easily manageable but has potential of some complication. Fair prognosis is assigned for cases which are either manageable or have favourable outcome but serious complications are also possible and recovery may be prolonged. Gaurded prognosis is assigned for cases with unknown or uncertain outcome. Poor prognosis is assigned for cases with underlying severe complications, with all the chances of unfavorable outcome and if somehow recovery possible it is expected to be prolonged. Grave prognosis is assigned for patients suffering from a disease process in which death is imminent. Prognosis

31. Therapy/Medical Treatment Therapy is the attempted remediation of health problem usually following a diagnosis. The word therapy is derived from Greek word “therapeutike”, which means medical practice. Therapy is a broad term which encompasses all available scientific modalities like drugs, surgery, diet, exircise, radiation etc. for the treatment of diseases.

32. Types of therapy Empirical therapy refers to use of drug on the basis of past clinical experiences of practitioner or for treatment which is initiated before diagnosis is established for example initiation of antibiotic therapy in a case before ABST. Specific or rational therapy refers to therapy which is prescribed on the basis of established scientific knowledge of pathogenesis of disease process and pharmacology of drug or recommended scientific protocols. Example includes administration of doxycycline for Ehrlichiosis and buparvaquone for theileriosis. Treatment of choice or Drug of choice refers to medicine, drug or surgical procedure which is best and scientifically established for a particular disease or affection . Replacement or substitutive therapy refers to therapy based on principle of exogenous administration of any deficient endogenous biological substance which is required for normal physiological function and homeostasis. Example includes administration of l-thyroxin in the treatment of hypothyroidism.

33. 5. Symptomatic therapy refers to treatment which aims to ease and manage the clinical manifestation without confirmed diagnosis. Example includes administration of diazepam to a convulsive animal or administration of antiemetic to vomiting animal. This type of therapy is not advisable since it gives a false impression of improvement in condition by easing the manifestation but in few cases it can be lifesaving too. 6. Supportive therapy refers to use of drugs to maintain physiological, structural and functional integrity of living tissue for a duration till animals become capable to recuperate or more specific treatment can be survived by the animal or there is no further requirement of treatment. Fluid and electrolyte therapy, administration of tonics (vitamin and mineral supplements) and antioxidants are part of supportive therapy commonly employed in day to day practice. 7. Palliative therapy refers to therapy with the aim of controlling the severity and suffering of disease to improve the quality of life. Example use of pain killers and sedatives in last stages of cancer. 8. General therapy or accessory therapy refers to treatment modalities which donot use drugs. It includes hydrotherapy (water), dietary therapy (food), heliotherapy (sunlight), mechanotherapy (exircise) and physical therapy (heat or light).

34. Thank you