Overview of Veterinary Medicine

Medicine is the science of treating diseases dealing with diagnosis, treatment and prevention.

Veterinary Medicine includes combination of Anatomy, Physiology, Pathology, Parasitology, Microbiology and Pharmacology.

Branches of Veterinary medicine

There are two branches of Veterinary medicine

1. Clinical Veterinary Medicine - (internal medicine, curative medicine). Eg. Cardiologist, gastroenterologist etc
2. Preventive Veterinary Medicine - Maintain health and prevent and control animal diseases.

Classification of Disease

• Hereditary- transmitted to the offspring through mother or father.  Eg. haemophilia.
• Congenital - Disease acquired during intrauterine life Eg. Atresia anai, TB
• Acquired disease- contracted during the entire life span. Eg. cataract

According to specific cause

• Specific- produced by specific pathogen. Eg. RP, FMD
• Infectious- Living infecting organism Eg Virus, bacteria, protozoa

According to System Involved

• Localized- confined to a particular spot Eg. Abscess
• Generalized- all parts of the body Eg. Toxaemia, septicaemia

According to changes in the Organ

• Structural- change in structure Eg. Pericarditis, rickets, osteomalacia
• Functional- change in function without altering structure Eg. Arrhythmia

Stages of infectious disease

• Incubation period
• Premonitary symptoms
• Stages of development
• Subsidence
• Covalescence

According to clinical manifestation

• Acute- sudden onset, severe, short course, 3 to 14 days. Eg. RP, Anthrax, FMD
• Per acute- Duration is shorter than acute with very severe course. Illness lasts for few hr to 48hr. Eg. Peracurte mastitis
• Sub acute- onset and severity is less than the acute one. 2-4 wks
• Chronic disease- long run, fatal. Illness over 4 wks. TB

According to spread of disease

• Sporadic- spread in the herd
• Endemic- disease retained in the herd for a long time in a locality affecting large number of animals
• Enzootic- among animals in a definite area
• Epizootic disease- large population
• Panzootic disease-epidemic disease reaches some unusual size in another country

According to source of infection

• Exogenous- Animal gets infected from other animals, foodstuffs
• Endogenous- auto-infection activation of microorganism due to disturbance of internal medium Resp. Tract infection.

Diagnosis

Diagnosis is the art of recognition and determination of the nature of disease

Classification of Diagnosis

• Snap shot diagnosis - declared at very approach, erroneous
• Direct- observing lesions
• Tentative- based on subjective changes, laboratory tests
• Symptomatic- based on pathological changes
• Differential- comparing
• Exclusion
• Confirmatory – clinical, biochemical, pathological and immunological
• Herd Diagnosis- affected animal shows clear symptoms. Search the environment where the animals are kept in pasture , housing conditions, grazing etc., Post mortem, pathological findings, all supervision of experts from various disciplines. 

Other terminologies

• Typical symptom- typical of the disease
• Syndrome- associated to the disease
• Lesion- structural changes in an organ
• Prophylactic measures- prevent the spread of disease thru quarantine, vaccination, disposal, nutrition
• Prognosis- forecast disease. Favourable, doubtful, poor, grave
• Relapse- reoccurrence of the disease

Why Veterinary clinicians face problems while making a diagnosis

• Animals cannot express so we have to depend upon our own observations
• Diagnosis becomes erroneous when we have to depend upon attendants
• Sometimes animals do not cooperate
• Different species of animals have different structures and functions
• Variation in normal physiology (temp, pulse, respire) in different species of animal

References 

• Amalendu Chakrabarti, 2008. Text Book of Clinical Veterinary Medicine, Kalyani Publishers, New Delhi
• Jagdish Prasad and Neeraj, 2004, Principles and practices of Animal Health and Hygiene,  Kalyani Publishers, New Delhi

Content Contributors

• Saroj Rai, ICAR-National Dairy Research Institute, Eastern Regional Station, Kalyani, West Bengal Email : drsaroj.rai@gmail.com
• Rani Alex, ICAR-National Dairy Research Institute, Karnal, Haryana. 
• Ruma Jas, West Bengal University of Animal and Fishery Sciences, Belgachia, Kolkata, WB, India