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The X-ray film is the major element that record the image of part exposed with X-rays. Although the situation is changing with the introduction of new technologies in recent years. The film can be exposed by the direct action of X-rays, but more commonly the X-ray energy is converted into light by intensifying screens and this light is used to expose the film. The X-ray film is somewhat similar to photographic film in its basic composition. However unlike photographic film, the light (or radiation) sensitive emulsion is usually coated on both sides of the base of X- ray film so that it can be used with intensifying screens. Because of its importance to medicine, X-ray film is manufactured with consistent uniformity and quality, which facilitates standardization of exposure and processing.

After the patient has been radiographed, the exposed X-ray film is processed to produce the consistent quality radiographs. Film processing can be manually, or use an automatic film processor.  Manual film processing is a multi-stage process involving five basic steps in processing X-ray film: 
    i)    Developing 
    ii)    Rinsing 
    iii)    Fixing
    iv)    Washing
    v)    Drying. 

Artifacts are any unwanted radiographic densities in the form of blemishes arising from improper handling x-ray film, exposure, processing, housekeeping or setting up a technique for an examination. Artifacts will reduce the overall quality of the radiograph and in certain cases may nullify its diagnostic outcome. An idea about the possible errors is desirable in order to adopt corrective measures.

Orthopaedic Radiography
 
Radiography as an aid to diagnosis the orthopaedic cases has become an integral part of every modern hospital. This technique may also be helpful in detecting some previously unrecognized lesions in the area radiographed.

The radiologist must be aware of the radiological anatomy of part being examined, and of its normal variation with age, species and breed. The anatomical features which can be appreciated in a radiograph are:

Contrast radiography: The radiographic technique which employ the use of contrast media to identify a soft tissue structure or an organ and pathological findings which may be difficult or even impossible to visualize clearly in plain films due to lack of contrast with surrounding tissue is known as contrast radiography. This is a special radiographic techniques/procedures may be required to supplement or confirm the information obtained from plain or survey radiography. 
The substances used for this purpose is called contrast agents/medium/materials.

Radiology has been an important diagnostic modality in exotic animals and birds (includes rodents, reptiles and fish). The radiographic equipment needed for radiography of exotic animals and birds is basically the same to that used for domestic animals. A high-milliamperage (mA) X-ray machine, having 200- or 300 mA unit is recommended to allow the use of a short exposure time (1/40 seconds) or less are preferred. Maximum kilovoltage (kVp, 40-75) is less important for avian and exotic radiography than for domestic animal radiography. As with other species, at least two radiographic views at 900 angles to each other are recommended. However, restraining and knowledge of radiographic anatomy of different species of exotic animals and birds are the prerequisite for the modality. Restrain and immobilization:

Diagnostic imaging refers to technologies that doctors use to look inside the body of the patient for clues about any disease condition. A variety of machine and techniques can create pictures of the structures and activities inside the patient body. In India, some of these modalities like digital radiography and ultrasonography are being used at some of the veterinary colleges and reaseach institutes while at some places some of the veterinarians have access to the techniques like computed tomography (CT) and magnetic resoncace imaging (MRI) of the human hospitals. So this is the responsibility of the scientists and researchers engaged in the advancement of the diagnostic imaging and the manufacturing companies to make these facilities cot effective so that an animal of a common man can be benefited with these facilities.

Radiation therapy is the delivery of ionizing radiation to a specific body areas with the goal of obtaining maximum lesion control with minimal complication. Radiation therapy is based on the fact that ionizing radiation is lethal to the cells, particularly rapidly dividing ones. Normal cells in the irradiated area may be as sensitive to ionizing radiation as tumor cells. Therefore, the normal tissue response limits the amount of ionizing radiation that can be tolerated by the patient. Effective use of radiation therapy requires an understanding of the physics of the radiation used and normal cellular and tumor biology as it relates to radiation therapy as well as an appreciation of the clinical application of veterinary radiation therapy.

It has been well established that the risk of health problems rises as the amount of radiation exposure increases. All types of radiation produce changes in the living tissues. The resultant cellular injury causes physiological and pathological changes leading to “Radiation sickness”. The radiation effects may be somatic or genetic. Somatic effects are harmful to a person in his lifetime whereas genetic effects affect generations. Radiation may cause changes in complex molecular systems of living cells, primarily in following two ways :- 

Livestock production is an integral part of agriculture and plays a significant economic role in most developing countries. It contributes to poverty alleviation, food security and provides elements that are essential to the national economy. Livestock production accounts for 40% of the gross value of the agricultural production globally and this figure is likely to go up, as the demand of livestock products is increasing rapidly with the increase in income and urbanization (FAO, 2012). For poor farmers, animal ownership ensures varying degrees of sustainable development and economic stability. Livestock provide a stable cash reserve independent of inflation and are an important source of traction. Livestock are closely linked to the social and cultural lives of several million people. Quality and quantity of feed is essential for optimum animal productivity. Inadequacy of quality animal feed resources is most often the crucial factor for livestock production. The success of livestock is greatly dependent on continuous supply of good quality nutritious feed at competitive price. Poor nutrition of animals has been identified as the major constraints to animal production across the developing world (FAO, 2000). Feed is the major input cost in animal production system, accounting for 65-70% of the total rearing cost.

Silage is the material produced by controlled fermentation of forages or crop residues with high moisture content. The objective of silage making is to preserve the harvested forages by anaerobic fermentation in which soluble carbohydrates are converted into acids. Due to acid produced, pH of a well-ensiled product becomes so low that all life processes come to a halt and the material remain preserved so long as it remains in airtight storage. Soluble carbohydrate present in forage is converted to lactic acid which drops the pH to a level sufficient to inhibit any further biological activity in the ensiled forage mass (McDonald, 1991). Fresh forage crops, such as maize, grasses, legumes, wheat and Lucerne, can be preserved by ensiling. It is essential to have a good microbial fermentation process to produce high quality silage. Good silage is achieved by discouraging the activity of plant enzymes and undesirable micro-organisms and encouraging the dominance of lactic acid bacteria. A good fermentation process is not only dependent on the type and quality of the forage crop, but also on the harvesting and ensiling technique. Silage-making is a managemental tool that allows producers to match feed resources (forages, crop residues, agro-industrial byproducts, etc.) with feed demand for a dairy herd.

Ensiling is the term given for all physical and chemical changes that take place when forage with sufficient moisture content (60-65%) is stored in the absence of air for silage preservation. Silage fermentation is an exceptionally complex process involving biochemical interactions among the forage, microbial populations and the ensiling environment. Successful silage production depends upon the promotion of the fermentation brought by beneficial bacteria. The process is based on spontaneous lactic acid fermentation under anaerobic conditions. The lactic acid bacteria ferment the water-soluble carbohydrates in the crop to lactic acid, and to a lesser extent to acetic acid. Due to the production of these acids, the pH of the ensiled material decreases and spoilage micro-organisms are inhibited. The ideal characteristics of material for silage preservation are: DM content above 20% and an adequate level of fermentable substrate (8-10 percent of DM) in the form of water soluble carbohydrate. The ensiling material should also ideally have a physical form that allows easy compaction in the silo. Materials such as maize stover, sorghum stover and grass can be ensiled successfully, while crop residues such as rice and wheat straw, with low water soluble content, do not fulfill these requirements, and therefore pre-treatments, such as fine chopping or use of additives, or both, may be necessary.

A silo is an airtight to semi-airtight structure designed for the purpose of preservation and storage of high moisture feeds as silage.
 
Role of the silo in silage making

Silo has only three functions in the ensiling process:
    1.    To provide a solid surface to permit compaction of the mass to eliminate air;
    2.    To protect the ensiled materials from air and water during the storage period;
    3.    Where desired, to aid in the removal of silage by providing a base for unloading equipment.

Successful preservation of high-moisture forage and other crops depends upon the controlling the activities of microbes, particularly bacteria. Ensiling generally controls microbial activity by a combination of an anaerobic environment and a natural fermentation of sugars by lactic acid bacteria on the crop. The silage microflora plays a key role in the successful outcome of the conservation process. Therefore, it is important to understand both the microorganisms that are present on the crop at ensiling and how ensiling preserves the crop, inhibiting detrimental microorganisms. The crop at ensiling contains both aerobic and anaerobic microorganisms and a range of both bacteria and fungi that affect silage quality.

Silage fermentation is a complex process involving biochemical changes by microbial populations and the ensiling environment. The chemistry and microbiology of silage fermentation are linked, but the microorganisms are the dominant factor in the fermentation process, and they have the main influence on the quality of the end product. Many species of microorganisms are involved in the fermentation process, and their relative importance varies according to the prevailing conditions. As these conditions change during the fermentation process, the microorganism population changes accordingly. Lactic acid bacteria and clostridia are two main categories of microbes responsible for biochemical changes in silage.

Silage fermentation is a dynamic process that is affected by variety of factors. The primary goal of making silage is to maximize the preservation of original nutrients in the forage crop for feeding at a later date. Unfortunately, fermentation in the silo is a much uncontrolled process usually leading to less than optimal preservation of nutrients. In order to assist in the fermentation process, various silage additives have been used to improve the nutrient and energy recovery in silage, often with subsequent improvements in animal performance (Henderson, 1993; Bolsen et al., 1996; Muck and Kung, 1997; Kung and Muck, 1997; Muhlbach, 2000). Their main functions are to either increase nutritional value of silage or improve fermentation so that storage losses are reduced. The benefits obtained from silage additives depend upon their influence on the silage fermentation process. These benefits are usually measured by the reduction in fermentation losses and/or improvement in silage quality and feeding value.

Quality of silage is determined by nutrients content and intake potential of the silage. High quality silage is a stable feed, made from high quality pasture, which is preserved in the absence of oxygen by a high quality fermentation, to minimize any loss of feeding value. It is not possible to produce high quality silage from low quality pasture, no matter how good the fermentation is. The silage quality is generally used to indicate the success of fermentation and not to evaluate the feeding value of the silage. However, the fermentation quality and nutritional value of the silage are usually highly correlated because a poor fermentation can result in great loss of the digestible nutrients (Sutoh et al., 1970; Uchida and Sutoh, 1973). Therefore, both the quality of the ensiled pasture and the quality of the fermentation must be considered.

Silage fermentation is a dynamic process involving interactions among the forage, microbial populations and the ensiling environment. A good fermentation process is not only dependent on the type and quality of the forage crop, but also on the harvesting and ensiling technique. There are various factors that influence the fermentation process and ultimately the nutrient composition and quality of ensiled feed. These are as follows:

1. Plant Factors

Forage characteristics at the time of ensiling are the predominant factor which determines the final quality of silage. Factors such as type of forage to be ensiled, maturity, DM content and WSC content of that forage, all influence the ease of ensiling and ultimately the quality of silage that is produced.

It is recognized in developed countries that the production of silage of high quality cultivated forage can be a valuable component for the development of a high-performing and low-cost system of animal production, using a relatively low level of purchased concentrates. However, this appears inappropriate for smallholders in tropical countries, primarily due to lack or high cost, or both, of equipment for harvesting and conservation and production of cultivated forage being often limited due to lack of available land. Many agricultural, agro-industrial and fishery by-products have potential as animal feeds. Most farmers in developing countries rely for their food security on the cultivation of cereals, root crops and high-value crops such as fruits and vegetables, which understandably take priority in the allocation of land. Fruit, vegetables and root crops are increasingly integrated in the farming system and play a key role as staples in the human diet in most developing countries.

Objective of the conservation of forage is to preserve as much as of the crop nutrient as possible. However, during ensilage loss of nutrients occurs. There are five sources of loss. Theses are:
 
    (a)    Field losses 
    (b)    Oxidation or respiration losses 
     (c)    Fermentation losses
    (d)    Effluent losses 
    (f)    Aerobic deterioration

Feeding silage is also an important part of the process. Silage can be fed to all kinds of animals. Silage is suitable for feeding 6-7 weeks after ensiling. Purposes of silage feeding are drought feeding, production increases, an aid to pasture or crop management, utilization of excess growth, balancing nutrients in the diet, and the storage of wet feed products. Silage is most likely to be profitable when used to increase productivity or balance nutrient content of the diet.
 
Feeding value of silage is defined as the product of the nutritive value and potential voluntary intake of the forage (Wheeler and Corbett, 1989).

Forage preservation as silage is a key component of high input (zero-grazing) systems (Mannetje, 1999). It has allowed producers to intensify the productivity of the land and the productivity of the livestock. Large quantities of forage can be conserved in a short time, forage conservation is less weather dependent and thirdly, silage is well suited to mechanization. However, a major disadvantage associated with silage making is that the feeding value of the resultant forage is reduced relative to that of the original crop. Ensiling offers many advantages over haymaking.

Feeding of green and succulent fodder is of utmost importance to farm animals. Grazing fresh forage year round at the optimal stage of maturity would supply the highest quality and most palatable form of feed in any livestock operation. In most part of the world, green fodder is limited to a particular season only. Because of fluctuations in seasonal growth and plant maturity, excessive biomass in the spring, it is necessary to harvest and store forages to maximize both quality and productivity. One of the important form of conservation practiced on a wide scale is hay making. Hay making is an art in which the fodder is kept for future use in lean period. Since it contains large quantity of moisture it is to be dried properly to increase its keeping quality without reducing its nutritive value. The objective of hay making is to achieve a rapid moisture loss after cutting so that the forage can be romoved from the field with minimum losses from weathering and microbial degradation (Bareebam, 1992).

Hay quality really means feed value. The ultimate test of hay quality is animal performance. Quality can be considered satisfactory when animals consuming the hay give the desired performance.
 
Characteristics of Good Quality Hay

    1.    Hay should be nutritious therefore prepared form plants cut at an appropriate stage of maturity when it has the maximum nutrients.
 
    2.    Good hay should be leafy. The leaves are generally richer in proteins, minerals and vitamins then other parts of the plant.

    3.    Hay should be green in colour. The green colour indicates the amount of carotene which is precursor of vitamin A. The green colour should be preserved by minimizing the bleaching, leaching arid fermentation losses.

Storage of hay at higher moisture contents may lead to some heating due to the activity of aerobic micro-organisms and possibly some plant respiration. The warm, moist conditions in hay will provide the ideal environment for growth of spoilage bacteria, e.g. Bacilli and yeasts, moulds and fungi. These organisms utilize the energy and protein of the hay and can lead to a substantial increase in their respective populations. Their action leads to the following reaction:- 

Hay (plant sugars) + oxygen ® Carbon dioxide + water + heat
 
The resultant heating causes a reaction between the carbohydrates and proteins rendering both less digestible as temperatures continue to increase. The best opportunity to reduce hay-harvesting losses is by shortening curing time. A combination of mechanical conditioning, chemical conditioning and high-moisture baling help accomplish this goal (Collins, 1988; Mahanna, 1994).

Haylage or baleage or round bale silage, is a somewhat newer method of preserving forage. Haylage is simply forage that is baled at higher moisture content than dry hay and then stored in a sealed plastic wrap. Because of the high moisture level and air-tight environment, the forage ferments and is preserved by acid production during fermentation. The higher pH values associated with baleage are related to a slower fermentation process. During the respiration stage of the ensiling process the oxygen that is trapped in storage is rapidly consumed by aerobic bacteria. Anaerobic bacteria, which survive in the absence of oxygen, begin to grow and multiply in the fermentation stage and convert the plant sugars into organic acids- mainly lactic acid and acetic acid. With production of acids, the pH of the silage is reduced from an original level of 7.0 to a final ideal pH of 4–5. Typical large bale haylage has a pH of 4.5–5.5. Fermentation ceases when bacteria growth is stopped by the accumulation of acids. The haylage will then remain at a stable pH with no bacterial growth and can be preserved for a long time, providing there is no exposure to air. Harvesting forages with a long fiber usually results in a slow release of the plant nutrients necessary for the growth of acid producing bacteria. This generally results in less fermentation in the baleage than in chopped silage.

Analyzing feeds for nutrient content is essential for proper balancing of livestock rations. This is especially essential for those feeds that have undergone the fermentation process. Silage samples should be analysed for dry matter, protein fractions (degradable and undegradable protein, soluble protein, and heat damaged protein), ADF, NDF, mineral content and energy. In addition to these components, lactic, acetic, and butyric and propionic acids, pH, ammonia nitrogen, ethanol, and yeast and mold counts are also quantified.

Surgery : The branch of medical science which deals with the treatment of injuries, deformities or disease condition by manipulation or operations with the hand. The term surgery is derived from a Greek word – Chirurgia. 
Cheir – Hand 
Ergon – Work 
Veterinary surgery : Veterinary surgery is the surgery which is practiced on animals. 

Surgical Plan
i. Pre-operative Course of Action 
    a.    Client communication.
    b.    Clinical laboratory evaluation, radiograph, treatment for fluid or blood volume deficits. 

ii. Intra-operative Plan of Action 
    a.    Surgical approach 
    b.    Material and equipment needed 
    c.    Technical and support personnel

Sterilization is a process of killing all microorganisms, including bacteria, fungi and their spores, and viruses from animate or inanimate surfaces with the use of either physical or chemical agents. Joseph Lister first gave antiseptic principle in 1867.

Sutures or surgical threads : means a material used to hold the edges of tissue in close approximation. 

Objectives
    1.    To facilitate healing. 
    2.    Haemostatic.
    3.    To retain drainage tube and implants. 
    4.    To reduce the size of natural opening.

There is a delicate balance among electrolyte concentrations, body water and acid base status to maintain body homeostasis. Disturbances in homeostasis results in life threatening abnormalities. The aim of fluid therapy is to replace losses and maintain fluid and electrolyte balance in the body.

Shock is a life threatening condition which is usually manifested by serious pathophysiological abnormalities. In most cases it is due to poor tissue perfusion with impaired cellular metabolism.

       It is a clinical state resulting from an inadequate supply of oxygen to the tissues or an ability of the tissues to properly use oxygen.

       Shock can also be defined as imbalance between oxygen supply and oxygen consumption. In other words, the delivary of oxygen does not meet the needs of the tissues.

       Shock is a state in which the vital functions of the body are depressed because of acute reduction in cardiac output and effective circulating blood volume.

Dissolution in the continuity of bone/cartilage with or without displacement of fractured fragments is known as fracture.

Classification
1. On the Basis of Communication of Fractured Site to the Environment
    a.    Simple fracture : The fracture site does not communicate with the environment. 
    b.    Compound fracture : The fracture site communicates with the environment.  This type of fractures is more prone to infection. 
    c.    Complicated fracture : A closed fracture in which there is considerable injury to important neighboring vessels or nerves or accompanied by the opening of a joint or vascular cavity.

A wound is defined as a breach or disruption in the normal continuity of tissue in any body part. The wounds are mainly caused by physical, chemical or biological insult.

Burn : Tissue changes due to excessive absorption of heat is known as burns.
Scald : A scald is a burn caused by moist heat and is usually partial thickness.

Etiology
       Dry heat
       Actinic rays (sunburn)
       Irradiation
       Moist heat
       Electricity
       Friction
       Dry heat causes desiccation and charring.

A hernia is the protrusion of an organ through a defect in the wall of the abdominal cavity in which it lies.

Classification
1. On the Basis of Anatomical Site
    Abdominal (umbilical and ventral)
    Diaphragmatic

It is defined as the reaction of living tissue to injury which begins following a sub-lethal injury to tissues and ends with complete healing. The purpose of inflammation is to destroy and remove the irritant and to repair the damaged tissue. 

Causes
    1.    Pathogenic organisms: Bacteria, virus, fungi, protozan and parasites.
    2.    Chemical poisons: Acid and alkalies. 
    3.    Mechanical or thermal injuries. 
    4.    Immune reaction: Antigen antibody reaction.

Sprain : It is defined as a joint injury in which fibers of supporting ligaments of the joint are ruptured by direct or indirect trauma. Depending upon the degree of ligament rupture, sprain can be classified as follows: 

Inflammation of the joint is known as arthritis.
Coxitis : Inflammation of hip joint.
Gonitis : Inflammation of stifle joint.
Omarthritis : Inflammation of shoulder joint.
Carpitis : Inflammation of carpal joint.

Luxation/Dislocation : It refers to the displacement of opposing articular surfaces of bone. The direction of displacement is described with reference to the distal bone in relation to the proximal bone.

Subluxation : It refers to partial or incomplete dislocation.

Classification
    1.    Acute : Recent occurrence of luxation.
    2.    Chronic : Luxation existing for a long time.
    3.    Recurrent : Reluxation after correction.
    4.    Simple : No open wound is communicating with the joint.
    5.    Compound : Open wound is communicating with the joint.
    6.    Pathological : Dislocation due to any pathological lesion.

Arterial diseases are important because of their serious effect on vital organs like brain, heart and kidney. Thrombosis is the most common complication of arterial diseases but hemorrhage and aneurysm formation may occur.

  Term anesthesia by Dr Oliver Wendell Holmes (1886).
  Anasthesis (Greece Word) – absence of sensation.

History of Animal Anesthesia
  Paracelsus (1540) produced ether and reported it to have a soporific effect on fowl. 
  Sir Humphrey Davy (1800) suggested that N₂O might have anesthetic property. 
  Chloroform was discovered by Liebig in 1831.
  Dr. Horace Wells (1844) discovered the general anesthetic properties of nitrous oxide. 

Preanesthetic agents are so named because they are usually given to prepare the patient for administration of an anesthetic agent for one or more of the following reasons:

    1.    To reduce the amount of general anesthetic needed and increase the margin of safety.
    2.    To calm the patient so that anesthesia can be administrated without fright or struggling. 
    3.    To reduce secretions of salivary glands (antisialogogue) and mucous glands of the respiratory tract, thus maintaining a free airway. 
    4.    To reduce gastric and intestinal motility and prevent vomiting while the patient is under anesthesia. 
    5.    To block the vagal reflex, thus prevent cardiac slowing or arrest (bradycardia).

General anesthesia : reversible complete loss of consciousness along with analgesia. 
  Unconsciousness occurs due to depressant action or functional disruption by stimulation in brain by anesthetic agents.
  Analgesia is probably due to blockade of synaptic transmission in the dorsal horn of the spinal cord.

Injectable Anesthesia

Injectable anesthetics are the agents which are administered to the patient parentrally. They include drugs which are given intravenously to rapidly induce anesthesia in a patient. Single or combinations of drugs usually administered intramuscularly to patients which are difficult to handle. Injectable agents generally require less equipment and are easier to administer than inhalation anesthetics, but it must be remembered that once they are given to a patient they cannot be removed.

Advantages
    1.    These agents are primarily exhaled through the lungs and recovery is not dependent upon redistribution within the body and detoxification mechanisms. This is helpful in poor risk patient.
 
    2.    Anesthesiologist has good control over the anesthesia.
 
    3.    Early recovery of the patient.

    4.    Closed system available for thoracic surgery.

A sound understanding of general anesthetic emergencies and surgical techniques is vital for all practicing veterinarians. In most of the veterinary practices, after induction of anesthesia, no one is assigned the task of anesthetist to monitor anesthesia and occurrence of complications during surgery which may lead to the development of anesthetic emergencies. Onset of general anesthesia disturbs the physiological equilibrium of patient and increase the threshold of harmful events. The harmful events of anesthesia includes:

Endotracheal intubation is the placement of a tube in the trachea to provide a patent airway.

It is a valuable technique that enables to attach an animal to a breathing circuit or, just as importantly, to secure an airway during an emergency such as respiratory or cardiac arrest.

It is important that time be taken to learn the anatomy of the laryngeal area and the skill of intubation so that intubation may be performed quickly and with little chance of misplacement.

Historical Aspect
    Curare was the first known muscle relaxant which was used by South American Indians to immobilize wild animals. Hence the term curariform has been applied to the action of this group of drugs. 
    In year 1958, a plant alkaloid alcuronium was introduced but there were difficulties in reversing the action of this drug.
    Succinylcholine was first used in 1906. However, its paralyzing property was discovered in year 1949.
    Pancuronium was introduced in 1964.