Glossary

Virulence encoding genes of Prescottella equi. choE encodes for cholesterol oxidase and vapA encodes for VAPA protein which prevents phagolysomal maturation.

This is hosts where a pathogen can persist in the absence of other hosts i.e. the pathogen will continue to be shed and transmitted to other hosts of the same species.

An accumulation of pus within a fibrous capsule, usually surrounded by a band of inflammatory cells.

When a particular microorganism obtains the ability to resist the activity of a particular antimicrobial to which it was previously susceptible.

Adhesins are cell-surface components or appendages of bacteria that facilitate adhesion or adherence to other cells or to surfaces, usually in the host they are infecting or living in

Microorganisms that prefer to grow in the presence of oxygen. Most will not grow if deprived of oxygen.

The cause of a disease or condition. In the case of infectious disease, it is an infectious agent.

Firm attachment of bacterial structures to host tissue surfaces

Are medicines that either kill or inhibit bacteria

Antibodies are manufactured that specifically bind to the surface of their homologous antigen on the surface of infectious agents. The binding is observed as agglutination or a colour change depending on the test type used.

The mechanisms microorganisms use to resist the action of antimicrobials.

These are in vitro tests done on purified bacterial and fungal cultures that detect resistance to antibacterials and antifungals.

Atopy is the genetic tendency to develop allergic diseases such as allergic rhinitis, asthma and atopic dermatitis (eczema).

A bacterial colony which is produced on solid surfaces such as bacterial growth agar is produced from one mother cell. Millions of clones exist in a colony.

These are viruses that only infect bacteria. Virulent phages are those that destroy bacteria and can be used instead or together with antibiotics

Biofilms are communities of bacteria, either as a single species or several species that adhere to surfaces and produce a profuse, protective extracellular polymer substrate/matrix (EPS).

Biological hazards are organic substances that present a threat to the health of people and other living organisms

The application of knowledge, techniques and equipment to prevent personal, laboratory and environmental exposure to potentially infectious agents or biohazards.

Procedures or measures designed to protect a population against harmful biological or biochemical substances.

Biosafety level 3 (PC3). Microbes that can cause serious or deadly diseases via the inhalation route.

A long-acting 3rd generation cephalosporin with predominantly a gram-positive spectrum. Registered for skin and urinary tract infections in dogs and cats

Cellulitis is an acute inflammatory condition of the dermis and subcutaneous tissue. It is usually caused by bacteria.

Marine mammals = whales, dolphins and porpoises

These are diseases that last for a long time that become progressively worse. An example of a chronic infectious disease is Ovine Johne's disease caused by Mycobacterium avium subsp. paratuberculosis

Abdominal pain. Evidenced by discomfort, straining to urinate stance, lying down a lot, teeth grinding, kicking at abdomen and rolling

The establishment of micro-organisms at the portal of entry into the host. This is usually on surfaces such as all mucosae and the skin.

Microbes that are resident on the surface of mucosae and skin and often pose a barrier to infection. However, opportunistic pathogens can also be part of this population.

These are infectious agents that are spread between individuals. Communicable diseases that are easily transmitted are sometimes known as contagious disease.

This is when organisms exchange genetic material via direct contact with each other. Bacteria use the pilus as a bridge.

Resistance to other drugs within an antibiotic class or to unrelated drugs

Cryptobiosis is a state of extreme inactivity of an organism in response to adverse conditions i.e. desiccation, freezing, high osmotic pressures. During this time the organism does not reproduce or show any signs of metabolic activity. The tick layered endospore is a cryptobiotic state. D

Hosts from which infectious agents are not transmitted to other susceptible hosts.

Loose watery stool

the process of differentiating between two or more conditions which share similar signs.

DIC is a life-threatening condition that occurs when there are countless small blood clots throughout the body leading to clotting factor depletion. Without enough clotting factors uncontrollable bleeding occurs both internally and externally.

This is a vaccine where the measurable antibodies against it are different to a natural infection. This means that the vaccine can be used in animals for export where evidence of serological freedom of a specific disease-causing agent is required.

DNA topoisomerases are enzymes that catalyze changes in the topological state of DNA, interconverting relaxed and supercoiled forms, linked and unlinked species, and knotted and unknotted

Temporary surface attachment by bacteria using electrostatic or hydrostatic forces

The withdrawal period is that time after administration of antibiotic has ceased when the drug concentration in the food product (meat, milk, eggs) is below the maximum allowable residue limit

Destruction or disruption (imbalance) of the normal microflora on or in the body. Example: It occurs when there is broad-spectrum antibiotic therapy

Severe diarrhoea of predominantly the large intestine where there is blood and mucus in the stool.

Inability to swallow food or drink

Treatments that are based on observation and experience, rather than scientific evidence. Usually applied in life-threatening infections when immediate treatment is necessary.

End arteries or terminal arteries are those with no collateral circulation and supply oxygenated blood to a portion of tissue. They are found in the brain, liver, kideys and intestines.

Having an internal cause or origin.

A tough intracellular structure produced by some members of the Bacillota.

inflammation of the epidermis

Exospores are produced by separating the spore from the mother cell by a septum. Exospores are produced by some Actinomycetota.

Bacterial exotoxins in thebloodstream

Extended-spectrum beta-lactamases (ESBLs) are enzymes that confer resistance to most beta-lactam antibiotics, including penicillins, cephalosporins, and the monobactam aztreonam. Infections with ESBL-producing organisms have been associated with poor outcomes

Bacteria that can grow both in the presence of oxygen (aerobic) and when oxygen is not present (anaerobic).

inflammation of the fascia

Inflammation of the hair follicles

abscesses within the hair follicles

It acts as a bacterial protein synthesis inhibitor

Necrosis of tissues associated with lack of blood flow. The tissues change colour to plum-red or deep purple.

A tissue mass that is associated with chronic inflammation. This tissue is rich in macrophages and will contain other white blood cells like neutrophils. Infectious agents are the most common cause of granulomas.

Haematology is the branch of medicine concerned with the study of the cause, prognosis, treatment, and prevention of diseases related to blood. For most animals this will involve the measurement of different components of the blood and microscopic examination of blood films.

Blood in the urine

Increased concentration of solids and cells in blood caused by loss of fluid.

Presence of haemoglobin in the urine. The urine has a red or brown discolouration

Salt-loving

A hazard is a process, phenomenon or human activity that may cause loss of life, injury or other health impacts

The most prominent clinical signs of equine Horner's syndrome are unilateral drooping eyelid, local sweating and increased cutaneous temperature in the denervated area.

Low levels of oxygen in tissues

At the point of death

This is an inherent characteristic of a particular species of microbe to a particular anti-infective agent.

Invasins are proteins produced by pathogenic bacteria that interact with specific receptors on host cells that allow them to invade host cells.

These are 4 postulates published by Robert Kock in 1890. Due to the multifactorial nature of some diseases, they are no longer validate for all diseases. However, they do provide a good framework for understanding infectious disease.

A enzyme produced by a number of different pathogenic bacteria that breakdown lecithinase, a phospholipid in the cell membrane of cells like red blood cells.

Superficial lymphatic dilatation caused by a wide range of scarring processes

Mastitis is defined as an inflammation of the mammary gland usually in response to a bacterial infection

This refer to bacteria that grow well between 20c to 45 C. Most bacterial pathogens are in this group with an optimum growth temperature of 35C.

Staphylococcus aureus and other staphylococci that have the mecA gene alter their penicillin binding proteins. This is observed as resistance to methicillin (or oxacillin, cefoxitin). These bacteria tend to be multidrug resistant.

Numerous small lesions resembling millet seeds in size and shape

The lowest concentration of an antimicrobial that will inhibit growth of the target microbe.

A mitogen is a substance that induces or stimulates mitosis leading to cell proliferation.

These are both transposons and and insertion nucleotide sequences that often carry gene cassettes of antibiotic resistance genes that can be transferred to bacterial plasmids and chromosomes.

A bacterium that has acquired resistance to at least one antibiotic in 3 or more antibiotic categories is considered to be multidrug resistant

The lowest concentration of antimicrobial required to stop the growth of the least susceptible bacterium in a large bacterial population.

Infection of fly larvae or maggots in living tissue

Infection of the central nervous system by Listeria

Hospital-acquired infections. Clinical signs develop after 72 hours of hospitalisation.

These are often communicable diseases that are either exotic to a country or have serious consequences to animals, animal industries and people. Each Australian State and Territory and the Federal government has a list of these diseases i.e. foot-and-mouth disease.

A disease or disorder that is caused by the work or working conditions. Infectious diseases can also be occupational.

Localised or generalised swelling of the body tissues due to a build up of fluid.

Abnormal posture due to spastic contraction of the extensor muscles of the neck, trunk and lower extremities

Opportunistic pathogens are those that are usually present in the animal or in its environment that only cause disease when the host's resistance to disease has been altered.

These are micro-organisms that only cause disease when given an opportunity i.e. when the host has a weakened immune system or when mucosal or skin barriers are damaged. They are often part of the commensal microflora of the host.

Eating or chewing of bones by herbivorous animals craving phosphorus

Inflammation of the ear. otitis externa is inflammation of the outer ear; otitis media of the middle ear and otitis interna of the inner ear. Clinical signs are characterised by smelly ears, ear scratching and head shaking together with pain vocalisation. Otitis interna can result in neurological defects such as circling and a head tilt.

Resistance to every class used to treat these bacteria

Parenteral describes any drug administration other than oral

The causative agent of a disease

the ability to cause disease

Pathognomonic is a clinical sign or lesion that is indicative of a particular disease. Its presence is diagnostic for that disease.

A beta-lactam class of antibiotics that inhibit bacterial cell-wall synthesis

Pin-point round red to purple spots in the skin and other tissues caused by haemorrhaging.

Effects of drugs and their mechanism of action

Movement of drugs within the body

Observable or expressed antimicrobial resistances

It is bactericidal and inhibits bacterial cell wall biogenesis by inactivating the enzyme MurA responsible for linking the building blocks of peptidoglycan

A phylogenetic tree represents the evolutionary relationships among organisms. This is mainly via genetic relatedness, but physical characteristics are taken into account.

A point mutation occurs in a genome when a single base pair is added, deleted or changed.

These are substances when ingested cause disease.

A polymer produced by bacteria from the amino acid glutamic acid. It protects B. anthracis from Complement mediated opsonisation. It is a major component of the Japanese fermented food natto. It binds heavy metals like lead when used in ultrafiltration membranes.

Excessive and frequent drinking of water

Two of more bacterial species are present in an infection

Frequent and excessive urination, often goes together with polydipsia

Personal protective equipment. This includes, gloves, mask, safety glasses, face shields, boots etc.

Probiotics are live non-pathogenic microorganisms that are administered in large numbers to promote a healthy intestine.

The likely outcome or course of a disease;

This is when a false membrane, consisting of inflammatory cells and exudate and necrotic cells forms on the surface of the colon. Initially the lesions appear as nodules but then coalesce.

Pus causing. Pus is an exudate consisting of necrotic cells, neutrophils and other inflammatory cells, inflammatory products, and if infectious bacteria or fungi.

This is a chronic inflammatory lesion characterised by the presence macrophages and neutrophils

A quarantine is a restriction on the movement of people, animals and goods which is intended to prevent the spread of infectious agents or pests

Cell-to-cell communication by bacteria through the production of signaling molecules known as autoinducers.

An infectious or parasitic agent that is transmitted from humans to animals

Is an ansamycin that inhibits bacterial DNA-dependent RNA synthesis by inhibiting bacterial DNA-dependent RNA polymerase

This is an infection with a second infectious agent whilst an individual is being treated for the primary or first pathogen. A classic example is a horse that develops upper respiratory tract infection caused by equine herpesvirus and a week later develops a snotty nose due to Streptococcus equi subsp. zooepidemicus.

Presence of bacteria and their toxins in the bloodstream

The protein-rich component of blood after it has clotted.

Swine dysentery is a large intestine disease caused by the anaerobic spirochaete bacterium Brachyspira hyodysenteriae

Presence of proliferating bacteria in the bloodstream just prior to death.

These are microorganisms that grow at high temperatures, usually between 41 to 122 C. Intestinal Campylobacter species are examples of thermophilic bacteria that grow at 42C.

The process the cell uses to make a RNA copy of a piece of DNA. This is knowns as messenger RNA and will be used as a template for the ribosomes to manufacture proteins.

This is when "foreign" DNA is introduced into a bacterium by a bacterial virus known as a bacteriophage.

Often called delayed-type hypersensitivity as it takes 1 to 3 days to develop.This response involves the interaction of T cells, and macrophages.

Inflammation of both the caecum and colon

Presence of excessive urea, a breakdown product of protein, in the blood

World Organisation for Animal Health. A global organisation that disseminates information on animal diseases, especially those that impact on trade and public health.

An infectious or parasitic agent which can be transmitted to humans from animals.