Definition of terms

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V

Name Description Related terms
vaccination
vaccination schedule

The primary and re-vaccination schedules combined.

valid scientific argument
validation

The procedures involved in checking data or programs for correctness, compliance with standards and conformance with the requirement specifications.

In relation to manufacturing of veterinary chemicals, the action of proving, in accordance with the principles of Good Manufacturing Practice, that any procedure, process, equipment, material, activity or system actually leads to the expected result.

value

The quality of a colour, corresponding to tone or reflectance, that, when assigned a numerical value according to its degree of lightness or brilliance, can be used in combination with hue and saturation to identify the colour uniquely.

vaporise

The ability of a chemical to change to a vapour (evaporate).

vaporising mat

A mat made from pulp, or other suitable inert materials, and impregnated with an active constituent. The mat is intended for use in a heating unit designed to produce a slow volatilisation of the active constituent.

The APVMA formulation type code for vaporising mats is MV.

vaporising mats

A mat made from pulp, or other suitable inert materials, and impregnated with an active constituent. The mat is intended for use in a heating unit designed to produce a slow volatilisation of the active constituent.

The APVMA formulation type code for vaporising mats is MV.

vapour drift

The movement of herbicide vapours from the area of application to adjacent areas.

vapour pressure

The saturation pressure above a solid or liquid substance at a particular temperature.

vapour releasing product

A formulated product containing one or more volatile ingredients, the vapours of which are released into the air. The evaporation rate is normally controlled by using a suitable slow-release dispenser or plastic polymer.

variability

Heterogeneity of values over time, space or among different members of a population

variables

A characteristic of a unit being observed that may assume more than one of a set of values to which a numerical classification can be assigned.

Variables can be classified into three categories:

  • independent (input, manipulated, treatment, or stimulus) variables, so called because they are independent of the outcome; instead, they are presumed to cause, effect, or influence the outcome
  • dependent (output, outcome, response) variables, so called because they are dependent on the independent variable; the outcome presumably depends on how these input variables are managed or manipulated
  • control (background, classificatory, or organismic) variables, so called because they need to be controlled, held constant, or randomised so that their effects are neutralised, cancelled out, or equated for all conditions.

 

variables (binary variables)

A variable that identifies the presence or absence of a trait, characteristic, etc.; ‘yes/no’ variables.

variables (binomial variables)

A discrete variable that represents the number of successes out of n (the sample size) identical and independent trials.

variables (continuous variables)

A variable that may take on any value between an upper and lower limit.

variables (discrete variables)
A variable that may take on only certain prescribed values.
variance

A measure of the spread of the values in a distribution. The larger the variance, the larger the distance of the individual cases from the group mean.

vascular system (in plants)

The system of vessels that conducts water, mineral salts and food materials in higher plants.

VCP
vector

An animal able to transmit a pathogen, especially an insect transmitting a virus.

vegetative

Non-sexual (in reference to reproduction).

vegetative buffer

Rows of trees, shrubs or tall grasses planted on the downwind edge of a property to reduce the impact of spray drift on neighbouring sensitive areas. Principles of vegetative buffer design include:

  • buffer width—the wider the buffer, the greater its effectiveness in reducing spray drift
  • buffer height—the buffer should be about twice the height of the spray release
  • buffer distance—the closer the buffer to the release point, the greater its effectiveness
  • type of buffer vegetation—trees or bushes with small or hairy leaves tend to maximise droplet capture.
Venturi spreader (air-scoop)

A device mounted on aircraft wing to replace a blower for breaking up and discharging spray liquids.

very-low-volume spray

A spray application within the range of 10 to 50 litres per hectare (L/ha).

veterinary chemical product

From s.3 of the Agvet Code and has the meaning given by section 5 of the Agvet Code.

veterinary chemical products (definition of when closely similar)

From regulation 1.2 in Schedule 6 to the Agvet Code Regulations.

For a veterinary product to be considered closely similar to a reference product:

  • its active constituent(s) must be the same substance(s)—ie the same APVMA-approved active constituent(s)—as in the reference product and the concentration of its active constituent(s) must be the same as in the reference product
  • its non-active constituents must be the same or equivalent substances as in the reference product and be at the same or equivalent concentrations (Note that minor differences in formulation, specifications, and physicochemical properties may be acceptable if they do not have adverse implications for product quality or biological activity such as efficacy, safety or residues. Efficacy, safety or residues data will not be required to demonstrate similarity of the proposed product to the reference product.)
  • its product specifications (release and expiry limits, and test methods) and physicochemical properties (including pH, particle size and crystal form) must all be the same or equivalent as for the reference product
  • its dose form or formulation type must be the same as the reference product, and
  • its use pattern (including target animal species, dose rates, route of administration, withholding periods), label claims and label instructions must all be the same as for the reference product.

 

veterinary ethical drugs

Veterinary drugs that are only available to, or through, a veterinarian.

Veterinary Labelling
veterinary products (definition of when similar)

From regulation 1.3 in Schedule 6 to the Agvet Code Regulations.

For a veterinary product to be considered similar to a reference product:

  • its active constituent(s) must be the same substance(s)—ie the same APVMA-approved active constituent(s)—as in the reference product and the concentration of its active constituent(s) must be the same as in the reference product
  • its non-active constituents must have similar properties to those in the reference product and be in similar proportions (data will be required to demonstrate similarity of the proposed product to the reference product)
  • its dose form or formulation type must be the same as the reference product
  • its use pattern (including target animal species, dose rates, route of administration, withholding periods) and label instructions must all be the same as for the reference product, and
  • its label claims must not exceed or be inconsistent with those of the reference product.
veterinary surgeon

From s. 3 of the Agvet Code:

Means a person who is registered as a veterinary surgeon under the law of a state or territory.

viable or viability

Able to live. When used with reference to seeds, it means able to germinate.

VICH

International Cooperation on Harmonisation of Technical Requirements of Veterinary Medicinal Products. A trilateral (European Union—United States—Japan) program aimed at harmonising technical requirements for veterinary product registration.

Information on VICH Phase I and Phase II environment impact assessments can be found in the VICH website and in the Veterinary—Environment Regulatory Guideline.

violation

An instance where raw agricultural commodities are found to contain residues at a level above those permitted by law (ie exceeding the prescribed maximum residue limit).

violative samples

Samples found to have residues for which no maximum residue limits have been established or with a residue concentration in excess of the prescribed maximum residue limit.

virucidal activity

The capability of a product to produce a reduction in the number of infectious virus particles of relevant test organisms under defined conditions.

virucide

A product that inactivates viruses under defined conditions.

virulence

The degree of measure of pathogenicity.

The ability of an infectious agent to produce pathologic effects. A measure of the degree to which a standard dose of virus is able to inflict disease in a host.

virulent

Strongly pathogenic.

virus

A member of a group of disease-producing agents that are parasitic in plants and animals and unable to multiply outside the host tissues. Viruses are of great agricultural, veterinary and medical importance. Plant viruses are usually spread by insect vectors (eg aphids), but some are spread by contact with plants, while others are readily transmitted during vegetative propagation. Bacteria are also affected by viral infections (eg root-nodule bacteria on legumes are sometimes destroyed).

viruses
viscosity

An ability of a liquid to resist flowing. The higher the viscosity the slower the liquid flows.

viscous

Describing a liquid that does not readily flow.

volatile

Capable of evaporating or vaporising (changing from liquid to gas) at ordinary temperatures on exposure to the air.

volatilisation

The conversion of a solid or liquid to a gas or vapour by applying heat, reducing pressure, chemical reaction, or a combination of these processes.

A method of redistribution of pesticides between air, soil and water. When the vapour pressure, the water solubility and the soil adsorption or desorption characteristics of a pesticide are known, an estimate can be made whether volatilisation is likely to occur under practical conditions.

volume mean diameter (VMD)

The median particle diameter in a distribution of spray particles, such that half of the volume of spray contains particles greater than the VMD and half the volume contains particles less than the VMD. Also referred to as the volumetric mean diameter.

volume rate

The amount of liquid applied per unit area. For herbicide applications, this may vary from as low as 1 litre per hectare (L/ha) up to 1000 L/ha.

volumetric mean diameter
voluntary recall

A recall that is initiated by the APVMA through the issue of a Voluntary Recall Notice that specifies the actions to be taken to result in an effective recall.