Commission Regulation (EC) No 429/2008Show full title

1.4. Section IV: studies concerning the efficacy of the additive

Technological additives are intended to improve or stabilise the characteristics of feed but have generally no direct biological effect on animal production. Evidence of the efficacy of the additive must be provided by means of appropriate criteria as reflected in recognised acceptable methods, under the intended practical conditions of use in comparison with appropriate control feed.

Efficacy will be assessed by in vitro studies, with the exception of substances for control of radionuclide contamination. The appropriate end-points are indicated in the following table for the various functional groups.

End-points for different technological additives

Functional group	End-points for demonstration of efficacy
(a) Preservatives	Inhibition of microbial growth, particularly that of biotic and spoilage organisms. The period for which a preserving effect is claimed shall be demonstrated.
(b) Antioxidants	Protection against oxidative damage of key nutrients/components during feedingstuff processing and/or storage. The period for which a protecting effect is claimed shall be demonstrated.
(c) Emulsifiers	Formation/maintenance of stable emulsions of otherwise immiscible or poorly miscible feed ingredients.
(d) Stabilisers	Maintenance of the physico-chemical state of feedingstuffs.
(e) Thickeners	Viscosity of the feed materials or feedingstuffs.
(f) Gelling agents	Formation of a gel resulting in a change in the texture of the feedingstuff.
(g) Binders	Pellet durability or performance of pellet formation.
(h) Substances for control of radionuclides	Evidence of reduced contamination of food of animal origin.
(i) Anti-caking agents	Flow ability. The period for which an anti-caking effect is claimed shall be demonstrated.
(j) Acidity regulators	pH and/or buffering capacity in feedingstuffs.
(k) Silage additives	Improved production of silage; Inhibition of undesirable micro-organisms; Reduction of effluents; Improved aerobic stability.
(l) Denaturants	Indelible identification of feed materials.

Silage additives

Separate tests shall be made to demonstrate the effect requested on ensiling process(1). The trials shall be performed with one example of each of the following categories (where all or unspecified forages are involved):

• easy to ensile forage: > 3 % soluble carbohydrates in fresh material (e.g. whole plant maize, ryegrass, brome grass or sugar beet pulp),

• moderately difficult to ensile forage: 1,5—3,0 % soluble carbohydrates in the fresh material (e.g. meadow grass, fescue or wilted alfalfa);

• difficult to ensile forage: < 1,5 % soluble carbohydrates in the fresh material (e.g., orchard grass or leguminous plants).

Where requests are restricted to sub-categories of forage described in terms of dry matter (DM), the dry matter range shall be explicitly stated. Three tests shall then be made with material representative of the range, where possible using examples of different botanical origin.

Specific tests are required for the particular feedingstuffs.

The duration of the study normally shall be 90 days or longer at a constant temperature (recommended range 15—25 ^oC). Use of a shorter duration must be justified.

As a rule measurements of the following parameters shall be provided in comparison to the negative control:

• dry matter and calculated dry matter losses (corrected for volatiles),

• pH- decrease,

• concentration of volatile fatty acids (e.g. acetic, butyric and propionic acids) and lactic acid,

• concentration of alcohols (ethanol),

• concentration of ammonia (g/kg of total nitrogen), and

• content of hydro-soluble carbohydrates.

In addition, other microbiological and chemical parameters shall be included as appropriate to substantiate the specific claim made (e.g. numbers of lactate assimilating yeasts, numbers of Clostridia, numbers of Listeria and biogenic amines).

An effect sought for effluent reduction will be judged against the total volume of effluent produced over the entire experimental period, taking into account the likely effect on the environment (e.g. ecotoxicity of the effluent or biological oxygen demand). Reduction of effluent production shall be demonstrated directly. The capacity of the silo shall be sufficient to allow effluent to be released with the application of pressure. The duration of the study shall normally be 50 days. If a different period is used, this shall be justified.

Improved aerobic stability shall be demonstrated in comparison with a negative control. Stability studies shall be of at least seven days duration after exposure to air and additive shall provide evidence of stability for at least two days longer than that shown by untreated control. It is recommended that the experiment is made at an ambient temperature of 20 ^oC and a rise in temperature of 3 ^oC or more above background taken as indicative of instability. Temperature measures may be replaced by measurement of CO₂ production.

(1)

For purpose of this Regulation, ‘ensiling process’ means process by which natural deterioration of organic matter is controlled by acidification in anaerobic condition resulting from natural fermentation or/and addition of silage additives.