DE2802397C2 - Feed mixture containing carbadox and proteolytic enzymes - Google Patents

Description

High-performance animal feed, as commonly used in intensive animal husbandry today, contains a number of additives with a prophylactic and/or nutritional effect. These include antibiotics, growth promoters and enzymes. While the use of antibiotics and/or growth promoters has already become established in all types of compound feed, enzymes are not yet used on a large scale in practice.

The feed mixtures used in modern intensive animal husbandry are generally so optimized in all nutrient components that further improvement does not seem to be possible without further ado. Surprisingly, however, it has been found that even optimally composed high-performance feeds can be further improved in terms of feed utilization and/or the weight gain that can be achieved with them if certain growth promoters are added to these feeds together with proteolytic enzymes.

The use of growth promoters is well known to experts working in the feed sector. For example, the growth promoter carbadox is already mentioned in the feed regulations of the Federal Republic of Germany of 16 June 1976, Annex 3, Part 1, Paragraph 1.2. Despite the beneficial effects of this substance, there is a need for feeds that can achieve even more beneficial results.

The subject of the older patent application according to DE-OS 27 55 126 is an animal feed mixture based on carbohydrates, protein, fats and optionally conventional additives, characterized by a content of 5 - 350 ppm of the growth promoter Nitrovin and such an amount of proteolytic enzymes that an enzymatic activity of 0.05 - 2.5 mTU/g is present.

It was found that high-quality animal feed mixtures with corresponding growth-improving effectiveness are obtained if the growth promoter of the earlier application is replaced by the growth promoter Carbadox.

The invention accordingly relates to a feed mixture based on carbohydrates, protein, fats and optionally conventional additives and containing 5 - 350 ppm carbadox, characterized in that proteolytic enzymes are additionally contained in such an amount that an enzymatic activity of 0.05 - 2.5 mTU/g is present, where one enzyme unit (TU) is the amount of enzyme which releases cleavage products from a casein solution in one minute which have the same extinction as a 1 mol/l tyrosine solution.

The growth promoter carbadox is produced by chemical synthesis. Its nomenclature-compliant name is: methyl-3-(2-quinoxalinyl-methylene)-carbazate-N[high]1,N[high]4-dioxide. The molecular formula is: C[low]11H[low]10N[low]4O[low]4, the molecular weight is 262.23.

Suitable proteolytic enzymes are mainly obtained by culturing microorganisms and separating them from the nutrient solutions.

The processes for this are known. For example, proteolytic enzymes from Bacillus licheniformis, Bacillus natta, Bacillus subtilis, etc. are used. Acidic proteases, e.g. from Aspergillus niger or from Rhizopus rhizopodiformis according to DE-OS 25 28 490, are particularly preferred. Such proteases have a particularly broad spectrum of activity in the weakly acidic range between pH 2.5 - 6.5.

Commercial feed mixtures are composed as optimally as possible for the specific needs of the individual animal species. The basis is carbohydrates, mainly from grain components, corn or similar. The main sources of protein are soya meal, fish meal, animal meal, bran etc. Missing amino acids, e.g. methionine or lysine, can also be added. Fats are added in the form of vegetable or animal fats or waste fats. Salts such as dicalcium phosphate, calcium carbonate and table salt are also added to build up the body. If necessary, the feed mixture is rounded off by adding trace elements, vitamins, fibre etc. Substances produced by fermentation such as single-cell proteins from petroleum fractions or alcohols, various yeasts, algae protein or other substances, possibly also obtained from waste materials, can also be part of the feed recipe to a considerable extent.

The animal feed mixtures according to the invention contain, in addition to the usual components tailored to a specific animal species, an additional 5 - 350 ppm, preferably 20 - 50 ppm, of the growth promoter mentioned, depending on the age of the animal and the type of feed mixture, and proteolytic enzymes in such an amount that the enzymatic activity is 0.05 - 2.5 mTU/g, preferably 0.2 - 0.5 mTU/g.

The additive concentrations mentioned refer to the content in the entire feed. In concentrates or supplementary feeds, the concentrations are correspondingly higher. In particular, a combination of one of the growth promoters mentioned and an acidic fungal protease or protease mixture is used. The increase or improvement in feed utilization achieved in this way is several percent more than with corresponding control mixtures containing only carbadox.

The claimed combination of carbadox and enzymes is particularly effective in feed for piglet rearing and pig fattening. However, it can also be used in feed mixtures for other animal species in which the growth promoter itself is used to advantage.

The growth promoter is best added to the feed in the form of a premix, e.g. bound to soya meal. When using meal-like feed compositions, the enzyme component is also applied as a premix. Any feed component, e.g. soya meal or an inert carrier, acts as a carrier substance. When using steam-pelleted feed, the enzymes must be added in a suitably stabilized form to prevent deactivation by moisture and heat during pelleting. Such a process is the subject of DE-OS 26 02 260, for example.

To determine the enzyme unit (TU), the proteolytic activity of the protease is determined according to the well-known Anson principle: a suitably diluted amount of enzyme solution is incubated at 40°C for 20 minutes with an equal volume of a 1.2% casein solution containing 0.6% lactic acid, 6 mol/l urea and 0.1 mol/l citric or acetic acid. The pH of the casein solution is adjusted to 4.5 by adding 2 mol/l sodium hydroxide solution. After incubation, 0.4 mol/l trichloroacetic acid is added in a volume ratio of 1:1, the precipitate of undigested casein that forms is filtered off and the protein fragments formed during degradation in the filtrate are determined using any protein determination method. The method described by Layne in Methods in Enzymology 3 (1957), pages 448 ff., is suitable for this.

A blank value must be prepared for each sample, in which trichloroacetic acid and then casein solution are added first. This blank value indicates, in addition to the reagent blank value, the proportion of low molecular weight peptides that are already present in the enzyme solution before digestion. The difference between the main value and the blank value is then compared with the extinction that a certain amount of tyrosine produces in this determination using the specified method. This amount of tyrosine is then a measure of the proteolytic activity of the enzyme in question: one enzyme unit (TU) is the amount of enzyme that releases cleavage products from a casein solution in one minute that have the same extinction as a 1 mol/l tyrosine solution. The usual indication is in mTU = 10[to the power of]-3 TU.

example 1

216 piglets in the weight range from 6.5 kg to 24.8 kg were fed an identically composed rearing feed, but

a) without the addition of carbadox or enzyme,

b) an addition of 50 ppm carbadox or

(c) an addition of 50 ppm carbadox and 0,45 mTU/g feed acid proteases from Rhizopus rhizopodiformis and Aspergillus.

The animals were kept in flat cages of 7 or 8 animals. Feeding was ad libitum. To get used to the new food, all groups were given a starter feed of the same composition. The animals were then given the actual test mixtures (see above).

The growth rate and feed conversion were determined through regular weighing. "Feed conversion" is understood to mean the ratio of feed consumption to growth.

Feed composition (%):

Protein feed, consisting of: 18 %

62.5 % soya meal (44 % crude protein),

25 % fish meal,

12.5% mineral and vitamin premix

Oats 14%

Wheat bran 10%

Barley 28%

Wheat 15%

Corn 15%

_____

100%

Result:

________________________________________________________________________________

a) b) c)

without with with

Additive Carbadox Carbadox

+ Enzym

________________________________________________________________________________

Daily 461 g 526 g 543 g

increase

Feed- 2.11 1.98 1.91

recycling

Example 2

A total of 48 piglets were kept in straw-free conditions on slatted floors from an initial weight of approx. 30 kg in two fattening periods up to a final weight of approx. 100 kg, each with an identically composed feed mixture, which in fattening period I (30 - 60 kg)

a) without the addition of carbadox or enzyme,

b) an addition of 50 ppm carbadox or

(c) an addition of 50 ppm carbadox and 0.6 mTU/g feed acid proteases from Rhizopus rhizopodiformis.

In fattening stage II (60 - 100 kg) the following additive quantities were used in the corresponding groups:

a) without addition of carbadox or enzyme,

b) Addition of 25 ppm Carbadox,

c) Addition of 25 ppm carbadox and 0.3 mTU/g feed acid proteases from Rhizopus rhizopodiformis.

The growth rate and feed conversion were determined through regular weighing. Feed conversion is understood to be the ratio of feed consumption to growth. The animals were fed rationed (twice daily) in accordance with DLG recommendations.

Feed composition (%):

___________________________________________________________________________

Initial mast Final mast

30 - 60kg 60 - 100kg

___________________________________________________________________________

Barley 20 22

Corn 20 22

Wheat 15 22

Oats 15 --

Wheat bran 9 21.5

Fish meal 7 3

Soya meal 12 8

Mineral feed 2 1.5

Result: 30 - 100 kg total mast

________________________________________________________________________________

a) b) c)

without with with

Additive Carbadox Carbadox

+ Enzym

________________________________________________________________________________

Daily 674 g 722 g 753 g

increase

Feed- 3.31 3.18 3.14

recycling

Claims (2)

1. Feed mixture based on carbohydrates, protein, fats and, if appropriate, conventional additives and containing 5 - 350 ppm carbadox, characterized in that proteolytic enzymes are additionally contained in such an amount that an enzymatic activity of 0.05 - 2.5 mTU/g is present, where one enzyme unit (TU) is the amount of enzyme which releases cleavage products from a casein solution in one minute which have the same extinction as a 1 ml/l tyrosine solution. 2. Feed mixture according to claim 1, characterized in that the proteolytic enzymes are acid proteases with an activity spectrum between pH 2.5 - 6.5.