Composition for improving the digestibility of feed intended for ruminants

A composition designed for improving the digestibility of feed for ruminants contains as active ingredient an aromatic phenol derivative selected from cresols and benzenediols, as well as an absorbing support and an aromatizing mixture.

FIELD OF THE INVENTION 
The present invention is concerned with a composition for improving the 
digestibility of feed intended for ruminants. In particular, this 
composition can be provided in the form of a concentrated mixture designed 
for incorporation as an additive into the usual feed for ruminants. 
BACKGROUND OF THE INVENTION 
In ruminants, it is important for the digestibility of the feed that the 
organic material (in particular, protein and starch) should not undergo 
too much degradation in the rumen, but that the nutrients be transferred 
into the small intestine in a less degraded form, so that they may undergo 
an enzymic digestion which has lesser energy requirements, since it allows 
an increased production of adenosine triphosphate (ATP). 
SUMMARY OF THE INVENTION 
The purpose of the present invention is to provide a composition. designed 
for incorporation into feed for ruminants and which makes it possible to 
improve substantially the digestibility thereof and, consequently also to 
improve the growth of ruminants receiving such a feed. 
The composition according to the invention aimed at meeting the above 
objective includes as the active ingredient, an aromatic phenol derivative 
selected from cresols and benzenediols. 
Actually, the present inventors have found unexpectedly that the desired 
active effect on digestion was obtained by using an aromatic phenol 
derivative, and more particularly a cresol or a benzenediol, and specially 
resorcinol (m-benzenediol), or a mixture thereof. 
Furthermore, they have also found that the transfer of nutrients, which had 
undergone less degradation into the small intestine thanks to the 
composition according to the invention, had another advantage in milking 
cows, namely a reduction in nitrogenous toxins produced by microbial 
degradation, which toxins provoke an inflammation of the udder. This 
inflammation is countered by an immunological reaction with the effect of 
an important increase in the milk of leukocytes called "somatic cells". 
Actually, these somatic cells cause problems in cheese making and for this 
reason, milks containing high levels of somatic cells are paid less to the 
farmer.

DETAILED DESCRIPTION 
Preferably, the aromatic phenol derivatives are incorporated into the 
animal feed so that their intake be approximately of 1 to 100 mg per 
animal and per day, depending on the weight of said animal. 
The compositions according to the invention intended for incorporation into 
standard animal feed can include an absorbing support and an aromatizing 
mixture, to which the active ingredient is added. For instance, the 
proportion may be as follows: 
5 to 10% of the phenol derivative, 
20 to 30% of an aromatizing mixture, 
and from 60 to 75% of an absorbing support. 
Concerning the phenol derivative, use is preferably made of eresol or 
resoreinol or of a mixture thereof, for example a mixture containing 60 to 
90% cresol and 10 to 40% resoreinol. 
For example, one can use the following mixtures of absorbing support and of 
aromatizing mixture. 
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(a) Absorbing support: 
Sterilized fir tree sawdust 
40-50% 
Stearin 8-10% 
Curcuma powder 4-5% 
Rosemary powder 4-5% 
Limestone 22-28% 
Arabic gum approx. 2% 
Water approx. 10% 
(b) Aromatizing mixture: 
Thymol 25-35% 
Guaiacol 10-15% 
Eugenol 5-10% 
Vanillin 10-20% 
Salicylaldehyde 5-10% 
Limonene (solvent) 20-35% 
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In practice, the cresol and/or the resoreinol are added to the liquid 
aromatizing mixture, then this new mixture is incorporated into the 
absorbing support, for example in a flour mixer. 
In principle, for the administration to the animals, the composition 
according to the invention must be diluted, such a dilution being 
generally carried out in two steps; in the first one, a concentrated 
mixture or premix is prepared in which the composition according to the 
invention is diluted to 0.5-5% and this premix is in the second step mixed 
into an animal feed of the usual type. 
For example, the concentrated mixture or "premix" can have the following 
composition: 
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Composition according to the invention 
0.3-3% 
Vitamin mixture (A, B, D, E, niacin, etc) 
0.1-1% 
Mineral salts (CaHPO.sub.4, CaCO.sub.3, NaCl, CuO, MnO, 
25-75% 
FeSO.sub.4, ZnO, etc) 
Wheat middlings and brans 21-75% 
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Again and merely by way of example, the above-mentioned premix can be 
incorporated into a feed to yield the following preparation: 
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Premix according to the invention 
0.3-3.5% 
Cereals and peas approx. 50% 
Oilmeal (soya, rape, etc) 
approx. 25% 
Wheat middlings and brans 
21-25% 
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Such a feed, containing the composition according to the invention and 
given in the amount of 2 to 10 kg per day per animal, provides daily doses 
of 5 to 100 mg of cresols and of i to 50 mg of benzenediols. 
To demonstrate the efficacy of the composition according to the invention, 
three trials were carried out respectively to elucidate the effects in the 
rumen, on the occurrence of somatic cells in the milk and on the growth of 
the animals. 
Trial 1: effects in the rumen 
This trial was carried out according to the "in vitro" technique of Menke, 
using for the incubation: 
(a) a feed containing 
30% dried maize silage 
25% dehydrated hay 
15% barley 
12.5 % maize 
17.5% soya seed oilmeal 
(b) the juices from the rumen of three animals with a fistula permanently 
inserted into the rumen; the animals receive feed (a) and the juices are 
sampled in the fasted state, 
(c) Mac Dougall's buffer. 
The incubation is continued during 48 hours at 39.degree. C. and the 
different metabolites representative of the digestibility in the rumen are 
determined after 6 and 48 hours. 
The test is repeated 12 times, on the one hand with the feed only (control) 
and on the other hand with a feed containing the composition according to 
the invention, more particularly a premix containing 10% of a 
cresol--resorcinol mixture (75%-25%), 20% of an aromatizing mixture of the 
type described previously by way of example and 70% of an absorbing 
support also corresponding to that described by way of example. 
The results obtained are given in the following table: 
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Table of results: 
Feed with master 
Control batch of invention 
6h 48h 6h 48h 
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(A) Precipitable protein 
107.88 86.31 133.69 
113.63 
(TCA) (mg/100 ml) 
(B) Ammonia, as nitrogen 
24.19 40.32 4.83 6.75 
(mg/100 ml) 
(C) Total volatile acids 
58.85 188.14 41.46 131.40 
(mg/100 ml) 
(D) Production of gas 
72 122 56 85 
(mg/100 ml) 
(E) Dry substance, degrada- 
-- -- 54.12 41.28 
tion in % of the initial value 
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(A) The higher value for the feed with the premix according to the 
invention indicates that the protein of the feed is better protected. 
(B) The important decrease in ammonia (as nitrogen) demonstrates that the 
protein is better protected and hence undergoes less degradation in the 
rumen. 
(C) The decrease in the total volatile acids indicates that the starch is 
better protected. 
(D) The decrease in the production of gas indicates also that the nutritive 
organic material undergoes less degradation and is hence better protected. 
The results obtained in this test show therefore clearly that in the ease 
of the feed containing the premix according to the invention, the 
degradation in the rumen is decreased, which improves the digestibility of 
said feed. 
Trial 2: effect on the somatic cells of milk 
The test was carried firstly under farm conditions on a herd of 46 milking 
cows of initially excellent sanitary condition. Half the herd (control) 
received as feed a usual one, whereas the other half (trial) received a 
feed supplemented with the premix according to the invention, as it was 
described previously by way of example. After 6 weeks, the number of 
somatic cells of the control group was 113,000/ml of milk, whereas that of 
the control group fell to 99,900/ml of milk. 
Another test was carried out on a herd of 50 milking cows of which the 
initial sanitary condition was average, and which had 395,000 somatic 
cells per ml of milk. After receiving a feed complemented with the premix 
according to the invention, this number decreased as follows: 
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After 1 week 305,000/ml of milk 
After 3 weeks 236,000/ml of milk 
After 5 weeks 219,000/ml of milk 
After 6 weeks 195,000/ml of milk 
After 7 weeks 128,000/ml of milk 
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The above results demonstrate clearly that the composition according to the 
invention makes it possible to reduce considerably the microbial 
catabolism. 
Trial 3: effect on animal growth 
This trial was carried out during 35 days under farm conditions on growing 
cattle. The trial was carried out on two groups of 20 animals, one of 
which (control group) received a standard feed and the other (trial group) 
received a feed complemented according to the invention as described by 
way of example above, in which the amount of active ingredient was 
approximately 100 mg per 3.3 kg of feed. 
The results obtained are as follows: 
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Control group 
Trial group 
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Average initial weight (kg) 
185.7 185.1 
Average final weight (kg) 
227.9 233.0 
Average daily weight increase (g) 
1206 1369 
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The increase found in the growth (+13.5% on the average) can be explained 
by the improvement of the digestibility of the feed given, which is due to 
the incorporation of the composition according to the invention.