Abstract:
The food compositions for pigs contain calcium peroxide. Calcium peroxide is administered to the pigs via the oral route in a proportion of 0.02 to 1.3 % by weight of the total food ration. 
     The percentage of lean meat and the quality of the carcasses are thus substantially improved.

Description:
BACKGROUND OF THE INVENTION 
     The invention relates to food compositions for pigs. It also relates to a process for the feeding of pigs. 
     A fundamental problem in the rearing of pigs for meat is to ensure their rapid growth while avoiding excessive fatty deposits. This problem is partially solved by taking care to keep the animals in good health, in vaccinating them and, where necessary, administering bactericidal agents such as antibiotics, and in supplying them with a suitable diet. The latter consists mainly of cereals with suitable additions of proteins and minerals. In this way daily weight increases of 500 to 700 g can be obtained during fattening. However, the mean quality of pig carcasses fed in this way still leaves much to be desired. 
     SUMMARY OF THE INVENTION 
     The present invention therefore aims to obtain food compositions for pigs which provide an increase in the percentage of lean meat and an improvement in the quality of the carcasses. These compositions also provide particularly high daily increases in weight during fattening. 
     The invention therefore relates to food compositions for pigs which contain calcium peroxide. 
     DETAILED DESCRIPTION OF THE INVENTION 
     The calcium peroxide present in the compositions according to the invention can be of any known grade. In general a commercial product is used. Commercial products in general contain from 30 to 90% of calcium peroxide, the remainder comprising various compounds such as calcium oxide, hydroxide or carbonate or water and are in the form of particles. Other grades of calcium peroxide can also be suitable. 
     The calcium peroxide is in general introduced into the food compositions according to the invention in proportions such that the ration of peroxide ingested daily is at least 0.02% and preferably at least 0.05% of peroxide (100%) with respect to the weight of the total food ration. In general these proportions are such that the ration of peroxide ingested daily does not exceed 1.3% and preferably 0.7% of the weight of the total food ration. 
     The compositions according to the invention can be in the form of a complete food. Thus, they can consist mainly of one or more food substances for pigs such as cereals (barley, maize, oats, wheat, sorghum, soya, rye, millet) and oilseed cakes. The complete food compositions according to the inventon can also contain small quantities of additives usually present in compositions of this type such as inorganic salts, vitamins, trace elements, amino acids, flavourings, binders and antibiotics or other bactericidal agents. 
     The complete food compositions according to the invention can be in different physical forms for example in the form of compacted tablets, granules, powders or even in semi-liquid form. 
     The compositions according to the invention can also be in the form of an addition to the normal feed. In this case, they can consist mainly of calcium peroxide or again contain in addition to the calcium peroxide, various other additives such as vitamins, inorganic salts, trace elements, amino acids, flavouring products and binders as well as certain active substances suited to the specific needs of the animal. These additions can be in different physical forms (powders, compacted tablets, or granules and if necessary in liquid or semi-liquid form) and can be given to animals in the form of a ration separate from the feeds. They can also advantageously, be mixed at the moment of use with the food rations. Such compositions of food additives contain in general from 5 to 90% and most often from 10 to 60% by weight of calcium peroxide. 
     The invention also relates to a process for the feeding of pigs according to which calcium peroxide is administered to them by the oral route. The quantities administered are in general such that the ration ingested daily is from 0.02 to 1.3%, and preferably from 0.05 to 0.7%, of the weight of the total food ration. These quantities can be administered daily over any period and even throughout the life of the animal. 
    
    
     In order to illustrate the invention without, however, restricting its scope, some practical examples of application are given below. 
     EXAMPLE 
     Three batches of 15 male pigs castrated two months before, in good health and with a mean weight of around 30 kg were used (batches I to III). They were placed in sties in groups of five animals of comparable weight. The animals were raised under excellent sanitary conditions. 
     The fattening period was 3 months. Throughout this period the animals received, ad libitum and to the exclusion of any other food, a dry flour for pigs of type 29, sold by INTERAGRI, of 0.95 fodder units and of good bacteriological quality, containing 16.2% of proteins and having an energy content of 9200 kJ/kg and made up with 0.01% to 100% CaO 2  (batch I, groups 1 to 3), 0.3% of 100% CaO 2  (batch II, groups 4 to 6) and 0.6% of 100% CaO 2  (batch III, groups 7 to 9), as well as with calcium carbonate in order to provide a calcium to phosphorus weight ratio of 1.3 in all cases. 
     The calcium peroxide was used in the form of a product containing 75% of CaO 2 . 
     The fattening performance by group of pigs is shown in Table I below. The index of consumption (Ic) represents the total consumption by weight of food in relation to the gain in weight over the full period of the test. 
     
                                           TABLE I__________________________________________________________________________Batch      Batch I     Batch II    Batch IIIGroup      1  2  3  mean                  4  5  6  mean                              7  8  9  mean__________________________________________________________________________CaO.sub.2 (100%) content      0,01        0,3         0,6in the food rationInitial weight, kg      24,8         27,9            30,3               27,7                  25,1                     28,0                        30,3                           27,8                              24,8                                 28,1                                    30,5                                       27,8Final weight, kg      93,1         91,4            94,3               92,9                  95,5                     94,6                        93,4                           94,5                              89,8                                 95,3                                    92,1                                       92,4Growth, g/day       740          706             717                721                   745                      732                         693                            723                               654                                  706                                     733                                        698Consumption, kg/day      2,65         2,55            2,69               2,63                  2,57                     2,70                        2,78                           2,68                              2,40                                 2,61                                    2,93                                       2,65Ic         3,58         3,61            3,75               3,65                  3,45                     3,69                        4,01                           3,72                              3,68                                 3,69                                    3,99                                       3,79Fattening time, days      92,2         90,0            89,3               90,5                  94,5                     91,0                        91,0                           92,2                              99,4                                 95,2                                    84,0                                       92,9__________________________________________________________________________ 
    
     After around three months, 41 animals were slaughtered including 13 from batch I and 14 from each of batches II and III. The carcasses were classified according to the EEC standard according to which the letters below have the following meanings: 
     AA: very good meat pig 
     A: meat pig 
     B: average meat pig 
     I: pork pig 
     II: semi-bacon pig 
     III: bacon pig. 
     The distribution of the pigs by category in each batch and the mean price obtained on sale per batch are given in Table II. 
     
                       TABLE II______________________________________Category     Price per kg                No. of carcassesEEC       in Belgian Batch     Batch BatchClassification     francs     I         II    III______________________________________AA        65,0       --        --    3IA        60,0       4         7     3IB        56,5       5         3     4IIA       56,0       3         3     3IIB       50,5       1         1     1Average price of batch            57,0      57,71   58,53Belgian francs per kg______________________________________