Abstract:
Covers a method of accelerating the growth of animals by incorporating anhydroerythromycin in their feed. Also covers a feed composition containing said anhydroerythromycin.

Description:
DESCRIPTION OF THE INVENTION 
     Successful animal husbandry is contingent upon the rapid development and growth of the animal. The shorter the period of development can be made, the larger will be the return and margin of profit. The quicker that they can be grown to the proper size and sold in the marketplace, the higher the profit margin. 
     It has been found here that the growth of animals can be accelerated by providing in the various commercial animal feed compositions anhydroerythromycin. Addition of the compound causes an increase in weight and growth. The anhydroerythromycin compound may be used to accelerate the growth of a wide variety of animals such as pigs, chickens, turkeys, cattle, etc. 
     Anhydroerythromycin is a known compound having the following structure: ##STR1## 
     Its formation from erythromycin A is described, for example, in Experientia 27, 362 (1971). 
    
    
     The following examples are given to illustrate the invention but it should be understood that they are not intended to limit the invention in any way. 
     EXAMPLE I 
     In this experiment pigs averaging 9.5 lb. at the start were fed anhydroerythromycin in their basal ration and compared to littermate control groups which did not receive anhydroerythromycin. In the specific experiment there were a total of six replications in both the control group and treated group with four pigs per treatment in each replication. The experiment was carried on for 28 days. 
     Table I sets forth the basal rations used in the treatment. Five pounds of basal ration I was employed in the treatment followed by basal ration II for the remainder of the treatment. 
     
                       TABLE I______________________________________Ingredient    I               II______________________________________Ground Corn Yellow         25.0            49.0Solv. SBM (50%prot.)        20.0            20.0Dried Whey (highlactose)      10.0            15.0Dried Skim Milk         30.0            5.0Dried Beet Pulp         2.5             --Sucrose       5.0             25Stabilized Lard         2.5             2.5Calcium Carbonate         0.2             0.5Dicalcium Phosphate         0.3             1.0Iodized Salt  0.5             0.5Trace MineralPremix        2.0.sup.a       2.0.sup.aVitamin Premix         2.0.sup.b       2.0.sup.bTOTAL         100.0           100.0         Calculated AnalysisProtein, %    24.00           18.10Calcium, %    0.68            0.69Phosphorus, % 0.61            0.60Vit. A, I.U./lb.         3,000.00        3,000.00Vit. D, I.U./lb.         600.00          600.00Riboflavin, mg./lb.         8.30            6.70Pantothenic Acid,mg./lb.       18.30           16.10Niacin, mg./lb.         26.80           26.30Choline, mg./lb.         767.00          726.00Vit. B.sub.12, mcg./lb.         20.00           20.00______________________________________ .sup.a Contributed the following per 100 lb. of diet: 5.6 gm. Mn; 1.8 gm. Fe; 180 mg. Cu; 60 mg. Co; 110 mg. I; 4.6 gm. Zn .sup.b Contributed the following per 100 lb. of diet: 300,000 I.U. vit. A 60,000 I.U. vit. D; 400 mg. riboflavin; 1 gm. pantothenic acid; 2 gm. niacin; 20 gm. choline; 2 mg. vit. B.sub.12 
    
     Results of this experiment are shown in Table II. It can be seen that pigs receiving anhydroerythromycin gained faster and required less feed per unit of gain than pigs receiving just the basal ration. 
     
                       TABLE II______________________________________Anhydroerythromycin, gm./ton            0           20______________________________________ADG*, lb.Rep. 1               0.58        0.512                    0.47        0.493                    0.37        0.424                    0.46        0.585                    0.30        0.466                    0.29        0.47AV.                  0.41        0.49F/G**Rep. 1               1.85        1.852                    2.17        2.313                    2.24        2.074                    1.90        1.865                    2.49        1.956                    2.48        210AV.                  2.19        2.03______________________________________ *Average Daily Grain **Feed Required Per Lb. Gain 
    
     EXAMPLE II 
     Here again pigs were treated as in Example I employing the same basal rations. Results as shown in Table II again demonstrate the efficacy of anhydroerythromycin in enhancing weight gain compared to the control. 
     
                       TABLE III______________________________________Anhydroerythromycin, gm./ton            0           10______________________________________ADG*, lb.Rep. 1               0.59        0.742                    0.62        0.903                    0.72        0.754                    0.56        0.655                    0.51        0.496                    0.63        0.66AV.                  0.60        0.70F/G**Rep. 1               2.03        2.112                    1.99        1.893                    1.76        1.884                    1.85        1.765                    1.91        1.796                    1.84        1.85AV.                  1.90        1.88______________________________________ *Average Daily Gain **Feed Required Per Lb. Gain 
    
     EXAMPLE III 
     Here White Rock day-old cockerels were employed to determine the growth stimulant properties of anhydroerythromycin. Each treatment group consisted of four replicates with six chicks alloted to each replicate. The basal diet is shown in Table IV. 
     
                       TABLE IV______________________________________Ingredient        %______________________________________Sucrose           60.4Casein (Crude) +small % of Vit. Free             20.0Gelatin           8.0Calcium gluconate . H.sub.2 O             5.0Salt mixture*     2.25Tricalcium phosphate             1.75Vitamins in dextrose**             1.0Cystine-L         0.4Choline chloride  0.2Corn oil          1.0             100.0             Gms. per*Salt Mixture     100 gms. dietSodium chloride   0.600Dipotassium phosphate             0.600Monopotassium phosphate             0.450Magnesium sulfate. H.sub.2 O             0.250Manganese sulfate 0.038Ferric citrate    0.050Copper sulfate    0.002Potassium iodide  0.0006Zinc sulfate      0.015Cobalt (ous) chloride             0.0004(CoCl.sub.2. 6H.sub.2 O)Sodium molybdate  0.00005             Gms. per**Vitamin Mixture 100 gms. dietThiamine hydrochloride             0.001Riboflavin        0.001Niacinamide       0.005Pyridoxine        0.001Calcium pantothenate             0.005Folic acid        0.0005Klotogen F (Vit. K)             0.0005Biotin            0.00002Vitamin B-12      0.000005Vitamin A (Dawes) 1,500 unitsVitamin D-3 (Dawes)             201 unitsVitamin E (Myoamix)             10 mg.______________________________________ 
    
     Chicks treated just with the basal diet had an average weight gain of 266 g. in four weeks. Chicks whose basal diet also contained anhydroerythromycin had an average weight gain of 319 g. in four weeks or a 20.1 percentage increase over control. 
     It should be understood that this invention is meant to include the administration of anhydroerythromycin in forms other than as a solid in feed mixes. Thus, for example, the growth of animals can be promoted by adding the anhydroerythromycin to their drinking water. When dispersed in a feed the anhydroerythromycin is normally present in an amount of 2 - 100 g. per ton of feed. 
     The anhydroerytheromcyin may be used with a wide variety of conventional feed ingredients including ground barley, ground wheat, ground kafir and milo, bone scraps, cornmeal, corn gluten meal, cane feeding molasses, condensed fish solubles containing fish liver and grandular products, fish meal, yellow hominy feed, and inorganic mineral salts. Also other feed additives can be incorporated in the feed composition of the invention including D-activated animal sterol (source of vitamin D-3), vitamin B 12  supplement, procain penicillin, riboflavin supplement, calcium pantothenate, niacin, choline chloride, 3-nitro-4-hydroxyphenylarsonic acid, phenylarsonic acid, halogenated phenylarsonic acid, p-hydroxyphenylarsonic acid, the alkaline diamine salts of halo-phenylarsonic acid and arsanilic acid.