3 week old male rats were fed ( a ) a methionine poor ration , ( b ) the methionine poor ration with addition of 0 . 198 % of a 56 . 0 % aqueous sodium methioninate solution , ( c ) the methionine poor ration with addition of 0 . 315 % of a 40 % aqueous potassium methioninate solution , ( d ) the methionine poor ration with addition of 0 . 1 % of solid dl - methionine . the methionine poor ration in each case consisted of the following components : ______________________________________soybean meal 22 . 0starch , dab 6 53 . 0sucrose 10 . 0soybean oil 3 . 0cellulose 4 . 0minerals and trace 6 . 0elements mixturevitamin mixture 2 . 0______________________________________ the 3 week old male rats ( strain siv 50 ) having a weight of about 50 grams were divided into 4 groups of 8 aminals . the aminals were held individually in cages at a room temperature of 21 ° c . (± 1 ° c .). the main experiment ran for 28 days . weight and fodder uptake were determined weekly . the results are presented in table 2 for weight increase and fodder intake : table 2__________________________________________________________________________methionine activity of aqueous sodium methioninateand potassium methioninate solutions with ratsgroup weight ( g ) increase fodder ( each n = 8 ) ration beginning end ( g ) consumed ( g ) __________________________________________________________________________1 methionine poor 50 . 3 154 . 8 104 . 5 435 . 7 basal ration ( br ) 2 br + 0 . 10 % methionine 48 . 3 210 . 0 161 . 7 496 . 2 ( 0 . 198 % of a 56 . 0 % aqueous solution of sodium methioninate ) 3 br + 0 . 10 % methionine 49 . 6 211 . 7 162 . 1 501 . 6 ( 0 . 315 % of a 40 . 0 % aqueous solution of potassium methioninate ) 4 br + 0 . 10 % methionine 53 . 9 216 . 4 162 . 5 508 . 4 ( content 99 . 5 %) __________________________________________________________________________ the results prove that aqueous solutions of sodium or potassium methioninate used according to the invention have the same methionine activity as solid methionine , insofar as equimolar amounts are employed . the effectiveness of an aqueous solution of sodium methioninate ( 51 . 7 %) and an aqueous solution of potassium methioninate ( 37 . 3 %) was tested on male and female chicks of the breed &# 34 ; shaver starbo &# 34 ; in a three week battery experiment . there served as basal ration a crystalline aminoacid diet which contained all nutrients in a fixed calculated needed ( composition and is particularly suited to recognize differences in the effectiveness of added substances ( j . nutr . 110 , 959 ( 1980 )). table 3______________________________________composition of the basal rationbasal ration % amino acid mixture % ______________________________________corn starch 58 . 7 l - arginine 0 . 95corn oil 10 . 0 l - histidine 0 . 33cellulose 3 . 7 l - lysine . hcl 1 . 14amino acid 19 . 5 l - tyrosine 0 . 45mixture l - tryptophan 0 . 15vitamin - mineral 1 l - phenylalanine 0 . 50mixture * l - threonine 0 . 65nahco . sub . 3 1 . 5 l - leucine 1 . 00caco . sub . 3 1 l - isoleucine 0 . 60cahpo . sub . 4 . 2h . sub . 2 o 2 . 8 l - valine 0 . 69k . sub . 2 hpo . sub . 4 0 . 9 glycine 0 . 60nacl 0 . 88 l - proline 0 . 40total 100 l - glutamic acid 12 . 00 total 19 . 46______________________________________ * the vitamin - mineral mixture contained the following ingre - dients per kg fodder : 80 mg thiamine , 100 mg niacin , 16 mgriboflavin , 10 mg d - pantothenic acid , 2000 mg choline chloride , 5 mg pyridoxine , 4 mg folic acid , 0 . 6 mg biotin , 20 mg dl - α - tocopherol - acetate , 100 mg inositol , 2 mg para - aminobenzoicacid , 5 mg menadione , 250 mg ascorbic acid , 0 . 02 mg vitaminb . sub . 12 , 10 , 000 i . u . retinyl acetate , 600 i . c . u . cholecalciferol , 125mg antioxidant , 3500 mg mgso . sub . 4 . 7h . sub . 2 o , 650 mg mnso . sub . 4 . h . sub . 2o , 500mg iron citrate , 150 mg znso . sub . 4 . h . sub . 2 o , 20 mg cuso . sub . 4 . 5h . sub . 2o , 9 mgna . sub . 2 moo . sub . 4 . 2h . sub . 2 o , 9 mg h . sub . 3 bo . sub . 3 , 40 mg ki , 1 mgcoso . sub . 4 . 7h . sub . 2 o , and 2 mg na . sub . 2 seo . sub . 3 . to this basal ration there was added 0 . 4 , 0 . 5and 0 . 6 % of crystalline dl - methionine or the methionine equi - valent amounts of aqueous solutions of sodium methioninate andpotassium methioninate . each test group consisted of 72 animals ( 6 repetitions of 12 animals each ). the animals received thefodder in meal form ad libitum . water was automatically con - tinuously available . measured test criteria were body weight , feed consumption , as well as feed conversion . at the beginning of the experiment the male animals were 5 days old and the female animals 6 days old . the results after 21 days of the experiment are set forth in table 4 . table 4__________________________________________________________________________average weight increase , feed consumption andfeed conversion after 21 days of the experiment increase feed consumption feed conversiontest group ( g / animal ) ( g / animal ) ( kg fodder / kg increase ) __________________________________________________________________________i 0 . 40 % methionine 222 544 2 . 45ii 0 . 50 % methionine 386 741 1 . 92iii 0 . 60 % methionine 484 830 1 . 72iv 0 . 40 % methionine 219 523 2 . 39 ( 0 . 88 % 51 . 7 % sodium methioninate solution ) v 0 . 50 % methionine 368 710 1 . 93 ( 1 . 11 % 51 . 7 % na met . solution ) vi 0 . 60 % methionine 462 796 1 . 74 ( 1 . 33 % 51 . 7 % na met . solution ) vii 0 . 40 % methionine 220 530 2 . 41 ( 1 . 35 % 37 . 3 % potassium methioninate solution ) viii 0 . 50 % methionine 376 729 1 . 94 ( 1 . 69 % 37 . 3 % k met . solution ) ix 0 . 60 % methionine 472 821 1 . 74 ( 2 . 03 % 37 . 3 % k met . solution ) __________________________________________________________________________ the especial advantage of the ration used in example 2 is that differences in the physiological nourishment effectiveness which might possibly exist between different additives can be especially clearly and significantly established . thereby there are judged the performance parameters weight increase , feed consumption , and feed conversion as criteria with agriculturally useful animals . the results show that through the use of aqueous sodium methioninate and potassium methioninate solutions according to the invention the protein value of the fodder is improved in the same manner as through supplementing with equimolar amounts of solid methionine . in no case were significant differences established . the aqueous sodium methioninate and potassium methioninate solutions of the invention can be employed in all mixed fodders in place of solid methionine . thus the aqueous sodium methioninate and potassium methioninate solutions of the invention can be employed in an equimolar amount in place of the dl - methionine in the mixed fodders of table 1 as well as in mixed fodders for any of the animals mentioned above . the entire disclosure of german priority application p 3105009 . 3 is hereby incorporated by reference .
in place of using solid dl - methionine for supplementing mixed fodders there are used sodium or potassium methioninate solutions . in comparison to solid methionine they are more easily dosable and can be more easily homogeneously mixed with the remaining components . employing equimolar amounts they show the same methionine activity as solid methionine .