the energy supplement components of the present invention can be dry fine powders or liquid . the energy supplement can be made by weighing and mixing together the component quantities with up to 25 % by weight distilled water in any equipment suitable for mixing minerals . the mixture is then heated under pressure in an autoclave to between about 30 and about 200 ° c ., preferably between about 90 and about 150 ° c ., at a pressure between about 1 . 0 and about 2 . 0 atm for about 30 seconds to about 48 hours , preferably between about one and about 30 minutes , and then chilled to room temperature . most preferably , the mixture is heated to about 128 ° c . at between about 1 . 0 and about 1 . 5 atm for about 7 minutes , and then chilled to room temperature . the reaction mixture will have a ph ranging between about 2 and about 10 , preferably from about 6 . 0 to about 8 . 5 . a typical formulation is depicted in table 1 , together with the acceptable ranges within which individual components can be varied : the energy supplement of the present invention may also be optionally formulated with alternate carbohydrate sources in accordance with availability and pricing of ingredients . fructose , sucrose , high fructose corn syrup , glucose , lactose , molasses , xylose , and spent sulfite liquor , and other reducing sugars can optionally be used as a carbohydrate source in the formulation . furthermore , the urea , which is a source of nitrogen , may be optionally substituted by glycine , peptone , casein hydrolysates , casein , methionine , and lysine in accordance with availability and pricing of ingredients . in the event the supplement is prepared in a liquid media , resulting in a liquid product , the resulting liquid product can be dried on different matrixes , such as soybean meal , corn meal , silicates ( verixite , vermiculite , etc . ), rice hulls , mill run , ground corn , citrus pulp , oats hulls , sorghum grain , wheat mill run , and wheat midds . finally , naoh may be used as an alternative to sodium bicarbonate , k 2 hpo 4 , and kh 2 po 4 as a buffer . the energy supplement of the present invention may be conveniently fed to a ruminant admixed with a conventional ruminant feed . feeds are typically vegetable materials edible by ruminants , such as grass silage , corn silage , legume silage , legume hay , grass hay , corn grain , oats , barley , distiller &# 39 ; s grain , brewer &# 39 ; s grain , soya bean meal , and cotton - seed meal . concentrates or grains are preferred . for ruminant animals weighing over 500 kg ( e . g ., young or adult cows ), between about 350 and about 2000 grams a day of the energy supplement should be administered , preferably between about 750 and about 1250 grams , and more preferably about 1000 grams . for ruminant animals weighing between about 80 kg and about 300 kg ( e . g ., young or adult sheep ), between about 250 and about 750 grams should be administered , preferably about 500 grams . for ruminant animals weighing under 150 kg ( e . g ., young or adult goats ), between about 50 and about 400 grams should be administered , preferably about 200 grams . with ruminants under heat stress conditions the preferred dose of the product is between about 0 . 3 and about 2 kg of the product or more typically , between about 0 . 5 and about 1 kg of the product while they are experiencing heat stress conditions . the energy supplements are intended to be fed to ruminant animals on a daily basis . ruminants to which the compositions of the present invention may be fed include cows , goats , sheep , and the like . the period for administration to ruminant animals should be from about one month before calving up to the end of lactation . the preferred administration period for ruminant animals weighing over 500 kg is about one month before calving up to the end of lactation , and more preferably about 20 days before calving to about 30 days after calving . the preferred administration period for ruminant animals weighing between about 80 kg and about 300 kg is about 21 days before calving to the end of lactation , more preferably for about 14 days before calving until about 28 days afterwards . the preferred administration period for ruminant animals weighing under 150 kg is about 14 days before parturition up to the end of lactation , more preferably about 14 days before calving until about 21 days afterwards . rumen degradation evaluation of different rumen protected carbohydrates by measuring ammonia concentration in batch cultures the carbohydrate resistance to ruminal microbial fermentation was estimated indirectly by measuring the concentration of ammonia after incubating the different feed combinations with ruminal fluid in batch cultures ( cleale , j . anim . sci . 1987 , 1312 - 1318 ). the different feed combinations tested are presented in table 2 . the ingredients of each feed combination p1 through p4 were mixed and homogenized , and then autoclaved at 128 ° c . and 1 . 5 atm for 1 , 3 , 7 and 15 minutes . the preparation of pl consisted of autoclaving a mixture of urea , glucose , and the at 128 ° c . and 1 . 5 atm for 1 , 15 and 45 minutes . afterwards , the liquid was mixed with soybean meal and dried for 48 hours at 60 ° c . ruminal contents were extracted from 2 fistulated steers eating a diet consisting of alfalfa hay . ruminal fluid was obtained by filtering the rumen contents through 8 layers of cheese cloth . the fluid was mixed with artificial saliva ( mcdougall buffer ) at a 50 : 50 v / v ratio . temperature was maintained at 39 ° c . and co 2 was used to keep the samples in an oxygen free environment . incubations of the different feed combinations were performed in 250 ml bottles . each bottle had between 1 and 2 grams of a feed combination and was filled with 100 ml of the ruminal liquid and saliva . the bottles were then incubated for 12 hours in a water bath at 39 ° c . all feed combinations were incubated in duplicate . controls , which were feed combinations that were not autoclaved , were also incubated for 12 hours in a water bath at 39 ° c . incubations were terminated by injecting 10 ml of hcl 80 % 16 n and 20 % distilled water . the bottles were removed from the water bath and kept at 4 ° c . until they were centrifuged at 7 , 000 g . the supernatant was analyzed for ammonia concentration ( see broderick and kang . j . dairy sci . 1980 , 63 : 64 ). results : p3 and pl are the carbohydrates based energy supplements that show less ammonia release at all temperatures , and consequently less microbial degradation in the ruminal fluid ( fig1 ). true metabolizable energy ( tme ) in vivo determination of pre - selected rumen protected carbohydrates in order to determine how different manufacturing conditions may affect true metabolizable energy , the feed supplement combinations with the least microbial degradation in experiment 1 , which are combinations p3 and pl , are tested according to the method as described by sibald , i . r ., poultry . sci . j . 1976 ( 55 ): 303 - 308 . the composition of the feed combinations are is shown in table 1 ( example 1 ). thirty - five adult leghorn cocks were used in a completely randomized 2 × 3 factorial design with 5 repetitions . the cocks were fasted for 24 hours and placed in individual cages . each cock received a mix of each test feed combination in a 50 : 50 w / w mix with water . the mix was fed into the beak of the bird using a syringe and a catheter . total excreta of the cocks were collected 48 hours after feeding and were dried in an oven at 60 ° c . for 48 hours . the dried ex - creta was grounded and molded into a tablet . the tablet was then used to determine gross energy . test feed processing times are shown in table 3 ( example 2 ). in order to evaluate the impact of applying temperature and pressure in a buffered environment to a rumen protected carbohydrate ( rupca ) mix with urea and solvent soybean meal fed to holstein dairy cows for the first 28 days after calving . far - off dry cows were fed the same diet from 3 weeks before to the expected calving date . from calving to 28 days in milk ( dim ), 27 multiparous holstein dairy cows were assigned to three treatments in a complete randomized block design with covariance analysis to evaluate the effects of feeding the rumen protected carbohydrate on dry matter intake ( dmi ), lactation performance ( milk yield and composition ), body weight ( bw ), body condition score ( bcs ), milk ketone bodies , and blood glucose . the three treatments were based on 2 kg / cow / d of a mix consisting of carbohydrate , urea and solvent soybean meal ( about 11 % of total dmi ). cows in t0 received 2 kg of 100 % non rumen protected carbohydrate . cows in t1 and t2 were fed with the same amount as t0 cows , but 50 % of supplement mix contained rumen protected carbohydrates ( rupca ) in t1 , and 100 % contained rupca in t2 . the only dietary differences between treatments consisted on the supplied amount of rupca . the cows from each treatments were assigned to different pens replicated twice with 5 and 4 cows each and group fed from one to 28 dim . the dmi was estimated daily by dividing the total intake of each pen by the average dim of the cows in the pen giving a total of 168 observations ( 28 days * 3 treatments * 2 repetitions ), or 56 per treatment . all dietary ingredients in the three treatments were identical , diets components (% dm ) were : 31 . 4 % corn silage , 19 . 4 % alfalfa hay , 22 . 8 % corn grain , 7 . 4 % soybean seeds , 4 % soybean meal , 6 . 3 % solvent soybean meal , 4 % carbohydrate , 0 . 4 % urea and 4 . 3 % minerals & amp ; vitamins . diets were managed as total mixed rations ( tmr ), weekly samples of tmr were taken for nutrient contents . milk yield and composition per cow was measure two times per week on non - consecutive days ( 4 weeks * 2 samples / week = 8 data / cow ). body weight , bcs , and blood glucose were taken once a week . milk yield per cow were compared in kg / cow / d and mcal net energy in milk / cow / d . the mcal en in the milk was calculated based on milk components ( fat , protein , and lactose contents ) according to the nrc ( 2001 ). the statistical analysis model included the fix effect of treatments , weeks , co - variables , and the random effects of cow determinations . orthogonal contrasts were also used to evaluate treatments effects . significance was declared at p & lt ; 0 . 05 and tendencies were considered at 0 . 05 & lt ; p & lt ; 0 . 10 . results : the post - partum dmi from day 1 to day 28 were no different among treatments and averaged 19 . 0 , 20 . 2 , and 21 . 1 kg dm / cow / day for t0 , t1 and t2 respectively . the estimated mean diet nutrient composition was 50 % dm , 16 . 1 % cp , 33 . 8 % ndf , 6 . 1 % fat , and 7 . 5 % ash . the results of milk yield , milk composition , bw , bcs , milk ketone bodies and glucose are presented in table 5 . high sem were observed for milk yield and bw changes . no differences were observed when milk yield was expressed in terms of total milk net energy output . two variables related to fresh cows energy metabolism were affected by the treatments . lactose milk content , which is supported by non - fat solids in milk and glucose concentration in blood were increased by rupca supplement . the values , including weekly estimations of body weight changes , suggest that carbohydrate in the rupca was protected against rumen degradation increasing the glucose supply to treated cows in t1 and t2 .
a method of preparing rumen - protected carbohydrates for use in ruminant feeds by inducing the maillard reaction between a reducing carbohydrate source and a protein source . products made by the process and methods for maintaining or restoring blood glucose levels within the normal reference range for ruminants , especially during transition or under heat stress are also disclosed .