the present invention employs the principal that cpfa can affect the softness of carcass fat in livestock and poultry when fed with a diet supplemented with ufa ( which may include ddgs , even if the ddgs level is over 20 % in the early swine growth phase or over 0 % in the late swine growth phase ). research has shown that feeding cpfa can have effects on the melting point of carcass fat ( it can make the melting point of body fat increase ) which translates to positive taste and texture impacts on the harvested meat , and to more favorable processing and quality characteristics of the carcass . moreover , the inventors have determined that not only the melting point of carcass fat may be affected , but that other carcass characteristics are also improved in the face of ufa supplemented diets , application of ractopamine , or even where the diet is supplemented neither with ufa nor with ractopamine . the present invention provides a method of feeding swine , cattle or poultry a diet comprising a level of ufa ( for example , in the form of ddgs ) higher than the levels typically recommended . ddgs typically contains about 10 % corn oil which is high in ufa . unsaturated fats are preferentially deposited in adipose tissues , leading to soft carcass fat . the diet employed by the present invention comprises between about 20 % to about 40 % and up to about 50 % ddgs containing 10 % corn oil fed with a supplementation of cpfa . the ufa source is not required to be ddgs , though ddgs is used here as a working example of the invention given the prevalence of feeding ddgs to livestock and poultry . the amount of cpfa in this diet falls within the range of between about 0 . 001 % and about 0 . 5 % of the diet . the method of the present invention includes diets that comprise sources of ufa in addition to or instead of those provided by ddgs , includes diets not supplemented with ufa but that include ractopamine , includes diets supplemented with a source of ufa and including ractopamine , and includes diets that are not supplemented with a source of ufa and do not include ractopamine . appropriate diet composition in all cases comprised between about 0 . 001 % and 0 . 5 % cpfa by weight in order to achieve the desired effects . a study was conducted employing five different dietary treatments for grow finish hogs during the six weeks before harvest . pigs were fed a diet containing 7 % ufa and with one of three levels of cpfa for either 4 weeks or 6 weeks before harvest . the treatment levels of cpfa as a percentage of the diet were : 0 . 0375 % cpfa for 4 weeks ; 0 . 075 % cpfa for 4 weeks ; 0 . 0375 % cpfa for 6 weeks , 0 . 075 % cpfa for 6 weeks , and a control without added cpfa for 6 weeks . the study evaluated growth performance , feed disappearance and feed conversion ratio . it measured carcass characteristics including hot carcass weight ( hcw ); 10 th rib backfat depth , adjusted to skin - on basis according to the national pork producers council ( nppc ) ( 2000 ) recommendations ; loin eye area ; and fat - free carcass lean percentage estimated using the nppc ( 2000 ) equation . fatty acid profile and iv of belly fat were obtained by chilling carcasses at 4 degrees c . for 24 hours before collection of belly fat samples . iv of belly fat was calculated using the aocs ( 1998 ) equation : iv =( c16 : 1 × 0 . 95 )+( c18 : 1 × 0 . 86 )+( c18 : 2 × 1 . 732 )+( c18 . 3 × 2 . 616 )+( c20 : 1 × 0 . 785 )=( c22 : 1 × 0 . 723 ). the degree of belly fat firmness was measured by draping the center of the belly over , and perpendicular to , a smoke stick , with the fat side facing down . the lateral ( l ) and vertical ( v ) of the belly flex were measured and used to calculate the flop angle : tan − 1 ( l / v ) where l is one - half the distance between the belly ends while hanging over the stick and v is the vertical distance of belly flex . the specifics of the treatment diets are shown in fig1 . for each of the five treatment groups , fig2 shows the data collected . as can be seen by the data , the diets comprising a higher level of cpfa showed belly flex scores markedly better than for the pigs fed the control diet without cpfa . further , iv score was significantly reduced by the inclusion of cpfa in the diets . a second study was conducted to evaluate the effects of supplementation of cpfa , with and without ractopamine , in a diet containing a high level ( 40 %) of ddgs , on growth performance , carcass characteristics , meat and fat quality in commercial finishing pigs . the experimental diets over a six - week feeding period were a control diet without cpfa and a diet containing 0 . 0375 % cpfa for six weeks ; then for the last three weeks a diet was fed that included ractopamine at 4 . 5 grams per ton for each of the control and cpfa diets . ( see fig4 ). cpfa was added to replace choice white grease in the control diet . as discussed below , no treatment effects on growth performance were observed nor for hcw , dressing percentage or loin muscle , ultimate ph , color or marbling . supplementation of cpfa in late finishing diets significantly changed fatty acid profile and iv of belly fat . it also increased c18 : 0 / c18 : 1 ratio , and increased saturated fatty acids and reduced monounsaturated fatty acids . pig body weight ( bw ) on a pen basis was measured initially and at the end of weeks 3 and 6 to calculate average daily gain ( adg ). on each weigh day , feed disappearance was measured to calculate average daily feed intake ( adfi ) of pigs on pen basis . pen adg and adfi were , in turn , used to calculate feed conversion ratio ( f : g ). pigs were all harvested on the same day and also weighed individually one day before harvest to obtain a final live bw . hcw was measured on carcasses immediately after harvest . live bw and hcw of pigs were used to calculate dressing percentage using the following equation : dressing %=( hcw / live bw )× 100 . backfat ( bf ) and loin depth ( ld ) were measured between the 3 rd and 4 th rib on each carcass using fat - o - meater ( generation ii ). percentage of fat - free carcass lean was calculated by fat - o - meater using the values of backfat depth and loin depth . one barrow and one gilt from each pen weighing closest to the mean bw of their pen were selected for evaluation of meat and belly fat quality . twenty - four hours after carcasses were chilled at 4 ° c ., ph of loin muscle ( lm ) was measured at the 10 th rib using a ph meter . the ph meter was calibrated at the temperature of the lm with ph 4 and 7 buffers . after ph measurement , carcasses were fabricated . loin muscle samples at the 10 th rib were collected for evaluation of meat quality . each lm sample was separated into two equal halves , and vacuum - packaged and frozen at − 20 ° c . until analysis . one section of lm sample was measured for minolta color ( l *: lightness ; a *: redness ; b *: yellowness ), loin purge , chop purge , and instron force ( a measurement correlated with tenderness and chewiness ). japanese color score ( 1 = extremely pale to 6 = extremely dark ; nppc , 2000 ) and marbling score ( 1 = 1 % intramuscular fat to 10 = 10 % intramuscular fat ; nppc , 2000 ) were also determined by trained panelists . the other section of the lm sample was used for sensory evaluation . sensory assessment was performed according to the procedure described by the american meat science association ( 1995 ). samples of lm were thawed at 4 ° c . overnight and cut into chops approximately 1 inch thick . the chops were weighed before and immediately after cooking to determine cooking loss . after cooking , trained panelists evaluated chops for juiciness , tenderness , chewiness , flavor and off - flavor using a 10 - point scale ( 1 = extremely dry , tough , not chewy , none , or none , to 10 = extremely juicy , tender , chewy , intense , or intense , respectively ). in addition to lm , belly core samples at the midline opposite the last rib were also collected from the carcasses for evaluation of fatty acid composition , iv , subjective firmness score , and thickness . each belly fat sample was separated into three equal halves , and vacuum - packaged and frozen at − 20 ° c . until analysis . one section of belly fat samples was analyzed for fatty acid composition using gas chromatography according to aocs ( 1998 ) method ce 1 - 62 . the iv of fat was calculated using the following equation ( aocs , 1998 ): iv =( c16 : 1 × 0 . 95 )+( c18 : 1 × 0 . 86 )+( c18 : 2 × 1 . 732 )+( c18 : 3 × 2 . 616 )+( c20 : 1 × 0 . 785 )+( c22 : 1 × 0 . 723 ). thickness was measured in the middle and edge of another section of belly fat samples . subjective belly firmness score was measured using a 3 - point scale ( 1 = extremely firm to 3 = extremely soft ). to determine the cpfa residue in carcass fat , each of 6 ( 3 barrows , 3 gilts ) belly fat samples from the third section were randomly selected in control and experimental treatments . samples were sent for analysis of individual cpfa using hplc according to the method described by wood ( 1986 ). all data were analyzed using the mixed procedure of sas inst . inc . ( cary , n . c .). pen was used as the experimental unit for all responses . the statistical model included the fixed effects of cpfa , ractopamine , cpfa × ractopamine interactions , and random effect of block . live bw before harvest and sex were used as the covariates in analysis of carcass characteristics , meat and fat quality , if the effects of these covariates were significant ( p & lt ; 0 . 05 ). all results are reported as least squares means . multiple comparisons among treatments were performed using pdiff and adjusted by the tukey option for multiple comparisons of means . the significance level chosen was α = 0 . 05 . treatment effects were considered significant if p & lt ; 0 . 05 , whereas values between 0 . 05 ≦ p ≦ 0 . 10 were considered statistical trends . growth performance was not affected by cpfa as measured by adg , adfi and , f : g , and weight at harvest . feeding ractopamine affected weight at harvest , adg and adfi as well as reduction of back fat , increase in loin depth which , in turn , increased by 2 % the measure of carcass lean . cpfa did not affect color , ph , loin and chop purge , marbling score or instron force of lm samples ( see fig6 ) although ractopamine did affect redness , yellowness , lightness and instron force ( which is a measure negatively correlated with tenderness , positively correlated with chewiness ). cpfa reduced cooking loss as did ractopamine . neither cpfa nor ractopamine alone affected juiciness or off - flavor scores but in the diets combining the two a positive interaction for tenderness and chewiness was observed in which cpfa offset the negative effects of ractopamine on tenderness and chewiness . fig7 provides results related to fatty acid composition and belly fat firmness and thickness . cpfa increased sfa content , and reduced mufa content in belly fat , largely due to increased c16 : 0 and c18 : 0 and decreased c16 : 1 and c18 : 1 content in belly fat of pigs fed cpfa . the change in fatty acid profile significantly reduced the iv score when compared to the control . the content of pufa was not affected . pigs fed cpfa had firmer bellies as measured on a 1 to 3 scale , and increased edge thickness and middle thickness of the belly . interestingly , feeding cpfa as described herein did not change cpfa deposition in carcass fat ( fig8 ). based on the data , the inventors concluded that the effects of a diet supplemented with ddgs on carcass fat may be countered fully or in part by also supplementing with cpfa without compromising growth performance , carcass characteristics and / or meat quality . as expected , feeding ractopamine at 4 . 5 grams / ton had statistically significant positive effects on adg , f : g , final bw and carcass lean % ( fig5 ). however , feeding ractopamine also resulted in significant negative effects on meat quality including reductions in minolta a * and b *, an increase in instron force , increased cooking loss , reduced tenderness and increased chewiness , and a reduction in flavor score ( fig6 ). supplementing cpfa at 0 . 0375 % of the diet for 6 weeks reversed the negative effects of paylean on cooking loss , tenderness , chewiness and flavor ( fig6 ). in practice , the state of animal development will also influence the level of cpfa necessary to accomplish the objectives . further , this required level will be influenced by the species to which the method is applied and will be influenced by the objectives and costs of the other feed components . the data in the figures show that the effective rate of addition of cpfa to the diet results in harder fat , lower iv score , and improvement in meat quality ( fat hardness , meat firmness , belly thickness , cooking loss , tenderness , chewiness and flavor ) while not adversely impacting the productivity ( growth rate and feed efficiency ) of the animal . the cost of feed , when supplemented with a source of ufa such as ddgs , is reduced from the control by employing cpfa because ddgs and other feedstuffs high in ufa can be used at higher levels in the diet while still meeting the iv level and / or other meat quality measurements specified or desired by the meat processor . the source of cpfa may be , and should be , selected with an eye toward the other constituents in the source and the costs of that source . source possibilities include , but are not limited to , cotton seed , kapok seed , saba nut , and malabar chestnut , and blends thereof . the supplementation of cpfa to the animal &# 39 ; s diet may be made by blending it in the feed or by other methods of oral administration . cpfa may be used as a top dress or provided via a liquid feed system or , perhaps through the water delivery system . in short , the cpfa may be fed in any manner that encourages the animal to ingest the source of cpfa . the present invention has been described in detail . while example embodiments have been particularly shown and described with reference to steps , amounts , additions , and combinations , it will be understood by those of ordinary skill in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention .
feeding a diet supplemented with ddgs or another supplement containing ufa at a level above a threshold to animals such as swine , cattle , and poultry can have negative effects on carcass fat , certain growth parameters , and meat characteristics . however , if this diet is provided with a second supplement that contains cpfa at specified levels in the diet , the negative effects otherwise expected are wholly or at least partially countered . the invention recommends employing a supplemental source of cpfa between about 0 . 001 % and about 0 . 5 % of the diet by weight . negative effects on carcass characteristics caused by ractopamine can also be countered by the addition of this amount of at least one source of cpfa in the diet .