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Kansas Agricultural Experiment Station Research Reports

Kansas Agricultural Experiment Station contribution; no. 88-363-S; Cattlemen's Day

Articles 1 - 30 of 48

Full-Text Articles in Life Sciences

Incidence Of Pregnancy In Feedlot Heifers At Slaughter, S.B. Laudert Jan 1988

Incidence Of Pregnancy In Feedlot Heifers At Slaughter, S.B. Laudert

Kansas Agricultural Experiment Station Research Reports

Nearly 83,000 heifers were observed at slaughter during 1986 and 1987 to determine their reproductive status. Slightly less than 4 percent were found to be pregnant. Highest incidences of pregnancy were found during the winter months of November through March. Lowest incidences were found during August, September. and October.


Evaluation Of Mga And Prostaglandin As An Estrous Synchronization Procedure Under Field Conditions, P.L. Houghton, L.R. Corah, T.B. Goehring Jan 1988

Evaluation Of Mga And Prostaglandin As An Estrous Synchronization Procedure Under Field Conditions, P.L. Houghton, L.R. Corah, T.B. Goehring

Kansas Agricultural Experiment Station Research Reports

When fed MGA (0.5 mg.hd/day) for 14 days, followed by a prostaglandin injection 17 days later, a total of 736 out of 1112 heifers at 11 locations expressed signs of estrus within 5 days following the PG injection for a 66.2% response to synchronization. Response rates between locations ranged from 33 to 95% (P<.05). In a comparison of prostaglandin forms at 5 locations, using 789 heifers, response to synchronization was similar (P=.66) between Lutalyse® (62.7% response) and Bovilene® (59.6% response). First-service conception rate was compared in 411 heifers at two locations and was higher for Lutalyse (68.996) than Bovilene (59.996) (P<.08). First-service conception rate varied by technician (P<.05) and ranged from 48.7 to 83.6%.


Effect Of Hay Quality And Breed On The Onset Of Puberty And Subsequent Reproductive Performance In Beef Heifers, R.C. Perry, L.R. Corah, R.C. Cochran, J.R. Brethour Jan 1988

Effect Of Hay Quality And Breed On The Onset Of Puberty And Subsequent Reproductive Performance In Beef Heifers, R.C. Perry, L.R. Corah, R.C. Cochran, J.R. Brethour

Kansas Agricultural Experiment Station Research Reports

The effect of hay quality on the onset of puberty and subsequent reproductive performance was evaluated in 51 3/4 Hereford x 1/4 Angus (HA) heifers and 47 3/4 Hereford x 1/4 Brahman (HB) heifers. Two qualities of alfalfa hay were fed ad libitum. along with an average of 3.1 lbs/hd/day of ground sorghum grain. HB heifers were heavier and carrying more backfat and body condition (P<.05) at the start of the experiment and they maintained their weight advantage through out the experiment. A higher (P<.05) percent of the UB heifers reached puberty by 14 and 15 months of age and became pregnant during a 45 day artificial insemination breeding period. HA heifers reached puberty at a lighter (P<.05) average weight. Heifers fed high quality alfalfa hay were heavier (P<.05) by the start of the breeding season and were carrying more (P<.05) backfat and body condition. A higher percent (P=.08) of the heifers receiving higher quality hay reached puberty by 16 months of age and a higher (P=.10) percent became pregnant during the breeding period. Heifers inseminated at their pubertal estrus had lower (P=.04) first service conception rates than heifers inseminated at their second or later estruses (52% vs. 88%).


Influence Of Limited-Creep Feeding On Pre And Postweaning Performance Of Spring Born Calves, P. Houghton, F. Brazle, Gerry L. Kuhl, B. Schalles, K. Zoellner Jan 1988

Influence Of Limited-Creep Feeding On Pre And Postweaning Performance Of Spring Born Calves, P. Houghton, F. Brazle, Gerry L. Kuhl, B. Schalles, K. Zoellner

Kansas Agricultural Experiment Station Research Reports

Two limited-creep feeding trials were conducted in Northwest and Southeast Kansas using spring-born, suckling calves to evaluate the effect of available forage supply on creep-fed calf performance. Energy vs. protein creep feeds were compared at each location. Creep feed intake was limited with salt to achieve an average daily intake of about 1.5 lb per head. Calves consuming the limited energy and protein creep feeds gained from 0.1 to 0.6 lb more per head daily preweaning, and required 2.3 to 7.6 lb of creep per lb of extra weaning weight. Postweaning gains of the noncreep-fed ...


Morning Versus Evening Supplementation For Heifers Grazing Winter Range, E. Vanzant, B. Cochran, L. Corah, K. Zoellner Jan 1988

Morning Versus Evening Supplementation For Heifers Grazing Winter Range, E. Vanzant, B. Cochran, L. Corah, K. Zoellner

Kansas Agricultural Experiment Station Research Reports

Supplementing developing heifers in the morning was compared with supplementation at sundown. No difference was evident among treatments in average daily gain, distance traveled, or time spent grazing.


Influence Of Supplemental Protein Versus Energy Level On Intake, Fill, Passage, Digestibility, And Fermentation Characteristics Of Beef Steers Consuming Dormant Bluestem Range Forage, T. Delcurto, B. Cochran, T. Avery, A. Beharka Jan 1988

Influence Of Supplemental Protein Versus Energy Level On Intake, Fill, Passage, Digestibility, And Fermentation Characteristics Of Beef Steers Consuming Dormant Bluestem Range Forage, T. Delcurto, B. Cochran, T. Avery, A. Beharka

Kansas Agricultural Experiment Station Research Reports

Two trials were conducted to evaluate effects of protein versus energy level in milo/soybean meal supplements on intake and utilization of dormant, bluestem forage. Forage dry matter intake and utilization of dormant bluestem forage appears to increase at higher levels of supplemental protein. Increased supplemental energy may be associated with depressed intake and utilization, particularly when supplements are low in protein.


Stocking Rate Effects On Intensive-Early Stocked Bluestem Range, R. Cochran, E.F. Smith, Clenton E. Owensby Jan 1988

Stocking Rate Effects On Intensive-Early Stocked Bluestem Range, R. Cochran, E.F. Smith, Clenton E. Owensby

Kansas Agricultural Experiment Station Research Reports

Based on a six-year study, stocking at 2.5x and 3.0x normal season-long rates for the first half of the growing season with no grazing during the latter half results in individual steer gains that are equal to those under the 2.0x rate. The gain per acre was greatly increased at the higher stocking rates. Grass remaining in early October was 20 percent lower on pastures stocked at the 2.5x and 3.0x rates than at the 2.0x rate. However, there was no trend toward further reductions over the study period. Botanical composition did not change ...


Effect Of Medicated Mineral Mixtures And A Pinkeye Vaccine On The Gain And Health Of Steers Grazing Native Grass Pastures, F. Brazle Jan 1988

Effect Of Medicated Mineral Mixtures And A Pinkeye Vaccine On The Gain And Health Of Steers Grazing Native Grass Pastures, F. Brazle

Kansas Agricultural Experiment Station Research Reports

Feeding supplements containing an antibiotic or ionophore improved stocker gains by .06 to .26 lb per head daily. A combination of Bovatec and Aureomycin in the mineral mixture improved (P<.08) steer gains over feeding Aureomycin alone. Mineral intake was higher than expected for the steers grazing burned, double-stocked) native grass pastures in 1987. Vaccinating steers with Piliguard at turn-out had no effect on pinkeye incidence and reduced stocker gains slightly.


The Effect Of Physical Characteristics On The Price Of Stocker And Feeder Cattle, F. Brazle, J. Mintert, Ted C. Schroeder, O. Grunewald Jan 1988

The Effect Of Physical Characteristics On The Price Of Stocker And Feeder Cattle, F. Brazle, J. Mintert, Ted C. Schroeder, O. Grunewald

Kansas Agricultural Experiment Station Research Reports

A survey of feeder cattle sales was conducted at seven Kansas cattle auctions during 1986 and 1987. A wide variety of physical characteristics was found to influence feeder cattle prices. The price impact resulting from changes in fill and condition varied seasonally. Although calves showing any signs of health problems received severe price discounts, the presence of other undesirable characteristics also resulted in discounts, but to lesser degrees.


Farm, Wholesale, And Retail Beef Price Relationship, Ted C. Schroeder Jan 1988

Farm, Wholesale, And Retail Beef Price Relationship, Ted C. Schroeder

Kansas Agricultural Experiment Station Research Reports

Analysis of weekly retail, wholesale, and farm beef price data indicated that a time lag exists between price changes at the various market levels. Farm-level slaughter cattle price changes typically lead wholesale beef price changes by 2 to 3 weeks. Similarly, wholesale beef price changes typically lead price changes at the retail level by 3 to 4 weeks.


Effect Of Limit-Fed, High Energy Growing Rations On The Performance Of Feedlot Steers, G. Goldy, B. Downey, K. Bolsen, Jack G. Riley Jan 1988

Effect Of Limit-Fed, High Energy Growing Rations On The Performance Of Feedlot Steers, G. Goldy, B. Downey, K. Bolsen, Jack G. Riley

Kansas Agricultural Experiment Station Research Reports

Steers red high-concentrate limit-fed rations were more efficient during growing than steers fed silage plus grain at 25% of their dry matter (DM) intake, or silage only. The limit-fed cattle also tended to gain faster (P<.10) and were more efficient (P<.05) during the finishing phase and did not have the expected depressed DM intakes compared to cattle fed the other growing-phase rations. Steers fed barely had lower DM intakes (P<.05) but gained more efficiently (P<.05) than those fed grain sorghum.


Daily Or Weekly Rotational Feeding Of Bovatec®- And Rumensin®/Tylan® To Cattle On A Steam-Flaked Corn Finishing Ration, Robert T. Brandt Jr. Jan 1988

Daily Or Weekly Rotational Feeding Of Bovatec®- And Rumensin®/Tylan® To Cattle On A Steam-Flaked Corn Finishing Ration, Robert T. Brandt Jr.

Kansas Agricultural Experiment Station Research Reports

One hundred sixty-five crossbred steers averaging 823 lb were utilized to evaluate the daily or weekly rotational feeding of ionophores. Treatments were (g/ton of feed, 90% dry basis): 1) Bovatec (B; 30), 2) Rumensin plus Tylan (RT; 25 and 10, respectively), 3) treatments one and two in a daily rotation (D), and 4) treatments one and two in a weekly rotation (W). Steers fed RT consumed less (P<.05) dry matter than B, D>or W steers. No differences (P>.15) in daily gain were observed, suggesting that the increased consumption by B, D) and W steers was accompanied by an al teration in passage ...


Effect Of Tetronasin On Frothy Bloat In Cattle Caused By High-Grain Diet, L.R. Neibarger, Tiruvoor G. Nagaraja Jan 1988

Effect Of Tetronasin On Frothy Bloat In Cattle Caused By High-Grain Diet, L.R. Neibarger, Tiruvoor G. Nagaraja

Kansas Agricultural Experiment Station Research Reports

Feeding Tetronasin reduced incidence of frothy bloat in cattle fed a high-grain diet. The effective dose was 0.25 mg/kg body weight when administered prior to the onset of frothy bloat. At 0.15 mg/kg body weight, the antibiotic was less effective but the degree of bloat was considerably less than that of steers fed no antibiotic. Tetronasin also reduced the severity of bloat in steers that were already bloating prior to its administration.


Experimental Induction And Monitoring Of Liver Abscesses In Cattle With Ultrasonography, K.F. Lechtenberg, T.B. Avery, Tiruvoor G. Nagaraja Jan 1988

Experimental Induction And Monitoring Of Liver Abscesses In Cattle With Ultrasonography, K.F. Lechtenberg, T.B. Avery, Tiruvoor G. Nagaraja

Kansas Agricultural Experiment Station Research Reports

We have demonstrated that ultrasonography can be used to visualize liver abscess in live cattle. We have also developed a nonsurgical method of catheterizing the bovine portal vein and experimentally inducing liver abscesses by inoculating the portal vein with Fusobacterium necrophorum bacteria.


Evaluating The Availability Of Nutrients For Maintenance And Growth In Ruminants, K. Gross, D. Harmon, T. Avery Jan 1988

Evaluating The Availability Of Nutrients For Maintenance And Growth In Ruminants, K. Gross, D. Harmon, T. Avery

Kansas Agricultural Experiment Station Research Reports

Two experiments were performed with mature wether lambs to evaluate availability of selected nutrients and volatile fatty acids for maintenance and growth. We used a technique in which known amounts of volatile fatty acids were infused into the rumen and casein into the abomasum. Sampling portal blood allowed measurement of nutrients absorbed across the gastrointestinal tract. Approximately 49, 62, and 21% of the infused acetate, propionate, and butyrate, respectively, were absorbed across the gastrointestinal tract.


Testing Feedstuffs Using Near-Infrared Reflectance Spectroscopy (Nirs), P.C. Dubois, L.H. Harbers Jan 1988

Testing Feedstuffs Using Near-Infrared Reflectance Spectroscopy (Nirs), P.C. Dubois, L.H. Harbers

Kansas Agricultural Experiment Station Research Reports

Over 16 years ago, an analytical instrument was developed that could rapidly determine the concentration of organic compounds from the spectra produced by the bonding between certain molecules. The instrument is based on the principle that those molecules absorb electromagnetic radiation in the infrared region. Compounds may be quantitated by using a computer to compare absorption bands in the near-infrared spectrum to those from a large calibration set of known composition. Peaks from compounds such as water, protein, fat, and carbohydrate may be translated into nutrient components such as moisture, crude protein, crude fat, acid detergent fiber, etc. all this ...


Effect Of Environmental Temperature And Inoculants On The Fermentation Of Alfalfa And Forage Sorghum Silages, K. Bolsen, A. Laytimi, L. Nuzback, R. Hart Jan 1988

Effect Of Environmental Temperature And Inoculants On The Fermentation Of Alfalfa And Forage Sorghum Silages, K. Bolsen, A. Laytimi, L. Nuzback, R. Hart

Kansas Agricultural Experiment Station Research Reports

The inoculants, TriLac ®and Ecosyl® increased the rate and efficiency of the ensiling process in both high (50%) and low (32.5%) dry matter alfalfa, regardless of temperature. In both alfalfa trials, the inoculated silages had significantly lower pH, acetic acid, ethanol, and ammonia-nitrogen values and higher lactic acid values than their control counterparts. The inoculants worked equally well when fermentation was at 60 or 90 F. Although similar effects were obtained with forage sorghum, the differences were not as pronounced as those for the alfalfa silages.


Relationship Between Agronomic And Silage Quality Traits Of Forage Sorghum Cultivars, J. White, K. Bolsen, B. Kirch Jan 1988

Relationship Between Agronomic And Silage Quality Traits Of Forage Sorghum Cultivars, J. White, K. Bolsen, B. Kirch

Kansas Agricultural Experiment Station Research Reports

Results from two trials evaluating 11 forage sorghums as silage crops indicated that silage quality traits of voluntary intake, digestibility, and crude protein content were linearly associated with the agronomic characteristics of days to half bloom and plant height. Intake was negatively associated with plant height (r = -.49); digestibility was negatively associated with days to half bloom (r = -.39) and plant height (r = -.49); and crude protein was negatively associated with days to half bloom (r = - .51) and plant height (r = -. 71). Within the same cultivar, but between years, voluntary intake varied by as much as 30 percent, digestibility by ...


Yield, Chemical Composition, And Feeding Value Of Winter Cereal Silages And Hays: A 3 Year Study, S. Azimi, K. Bolsen, A. Laytimi, S.H.M. Esmail, J. Hoover, Q.K. Ye Jan 1988

Yield, Chemical Composition, And Feeding Value Of Winter Cereal Silages And Hays: A 3 Year Study, S. Azimi, K. Bolsen, A. Laytimi, S.H.M. Esmail, J. Hoover, Q.K. Ye

Kansas Agricultural Experiment Station Research Reports

Three trials were conducted to compare silage and hay yields and feeding values of winter cereal foraged harvested in the boot and dough stages of maturity. Included were triticale; common rye; Kanby barley; and Centurk, Arkan, and Bounty 205 wheats. As expected, forage dry matter (DM) yields were higher at the dough stage then boot stage, and silage yields tended to be higher than those for hay. In Trials 2 and 3 (1986-87), barley and rye forage yields were lower than wheat yields. In all three years, wet weather conditions made hay-making difficult. In Trial 1, cattle performance from dough ...


Comparison Of Feedlot Performance Of Steer Calves Produced By Angus X Hereford And Brahman X Hereford Cows, J.R. Brethour, D. Patterson, K. Olson, L. Corah Jan 1988

Comparison Of Feedlot Performance Of Steer Calves Produced By Angus X Hereford And Brahman X Hereford Cows, J.R. Brethour, D. Patterson, K. Olson, L. Corah

Kansas Agricultural Experiment Station Research Reports

Steer calves that were 75 percent Hereford and either 25 percent Angus (BWF) or Brahman (BRX) were compared in a feedlot study that involved either high-concentrate or high-silage finishing rations. The BRX steers gained significantly faster, but there was no concomitant response in feed efficiency. The ration energy utilization by BRX steers appeared to be less than that of BWF steers. Performance of both breeds was poorer on the high-silage ration than on the high-grain ration, and there was no breed by ration interaction. A greater proportion of BWF calves graded USDA choice, but there was little difference between breeds ...


Effect Of Limited - Creep Feeding On Performance Of Spring-Born Calves, D. Simms, Gerry L. Kuhl Jan 1988

Effect Of Limited - Creep Feeding On Performance Of Spring-Born Calves, D. Simms, Gerry L. Kuhl

Kansas Agricultural Experiment Station Research Reports

Three limited-creep feeding trials were conducted with spring-born suckling calves on native grass. The 1696 crude protein, high energy creep feed containing Bovatec® was fed from mid-August to weaning in mid-October. Limited-creep feeding increased (P<.05) calf gains .19 lb per/head/daily with an average daily consumption of 2.15 lb, giving a creep feed-to-gain conversion rate of 11.2.


Influence Of Supplemental Grain Type On Forage Utilization By Beef Steers Consuming Early Summer Bluestem, E.S. Vanzant, R.C. Cochran, A.A. Beharka, T.B. Avery Jan 1988

Influence Of Supplemental Grain Type On Forage Utilization By Beef Steers Consuming Early Summer Bluestem, E.S. Vanzant, R.C. Cochran, A.A. Beharka, T.B. Avery

Kansas Agricultural Experiment Station Research Reports

Supplementation of early summer bluestem with low levels of corn, wheat, or sorghum grain had no effect on forage intake, forage digestibility, or total dry matter digestibility in beef steers, compared with a regimen of no supplementation. Increased total dry matter intakes for the supplemented steers reflected supplement consumption.


Influence Of Sustained Rumensin Release On Steer Performance And Forage Utilization, B. Cochran, E. Vanzant, T. Avery, Jack G. Riley Jan 1988

Influence Of Sustained Rumensin Release On Steer Performance And Forage Utilization, B. Cochran, E. Vanzant, T. Avery, Jack G. Riley

Kansas Agricultural Experiment Station Research Reports

Steers managed within an intensive-early stocking program and receiving Rumensin® via a slow-release bolus tended to have higher average daily gains than steers not receiving Rumensin. However, forage organic matter intake, fill, digestibility, and diet selection showed little response to Rumensin administration.


Performance Of Stocker Heifers And Steers Grazing High Endophyte Fescue And Offered Oxytetracycline In A Mineral Mixture., K. Coffey, F. Brazle Jan 1988

Performance Of Stocker Heifers And Steers Grazing High Endophyte Fescue And Offered Oxytetracycline In A Mineral Mixture., K. Coffey, F. Brazle

Kansas Agricultural Experiment Station Research Reports

Two experiments were conducted to evaluate the performance of stocker calves grazing high-endophyte fescue (68 to 70%) and offered oxytetracycline in a free-choice mineral supplement. In Experiment 1, 24 yearling crossbred heifers were utilized in a 112-day grazing study beginning on June 18. Performance of both control calves and those receiving oxytetracycline was extremely poor, making data interpretation difficult. Average oxytetracycline consumption was 327 mg per head, daily. Approximately 8296 of the total grazing time occurred during the daylight hours (6arn - l0pm) for both treatment groups. Heifers offered the medicated mineral mix grazed 20 minutes more than heifers offered the ...


Effect Of Ralgro® On Performance Of Steers Grazing High And Low Endophyte Fungus-Infested Tall Fescue Pastures, F.K. Brazle Jan 1988

Effect Of Ralgro® On Performance Of Steers Grazing High And Low Endophyte Fungus-Infested Tall Fescue Pastures, F.K. Brazle

Kansas Agricultural Experiment Station Research Reports

Steers were either not implanted or implanted with 36 or 72 mg of Ralgro, then allowed to graze on both high and low endophyte fungus tall fescue pastures. Ralgro had a greater effect on improving gains of steers grazing high endophyte fungus pastures than on those grazing lowly infected fescue pastures.


Effect Of Depo-Mga On The Prevention Of Pregnancy In Grazing Heifers, L.R. Corah, F.K. Brazle, G.W. Boyd, T. Goehring Jan 1988

Effect Of Depo-Mga On The Prevention Of Pregnancy In Grazing Heifers, L.R. Corah, F.K. Brazle, G.W. Boyd, T. Goehring

Kansas Agricultural Experiment Station Research Reports

Two field trials were conducted to evaluate various dosage levels of Depo-MGA® for preventing pregnancy in grazing heifers. Injecting Depo-formulated MGA subcutaneously in the ear at dosages of 60, 90 or 120 mg effectively prevented pregnancy for up to 135 days. There was no effect on average daily gain.


Effects Of Sugar, Internal Cooking Temperature, And Hot-Boning On The Characteristics Of Low Fat, Restructured, Value-Added Beef Roasts, S.J. Goll, Melvin C. Hunt, Donald H. Kropf, Curtis L. Kastner Jan 1988

Effects Of Sugar, Internal Cooking Temperature, And Hot-Boning On The Characteristics Of Low Fat, Restructured, Value-Added Beef Roasts, S.J. Goll, Melvin C. Hunt, Donald H. Kropf, Curtis L. Kastner

Kansas Agricultural Experiment Station Research Reports

Low fat, restructured beef roasts were made from muscles that were conventionally or hot-boned. Differing combinations of salt, phosphate, and glucose were added. Then roasts were cooked to 145 ÌŠF or 200 ÌŠF. Roasts from conventionally boned muscle generally had less warmed-over flavor and higher acceptability scores than those from hot-boned muscle. Adding glucose with salt and phosphate helped suppress warmed-over flavor throughout display and did not reduce flavor acceptability or increase cooking loss. Roasts cooked to 200 ÌŠF had lower warmed-over flavor scores and were more acceptable, but were less cohesive and had higher cooking losses than roasts cooked ...


Kansas Custom Cattle Feeding Practices, Ted C. Schroeder, Gerry L. Kuhl Jan 1988

Kansas Custom Cattle Feeding Practices, Ted C. Schroeder, Gerry L. Kuhl

Kansas Agricultural Experiment Station Research Reports

A survey of Kansas custom cattle feedlots was conducted in the fall of 1987. This paper summarizes the survey and discusses some of the custom cattle feeding services and charges being offered.


Effect Of Cobactin On The Feedlot Performance And Carcass Traits Of Beef Steers, L. Corah, Ronald V. Pope Jan 1988

Effect Of Cobactin On The Feedlot Performance And Carcass Traits Of Beef Steers, L. Corah, Ronald V. Pope

Kansas Agricultural Experiment Station Research Reports

The addition of Cobactin to feedlot rations had no significant effect on average daily gain or feed efficiency, but did improve quality grade of steers fed for 110 days.


Effect Of Fat Source On Performance And Carcass Quality Of Finishing Steers, Robert T. Brandt Jr. Jan 1988

Effect Of Fat Source On Performance And Carcass Quality Of Finishing Steers, Robert T. Brandt Jr.

Kansas Agricultural Experiment Station Research Reports

Two trials that utilized 356 steers were conducted to evaluate the effects of various fat sources (3.596 of ration dry matter) on performance and carcass traits of finishing cattle fed flaked milo diets. In trial 1, soybean oil, bleachable tallow, and yellow grease (blend of tallow and restaurant grease) were compared to a nonfat control. Feeding fat increased (P<.05) daily gain, feed efficiency, carcass weight, and dressing percent of steers. Soybean oil and yellow grease also tended to increase 12th rib backfat thickness and marbling. Feed costs of gain were improved only by yellow grease. However, when increased carcass yield and quality were considered, there was a significant economic return from all fat sources. In trial 2, fat treatments were acidulated soybean soapstock (SBSS), tallow, a blend of 7096 SBSS:3096 tallow, and yellow grease. Feeding tallow or the SBSS: tallow blend improved (P<.05) feed efficiency by 7.796 compared to the nonfat control. Pooled across source, feeding fat increased (P<.10) backfat thickness and marbling. Compared to the control, feed cost of gain was reduced 6 cents/l b by the SBSS:tallow blend. However, when increased carcass value was accounted for, net returns of $3.50 to $6.00 per head were seen for SBSS, tallow, and SBSS:tallow priced at 13, 17, and 13 cents per lb, respectively. The SBSS:tallow blend provided greater performance than was predicted by observed performance of steers fed SBSS or tallow separately, an indication of associative response. In trial 2, intake and gain were lowest for yellow grease, resulting in a negative economic return, which is in complete disagreement with results obtained in trial 1.