Influence of free fatty acid content on the feeding value of yellow grease in finishing diets for feedlot cattle

Roughage level and supplemental fat for newly received finishing calves: effects on growth performance, health, and physiological responses

This experiment evaluated the effects of roughage levels and supplemental fat on intake, growth performance, health, and physiological responses of newly received finishing cattle during 58-d receiving period. A total of 72 crossbred steers (initial body weight [BW] = 200 ± 13 kg) were used in a randomized complete block design with a 2 × 2 factorial arrangement of treatments, consisting of two roughage levels (wheat hay at 30% [R30] or 60% [R60]; dry matter [DM] basis) and two levels of supplemental fat (yellow grease at 0% [-FAT; no additional fat] or 3.5% [+FAT]; DM basis). Upon arrival, calves were individually weighed, blocked by off-truck shrunk BW, and assigned to 24 soil-surfaced pens (three calves per pen). Shrunk BW was also collected on day 58 for the calculation of average daily gain (ADG). Throughout the study, calves were assessed for bovine respiratory disease (BRD). Effects of roughage level × supplemental fat interaction were only observed for diet particle size distribution and estimated physically effective neutral detergent fiber (peNDF) of diets (P ≤ 0.10). Adding fat to R60 diets tended to increase the percentage of particles retained in the 8-mm screen (P = 0.06) and the estimated peNDF (P = 0.10), but did not affect R30 diets. Dietary roughage level did not affect DM intake (DMI; P = 0.85). Calves-fed R30 tended to have greater ADG and final BW than calves-fed R60 (P ≤ 0.08). Gain efficiency (gain:feed ratio; G:F) was greater for calves-fed R30 than calves-fed R60 (P = 0.01). Dietary roughage level did not affect morbidity and mortality (P ≥ 0.11). Supplemental fat did not affect DMI (P = 0.6) but tended (P = 0.09) to increase ADG compared to -FAT diets. The G:F was greater for calves-fed +FAT than -FAT (P = 0.03). The +FAT diet tended (P = 0.10) to increase the number of retreatments against BRD compared to -FAT, although the total number of antimicrobial treatments required to treat sick calves (P = 0.78) and the mortality rate (P = 0.99) were not affected by supplemental fat. Feeding +FAT diet tended (P ≤ 0.09) to increase plasma concentration of cortisol and immunoglobulin-G compared to -FAT. In summary, feeding 30% roughage diets or adding 3.5% yellow grease (DM basis) as supplemental fat increased G:F during the feedlot receiving period.

Effects of including Sweet Bran or modified distillers grains in the diet of feedlot steers and sorting at terminal implant on growth performance, feeding behavior, and liver abscess occurrence

The objectives were to assess the effects of dietary Sweet Bran (Cargill Corn Milling, Blair, NE) on performance and feeding behavior of feedlot steers and determine if terminal implant pen sorting affects performance, feeding behavior, and liver abscess (LA) rate. Two hundred sixteen Angus-cross steers (253 ± 18 kg) were stratified by body weight (BW) to 36 pens. From d 0 to 60, diets contained 40% Sweet Bran (SWBR) or 25% modified distiller’s grains and 15% dry rolled corn (MOD; n = 18 pens/treatment). On d 60, steers began transition within treatments to finishing diets containing 25% Sweet Bran or 25% modified distiller’s grains (MDGS). On d 111, half of the pens for each dietary treatment were re-stratified by BW to pens (SORT) while the other half were returned to original pens (NOSORT; n = 9 pens/treatment). Steer BW and pen dry matter intake (DMI) were recorded monthly. Rate of feed disappearance was determined on d 5/6, 53/54, 104/105, and 117/118. Pen was the experimental unit for all analyses. The model included the fixed effect of diet for all pre-sort analyses; post-sort analyses included the fixed effects of diet, sort, and the interaction and the random effects of pen and the interaction of diet and pen. On d 60, SWBR had greater BW than MOD (P = 0.05), and SWBR had a greater average daily gain (ADG) from d 0 to 60 (P = 0.05). Though there were no differences after d 28, SWBR had greater DMI d 0 to 28 (P = 0.05). From d 60 to 88, SWBR tended to have lesser ADG than MOD (P = 0.09). Post-sort (d 111 to 196), SWBR tended to have lesser ADG than MOD (P = 0.06), and SORT had a greater rate of feed disappearance than NOSORT (d 117/118; P = 0.01); there were no differences on other dates (Diet: P ≥ 0.38). For final BW, there was a tendency for MOD to be greater than SWBR, and SORT tended to be greater than NOSORT (Diet: P = 0.06; Sort: P = 0.10). Pre- and post-sort ruminal pH had no treatment by day differences (P ≥ 0.77). LA incidence averaged 25%, though rate was not affected by diet, sorting, or the interaction (P ≥ 0.16). Overall, there were no dietary differences in feed disappearance rates, though SORT steers had greater rate of feed disappearance than NOSORT steers on d 117/118. Nominal differences in feeding behavior were noted and including Sweet Bran in the diet was beneficial in the growing period as cattle adjusted to the feedlot.

Meal nutritional characteristics and oil profile of sprouted, dehulled, and solvent-extracted canola

BACKGROUND

Canola meal has limited utilization in feed and food applications because of the presence of antinutritional factors and a high fiber content. Thus, the present study used 3-day canola seed sprouting followed by hull removal to improve the nutritional quality of canola as a feed and food ingredient to further enhance and diversify the canola market.

RESULTS

Seed sprouting and the hull removal process resulted in 63.2% sprouts, 29.3% mix fractions (MF) (hulls, ungerminated seed, and delayed sprouts) and 8.1% mass loss during sprouting. Fresh sprouts and MF were dried, ground and defatted to compare the obtained meals and oils with their counterparts of raw seed. Defatted sprouts (DFSP) resulted in a 46.2% reduction in crude fiber, a 34.3% reduction in acid detergent fiber and a 43.4% reduction in neutral detergent fiber compared to defatted raw seed (DFSE). DFSP provided a 10.1% higher protein content and a 5.9% increase in total amino acid content with higher essential amino acids compared to DFSE. Total carbohydrate was lowered by 5.5%, phytic acid content was lowered by 25.9%, and ash content was lowered by 5.5% in DFSP, whereas total glucosinolate content was higher in DFSP (13.1 μmol g^-1 ) than in DFSE (8.8 μmol g^-1 ). Sprouts and MF showed an oil content of 38.4% and 9.6%, respectively, compared to raw seed (34.5%).

CONCLUSION

Sprouting and hull removal of canola seed can potentially provide nutritive meal for food and feed applications. © 2022 Society of Chemical Industry.

Feeding Value of Supplemental Fat as a Partial Replacement for Steam-Flaked Corn in Diets for Holstein Calves during the Early Growing Phase

In calf-fed Holstein steers, the early growing phase is characterized by very high relative dry matter intake accompanied with lower-than-expected efficiency of energy utilization. Although fat is commonly supplemented in growing finishing diets, the comparative feeding value has not been investigated during the initial receiving-growing period. Eighty-four Holstein calves (127.7 ± 2.1 kg body weight) were used to evaluate the effects of including 3.5% of supplemental yellow grease (YG) in the diet on characteristics of growth-performance and dietary energy utilization of calves during the early growth phase. Morbidity and mortality were not affected by dietary treatments. Yellow grease supplementation did not affect DMI, but tended to increase ADG (4.6%; p = 0.07) and increased (p ≤0.03) gain efficiency (5.8%) and dietary net energy for maintenance (NEm) and gain (NEg) by 4.1 and 5.3%, respectively. Based on performance data, the estimated N.E. value of supplemental YG was 4.67 and 3.68 Mcal/kg for NEm and NEg, respectively. These values are consistent with current tabular values assigned for vegetable oils (4.75 and 3.51 Mcal/ kg), but markedly less (16.6%) than NEm value assigned for yellow grease (5.60 Mcal NEm/kg; NASEM, 2016).

Influence of unsaturated to saturated ratio of fatty acids reaching the duodenum on postruminal digestion of stearic acid in Holstein steers fed a high-fat finishing diet

OBJECTIVE

To evaluate the influence of the unsaturated to saturated ratio of fatty acids (FAs) reaching the duodenum on postruminal digestion of FAs, mainly focused on stearic acid (C18:0).

MATERIALS AND METHODS

Six Holstein steers [208 ± 3 kg initial live weight (LW)] with cannulas in the abomasum and proximal duodenum were used in a replicated 3 × 3 Latin square design. Steers were fed a fixed amount of a basal steam-flaked corn-based diet containing 8% supplemental fat and were daily infused via abomasum with 0, 67, and 165 gm oleic acid (C18:1). The experiment lasted for 42 days.

RESULTS

The daily total FA (TFA) intake (dietary FA intake plus abomasal infusion of oleic acid) represented a 1.78, 2.10, and 2.56 gm TFA/kg LW ratio. The unsaturated to saturated ratio of FAs entering the duodenum increased (p < 0.01) as level C18:1 infusion into the abomasum increased. Infusion of C18:1 tended (quadratic component, p = 0.07) to improve postruminal TFA digestion, being maximal for the 67 gm/day infusions. This increase in TFA digestion was due to increased (quadratic component, p = 0.03) postruminal C18:0 digestion (postruminal digestion of the other FAs was not different, p ≥ 0.13).

CONCLUSION

Increasing the unsaturated to saturated ratio of FAs entering the small intestine will enhance intestinal C18:0 digestion. This positive effect is expected to be more likely beneficial when FA intake is high (and thus, the duodenal flow of FA is high), but this benefit looks diminished when the quantity of TFA reaching the intestine exceeds the proportion of 2.13 gm FA/kg LW.

Grease trap waste (griddle grease) as a feed ingredient for finishing lambs: growth performance, dietary energetics, and carcass characteristics

Forty-eight (37.7 ± 3.4 kg, initial shrunk live weight) lambs were used in a 61 d experiment to evaluate the energy value of grease trap waste (GT) at four levels of supplementation (0%, 2%, 4%, and 6%). Supplemental GT replaced cracked corn in the basal diet. The GT contained 6.4% moisture, 3.1% impurities, and 79.8% total fatty acids (FA). Increasing GT level in diets did not affect dry matter intake and daily weight gain but linearly increased gain efficiency and estimated dietary net energy (NE). However, the ratio of observed-to-expected diet NE decreased with increased levels of GT. The estimated NE values for GT based on FA intake were in close agreement (98% and 102% of predicted, respectively) with those NE values determined by replacement technique for 2% and 4% supplementation level. However, the observed NE value for GT supplemented at the 6% level was 9% lower than predicted. Kidney–pelvic–heart fat increased as level of GT supplementation increased; otherwise, carcass characteristics and shoulder composition were not affected. We conclude that GT is a suitable alternative to conventional feed fats in diets for finishing lambs. The estimated NE of GT is 93% the energy value assigned by current standards for tallow and yellow grease.

Effects of supplemental fat concentration on feeding logistics, animal performance, and nutrient losses of heifers fed finishing diets based on steam-flaked corn and sorghum-based distiller's grains

The use of distiller's grains (DG) in beef cattle finishing diets is a common practice. However, the effects of supplemental fat on performance and nutrient losses of cattle fed diets containing DG are not known. Therefore, we fed 398 crossbred yearling heifers (initial BW = 373.5 kg) for 106 d to determine the effects of dietary fat concentration and sorghum-based wet distiller's grains with solubles (SWDGS) on performance, carcass characteristics, and nutrient losses of finishing cattle. Treatments included two 92% concentrate, steam-flaked corn (SFC)-based diets with 0% or 3% added fat from yellow grease and 3 SFC-based diets with 15% SWDGS (DM basis) that contained either 0%, 1.5%, or 3% added fat (8 pens per treatment) in a randomized block design. Overall DMI and ADG were 5% to 6% greater (P < 0.01) for heifers fed 15% SWDGS than for those fed 0% SWDGS. Among heifers fed 15% SWDGS, DMI was greatest (P = 0.04; quadratic effect) and ADG tended (P = 0.12; quadratic effect) to be greatest for heifers fed 1.5% fat. The ADG:DMI did not differ between 0% SWDGS with 0% or 3% fat, and was not altered by replacing a portion of SFC with SWDGS (P > 0.36). However, ADG:DMI tended to increase as more fat was added to diets with 15% SWDGS (P = 0.06). Average hot carcass weight (HCW) was 5 kg greater (P = 0.05) when SWDGS was fed, but HCW tended to be greatest for heifers fed 15% SWDGS with 1.5% fat (P = 0.09, quadratic effect). Heifers fed 0% SWDGS with 0% fat tended to have a lower marbling score, less rib fat, lower average yield grade (P < 0.08), and more (P < 0.01) yield grade 1 carcasses than heifers fed 0% SWDGS with 3% fat. Averaged across fat levels, heifers fed 15% SWDGS had more rib fat and a higher yield grade (P < 0.03) than heifers fed 0% SWDGS. Feeding 15% SWDGS did not alter carcass quality grade distribution compared to feeding 0% SWDGS, but 15% SWDGS produced fewer yield grade 3 carcasses (P = 0.03) than 0% SWDGS. The calculated NEg of SWDGS (1.36 Mcal/kg) was 91% of the tabular value for dry rolled corn (1.50 Mcal/kg) and 84% of the tabular value for SFC (1.62 Mcal/kg). Nitrogen intake, and N excretion were greater (P < 0.05) in heifers fed 15% SWDGS than in heifers fed the 0% SWDGS diets, but N loss as a % of N intake was less (P < 0.05). Our results suggest adding 1.5% fat to diets containing 15% SWDGS may improve beef cattle performance; however, feeding logistics need to be considered when pricing wet DG.

Quality effects on beef strip steaks from cattle fed high-protein corn distillers grains and other ethanol by-products

The objective of this study was to evaluate the effects of feeding high-protein corn distillers grains on fresh beef quality. Steers (n = 60) were fed one of five diets for 190 d (six pens with 10 cattle/pen/diet): a corn control (Control), 40% high-protein dry distillers grains plus solubles (HP-DDGS), 40% dry distillers grains plus solubles (DDGS), 40% wet distillers grains plus solubles (WDGS), or 40% bran plus solubles (Bran). Eighteen Choice carcasses (three cattle per pen) were randomly selected within each treatment; however, two carcasses were lost during carcass selection. Strip loins (Longissimus lumborum, IMPS # 180) were collected, divided into three equal portions, and aged for 2, 9, or 23 d. Steaks were fabricated following each aging period and placed under retail display (RD) conditions for 0, 4, or 7 d. Pen was the experimental unit. Hot carcass weight at harvest was 391 kg (SD 31.6 kg). Dietary treatment had no effect on tenderness (Warner-Bratzler shear force) within each aging period (P > 0.05). After 7 d of RD, following all aging periods, steaks from cattle fed HP-DDGS had the greatest visual discoloration except for DDGS and Bran after 23 d (P < 0.05). The steaks from cattle fed HP-DDGS had lower (P < 0.05) redness (a*) values than all other treatments following 7 d of RD. Lipid oxidation increased (P < 0.001) during RD at all aging periods, as measured via thiobarbituric acid reactive substance (TBARS). A day of RD-by-dietary treatment effect (P < 0.001) was observed for lipid oxidation. After 7 d of RD, steaks from cattle fed HP-DDGS had higher TBARS than all other treatments except WDGS (P < 0.01). A trend was found for sarcomere length (P = 0.07), with steaks from cattle fed Bran having the longest sarcomere length compared with all other treatments. An aging effect was found for free calcium content (P < 0.001) where steaks aged 9 and 23 d had significantly higher levels of free calcium than those aged 2 d. There was a tendency (P = 0.07) that steaks from cattle fed WDGS contained more free calcium than steaks from cattle fed DDGS or Bran. Although there were no statistical differences, there was a trend (P = 0.07) that steaks from cattle fed HP-DDGS had higher levels of PUFAs and C18:2. These results suggest that feeding high protein distillers grains has no detriment on tenderness, but may alter the lipid profile of the muscle, resulting in decreased color stability, increased lipid oxidation, and decreased shelf life.

Comparative effects of ‘solid’-fat sources as a substitute for yellow grease on digestion of diets for feedlot cattle

Five cannulated Holstein steers fed a steam-flaked corn-based growing diet containing 40% of alfalfa hay were used in a 5 × 5 Latin square design to examine the effect of ‘solid’ supplemental fats as a substitute for yellow grease (YG) on the extent and site of digestion. Treatments were (% of diet DM) as follows: (1) no supplemental fat; (2) 5% YG; (3) 5.88% calcium soaps (ML); (4) 5% flaked palmitic acid (RP10); and (5) 5% hydrogenated palm fatty acid distillate (HPFAD). Supplemental fats replaced the corn in the control diet. Supplemental fat decreased (P &lt; 0.01) ruminal and total-tract digestion of organic matter and tended to decrease (P = 0.06) ruminal digestion of neutral detergent fibre, with no effects on ruminal digestion of feed N, microbial N efficiency, or total-tract digestion of N and neutral detergent fibre. With the exception of RP10, fat supplementation decreased (P &lt; 0.03) postruminal digestion of C18:0. Compared with the original C16:0:C18:0 ratio of solid fats, the C16:0:C18:0 ratio of fatty acids (FAs) entering the small intestine markedly decreased for all solid-fat treatments. Ruminal biohydrogenation of YG and ML were 73% and 49% respectively. On the basis of FA intake, postruminal FA digestion of YG, ML, RP10 and HPFAD was 0.97, 0.94, 0.92 and 0.80 of expected respectively. This experiment confirmed that postruminal digestion of total FAs of conventional supplemental yellow grease is a predictable function of total FA intake per unit of bodyweight. However, in the case sources of the solids fats, this relationship (FA intake and postruminal digestion of FAs) was less consistent. This may be due to their physical and chemical nature (saturatedFA:unsaturated FA ratio). On the basis of the nutrient digestion and postruminal FA digestibility observed in the present experiment, solid supplemental fats do not afford appreciable advantages over conventional YG when supplemented in growing diets (forage level ~400 g/kg diet DM) for feedlot steers.

Impact of feeding de-oiled wet distillers grains plus solubles on beef shelf life

Research was conducted to determine the effect of feeding de-oiled wet distillers grains plus solubles (WDGS) on beef fatty acid profile, retail shelf life and development of oxidation products during retail display (RD). A total of 336 crossbred yearling steers (initial BW = 351.08 ± 19.05 kg) were fed 1 of 7 dietary treatments: an all corn control (1:1 blend of dry rolled and high moisture corn), 35%, 50%, or 65% inclusion of WDGS, either full-fat or de-oiled. Within each treatment 15 Choice carcasses were randomly selected ( = 105), strip loins were obtained, aged 7 and 21 d, and representative steaks from each strip loin were placed in RD conditions for 7 d. Fatty acid profiles were determined (mg/100 g tissue basis) and differences ( ≤ 0.05) were found in the C16:1, C18:1T, C18:2 and total polyunsaturated fatty acids (PUFA) among dietary treatments. Palmitoleic acid (C16:1) was predominant ( < 0.0001) in the corn control group, intermediate in the 35% de-oiled WDGS group, but no differences ( > 0.05) were observed between all other diets. Elaidic acid (C18:1T) was greater ( = 0.01) in the 65% full-fat WDGS group, least for the corn control group, and intermediate for all other diets. Linoleic acid (C18:2) was greater ( = 0.0001) in all 3 full-fat WDGS groups and 65% de-oiled WDGS group (290.98 mg/100 g, on average), intermediate in the 50% and 35% de-oiled WDGS groups (231.08 and 227.16 mg/100 g, respectively) and least for the corn control group (177.70 mg/100 g). The PUFA content was greater ( < 0.01) in all 3 full-fat WDGS groups and 65% de-oiled WDGS group (337.13 mg/100 g, on average), intermediate in the 50% and 35% de-oiled WGDS groups (274.77 and 273.84 mg/100 g, respectively) and least for the corn control group (223.98 mg/100 g). Dietary treatment did not alter discoloration ( = 0.30) or lipid oxidation ( = 0.36). Shear force decreased with age and RD ( < 0.0001) but dietary treatment had no effect on shear force ( = 0.93). In general, feeding 35% and 50% de-oiled WDGS had intermediate PUFA content relative to a corn control or full-fat WDGS diet. Feeding de-oiled WDGS did not seem to increase beef shelf life and does not negatively alter beef quality parameters in relation to full-fat WDGS.

Feeding value of supplemental curcas crude oil in finishing diets for feedlot lambs

The objective of this experiment was to determine the feeding value of a mechanically extracted nontoxic variety of oil (JCO) as source of energy for feedlot lambs. Twenty Pelibuey × Katahdin lambs were individually fed a dry-rolled-corn-based finishing diet supplemented with 0%, 2%, 4%, or 6% JCO (diet dry matter basis). Supplemental JCO replaced dry rolled corn in the basal diet. Fatty acid composition of JCO was C16:0, 14.0%; C18:0, 8.2%; C18:1, 26.0%; C18:2, 50.3%, and C18:3, 0.4%. Daily intakes of JCO averaged 24.7, 51.1, and 77.3 g/day or 0.57, 1.08, and 1.62 g/kg LW for the 2%, 4%, and 6% levels of supplementation, respectively. Supplemental JCO did not affect ( = 0.33) dry matter intake (DMI), but tended to increase (linear effect, = 0.06) average daily gain, efficiency of gain (linear effect, < 0.01), and dietary net energy (linear effect, < 0.01) and decreased (linear effect, < 0.01) the ratio of observed/expected DMI. At low levels (20 g/kg diet dry matter) of supplementation, the net energy (NE) value of JCO corresponds closely (0.99) to the NE value assigned by current standards (), and this NE value decreased linearly as the inclusion level of JCO increased. There were not treatment effects on plasma metabolites. Across treatments, the concentrations of hemoglobin (11.64 ± 1.08 g/dL), hematocrit (39.15 ± 3.67%), glucose (85.2 ± 17.64 mg/dL), creatinine (1.43 ± 0.28 mg/dL), and urea (20.70 ± 4.35 mg/dL) were within normal (9-15 g/dL, 27%-40%, 50-90 mg/dL, 1.0-1.8 mg/dL, and 15-50 mg/dL, for hemoglobin, hematocrit, glucose, creatinine, and urea, respectively) ranges for healthy lambs. Based on DMI, performance and plasma metabolites observed in this study, nontoxic JCO is a suitable source of energy in finishing diets for lambs.

Influence of growing phase feed efficiency classification on finishing phase growth performance and carcass characteristics of beef steers fed different diet types

A 5-yr study was conducted using 985 crossbred steers (464 kg [SD 32]) fed in 6 separate, replicated groups to determine the influence of growing phase (GP) feed efficiency (FE) classification and diet type on finishing phase (FP) FE of steers. During the GP at the University of Missouri, steers were fed either a whole shell corn-based diet (G-Corn; 528 steers) or a roughage-based diet (G-Rough; 457 steers) using GrowSafe feed bunks to measure DMI for 69 to 89 d. At the end of the GP, steers were ranked by residual feed intake (RFI) within diet, shipped to Iowa State University, and blocked into FP pens (5 to 6 steers/pen) by GP diet and RFI rank (upper, middle, or lower one-third). Steers were transitioned to either FP cracked corn- or byproduct-based diets and fed until 1.27 cm backfat was reached. After completion of the sixth group, average GP G:F within GP diet was calculated for each FP pen (168 total pens) using GP initial BW as a covariate (G-Corn: 0.207 [SD 0.038]; G-Rough: 0.185 [SD 0.036]). Pens were classified as highly feed efficient (HFE; >0.5 SD from the G:F mean; 58 pens), mid feed efficient (MFE; ±0.5 SD from the G:F mean; 60 pens), or lowly feed efficient (LFE; <0.5 SD from the G:F mean; 50 pens). Data were analyzed using PROC MIXED of SAS. Experimental unit was FP pen and the model included the fixed effects of GP diet, FE classification, FP diet, and the interactions. Group (1 to 6) was included as a fixed effect. There were no 3-way interactions ( ≥ 0.2) for any measured traits. Finishing phase G:F was not affected by any interactions ( ≥ 0.5) but was greater ( ≤ 0.03) for HFE versus MFE and LFE and greater ( = 0.02) for MFE versus LFE. Growing phase diet × FE classification effects were detected ( ≤ 0.01) for FP final BW (FBW), ADG, and DMI. Among G-Rough steers, HFE and MFE had greater ( ≤ 0.04) FBW and ADG than LFE, but among G-Corn steers, LFE had heavier ( = 0.03) FBW than HFE whereas ADG was unaffected ( ≥ 0.2) by FE classification. Dry matter intake was unaffected ( ≥ 0.3) by FE classification among G-Rough steers, but among G-Corn steers, LFE had greater ( ≤ 0.003) DMI than MFE and HFE. Overall, differences in FP G:F between FE classifications were driven by different factors depending on diet; ADG differed among roughage-grown steers and DMI differed among corn-grown steers. Ultimately, steers classified as HFE during the GP still had superior FE during the FP.

Effects of increased inclusion of algae meal on finishing steer performance and carcass characteristics

The deoiled residue from the production of heterotrophic microalgae can be combined with soyhulls to form a novel feedstuff called algae meal (ALG). To determine the effects of replacing corn in a finishing diet with ALG on growth, mineral status, carcass characteristics, and longissimus thoracis fatty acid profile, crossbred steers (168) were blocked by BW (432 ± 30.8 kg) into pens of 6 steers (7 pens per treatment). Pens received 1 of 4 diets: a corn-based control (CON), 14% ALG, 28% ALG (ALG28), and 42% ALG (ALG42). Corn was replaced by ALG on a DM basis. Steer BW were taken on d 0, 1, 28, 56, 74, 101, and 102, and steers were harvested on d 103. Pen was the experimental unit and DMI, ADG, and G:F data were analyzed as repeated measures. Two steers per pen were selected for sampling of blood and liver (d -1 and 96) and collection of rib steaks at harvest. There was a treatment by × time effect ( = 0.10) for overall DMI, where DMI linearly increased ( ≤ 0.008) across all time periods except Day 28 through, 56 when DMI was not different between ALG28 and ALG42. There was a treatment by time effect for ADG ( < 0.01), with ADG linearly decreasing ( ≤ 0.03) in the first and third month, not differing ( = 0.95) in the second month, and linearly increasing ( < 0.01) in the fourth month as ALG increased in the diet. Final BW and HCW did not differ ( ≥ 0.50) between CON- and ALG-fed cattle. There was a treatment × time effect for G:F ( < 0.01), with G:F linearly decreasing ( ≤ 0.01) in the first 3 mo as ALG increased in the diet, whereas G:F linearly increased ( < 0.01) in the fourth month. Based on steer performance, calculated dietary NEg linearly decreased ( < 0.01) as ALG increased in the diet. Yield grade linearly decreased ( = 0.02) and there was a tendency for dressing percent and 12th-rib back fat to linearly decrease ( ≤ 0.10) as ALG increased in the diet. Plasma Cu, Fe, and Mg concentrations were not different ( ≥ 0.31) in CON vs. ALG cattle; however, plasma Zn concentrations linearly increased ( = 0.03) as ALG increased in the diet. Total lipid, SFA, MUFA, and PUFA concentrations in the longissimus thoracis did not differ ( ≥ 0.13) between CON- and ALG-fed cattle. Interestingly, the atherogenic index linearly decreased ( < 0.01) as ALG increased in the diet. Algae meal may have a lesser energy value than corn; however, a minimal effect on carcass performance suggests ALG may serve as a potential replacement for corn in feedlot diets.

Influence of distillers grains resulting from a cellulosic ethanol process utilizing corn kernel fiber on nutrient digestibility of lambs and steer feedlot performance

Two experiments evaluated the effects on animal performance of traditional wet distillers grains (T-WDG) compared to cellulosic wet distillers grains (C-WDG) from a new process converting corn kernel fiber into cellulosic ethanol. The resulting coproduct has greater CP and decreased starch and ether extract (EE) concentrations (34.0% CP, 1.6% starch, 7.3% EE) compared to T-WDG (32.5% CP, 5.1% starch, 7.7% EE). In Exp. 1, 10 wethers (34.1 ± 2.35 kg, SD) were used in a replicated 5 × 5 Latin square to evaluate digestibility of DM, fiber, EE, and N. Diets including a corn-based control with 7.5% T-WDG and 7.5% C-WDG (CORN); 30% or 45% inclusion of T-WDG; and 30% or 45% inclusion of C-WDG. Between CORN, 30% T-WDG, 45% T-WDG, or 45% C-WDG, DMI was not different (P ≥ 0.11), but lambs fed 30% C-WDG had decreased (P ≤ 0.05) DMI compared to other diets. Compared to CORN and 30% T-WDG, DM digestibility was lesser ( P< 0.05) for 45% T-WDG or 30% C-WDG, while 45% C-WDG has lesser (P ≤ 0.05) DM digestibility than all other treatments. Digestibility of NDF was not affected by treatment (P= 0.13), and ADF digestibility was not different ( 0.21) between CORN, 30% T-WDG, 30% C-WDG, or 45% C-WDG. However, digestibility of ADF tended to differ (P = 0.06) between 30% T-WDG and 45% C-WDG and was greater (P ≤ 0.05) in lambs fed 45% T-WDG compared to other treatments. In Exp. 2, 168 steers (421 ± 23.9 kg, SD) were used in a randomized complete block design to determine the impact of C-WDG or T-WDG on growth performance and carcass characteristics. Diets included a corn-based control (CON), 30% T-WDG (TRAD), 30% C-WDG (CEL), and 18% C-WDG and 12% condensed corn distillers solubles (CEL+CCDS; = 7 pens of 6 steers/pen). Steers fed TRAD had improved (P ≤ 0.01) ADG, G:F, and HCW compared to steers fed the CON diet. No differences (P ≥ 0.16) in ADG and HCW were noted for steers fed CEL compared to TRAD; however, steers fed CEL had decreased (P = 0.01) G:F due to increased (P = 0.02) DMI compared to TRAD-fed steers. Steers fed CEL or CEL+CCDS did not differ (P = 0.50) in G:F, but CEL+CCDS-fed steers had lesser (P ≤ 0.01) DMI and ADG likely due to greater S content of the CEL+CCDS diet. Overall, while DM digestibility of lambs fed 30% C-WDG was lesser than 30% T-WDG, performance of steers finished on C-WDG was similar to those fed T-WDG. However, WDG from the secondary fermentation appeared to have lesser energy than T-WDG, while maintaining similar cattle performance to corn-fed controls.

Effects of Replacing Dry-rolled Corn with Increasing Levels of Corn Dried Distillers Grains with Solubles on Characteristics of Digestion, Microbial Protein Synthesis and Digestible Energy of Diet in Hair Lambs Fed High-concentrate Diets

Four male lambs (Katahdin; average live weight 25.9±2.9 kg) with “T” type cannulas in the rumen and proximal duodenum were used in a 4×4 Latin square experiment to evaluate the influence of supplemental dry distillers grain with solubles (DDGS) levels (0, 10, 20 and 30%, dry matter basis) in substitution for dry-rolled (DR) corn on characteristics of digestive function and digestible energy (DE) of diet. Treatments did not influence ruminal pH. Substitution of DR corn with DDGS increased ruminal neutral detergent fiber (NDF) digestion (quadratic effect, p<0.01), but decreased ruminal organic matter (OM) digestion (linear effect, p<0.01). Replacing corn with DDGS increased (linear, p≤0.02) duodenal flow of lipids, NDF and feed N. But there were no treatment effects on flow to the small intestine of microbial nitrogen (MN) or microbial N efficiency. The estimated UIP value of DDGS was 44%. Postruminal digestion of OM, starch, lipids and nitrogen (N) were not affected by treatments. Total tract digestion of N increased (linear, p = 0.04) as the DDGS level increased, but DDGS substitution tended to decrease total tract digestion of OM (p = 0.06) and digestion of gross energy (p = 0.08). However, it did not affect the dietary digestible energy (DE, MJ/kg), reflecting the greater gross energy content of DDGS versus DR corn in the replacements. The comparative DE value of DDGS may be considered similar to the DE value of the DR corn it replaced up to 30% in the finishing diets fed to lambs.

Feed Value of Supplemental Fats Used in Feedlot Cattle Diets

The inclusion of supplemental fats in growing-finishing diets for feedlot cattle also improves diet "condition." Quality factors that may influence the feeding value of fat include the source of fat; moisture, impurities, and unsaponifiables; free fatty acid concentration; degree of saturation or titer; and rancidity (peroxide value). The net energy value of fat declines linearly with an increasing level of supplementation because of constraints on postruminal fatty acid digestion. The authors recommend that receiving diets not contain more than 2% supplemental fat. Little evidence suggests that the feeding value of fat is different for Holsteins than for conventional beef breeds. Fat supplementation is not consistent in its effect on intramuscular fat distribution (marbling), longissimus (rib eye) area, and fat thickness, but can be expected to increase dressing percentage and kidney, pelvic, and heart fat percentage.

Performance and ruminal fermentation of dairy cows fed whole cottonseed with elevated concentrations of free fatty acids in the oil

Twenty-four lactating Holstein cows were used in an 8-wk completely randomized design trial to examine the effects of feeding whole cottonseed (WCS) with elevated concentrations of free fatty acids (FFA) in the oil on intake and performance. Treatments included WCS with normal concentrations of FFA (6.8%, control) and 2 sources of WCS with elevated FFA [HFFA1 (24.1%) or HFFA2 (22.3%)]. The 2 sources of WCS with elevated FFA differed in that HFFA2 were discolored from being initially stored with excess moisture, which led to heating and deterioration during storage, whereas HFFA1 were normal in appearance and the increase in FFA occurred without heating and visible damage to the WCS. Nutrient concentrations were similar among WCS treatments, which provided 14% of the total dietary dry matter. Dry matter intake tended to be higher for cows fed HFFA2 compared with control and HFFA1. Yield of milk and components was similar among treatments, but milk fat percentage was lower for HFFA1 and HFFA2 compared with control. In a concurrent 3 x 3 Latin square trial with 6 ruminally cannulated Holstein cows, molar proportions of isobutyrate were higher for HFFA2 than control and HFFA1, but no differences were observed in acetate or propionate. Results of these trials indicate that feeding WCS with high concentrations of FFA decreases milk fat percentage but does not alter dry matter intake, milk yield, or concentrations of other components. The minor changes in ruminal fermentation that were observed do not account for the decrease in milk fat percentage.

Effects of adding poultry fat in the finishing diet of steers on performance, carcass characteristics, sensory traits, and fatty acid profiles

Use of poultry fat in the finishing diets of steers has not been studied as a potential source of added energy. Therefore, 60 Angus crossbred steers were fed 1 of 3 dietary treatments consisting of 1) a corn-soybean meal control diet devoid of added fat; 2) the control diet formulated with 4% tallow; or 3) the control diet formulated with 4% poultry fat. Addition of fat did not (P = 0.17) affect ADG for the 112-d study. The inclusion of tallow in the diet reduced (P < 0.05) ADFI of steers compared with those on the control diet; however, ADFI of steers fed poultry fat did not differ from those fed the control (P = 0.06) or the tallow (P = 0.36) diets. At d 55, steers consuming either fat source had improved (P < 0.05) G:F compared with steers fed the control diet. For the entire 112 d, steers consuming the poultry fat diet gained more efficiently (P < 0.05) than the control steers, and the tallow-fed steers were intermediate and not different from the other groups (P > or = 0.14). The inclusion of fat in the diet did not (P > or = 0.15) affect carcass characteristics. Steaks from the steers consuming diets with added fat were darker (lower L* value; P < 0.05) than the controls; however, dietary treatments did not (P > or = 0.10) affect any other objective color measurements or discoloration scores during retail display. Thiobarbituric acid reactive substances for LM steaks did not differ (P = 0.21) by dietary treatment. The cooked LM steaks from steers fed poultry fat did not (P > or = 0.80) differ in juiciness or flavor intensity from steaks of steers fed the control or tallow diets. There were also no differences (P = 0.18) in off flavors as a result of added dietary fat. In the LM and adipose tissue, percentages of total SFA were increased (P = 0.05) by adding supplemental fat to the diet, regardless of source. In the LM, total MUFA were decreased (P = 0.02) by adding supplemental fat. Conversely, diet did not (P > or = 0.14) affect the proportions of total PUFA in either tissue or total MUFA in the adipose tissue. Results indicated that replacing beef tallow in finishing diets with poultry fat, a more economical energy source, had no detrimental effects on growth performance, carcass characteristics, retail display life, fatty acid profiles, or palatability.

Effects of supplemental fat on growth performance and quality of beef from steers fed barley-potato product finishing diets: I. Feedlot performance, carcass traits, appearance, water binding, retail storage, and palatability attributes

To measure the effects of dietary fat on feedlot performance, carcass characteristics, and beef appearance, moisture binding, shelf life, and palatability, 168 crossbred beef steers (317 +/- 1.0 kg) were allotted randomly, within weight blocks, to a randomized complete block design with a 3 x2 + 1 factorial arrangement of dietary treatments. Main effects were level of yellow restaurant grease (RG; 0, 3, or 6%) and level of alfalfa hay (AH; 3.5 or 7%), with the added treatment of 6% tallow and 7% AH in barley-based diets containing 15% potato by-product and 7% supplement fed for 165 d (all dietary levels on a DM basis). Dietary treatment did not (P >0.10) affect DMI, LM area, beef brightness, or beef texture. Level of RG linearly increased (P <0.05) ADG from 1.48 to 1.60 kg/d, diet NE(m) from 2.4 to 2.6 Mcal/kg, diet NE(g) from 1.7 to 1.9 Mcal/kg, and internal fat from 2.1 to 2.4%. Level of RG linearly increased (P <0.05) G:F from 0.184 to 0.202, but decreased (P <0.05) beef firmness score from 3.0 to 2.8 and fat luster score from 3.1 to 2.8. Level of AH did not (P >0.10) affect any of the measurements; however, AH interacted with level of RG on fat thickness and yield grade (linear; P <0.05), as well as marbling score and percentage of carcasses grading USDA Choice (quadratic; P <0.05). Fat thickness and yield grade increased with increasing RG level in 3.5%, but not in 7%, AH diets. In steers fed 3.5% RG, marbling scores and percentage of carcasses grading Choice were greatest when fed with 3.5% AH, and least when fed 7% AH. Steers fed tallow had lower marbling scores (P = 0.01) and percentage of carcasses grading Choice (P = 0.066) than those fed RG. Retail storage attributes, including visual and instrumental color, decreased during storage (P <0.01), but were not (P >0.10) affected by diet. Trained sensory panel scores for initial tenderness increased quadratically (P = 0.07) as dietary RG increased, but diet did not (P >0.10) affect drip loss, cooking loss, or trained sensory panel scores for sustained tenderness, initial and sustained juiciness, and beef flavor. Therefore, RG increased diet energy, improved performance, and increased carcass fatness; however, dietary fat and AH did not affect most measurements of water retention, color stability, or palatability of beef.

Ruminal Fermentation and Amino Acid Flow in Holstein Steers Fed Whole Cottonseed with Elevated Concentrations of Free Fatty Acids in the Oil

The influence of feeding whole cottonseed (WCS) containing elevated concentrations of free fatty acids (FFA) in the oil on ruminal fermentation and amino acid (AA) flow to the abomasum was evaluated in a 4 x 4 Latin square trial. Four ruminally and abomasally cannulated Holstein steers were fed diets containing 12.5% of dry matter as WCS with concentrations of 8.0, 11.3, 14.7, or 18.0% FFA in the oil. Intake, ruminal digestibility, and flow to the abomasum of dry matter, organic matter, and acid detergent fiber were not affected by FFA level of WCS. Intake of neutral detergent fiber and total kilograms of neutral detergent fiber digested in the rumen were similar for all treatments. Ruminal neutral detergent fiber digestibility was lower for 8 and 14.7% FFA, resulting in a cubic effect on flow to the abomasum. Ruminal pH, molar proportions of isobutyrate, and total branched-chain volatile fatty acids (VFA) decreased linearly, whereas molar proportions of acetate and acetate:propionate ratio increased linearly as FFA in WCS increased. Total VFA were lower, and molar proportions of propionate were higher, for 8 and 14.7% FFA, resulting in a cubic effect. Intake of N, total N flow, and nonmicrobial N flow to the abomasum were similar among treatments. Flow of microbial N was lower for the 11.3% FFA treatment, resulting in a quadratic response. Only nonsignificant differences were observed in AA flow to the abomasum. Results of this trial indicate that WCS with FFA up to 18% may result in small changes in rumen fermentation.

Performance of Lactating Dairy Cows Fed Whole Cottonseed with Elevated Concentrations of Free Fatty Acids in the Oil

Twenty-four multiparous cows were used in a 10-wk randomized block design trial to evaluate the effects of feeding whole cottonseed (WCS) containing increasing concentrations of free fatty acids (FFA) in the oil on nutrient intake and digestibility, milk yield and composition, and select plasma metabolites. Two lots of WCS containing either 3 or 12% FFA were blended to provide WCS with 3, 6, 9, and 12% FFA. Cottonseeds were included in the wheat silage-based total mixed ration at 12.5% of dry matter (DM). There was no difference in intakes of DM, crude protein (CP), or neutral detergent fiber; yield of milk; or percentages of milk protein, lactose, or SNF. Milk fat percentage was lowest for the diet containing WCS with 6% FFA. Concentrations of individual milk fatty acids C6:0 decreased and C16:1 increased linearly as FFA in WCS increased. A cubic response was observed for concentrations of C8:0, C10:0, and C12:0 because of higher concentrations when diets contained WCS with 6% FFA than 3 and 12% FFA, which were higher than 9% FFA. Intake and apparent total tract digestibility of acid detergent fiber increased linearly as FFA concentration in WCS increased. Apparent NDF digestibility was highest for diets containing WCS with 3 and 6% FFA; CP digestibility was highest with WCS containing 3 and 9% FFA. Differences in milk fatty acid concentration and nutrient digestibility suggest minor changes in rumen fermentation; however, feeding WCS with up to 12% FFA did not negatively impact nutrient intake and digestibility or milk yield or composition.

Relationship between body weight and level of fat supplementation on fatty acid digestion in feedlot cattle

Eight Holstein steers with cannulas in the rumen and proximal duodenum were used in a split-plot design experiment to evaluate the interaction of body weight (175 vs. 370 kg) and level of fat supplementation (0, 3, 6, and 9% yellow grease) on characteristics of digestion and feeding value of fat in finishing diets. Dry matter intake was restricted to 2% of BW. There were no interactions between BW and level of fat supplementation (P > 0.10) on ruminal or total-tract digestion. Level of supplemental fat decreased (linear, P < 0.01) ruminal digestion of OM and NDF, and increased (linear, P < 0.05) ruminal N efficiency. There were no treatment effects (P > 0.10) on postruminal digestion of OM, NDF, and N. There tended to be an interaction (P < 0.10) between BW and level of fat supplementation on postruminal starch digestion. Increasing level of fat supplementation increased postruminal digestion of starch in heavier steers but did not affect starch digestion in lighter steers. There were no interactions (P > 0.10) between BW and level of fat supplementation on postruminal fatty acid digestion. Increasing level of fat supplementation decreased (linear, P < 0.01) postruminal fatty acid digestion, which was due to a decreased (linear, P < 0.01) postruminal digestion of C16:0 and C18:0. Supplemental fat decreased (linear, P < 0.01) total-tract digestion of OM and NDF. The estimated NEm (Mcal/kg) of yellow grease averaged (linear, P < 0.01) 6.02, 5.70, and 5.06 for the 3, 6, and 9% of level supplementation, respectively. We conclude that intestinal fatty acid digestion (FAD, %) is a predictable function (r2 = 0.89; P < 0.01) of total fatty acid intake per unit body weight (FAI, g/kg BW): FAD = 87.560 - 8.591FAI. Depressions in fatty acid digestion with increasing level of intake were due primarily to decreased intestinal absorption of palmitic and stearic acid. Level of fatty acids intake did not appreciably affect intestinal absorption of unsaturated fatty acid. Changes in intestinal fatty acid digestion accounted for most of the variation in the NE value of supplemental fat.