Effects of Increasing the Energy Density of a Lactating Ewe Diet by Replacing Hay with Soyhulls (SH) and Dried Distillers Grains with Solubles (DDGS)

Objectives: To evaluate the effects of increasing the ewe’s dietary energy by replacing hay with SH and DDGS on milk production, nutrient composition, lamb growth, and changes in ewe body weight and body condition score (BCS)

A Comparison of Corn or Soybean Hull Based Diets with Dried Distillers Grain with Solubles (DDGS) as the Protein Source in Finishing Diets Comparing Lamb Growth, Feed Efficiency, and Carcass Merit

Objectives: To evaluate growth, carcass merit and mineral status in wether lambs fed finishing diets formulated with dried distillers grain with solubles (DDGS) and soybean hulls (SH)

Effects of Increasing the Dietary Energy Density by Replacing Grass Hay with Soybean Hulls and Dried Distillers Grains with Solubles on Nutrient Digestibility and Rumen Fermentation

We hypothesize that soybean hulls (SH) and dried distillers grains with solubles (DDGS) can be used in lamb diets to increase dietary energy density compared with a traditional grass hay (GH) and soybean meal (SBM) diet without causing adverse effects on nutrient digestibility and rumen function. To test this hypothesis, four ruminally-cannulated wethers were used in a 4x4 Latin square design to determine the effects of replacing GH with SH and replacing SBM with DDGS on nutrient digestibility and rumen fermentation. All diets were formulated to contain 60% roughage and 40% concentrate on DM basis. Dietary roughage source, however, varied from completely GH to completely SH, and SBM was replaced by DDGS. Diets were formulated to contain 13.9% CP and an increasing amount of dietary energy as SH and DDGS replaced GH and SBM. The control diet was composed of 60% GH and 11.6% SBM (GH-SBM). Treatment diets were 60% GH and 25.4% DDGS (GH-DDGS); 20% GH, 40% SH, 15.3% DDGS (SH40-DDGS); or no GH, 60% SH, 10% DDGS (SH60-DDGS). The SH, protein concentrate, and mineral portion of the diet was pelleted and mixed with the chopped GH, when GH was included in the diet. The SH60-DDGS diet was a completely pelleted diet. This trial was divided into four periods. Lambs were allowed 14 d to adapt to their respective treatment diet which was offered twice daily. Following adaptation, total feed, fecal, and urine samples were collected and weighed during the 4-d collection period and subsequently composited for nutrient analyses. On the day following collection of fecal and urine samples, rumen fluid was collected at -2, 0, 1, 4, 8, 12 h relative to feeding, for analysis of VFA and ammonia concentrations. Replacing GH with SH improved DM digestibility and the DE content of the diet. Although increasing SH in the diet decreased rumen pH, ADF and NDF digestibility was not affected adversely. Lower rumen pH did favor increased propionate concentrations in the rumen. These data are consistent with the hypothesis that DDGS and SH can be used to increase the energy density of lamb diets compared to a traditional GH and SBM diet without affecting nutrient digestibility and rumen pH adversely

Effects of Increasing Dietary Energy Density by Replacing Hay with Soyhulls (SH) and Dried Distillers Grains with Solubles (DDGS) on Nutrient Digestibility and Rumen Physiology

Objectives: To determine the effects of increasing dietary energy density in lamb diets from soybean hulls (SH) and dried distillers grain with solubles (DDGS) on nutrient digestibility and rumen physiology

Effects of Increasing the Energy Density of a Lactating Ewe Diet by Replacing Grass Hay with Soybean Hulls and Dried Distillers Grains with Solubles

The objective of this experiment was to determine the effects of increasing the energy density of a lactating ewe diet by replacing grass hay (GH) with soybean hulls (SH) and replacing soybean meal (SBM) with dried distillers grains with solubles (DDGS) on ewe body condition, milk production and nutrient composition, and lamb performance. Sixteen 2-year-old ewes were selected based on a common lambing date. All diets contained 60% roughage and 40% concentrate. Dietary roughage source, however varied from completely GH to completely SH, and SBM was replaced by DDGS. Diets were formulated to contain 13.9% CP and an increasing amount of dietary energy as SH and DDGS replaced GH and SBM. The control diet for this experiment was composed of 60% GH and 11.6% SBM (GH-SBM). Treatment diets were 60% GH and 25.4% DDGS (GH-DDGS); 20% GH, 40% SH, 15.3% DDGS (SH40-DDGS); and no GH, 60% SH, 10% DDGS (SH60-DDGS). The SH, protein concentrate, and mineral portion of the diet was pelleted and mixed with the chopped GH, when GH was included in the diet. The SH60-DDGS diet was a completely pelleted diet. Ewes were offered feed twice daily, and a weigh-suckle-weigh technique was performed weekly throughout the 8-week lactation to quantify production and characterize nutrient composition milk in the ewe. Ewe BW and BCS was recorded at the beginning and end of the trial and lamb growth performance was monitored weekly. Replacing GH and SBM with SH and DDGS increased milk production without decreasing ewe BW and BCS during lactation. Although, total milk solids, protein, and fat were decreased when SH and DDGS replaced GH and SBM, lamb growth performance was improved. Increased milk production that resulted with the inclusion of SH and DDGS in the diet was sufficient to overcome the lesser nutrient composition of the milk to result in differences in lamb growth. These data are consistent with the hypothesis that replacing GH and SBM with SH and DDGS increases dietary energy density and results in increased milk production and lamb growth without compromising ewe BW and BCS

The Presence of Growth Hormone Secretagogue Receptor (ghrelin receptor) in Metabolic Tissues of Beef Cattle with Differences in Composition of Gain

Beef steers (n = 72) of similar age, weight (651 ± 3.1 lb), and genetic (Angus crossbred) background were used to determine the effects of growing diet composition (high‐forage vs. high‐concentrate) on the abundance of growth hormone secretagogue receptor (GHS‐R or ghrelin receptor) in metabolically important tissues of beef cattle. At trial initiation (d 0), 8 steers were harvested for initial carcass composition. The remaining 64 steers were allotted, by weight, to pen and treatment was assigned randomly. Treatments were 1) a high‐forage diet fed during the growing period (116 d) followed by a high‐concentrate diet during the finishing period (117‐209 d; GRW‐FNSH) or 2) a high‐concentrate diet fed for the duration of the trial (0‐209 d; FNSH‐FNSH). Steers were allowed ad libitum consumption regardless of dietary treatment. Eight steers per treatment were harvested on d 88, 116, 165, and 209. Immediately following harvest, liver, muscle (sternomandibularis), and subcutaneous adipose tissue samples were collected from each steer and immersed in liquid nitrogen. Longissimus dorsi samples were collected following a 48 h chill to establish a preliminary analysis of GHS‐R abundance within an economically important muscle tissue. Protein separation and quantification was determined using SDSPAGE and Western blotting techniques. Protein abundance was detected using the LI‐COR® system and standardized to β‐Actin. Protein abundance data were analyzed statistically using the GLM procedure of SAS comparing diet, harvest date, and their interaction. Protein abundance of GHS‐R in longissimus dorsi tissue fluctuated relative to serial harvest date (P \u3c 0.001), and was highest on d 88 in both treatment groups. The FNSH‐FNSH steers had increased abundance of GHS‐R in longissimus dorsi on d 88 and 116 compared with the GRW‐FNSH steers. A dietary treatment by serial harvest day interaction (P \u3c 0.05) occurred for protein abundance of GHS‐R in subcutaneous adipose tissue. Abundance of GHS‐R in subcutaneous adipose tissue of the GRW‐FNSH was greatest on d 88, whereas abundance for the FNSHFNSH treatment was greatest at the end of the finishing period (d 209). An interaction of dietary treatment and serial harvest day resulted (P \u3c 0.05) for GHS‐R abundance in liver tissue. The GRW‐FNSH steers had increased liver GHS‐R abundance following realimentation compared with the FNSH‐FNSH steers which were on a continuous plane of nutrition. Protein abundance for liver GHS‐R in both dietary treatments increased quadraticly (P \u3c 0.001) throughout the feeding period. The GHS‐R was not detected in sternomandibularis tissue. Overall liver GHS‐R abundance increased in both dietary treatments following realimentation which is inconsistent with our hypothesis. Increased GHS‐R abundance in various tissues of beef cattle while ghrelin concentrations are high and excess fat deposition is occurring warrants further investigation

Effects of Dietary Energy Source and Corn Oil Inclusion on Plasma Metabolite and Lipid Profiles and Intramuscular Adipose and Muscle Accretion in Beef Cattle

The objectives of this research were to evaluate 1) fluctuations in plasma metabolites and lipid profiles and 2) differences in satellite cell differentiation and proliferation in cattle with differences in marbling relative to total fatness. Dietary starch is thought to optimize accumulation of marbling. In this experiment, readily fermentable fiber or corn oil were substituted for starch from corn in an effort to alter adipose tissue accretion. Crossbred yearling steers (n = 144) were used in a 131 d finishing trial. The trial was designed as a 3 x 2 factorial arrangement of dietary energy source by corn oil inclusion. Dietary energy sources were the high starch diet which contained 8.5% roughage and 81.2% corn or a higher fiber diet in which chopped, high moisture ear corn (43.7%) and dried corn gluten feed (18.2%) were substituted for corn. Corn germ was included in the diet to provide 0, 2, or 6% corn oil in both the starch and fiber diets. Growth performance and carcass characteristics were recorded and blood samples were collected from each animal on d 96 and 131 of the feeding trial. Previously reported carcass data indicated that dietary energy source (starch vs. fiber) did not influence carcass characteristics. However, as the percentage of corn oil increased with additional amounts of corn germ, marbling scores decreased (P \u3c 0.05) at a constant subcutaneous fat thickness. Compositional analyses support a tendency (P ≤ 0.10) for decreased marbling relative to total carcass fat. Feeding germ increases (P \u3c 0.05) in all components of serum cholesterol. Earlier in the feeding period, GERM also caused higher (P \u3c 0.05) circulating glucose and NEFA concentrations. A sub‐population of steers that were highest (n = 12) and lowest (n = 12) for the relationship of marbling to total carcass fatness (M2Ratio) were scrutinized more closely. Differences in M2Ratio were not associated with HCW or fatness, but were associated with marbling (P \u3c 0.001). Serum collected early in the feeding period from high M2Ratio steers resulted in higher (P \u3c 0.05) satellite cell proliferation and differentiation rates in vitro than serum from low M2Ratio steers. This response diminished with additional days on feed. These results indicate that dietary carbohydrate source has minimal influence on carcass fat distributions, but that dietary oil dramatically alters circulating metabolites and is antagonistic to the production goal of high marbling‐high cutability carcasses

Effects of glycerol and sire breed on growth and carcass traits of finishing wether lambs

Objectives: To evaluate crude glycerin as an energy source for finishing lambs and to determine the effect of sire breed on finishing lamb growth performance and carcass characteristics. In light of previous research, the hypothesis for this experiment was that glycerol would have an energy value similar to that of corn when fed in high concentrate diets to finishing lambs

Prolonged, Moderate Nutrient Restriction in Beef Cattle Results in Persistently-Elevated Plasma Ghrelin Concentrations

Four steers (BW 1281±28.2 kg) were used in a crossover design to determine the effects of prolonged, moderate energy and protein restriction on plasma ghrelin and GH concentrations. A common high-energy diet was offered at 240% of the intake necessary for BW maintenance (2.4xM) or 80% of the intake necessary for BW maintenance (0.8xM). As a common starting point, all steers were adjusted to 2.4xM during a 23-d pre-trial adaptation period. At initiation of period 1, 2 steers remained at 2.4xM, whereas intake for the remaining 2 steers was restricted to 0.8xM. Feed allotments were offered twice daily in equal aliquots at 0800 and at 2000 h. On 7, 14, and 21 d following initiation of restriction, serial blood samples were collected via indwelling jugular catheter at 15-min intervals throughout a 12-h feeding interval. Following period 1, steers were weighed and intake amounts were recalculated. Dietary treatments were switched between steer groups, 2.4xM intake was established, and sampling period II was initiated as described for period I. Plasma samples were assayed for ghrelin, GH, insulin (INS), and NEFA concentrations. Subsequent to analyses, hormone data were pooled by hour for statistical analyses. The energy and protein restriction resulted in decreased BW for 0.8xM (-108.9 lb) steers compared with 2.4xM (127.9 lb) steers. Body weight loss along with decreased plasma INS concentrations and elevated plasma NEFA and GH concentrations indicate that these steers were in a catabolic state and mobilizing body tissue stores to meet nutrient requirements not met by dietary intake. Plasma ghrelin concentrations also were elevated for the 0.8xM steers compared with those of 2.4xM steers throughout the 21-d treatment period. These data are consistent with the hypothesis that plasma ghrelin concentrations are elevated in cattle throughout a prolonged, moderate energy and protein restriction that result in a catabolic state

Plasma Ghrelin Concentrations of Beef Cattle Consuming a Similar Amount of Dietary Energy Supplied by Different Ingredients

Previous research demonstrated that restricting nutrient intake by decreasing DMI of a high-grain diet increased plasma ghrelin concentrations. Objectives of this experiment were to determine 1) whether dietary ingredient composition influenced plasma ghrelin concentrations when energy intake was similar, and 2) whether relationships existed between plasma ghrelin concentrations and plasma insulin, NEFA, and GH concentrations or end-products of carbohydrate fermentation in the rumen. Five steers (1290 ± 39.9 lb) were used in a crossover design with dietary treatments of 50% hay-50% concentrate (HAY) offered at an amount that would meet the steer’s NEm requirement plus supply an additional 3.5 Mcal of NEg daily, or a diet composed of 10% hay-90% concentrate but limit-fed to achieve an energy intake similar to that of the HAY steers (LFC). Feed was offered in equal aliquots twice daily. Period I: on d 21 following initiation of the dietary treatment, serial blood samples were collected via indwelling jugular catheter at 15-min intervals, and rumen fluid samples were collected hourly throughout a 12-h feeding interval. Following period I, steers were weighed, dietary treatments were switched between steer groups, and intake amounts were recalculated on the basis of period I ending BW. Period II adaptation and sampling was repeated as described for period 1. Plasma samples were assayed for ghrelin, insulin, GH, and NEFA concentrations. Rumen fluid was assayed for VFA concentrations and pH. Net energy for gain was similar between treatment groups (3.5 ± 0.04 Mcal NEg/d). However, a higher DMI was required by HAY steers compared with LFC steers (20.7 vs. 15.9 ± 0.13 lb) to achieve the same energy intake. Plasma ghrelin concentrations were similar for HAY and LFC steers (115 vs. 107 ± 3.3 pg/mL) despite differences in DMI and ingredient composition. Plasma GH, NEFA, and insulin concentrations also were similar regardless of dietary ingredient composition. Strong correlations between plasma ghrelin concentrations and other hormones and metabolites or end-products of carbohydrate fermentation did not result. These data are consistent with the hypothesis that ingredient composition and quantity of DMI do not influence plasma ghrelin concentrations of steers when energy intake is similar and steers are in positive energy balance