P.M. Walker

Space allowance and high fiber diet impact performance and behavior of group-kept gestating sows

Identifying and optimizing housing and management systems that improve the well-being of the gestating sow is essential to sustaining animal agriculture. Therefore, the impact of 2 floor-space allowances and a high-fiber gestation diet on dry group-housed sows were evaluated using multiple measures of well-being. Groups of 10 multiparous sows/pen (n = 221) were assigned randomly to treatments in a 2 × 2 factorial arrangement to either a corn-soybean meal diet (CTL) or corn-soybean meal diet supplemented with soybean hulls and wheat middlings (FBR), and floor-space allowance of either 1.7 or 2.3 m(2)/sow. Sow BW, backfat (BF), and body condition score (BCS) were all recorded on d 34, 65, 90, and 110 of gestation, whereas skin lesions were scored on d 34, every 2 d for the first 2-wk postmixing, and then biweekly throughout gestation. Blood sample was collected only on d 34 for cortisol (baseline), and samples were collected on d 90 of gestation for other measures including cortisol. Behavior was registered on multiple days throughout gestation. Sows fed FBR and kept at 1.7 m(2) produced heavier litter and weaning weights and greater number of piglets born alive, compared to sows fed FBR but kept at 2.3 m(2) of floor space (diet × floor space, P ≤ 0.04). Sows fed FBR and kept at 1.7 m(2) performed fewer oral-nasal-facial and sham-chew behaviors than sows fed CTL and kept at the same floor space (diet × floor space, P ≤ 0.044). Sows kept at 1.7 m(2) of floor space had a greater (P < 0.05) total lesion severity score than sows kept at 2.3 m(2)/sow, and vulva lesion scores were more (P < 0.02) severe among CTL-fed sows than FBR-fed sows. Parities 2 and 3 sows fed FBR and kept at 1.7 m(2) of floor space were heavier (P < 0.001) than sows fed the same diet but kept at 2.3 m(2). These results indicate that keeping small groups of pregnant sows at a minimum floor-space allowance of 1.7 m(2)/sow and floor feeding these sows a high-fiber diet can improve short-term sow well-being.

Effects of reduced-fat modified wet distillers grains with solubles on beef steer performance and carcass composition

Two experiments were conducted to examine feedlot performance and carcass characteristics of beef steers fed reduced-fat, modified wet distillers grains with solubles (RMDGS). Angus cross steers were stratified by BW in each experiment and assigned to 20 pens containing either 6 or 7 steers per pen. In Exp. 1, pens were randomly assigned to 1 of 4 diets containing 15% corn silage and 1) 25.0% RMDGS and 57.04% whole shelled corn (25 RMDGS); 2) 40.0% RMDGS and 42.69% whole shelled corn (40 RMDGS); 3) 70.0% RMDGS and 12.49% whole shelled corn, fed 84 d, then switched to 40 RMDGS (70/40 RMDGS); 4) 70.0% RMDGS and 12.49% whole shelled corn (70 RMDGS). In Exp. 2, the same diets were fed except 70/40 RMDGS was replaced with a diet containing 73.16% whole shelled corn and 9.60% soybean meal (0 RMDGS). In Exp. 1, no significant differences in DMI, ADG, G:F, or carcass characteristics were found. In Exp. 2, DMI increased (P = 0.003) with increasing RMDGS. In Exp. 2, LM samples from 2 steers in each pen at each slaughter date were analyzed. There were no differences (P > 0.05) in percentage of moisture, fat, or cooking loss in shear force of rib steaks among treatments. Steers fed the 70 RMDGS diet produced rib steaks with lower a* (P < 0.05) following 7 d of chilled storage. Fatty acid analysis showed an increase (P < 0.05) in SFA at the expense of MUFA because of RMDGS supplementation. Increases were observed in PUFA, PUFA/SFA, conjugated linoleic acid, and omega-6 fats, with increasing RMDGS. Steers fed 70 RMDGS had inconsistent feedlot performance with a trend for lighter HCW, lower QG, and reduced meat quality.

Effects of reduced-fat modified wet distillers grains with solubles on the performance of limit-fed beef cows1

ABSTRACT The objective of this study was to evaluate 3 inclusion rates for modified wet distillers grains with solubles containing 5.6 to 8.0% fat (WDGS) when limit-fed to beef cows during late gestation and early lactation. Angus × Simmental crossbred cows (n = 128) in the third trimester were blocked by parity (first parity and 2 or more parities) and stratified within parity by BW, subject to variation in BCS, to 16 pens. Four diets were fed until completion of a timed AI. Control cows were fed corn silage-, shelled corn-, and soybean meal-based diets to provide 12% CP [treatment (T) 1]. In the treatment diets, WDGS replaced shelled corn, soybean meal, and a portion of the corn silage to provide 12% (T2), 16% (T3), or 20% CP (T4). Analyzed CP values were 12.0, 12.5, 15.7, and 19.0%, for T1, T2, T3, and T4, respectively. Mean DMI per day was 7.80 ± 1.01, 7.96 ± 1.01, 8.55 ± 1.28, and 8.63 ± 1.11 kg for T1, T2, T3, and T4, respectively. No differences (P > 0.05) between treatments were observed for calving ease score, calf birth weight, calf BW, and cow BCS at the end of the feeding period. There was a linear (P = 0.03) increase in cow BW change in cattle fed increasing levels of WDGS and a quadratic response (P = 0.03) in milk production, with production increasing in T3 compared with T4 and T2 cattle. Cows fed increased levels of WDGS performed equally or superior to cows fed shelled corn- and soybean meal-based diets.

Effect of low-fat corn distillers grains fed at 40 and 70% inclusion on growth performance and meat quality of steers1

ABSTRACT Two trials were conducted to examine the effects of 40 and 70% inclusion rate of either dry or wet low-fat (6 to 8%) distillers grains on growth performance and meat quality. Trial 1 used dry distillers grains with solubles (DDGS) and 96 Angus steers. Trial 2 used wet distillers grains with solubles (WDGS) and 216 Angus steers. Steers were stratified by BW to pens, and pens were randomly assigned to 1 of 6 treatments formulated on a DM basis: 1) whole shelled corn, soybean meal, 15% corn silage, fed as a control (CON); 2) 40% DDGS or WDGS, whole shelled corn, 15% corn silage (C40); 3) C40 switched mid-trial to 70% DDGS or WDGS, whole shelled corn, 15% corn silage (40/70); 4) 70% DDGS or WDGS, whole shelled corn, 15% corn silage switched mid-trial to C40 (70/40); 5) CON + soybean meal, isonitrogenous to C40 (N40); 6) CON + corn oil, iso-fat to C40 (E40). In trial 1 DMI was greater (P = 0.02) for N40 and DDGS steers compared with CON for the first 84 d; DMI was lower (P = 0.01) for CON and 40/70 on 168 d. No significant DMI differences (P ≥ 0.32) were observed on d 213. In trial 2 no significant differences in DMI, BW, ADG, or G:F were observed across treatment diets at 142 d except N40-fed steers had reduced (P = 0.01) DMI compared with other treatments. Average daily gain, BW, and G:F at 56 d and 112 d were greatest (P = 0.001) for CON, N40, and E40 steers compared with steers receiving WDGS. Carcass characteristics were not negatively affected (P ≥ 0.06) by level of DDGS in either trial. Neither level of DDGS or WDGS nor CP or fat concentrations had a significant effect on meat quality, fatty acid composition, or lipogenic activity. According to this study, it is possible to increase the inclusion of low-fat DDGS and WDGS in feedlot rations as a percentage of dietary DM above 40%.

Predicting Carcass Composition in Early-Weaned Simmental Steers Using a Combination of Real-time Ultrasound, Live Evaluation, Carcass Expected Progeny Differences, and GeneSTAR Marbling Marker

Early-weaned Simmental steers (n = 192) were individually fed over 4 yr (48 head/ yr) to determine if real-time ultrasound (RTU), live evaluation, carcass expected progeny differences, GeneSTAR marbling, or a combination could accurately predict marbling composition. Steers were fed a high-concentrate diet for 249.7 ± 0.7 d and harvested at 423.3 ± 1.4 d of age. The RTU scans were recorded for ribeye area, intramuscular fat (IMF), and back fat thickness at 60-d intervals with final ultrasound scans taken ≤ 13 d prior to harvest. Yearling BW, marbling (MARB), percentage of retail cuts, and carcass weight expected progeny differences were calculated for each steer. Visual estimations of quality and yield grade were made ≤ 7 d prior to pre-harvest by 3 evaluators. Average price data over 5 yr were used for dressed beef, grid premiums, and discounts. GeneSTAR did not affect (P > 0.10) IMF deposition. Genetic, live, and carcass parameters were regressed on chemical IMF, dressed price, and profit using stepwise regression analysis. For chemically determined IMF, 67.0% of the variation was explained by RTU quality grade (R2 = 0.585), percentage of retail cuts (R2 = 0.030), and MARB (R2 = 0.028), indicating that RTU was the only major contributor. Approximately 17% of the variation in average dressed price was explained by RTU. GeneSTAR MARB marker was not an accurate indicator of intramuscular deposition of early-weaned Simmental steers; however, MARB expected progeny difference (EPD) was correlated to IMF deposition. Live evaluation better estimated yield grade than quality grade. Real-time ultrasound most accurately predicted MARB, carcass value, and profit.

Performance characteristics of beef cows program fed by-products from corn ethanol production1

The objective of this experiment was to evaluate the efficacy of programfed, corn-silage-based diets containing reduced-fat, modified wet corn distillers grains (RFDGS); high-fat, modified wet corn distillers grains (HFDGS); or highfat, condensed corn distillers solubles (HFCDS) containing 8.01, 10.53, and 10.99% ether extract (crude fat), respectively, on beef cow and calf performance. Angus × Simmental crossbred cows (n = 128) were program fed 1 of 4 dietary treatments for 206 d beginning in the third trimester through calf weaning. Cows were blocked by parity (first parity and 2 or more parities) and stratified within parity by BW subject to variation in BCS to 16 pens. Each block was equally represented within treatment. Control cows were fed diets based on corn silage, shelled corn, and soybean meal to provide 12.0% CP (T1). In treatment diets, corn silage and either RFDGS (T2) or HFDGS (T3) replaced shelled corn and soybean meal to provide 12.0% CP. High-fat, condensed distillers solubles (T4) replaced shelled corn and a portion of soybean meal to provide 12.0% CP. Cow DMI per day was lower (P = 0.01) for T3 comparing 10.13 ± 1.12, 9.88 ± 1.02, 8.07 ± 0.88, and 10.08 ± 1.20 kg for T1, T2, T3, and T4, respectively. Crude fat composition of the diets was different (P = 0.001), where T1 T2 and T3, T1 = T4, and T1 = T2 = T3. Milk urea nitrogen differed between treatments (P = 0.02), where T1 > T2 and T3, T4 = T1, and T4 = T2 = T3. No differences (P > 0.05) between treatments were observed for calf BW and cow BW and BCS at the end of the feeding period. Calf birth weight tended (P = 0.10) to be lower for T3 compared with T1, T2, and T4. In corn silage– based diets when beef cows are program fed to maintain similar BCS, HFDGS, RFDGS, and HFCDS can replace shelled corn and soybean meal, with similar performance.