Effects of diet form and feeder adjustment on growth performance of nursery and finishing pigs.

Three experiments were conducted to determine the effects of feeder adjustment and diet form on growth performance of nursery (Exp. 1 and 2) and finishing (Exp. 3) pigs. Treatments were arranged as a 2 × 3 factorial with the main effects of feeder adjustment and diet form. The 2 feeder adjustments were a narrow and wide feeder adjustment (minimum gap opening of 1.27 and 2.54 cm, respectively). The 3 diet forms were meal, poor-quality pellets (70% pellets and 30% fines for Exp. 1 and 2 and 50% pellets and 50% fines for Exp. 3), and screened pellets with minimal fines (3 to 10%). In Exp. 1, 210 pigs (initially 11.9 kg BW) were used in a 21-d trial with 7 pigs per pen and 5 pens per treatment. No feeder adjustment × diet form interactions were observed. There were no differences in ADG, ADFI, or G:F due to feeder adjustment. Pigs fed the meal diet had increased ( < 0.05) ADG and ADFI compared with pigs fed the poor-quality or screened pellets. Pigs fed meal or poor-quality pellets had decreased ( < 0.05) G:F compared with pigs fed screened pellets. In Exp. 2, 1,005 nursery pigs (initially 14.1 kg BW) were used in a 28-d trial with 26 to 28 pigs per pen and 6 pens per treatment. Pigs fed from the narrow feeder adjustment had decreased ( < 0.05) ADG and ADFI compared with pigs fed from the wide adjustment with no differences in G:F. Pigs fed the meal diet had decreased ( < 0.05) ADG compared with pigs fed poor-quality or screened pellets. Pigs fed meal or poor-quality pellets had decreased ( < 0.05) G:F compared with pigs fed screened pellets. In Exp. 3, 246 pigs (initially 56.8 kg BW) were used in a 69-d trial with 5 pens per treatment and 6 or 7 pigs per pen. Overall, ADFI decreased ( < 0.05) and G:F increased ( < 0.05) for pigs fed from the narrow adjusted feeders compared with the wide adjustment with no differences in ADG. Overall, pigs fed meal diets tended to have decreased ( < 0.10) ADG and had decreased ( < 0.05) G:F compared with pigs fed screened pellets; ADG and G:F in those fed poor-quality pellets were intermediate. Feeding meal or poor-quality pellets increased ( < 0.05) ADFI compared with pigs fed screened pellets. In conclusion, feeding nursery pigs from a wide feeder gap may increase ADG and ADFI with no negative effects on G:F. For finishing pigs, reducing feeder gap reduced feed disappearance and improved G:F. In all experiments, the greatest G:F improvements from pelleting were observed when the percentage of fines was minimized.

The effects of deoxynivalenol-contaminated corn dried distillers grains with solubles in nursery pig diets and potential for mitigation by commercially available feed additives.

Four experiments were conducted to investigate the effects of deoxynivalenol (DON) from naturally contaminated dried distillers grains with solubles (DDGS) and the efficacy of feed additives in nursery pig diets. In Exp. 1, 180 pigs (10.3 ± 0.2 kg BW) were fed 1 of 5 diets for 21 d. Diets were 1) Positive Control (PC; < 0.5 mg/kg DON), 2) Negative Control (NC; 4 mg/kg DON), 3) NC + 0.10% Biofix (Biomin Inc., Herzogenburg, Austria), 4) NC + 0.15% Cel-can (VAST Inc., Mason City, IA) and 0.50% bentonite clay, and 5) NC + 0.25% Defusion Plus (Cargill Animal Nutrition, Minneapolis, MN). Pigs fed the NC diet had poorer ( < 0.01) ADG than those fed the PC. Pigs fed Defusion Plus had improved ( < 0.03) ADG over those fed NC, whereas pigs fed Biofix or Cel-can with bentonite clay had reduced ADG ( < 0.01) compared with those fed PC. In Exp. 2, 340 pigs (11.7 ± 0.1 kg BW) were fed 1 of 8 diets for 21 d. Diets were 1) PC (< 0.5 mg/kg DON), 2) Low NC (1.5 mg/kg DON), 3) Low NC + 0.15% Biofix, 4) Low NC + 0.30% Biofix, 5) High NC (3.0 mg/kg DON), 6) High NC + 0.30% Biofix, 7) High NC + 0.45% Biofix, and 8) Diet 7 with 5% added water. Increasing the DON level reduced (linear; < 0.05) ADG, ADFI, and pig BW, and Biofix did not improve performance. In Exp. 3, 1,008 pigs (12.5 ± 0.3 kg BW) were fed 6 treatments for 24 d. Diets were 1) PC ( < 0.5 mg/kg DON), 2) NC (3 mg/kg DON), 3) NC + 0.25% Defusion, 4) NC + 0.50% Defusion, 5) Diet 3 with supplemental nutrients, and 6) Diet 5, pelleted. Pigs fed the NC had decreased ( < 0.01) ADG and ADFI, but adding Defusion improved (linear; < 0.04) ADG and ADFI over pigs fed NC. Pelleting improved ( < 0.01) both ADG and G:F, resulting in ADG above PC pigs. In Exp. 4, 980 pigs (12.0 ± 0.3 kg BW) were fed 1 of 7 diets in a 28-d trial in a 2 × 3 + 1 factorial arrangement. The 7 treatments were based on 3 diets fed in meal or pellet form: 1) PC (< 0.5 mg/kg DON), 2) NC (3 mg/kg DON), and 3) NC + 0.25% Defusion. Treatment 7 was Diet 3 with supplemental nutrients in pellet form. No interactions were observed between pelleting and Defusion. Pigs fed the NC had decreased ( < 0.01) ADG and ADFI, and pelleting improved ( < 0.01) ADG to PC levels, driven by improved ( < 0.01) G:F. Adding nutrients or Defusion had no effect. Overall, these studies show that Defusion and pelleting can help overcome some of the negative effects of DON, whereas other feed additives and additional nutrients do not.

Effects of supplemental vitamin D3 on serum 25-hydroxycholecalciferol and growth of preweaning and nursery pigs.

Four experiments were conducted to investigate the effects of varying concentrations of supplemental vitamin D3 on pig growth, feed preference, serum 25-hydroxycholecalciferol [25(OH)D3] , and bone mineralization of nursing and weanling pigs. In Exp. 1, 270 pigs (1.71 ± 0.01 kg BW) were administered 1 of 3 oral vitamin D3 dosages (none, 40,000, or 80,000 IU vitamin D3) on d 1 or 2 of age. Increasing oral vitamin D3 increased serum 25(OH)D3 on d 10 and 20 (quadratic, P < 0.01) and d 30 (linear, P < 0.01). No differences were observed in ADG before weaning or for nursery ADG, ADFI, or G:F. Vitamin D3 concentration had no effect on bone ash concentration or bone histological traits evaluated on d 19 or 35. In Exp. 2, 398 barrows (initially 7 d of age) were used in a 2 × 2 split plot design to determine the influence of vitamin D3 before (none or 40,000 IU vitamin D3 in an oral dose) or after weaning (1,378 or 13,780 IU vitamin D3/kg in nursery diets from d 21 to 31 of age) in a 45-d trial. Before weaning (7 to 21 d of age), oral vitamin D3 dose did not influence growth but increased (P < 0.01) serum 25(OH)D3 at weaning (d 21) and tended (P = 0.08) to increase 25(OH)D3 on d 31. Increasing dietary vitamin D3 concentration from d 21 to 31 increased (P < 0.01) serum 25(OH)D3 on d 31. Neither the oral vitamin D3 dose nor nursery vitamin D3 supplements influenced nursery ADG, ADFI, or G:F. In Exp. 3, 864 pigs (initially 21 d of age) were allotted to 1 of 2 water solubilized vitamin D3 treatments (none or 16,516 IU/L vitamin D3 provided in the drinking water from d 0 to 10) in a 30-d study. Providing vitamin D3 increased serum 25(OH)D3 concentrations on d 10, 20, and 30; however, vitamin D3 supplementation did not affect overall (d 0 to 30) ADG, ADFI, or G:F. In Exp. 4, 72 pigs were used in a feed preference study consisting of 2 feed preference comparisons. Pigs did not differentiate diets containing either 1,378 or 13,780 IU vitamin D3/kg but consumed less (P < 0.01) of a diet containing 44,100 IU vitamin D3/kg compared with the diet containing 1,378 IU vitamin D3/kg. Overall, these studies demonstrate that supplementing vitamin D3 above basal concentrations used in these studies is effective at increasing circulating 25(OH)D3, but the supplement did not influence growth or bone mineralization. Also, concentrations of vitamin D3 of 44,100 IU/kg of the diet may negatively affect feed preference of nursery pigs.

Technical note: Effect of determining baseline plasma urea nitrogen concentrations on subsequent posttreatment plasma urea nitrogen concentrations in 20- to 50-kilogram pigs.

Plasma urea N (PUN) has been used as an indicator of AA requirements and efficiency of AA utilization in swine. However, PUN concentrations vary among a population of pigs, even a population with a close range of BW and fed the same diet. Thus, pretreatment or baseline PUN concentrations are used as a covariate to reduce variation of posttreatment PUN. However, this procedure increases experimental costs and stress to the pigs. Data from 14 experiments (26 to 28 d in duration) conducted using PUN as a response variable were compiled into 1 data set. Each experiment had 4 to 6 treatments. The purpose of this technical report was to summarize the effect of determining pretreatment baseline PUN concentrations on subsequent posttreatment PUN concentrations in 20- to 50-kg pigs. In all experiments, pigs were fed corn- and soybean meal-based diets and low-CP diets with various AA additions; pigs were assigned to dietary treatments in a randomized complete block design with a minimum of 4 replicates of 3 to 5 pigs each. Before the start of each experiment, all pigs were fed a common diet for a minimum of 3 d. Blood samples were collected from each pig before allotment to dietary treatments (d 0) and at the end of each experiment. The baseline (d 0) PUN was analyzed as a covariate for posttreatment PUN. Data from each experiment were analyzed without and with baseline PUN in the statistical model. In all experiments combined, there were 768 possible treatment comparisons. The covariate baseline PUN was statistically significant (P < 0.10) in 9 of 14 experiments. However, only 8 treatment differences changed statistical significance as a result of analyzing the data with baseline PUN as a covariate. These 8 treatment differences were in 3 experiments. These results indicate that it is not always necessary to determine baseline PUN concentrations when feeding diets with large differences in AA content.

Effect of incremental levels of red blood cells on growth performance and carcass traits of finishing pigs.

Three experiments were conducted to determine the effect of incremental levels of red blood cells (RBC; 0 to 4%, Exp. 1; 0 to 2%, Exp. 2 and 3) on growth performance and carcass traits of finishing pigs. Dietary treatments were formulated to meet or exceed the nutrient requirements of barrows and gilts gaining 350 g of lean BW gain per day and were formulated to contain 0.52% apparent ileal digestible (AID) Lys for barrows and 0.59% AID Lys for gilts. In Exp. 1, barrows and gilts (2 replicates of barrows and 2 of gilts; 4 pigs per pen) were fed 0, 1, 2, 3, or 4% RBC. Initial BW (mean +/- SD) was 84.6 +/- 4.9 and 82.42 +/- 4.8 kg, and final BW was 118.7 +/- 6.5 and 120.0 +/- 9.6 kg for barrows and gilts, respectively. Two barrows and 2 gilts per pen were randomly selected and slaughtered for collection of carcass measurements. Experiment 2 was similar to Exp. 1, except 0, 1, or 2% RBC were added. Initial BW was 82.5 +/- 6.4 and 79.2 +/- 7.0 kg, and final BW was 125.5 +/- 6.2 and 119.8 +/- 8.8 kg for barrows and gilts, respectively. Each dietary treatment had 4 replicates per sex with 4 pigs per pen. One barrow and 1 gilt per treatment replicate were randomly selected and slaughtered for collection of carcass traits and viscera weights. Experiment 3 was similar to Exp. 2 except only barrows were used, and the initial and final BW were 86.0 +/- 5.7 and 133.4 +/- 8.4 kg, respectively. Each dietary treatment had 4 replicates with 3 pigs per pen, and all pigs were slaughtered for collection of carcass traits and viscera weights. In Exp. 1, final BW, ADG, and G:F were decreased linearly (P < 0.01 to 0.10) as RBC addition increased, but ADFI was not affected. With increased RBC addition, average backfat increased (P < 0.09) and fat free lean decreased (P < 0.04). There was a quadratic effect (P < 0.04) on dressing percentage (DP); the 2% RBC addition increased DP, but the 3 and 4% additions decreased DP. The RBC addition had no effect (P > 0.10) on any remaining carcass measurements. In Exp. 2, there was a quadratic effect (P < 0.07) of RBC addition on average backfat; the 1% RBC addition decreased backfat, but the 2% addition returned backfat to the level of the control pigs. There was no effect (P > 0.10) on any other response variable. In Exp. 3, with increased RBC addition, average backfat linearly decreased (P < 0.04) and large intestine percentage increased (P < 0.09). There was no effect of RBC addition (P > 0.10) on any other response variable. Our data indicate that feeding 3 or 4% RBC decreases growth performance of finishing pigs. However, feeding 1 or 2% RBC to finishing pigs had no detrimental effects on growth performance and increased DP in one experiment.

Effects of dietary spray-dried plasma protein on sow productivity during lactation.

Seventy-two primiparous and multiparous sows (36 per dietary treatment) farrowed in 4 groups were used to evaluate the effects of spray-dried plasma protein (SDP) on sow and litter performance during lactation. Dietary lactation treatments consisted of a corn-soybean meal control and a corn-soybean meal diet containing 0.5% SDP. Both diets were formulated to contain 1.0% total Lys and 3.46 Mcal/kg of ME and were fed from d 107 +/- 1.2 of gestation to weaning. Sows were allotted to dietary treatment based on breed, parity, and the date of d 107 of gestation. Litters were standardized within diet, and pigs were weaned at an average age of 19 +/- 2.1 d. Sows were fed 3 times daily during lactation. After weaning, sows were fed a common gestation diet and checked twice daily for estrus. Sows were grouped by parity (young sows, 3) for statistical analysis. The data were analyzed as a 2 x 2 factorial arrangement of treatments; the factors were parity (3) and SDP (0 or 0.5%). Treatment differences were considered significant at P < 0.10. Mature sows had a greater BW on d 107 of gestation, on d 1 postfarrowing, and at weaning; greater lactation ADFI; and greater litter BW after cross-fostering, but pig survival to weaning was decreased. Sows fed SDP had a greater gestation interval, litter BW at weaning, and litter ADG, with 1 less lactation day. The effect of SDP addition was dependent on sow parity, as noted by numerous SDP x parity interactions. The addition of SDP increased lactation ADFI in mature sows but decreased ADFI in young sows. Mature sows fed SDP had a greater number of pigs weaned per litter, litter and pig weaning weights, pig survival to weaning, and number of pigs weaned per litter weighing more than 3.6 kg, but the SDP diet had little to no effect on these responses in young sows. Subsequent farrowing data were collected, but no dietary treatment effects (P > 0.10) were observed. The results of this research indicate that SDP increased productivity of sows in parity 4 or greater.