Effect of mannan oligosaccharides and fructan on growth performance, nutrient digestibility, blood profile, and diarrhea score in weanling pigs

A total of 150 weanling pigs [(Yorkshire × Landrace) × Duroc] with an average BW of 7.22 ± 0.80 kg (21 d of age) were used in a 28-d trial to determine the effects of dietary fructan and mannan oligosaccharides on growth performance, nutrient digestibility, blood profile, and diarrhea score in weanling pigs. Pigs were allotted randomly to 1 of 5 dietary treatments: 1) negative control (NC), basal diet; 2) positive control (PC), NC + 0.01% apramycin (165 mg/kg); 3) NC + 0.1% fructan (FC); 4) NC + 0.1% mannan oligosaccharide source (MO); and 5) NC + 0.05% fructan + 0.05% mannan oligosaccharide source (FM). There were 3 replications per treatment with 10 pigs per pen (5 barrows and 5 gilts). From d 0 to 14, ADG and ADFI of pigs fed the PC, MO, and FM diets were greater (P < 0.05) than pigs fed the NC diet. From d 15 to 28, there were no differences (P > 0.05) in ADG, ADFI, and G:F. During the overall period (d 0 to 28), pigs fed the MO diet had a greater ADG than pigs fed the NC diet (P < 0.05). Pigs fed the PC and MO diets increased ADFI (P < 0.05) compared with pigs fed the NC diet. However, no differences were detected among dietary treatments in G:F during the overall experimental period. On d 14, the apparent total tract digestibility (ATTD) of DM and N in pigs fed the PC, MO, and FM diets was greater (P < 0.05) than pigs fed the NC diet. The ATTD of DM increased (P < 0.05) in pigs fed the MO and FM diets compared with pigs fed the FC diet. However, at the end of the experiment, pigs fed the FM diet had a greater (P < 0.05) ATTD of DM compared with pigs fed the NC diet. Additionally, there were no differences in IgG, red blood cells, white blood cells, and lymphocyte counts among dietary treatments on d 0, 14, or 28. The diarrhea score in pigs fed the MO diet was reduced (P < 0.05) compared with pigs fed the NC diet. In conclusion, mannan oligosaccharides have a beneficial effect on growth performance and nutrient digestibility in weanling pigs. Furthermore, mannan oligosaccharides can decrease diarrhea score in weanling pigs.     

Effects of dietary energy density and lysine:calorie ratio on growth performance and carcass characteristics of growing-finishing pigs

We conducted two experiments to evaluate the effects of dietary energy density and lysine:calorie ratio on the growth performance and carcass characteristics of growing and finishing pigs. In Exp. 1, 80 crossbred barrows (initially 44.5 kg) were fed a control diet or diets containing 1.5, 3.0, 4.5, or 6.0% choice white grease (CWG). All diets contained 3.2 and 2.47 g of lysine/Mcal ME during growing (44.5 to 73 kg) and finishing (73 to 104 kg), respectively. Increasing energy density did not affect overall ADG; however, ADFI decreased and feed efficiency (Gain:feed ratio; G:F) increased (linear, P < .01). Increasing energy density decreased and then increased (quadratic, P < .06) skinned fat depth and lean percentage. In Exp. 2, 120 crossbred gilts (initially 29.2 kg) were used to determine the effects of increasing levels of CWG and lysine:calorie ratio fed during the growing phase on growth performance and subsequent finishing growth. Pigs were fed increasing energy density (3.31, 3.44, or 3.57 Mcal ME/kg) and lysine:calorie ratio (2.75, 3.10, 3.45, or 3.80 g lysine/Mcal ME). No energy density x lysine:calorie ratio interactions were observed (P > .10). Increasing energy density increased ADG and G:F and decreased ADFI of pigs from 29.5 to 72.6 kg (linear, P < .05). Increasing lysine:calorie ratio increased ADG and ADFI (linear, P < .01 and .07, respectively) but had no effect on G:F. From 72.6 to 90.7 kg, all pigs were fed the same diet containing .90% lysine and 2.72 g lysine/Mcal ME. Pigs previously fed with increasing lysine:calorie ratio had decreased (linear, P < .02) ADG and G:F. Also, pigs previously fed increasing CWG had decreased (linear, P < .03) ADG and ADFI. From 90.7 to 107 kg when all pigs were fed a diet containing .70% lysine and 2.1 g lysine/Mcal ME, growth performance was not affected by previous dietary treatment. Carcass characteristics were not affected by CWG or lysine:calorie ratio fed from 29.5 to 72.6 kg. Increasing the dietary energy density and lysine:calorie ratio improved ADG and G:F of growing pigs; however, pigs fed a low-energy diet or a low lysine:calorie ratio from 29 to 72 kg had compensatory growth from 72 to 90 kg.     

Evaluation of methods to reduce bacteria concentrations in spray-dried animal plasma and its effects on nursery pig performance

Four experiments with 1,040 weanling pigs (17 +/- 2 d of age at weaning) were conducted to evaluate the effects of spray-dried animal plasma source, drying technique, and methods of bacterial reduction on nursery pig performance. In Exp. 1, 180 barrows and gilts (initial BW 5.9 +/- 1.8 kg) were used to compare effects of animal plasma, animal plasma source, drying technique (spray-dried or freeze-dried), and plasma irradiation in nursery pig diets. From d 0 to 10, pigs fed diets containing irradiated spray-dried animal plasma had increased ADG and ADFI (P < 0.05) compared with pigs fed diets containing nonirradiated spray-dried animal plasma. Pigs fed irradiated animal plasma Sources 1 and 2 were similar in ADG and ADFI, but pigs fed animal plasma Source 1 had greater ADG (P < 0.05) than pigs fed animal plasma Source 2 and pigs not fed plasma. Pigs fed freeze-dried animal plasma had growth performance similar (P > 0.36) to pigs fed spray-dried animal plasma. Overall (d 0 to 24), pigs fed irradiated spray-dried animal plasma were heavier (P < 0.05) than pigs fed no animal plasma, whereas pigs fed nonirradiated spray-dried plasma were intermediate. In Exp. 2, 325 barrows and gilts (initial BW 5.8 +/- 1.7 kg) were used to compare the effects of irradiation or formaldehyde treatment of animal plasma and formaldehyde treatment of the whole diet. Pigs fed diets containing irradiated animal plasma had greater ADG (P < 0.05) than pigs fed nonirradiated plasma. Pigs fed formaldehyde-treated plasma had greater ADG and ADFI (P < 0.05) than pigs fed diets with either nonirradiated plasma or whole diet treated with formaldehyde. In Exp. 3 (360 barrows and gilts; initial BW 6.3 +/- 2.7 kg) and Exp. 4 (175 barrows and gilts; initial BW 6.1 +/- 1.7 kg), the irradiation of feed (high bacteria) and food-grade (low bacteria) animal plasma in nursery pig diets was examined. Pigs fed irradiated feed-grade plasma Product 2 had increased ADG (P < 0.05) compared with pigs fed nonirradiated plasma Product 2 and pigs fed the control diet without plasma. In Exp. 3 and 4, pigs fed irradiated food-grade plasma had growth performance similar to pigs fed nonirradiated food-grade plasma (P > 0.12). These studies indicate that bacterial reduction of feed-grade, but not food-grade animal plasma, improves nursery pig performance.     

Comparison of growth performance and zinc absorption, retention, and excretion in weanling pigs fed diets supplemented with zinc-polysaccharide or zinc oxide

Fifty weanling crossbred pigs averaging 6.2 kg of initial BW and 21 d of age were used in a 5-wk experiment to evaluate lower dietary concentrations of an organic source of Zn as a Zn-polysaccharide (Zn-PS) compared with 2,000 ppm of inorganic Zn as ZnO, with growth performance, plasma concentrations of Zn and Cu, and Zn and Cu balance as the criteria. The pigs were fed individually in metabolism crates, and Zn and Cu balance were measured on individual pigs (10 replications per treatment) from d 22 to 26. The basal Phase 1 (d 0 to 14) and Phase 2 (d 14 to 35) diets contained 125 or 100 ppm added Zn as Zn sulfate, respectively, and met all nutrient requirements. Treatments were the basal Phase 1 and 2 diets supplemented with 0, 150, 300, or 450 ppm of Zn as Zn-PS or 2,000 ppm Zn as ZnO. Blood samples were collected from all pigs on d 7, 14, and 28. For pigs fed increasing Zn as Zn-PS, there were no linear or quadratic responses (P > or = 0.16) in ADG, ADFI, or G:F for Phases 1 or 2 or overall. For single degree of freedom treatment comparisons, Phase 1 ADG and G:F were greater (P < or = 0.05) for pigs fed 2,000 ppm Zn as ZnO than for pigs fed the control diet or the diet containing 150 ppm Zn as Zn-PS. For Phase 2 and overall, ADG and G:F for pigs fed the diets containing 300 or 450 ppm of Zn as Zn-PS did not differ (P > or = 0.29) from pigs fed the diet containing ZnO. Pigs fed the diet containing ZnO also had a greater Phase 2 (P < or = 0.10) and overall (P < or = 0.05) ADG and G:F than pigs fed the control diet. There were no differences (P > or = 0.46) in ADFI for any planned comparison. There were linear increases (P < 0.001) in the Zn excreted (mg/d) with increasing dietary Zn-PS. Pigs fed the diet containing ZnO absorbed, retained, and excreted more Zn (P < 0.001) than pigs fed the control diet or any of the diets containing Zn-PS. In conclusion, Phase 2 and overall growth performance by pigs fed diets containing 300 or 450 ppm Zn as Zn-PS did not differ from that of pigs fed 2,000 ppm Zn as ZnO; however, feeding 300 ppm Zn as Zn-PS decreased Zn excretion by 76% compared with feeding 2,000 ppm Zn as ZnO.     

Effect of chito-oligosaccharide on growth performance, intestinal barrier function, intestinal morphology and cecal microflora in weaned pigs

A total of 180 weanling pigs (21 ± 3 d of age; 5.98 ± 0.04 kg) were used to investigate the effect of chito-oligosaccharide (COS) on growth performance, intestinal barrier function, intestinal morphology, and cecal microflora. Based on initial BW, gender and litter, the pigs were given 5 treatments during a 14-d feeding experiment, including a basal diet (control), 3 diets with COS supplementation (200, 400, or 600 mg/kg), and a diet with colistin sulfate (CSE) supplementation (20 mg/kg). Six randomly selected pigs from each treatment were used to collect serum, duodenal, jejunal, ileal, and cecal samples on d 7 and 14 postweaning. From d 1 to 7 postweaning, pigs fed COS or CSE had greater ADG and ADFI compared with the control pigs. From d 1 to 14, diets with either 400 or 600 mg/kg COS, or 20 mg/kg CSE increased (P < 0.05) ADG and G:F compared with the control diet. No significant differences were observed in ADG, ADFI, and G:F between the pigs fed COS and CSE. Pigs fed either 400 or 600 mg/kg COS, or 20 mg/kg CSE had less (P < 0.05) diamine oxidase (DAO) in the serum, but greater concentration of (P < 0.05) DAO in jejunal mucosa, than the control pigs on d 7 postweaning. Treatments did not affect villous height and crypt depth of the duodenum, jejunum, or ileum. Pigs fed COS at 400 mg/kg had greater (P < 0.05) concentration of Bifidobacteria and Lactobacilli in the cecum than pigs fed the control diet and CSE diet on d 7 postweaning. Supplementation of COS or CSE decreased (P < 0.05) the population of cecal Staphylococcus aureus compared with the control diet on d 7 postweaning. The number of cecal Bifidobacteria in pigs fed 600 mg/kg COS was greater (P < 0.05) than that of pigs fed the control diet or CSE diet on d 14 postweaning. No significant differences were observed in Escherichia coli counts in the cecum among treatments. The present results indicate that dietary supplementation of COS at 400 or 600 mg/kg promotes growth performance and improves gut barrier function, increases the population of Bifidobacteria and Lactobacilli, and decreases S. aureus in the cecum of weanling pigs.     

Utilization of spray-dried blood cells and crystalline isoleucine in nursery pig diets

Three experiments were conducted to evaluate spray-dried blood cells (SDBC) and crystalline isoleucine in nursery pigs. In Exp. 1, 120 pigs were used to evaluate 0, 2, 4, and 6% SDBC (as-fed basis) in a sorghum-based diet. There were six replicates of each treatment and five pigs per pen, with treatments imposed at an initial BW of 9.3 kg and continued for 16 d. Increasing SDBC from 0 to 4% had no effect on ADG, ADFI, and G:F. Pigs fed the 6% SDBC diet had decreased ADG (P < 0.01) and G:F (P = 0.06) compared with pigs fed diets containing 0, 2, or 4% SDBC. In Exp. 2, 936 pigs were used to test diets containing 2.5 or 5% SDBC (as-fed basis) vs. two control diets. There were six replicates of each treatment at industry (20 pigs per pen) and university (six pigs per pen) locations. Treatments were imposed at an initial BW of 5.9 and 8.1 kg at the industry and the university locations, respectively, and continued for 16 d. Little effect on pig performance was noted by supplementing 2.5% SDBC, with or without crystalline Ile, in nursery diets. Pigs fed the 5% SDBC diet without crystalline Ile had decreased ADG (P < 0.01), ADFI (P < or = 0.10), and G:F (P < 0.05) compared with pigs fed the control diets. Supplementation of Ile restored ADG, ADFI, and G:F to levels that were not different from that of pigs fed the control diets. In Exp. 3, 1,050 pigs were used to test diets containing 5, 7.5, or 9% SDBC (as-fed basis) vs. a control diet. There were six replicates of each treatment at the industry (20 pigs per pen) location and five replicates at the university (six pigs per pen) locations. Treatments were imposed at an initial BW of 6.3 and 7.0 kg at the industry and university locations, respectively, and continued for 16 d. Supplementation of 5% SDBC without crystalline Ile decreased ADG and G:F (P < 0.01) compared with pigs fed the control diet, but addition of Ile increased ADG (P < 0.01) to a level not different from that of pigs fed the control diet. The decreased ADG, ADFI, and G:F noted in pigs fed the 7.5% SDBC diet was improved by addition of Ile (P < 0.01), such that ADG and ADFI did not differ from those of pigs fed the control diet. Pigs fed diets containing 9.5% SDBC exhibited decreased ADG, ADFI, and G:F (P < 0.01), all of which were improved by Ile addition (P < 0.01); however, ADG (P < 0.05) and G:F (P = 0.09) remained lower than for pigs fed the control diet. These data indicate that SDBC can be supplemented at relatively high levels to nursery diets, provided that Ile requirements are met.     

Effects of exogenous enzyme supplementation to corn- and soybean meal-based or complex diets on growth performance, nutrient digestibility, and blood metabolites in growing pigs

Two experiments were conducted to determine the effects of dietary supplementation of exogenous enzymes on growth performance, apparent total tract digestibility (ATTD) of energy and nutrients, blood metabolites, fecal VFA, and fecal ammonia-N in growing pigs (Sus scrofa) fed a corn (Zea mays L.)- and soybean [Glycine max (L.) Merr.] meal (SBM)-based diet. In Exp. 1, 240 growing barrows (initial BW: 55.6 ± 0.9 kg) were randomly allotted to 5 treatments on the basis of BW. There were 4 replicates in each treatment with 12 pigs per replicate. The 5 treatments consisted of a corn-SBM-based control diet and 4 additional diets were similar to the control diet, with the exception that 0.05% β-mannanase (M), α-amylase + β-mannanase (AM), β-mannanase + protease (MPr), or α-amylase + β-mannanase + protease (AMP) was added to the diets, which were fed for 28 d. Pigs fed the AM, MPr, or AMP diet had greater (P < 0.05) ADG than pigs fed the control diet. Pigs fed the AMP diet also had greater (P < 0.05) ADG than pigs fed the M, AM, or MPr diet. Pigs fed the AMP diet had greater (P < 0.05) G:F than pigs fed the control diet. The G:F of the pigs fed the M, AM, or MPr diet were not different (P > 0.05) from the G:F in pigs fed the AMP or control diet. The ADFI, ATTD of nutrients, blood metabolites, and fecal VFA and ammonia-N concentrations were not different among treatments. In Exp. 2, 192 growing barrows (initial BW: 56.9 ± 1.0 kg) were allotted to 4 treatments. There were 4 replicates in each treatment with 12 pigs per replicate. Pigs were fed a corn-SBM-based diet (CSD) or a complex diet (CD) that contained corn, SBM, 3% rapeseed (Brassica napus L.) meal, 3% copra (Cocos nucifera L.) meal, and 3% palm (Elaeis guineensis Jacq.) kernel meal. Each diet was prepared without exogenous enzymes or with 0.05% AMP and all diets were fed for 28 d. The ADG and G:F of pigs fed the CSD were greater (P < 0.05) than pigs fed the CD. However, the type of diet had no effect on the ATTD of nutrients, blood metabolites, or fecal VFA and ammonia-N, and there was no diet × enzyme interaction for any of the measured variables. Supplementation of diets with exogenous enzymes resulted in greater (P < 0.05) ADG, G:F, ATTD of DM, GE, and CP, and blood urea nitrogen (BUN) concentration. These results indicate that supplementation of 0.05% of AMP enzymes to a corn-SBM diet or a complex diet may improve the performance of growing pigs.     

Effects of choice white grease or poultry fat on growth performance, carcass leanness, and meat quality characteristics of growing-finishing pigs.

Eighty-four crossbred gilts were used to evaluate the effects of dietary choice white grease (CWG) or poultry fat (PF) on growth performance, carcass characteristics, and quality characteristics of longissimus muscle (LM), belly, and bacon of growing-finishing pigs. Pigs (initially 60 kg) were fed a control diet with no added fat or diets containing 2, 4, or 6% CWG or PF. Diets were fed from 60 to 110 kg and contained 2.26 g lysine/Mcal ME. Data were analyzed as a 2 x 3 factorial plus a control with main effects of fat source (CWG and PF) and fat level (2, 4, and 6%). Pigs fed the control diet, 2% fat, and 4% fat had greater (P < 0.05) ADFI than pigs fed 6% fat. Pigs fed 6% fat had greater (P < 0.05) gain/feed (G/F) than pigs fed the control diet or other fat levels. Subcutaneous fat over the longissimus muscle from pigs fed CWG had more (P < 0.05) moisture than that from pigs fed PF. Feeding dietary fat (regardless of source or level) reduced (P < 0.05) the amount of saturated fats present in the LM. Similarly, 4 or 6% fat decreased (P < 0.05) the amount of saturated fats and increased unsaturated fats present in the bacon. No differences (P > 0.05) were observed for ADG, dressing percentage, leaf fat weight, LM pH, backfat depth, LM area, percentage lean, LM visual evaluation, LM waterholding capacity, Warner-Bratzler shear and sensory evaluation of the LM and bacon, fat color and firmness measurements, or bacon processing characteristics. Adding dietary fat improved G/F and altered the fatty acid profiles of the LM and bacon, but differences in growth rate, carcass characteristics, and quality and sensory characteristics of the LM and bacon were minimal. Dietary additions of up to 6% CWG or PF can be made with little effect on quality of pork LM, belly, or bacon.     

Effects of blood meal pH and irradiation on nursery pig performance

A total of 720 nursery pigs in three experiments were used to evaluate the effects of blood meal with different pH (a result of predrying storage time) and irradiation of spray-dried blood meal in nursery pig diets. In Exp. 1, 240 barrows and gilts (17 +/- 2 d of age at weaning) were used to determine the effects of blood meal pH (7.4 to 5.9) in diets fed from d 10 to 31 postweaning (7.0 to 16.3 kg of BW). Different lots of dried blood meal were sampled to provide a range in pH. Overall (d 0 to 21), pigs fed diets containing blood meal had greater ADG (P < 0.05) and ADFI (P < 0.05) than pigs fed diets without blood meal. Ammonia concentrations in blood meal rose as pH decreased. However, blood meal pH did not influence (P > 0.16) ADG, ADFI, or gain:feed (G:F). In Exp. 2, 180 barrows (17 +/- 2 d of age at weaning) were used to determine the effects of post drying pH (7.6 to 5.9) and irradiation (gamma ray, 9.5 kGy) of blood meal on growth performance of nursery pigs from d 5 to 19 postweaning (6.8 to 10.1 kg of BW). One lot of whole blood was isolated with 25% of the total lot dried on d 0, 3, 8, and 12 after collection to create a range in pH. Overall, pigs fed blood meal had improved G:F (P < 0.01) compared to pigs fed the control diet. Similar to Exp. 1, the ammonia concentration of blood meal increased with decreasing pH. Blood meal pH did not influence ADG, ADFI, or G:F (P > 0.21), but pigs fed irradiated blood meal (pH 5.9) had greater ADG and G:F (P < 0.05) than pigs fed nonirradiated blood meal (pH 5.9). In Exp. 3, 300 barrows (17 +/- 6 d of age at weaning) were used to determine the effects of blood meal irradiation source (gamma ray vs. electron beam) and dosage (2.5 to 20.0 kGy) on growth performance of nursery pigs from d 4 to 18 postweaning (8.7 to 13.2 kg of BW). Overall, the mean of all pigs fed blood meal did not differ in ADG, ADFI, or G:F (P > 0.26) compared to pigs fed the control diet without blood meal. Pigs fed irradiated blood meal had a tendency (P < 0.10) for increased G:F compared with pigs fed nonirradiated blood meal. No differences in growth performance were detected between pigs fed blood meal irradiated by either gamma ray or electron beam sources (P > 0.26) or dosage levels (P > 0.11). These studies suggest that pH alone as an indicator of blood meal quality is not effective and irradiation of blood meal improved growth performance in nursery pigs.     

Effects of dietary iodine value product on growth performance and carcass fat quality of finishing pigs

A total of 120 barrows (initial BW = 47.9 ± 3.6 kg; PIC 1050) were used in an 83-d study to determine the effects of dietary iodine value (IV) product (IVP) on growth performance and fat quality. Pigs were blocked by BW and randomly allotted to 1 of 6 treatments with 2 pigs per pen and 10 pens per treatment. Dietary treatments were fed in 3 phases and formulated to 3 IVP concentrations (low, medium, and high) in each phase. Treatments were 1) corn-soybean meal control diet with no added fat (low IVP), 2) corn-extruded expelled soybean meal (EESM) diet with no added fat (medium IVP), 3) corn-soybean meal diet with 15% distillers dried grains with solubles and choice white grease (DDGS + CWG; medium IVP), 4) corn-soybean meal diet with low CWG (medium IVP), 5) corn-EESM diet with 15% DDGS (high IVP), and 6) corn-soybean meal diet with high CWG (high IVP). On d 83, pigs were slaughtered and backfat and jowl fat samples were collected and analyzed. The calculated and analyzed dietary IVP values were highly correlated (r(2) = 0.86, P < 0.01). Pigs fed the control diet, EESM, or high CWG had greater (P < 0.05) ADG than pigs fed EESM + DDGS. Pigs fed the control diet had greater (P < 0.05) ADFI than pigs fed all other diets. Pigs fed EESM + DDGS and high CWG had improved (P < 0.05) G:F compared with pigs fed the control diet or DDGS + CWG. Pigs fed diets with DDGS had greater (P < 0.05) backfat and jowl fat IV, C18:2n-6, and PUFA and less SFA than pigs fed all other treatments. Pigs fed EESM had greater (P < 0.05) backfat and jowl fat IV, C18:2n-6, and PUFA than pigs fed the control diet, low CWG, or high CWG. Pigs fed low CWG or high CWG had greater (P < 0.05) jowl fat IV than control pigs. Feeding ingredients high in unsaturated fatty acids, such as DDGS and EESM, had a greater impact on fat IV than CWG, even when diet IVP was similar. Therefore, IVP was a poor predictor of carcass fat IV in pigs fed diets with different fat sources and amounts of unsaturated fats formulated with similar IVP. Dietary C18:2n-6 content was a better predictor of carcass fat IV than diet IVP.     

The effect of copper and fat addition to the diets of weanling swine on growth performance and serum fatty acids.

A 2 x 3 factorial experiment, encompassing three 28-d trials involving a total of 420 weanling pigs, was conducted to determine the effect of dietary Cu (5 or 250 ppm) and animal fat (0, 2.5, or 5%) on the performance and serum fatty acid profiles of weanling pigs. Pigs had ad libitum access to corn-soybean meal-based diets containing 10% whey and 5% fish meal and similar lysine:calorie ratios. Pigs were weighed and pen feed intakes were recorded weekly. Weekly blood samples were collected during the first two trials (n = 270) for serum fatty acid analysis. There was a Cu x fat interaction for ADG from d 1 to 14 (P less than .07) and over the 28-d experiment (P less than .05). The ADG of pigs fed 250 ppm of Cu increased, whereas the ADG of pigs fed 5 ppm of Cu was not affected as dietary fat increased. The addition of 250 ppm of CU increased (P less than .01) ADFI throughout the 28-d experiment. The addition of fat quadratically increased ADG (P less than .05) during d 14 to 28 and gain:feed ratios (P less than .01) during d 14 to 28 and over the 28-d experiment. The addition of fat decreased (P less than .05) the weight percentage of serum saturated fatty acids and increased (P less than .01) the weight percentage of serum monounsaturated fatty acids on d 28. The addition of 250 ppm of Cu decreased (P less than .01) the weight percentage of monounsaturated fatty acids on d 14 and 28.(ABSTRACT TRUNCATED AT 250 WORDS)     

Effects of increasing choice white grease in corn- and sorghum-based diets on growth performance, carcass characteristics, and fat quality characteristics of finishing pigs

A total of 120 pigs (60 barrows and 60 gilts; TR4 × PIC 1050; 54.4 kg initial BW) were used in an 83-d study to evaluate the effects of added fat in corn- and sorghum-based diets on growth performance, carcass characteristics, and carcass fat quality. Treatments were arranged in a 2 × 3 factorial with grain source (corn or sorghum) and added fat (0, 2.5, or 5% choice white grease; CWG) as factors. There were 2 pigs (1 barrow and 1 gilt) per pen and 10 replicate pens per treatment. Pigs and feeders were weighed on d 14, 22, 39, 53, 67, and 83 to calculate ADG, ADFI, and G:F. At the end of the trial, pigs were slaughtered and jowl fat and backfat samples were collected and analyzed for fatty acid profile. No interactions were observed for growth performance. Pigs fed sorghum-based diets had greater (P < 0.01) ADG than pigs fed corn-based diets. Adding CWG improved (linear, P < 0.01) ADG. Pigs fed corn-based diets tended to have greater (P < 0.09) carcass yield, 10th-rib backfat, and percentage lean than pigs fed sorghum-based diets. Adding CWG increased (linear, P = 0.02) 10th-rib backfat, tended to increase (linear, P = 0.08) HCW, and tended to decrease (linear, P = 0.07) percentage lean. There was no grain source × fat level interaction for iodine value (IV) in backfat, but an interaction (P = 0.03) was observed for IV in jowl fat. Adding CWG increased (P < 0.01) IV in jowl fat for pigs fed sorghum- and corn-based diets; however, the greatest increase was between 0 and 2.5% CWG in sorghum-based diets and between 2.5 and 5% CWG in corn-based diets. Pigs fed corn-based diets had less (P = 0.01) C18:1 cis-9 and MUFA but greater (P = 0.01) C18:2n-6, PUFA, and backfat IV than pigs fed sorghum-based diets. Increasing CWG in the diet increased (linear, P = 0.01) backfat IV. Of the 2 fat depots, backfat generally had a reduced IV than jowl fat. In summary, feeding sorghum-based diets reduced carcass fat IV and unsaturated fats compared with corn-based diets. As expected, adding CWG increased carcass fat IV regardless of the cereal grain in the diet.     

Effect of dietary copper source (cupric citrate and cupric sulfate) and concentration on growth performance and fecal copper excretion in weanling pigs

In each of two experiments, 924 pigs (4.99 kg BW; 16 to 18 d of age) were assigned to 1 of 42 pens based on BW and gender. Pens were allotted randomly to dietary copper (Cu) treatments that consisted of control (10 ppm Cu as cupric sulfate, CuSO4 x 5H2O) and supplemental dietary Cu concentrations of 15, 31, 62, or 125 ppm as cupric citrate (CuCit), or 62 (Exp. 2 only), 125 (Exp. 1 only), or 250 ppm as CuSO4. Live animal performance was determined at the end of the 45-d nursery phase in each experiment. On d 40 of Exp. 2, blood and fecal samples were collected from two randomly selected pigs per pen for evaluation of plasma and fecal Cu concentrations and fecal odor characteristics. In Exp. 1, ADG, ADFI, and G:F were increased (P < 0.05), relative to controls, when pigs were fed diets containing 250 ppm Cu as CuSO4. Pigs fed diets containing 125 ppm Cu as CuCit had increased (P < 0.05) ADG compared with pigs fed diets supplemented with 15 or 62 ppm Cu as CuCit. The ADG, ADFI, and G:F did not differ among pigs fed diets containing 125 and 250 ppm Cu as CuSO4 or 125 ppm Cu as CuCit. In Exp. 2, pigs fed diets containing 250 ppm Cu as CuSO4 had improved (P < 0.05) ADG, ADFI, and G:F compared with controls. In addition, ADG, ADFI, and G:F were similar when pigs were fed diets containing either 250 ppm Cu as CuSO4 or 125 ppm Cu as CuCit. Pigs fed diets containing 62 ppm Cu as CuSO4 or CuCit had similar ADG, ADFI, and G:F. Plasma Cu concentrations were not affected by dietary Cu source or concentration, but fecal Cu concentrations were increased (P < 0.05) as the dietary concentration of Cu increased. Pigs consuming diets supplemented with 125 ppm Cu as CuCit had fecal Cu concentrations that were lower (P < 0.05) than pigs consuming diets supplemented with 250 ppm Cu as CuSO4. Fecal Cu did not differ in pigs receiving diets supplemented with 62 ppm Cu as CuSO4 or CuCit. Odor characteristics of feces were not affected by Cu supplementation or source. These data indicate that 125 and 250 ppm Cu gave similar responses in growth, and that CuCit and CuSO4 were equally effective at stimulating growth and improving G:F in weanling pigs. Fecal Cu excretion was decreased when 125 ppm Cu as CuCit was fed compared with 250 ppm Cu as CuSO4. Therefore, 125 ppm of dietary Cu, regardless of source, may provide an effective environmental alternative to 250 ppm Cu as CuSO4 in weanling pigs.     

Effect of irradiation of individual feed ingredients and the complete diet on nursery pig performance

A total of 1,210 nursery pigs was used in two experiments to evaluate the effects of irradiation of typical nursery diet ingredients, specialty protein products, and the whole diet on nursery pig performance. In Exp. 1, 880 barrows and gilts (15 +/- 2 d of age at weaning) were used in two growth trials (14 d and 12 d for Trials 1 and 2, respectively) to determine the effects of individual ingredient and whole-diet irradiation on nursery pig performance. Overall (d 0 to 14 of Trial 1 and d 0 to 12 of Trial 2), ADG was greater (P < 0.05) for pigs fed irradiated animal plasma compared with pigs fed the control, the diet containing irradiated microingredients, and the diet that was manufactured and irradiated. Also, pigs fed irradiated soybean meal had greater (P < 0.05) ADFI compared with pigs fed the manufactured diet that was irradiated. Pigs fed the diet containing irradiated animal plasma had improved feed efficiency (G:F; P < 0.05) compared with those fed the diet with irradiated microingredients and when all ingredients were irradiated before manufacturing of complete feed. Finally, pigs fed irradiated corn, whey, fishmeal, soybean oil, microingredients, or if all ingredients or the whole diet were irradiated, had similar ADG, ADFI, and G:F (P > 0.12) to control pigs. In Exp. 2, 330 nursery pigs (20 +/- 2 d of age at weaning) were used to determine the effects of irradiation of commercially available specialty protein products in diets for nursery pigs. Overall, ADG was greater (P < 0.05) when pigs were fed diets containing nonirradiated spray-dried animal plasma and egg combination (SDAPE) and dried porcine digest (DPD) compared with pigs fed the control diet containing no specialty protein products. In addition, G:F was improved (P < 0.05) when pigs were fed diets containing nonirradiated SDAPE, DPD, spray-dried beef muscle (SDBM), and spray-dried whole egg (SDWE) compared with pigs fed the control diet. Pigs fed irradiated SDAPE and SDBM had greater (P < 0.05) ADG than pigs fed the nonirradiated forms. Pigs fed irradiated SDBM had improved (P < 0.05) G:F compared with pigs fed the nonirradiated form. In Exp. 1 and 2, an irradiation treatment level of 8.5 kGy was effective in reducing the total bacterial concentration of all ingredients evaluated, as well as the whole diet in Exp.1. Irradiation of certain ingredients, but not the complete diet, increased growth performance of nursery pigs.     

Effects of Acid LAC and Kem-Gest acid blends on growth performance and microbial shedding in weanling pigs

Weanling pigs with mean initial BW of 6.04 kg (Exp.1) and 5.65 kg (Exp. 2) and mean age at weaning of 18.2 d (Exp. 1) and 17.7 d (Exp. 2) were used in two 5-wk experiments (Exp. 1, n = 180; Exp. 2, n = 300) to evaluate the effects of an organic acid blend (Acid LAC, Kemin Americas Inc., Des Moines, IA) and an inorganic/organic acid blend (Kem-Gest, Kemin Americas Inc.) on weanling pig growth performance and microbial shedding. In Exp. 1, the 5 dietary treatments were 1) negative control, 2) diet 1 + 55 ppm carbadox, 3) diet 1 + 0.4% Acid LAC, 4) diet 1 + 0.2% Kem-Gest, 5) diet 1 + 0.4% Acid LAC and 0.2% Kem-Gest. In Exp. 2, the 6 dietary treatments were diets 1 through 4 corresponding to Exp. 1, plus 5) sequence 1: 0.4% Acid LAC for 7 d followed by 0.2% Kem-Gest for 28 d, and 6) sequence 2: 0.2% Kem-Gest for 7 d followed by 0.4% Acid LAC for 28 d. Pigs were housed at 6 (Exp. 1) or 10 (Exp. 2) pigs/pen. Treatments were fed throughout the experiment in 3 phases: d 0 to 7, d 7 to 21, and d 21 to 35. In Exp. 1, there were no differences (P > 0.05) in ADG, ADFI, or G:F among the dietary treatments at any time during the study. In Exp. 2, throughout the study, pigs fed carbadox (diet 2) and sequence 1 (diet 5) diets had the greatest ADG (d 0 to 35; 262, 294, 257, 257, 292, and 261 g/d, diets 1 through 6, respectively; P < 0.05), greater ADFI than all other acid treatments (P < 0.05), and tended to have greater ADFI than diet 1 (P < 0.10). Fecal pH, Escherichia coli concentrations, and Salmonella presence were determined at d 6, 20, and 34 for Exp. 1, and on d 32 for Exp. 2. For both experiments, there was no effect of treatment on the presence of fecal Salmonella (P > 0.10) at any sampling time. In Exp. 1, fecal E. coli concentrations for pigs fed the carbadox (P < 0.05) diet were greater than for pigs fed the combination diet with 0.4% Acid LAC and 0.2% Kem-Gest on d 34, and the pigs fed the negative control diet tended (P < 0.10) to have greater fecal E. coli concentrations than those fed the combination diet on d 34. In Exp. 2, fecal pH of pigs fed sequence 1 tended to be greater than fecal pH of pigs fed diet 1, diet 4, or sequence 2 (P < 0.10), but there was no dietary effect on fecal E. coli. In Exp. 1, growth performance of pigs fed the Acid LAC and Kem-Gest diets was similar to each other and to that of the carbadox-fed pigs. Adding the combination of 0.4% Acid LAC and 0.2% Kem-Gest to nursery pig diets reduced ADFI and pig growth rate. In Exp. 2, pigs fed the acid sequence of Acid LAC-Kem-Gest had similar growth performance to pigs fed carbadox, and this novel dietary acid sequence may have merit as a replacement for antibiotics in the nursery phase.     

Recombinant porcine somatotropin alters performance and carcass characteristics of heavyweight swine and swine fed alternative feedstuffs

The efficacy of recombinantly derived porcine somatotropin (rpST) in improving the performance and carcass characteristics of heavyweight finishing pigs was determined. In Study 1, 36 pigs were killed for determination of initial carcass composition at 102 kg, and 36 pigs each were given 0, 1.5, 3, 6, or 9 mg of rpST/d from 102 to 136 kg live weight. Corn-soybean meal diets fed contained 19.8% CP and greater than 1% lysine. Study 2 tested the effects of 3 mg/d on pigs for 4 wk from 84 kg BW fed a corn-soybean meal or a triticale-barley-peas diet. Performance variables (ADG, average daily feed intake [ADFI], and feed efficiency [FE]) were measured weekly. Treatment with rpST increased (P less than .01) ADG and FE and decreased (P less than .01) ADFI in both studies. In Study 1, leaf fat, backfat thickness, belly thickness, and carcass fat were all decreased (P less than .01) linearly by rpST. Loin eye area (LEA), total trimmed lean, and total protein content were increased quadratically (P less than .01). At the 3-mg dose, ADFI, ADG, and FE were 87, 130, and 137% of control, and LEA, backfat, total protein gain, and total fat gain were 107, 80, 136, and 52% of control. Loin eye area was not increased (P greater than .05) in the pigs in Study 2; however, backfat thickness was reduced 16% by rpST (P less than .01). The effects of rpST were the same on both dietary regimens (P greater than .05). These studies demonstrate the effectiveness of rpST in increasing ADG and carcass leanness and improving FE in heavyweight pigs and in pigs fed alternative feedstuffs.     

Effect of salmon protein hydrolysate and spray-dried plasma protein on growth performance of weanling pigs

Two experiments, each consisting of 2 trials, were conducted to determine the effect of salmon protein hydrolysate (SPH) and spray-dried plasma protein (SDPP) fed during the first week postweaning and their subsequent effect on the growth performance of weanling pigs. Pigs were fed in a 3-phase feeding program with durations of 7 d for phase 1 in both Exp. 1 and 2; 14 or 15 d for phase 2 in Exp. 1 and 2, respectively; and 7 or 8 d for phase 3 in Exp. 1 and 2, respectively. Dietary treatments were fed only during phase 1, whereas the same diet was fed to all pigs in phases 2 and 3. Pigs were blocked by initial BW and sex, and littermates were balanced across treatments. Data from the 2 trials within each experiment were combined and analyzed together; no treatment × trial interactions (P > 0.10) were observed. In Exp. 1, a total of 324 weanling pigs (10 replications of 5 or 6 pigs per pen) with an average initial BW of 6.4 ± 1.3 kg were assigned to 1) a control diet with no SPH or SDPP, 2) 1.5% SPH, 3) 3.0% SPH, 4) 1.5% SDPP, 5) 3.0% SDPP, or 6) 1.5% SPH + 1.5% SDPP. Experiment 2 was similar to Exp. 1, but red blood cells were removed from all diets to reduce diet complexity. In Exp. 2, weanling pigs (n = 320, 14 replications of 5 or 6 pigs per pen) with an average initial BW of 5.4 ± 1.2 kg were assigned to 1) a control diet with no SPH or SDPP, 2) 1.5% SPH, 3) 1.5% SDPP, or 4) 1.5% SPH + 1.5% SDPP. Three batches of SPH were used, and each batch was analyzed for AA composition. In Exp. 1, the inclusion of SDPP or SPH during phase 1 did not affect (P > 0.10) ADG, ADFI, or G:F compared with those of pigs fed the control diet. No carryover effects on growth performance were observed in any of the subsequent phases. Overall, G:F was greater (P = 0.08) in pigs fed the 1.5% diets compared with those fed the 3.0% diets. In Exp. 2, no differences (P > 0.10) were observed in ADG, ADFI, or G:F among pigs fed the SPH or SDPP diets compared with those of pigs fed the control diet. Pigs fed the combined diet had greater (P < 0.10) overall ADFI compared with that of pigs fed the control diet, but ADFI was similar to that of pigs fed the SPH and SDPP diets. These results indicate that inclusion of up to 3% SDPP or SPH in diets fed during the first week postweaning did not affect the growth performance of weanling pigs, and no subsequent carryover effects were observed. Salmon protein hydrolysate did not affect the growth performance of weanling pigs and may be considered an alternative protein source in diets for weanling pigs.     

Effect of a high-fat diet on the performance response to porcine somatotropin (PST) in finishing pigs

One hundred sixty pigs were used in a 2 x 2 factorial design to compare the performance response to daily injection of porcine somatotropin (PST); (0 or 2 mg/d) in animals fed a 14% CP corn-soy diet (control, C) to those fed a diet with 10% added fat (F) and calorie:protein and lysine:protein ratios similar to that of the C diet. Treatments, assigned randomly to 20 pens (n = 5/treatment) of eight pigs each, were initiated at 90 kg body weight and continued for 28 d. Responses to PST and dietary fat were typical. These include improved gain and feed efficiency and decreased feed intake. The effects of dietary fat on intake and efficiency were accounted for largely by the difference in energy density of these diets. Across diets, PST treatment resulted in a 13% improvement in ADG (P less than .001), a 13% decrease in feed intake (P less than .0001) and a 22% improvement in efficiency (P less than .0001). Of particular interest were the additive (PST x diet interaction, P less than .2) effects of PST and dietary fat on gain in these animals. Pigs treated with PST that were fed the F diet had greater rates of gain than did PST-treated pigs fed the C diet (P less than .05). Treatment with PST increased ADG by 9% in pigs consuming the C diet vs 16% in pigs fed the F diet. Similarly, dietary fat resulted in 4 and 11% increases in ADG in pigs treated with 0 or 2 mg of PST/d.(ABSTRACT TRUNCATED AT 250 WORDS)     

Effect of diet and exercise on performance, carcass traits and plasma components of growing-finishing barrows

Twenty-four barrows (approximately 25 kg initial wt) were used in each of three 2 X 2 factorially arranged trials to study effects of exercise (not exercised vs walking 30 min/d, 6 d/wk on a treadmill) and diet (low energy vs high energy) on performance during the growing-finishing period. Average daily gain (ADG) of barrows not exercised was greater (P less than .07) than that of those exercised. Barrows fed the high-energy diet had greater (P less than .05) ADG, lower (P less than .01) feed intake and lower (P less than .01) feed-to-gain ratio than barrows fed low-energy diets. In trials 1 and 2, pigs were slaughtered when removed from test and selected carcass measurements and internal organ weights were obtained. Exercise did not significantly affect carcass length, backfat thickness, loin muscle area or lean cuts (as a percentage of off-test weight). Pigs fed the high-energy diet had more (P less than .01) backfat than those fed the low-energy diet. Neither the exercise program nor the diet had a significant effect on organ weights. Pigs not exercised had a higher (P less than .05) plasma albumin-to-globulin ratio and lower (P less than .05) plasma creatinine concentration than did pigs that were exercised. Also, pigs not exercised had slightly higher (P less than .08) plasma albumin and glucose, but lower (P less than .06) plasma globulin levels.(ABSTRACT TRUNCATED AT 250 WORDS)     

Growth performance of 20- to 50-kilogram pigs fed low-crude-protein diets supplemented with histidine, cystine, glycine, glutamic acid, or arginine

The purpose of this investigation was to compare the growth performance of grower pigs fed low-CP, corn-soybean meal (C-SBM) AA-supplemented diets with that of pigs fed a positive control (PC) C-SBM diet with no supplemental Lys. Five experiments were conducted with Yorkshire crossbred pigs, blocked by BW (average initial and final BW were 21 and 41 kg, respectively) and assigned within block to treatment. Each treatment was replicated 4 to 6 times with 4 or 5 pigs per replicate pen. Each experiment lasted 28 d and plasma urea N was determined at the start and end of each experiment. All diets were formulated to contain 0.83% standardized ileal digestible Lys. All the experiments contained PC and negative control (NC) diets. The PC diet contained 18% CP and was supplemented with only DL-Met. The NC diet contained 13% CP and was supplemented with L-Lys, DL-Met, L-Thr, and L-Trp. The NC + Ile + Val diet was supplemented with 0.10% Val + 0.06% Ile. The NC + Ile + Val diet was supplemented with either His (Exp. 1), Cys (Exp. 2), Gly (Exp. 2, 3, and 4), Glu (Exp. 3), Arg (Exp. 4), or combinations of Gly + Arg (Exp. 4 and 5) or Gly + Glu (Exp. 5). Treatment differences were considered significant at P < 0.10. In 3 of the 4 experiments that had PC and NC diets, pigs fed the NC diet had decreased ADG and G:F compared with pigs fed the PC diet. The supplementation of Ile + Val to the NC diet restored ADG in 4 out of 5 experiments. However, G:F was less than in pigs fed the PC diet in 1 experiment and was intermediate between the NC and PC diets in 3 experiments. Pigs fed supplemental Ile + Val + His had decreased G:F compared with pigs fed the PC. Pigs fed supplemental Cys to achieve 50:50 Met:Cys had decreased G:F compared with pigs fed the PC. Pigs fed Ile + Val + 0.224% supplemental Gly had similar ADG, greater ADFI, and decreased G:F compared with pigs fed the PC. Pigs fed Ile + Val + 0.52% supplemental Gly had ADG and G:F similar to that of pigs fed the PC. Pigs fed supplemental Glu had decreased G:F compared with pigs fed the PC. Pigs fed Ile + Val + 0.48% supplemental Arg had decreased G:F compared with pigs fed the PC. Pigs fed the diet supplemented with Gly + Arg had ADG and G:F similar to pigs fed the PC. Pigs fed the low-CP diets had reduced plasma urea N compared with pigs fed PC. The results of these experiments indicate that supplementing Gly or Gly + Arg to a low-CP C-SBM diet with 0.34% Lys, Met, Thr, Trp, Ile, and Val restores growth performance to be similar to that of pigs fed a PC diet with no Lys supplementation.