J. S. Radcliffe

Feeding conjugated linoleic acid partially recovers carcass quality in pigs fed dried corn distillers grains with solubles

Dried corn distillers grains with solubles (DDGS) fed to swine may adversely affect carcass quality due to the high concentration of unsaturated fat. Feeding CLA enhances pork quality when unsaturated fat is contained in the diet. The effects of CLA on growth and pork quality were evaluated in pigs fed DDGS. Diets containing 0, 20, or 40% DDGS were fed to pigs beginning 30 d before slaughter. At 10 d before slaughter, one-half of each DDGS treatment group was fed 0.6% CLA or 1% choice white grease. Carcass data, liver- and backfat-samples were collected at slaughter. Longissimus muscle area, 10th-rib back-fat depth, last rib midline backfat depth, LM color, marbling, firmness and drip loss, and bacon collagen content were not altered by DDGS or CLA. Outer layer backfat iodine values were increased (P <or= 0.05) with DDGS feeding and were 65.07, 69.75, and 74.25 for 0, 20, and 40% DDGS, respectively. Addition of CLA decreased (P <or= 0.05) outer layer backfat iodine values from 71.11 to 68.31. Diets containing DDGS decreased (P <or= 0.05) percent lean tissue contained in bacon from 48% for controls to 38% for pigs fed 40%. Abundance of fatty acid synthase, carnitine palmitoyl transferase Ia, acetyl-CoA-carboxylase, stearoyl-CoA desaturase, and glycerol-3-phosphate dehydrogenase mRNA in adipose or liver were not different (P > 0.05) for pigs fed DDGS. Feeding CLA decreased (P <or= 0.05) the Delta(9) de-saturase index in adipose tissue. The data indicate that decreased carcass firmness with DDGS feeding is not reflected by changes in lipogenic gene expression. Feeding 20% or more DDGS to finishing swine decreases bacon leanness, but inclusion of 0.6% CLA in the finishing diet can partially reverse these effects.

Controlling Salmonella infection in weanling pigs through water delivery of direct-fed microbials or organic acids. Part I: Effects on growth performance, microbial populations, and immune status1

Pigs (n = 88) weaned at 19 ± 2 d of age were used in a 14-d study to evaluate the effects of water-delivered direct-fed microbials (DFM) or organic acids on growth, immune status, Salmonella infection and shedding, and intestinal microbial populations after intranasal inoculation of Salmonella Typhimurium (10(10) cfu/pig). Pigs were challenged with Salmonella 6 d after commencement of water treatments. Treatments were 1) control diet; 2) control diet + DFM (Enterococcus faecium, Bacillus subtilis, and Bacillus licheniformis) in drinking water at 10(9) cfu/L for each strain of bacteria; 3) control diet + an organic acid-based blend (predominantly propionic, acetic, and benzoic acid) in drinking water at 2.58 mL/L; and 4) control diet + 55 mg/kg of carbadox. Serum samples were taken on d 6, 8, 10, and 14 for determination of tumor necrosis factor α (TNFα) concentrations. Fecal samples were taken on d 0, 5, 7, and 11 for determination of Salmonella shedding and enumeration of coliforms. Pigs were euthanized on d 6, 8, 10, and 14. Intestinal and cecal tissue and digesta and mesenteric lymph nodes were sampled and analyzed for Salmonella. Duodenal, jejunal, and ileal mucosal scrapings were sampled for measurement of mucosal TNFα concentrations. Water delivery of DFM prevented a decline in ADG on d 2 to 6 postchallenge compared with the negative control (P < 0.05). Coliform counts tended to be greater (P = 0.09) in the cecum of the DFM treatment group on d 2 postinfection compared with the negative control and acid treatment groups. However, Salmonella prevalence in the feces, gastrointestinal tract, or lymph nodes was not affected by water delivery of acids or DFM. Serum and mucosal TNFα concentrations were not affected by treatment throughout the study with the exception of ileal concentrations on d 4 postchallenge, which were greater in the negative control group compared with all other treatments (P < 0.05). The in-feed antibiotic was the only treatment that reduced Salmonella prevalence and this was localized to the cecum on d 8 postinfection. In conclusion, the DFM and organic acid treatments used in this study offered little or no benefits to pigs infected with Salmonella and should not be considered under the constraints of this study as viable alternatives to in-feed antibiotics in a pathogen challenge situation.

Effect of feeding reduced crude protein and phosphorus diets on weaning-finishing pig growth performance, carcass characteristics, and bone characteristics

Two experiments were conducted to determine the effects of feeding a corn- and soybean meal-based diet (control) or a low nutrient excretion (LNE) diet, formulated with reduced dietary CP and additional synthetic AA, low phytic acid corn, and phytase, on pig growth performance during the grower (BW=32 to 77 kg) and finisher (BW=78 to 126 kg) periods and on carcass and bone characteristics at slaughter. Pigs (32+/-1.3 kg of BW, Exp. 1; 6.7+/-0.27 kg of BW, Exp. 2) were blocked by sex and BW and randomly allotted to a control or LNE diet. Pigs were housed in 4 rooms during the nursery period and in 2 rooms during the grower and finisher periods, with individual and identical ventilation systems. Pigs were phase fed 3 nursery diets for 5 wk (Exp. 2) and phase fed 2 grower and 2 finisher diets for 16 wk (Exp. 1 and 2). Pigs were housed 4 or 5 pigs/pen with 9 pens x sex(-1) x treatment(-1) during the nursery period and 4 or 5 pigs/pen with 5 pens x sex(-1) x treatment(-1) in the grower phase and 2 or 3 pigs/pen in the finisher phase. Individual BW and pen feed disappearance were recorded weekly in the nursery period and every 2 wk in the grower-finisher period. Pigs were scanned ultrasonically at d 34 of the nursery period and wk 8 and 16 of the grower-finisher period to determine backfat depths and LM area. Ten pigs x sex(-1) x treatment(-1) were slaughtered at wk 16 of each experiment to determine carcass characteristics. Overall growth performance was not different during each experiment. However, nursery G:F (control=0.65; LNE=0.60), grower ADG (Exp. 1 and 2), and grower G:F (Exp. 2) were reduced (P<0.05) when the LNE diets were fed. Diet had no effect on 10th-rib carcass data in either experiment. Metatarsal bone ash percentage was reduced (P<0.05) when the LNE diets were consumed in both experiments. Feeding LNE diets resulted in the maintenance of overall growth performance, bone variables, and carcass characteristics. However, further refinements are still required in the nursery and grower phases of pig production to optimize LNE diet use by the swine industry.

Controlling Salmonella infection in weanling pigs through water delivery of direct-fed microbials or organic acids: Part II. Effects on intestinal histology and active nutrient transport1

The objective of this study was to evaluate the effects of water-delivered, direct-fed microbials (DFM) or organic acids on intestinal morphology and active nutrient absorption in weanling pigs after deliberate Salmonella infection. Pigs (n = 88) were weaned at 19 ± 2 d of age and assigned to 1 of the following treatments, which were administered for 14 d: 1) control diet; 2) control diet + DFM (Enterococcus faecium, Bacillus subtilis, and Bacillus licheniformis) in drinking water at 10(9) cfu/L for each strain of bacteria; 3) control diet + organic acid-based blend (predominantly propionic, acetic, and benzoic acids) in drinking water at 2.58 mL/L; and 4) control diet + 55 mg/kg carbadox. Pigs were challenged with 10(10) cfu Salmonella enterica var Typhimurium 6 d after commencement of treatments. Pigs (n = 22/d) were harvested before Salmonella challenge and on d 2, 4, and 8 after challenge. Duodenal, jejunal, and ileal mucosal tissues were sampled for measurement of villus height and crypt depth. Jejunal tissue was sampled for determination of active nutrient absorption in modified Ussing chambers. Duodenal villus height was greater in pigs fed in-feed antibiotic before infection (P < 0.05). Jejunal crypts were deeper in DFM- and acid-treated pigs on d 4 after infection compared with all other treatments (P < 0.05). Salmonella infection resulted in a linear decrease in phosphorus (P < 0.001) and glucose (P < 0.05) active transport, and an increase (P < 0.001) in glutamine uptake immediately after challenge. Salmonella infection reduced basal short-circuit current (I(sc)); however, water-delivered DFM or organic acid treatments caused greater basal I(sc) on d 2 after challenge than did carbadox. Carbachol-induced chloride ion secretion was greatest in negative control pigs before infection (P < 0.01) and DFM-treated pigs (P < 0.05) after infection. In conclusion, both the DFM and acidification treatments induced increases in basal active ion movement and jejunal crypt depth, which could be interpreted as responses consistent with increased Salmonella pathology, but none of the additives markedly affected intestinal absorptive and secretory function in response to Salmonella challenge.

Impact of Weaning Weight and Early Postweaning Growth of Pigs to Late Finishing Growth When Fed Either Corn- and Soybean Meal-Based Diets or Low Nutrient Excretion Nutrient-Dense Diets

ABSTRACT The BW growth of 1,385 barrows and gilts was evaluated from d-21 weaning to 130 kg BW. The pigs were assigned to a 2×2 factorial arrangement of treatments. The pigs were fed a series of either standard corn- and soybean meal-based control diets or low nutrient excretion nutrient-dense (LNE-ND) diets from 1 wk postweaning to 130 kg BW and assigned to rooms with either deep pit or pull plug-recharge manure storage treatments. The pigs were weighed at weaning, at 7 and 14 d postweaning, and at approximately 2-wk intervals from 28 d postweaning to a mean BW of 130 kg. Mixed model nonlinear equations including pig-specific random effects were evaluated for the generalized Michaelis-Menten function. The serial postweaning BW data were fitted to a mixed model generalized Michaelis-Menten equation. Relationships of weaning BW to late finishing BW and days to 125 kg BW were different for each dietary treatment. Late finishing BW and days to 125 kg BW had nonlinear relationships with weaning BW for pigs fed the LNE-ND diets and had linear relationships for pigs fed the control diets. The predicted changes in subsequent BW of the LNE-ND diets per kilogram of change in weaning BW were greater for pigs with the lightest weaning BW than for pigs with average to above-average weaning BW. Across both dietary treatments, pigs with greater weaning BW and greater early postweaning ADG required fewer days to achieve target market BW.

Effects of porcine reproductive and respiratory syndrome virus on pig growth, diet utilization efficiency, and gas release from stored manure

The objectives of this study were to examine the effects of porcine reproductive and respiratory syndrome virus (PRRSV) infection and vaccination on pig growth, dietary nutrient efficiency of utilization, manure output, and emissions of CO, CH, HS, NO, and NH gases from stored manure. Forty-eight pigs, aged 21 d at the start of the study, were subjected to 1 of 4 treatment combinations arranged in a 2 × 2 factorial design with main factors of PRRSV vaccination and PRRSV infection. Body weight, ADFI, manure output, and nutrient efficiency of utilization were assessed and gas emissions from stored manure were determined daily from 50 to 78 d of age and for 24 d after completion of the animal phase. Infection with PRRSV markedly reduced final BW, ADG, and ADFI ( < 0.01) and reduced efficiencies of ADF and ether extract utilization ( = 0.05 and = 0.02, respectively) regardless of vaccination status. No significant treatment effects were found on manure output, manure pH, efficiencies of lignin utilization, and N retention. Infecting pigs with PRRSV increased daily manure CO emission per pig ( = 0.01). There was an interaction between immunization and infection for NO per pig with manure from uninfected, vaccinated pigs producing as much as the manure from infected, vaccinated pigs whereas there was a difference by PRRSV infection state for nonvaccinated pigs. There were also interactions between treatments for HS and NO emissions per kilogram of manure volatile solids excreted ( = 0.01 and = 0.0001, respectively) with the same pattern as for NO per pig; that is, the vaccinated pigs had similar rates of emission regardless of infection state. Pigs infected with PRRSV increased NO nitrogen per kilogram of total N excreted compared with noninfected groups ( = 0.03). Collectively, these results indicated that PRRSV infection caused decreased growth rates and nutrient utilization efficiency and increased gas emissions from stored manure.

Assessment of Hull-less Barley as a Locally Grown Swine Feed Ingredient in the Mid-Atlantic Region of the United States1

Abstract Crossbred pigs (six replicate pens of four pigs per treatment, avg. initial BW = 38 kg) were used in a 6-wk growth and digestibility trial to assess a hull-less barley adapted for the mid Atlantic region of the U.S. as the primary ingredient in pelleted diets for growing pigs. There were five experimental diets: 1) a corn-soybean meal-based diet, 2) a diet containing 46% hull-less barley and 1.6% added fat, 3) a diet containing 41% hulled barley and 4.1% added fat, 4) a diet containing 46% hulled barley and 1.6% added fat, and 5) a diet containing 46% wheat and 0.68% added fat. For diets based on small grains, a fixed inclusion rate of 25% corn was used. With the exception of Diet 4, all diets were formulated to be iso-lysinic and iso-caloric. Diet type had no effect (P>0.10) on ADFI or ADG. Pigs fed the hulled barley, high-fat diet (Diet 3) had slightly improved feed efficiency (P

Effects of dirty housing and a Typhimurium DT104 challenge on pig growth performance, diet utilization efficiency, and gas emissions from stored manure

The objectives of this study were to elucidate the effects of a dirty environment and a challenge plus associated environmental contamination on pig growth performance, diet utilization efficiency, and gas emissions (CO, NH, CH, NO, and HS) from stored manure. Twenty-four weaned barrows, aged 31 d at initiation of the trial, were randomly allotted to 3 different treatments in a completely randomized design. Treatments were: pigs housed in cages with manure removed and cages washed daily (Clean); pigs housed in cages sprayed daily with manure slurry mixtures (Dirty); or pigs challenged with Typhimurium DT104 and housed in cages that were not washed, but manure was removed daily ( challenge). Rectal temperature, body weight, daily feed intake, manure output, manure composition, and gas emissions from stored manure were measured throughout the 24-d animal phase. The Dirty and challenge treatments were statistically compared to the Clean treatment to evaluate individual effects. Dirty housing tended to decrease ADG from d 1 to 24 ( = 0.06) but there were no other effects on pig performance compared with the Clean treatment. In contrast, a challenge was associated with a marked reduction in each of the measured indicators of pig performance. challenge increased the carbon to nitrogen ratio, ether extract, and lignin concentrations in excreted manure ( = 0.02, 0.01, 0.003, respectively), and increased manure and head space temperatures in manure tanks ( < 0.0001). Gas emissions from stored manure of pigs on the Dirty or treatments were increased for each of the measured gases as compared to the Clean treatment ( < 0.01) when expressed per unit of BW gain. When gas emissions from manure of pigs housed in the Dirty treatment were expressed per unit of manure volatile solids (VS), they were increased for NH, CH, and HS ( < 0.02). challenge was associated with increased emissions of CO, and NO and decreased emissions of HS per kilogram manure VS compared to the Clean treatment ( = 0.06, 0.03, 0.04, respectively). Collectively, these results indicated that a challenge and associated housing contamination caused depressed growth rate and increased manure gas emissions, while exposure to a Dirty environment slightly reduced growth performance and clearly increased manure gas emissions per unit of BW gain as compared to Clean control.

Effects of Feeding Restaurant Grease With or Without Conjugated Linoleic Acid or Phase-Integrated Beef Tallow on Finishing Pig Growth Characteristics and Carcass Fat Quality

Abstract The objective of this study was to determine the effect of conjugated linoleic acid (CLA) and tallow on belly firmness in 120 gilt finishing pigs. Pigs were assigned to 1 of 5 treatment combinations and fed 30 d prior to slaughter. Treatments were as follows: control, a 5% restaurant grease for 30 d (RG30); 5% restaurant grease for 0 to 20 d and switched to CLA (0.83%) and restaurant grease (4.17%) combination for 20 to 30 d (RGCLA); 5% restaurant grease for 0 to 20 d and switched to a 5% tallow for 20 to 30 d (Tallow10); 5% restaurant grease for 0 to 10 d and switched to a 5% tallow for final 20 d (Tallow20); and 5% tallow for 0 to 30 d (Tallow30). No changes occurred in drip loss, pH, loin eye color, or size, and no difference occurred in growth parameters, except for ADG between 20 to 29 d, where pigs allotted to Tallow20 and Tallow30 had greater (P

Dietary Phosphorus Removal with and without Microbial Phytase Addition for Growing Finishing Pigs1

One hundred seventy one crossbred pigs (53.3 ± 1.4 kg) were used to evaluate the effects of removing inorganic P from finishing diets with or without phytase addition during two 28-d finisher phases (EARLY and LATE, respectively). Dietary treatments were: 1) control (Trt 1; EARLY 0.49% total P, 0.19% available P (aP); LATE 0.43% total P, 0.15% aP); 2) Trt 1 without inorganic P (Trt 2; EARLY= 0.36% total P, 0.07% aP; LATE= 0.33% total P, 0.06% aP); and 3) Trt 2 + 500 FTU/kg phytase (Trt 3). Average daily gain, ADFI and G:F (g/kg) were calculated every 2 wk. Pigs were scanned for 10th rib fat thickness (FT) and longissimus area (LEA) and values were adjusted to a common BW (104 kg). One male and one female per pen were slaughtered and fourth metacarpal bones collected and ashed. During the EARLY and LATE phases pigs fed Trt 2 had lower ADG and ADFI (P≤0.05; 760 vs. 831 and 2275 vs. 2399 g, respectively) than pigs fed Trt 3. Adjusted FT and LEA did not differ among treatments. Fourth metacarpal dry and ash weights were greater for pigs fed Trt 3 (P<0.05) as compared to pigs fed Trt 2. Bone ash percentage did not differ between these treatments, however pigs fed Trt 1 had greater bone ash percentage (P<0.05) than pigs fed diets lacking inorganic P (Trt 1 vs. 2,3). Removing inorganic P reduces ADG and ADFI, however, addition of phytase restores animal performance.