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

Performance response of increasing the standardized ileal digestible tryptophan:lysine ratio in diets containing 40% dried distiller grains with solubles

A total of 1,170 pigs (PIC 800 × PIC, initially 38.6 kg) were used in a 98-d grow-finish study to determine the performance response of pigs fed increasing levels standardized ileal digestible (SID) Trp:Lys ratio in diets containing 40% dried distillers grains with solubles (DDGS). Five dietary treatments were fed and consisted of a corn-soybean meal (SBM) diet or diets containing 40% DDGS with SID Trp:Lys ratios of 15%, 18%, 21%, or 24%. Each treatment was replicated 9 times and pens contained 26 pigs with the equal number of gilts and barrows. Data was analyzed as a randomized complete block design with previous nursery treatment as a random blocking factor. Pair-wise comparisons were used to evaluate the impact of diets on performance and carcass traits; specifically to compare the corn-SBM dietary treatment against other dietary treatments. Single degree of freedom orthogonal polynomials were used to evaluate the dose-response of increasing the SID Trp:Lys ratio in 40% DDGS diets. Increasing the SID Trp:Lys ratio in diets containing 40% DDGS increased (linear, P ≤ 0.02) average daily gain (ADG), average daily feed intake (ADFI), final body weight (BW), hot carcass weight (HCW), carcass gain, and daily carcass gain. Increasing the SID Trp:Lys ratio in 40% DDGS diets did not impact (P ≥ 0.65) gain to feed (G:F) for the cumulative period. Pigs fed the corn-SBM diet had greater (P ≤ 0.01) ADG and a heavier (P ≤ 0.01) final BW compared to pigs fed 40% DDGS diets, regardless of the SID Trp:Lys ratio. Diets that contained 40% DDGS with a SID Trp:Lys ratio of 24% had no difference (P|t| = 0.25) in ADFI compared to the corn-SBM dietary treatment. The cumulative G:F of pigs did not differ (P = 0.32) between pigs fed corn-SBM diets and diets containing 40% DDGS regardless of the SID Trp:Lys ratio. However, pigs receiving the corn-SBM diets had heavier HCW, greater carcass yields, total carcass gain, and daily carcass gain (P < 0.01) compared to pigs fed the 40% DDGS diets regardless of SID Trp:Lys ratio. In conclusion, increasing the SID Trp:Lys ratio in 40% DDGS diets improved ADG and ADFI for the overall grow-finish period. However, when compared to a corn-SBM diet, increasing the SID Trp:Lys ratio in 40% DDGS diets did not correct the growth performance or carcass characteristics of pigs.

Impact of increasing standardized ileal digestible valine: lysine in diets containing 30% dried distiller grains with solubles on growing pig performance

A total of 2,430 pigs (DNA 600 × Topigs Norsvin 70, initially 39.4 kg) were used in a 28-d trial to determine the standardized ileal digestible (SID) Val:Lys requirement for pigs fed with diets containing 30% DDGS. Treatments included five diets containing 30% DDGS with SID Val:Lys ratios of 60%, 65%, 70%, 75%, and 80%, plus a corn soybean meal (SBM) diet, for a total of six dietary treatments. Diets were formulated to be isocaloric through the inclusion of fat and to contain equal amounts of SID Lys within phase. Pens were assigned to dietary treatment in a randomized complete block design with initial body weight (BW) as the random blocking factor. Each dietary treatment was replicated 15 times and pens contained 27 pigs, balanced for sex. Increasing the SID Val:Lys ratio in diets containing 30% DDGS increased (Quadratic; P ≤ 0.007) 14-d BW, final BW, average daily gain (ADG), average daily feed intake (ADFI), and gain:feed (G:F) for all periods. Providing an SID Val:Lys ratio of 75% resulted in the heaviest 14-d BW and final BW as well as greater ADG and ADFI of pigs fed with 30% DDGS for all periods. The G:F response was maximized when an SID Val:Lys ratio of 70% was provided from day 0 to 14 while an SID Val:Lys ratio of 75% maximized G:F from day 14 to 28 and for the cumulative period. The SID Val:Lys requirement was estimated at 66.6% (95% CI [65.9, 67.4]), 65.7 (95% CI: [64.8, 66.5]), and 68.4% (95% CI [66.0, 70.8]) for ADG, ADFI, and G:F, respectively, using the straight broken line (SBL) method and 69.9% (95% CI [68.2, 71.5]), 67.6 (95% CI [65.4, 69.8]), and 72.8% (95% CI [69.8, 75.8]) for the quadratic broken line (QBL) method. Pigs fed the corn-SBM diet had heavier 14-d BW, final BW, and greater ADG, ADFI, G:F (P ≤ 0.032) compared to pigs fed diets containing 30% DDGS, except for cumulative ADFI compared to pigs receiving 75% SID Val:Lys (P = 0.167). In conclusion, these results suggest that when feeding 30% DDGS during the growing period, an SID Val:Lys ratio of 68% would yield more than 99% and 97% of the maximum ADG and G:F response for the 39 to 68 kg pigs. However, growth performance of pigs fed diets containing 30% DDGS did not equate to pigs consuming the corn-SBM diet regardless of the SID Val:Lys ratio.

Effects of feeding variable levels of mycotoxins with or without a mitigation strategy on growth performance, gut permeability, and oxidative biomarkers in nursery pigs

The objectives were to determine how high levels (&gt; 2.5 mg/kg diet) of deoxynivalenol (DON), in conjunction with other naturally occurring mycotoxins (MTX) would impact growth, intestinal integrity, and oxidative status, with or without a mitigation strategy, in nursery pigs. One-hundred and five pigs (5.5 ± 0.52 kg) were randomly allotted to 35 pens and fed dietary treatments for 45 d. Treatments were factorially arranged with the inclusion of MTX being low (L-MTX; &lt; 1 mg/kg diet) or high (H-MTX; &gt; 2.5 mg/kg diet) in combination with no mitigation strategy or the inclusion of a mitigation strategy (Biofix® Plus, BPL; 1.5 mg/kg diet). There was no interaction between MTX level and BPL inclusion on average daily gain (ADG) or gain to feed ratio (GF), (P &gt; 0.10). Compared to pigs fed diets containing L-MTX, feeding pigs diets containing H-MTX decreased ADG and GF (P &lt; 0.05). The addition of BPL had no effect on ADG (P &gt; 0.10), but improved GF (P = 0.09). There was an interaction between MTX and BPL on average daily feed intake (ADFI), where the addition of BPL had no effect on ADFI of pigs fed L-MTX diets but improved ADFI of pigs fed H-MTX diets (P = 0.09). An interaction was detected between MTX and BPL on protein oxidation as measured by plasma protein carbonyls (PC, P = 0.01), where the inclusion of BPL decreased plasma PC in pigs fed H-MTX diets to a greater extent than pigs fed the L-MTX diets. There was no interaction between MTX and BPL, or an effect of MTX or BPL on DNA damage as measured by 8-hydroxy-2ʹdexoxyguanosine (P &gt; 0.10). There was no interaction between MTX and BPL, or a BPL effect on lipid damage as measured by thiobarbituic acid reactive substances (TBARS, P &gt; 0.10), but pigs fed diets containing H-MTX exhibited lower concentrations of plasma TBARS (P = 0.07) compared to pigs fed L-MTX diets. There was no interaction between MTX and BPL, or an effect of MTX or BPL on plasma lactulose and mannitol ratio as a measure of intestinal permeability (P &gt; 0.10). In conclusion, feeding H-MTX decreased ADG and GF, decreased plasma TBARS, but did not affect plasma 8-hydroxy-2ʹdexoxyguanosine or plasma LM ratio. The inclusion of a mitigation strategy improved ADFI when pigs were fed H-MTX diets and improved GF regardless of MTX level. Addition of a mitigation strategy also reduced plasma protein damage but did not affect indicators of DNA or lipid damage or affect gastrointestinal integrity.

Evaluation of dietary mycotoxin control strategies on nursery pig growth performance and blood measures

A total of 4,318 pigs (337 × 1,050, PIC; initially 6.5 ± 0.08 kg) were used in a 35-day study to evaluate dietary mycotoxin control strategies on nursery pig performance and blood measures. Pigs were weaned at approximately 21 d of age and randomly allotted to 1 of 5 dietary treatments in a randomized complete block design with blocking structure including sow farm origin, date of entry into facility, and average pen BW. A total of 160 pens were used with 80 double-sided 5-hole stainless steel fence line feeders, with feeder serving as the experimental unit. For each feeder, 1 pen contained 27 gilts and 1 pen contained 27 barrows. There were 16 replications per dietary treatment. A common phase 1 diet was fed to all pigs in pelleted form for 7 day prior to treatment diets. Experimental treatments were fed from days 7 to 42 after weaning (days 0 to 35 of the study) and included a low deoxynivalenol (DON) diet (1.12 ± 0.623 mg/kg), high DON diet (2.34 ± 1.809 mg/kg), high DON+ 0.50% sodium metabisulfite (SMB), high DON+ one of two mitigating products; 0.30% Technology1, or 0.30% Technology1+. Technology1 and 1+ are comprised of clays, yeast cell wall components, and a blend of plant extracts. Technology1+ also contains SMB. Overall (days 0 to 35), pigs fed high DON had decreased (P < 0.05) final BW, ADG, and ADFI compared with low DON. Additionally, pigs fed high DON+SMB had increased (P < 0.05) ADG compared with all other treatments. An improvement (P < 0.05) in G:F was observed in pigs fed high DON + SMB or high DON + Technology1+ compared with the low DON or high DON + Technology1 diets with high DON diets intermediate. Pigs fed high DON + SMB or high DON + Technology1 diets had reduced (P < 0.05) total removals and mortality compared with pigs fed low DON diets with high DON and high DON + Technology1+ intermediate. Liquid chromatography/mass spectrometry analysis of circulating blood collected on day 35 revealed that pigs fed high DON or high DON + Technology1 had increased (P < 0.05) DON concentrations compared to low DON with high DON + SMB and high DON + Technology1+ intermediate. In summary, pigs fed high DON diets had reduced performance compared with pigs fed low DON. Sodium metabisulfite in high DON diets provided a benefit in growth performance with ADG and G:F exceeding growth performance in the low DON diet while, the improved G:F ratio combined with other immunometabolic changes (gamma glutamyltransferase and creatine kinase) associated with Technology1+ warrant further investigation.

Comparative efficacy of commercially available deoxynivalenol detoxifying feed additives on growth performance, total tract digestibility of components, and physiological responses in nursery pigs fed diets formulated with naturally contaminated corn

Comparative efficacy of deoxynivalenol (DON) detoxifying feed additives (FA) was evaluated in growth performance (exp. 1) and apparent total tract digestibility (ATTD; exp. 2) nursery pig studies. Six corn-soybean meal-based diets were used: 1) positive control (PC, formulated with <1.5 ppm DON corn), negative control (NC, formulated with 5.5 ppm DON corn), NC + FA1 (clay plus yeast cell wall extract), NC + FA2 (aluminosilicate), NC + FA3 (aluminosilicate plus fungal extract), and NC + FA4 (sodium metabisulfite, SMB). In exp. 1, 144 pigs (body weight [BW], 10.2 ± 0.1kg) were housed (4 pigs/pen), allocated to diets (n = 6) based on BW, and fed for 4-wk. The BW and feed intake were monitored weekly. On d 7, one pig/pen was bled for plasma and euthanized for organ weight and tissue samples. Assayed DON concentration in PC, NC, NC + FA4 was 0.29, 2.86, and 1.21 ppm, respectively. In wk-1, the average daily gain (ADG) of pigs fed NC + FA4 was not different (P > 0.05) to that of pigs fed PC diet but greater (P = 0.01) than for pigs fed NC without or with other FA. Pigs fed NC and NC + FA2 had lower (P = 0.026) average daily feed intake (ADFI) than pigs fed PC and NC + FA3. Pigs fed NC + FA4 had greater (P = 0.003) G:F than pigs fed the other diets. Diets had no effect (P > 0.05) on ADG, ADFI, and G: F after first week, plasma concentration of urea and creatinine or liver and spleen weight. Pigs fed NC diets had greater (P = 0.01) jejunal mRNA expression of superoxide dismutase 1 relative to pigs fed PC or NC plus FA. Jejunal histomorphology and mRNA expression of nutrient transporters, inflammatory cytokines, and tight junction proteins and ceca digesta concentration of short-chain fatty acids were not affected (P > 0.05) by the diet. In exp. 2, 24 barrows (BW 10.2 ± 0.3 kg) were individually placed in metabolism crates and allocated to four diets: PC, NC, NC + FA3, and NC + FA4 (n = 6) containing TiO₂ as digestibility marker. Pigs were adjusted to diets for 5 d, followed by a 2-d grab fecal sample collection. Pigs fed PC and NC + FA4 diets had higher ATTD of dry matter, gross energy, and crude protein than NC fed pigs. The FA3 was intermediate in digestibility response. In conclusion, FA containing sequestering component plus fungal extract or SMB in DON-contaminated feed resulted in commensurate nursery pig performance to PC. The tested FA mitigated intestinal oxidative stress through decreased expression of genes for superoxide dismutase.

Intestinal Health of Pigs Upon Weaning: Challenges and Nutritional Intervention

The primary goal of nursery pig management is making a smooth weaning transition to minimize weaning associated depressed growth and diseases. Weaning causes morphological and functional changes of the small intestine of pigs, where most of the nutrients are being digested and absorbed. While various stressors induce post-weaning growth depression, the abrupt change from milk to solid feed is one of the most apparent challenges to pigs. Feeding functional feed additives may be viable solutions to promote the growth of nursery pigs by enhancing nutrient digestion, intestinal morphology, immune status, and by restoring intestinal balance. The aim of this review was to provide available scientific information on the roles of functional feed additives in enhancing intestinal health and growth during nursery phase. Among many potential functional feed additives, the palatability of the ingredient and the optimum supplemental level are varied, and these should be considered when applying into nursery pig diets. Considering different stressors pigs deal with in the post-weaning period, research on nutritional intervention using a single feed additive or a combination of different additives that can enhance feed intake, increase weight gain, and reduce mortality and morbidity are needed to provide viable solutions for pig producers. Further research in relation to the feed palatability, supplemental level, as well as interactions between different ingredients are needed.

Zearalenone Mycotoxicosis: Pathophysiology and Immunotoxicity

Mycotoxicosis refers to the deleterious pathological effects of different types of toxins produced by some worldwide distributing fungi. Mycotoxins, as secondary metabolites are affecting different organs and systems both in animals and human beings. Zearalenone (ZEA), the well-known estrogenic mycotoxins, is an immunotoxic agent. This macrocyclic beta-resorcyclic acid lactone is mycotoxin procreated as a secondary metabolic byproduct by several types of Fusarium, encompassing Fusarium roseum, Fusarium culmorum, Fusarium graminearum, and different other types. Attributing to its potent estrogenic activity, ZEA has been incriminated as one of the major causes of female reproductive disorders. Thus, the purpose of the present review article is to appraise the pathophysiological consequences and subsequent explore the progress in the research field of zearalenone immunotoxicities.

Effects of feeding high-protein corn distillers dried grains and a mycotoxin mitigation additive on growth performance, carcass characteristics, and pork fat quality of growing-finishing pigs

Two experiments investigated the effects of feeding diets containing 30% of novel high-protein distillers dried grains (HP-DDG) sources to growing–finishing pigs on growth performance, carcass characteristics, and pork fat quality. A four-phase feeding program was used in both experiments, and diets within phases were formulated based on National Research Council (NRC; 2012) recommendations for metabolizable energy and standardized ileal digestible amino acid content of HP-DDG. In Exp. 1, a total of 144 pigs (body weight [BW] = 20.3 ± 1.6 kg) were fed either corn-soybean meal control diets (CON) or 30% HP-DDG diets (HP-DDG) containing 0.7 mg/kg deoxynivalenol (DON), 0.1 mg/kg fumonisins (FUM), and 56 μg/kg zearalenone (ZEA) for 8 wk. On week 9, a mycotoxin mitigation additive (MA) was added to CON and HP-DDG diets, resulting in a 2 × 2 factorial arrangement of treatments consisting of: CON, CON + MA, HP-DDG, and HP-DDG + MA. Pigs fed HP-DDG had lower (P < 0.01) average daily gain (ADG) and average daily feed intake (ADFI) compared with those fed CON during the first 8 wk. After MA was added to diets, pigs fed HP-DDG diets without MA had lower (P < 0.05) overall ADG than those fed HP-DDG + MA and less (P < 0.05) final BW than pigs fed CON or CON + MA. Adding MA to HP-DDG diets containing relatively low concentrations of mycotoxins was effective in restoring growth performance comparable to feeding CON. In Exp. 2, a different source of HP-DDG was used, and mycotoxin MAs were added to all diets at the beginning of the trial. A total of 144 pigs (BW = 22.7 ± 2.3 kg) were fed either a corn-soybean meal control diet or a 30% HP-DDG diet containing 0.5 mg/kg DON and 0.8 mg/kg FUM for 16 wk. Pigs fed HP-DDG diets had less (P < 0.01) final BW and ADG than pigs fed CON, but there were no differences in ADFI. Feeding the HP-DDG diets reduced (P < 0.01) hot carcass weight, carcass yield, longissimus muscle area (LMA), and percentage of carcass fat-free lean compared with pigs fed CON but did not affect backfat (BF) depth. Pigs fed HP-DDG had less (P < 0.01) saturated fatty acid (SFA) and monounsaturated fatty acid (MUFA) content and greater (P < 0.01) polyunsaturated fatty acid (PUFA) and iodine value in BF than pigs fed CON. These results suggest that feeding diets containing relatively low concentrations of co-occurring mycotoxins can be detrimental to growth performance, and the addition of MA alleviated the growth reduction. Feeding 30% HP-DDG reduced BW, ADG, carcass yield, LMA, and percentage of fat-free lean of growing–finishing pigs but yielded acceptable pork fat quality.

The Evaluation of the Antioxidant and Intestinal Protective Effects of Baicalin-Copper in Deoxynivalenol-Challenged Piglets

The present study was performed to evaluate the antioxidant and intestinal protective effects of baicalin-copper on deoxynivalenol-challenged piglets. Forty weaned piglets were randomly divided into four groups and assigned to different diets: (1) basal diet (Con), (2) 4 mg/kg deoxynivalenol of basal diet (DON), (3) 5 g/kg baicalin-copper of basal diet (BCU); and (4) 4 mg/kg deoxynivalenol + 5 g/kg baicalin‐copper of basal diet (DBCU). The results showed that the ADFI and ADG of piglets in the DON group were markedly lower than those in the Con group, but the ADFI and ADG of the DBCU group were not significantly different from those of the Con group. In piglets fed a DON-contaminated diet, dietary supplementation with BCU significantly decreased the mRNA levels of P70S6K, 4E-BP1, and HSP70 in the liver, the protein expression of HO-1 in the jejunum, and the expression of p-Nrf2 and p-NF-κB in the ileum but increased Mn-SOD activity in serum. Dietary supplementation with BCU increased jejunal maltase, ZIP4 and MT mRNA levels, and serum concentrations of Arg, Val, Ile, Leu, Lys, and Tyr in DON-contaminated piglets. In summary, BCU can alleviate the growth impairment induced by DON and enhance antioxidant capacity and nutrition absorption in piglets fed DON-contaminated diets.

Effects of deoxynivalenol and sodium meta-bisulphite on nutrient digestibility in growing pigs

Deoxynivalenol (DON), a mycotoxin synthesised by the Fusarium, is known to affect the growth of pigs. This effect can be attenuated with sodium meta-bisulphite (SBS). The aim of this study was to evaluate the effect of SBS with antioxidant blend on nutrient digestibility in pigs fed a diet contaminated naturally with DON. Six crossbred castrated pigs fitted surgically with single-T cannulas in the distal ileum received one of four barley-corn-soybean diets with or without SBS. After 8 d of feeding, faeces and ileal digesta were collected for 2 d. Apparent ileal digestibility (AID) of the dry matter (DM), energy, nutrients and DON, and apparent total tract digestibility (ATTD) of DM, acid detergent fibre (ADF), neutral detergent fibre (NDF), energy and DON were evaluated. The AID of phosphorus, calcium and some amino acids was increased (p < 0.05) in the DON diets whereas the ATTD of DM and energy tended to decrease (p = 0.064 and p = 0.071). SBS reduced the AID of DM, energy, ADF, ether extract, phosphorus and DON (p < 0.05) but had no effect on the ATTD of DM, energy, fibre or DON. These results show that DON improved the AID of some nutrients but tended to reduce the ATTD of energy, which could explain, although anorexia is the main effect of DON on live weight gain, the reported negative effect of DON on pig growth. Finally, SBS with antioxidant blend had reduced AID of some nutrients and intestinal absorption of DON.

Effects of sodium metabisulfite additives on nursery pig growth

Sodium metabisulfite (SMB)-based feed additive efficacy was evaluated in three nursery pig growth experiments where pigs were fed diets containing low deoxynivalenol (<1.5 mg/kg; DON) concentrations. Pigs were weaned at approximately 22 d of age and randomly allotted to pens with one pen of 27 gilts and one pen of 27 barrows per feeder; thus, feeder was the experimental unit. In experiment 1, a total of 2,268 pigs were used in a 35-d trial with 21 feeders per treatment. Experimental treatments included a control diet or the control with 0.50% SMB-based Product 1 (Defusion; Provimi, Brookville, OH) fed in phase 1 and 0.25% fed in phases 2 and 3, then all pigs were fed a control diet for the last week of the study. Pigs fed Product 1 had greater (P < 0.05) ADG, ADFI, and G:F compared with pigs fed the control diet from days 0 to 28. However, from days 28 to 35, the opposite response was observed with pigs fed the control diet having greater ADG and G:F than pigs previously fed Product 1. Despite this response, pigs fed Product 1 were heavier (P < 0.05) on day 35 than control-fed pigs. In experiment 2, a total of 4,320 pigs were used in a 42-d trial. Pigs were fed a control diet or diets with SMB-based either Product 1 or Product 2 (NutriQuest, Mason City, IA) at different concentrations and durations. Among the various treatments, Product 1 or Product 2 concentrations ranged from 0.50% initially to 0.25%, 0.15%, or none the last week of the study. Overall, pigs fed either of the additives at the highest concentrations and for the longest period of time had greater (P < 0.05) ADG and ADFI compared with pigs fed the control diet, with those fed lower concentrations or shorter durations being intermediate. In experiment 3, a total of 2,808 pigs were used in a 28-d trial with 13 feeders per treatment. All pigs were fed a common diet for 7 d after weaning. Pigs were then fed either a control diet (without any SMB-containing product) or a diet containing Product 1 (0.50% and 0.25% from days 0 to 21 and 21 to 28, respectively) or SMB (0.50% and 0.25% from days 0 to 21 and 21 to 28, respectively) or 0.25% SMB from days 0 to 28. Overall, pigs fed Product 1 or high-SMB diets had greater (P < 0.05) ADG compared with pigs fed low-SMB or control diets. In conclusion, results of these experiments indicate that in diets with low DON concentrations, these SMB-based products increased ADG compared with control diets.

The progression of deoxynivalenol-induced growth suppression in nursery pigs and the potential of an algae-modified montmorillonite clay to mitigate these effects

Two experiments were conducted to characterize the progression of deoxynivalenol (DON)-induced growth suppression and to investigate algae-modified montmorillonite clay (AMMC) as a means to alleviate the effects of DON in nursery pigs. In both experiments, naturally DON-contaminated wheat was used to produce diets with desired DON levels. In Exp. 1, 280 barrows and gilts (10.0 ± 0.2 kg BW) were used in a 28-d experiment arranged in a 2 × 2 + 1 factorial design with 8 replicates per treatment. The 5 treatments consisted of 2 positive control (PC) diets with DON below detection limits and with or without 0 or 0.50% AMMC and 3 negative control (NC) diets with 5 mg/kg of DON and containing 0, 0.25, or 0.50% AMMC. No DON × AMMC interactions were observed. Overall, pigs fed DON had decreased ( < 0.001) ADG and final BW regardless of AMMC addition. Feeding DON-contaminated diets elicited the most severe depression ( < 0.001) in ADFI and G:F from d 0 to 3, remaining poorer overall ( < 0.01) but lessening in severity as exposure time increased. Pigs fed DON diets had greater ( < 0.05) within pen BW variation (CV) on d 28. Although the addition of 0.50% AMMC to diets restored ( < 0.05) ADFI from d 14 to 21 to levels similar to the PC, no other differences were observed for AMMC inclusion. In Exp. 2, 360 barrows (11.4 ± 0.2 kg BW) were used in a 21-d experiment with 9 dietary treatments arranged in a 3 × 3 factorial design with DON and AMMC inclusion as main effects. There were 8 replicate pens per treatment. Treatments consisted of 3 PC diets without DON, 3 low-DON (1.5 mg/kg DON) NC diets, and 3 high-DON (3 mg/kg DON) NC diets with 0, 0.17, or 0.50% AMMC incorporated at each DON level. No DON × AMMC interactions were observed. As DON level increased, ADG and final BW decreased (quadratic, < 0.05), driven by decreased (quadratic, < 0.01) ADFI and poorer (quadratic; < 0.05) G:F. At both 1.5 and 3 mg/kg DON, reductions in ADG were most marked from d 0 to 7 (15 to 22% lower) and were least distinct from d 14 to 21 (5 to 6% lower). Incorporating AMMC at increasing levels had no effect on ADG, ADFI, G:F, or final BW. Overall, these experiments reinforce DON effects on feed intake but also indicate that the effects of DON on G:F may be more severe than previously thought. Furthermore, some pigs appear to develop tolerance to DON, as effects on ADFI and G:F lessen over time. However, the addition of AMMC did not offset the deleterious effects of DON.

Effects of potential detoxifying agents on growth performance and deoxynivalenol (DON) urinary balance characteristics of nursery pigs fed DON-contaminated wheat

Two experiments were conducted to evaluate potential detoxifying agents on growth of nursery pigs fed deoxynivalenol (DON)-contaminated diets. Naturally DON-contaminated wheat (6 mg/kg) was used to achieve desired DON levels. In a 21-d study, 238 pigs (13.4 ± 1.8 kg BW) were used in a completely randomized design with a 2 × 2 + 1 factorial arrangement. Diets were: 1) Positive control (PC; < 0.5 mg/kg DON), 2) PC + 1.0% Product V (Nutriquest LLC, Mason City, IA), 3) Negative control (NC; 4.0 mg/kg DON), 4) NC + 1.0% Product V, and 5) NC + 1.0% sodium metabisulfite (SMB; Samirian Chemicals, Campbell, CA). There were 6 or 7 replicate pens/treatment and 7 pigs/pen. Analyzed DON was decreased by 92% when pelleted with SMB, but otherwise matched formulated levels. Overall, a DON × Product V interaction was observed for ADG ( 0.05) with a tendency for an interaction for ADFI ( 0.10). As anticipated, DON reduced ( 0.001) ADG and ADFI, but the interaction was driven by even poorer growth when Product V was added to NC diets. Pigs fed NC diets had 10% poorer G:F ( 0.001) than PC-fed pigs. Reductions in ADG due to DON were most distinct (50%) during the initial period. Adding SMB to NC diets improved ( 0.01) ADG, ADFI, and G:F, and improved ( 0.02) ADG and G:F compared to the PC diet. A urinary balance study was conducted using diets 3 to 5 from Exp. 1 to evaluate Product V and SMB on DON urinary metabolism. A 10 d adaptation was followed by a 7 d collection using 24 barrows in a randomized complete block design. Pigs fed NC + SMB diet had greater urinary DON output ( 0.05) than pigs fed NC + Product V, with NC pigs intermediate. Daily DON excretion was lowest ( 0.05) in the NC + SMB pigs. However, degradation of DON-sulfonate back to the parent DON molecule was observed as pigs fed NC + SMB excreted more DON than they consumed (164% of daily DON intake), greater ( 0.001) than pigs fed the NC (59%) or NC + Product V (48%). Overall, Product V did not alleviate DON effects on growth nor did it reduce DON absorption and excretion. However, hydrothermally processing DON-contaminated diets with 1.0% SMB restored ADFI and improved G:F. Even so, the urinary balance experiment revealed that some of the converted DON-sulfonate can degrade back to DON under physiological conditions. While further research is needed to discern the stability of the DON-sulfonate, SMB appears promising to restore performance in pelleted DON-contaminated diets.