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The effects of feeding grains naturally contaminated with Fusarium mycotoxins with and without a polymeric glucomannan adsorbent on lactation, serum chemistry, and reproductive performance after weaning of first-parity lactating sows¹

Department of Animal and Poultry Science, University of Guelph, Guelph, Ontario, N1G2W1, Canada

	Abstract

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An experiment was conduced to investigate the effects of feeding grains naturally contaminated with Fusarium mycotoxins such as deoxynivalenol on lactation, metabolism, and reproductive performance after weaning of first parturition sows and to evaluate the efficacy of a polymeric glucomannan mycotoxin adsorbent (GMA). Thirty-six Yorkshire sows were fed 3 diets (n = 12 sows/diet) from 91 ± 3 d of gestation up to weaning on d 21 after farrowing. Diets included 1) control, 2) contaminated grains, and 3) contaminated grains + 0.2% GMA. The variables measured include ADFI, average daily BW change, serum biochemistry, milk composition, BW of litters at weaning, and weaning to estrus interval. The feeding of contaminated grains and contaminated grains + GMA reduced ADFI (P < 0.001). The feeding of contaminated grains resulted in weight loss (P = 0.007), as did the feeding of contaminated grains + GMA (P = 0.028), compared with controls, which underwent a small weight gain. There were no differences between the sows fed contaminated grains and those fed contaminated grains + GMA in average daily BW change. On the day of farrowing, total serum protein concentrations were lower for sows fed contaminated grains compared with controls (P = 0.038) and for sows fed contaminated grains compared with sows fed contaminated grains + GMA (P = 0.019). Seven days after farrowing, serum urea concentrations were lower for sows fed contaminated grains (P = 0.049) and contaminated grains + GMA (P = 0.048) compared with controls. Milk composition was not affected by treatments. There were no effects of diet on BW of litters at weaning or mortality of piglets during lactation. There was a trend for increased weaning to estrus interval in sows fed contaminated grains (P = 0.09) or contaminated grains + GMA (P = 0.08) compared with controls. It was concluded that the feeding of diets naturally contaminated with Fusarium mycotoxins to lactating sows reduces feed intake and increases BW losses. The weaning to estrus interval also tends to be longer in sows fed contaminated diets. Supplementing contaminated feed with GMA could counteract the reduction in serum protein and serum urea observed in sows fed contaminated feed.

Key Words: deoxynivalenol • Fusarium • glucomannan • mycotoxin • reproduction • sow

	INTRODUCTION

Top Abstract INTRODUCTION MATERIALS AND METHODS RESULTS DISCUSSION LITERATURE CITED

 
The natural contamination of grains by Fusarium mycotoxins is a global phenomenon to which swine are particularly sensitive (Hussein and Brasel, 2001). Reduction in feed intake of swine fed diets contaminated with deoxynivalenol (DON) has previously been described (Vesonder et al., 1979; Friend et al., 1982).

There are few reports concerning the effects of feeding sows grains naturally contaminated with Fusarium mycotoxins during lactation. Chavez (1984) found that sows fed diets contaminated with 3.3 mg of DON/kg during gestation and lactation did not exhibit differences in feed intake during lactation, but the loss of BW was significantly higher when compared with controls. There were also no differences in numbers of piglets alive at weaning. In another study, Friend et al. (1986) found that the feeding of 3.67 and 4.21 mg of DON kg^–1 of diet to boars and gilts resulted in reductions in feed intake and BW gain.

The use of adsorbents to prevent the toxic effects of Fusarium mycotoxins has been tested in swine and poultry. Raju and Devegouda (2000) reported that the use of a glucomannan mycotoxin adsorbent (GMA; Mycosorb, Alltech Inc., Nicholasville, KY) reduced the toxic effects of aflatoxin and T-2 toxin in chickens. Swamy et al. (2003) reported that GMA prevented some of the toxic effects of Fusarium mycotoxins in starter pigs.

An experiment was therefore conducted to determine the effect of feeding a blend of grains naturally contaminated with Fusarium mycotoxins on production, metabolism, and reproduction of lactating sows and the efficacy of GMA in preventing these effects.

	MATERIALS AND METHODS

Top Abstract INTRODUCTION MATERIALS AND METHODS RESULTS DISCUSSION LITERATURE CITED

 
Analytical Composition of Feedstuffs
Contaminated corn, control corn, contaminated wheat, and control wheat all were analyzed for CP, fat, NDF, ash, GE, and DM (Table 1). Soybean meal was analyzed for CP (Table 1). Metabolizable energy was calculated by using an equation of NRC (1998). All analyses were conducted according to the AOAC (1980). Diets were based on corn, wheat, and soybean meal (Table 2) and were formulated to be approximately isoenergetic and to meet or exceed the requirements of CP, Lys, Met + Cys, Thr, and Val (NRC, 1998). Diets were formulated using the formulation program MIXIT-2+ (Agricultural Software Consultants Inc., San Diego, CA) with analyzed ingredient values. Diets were analyzed for CP, fat, and ash according to the AOAC (1980; Table 2). Diets included 1) control, 2) contaminated grains, and 3) contaminated grains + 0.2% of GMA (Mycosorb, Alltech Inc., Nicholasville, KY; Table 2). Piglets were not creep fed and were weaned at d 21 of lactation.

Experimental Animals
The University of Guelph Animal Care Committee approved all animal care and protocol practices, which met the guidelines of the Canadian Council on Animal Care (1993).

A total of 36 primiparous, pregnant Yorkshire sows at 91 ± 3 d of pregnancy and 180 ± 2.76 kg of BW were selected from the breeding herd of the swine research facility. On d 35 after breeding, pregnancy status was evaluated by transabdominal ultrasonography in those sows that did not return to estrus. Pregnancy status was not reconfirmed before the beginning of the experiment. Pregnant sows were then chosen from the herd to be allotted to the experimental treatments. During pregnancy, the sows were housed in individual stalls (0.61 x 2.0 m) at the Arkell Swine Research Station of the University of Guelph. Temperature was maintained at 22 ± 2°C in the closed building.

On 91 ± 3 d of gestation, the sows were randomly assigned to each treatment in each block. One experimental group was entered each week. Each new group entering the study was treated as a new block. The experimental design, therefore, included 12 blocks and 3 treatments. All the sows began to receive 2.4 kg·sow^–1·d^–1 of the experimental diets (Table 2) until farrowing. One week before the estimated farrowing date, the sows were placed in the farrowing room in individual crates. The feed allowance from the day of farrowing until weaning at 21 d was 5.0 kg·sow^–1·d^–1. Refused feed was collected daily, air-dried, and weighed, and sows had access to water supplied by nipple waterers. All sows were fed control diets after weaning, with an allowance of 2.0 kg·sow^–1·d^–1, and had voluntary access to water supplied by nipple waterers. Cross-fostering was done immediately after farrowing to standardize to 8 piglets per sow. The reason for standardization to 8 piglets per sow was to prevent shortages of piglets if there was a low number of live piglets born. This also was intended to ensure the survival of the sows during lactation, which could have been at risk if the situation of low feed intake and large litter occurred. The live litter weight and the litter weights after cross-fostering were recorded.

Experimental Variables Studied
Feed intake of the sows was recorded. Sows and piglets were individually weighed on the date of farrowing and on d 7, 14, and 21 after farrowing. If a piglet died during the first 48 h of life, another of similar weight replaced it.

Blood was collected on the day of farrowing and d 7 after farrowing from the sinus opthalmicus of each sow into vials that did not contain anticoagulant. Serum concentrations of ß-hydroxybutyrate, haptoglobin, total serum protein, albumin, globulin, albumin:globulin ratio, glucose, urea, cholesterol, creatinine, total bilirubin, conjugated bilirubin, unconjugated bilirubin, Ca, P, Mg, Na, K, Cl, and activities of alkaline phosphatase, glutamate dehydrogenase, aspartate aminotransferase, -glutamyltransferase, and creatine kinase were determined using a Hitachi 911 autoanalyzer (Roche Diagnostics, Division of Hoffman-la Roche Limited, Montreal, QC, Canada). Due to sampling difficulties, it was not possible to obtain a blood sample from 1 sow on d 7 after farrowing. Haptoglobin and ß-hydroxy butyrate concentrations also could not be determined from blood samples obtained from 2 sows on the day of farrowing and d 7 after farrowing.

Milk was collected during the first 8 h after farrowing, as well as on d 7, 14, and 21 of lactation. Before milk collection, the sows were injected intramuscularly with 20 IU of oxytocin. Five minutes later, the sows were manually milked, with collection of up to 50 mL from the 4 anterior teats of each sow. Fat, CP, and lactose were determined using a Foss MilkoScan 4000 IR analyzer (Foss North America, Eden Prairie, MN). Two control sows were unable to be milked on d 14 and 21. One contaminated grains + 0.2% of GMA-fed sow was unable to be milked on d 14 and 21.

After weaning, the sows were allocated to pens (4 x 5 m) in groups of 5 sows and fed 2 kg·sow^–1·d^–1 of a diet containing 14% CP and 13.38 MJ of ME, on an as-fed basis. From d 2 after weaning, sows were exposed to fence line contact with mature boars twice daily for 15 min at 0900 and 1500 to stimulate estrus. Sows were evaluated in the morning and in the afternoon for heat detection by using the back pressure test (Van den Brand et al., 2000). If estrus was detected, the date was recorded to determine the weaning to estrus interval.

Statistical Analysis
A randomized complete block design with 3 treatments in 12 blocks was utilized. The analyses of data were made by ANOVA using the GLM procedure (SAS Inst. Inc., Cary, NC). Each sow represented an experimental unit for all variables tested. The independent variables were the experimental diets. Dependent variables were ADFI; average daily BW change; serum chemistry; liver enzyme activity; weight of the litter at birth and d 7, 14, and 21; and weaning to estrus interval. To assess diet effects, the dietary treatment means were compared by Tukey’s multiple comparison test, and significance was declared at P < 0.05. The multiple comparison test was employed to answer 2 basic questions: 1) is the response variable negatively affected by the mycotoxins (control vs. contaminated grain diet), and 2) does the GMA restore performance (control vs. contaminated grain + GMA; and contaminated grain diet vs. contaminated grain + GMA).

	RESULTS

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Chemical Composition of Raw Materials and Mycotoxin Content of Diets
Concentrations of CP, NDF, fat, and ash were greater for contaminated corn and contaminated wheat compared with control grains (Table 1). Contaminated diet and contaminated diet + GMA had similar concentrations of zearalenone, DON, and 15-acetyl DON. The highest concentration of mycotoxin found in contaminated diets was DON (Table 3), and there was a combination of Fusarium mycotoxins in the contaminated diet and in the contaminated diet + GMA (Table 3).

Feed Intake and Weight Change of Sows in the Lactation Period
In lactation the ADFI was reduced in sows fed contaminated grains compared with control (P < 0.001) and in sows fed contaminated grains + GMA compared with control (P < 0.001; Table 4). There was a reduction of average daily BW in sows fed contaminated grains compared with control (P = 0.008) and in sows fed the contaminated grains + GMA compared with control (P = 0.029; Table 4).

Weaning to Estrus Interval
There was a trend toward longer weaning to estrus interval comparing sows fed contaminated grains with controls (P = 0.094). A similar trend was seen in weaning to estrus interval comparing sows fed contaminated grains + GMA with controls (P = 0.079; Table 4).

	DISCUSSION

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In the current study there were differences in raw material composition, which were also found by Friend et al. (1982), Hamilton and Trenholm (1984), and Friend et al. (1986) who reported that contaminated wheat had increased CP content compared with controls. Friend et al. (1982) also reported that contaminated wheat had greater values for CP and crude fiber compared with control wheat.

Mycotoxins are unevenly distributed in grains, which explain small differences in concentrations of mycotoxins in diets (Davis et al., 1980). Other causes of differences in mycotoxin concentrations in feed are errors in sampling, deterioration in storage, and variability in laboratory analysis (Friend et al., 1983).

The reduction in feed intake observed in sows fed contaminated grains in the current study differs from the results of Chavez (1984), who reported that feed consumption was not reduced significantly during lactation of sows fed diets containing 1.3, 2.4, and 3.3 ppm of DON compared with control diets that contained 0.17 ppm of DON. The results of the current study also disagrees with Friend et al. (1986) who reported that sows fed diets containing 3.8 and 6.2 ppm of DON during lactation did not show a significant reduction of feed intake. In the experiment of Chavez (1984) the average feed intake of sows fed the control diet was 4.09 kg·sow^–1·d^–1, and in the experiment of Friend et al. (1986) the average feed intake of sows fed the control diet was 3.05 kg·sow^–1·d^–1. These are lower than the corresponding value for controls in the current experiment (4.87 kg·sow^–1·d^–1) in the lactation period.

The significant losses of BW of sows fed contaminated grains and contaminated grains + GMA observed in the current experiment agrees with Chavez (1984) who reported that the feeding of diets containing 1.3 and 2.4 ppm of DON to sows resulted in significantly greater BW losses compared with controls during lactation. In the same experiment, however, sows fed a diet containing 3.3 ppm did not show BW losses differing from controls. Friend et al. (1986) reported that sows fed diets containing up to 6.2 ppm of DON showed no differences in BW losses during lactation. It is important, however, that a blend of naturally contaminated feed-stuffs was used in the current study and that several mycotoxins were found to be present in addition to DON. Earlier reports indicated only DON concentrations in contaminated feeds. Discrepancies in results may be due, in part, to the presence of additional mycotoxins in the current study.

The feeding of diets containing 10.5 ppm of DON to 8.4-kg barrows for 3 wk did not affect serum protein concentrations (Lun et al., 1985). In another report, Chavez and Rheaume (1986) did not find differences in plasma protein concentrations in 22-kg pigs when fed diets containing 6 ppm of DON for 12 wk. The feeding of 2.5 ppm of DON to 11.4-kg pigs did not result in a reduction in serum protein concentrations compared with controls (Harvey et al., 1989). Bergsjø et al. (1993) reported that the feeding of a diet containing oats naturally contaminated with 3.5 ppm of DON to growing pigs did not result in any direct effects of DON on serum biochemistry. The feeding of 2.3 and 4.6 ppm of DON to 28-kg pigs, and the feeding of 1.4 and 2.7 ppm of DON to 70-kg pigs did not reduce total serum protein concentration (Dänike et al., 2004). Trenholm et al. (1994) reported that the feeding of diets contaminated with graded concentrations of DON added as pure compound at 0, 3.4, 5.1, 7.7, 8.2, 10.7, and 19.1 ppm to 35-kg pigs resulted in a reduction in concentrations of total blood protein for all the groups with the group fed with 7.7 ppm of DON being the exception. Another group in the same experiment fed 7.3 ppm of DON from naturally contaminated grain had reduced total blood protein concentrations (Trenholm et al., 1994). The reduction in total serum protein concentrations observed on the farrowing d in sows fed contaminated grains and the trend toward reduced total serum protein concentrations on d 7 after farrowing in sows fed contaminated grains compared with controls agrees with the results reported by Trenholm et al. (1994). Effects such as the reduction of serum protein concentrations have been attributed to the reduction of feed intake. In the current experiment, reductions of CP intake could reduce hepatic fractional protein synthesis. Wykes et al. (1996) reported that hepatic fractional protein synthesis rate was reduced when 8-kg piglets were fed a low protein diet (3% CP) compared with control piglets. It was reported in another study that fractional synthesis rate of albumin and other proteins such as transferrin, retinol binding protein, fibrinogen, and haptoglobin were reduced in 3-wk-old piglets fed a 3% protein diet compared with controls fed a 20% protein diet (Jahoor et al., 1996). Protein synthesis in liver is reduced, however, as the result of the toxic effect of DON in growing pigs (Rotter et al., 1995). In another study, Chowdhury and Smith (2005) reported that the hepatic fractional protein synthesis in laying hens was reduced after 4 wk of feeding diets containing 11.9 ppm of DON. There is another report, however, that shows that hepatic fractional protein synthesis in 23-kg pigs was not reduced after the oral doses of 77 and 83 µg of DON·kg^–1 and i.v. doses of 53 µg of DON·kg^–1 (Dänike et al., 2006). In the current study the feeding of contaminated grains + GMA resulted in a reduction in the feed and CP intake as great as that observed for sows fed contaminated grains, but no reduction in serum protein concentrations were observed in sows fed contaminated grains + GMA. We can conclude, therefore, that the reduction in total serum protein concentrations and in serum globulin concentrations were not only due to reduced feed intake. The lack of differences in total serum protein concentrations between sows fed contaminated grains + GMA and controls suggests that GMA prevented the reduction of hepatic protein synthesis caused by Fusarium mycotoxins. These data support the hypothesis that the reduced total serum protein concentrations were a direct effect of Fusarium mycotoxins such as DON and 15-acetyl DON on protein synthesis rates. It can also be concluded that there is a preventive effect of GMA on the inhibition of protein synthesis in liver caused by the feeding of diets containing grains naturally contaminated with DON to lactating sows.

The tendency toward reduced serum globulin concentrations on d of farrowing in sows fed contaminated grains compared with controls and to contaminated diets + GMA, resembles those data reported by Prelusky et al. (1994) who fed piglets (10 to 13 kg) diets containing 3 ppm of DON and observed a reduction of serum globulin concentrations. Prelusky et al. (1994) concluded that globulin was reduced as the result of the toxic effect of DON and not because of reduced feed intake. Rotter et al. (1994) also found a linear reduction (P = 0.01) in serum concentrations of -globulin in 11-kg barrows arising from increasing dietary DON concentrations. Pair-fed pigs did not have reduced serum -globulin concentrations even though feed intake was reduced. Rotter et al. (1994) concluded that the reduction in serum -globulin concentrations were due to the effect of DON and not due to reduced feed intake. The lack of a reduction of serum albumin concentrations observed in the current experiment also agrees with data of Prelusky et al. (1994), who reported that albumin was not reduced after piglets were fed diets containing 3 ppm of DON. Rotter et al. (1994) reported a linear increase in serum albumin concentrations (P = 0.01) after increasing concentrations of DON were fed to 11-kg barrows. In the current study, the trend toward an increase in albumin:globulin ratio in sows fed contaminated grains compared with sows fed control and with sows fed contaminated grains + GMA on the day of farrowing agrees with the finding of Rotter et al. (1994), who reported a linear increase (P = 0.002) in the albumin:globulin ratio due to increases in dietary DON fed to barrows. Pair-fed barrows did not have, however, increases in albumin to globulin ratio compared with controls. Overall, the findings in the current study support the concept that changes in serum protein concentrations, particularly globulins, were caused by the feeding of diets naturally contaminated with Fusarium mycotoxins to sows, and that dietary supplementation with GMA prevents these changes.

Harvey et al. (1989) reported that concentrations of blood urea nitrogen were not affected after feeding 6-wk-old barrows 3 ppm of DON for 28 d. In the current experiment, DON did not affect the serum urea concentrations on the day of farrowing. The d 7 after farrowing, sows fed contaminated grains showed a reduction in serum urea concentrations compared with controls. Sows fed contaminated grains + GMA also showed reduced serum urea concentrations. At this point in lactation, all sows fed the contaminated diets were losing weight, which could be interpreted as sows mobilizing body tissues including fat and skeletal muscle to support milk production. Such body tissue mobilization would involve increased catabolism of fat and muscular protein, and an increase in blood urea concentrations would be expected.

The trend toward reduction in concentrations of serum cholesterol on d 7 after farrowing in sows fed contaminated grains + GMA compared with controls can be attributed to the reduction of feed intake or to the feeding of contaminated diets. In a study with 8-kg piglets, Young et al. (1983) reported a reduction in feed intake but an increase in serum cholesterol concentrations with increasing dietary DON concentrations. It is difficult to determine, therefore, if this effect is the result of the reduced feed intake of the sows during lactation or if it is a toxic effect of Fusarium mycotoxins. To the best of our knowledge there are no other reports of a reduction in serum cholesterol concentrations in lactating sows when a reduction in feed intake was seen after exposure to Fusarium mycotoxins. Some trends were seen in serum chemistry on the day of farrowing that were not present 7 d later. This may have been due to the physiological stress of farrowing.

In hepatic parenchyma, some enzymes such as glutamate dehydrogenase and arginase are present in high activity. Increases in serum activities of these enzymes indicates moderately specific hepatocellular damage in most species (Boyd, 1983). In hepatobiliary obstruction, serum -glutamyl transferase is noticeably increased, but there is little increase in hepatocellular necrosis (Boyd, 1983). Glutamate dehydrogenase is elevated after severe mitochondrial damage. After liver damage some enzymes such as glutamate dehydrogenase, -glutamyl transferase, and aspartate aminotransferase are high in serum and have been used as an indicator of liver damage (Wills, 1985). In the current experiment the rise in aspartate aminotransferase activity in sows fed contaminated grains + GMA and the trend toward higher activity seen in sows fed contaminated grains the day of farrowing (Table 6) indicates some hepatic damage and an inability of GMA to prevent this effect. Physiological lower and upper serum concentrations of aspartate aminotransferase are 15.3 to 55.3 U/L (Boyd, 1984). No differences were seen in serum activities of other hepatic enzymes on the farrowing day and on d 7 after farrowing. These findings agree with those reported by Dänike et al. (2004) who found that aspartate aminotransferase, glutamate dehydrogenase, and -glutamyl transferase were not affected in 70-kg pigs fed with 1.4 and 2.7 ppm of DON for 3 wk. In another publication, serum -glutamyl transferase activity was not different in 12.4- to 32.5-kg pigs fed 0.2, 0.8, 1.0, 1.9, and 3.9 ppm of DON (Döll et al., 2003). Tieman et al. (2006) reported that feeding 103-kg prepubertal gilts 0.21, 3.07, 6.1, and 9.57 ppm of DON did not affect serum activity of -glutamyl transferase. In the same experiment, alanine aminotransferase and aspartate aminotransferase were higher in gilts fed 6.1 and 9.57 ppm of DON. The same authors also reported that histopathology studies revealed a reduction in liver glycogen in a dose-dependent manner and increased collagen fibrils in the interlobular connective tissue. In the same study, Tieman et al. (2006) reported that at the ultra-structural level, groups fed 6.1 and 9.57 ppm of DON showed a marked increase in smooth endoplasmic reticulum, a reduction of ribosomes, and a rise in fatty vacuoles. The authors concluded that even in the relative absence of an effect of diet on serum levels of hepatic enzymes, liver damage was evident at the histological and ultra-structural levels. Physiological concentrations of serum total bilirubin have been described as 0.3 to 8.2 µmol/L (Boyd, 1984), and up to 30% of the total bilirubin may be conjugated (Pratt and Kaplan, 2001b). In the current experiment, serum conjugated bilirubin concentrations were in the physiological range. The elevated serum conjugated bilirubin concentrations seen in sows fed contaminated grain and contaminated grain + GMA when compared with controls, nevertheless, suggest some liver or biliary tract disease (Pratt and Kaplan, 2001a). Elevated serum concentrations of aspartate aminotransferase and alanine aminotransferase are seen when liver cell membrane damage occurs (Pratt and Kaplan, 2001a). Biliary cholestasis is characterized by elevated activities of alkaline phosphatase, 5'-nucleotidase, and -glutamyltransferase (Pratt and Kaplan, 2001a). Because in the current experiment an increase in activity of aspartate aminotransferase was seen, even though alkaline phosphatase and -glutamyltransferase were not elevated, it is suggested there was some hepatic cell damage.

The lack of differences of milk composition that were observed in this experiment are in agreement with the report of Friend et al. (1986). Neither the feeding of diets contaminated with Fusarium mycotoxins nor the reduction of feed intake during lactation had effects on milk composition during the 21 d of lactation.

The lack of effect of diet on BW of piglets at birth and at weaning shows that milk production of sows was not affected by the feeding of diets contaminated with Fusarium mycotoxins. The reduction in feed intake was likely compensated for by the mobilization of body reserves including fat and skeletal muscle. The lack of difference in piglet BW at weaning can be explained by the extraction rate of AA in mammary gland being increased as dietary CP concentration was reduced from 24 to 18 to 12% in lactating sows (Perez Laspiur and Trottier, 2006). This means that sows have increased uptake of AA by mammary gland when there is a reduction in CP intake in lactation.

There was no significant effect of diet on the weaning to estrus interval. The weaning to estrus interval, however, was increased 8 d compared with controls, which is remarkable. Reductions in protein intake during lactation have been associated with an extension of the weaning to estrus interval. King and Martin (1989) concluded that a restriction in protein intake during lactation reduces LH concentrations in plasma at weaning and that a restriction in protein intake prevents the developing of a high pulse frequency of LH. This fact is a cause of postweaning anestrus that is most frequent in first-litter sows. Koketsu et al. (1996a) found that reproductive failure has a dose:response relationship with ADFI. Koketsu et al. (1996b) also concluded that low energy intake during lactation increases the weaning to estrus interval, and also influences pulse frequency and amplitude of LH. Tokach et al. (1992) observed that there was an interaction between lysine and energy intake that influences the weaning to estrus interval and that the effect of lysine intake on LH secretion was higher with increased energy intake. Koketsu et al. (1996b) found a clear effect of daily energy intake on weaning to estrus interval in sows fed 45 g of lysine/d. Lower energy intake resulted in longer weaning to estrus intervals. A reduction in feed intake during lactation was also observed in this experiment that could increase the weaning to estrus interval. The losses of skeletal muscle protein, the losses of body fat, or both were probably involved in extending the weaning to estrus interval of sows fed contaminated diets compared with controls. To the best of our knowledge there are no reports indicating that DON directly affects LH pulse, frequency and amplitude, or weaning to estrus interval in sows. The effect of zearalenone on reproduction in sows has been well documented. Chang et al. (1979) reported that like the activity of estrogen, zearalenone inhibits the release and secretion of FSH to depress the maturation of ovarian follicles during the preovulation stage. This results in atresia of follicles becoming the prominent histological trait and resulting in atrophy of ovaries. Etienne and Jemmali (1982) similarly reported an experiment showing zearalenone to have effects on reproduction of sows when sows were fed a diet contaminated with 3.6 ppm of zearalenone. Estrus was not detected in 45% of the animals 50 d after puberty.

It was concluded that the feeding of a diet containing grains naturally contaminated with Fusarium mycotoxins to first parturition sows from farrowing until weaning reduces ADFI. Body weight change and total serum protein were also affected, although milk composition and piglet BW at weaning were not influenced. Supplementing contaminated diets with GMA could not prevent the reduction in feed intake, BW losses, and the tendency to longer weaning to estrus intervals. It is hypothesized that these effects may be due to mobilization of body reserves in sows fed contaminated grains. Such depletion in body condition tends to increase the weaning to estrus interval.

In summary, the feeding of naturally contaminated grains with Fusarium mycotoxins to lactating sows reduces feed intake and increases BW losses. Reduction in feed intake or reduced hepatic protein synthesis arising from the feeding of Fusarium mycotoxins could cause the reduction in serum protein concentrations. Reduction of feed intake during lactation did not reduce litter BW at weaning. Feeding sows diets naturally contaminated with Fusarium mycotoxins did not elicit changes in milk composition or in milk production. The reduced feed intake and losses of body tissues tends to increase the weaning to estrus interval. The feeding of Fusarium mycotoxins to lactating sows, therefore, should be avoided.

	Footnotes

 
¹ This study was supported in part by the Ontario Ministry of Agriculture, Food and Rural Affairs and Alltech Inc., Nicholasville, KY. The authors thank the staff of the Arkell Swine Research Center including Nancy Wedel, Vern Wideman, and Joe Rooyakkers for the valuable help in the management and care of the sows. The assistance of Mojtaba Yegani during the experimental period is appreciated.

² Corresponding author: tsmith{at}uoguelph.ca

Received for publication April 5, 2006. Accepted for publication February 16, 2007.

	LITERATURE CITED

Top Abstract INTRODUCTION MATERIALS AND METHODS RESULTS DISCUSSION LITERATURE CITED

 


AOAC. 1980. Official Methods of Analysis. 13th ed. Assoc. Off. Anal. Chem., Washington, DC.

Bergsjø, B., W. Langseth, I. Nafstad, J. H. Jansen, and H. J. S. Larsen. 1993. The effects of naturally deoxynivalenol-contaminated oats on the clinical condition, blood parameters, performance and carcass composition of growing pigs. Vet. Res. Comm. 17:283–294.[CrossRef][Medline]

Boyd, J. W. 1983. The mechanisms relating to increases in plasma enzymes and isoenzymes in diseases of animals. Vet. Clin. Pathol. 12:9–24.[Medline]

Boyd, J. W. 1984. The interpretation of serum biochemistry test results in domestic animals. Vet. Clin. Pathol. 13:7–14.[Medline]

Canadian Council on Animal Care. 1993. Guide to the care and use of experimental animals. Volume 1. http://www.ccac.ca/en/CCAC_Programs/Guidelines_Policies/GUIDES/ENGLISH/toc_V1.htm Accessed Jun. 10, 2004.

Chang, K., H. J. Kurtz, and J. Mirocha. 1979. Effects of the mycotoxin zearalenone on swine reproduction. Am. J. Vet. Res. 40:1260–1267.[Medline]

Chavez, E. R. 1984. Vomitoxin-contaminated wheat in pig diets: Pregnant and lactating gilts and weaners. Can. J. Anim. Sci. 64:717–723.

Chavez, E. R., and J. A. Rheaume. 1986. The significance of the reduced feed consumption observed in growing pigs fed vomitoxin-contaminated diets. Can. J. Anim. Sci. 66:277–287.

Chowdhury, S. R., and T. K. Smith. 2005. Effects of feeding grains naturally contaminated with Fusarium mycotoxins on hepatic fractional protein synthesis rates of laying hens and the efficacy of a polymeric glucomannan mycotoxin adsorbent. Poult. Sci. 84:1671–1674.[Abstract/Free Full Text]

Dänike, S., T. Goyards, S. Döll, M. Grove, M. Spolder, and G. Flachowsky. 2006. Effects of Fusarium toxin deoxynivalenol on tissue protein synthesis in pigs. Toxicol. Lett. 165:297–311.[CrossRef][Medline]

Dänike, S., H. Valent, F. Klobasa, S. Döll, M. Ganter, and G. Flachowsky. 2004. Effects of graded levels of Fusarium toxin contaminated wheat in diets for fattening pigs on growth performance, nutrient digestibility, deoxynivalenol balance and clinical serum characteristics. Arch. Anim. Nutr. 58:1–17.[CrossRef][Medline]

Davis, N. D., J. W. Dickens, R. L. Freie, P. B. Hamilton, O. L. Showell, T. D. Wyllie, and J. F. Fulkerson. 1980. Protocols for surveys, sampling, post-collection handling, and analysis of grain samples involved in mycotoxin problems. J. Assoc. Off. Anal. Chem. 63:95–102.[Medline]

Döll, S., S. Dänike, K.-H. Ueberschar, H. Valenta, U. Schnurrbusch, M. Ganter, F. Klosaba, and G. Flachowsky. 2003. Effects of graded levels of Fusarium toxin contaminated maize in diets for female weaned piglets. Arch. Anim. Nutr. 57:311–334.[CrossRef]

Etienne, M., and M. Jemmali. 1982. Effects of Zearalenone (F2) on estrous activity and reproduction in gilts. J. Anim. Sci. 55:1–10.[Abstract/Free Full Text]

Friend, D. W., B. K. Thompson, H. L. Trenholm, K. E. Hartin, and D. B. Prelusky. 1986. Effects of feeding deoxynivalenol (DON)-contaminated wheat diets to pregnant and lactating gilts and on their progeny. Can. J. Anim. Sci. 66:229–236.

Friend, D. W., H. L. Trenholm, J. I. Elliot, B. K. Thompson, and K. E. Hartin. 1982. Effect of feeding vomitoxin-contaminated wheat to pigs. Can. J. Anim. Sci. 62:1211–1222.

Friend, D. W., H. L. Trenholm, P. S. Fiser, B. K. Thompson, and K. E. Hartin. 1983. Effect on dam performance and fetal development of deoxynivalenol (vomitoxin) contaminated wheat in the diet of pregnant gilts. Can. J. Anim. Sci. 63:689–698.

Hamilton, R. M. G., and H. L. Trenholm. 1984. Observations on the chemical and nutritive content of winter and spring wheats contaminated with deoxynivalenol (vomitoxin). Anim. Food Sci. Technol. 11:293–300.[CrossRef]

Harvey, R. B., L. F. Kubena, W. E. Huff, D. E. Corrier, D. E. Clark, and T. D. Phillips. 1989. Effects of aflatoxin, deoxynivalenol, and their combinations in the diets of growing pigs. Am. J. Vet. Res. 50:602–606.[Medline]

Hussein, H. S., and J. M. Brasel. 2001. Toxicity, metabolism, and impact of mycotoxins on humans and animals. Toxicol. 167:101–134.[CrossRef][Medline]

Jahoor, F., S. Bhattiprolu, M. Del Rosario, D. Burrin, L. Wykes, and M. Frazer. 1996. Chronic protein deficiency differentially affects the kinetics of plasma proteins in young pigs. J. Nutr. 126:1489–1495.[Abstract/Free Full Text]

King, R. H., and G. B. Martin. 1989. Relationship between protein intake during lactation, LH levels and oestrus activity in first-litter sows. Anim. Reprod. Sci. 19:283–292.[CrossRef]

Koketsu, Y., G. D. Dial, J. E. Pettigrew, and V. L. King. 1996a. Feed intake pattern during lactation and subsequent reproductive performance of sows. J. Anim. Sci. 74:2875–2884.[Abstract]

Koketsu, Y., G. D. Dial, J. E. Pettigrew, W. E. March, and V. L. King. 1996b. Influence of imposed feed intake patterns during lactation on reproductive performance and on circulating levels of glucose, insulin, and luteinizing hormone in primiparous sows. J. Anim. Sci. 74:1036–1046.[Abstract]

Lun, K. A., L. G. Young, and J. H. Lumsdem. 1985. The effects of vomitoxin and feed intake on the performance and blood characteristics of young pigs. J. Anim. Sci. 61:1178–1185.[Abstract/Free Full Text]

NRC. Nutrient Requirements of Swine. 1998. Natl. Acad. Sci., Washington, DC.

Perez Laspiur, J., and N. L. Trottier. 2006. Dietary protein concentration alter amino acid extraction rate across the porcine mammary gland during lactation. J. Anim. Sci. 84 (Suppl. 1)/J. Dairy Sci. 89(Suppl.1):394.

Pratt, D. S., and M. M. Kaplan. 2001a. Evaluation of liver function. Pages 1712–1713 in Harrison’s Principles on Internal Medicine. 15th ed. E. Braunwald, A. S. Fauci, D. L. Casper, S. L. Hauser, D. L. Longo, and J. L. Jameson, ed. McGraw-Hill, New York, NY.

Pratt, D. S., and M. M. Kaplan. 2001b. Jaundice. Page 255 in Harrison’s Principles on Internal Medicine. 15th ed. E. Braunwald, A. S. Fauci, D. L. Casper, S. L. Hauser, D. L. Longo, and J. L. Jameson, ed. McGraw-Hill, New York, NY.

Prelusky, D. B., R. G. Gerdes, K. L. Underhill, B. A. Rotter, P. Y. Jui, and H. L. Trenholm. 1994. Effects of low-level dietary deoxynivalenol on haematological and clinical parameters of the pig. Nat. Toxins 2:97–104.[Medline]

Raju, M. V. L. N., and G. Devegouda. 2000. Influence of esterified-glucomannan on performance and organ morphology, serum biochemistry and haematology in broilers exposed to individual and combined mycotoxicoses (aflatoxin, ochratoxin and T-2 toxin). Br. Poult. Sci. 41:640–650.[Medline]

Raymond, S. L., T. K. Smith, and H. V. L. N. Swamy. 2003. Effects of feeding a blend of grains naturally contaminated with Fusarium mycotoxins on feed intake, serum chemistry, and hematology of horses, and the efficacy of a polymeric glucomannan mycotoxin adsorbent. J. Anim. Sci. 81:2123–2130.[Abstract/Free Full Text]

Rotter, B. A., B. K. Thompson, and M. Lessard. 1995. Effects of deoxynivalenol-contaminated diet on performance and blood parameters in growing swine. Can. J. Anim. Sci. 75:297–302.

Rotter, B. A., B. K. Thompson, M. Lessard, H. L. Trenholm, and H. Tryphonas. 1994. Influence of low-level exposure to Fusarium mycotoxins on selected immunological and hematological parameters in young swine. Fundam. Appl. Toxicol. 23:117–124.[CrossRef][Medline]

Swamy, H. V. L. N., T. K. Smith, E. J. MacDonald, N. A. Karrow, B. Woodward, and H. J. Boermans. 2003. Effects of feeding a blend of grains naturally contaminated with Fusarium mycotoxins on growth and immunological measurements of starter pigs, and the efficacy of a polymeric glucomannan mycotoxin adsorbent. J. Anim. Sci. 81:2792–2803.[Abstract/Free Full Text]

Tieman, U., K.-P. Brüssow, U. Küchenmeister, L. Jonas, P. Kohlschein, R. Pöhland, and S. Dänike. 2006. Influence of diets with cereal grains contaminated by graded levels of two Fusarium toxins on selected enzymatic and histological parameters of liver in gilts. Food Chem. Toxicol. 44:1228–1235.[CrossRef][Medline]

Tokach, M. D., J. E. Pettigrew, G. D. Dial, J. E. Wheaton, B. A. Crooker, and L. J. Johnston. 1992. Characterization of luteinizing hormone secretion in the primiparous, lactating sow:relationship to blood metabolites and return-to-estrus interval. J. Anim. Sci. 70:2195–2201.[Abstract]

Trenholm, H. L., B. C. Foster, L. L. Charmley, B. K. Thompson, K. E. Hartin, R. W. Coppock, and M. A. Albassam. 1994. Effects of feeding diets containing Fusarium (naturally) contaminated wheat or pure deoxynivalenol (DON) in growing pigs. Can. J. Anim. Sci. 74:361–369.

Van den Brand, H., S. J. Dieleman, N. M. Soede, and B. Kemp. 2000. Dietary energy source at two feeding levels during lactation of primiparous sows: I. Effects on glucose, insulin, and luteinizing hormone and on follicle development, weaning-to-estrus interval, and ovulation rate. J. Anim. Sci. 78:396–404.[Abstract/Free Full Text]

Vesonder, R. F., A. Ciegler, H. R. Burmeister, and A. H. Jensen. 1979. Acceptance by swine and rats of corn amended with trichothecenes. Appl. Environ. Microbiol. 38:344–346.[Abstract/Free Full Text]

Young, L. G., L. McGirr, V. E. Valli, J. H. Lumsden, and A. Lun. 1983. Vomitoxin in corn fed to young pigs. J. Anim. Sci. 57:655–664.[Abstract/Free Full Text]

Wills, E. D. 1985. Biochemical diagnosis. Pages 489–499 in Biochemical Basis of Medicine. E. D. Wills, ed. Wright & Sons Ltd., Bristol, UK.

Wykes, L. J., M. Fiorotto, D. G. Burrin, M. Del Rosario, M. E. Frazer, W. G. Pond, and F. Jahoor. 1996. Chronic low protein intake reduces tissue protein synthesis in a pig model of protein malnutrition. J. Nutr. 126:1481–1488.[Abstract/Free Full Text]

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