镰刀菌毒素对断奶仔猪血清酶、肝脏抗氧化功能及组织病理学的影响

试验旨在研究镰刀菌毒素污染日粮对断奶仔猪血清酶、肝脏抗氧化功能及组织病理学的影响。选择35日龄体重为(8.45±0.94) kg的健康三元杂交(杜×长×大)断奶雌性仔猪40头,随机分为2组,每组20个重复,每个重复1头猪。对照组饲喂基础日粮,试验组饲喂用霉变玉米和霉变玉米蛋白粉替代基础日粮中50%的玉米和玉米蛋白粉配制而成的镰刀菌毒素污染日粮(玉米赤霉烯酮(ZEN) 0.90 mg/kg,呕吐毒素(DON) 1.43 mg/kg,烟曲霉毒素(FUM) 5.85 mg/kg)。仔猪单栏饲喂,预试期7 d,正试期35 d。结果表明:①与对照组相比,试验组断奶仔猪血清中谷草转氨酶(AST)、谷丙转氨酶(ALT)和碱性磷酸酶(ALP)活性均显著升高(P<0.05),肝脏相对重显著降低(P<0.05);②与对照组相比,试验组断奶仔猪血清和肝脏中谷胱甘肽过氧化物酶(GSH-Px)和总超氧化物歧化酶(T-SOD)活性均显著降低(P<0.05),而丙二醛(MDA)含量显著升高(P<0.05);③病理组织学观察发现,试验组断奶仔猪肝脏出现一定程度的组织损伤,部分肝小叶边缘发生明显的炎性细胞浸润,肝细胞发生局部空泡变性。由此可知,镰刀菌毒素污染日粮(0.90 mg/kg ZEN,1.43 mg/kg DON,5.85 mg/kg FUM)饲喂断奶仔猪可引起仔猪血清酶活性改变,肝脏抗氧化功能降低,肝脏组织出现一定程度的病理损伤,从而影响肝脏功能的发挥。     

镰刀菌毒素对断奶仔猪脾脏抗氧化能力和白细胞介素-1β、白细胞介素-6分布和表达的影响

本试验旨在研究自然霉变饲粮中镰刀菌毒素对断奶仔猪脾脏抗氧化能力和白细胞介素-1β(IL-1β)、白细胞介素-6(IL-6)分布和表达的影响。选择35日龄平均体重为(8.45±0.94)kg的健康三元杂交(杜×长×大)断奶仔猪母猪40头,随机分为2组,每组20头。对照组饲喂基础饲粮,镰刀菌毒素组饲喂含镰刀菌毒素[玉米赤霉烯酮(ZEN)0.90 mg/kg;呕吐毒素(DON)1.43mg/kg,烟曲霉毒素(FUM)5.85 mg/kg]的试验饲粮。预试期7d,正试期35d。结果表明:1)与对照组相比,镰刀菌毒素显著降低了断奶仔猪血清和脾脏谷胱甘肽过氧化物酶(GSH-Px)和总超氧化物歧化酶(T-SOD)活性(P0.05),显著升高了丙二醛(MDA)含量(P0.05)。2)镰刀菌毒素使断奶仔猪脾脏白髓区明显变小,红髓区扩张且出现近圆形小空洞,动脉周围淋巴鞘中淋巴细胞数量较少。3)镰刀菌毒素导致断奶仔猪脾脏IL-1β和IL-6阳性细胞主要集中于白髓边缘,且靠近血窦的地方阳性点更多。4)与对照组相比,镰刀菌毒素显著升高了断奶仔猪脾脏IL-1β和IL-6mRNA相对表达量(P0.05)。由此可见,饲粮中镰刀菌毒素显著影响断奶仔猪血清和脾脏抗氧化能力,并通过改变脾脏IL-1β和IL-6的分布和表达,降低脾脏的免疫功能。     

镰刀菌毒素污染饲粮导致的断奶仔猪肝脏损伤与自然修复研究

本试验旨在研究阶段性饲喂镰刀菌毒素污染饲粮对仔猪血清和肝脏生化指标、抗氧化指标以及肝脏炎性细胞因子白细胞介素-1β(IL-1β)、白细胞介素-6(IL-6)mRNA相对表达量的影响。选用体重为(8.45±0.94)kg的35日龄"杜×长×大"雌性仔猪30头,随机分为3组,每组10个重复,每个重复1头猪。对照组持续饲喂基础饲粮,镰刀菌毒素组持续饲喂镰刀菌毒素污染饲粮(玉米赤霉烯酮0.90 mg/kg,呕吐毒素1.43 mg/kg,烟曲霉毒素5.85 mg/kg),自然恢复组在饲喂镰刀菌毒素污染饲粮35 d后,改饲喂基础饲粮。预试期7 d,正试期56 d。结果表明:1)与对照组相比,镰刀菌毒素组仔猪肝脏相对重量显著升高(P0.05),血清谷丙转氨酶(ALT)、谷草转氨酶(AST)和碱性磷酸酶(ALP)活性显著升高(P0.05),血清总蛋白(TP)和球蛋白(GLB)含量显著降低(P0.05),血清谷胱甘肽过氧化物酶(GSH-Px)、血清和肝脏总超氧化物歧化酶(T-SOD)活性显著下降(P0.05),血清和肝脏丙二醛(MDA)含量显著升高(P0.05);肝脏炎性细胞因子IL-1β和IL-6 mRNA相对表达量显著升高(P0.05)。2)经21 d自然恢复后,与镰刀菌毒素组相比,自然恢复组仔猪肝脏相对重量有所降低(P0.05),血清AST、ALT和ALP活性显著降低(P0.05),血清TP和GLB含量显著升高(P0.05),血清T-SOD活性显著升高(P0.05),血清和肝脏GSH-Px、肝脏T-SOD活性有所升高(P0.05),血清和肝脏M DA含量显著降低(P0.05),肝脏炎性细胞因子IL-1β和IL-6 mRNA相对表达量显著降低(P0.05)。由此可见,本试验条件下,长期饲喂镰刀菌毒素能够造成仔猪肝脏损伤,影响肝脏的抗氧化、蛋白质合成和免疫功能,而经过21 d恢复期,仔猪肝脏抗氧化和免疫功能得到了一定程度的改善。     

Effects of purified zearalenone on growth performance, organ size, serum metabolites, and oxidative stress in postweaning gilts

Zearalenone (ZEA), an estrogenic mycotoxin, is produced mainly by Fusarium fungi. Previous studies indicated that acute ZEA exposure induced oxidative stress and damage in multiple organs. Therefore, the present study was designed to investigate the adverse effects of dietary ZEA (1.1 to 3.2 mg/kg of diet) on oxidative stress and organ damage in postweaning gilts. A total of 20 gilts (Landrace × Yorkshire × Duroc) weaned at d 21 with an average BW of 10.36 ± 1.21 kg was used in the study. Gilts were housed in a temperature-controlled room, divided into 4 treatments, and fed a basal diet only (control) or basal diet supplemented with purified ZEA at a dietary concentration of 1 (ZEA1), 2 (ZEA2), or 3 (ZEA3) mg/kg of diet for 18 d ad libitum. The actual ZEA contents (analyzed) were 0, 1.1 ± 0.02, 2.0 ± 0.01, and 3.2 ± 0.02 mg/kg for control, ZEA1, ZEA2, and ZEA3, respectively. Gilts fed different amounts of dietary ZEA grew similarly with no difference (P > 0.05) in feed intake. Vulva size increased linearly over the 18 d of feeding in gilts fed diets containing 1.1 mg of ZEA/kg or greater (P < 0.001). Relative weight of genital organs, liver, and kidney increased linearly (P < 0.05) in a ZEA-dose-dependent manner. Serum aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, γ-glutamate transferase, urea, and creatinine (P < 0.05), and malondialdehyde concentrations in both serum and liver (P < 0.001) were also increased linearly in a ZEA-dose-dependent manner. However, spleen relative weight (P = 0.002) and activities of total superoxide dismutase and glutathione peroxidase (in both serum and liver (P < 0.05) were decreased linearly as dietary ZEA increased. Results showed that besides genital organs, the liver, kidney, and spleen may also be target tissues in young gilts fed diets containing 1.1 to 3.2 mg of ZEA/kg for 18 d. Increased key liver enzymes in the serum suggest progressive liver damage caused by feeding ZEA, and an increase in oxidative stress in gilts is another potential impact of ZEA toxicity in pigs.     

Changes in the spleen and liver of pregnant sows and full-term piglets after feeding diets naturally contaminated with deoxynivalenol and zearalenone

Wheat contaminated naturally with the Fusarium toxins deoxynivalenol (DON) and zearalenone (ZON) was fed to pregnant Landrace sows for 35days. On day 110, caesarean section was carried out, the offspring were killed immediately after birth, and their livers and spleens examined. At necropsy there were no macroscopic lesions observed in any organ of either sows or piglets. Histopathological evaluation of tissues from sows of the treated group revealed changes in liver and spleen tissues, whereas no significant changes were observed in these tissues in their piglets. Liver damage, as measured by prominent elevated transaminase activities, was not detected in the serum of the sows. In pregnant sows there were individual variations in sensitivity to the Fusarium toxins. In conclusion, it can be assumed that there are no adverse effects on the liver and spleen of full-term piglets when their mothers consumed diets containing up to 9570 and 358mug DON/ZON per kg diet.     

The efficacy of a modified aluminosilicate as a detoxifying agent in Fusarium toxin contaminated maize containing diets for piglets

Two feeding experiments with female weaned piglets were carried out applying a complete two by two factorial design to investigate the effects of the dietary inclusion of 500 g/kg Fusarium toxin contaminated maize (8.6 mg/kg deoxynivalenol (DON); 1.2 mg/kg zearalenone (ZON)) and of 4 g/kg aluminosilicate (AS) as a detoxifying agent. The resulting four diets were fed ad libitum to a total of 80 piglets (20 piglets per group, allotted to a total of 20 pens) covering a live weight range of 10.5 +/- 1.3 to 27.5 +/- 4.4 kg in experiment 1, and to a total of 48 piglets (12 piglets per group, allotted to 12 pens) covering a live weight range of 9.7 +/- 1.8 to 21.4 +/- 4.8 kg in experiment 2. The animals of experiment 1 were slaughtered on days 34-36 of feeding the experimental diets. The mycotoxin analyses revealed that the control maize also contained considerable concentrations of Fusarium toxins, but the differences in DON and ZON concentrations between control and contaminated diets were sufficiently high to demonstrate both dose-related toxin effects. Voluntary feed intake and live weight gain of the animals were significantly reduced by the inclusion of Fusarium toxin contaminated maize into the diets in both experiments, while a significantly decreased feed to gain ratio was found in experiment 1. Furthermore, the relative weight of the uterus, stomach and heart of the animals fed the contaminated maize containing diets were significantly increased. Serum albumin concentrations and the activity of GLDH were significantly reduced by the inclusion of the contaminated maize. The addition of AS to the Fusarium toxin contaminated diets did not prevent or alleviate any of the mentioned effects. Moreover, the feed intake tended to be decreased by this supplementation in both experiments, while a significantly decreased feed to gain ratio was indicated for this factor in experiment one as well. The serum concentration of albumin and the activities of ASAT and gammaGT were significantly increased if AS was present in the diets while serum concentration of cholesterol and alpha-tocopherol were decreased significantly or in tendency, respectively. The concentrations of retinol and retinyl esters in liver and serum were not altered by the treatments. The analysed concentrations of zearalenone (ZON) and its metabolites in the bile fluid clearly indicated the differences in dietary ZON concentrations and showed that AS was ineffective in preventing the absorption of the toxin from the gastrointestinal tract. Also, serum concentrations of DON reflected the DON intake prior to sampling. However, there were no differences between groups fed diets with or without AS which also suggests the inefficacy of the tested AS in preventing the DON absorption. The present investigations failed to demonstrate a detoxifying capacity of the tested additive and emphasize the general necessity for a critical verification of detoxifying agents in vivo.     

Effects of graded levels of Fusarium toxin contaminated maize in diets for female weaned piglets.

A dose response study was carried out with piglets to examine the effects of increasing amounts of Fusarium toxins in the diet on performance, clinical serum characteristics, organ weights and residues of zearalenone (ZON) and deoxynivalenol (DON) and their metabolites in body fluids and tissues. For this purpose, Fusarium toxin contaminated maize (1.2 mg ZON and 8.6 mg DON per kg maize) was incorporated into a maize based diet for piglets at 0, 6, 12.5, 25 and 50% at the expense of control maize. The experimental diets were tested on 100 female piglets allotted to 20 boxes (five animals per box) covering a body weight range of 12.4 +/- 2.2 kg to 32.5 +/- 5.6 kg. Voluntary feed intake and, consequently, body weight gain of the animals receiving the highest proportion of Fusarium toxin contaminated maize were significantly decreased while the feed conversion ratio was not affected by the treatment. The mean weight of the uterus related to the body weight of the animals of the same group was increased by almost 100% as compared to the control. For this group, significantly decreased values of total serum protein were determined, while the serum activity of the liver enzyme glutamate dehydrogenase and the serum concentration of the follicle stimulating hormone were decreased for all treatment groups receiving 6% contaminated maize or more in the diet. Serum concentrations of immuneglobulins were not consistently altered by the treatment. Corresponding to the dietary exposure, increasing concentrations of ZON and alpha-zearalenol were detected in the bile fluid, liver and in pooled urine samples. The metabolite beta-zearalenol was detected only in bile fluid. The total concentration of ZON plus its metabolites in bile fluid correlated well with the diet contamination (r = 0.844). DON was found in serum, bile fluid and pooled urine samples while de-epoxy-DON was detected only in urine. The serum concentration of DON correlated well with the respective toxin intake 3-4 h prior to slaughtering (r = 0.957). For all mentioned analyses of residues it has to be noted that toxin residues were detectable even if negligible concentrations were present in the diet.     

Effects of diets with cereal grains contaminated by graded levels of two Fusarium toxins on selected immunological and histological measurements in the spleen of gilts

Feeding experiments with diets containing Fusarium toxin-contaminated wheat were conducted to clarify the pathogenesis of immunological effects of Fusarium toxins to porcine spleen cells. Contaminated diets were fed to 36 Landrace prepubertal gilts for 35 d. Concentrations (as-fed basis) of the indicator toxins deoxynivalenol (DON) and zearalenone (ZON), respectively, were 210 and 4 (control--group I), 3,070 and 88 (group II), 6,100 and 235 (group III), and 9,570 and 358 microg/kg (group IV). No signs of hyperestrogenism or uterotrophic effects were observed because of dietary treatments. The feeding of mycotoxin-contaminated diets did not cause gross pathological findings in the spleens of animals. In vivo, no inhibitory effects were detected on concanavalin A-stimulation of blood lymphocytes; however, the proliferation rate of splenocytes was inhibited (P < 0.05) in pigs fed the diet with the highest DON/ZON concentration. With in vitro studies, lower proliferation rates of blood lymphocytes and splenocytes preexposed to DON were detected. Serum IgA concentrations of pigs in group II were increased (P < 0.05) compared with the baseline value before feeding the DON/ZON diet. The histopathological data indicated elevated (P < 0.05) iron staining in the red pulp of spleens in gilts from groups I to IV after 35 d of feeding. The presence of hemosiderin particles in the spleen sections was confirmed by transmission electron microscopic investigation. Together, the results provide evidence of spleen dysfunction (hemosiderosis) in the absence of clinical signs, especially in pigs fed higher concentrations (groups III and IV) of Fusarium toxin-contaminated wheat.     

不同水平玉米赤霉烯酮对断奶母仔猪血清酶、代谢产物和肠道形态的影响

本试验旨在研究不同水平玉米赤霉烯酮(ZEA)对断奶母仔猪血清酶、代谢产物和肠道形态的影响。选取28日龄平均体重为(14.01±0.86)kg、健康的三元杂交(杜×长×大)雌性断奶仔猪40头,随机分为4组,每组10头。对照组饲喂基础饲粮,试验1组、试验2组和试验3组在基础饲粮中分别添加0.5、1.0和1.5 mg/kg ZEA。预试期10 d,正试期35 d。结果表明:1)与对照组相比,各试验组的谷草转氨酶、碱性磷酸酶和乳酸脱氢酶活性显著升高(P0.05);试验2组的血清总胆固醇含量显著升高(P0.05);试验3组血清尿素氮和高密度脂蛋白(HDL)含量显著升高(P0.05),血清总蛋白含量则显著降低(P0.05)。2)与对照组相比,试验组十二指肠和空肠绒毛高度和隐窝深度都显著增大(P0.05)。试验1组和试验2组十二指肠绒毛高度/隐窝深度值显著提高(P0.05),空肠绒毛高度/隐窝深度值显著降低(P0.05),回肠绒毛高度和绒毛高度/隐窝深度值都显著升高(P0.05)。3)与对照组相比,试验组十二指肠绒毛高度明显增大且排列疏松无序,小肠腺数量减少,黏膜厚度变薄。4)与对照组相比,试验组空肠绒毛高度增大,小肠腺数量减少,并且试验2组和试验3组空肠上皮脱落固有层裸露。5)与对照组相比,试验1组和试验2组回肠绒毛高度增大且黏膜下层内弥散淋巴细胞增多。由此可见,饲粮中添加ZEA(0.5~1.5 mg/kg)改变了断奶母仔猪的肝脏代谢和肠道的形态结构,进而影响断奶母仔猪的健康生长。     

On the effects of a chronic deoxynivalenol intoxication on performance, haematological and serum parameters of pigs when diets are offered either for ad libitum consumption or fed restrictively

Wheat infected naturally with Fusarium, contaminated mainly with deoxynivalenol (DON) (16.6 mg DON/kg), was added to a total constant wheat content of 400 g/kg diet. To distinguish between differences in feed intake and specific effects of the DON contaminated diet, control and DON contaminated feed was administered for 11 weeks under ad libitum and restrictive feeding conditions to 48 pigs of both sexes, which were randomly divided into four groups (n = 12 per group). Feed intake was 2.90 kg/day, live weight gain 987 g/day and feed to gain ratio 2.77 kg/kg for the ad libitum fed control group. The group fed DON contaminated wheat ad libitum significantly consumed 15% less feed and gained 13% less live weight, while the feed to gain ratio was unaffected. Moreover, it was concluded that the lower growth performance by DON contaminated feed resulted mainly from the lower voluntary feed intake, because there were no differences in live weight gain between the groups with the restrictive feeding regimen. On the contrary, metabolizable energy, nitrogen retention digestibility of organic matter, crude protein, crude fat and crude fibre were significantly increased by 3, 10, 3, 6, 9 and 20% in the DON group respectively. Animals fed DON contaminated diets needed more time to consume the restrictive ration than the control group. For example in the first hour after feeding 85% of the control pigs had consumed all feed, but only 39% of the DON group had. There were only few differences in haematological and serum parameters, which were characterized by a high variation between individuals. DON and IgA concentrations in serum were significantly influenced by DON exposure.     

玉米赤霉烯酮对断奶小母猪卵巢指数及孕激素受体分布和表达的影响

本试验旨在研究不同水平玉米赤霉烯酮(ZEA)污染饲粮对断奶小母猪卵巢指数及孕激素受体的阳性分布和mRNA相对表达量的影响。选择40头35~38日龄健康三元杂交(杜×长×大)断奶小母猪,按平均体重[(14.01±0.86)kg]随机分为4个组,采用单笼饲养。对照组饲喂基础饲粮,试验组分别在基础饲粮中添加0.5、1.0和1.5 mg/kg的ZEA,4个组ZEA的测定值分别为0、(0.52±0.07)mg/kg、(1.04±0.03)mg/kg和(1.51±0.13)mg/kg。试验期35 d。结果表明:随着饲粮ZEA水平的升高,断奶小母猪卵巢指数呈一次线性升高(P0.01);1.0 mg/kg ZEA组的卵巢指数显著高于1.5 mg/kg ZEA组(P0.05),1.5 mg/kg ZEA组的卵巢指数显著高于0.5 mg/kg ZEA组和对照组(P0.05)。随着饲粮ZEA水平的升高,断奶小母猪卵巢孕激素受体累积光密度(IOD)和mRNA相对表达量均呈一次线性升高(P0.01);1.5 mg/kg ZEA组的孕激素受体IOD和mRNA相对表达量显著高于1.0 mg/kg ZEA组(P0.05),1.0 mg/kg ZEA组又显著高于0.5 mg/kg ZEA组和对照组(P0.05)。免疫组化结果显示断奶小母猪卵巢中孕激素受体免疫阳性物质主要分布于原始卵泡和生长卵泡的卵母细胞及颗粒细胞、卵泡膜细胞及血管壁细胞。随着饲粮ZEA水平的升高和卵泡闭锁程度的增加,免疫阳性反应明显增强,但卵巢内孕激素受体免疫阳性物质的分布位置没有因ZEA的水平发生明显改变。由此可见,ZEA(1.0~1.5 mg/kg)可以通过调控断奶小母猪卵巢中孕激素受体的高水平表达,使孕激素受体的水平超出正向调节卵泡生长的限值,从而促使卵泡闭锁,降低卵巢指数,改变卵巢发育,进而影响断奶小母猪生殖系统的健康。     

大豆异黄酮抗霉变饲料对肉鸡的影响及机制

将150只8日龄艾维茵肉仔鸡随机分成5个处理组,每个处理组5个重复,每次重复6只鸡。处理1组饲喂正常饲粮(阳性对照),处理2组为10%霉变玉米替代处理1组中正常玉米(阴性对照),处理3、4、5组分别在处理2组基础上添加100、200 mg/kg的大豆异黄酮和0.05%的膨润土。结果显示,与阳性对照组比较,处理2组显著地降低了肉鸡的采食量、日增重,增加了料肉比(P<0.05);显著地提高了血清中AST、ALT、AKP和LDH的浓度(P<0.05);同时降低了肝脏和血清中GSH-PX、SOD的活性(P<0.05)。大豆异黄酮和膨润土的添加显著地提高了肉鸡采食量、日增重(P<0.05),降低了料肉比(P<0.05);同时降低了血清中AST、ALT、AKP和LDH的浓度(P<0.05);大豆异黄酮的添加还显著地提高了肝脏和血清中GSH-PX、SOD的活性(P<0.05)。结果表明,大豆异黄酮显著地抑制了霉菌毒素对肉鸡肝功能和生长性能的影响。     

Effects of excessive selenium supplementation to diet contaminated with deoxynivalenol on blood phagocytic activity and antioxidative status of broilers

This study examined the effects of excessive dietary supplementation with organic selenium on phagocytic activity and antioxidative status of chickens for fattening fed diet contaminated with deoxynivalenol (DON). Sixty chickens of Ross 308 hybrids were at day of hatching divided into four groups with 15 birds in each. The background DON dietary levels in both negative and positive control groups were 0.2 mg/kg. The complete feed for positive control group was supplemented with Se dose 1 mg/kg in the form of Se-yeast. Group 3 was fed diet with DON level 3 mg/kg while diet for group 4 combined DON level 3 mg/kg with a excessive supplement of Se-yeast (Se dose 1 mg/kg). After 6 weeks of dietary intake, six randomly-chosen chickens from each group were sampled. Feeding of contaminated diet resulted in significantly reduced blood phagocytic activity (19.5 ± 1.1% in the negative control vs. 12.8 ± 0.8% in the DON-treated group, p < 0.05). Se-yeast supplemented to the DON contaminated diet prevented suppression of phagocytic activity. Dietary intake of DON at levels 3 mg/kg did not influence the plasma α-tocopherol level while excessive dietary Se dose reduced it in both Se supplemented groups. Neither the birds of DON-treated group nor the birds from group 4 with DON and Se-yeast showed any response in plasma γ-glutamyltransferase (GGT) activity. Subtoxic dietary level of DON significantly increased the activity of glutathione peroxidase (GPx) in the duodenal mucosa, while additional Se supplementation prevented such a response to mycotoxin. On the other hand, both Se supplemented groups showed significantly elevated GPx activities in blood, liver and kidney, (p < 0.05). The results suggest a potential ability of excessive supplementation of organic selenium to prevent the blood phagocytic activity suppression and changes in GPx activity in duodenal tissue induced in broilers by subtoxic dietary levels of DON.     

The effects of naturally deoxynivalenol-contaminated oats on the clinical condition,blood parameters,performance and carcass composition of growing pigs

A feeding trial with naturally deoxynivalenol (DON)-contaminated oats included in feed mixtures at graded levels was conducted in growing pigs. The DON concentrations were 0, 0.7, 1.7, and 3.5 mg/kg of complete feed mixture givenad libitum to different groups. The data recorded were feed consumption, body weight gain, slaughter weight, biochemical and haematological data including serum immunoglobulin A, clinical condition and post-mortem pathology including histopathology.Significantly decreasing body weight gain throughout the experimental period, decreased slaughter weight and reduced feed utilization efficiency were observed for the group fed a diet containing 3.5 mg/kg of DON. At the same DON concentration, there were increased liver weights and decreased concentrations of serum protein and albumin, and a temporary fall in packed blood cell volume, serum calcium and serum phosphorus. For the groups fed diets containing 1.7 and 3.5 mg/kg of DON, a statistically significant, dose-related decrease in daily feed consumption was observed. No other effects on haematological, biochemical or immunological parameters were recorded. The carcass quality was not affected in any group.It was concluded that significant effects in growing pigs may be observed at a dietary DON concentration of 1.7 mg/kg, originating from naturally contaminated oats included in a diet that was otherwise adequate and contained only minor traces of other mycotoxins.Abbreviations ALAT alanine aminotransferase - ASAT aspartate aminotransferase - CFU colony-forming units - DON deoxynivalenol - 3-ac-DON 3-acetyl-deoxynivalenol - F.U. feed unit - FUS-X fusarenon-X - HPLC high-pressure liquid chromatography - IgA immunoglobulin A - NFSA nutrient-free sporulation agar - NIV nivalenol - PDA potato dextrose agar     

Effects of Fusarium toxins on growth, humoral immune response and internal organs in weaner pigs, and the efficacy of apple pomace as an antidote

A feeding trial using 220 weaner pigs which comprised two experimental series was conducted to investigate the effects of diets contaminated with the Fusarium toxins deoxynivalenol (DON) and zearalenone (ZON) and to test the hypothesis that apple pomace acts as an antidote to these mycotoxins. Two diets without contaminated wheat, containing either no pomace or 8% pomace, and two diets with naturally contaminated wheat (3.2 mg DON and 0.06 mg ZON, and 2.1 mg DON and 0.25 mg ZON per kg diet in series 1 and 2 respectively), containing either no pomace or 8% pomace were fed ad libitum for 5 weeks. Mycotoxin exposure lowered feed intake (p < 0.01) and growth (p = 0.05), and tended to decrease the energy conversion ratio (p = 0.06). Although the intake of apple pomace did not increase feed intake, it increased the growth rate (p = 0.04), mainly by restoring growth in the presence of mycotoxins (p = 0.08 for the interaction mycotoxin x pomace). In the first experimental series, the animals were immunized with a parvovirus vaccine. The percentage of seroconverting animals did not differ between the treatments (p = 0.56), which indicates that DON did not affect the humoral immune response. In the second experimental series, female piglets fed the contaminated diets had heavier uteri than piglets fed the uncontaminated diets (p < 0.01), regardless of pomace supplementation. The results show that pomace may alleviate the negative effect of DON on growth but does not counteract the hormonal effects of ZON.     

玉米赤霉烯酮与脱氧雪腐镰刀菌烯醇联合染毒对雄性小鼠生殖毒性的影响及茶多酚的缓解作用

本试验旨在研究茶多酚对玉米赤霉烯酮(ZEN)与脱氧雪腐镰刀菌烯醇(DON)联合染毒小鼠生殖毒性损伤的缓解作用。选取8周龄雄性昆明小鼠75只[体重(40±5)g],随机分成5组,每组分别灌服生理盐水(对照组)、200 mg/kg茶多酚(Ⅰ组)、1 mg/kg ZEN+0.5 mg/kg DON(Ⅱ组)、100 mg/kg茶多酚+1 mg/kg ZEN+0.5 mg/kg DON(Ⅲ组)和200 mg/kg茶多酚+1 mg/kg ZEN+0.5 mg/kg DON(Ⅳ组),每组15只。试验期28 d。在试验第1、14、28天,从每组随机抽取5只小鼠称重采样,检测小鼠精子质量、睾丸脏器系数、睾丸组织标志酶活性、血清性激素含量及睾丸组织氧化与抗氧化指标,并制作睾丸组织切片。结果表明:1)与对照组相比,Ⅱ组小鼠睾丸脏器系数、精子活率及数量、血清性激素含量显著降低(P<0.05),睾丸组织碱性磷酸酶(AKP)、乳酸脱氢酶(LDH)、γ-谷氨酰转移酶(γ-GGT)、过氧化氢酶(CAT)、超氧化物歧化酶(SOD)及谷胱甘肽过氧化物酶(GSH-Px)活性显著降低(P<0.05);精子畸形率、血清丙二醛(MAD)含量显著上升(P<0.05)。添加茶多酚后,小鼠的睾丸脏器系数、精子活率及数量、血清性激素含量、睾丸组织AKP、LDH、γ-GGT、CAT、SOD及GSH-Px活性显著上升(P<0.05),精子畸形率、血清MAD含量显著降低(P<0.05)。随着时间的推移,与第1天相比,Ⅰ组小鼠睾丸组织GSH-Px活性显著升高(P<0.05),Ⅱ组小鼠睾丸脏器系数、精子质量、睾丸组织标志酶活性、血清性激素含量、睾丸组织氧化与抗氧化指标均发生显著变化(P<0.05),Ⅲ组小鼠睾丸组织CAT及GSH-Px活性显著降低(P<0.05),Ⅳ组小鼠睾丸组织CAT活性显著降低(P<0.05)。2)睾丸组织病理切片显示染毒组小鼠睾丸生精小管基膜不完整,细胞排列紊乱,数量减少,体积缩小,细胞之间空泡化,管腔内精子数量减少,经茶多酚保护后得到改善。综上,茶多酚能有效改善ZEN与DON联合染毒小鼠精子质量与睾丸组织内标志酶活性,提高血清性激素含量及睾丸组织抗氧化功能,显著降低生殖毒性。     

Effects of feeding grains naturally contaminated with Fusarium mycotoxins with and without a polymeric glucomannan mycotoxin adsorbent on reproductive performance and serum chemistry of pregnant gilts

Contamination of animal feedstuffs with Fusarium mycotoxins can cause reduced feed intake and hyperaminoacidemia resulting from reduced hepatic protein synthesis. The current study investigated the effects of feeding grains naturally contaminated with Fusarium mycotoxins on reproductive performance, serum chemistry, ADFI, and ADG of gilts, and tested the ability of a polymeric glucomannan mycotoxin adsorbent (GMA) to reduce or eliminate the effects of the contaminated feeds. Thirty-six Yorkshire gilts were fed 3 diets (n = 12 gilts/diet) from 91 +/- 3 d of gestation until farrowing. Diets included 1) control, 2) contaminated grains, and 3) contaminated grains + 0.2% GMA. Diets contaminated with Fusarium mycotoxins did not affect ADFI (P = 0.24), but ADG (P = 0.029) and G:F (P = 0.047) were reduced. Serum concentrations of beta-hydroxybutyrate, haptoglobin, protein, albumin, globulin, urea, glucose, cholesterol, Ca, Na, Mg, P, K, and Cl, and hepatic enzyme activities were not affected by diet. The frequency of stillborn piglets was greater (P = 0.03) for gilts fed contaminated grains compared with that of gilts fed contaminated grains + GMA. The feeding of contaminated grains + GMA also increased (P = 0.026) the percentage of pigs born alive compared with gilts fed the contaminated diets. In conclusion, feeding gilts diets that are naturally contaminated with Fusarium mycotoxins can increase the incidence of stillborn piglets and this effect can be reduced by dietary supplementation with GMA.     

玉米赤霉烯酮对母猪繁殖性能和胎盘免疫相关基因表达量的影响

本试验旨在研究饲粮中添加玉米赤霉烯酮(ZEN)对母猪繁殖性能和胎盘免疫相关基因表达量的影响。选择胎次相近、体重200 kg、妊娠第30天的长×大二元杂交母猪40头,随机分为2组,每组20个重复,每个重复1头。对照组饲喂基础饲粮,试验组饲粮在基础饲粮中添加1.5 mg/kg的ZEN。试验期74 d。结果表明,与对照组相比:1)饲粮中添加ZEN显著提高了妊娠期母猪死胎数和弱仔猪数(P0.05),显著降低了母猪总产仔数(P0.05);2)饲粮中添加ZEN显著提高了妊娠期母猪血清孕酮含量(P0.05);3)饲粮中添加ZEN显著提高了妊娠期母猪胎盘中Toll样受体-2(TLR-2)和孕酮受体(PGR)基因表达量(P0.05)。由此可见,母猪妊娠期饲粮中添加1.5 mg/kg ZEN可显著降低母猪总产仔数,并显著提高死胎数和弱仔猪数。饲粮中低水平的ZEN对母猪繁殖性能仍产生不利影响。     

壳聚糖对断奶仔猪生长性能、粪便评分及血清激素和T淋巴细胞亚群的影响

本试验旨在研究壳聚糖对断奶仔猪生长性能、粪便评分及血清激素和T淋巴细胞亚群的影响。选取28日龄断奶的杜×大×长三元杂交仔猪60头,随机分为5组(每组12头):对照组饲喂基础饲粮,试验组分别饲喂在基础饲粮中添加250、500、1 000和2 000 mg/kg壳聚糖的试验饲粮。试验期14 d。结果表明:1)饲粮添加250~2 000 mg/kg壳聚糖显著提高断奶仔猪的平均日增重(ADG)(P0.05),显著降低料重比(F/G)(P0.05);2)饲粮添加250~2 000 mg/kg壳聚糖显著降低试验第11天断奶仔猪的粪便评分(P0.05);3)饲粮添加适宜剂量的壳聚糖显著提高断奶仔猪的血清促生长激素释放激素(GHRH)(250~2 000 mg/kg)、生长激素(GH)(500~1 000 mg/kg)和瘦素(LP)(2 000 mg/kg)的浓度(P0.05),显著降低血清促肾上腺皮质激素释放激素(CRH)(250~2 000 mg/kg)、促肾上腺皮质激素(ACTH)(500~1 000 mg/kg)、皮质醇(COR)(250~2 000 mg/kg)和可溶性CD8(sCD8)(500~2 000 mg/kg)的浓度(P0.05)。由此可见,饲粮中添加适宜剂量的壳聚糖能够促进断奶仔猪的生长,降低腹泻,缓解断奶应激。     

Subacute effects of moderate feed loads of isolated Fusarium toxin deoxynivalenol on selected parameters of metabolism in weaned growing piglets

In 36 female weaned piglets, the effect of different dosages (0, 300, 600 and 1200 microg/kg feed) of isolated, pure Fusarium toxin deoxynivalenol (DON) was examined during a period of 8 weeks. Standardised trial conditions were provided. Pigs were fed restrictively to allow a complete feed intake of all animals. Parameters of liver integrity, haematological data and blood concentrations of some selected metabolic components of energy and protein metabolism were examined weekly. Enzyme aspartate aminotransferase was affected subclinically by age and significantly by dosage, which was proved by Wald F-test. Some additional enzymes, for instance alanine aminotransferase, gamma glutamyl transferase, glutamate dehydrogenase and sorbit dehydrogenase, showed no clear systematic effect. Urea and glucose in the blood were inter-related. Depending on DON load with increasing glucose concentrations, the urea level declined. Albumin and total protein in serum showed no significant DON-related effect. Haemoglobin in blood was found to be significantly affected by DON, which was proved by the Wald F-test, where the effect was more pronounced with 600 microg DON/kg diet compared to 1 200 microg DON/kg. An obvious DON-related affection of liver, N-metabolism and stimulation of haematopoiesis depending on dosage and time is discussed.