The influence of ergot-contaminated feed on growth and slaughtering performance, nutrient digestibility and carry over of ergot alkaloids in growing-finishing pigs

Diets containing 0, 1 and 10 g ergot (Claviceps purpurea) per kg, corresponding to mean total alkaloid contents of 0.05, 0.60 and 4.66 mg/kg (sums of ergometrine, ergotamine, ergocornine, alpha-ergocryptine, ergocristine, ergosine and their -inine isomers analysed by a HPLC-method), were each fed ad libitum to 12 pigs in the BW range of 30-115 kg to study the effect of ergot-contaminated feed on growth and slaughtering performance and the carry over of ergot alkaloids. Additionally, balance trials were conducted to investigate the digestibility of nutrients. Tendencies towards reduced feed intake and BWG were observed at a feeding level of 4.66 mg total alkaloids per kg diet. Typical symptoms of ergot poisoning were not observed. Heart and spleen weights showed significant linear increases. Differences in carcass quality due to dietary treatment were not detected. No genuine ergot alkaloids were found in physiological samples. The balance trials demonstrated a significantly decreased protein digestibility for the most highly supplemented diet.     

Comparative studies on the effect of ergot contaminated feed on performance and health of piglets and chickens

Two dose response trials were conducted with piglets and chickens to study the effects of increasing amounts of ergot (Claviceps purpurea) with a defined alkaloid content and pattern on performance, biochemical serum characteristics and organ weights (of chickens). The ergot was mixed into the cereal-soybean meal based diets at levels of 0, 0.5, 1, 2 and 4?g/kg. The total alkaloid content of the ergot was analysed to be 2775?mg/kg and showed the following composition: ergometrine 8.1%, ergotamine 5.4%, ergocornine 3.2%, α-ergocryptine 1.9%, ergocristine 14.9% and residue 66.5%. Each treatment was tested with eight castrated male and eight female piglets over a period of 35 days (8?kg initial live weight) and 28 male chickens for 21 days (43?g initial live weight). Cumulative daily dry matter intake and live weight gain [g/d] were 595, 535, 560, 577 and 490 and 413, 399, 420, 443 and 347 for the piglets fed the unsupplemented control diet and the diets containing 0.5, 1, 2 and 4?g ergot per kg, respectively. Feed intake and live weight gain of the piglets fed the highest ergot supplemented diet were significantly decreased. Serum aspartate aminotransferase activity of the 4?g ergot treatment was significantly increased. Also serum albumin concentrations showed significant linear alterations. Serum activities of glutamate dehydrogenase, γ-glutamyltransferase, total protein and porcine growth hormone were not significantly influenced by dietary treatment. The experiment with chickens demonstrated no significant effects on performance due to dietary ergot exposure. The serum activities of glutamate dehydrogenase and alanine aminotransferase were not significantly influenced by dietary treatment while serum activities of γ-glutamyltransferase and aspartate aminotransferase and the concentrations of albumin and total bilirubin were significantly affected. Heart weights showed a significant linear decrease due to ergot feeding. According to these results, piglets seemed to react more sensitively on the occurrence of ergot in the diet as compared to chickens. The critical level of total ergot alkaloids for piglets seemed to be in the range from 5.6?mg to 11.1?mg/kg diet for the present study. Ergot effects on signs of inflammation in the proximal duodenum occurred in chickens fed diets containing 2.8?mg and 11.1?mg total ergot alkaloids/kg although live performance remained unaffected. Further studies are necessary to define the critical level of ergot alkaloids in dependence on alkaloid pattern.     

Effects of different levels of ergot in concentrates on the growing and slaughtering performance of bulls and on carry-over into edible tissue

Abstract

The aim of the present study was to examine long-term effects of low levels of ergot alkaloids on growing bulls. Natural grown ergot with a mean total alkaloid concentrations of 633 mg/kg, and ergotamine (25%), ergocristine (15%) and ergosine (13%) as the most prominent alkaloids, was used. In a dose-response study 38 Holstein Friesian bulls were fed with three different doses of this ergot (0, 0.45 and 2.25 g/kg concentrate corresponding to an average total alkaloid concentration of the daily ration of 0, 69 and 421 µg/kg DM) over a period of approximately 230 days. Live weight, feed intake and health condition were monitored over the entire test period. The bulls were slaughtered at a live weight of approximately 550 kg. Carcass composition and quality were recorded and samples of liver, muscle, kidneys, fat, bile, urine and blood were analysed for ergot alkaloids. Liver enzyme activities and total bilirubin were measured in the blood. Statistically, no significant differences were detectable between the three feeding groups. Mean live weight gain over all groups was 1.41 kg/d with a mean dry matter intake of 7.35 kg/d. No carry over into tissues could be proved out of the experiment. To derive a no-effect level for beef cattle further research including higher ergot doses will be necessary.     

Comparative studies on the effect of ergot contaminated feed on performance and health of piglets and chickens

Two dose response trials were conducted with piglets and chickens to study the effects of increasing amounts of ergot (Claviceps purpurea) with a defined alkaloid content and pattern on performance, biochemical serum characteristics and organ weights (of chickens). The ergot was mixed into the cereal-soybean meal based diets at levels of 0, 0.5, 1, 2 and 4 g/kg. The total alkaloid content of the ergot was analysed to be 2775 mg/kg and showed the following composition: ergometrine 8.1%, ergotamine 5.4%, ergocomine 3.2%, alpha-ergocryptine 1.9%, ergocristine 14.9% and residue 66.5%. Each treatment was tested with eight castrated male and eight female piglets over a period of 35 days (8 kg initial live weight) and 28 male chickens for 21 days (43 g initial live weight). Cumulative daily dry matter intake and live weight gain [g/d] were 595, 535, 560, 577 and 490 and 413, 399, 420, 443 and 347 for the piglets fed the unsupplemented control diet and the diets containing 0.5, 1, 2 and 4 g ergot per kg, respectively. Feed intake and live weight gain of the piglets fed the highest ergot supplemented diet were significantly decreased. Serum aspartate aminotransferase activity of the 4 g ergot treatment was significantly increased. Also serum albumin concentrations showed significant linear alterations. Serum activities of glutamate dehydrogenase, gamma-glutamyltransferase, total protein and porcine growth hormone were not significantly influenced by dietary treatment. The experiment with chickens demonstrated no significant effects on performance due to dietary ergot exposure. The serum activities of glutamate dehydrogenase and alanine aminotransferase were not significantly influenced by dietary treatment while serum activities of gamma-glutamyltransferase and aspartate aminotransferase and the concentrations of albumin and total bilirubin were significantly affected. Heart weights showed a significant linear decrease due to ergot feeding. According to these results, piglets seemed to react more sensitively on the occurrence of ergot in the diet as compared to chickens. The critical level of total ergot alkaloids for piglets seemed to be in the range from 5.6 mg to 11.1 mg/kg diet for the present study. Ergot effects on signs of inflammation in the proximal duodenum occurred in chickens fed diets containing 2.8 mg and 11.1 mg total ergot alkaloids/kg although live performance remained unaffected. Further studies are necessary to define the critical level of ergot alkaloids in dependence on alkaloid pattern.     

Effects of different levels of ergot in concentrate on the health and performance of male calves

A number of studies dealing with the effects of ergot and ergot alkaloids on the health and performance of poultry and pigs were reported in the past, but only a few studies and field reports are available for ruminants. Therefore, a dose-response study was carried out with calves since young animals are considered to be especially sensitive to ergot. A total of 35 male Holstein calves were randomly assigned to three feeding groups after one month of feeding milk replacer. The mean initial live weight of the calves was 49.4±5.7 kg. One control group was fed an ergot-free concentrate (n=12), one group an ergot proportion of 1000 mg/kg in the concentrate (n=ll), and another group was fed a concentrate containing 5000 mg/kg ergot (n=12). Hay, grass silage and water were available forad libitum consumption, whereas the daily concentrate portion was restricted to 2 kg. Live weight, health parameters and feed intake were monitored over the experimental period of 84 days. In addition, blood samples were taken from theVena jugularis at the beginning and at the end of the experiment and analysed for ergot alkaloids and liver parameters. Total dry matter intake, live weight gain and feed-to-gain ratio were not significantly influenced by increasing ergot proportions when the whole experimental period was considered, although there was a trend for an ergot-related decrease in concentrate intake during the first 6 weeks of the experiment. After this period of time, it seemed that calves got used to the presence of ergot in the concentrate and were able to adjust their intake to the level of the control group. Moreover, health and liver parameters, such as total bilirubin, aspartate aminotransferase, glutamate dehydrogenase, gamma-glutamyl transpeptidase and creatine kinase in the serum were not significantly influenced by dietary treatments. Concentrations of the individual ergot alkaloids in serum were lower than the detection limits of the applied HPLC-method. In conclusion, it can be assumed that an ergot contamination of the concentrate up to 5000 mg/kg resulted in a transient depression of concentrate intake by the calves. However, no significant effects on health and performance could be detected when the entire test period of 84 days was considered. Presented at the 28^th Mykotoxin-Workshop, Bydgoszcz, Poland, May 29–31, 2006     

Dietary ergot alkaloids as a possible cause of tail necrosis in rabbits

This study describes the association between tail necrosis in rabbits and mycotoxins in rabbit feed. Clinical cases of tail necrosis were observed in 14 out of 103 rabbits kept in an outdoor group housing, fed with hay and a commercial pelleted feed. The observed clinical symptoms, alopecia, erosions, crusts and necrosis were restricted to the tail area and exclusively occurred in young rabbits aged 113?±?20 days. Dermatological examination suggested that ischemia had caused necrosis. Analysis of blood samples showed an elevated level of creatine kinase. No weight loss occurred in affected rabbits. Trauma caused by injuries or technopathic lesions was also excluded. Histopathologically, the lesions were characterized by acute muscle fibre degeneration and chronic active dermatitis with granulation tissue formation. Necropsy of one rabbit revealed hepatocellular degeneration and necrosis as remarkable findings. Feed analysis for ergot alkaloids by enzyme immunoassays yielded a mean and maximum ergot alkaloid content of 410?±?250 μg/kg and 1,700 μg/kg, respectively. Faeces of affected rabbits contained ergot alkaloids at levels up to 200 μg/kg. The mean and maximum dietary intake of total ergot alkaloids were 17 and 71 μg/kg bodyweight, respectively. Fusarium toxins (trichothecenes, zearalenone, fumonisins) were also found in the feed, but at levels which did not explain the observed effects. The results indicate that ergot alkaloids may have been the cause of tail necrosis, which is supported by literature data showing that rabbits are especially sensitive towards these toxins.     

The impacts of Macleaya cordata extract and naringin inclusion in post-weaning piglet diets on performance,nutrient digestibility and intestinal histomorphology

The current study investigated the impacts of supplementation of post-weaning piglet diets with Macleaya cordata extract (MCE) and naringin (NAR) on performance, nutrient digestibility and intestinal histomorphology. Post-weaning crossbred piglets (28 males and 28 females; age at weaning 25 d) were randomly allotted to 28 pens. The experiment consisted of a control and three treatment groups (MCE60, MCE120 and NAR). For diets MCE60 and MCE120, the control diet was supplemented with 60 and 120 mg Sangrovit® Extra (a standardised premixture of MCE) per kg diet, respectively. Group NAR received 50 mg pure NAR per kg diet. The experiment lasted 42 d (d 25 – 66 of age). At d 66, apparent pre-caecal digestibility (APD) of nutrients was determined and histomorphological changes in mid-jejunum were evaluated. Feeding diets MCE120 and NAR improved body weight gain and feed conversion ratio of piglets. After feeding diets MCE120 and NAR, the APD of phosphorus and different single and total amino acids were greater than after feeding the control diet. The present data demonstrated that supplementation of post-weaning piglet diets with 120 mg MCE or 50 mg NAR per kg diet could improve growth performance and nutrient digestibility and had no impact on histomorphological variables in the jejunum. These findings indicate the potential of these products to be used as growth promoters in pig nutrition.     

Effects of deoxynivalenol (DON) on growth performance, nutrient digestibility and DON metabolism in pigs

Wheat infected naturally withFusarium, contaminated mainly with 18.53 mg DON per kg, was added to a total constant wheat proportion of 400g/kg diet. Control and DON contaminated feed was fed for 11 weeks underad libitum and restrictive feeding conditions to 48 pigs of both sexes, which were randomly divided into 4 groups. Effects on performance (live weight range between 26 and 100kg), duration of feed intake and blood parameters were investigated. Parallel to this study, a balance study was carried out to examine the effects on nutrient digestibility and DON metabolism. The group fed the DON contaminated rationad libitum consumed 15% less feed and gained 14% less live weight compared to thead libitum control group, while the feed to gain ratio was unaffected. Under restrictive feeding conditions (DON and control) pigs exhibited 33%, 25% and 10% lower feed consumption, live weight gain and feed to gain ratio, respectively, than the control group fedad libitum. Metabolizability of energy, digestibility of organic matter, crude protein, crude fat and N-retention were significantly increased by 4, 3, 6, 11 and 10%, respectively, in the DON group of the restrictively fed pigs. In average up to 43.2% of the ingested DON, as the parent toxin in both groups, was eliminated with the urine and up to 3.0% with faeces. DON fed animals needed more time to consume the restrictive ration than the control group. Presented at the 26^th Mykotoxin-Workshop in Herrsching, Germany, May 17–19, 2004. Financial support Deutsone Forschungsgemeingschaft     

Effect of administration of anaerobic fungi isolated from cattle and wild blue bull ( Boselaphus tragocamelus ) on growth rate and fibre utilization in buffalo calves

Abstract

Fifteen Murrah buffalo calves (age about 10 months, 163 – 176 kg BW) were divided into three groups. Group I (Control) was fed a complete feed mixture consisted of 50% wheat straw and 50% concentrate mixture (contained per kg: maize 330 g, groundnut cake 210 g, mustard cake 120 g, wheat bran 200 g, de-oiled rice bran 110 g, mineral mixture 20 g and common salt 10 g) along with 2 kg green oats per animal and day to meet the vitamin A requirements. Calves of Groups II and III were fed with the Control diet supplemented with Orpinomyces sp. C-14 and Piromyces sp. WNG-12 cultures, respectively. The digestibility of DM was significantly highest with Piromyces sp. WNG-12 in Group III (62.2%) followed by Orpinomyces sp. C-14 in Group II (60.3%), and Control (53.5%). A similar pattern of increase in digestibility of crude protein and cell-wall contents was observed in treatment groups. The digestible energy in terms of percent total digestible nutrients was also significantly enhanced in Groups II (56.6%) and III (59.9%) when compared to Control (49.2%). The rumen fermentation parameters such as pH and NH₃-N were found to be lower, whereas total nitrogen, tricarboxylic acid precipitable-nitrogen, total volatile fatty acids and zoospore counts per millilitre of rumen liquor were significantly higher in fungal administered groups. After administration of fungal cultures, improvements of animal growth rate (i.e. body weight gain) and feed efficiency were also observed.     

Effects of folic acid on growth performance,ruminal fermentation,nutrient digestibility and urinary excretion of purine derivatives in post-weaned dairy calves

This study evaluated the effects of folic acid (FA) supplementation on growth performance, ruminal fermentation, nutrient digestibility and urinary purine derivatives (PD) excretion in dairy calves. Forty-eight Chinese Holstein male dairy calves at 60 ± 3.2 d of age and 89 ± 5.9 kg body weight (mean ± standard error) were assigned to one of four groups in a randomised block design. Calves in control group were fed basal diet, calves in low FA, medium FA and high FA groups with 3.6, 7.2 and 10.8 mg FA per kg basal diet, respectively. The dietary corn silage to concentrate ratio was 50:50 (dry matter [DM] basis). DM intake and average daily gain (ADG) quadratically increased, and feed conversion ratio quadratically decreased with increasing FA supplementation. Ruminal pH linearly decreased, whereas total volatile fatty acids quadratically increased. The unchanged acetate-to-propionate ratio was due to the similar change in acetate and propionate concentration. Ammonia N content quadratically decreased. Digestibility of DM, organic matter, crude protein, ether extract, neutral detergent fibre and acid detergent fibre linearly increased. Activities of carboxymethyl cellulase, cellobiase, xylanase and pectinase linearly increased, but α-amylase and protease quadratically increased. Abundance of Ruminococcus albus, Ruminococcus flavefaciens and Fibrobacter succinogenes linearly increased, but Butyrivibrio fibrisolvens and Prevotella ruminicola quadratically increased. Urinary total PD excretion quadratically increased. The results indicated that FA supplementation increased ADG, ruminal fermentation and nutrient digestibility with promoted ruminal microbial growth and enzyme activity, and the optimum dose was 7.2 mg FA per kg basal diet for calves.     

Effects of different levels of ergot in concentrates on the growing and slaughtering performance of bulls and on carry-over into edible tissue

The aim of the present study was to examine long-term effects of low levels of ergot alkaloids on growing bulls. Natural grown ergot with a mean total alkaloid concentrations of 633 mg/kg, and ergotamine (25%), ergocristine (15%) and ergosine (13%) as the most prominent alkaloids, was used. In a dose-response study 38 Holstein Friesian bulls were fed with three different doses of this ergot (0, 0.45 and 2.25 g/kg concentrate corresponding to an average total alkaloid concentration of the daily ration of 0, 69 and 421 microg/kg DM) over a period of approximately 230 days. Live weight, feed intake and health condition were monitored over the entire test period. The bulls were slaughtered at a live weight of approximately 550 kg. Carcass composition and quality were recorded and samples of liver, muscle, kidneys, fat, bile, urine and blood were analysed for ergot alkaloids. Liver enzyme activities and total bilirubin were measured in the blood. Statistically, no significant differences were detectable between the three feeding groups. Mean live weight gain over all groups was 1.41 kg/d with a mean dry matter intake of 7.35 kg/d. No carry over into tissues could be proved out of the experiment. To derive a no-effect level for beef cattle further research including higher ergot doses will be necessary.     

日粮添加褐藻糖胶对断奶仔猪抗炎能力和肠道微生物多样性的影响

【目的】本试验旨在研究日粮添加海带提取物褐藻糖胶对断奶仔猪生长性能、营养物质消化率、机体免疫力和肠道微生物多样性的影响。【方法】试验选用36头初始体重为(7.43±0.12) kg的健康仔猪,按照随机区组设计分为3组,每组12头。日粮处理组分别为不含抗生素的基础日粮组、抗生素组和褐藻糖胶组;试验期为28d。评价褐藻糖胶对仔猪生长性能和营养物质消化率的影响;通过比色法和酶联免疫吸附法检测血清中与免疫相关的指标;通过16S rRNA扩增子高通量测序检测试验第0、14和28天肠道微生物多样性。【结果】日粮添加褐藻糖胶可降低试验0–14 d仔猪耗料增重比(P0.05),但对试验全期仔猪平均日增重和平均日采量无显著影响(P0.05)。与对照组相比,饲喂褐藻糖胶日粮后,仔猪的中性洗涤纤维和酸性洗涤纤维表观消化率显著提高(P0.05);仔猪饲喂抗生素和褐藻糖胶日粮后,血清IL-22含量显著降低。试验第14天,抗生素组和褐藻糖胶处理组中Bacteroidetes数量呈上升趋势(P=0.07);试验第28天,抗生素组和褐藻糖胶处理组Actinobacteria丰度显著高于对照组(P0.05),且褐藻糖胶处理组Bacteroides属的菌群丰度显著高于对照组和抗生素组。【结论】日粮添加褐藻糖胶提高了断奶仔猪纤维养分消化率和拟杆菌属的丰富度和多样性,并且降低了促炎性细胞因子IL-22含量,这有助于缓解仔猪的断奶应激反应,建立稳定健康肠道菌群。     

Effects of the level of feed intake and ergot contaminated concentrate on ruminal fermentation and on physiological parameters in cows

The aim of the present study was to examine the effects of ergot contaminated feed concentrate at differing levels of feed intake on ruminal fermentation, and on various physiological parameters of dairy cows. Twelve double fistulated (in the rumen and the proximal duodenum) Holstein Friesian cows were fed either a control diet (on a dry matter (DM) base: 60% maize silage, 40% concentrate) or a diet containing ergot alkaloids (concentrate contained 2.25% ergot resulting in an ergot alkaloid concentration of the daily ration between 505 and 620 (μg/kg DM) over a period of four weeks. Daily feed amounts were adjusted to the current performance which resulted in a dry matter intake (DMI) variation between 6.0 and 18.5 kg/day. The resulting ergot alkaloid intake varied between 4.1 and 16.3 (μg/kg body weight when the ergot contaminated concentrate was fed. Concentrations of isovalerate, propionate and ammonia nitrogen in the rumen fluid were significantly influenced by ergot feeding, and the amount of ruminally undegraded protein, as well as the fermentation of neutral detergent fibre, tended to increase with the ergot supplementation at higher levels of feed intake, which might indicate a shift in the microbial population. Other parameters of ruminal fermentation such as ruminai pH, fermented organic matter as a percentage of intake, or the amount of non-ammonia nitrogen measured at the duodenum were not significantly influenced by ergot feeding. The activities of liver enzymes (aspartate aminotransferase, γ-glutamyltransferase, glutamate dehydrogenase, creatine kinase) in the serum were not affected by ergot feeding. The rectal measured body temperature of the cows significantly increased after ergot administration (p=0.019). Thus, body temperature can be regarded as a sensitive parameter to indicate ergot exposure of dairy cows.     

Performance,rumen fermentation,blood minerals,leukocyte and antioxidant capacity of young Holstein calves receiving high-surface ZnO instead of common ZnO

ABSTRACT

This study was conducted to assess the effect of feeding high-surface ZnO instead of common ZnO on the performance, rumen fermentation, blood minerals, leukocytes and antioxidant capacity of pre- and post-weaning calves. Thirty male suckling Holstein calves were allotted to one of three experimental groups (10 replicates) in a completely randomised design. Calves received: (1) a low Zn diet without Zn supplementation (control diet), (2) a high Zn diet containing 50 mg supplementary Zn/kg dry matter (DM) as common ZnO or (3) a high Zn diet containing 50 mg supplementary Zn/kg DM as high-surface ZnO (nano-ZnO). The control diet contained a native Zn content of 35.5, 34.7 or 33.7 mg/kg DM for the age periods of 7 to 30, 31 to 70 and 71 to 100 d, respectively. Supplementation of the diet with Zn did not change the dry matter intake (DMI) of calves during d 7 to 30 but increased the ADG in this period (p < 0.05). During age periods of 31 to 70 and 71 to 100 d, DMI and ADG of the Zn supplemented calves were higher (p < 0.05) than the control animals. The nutrient digestibility and the concentration of rumen volatile fatty acids were positively affected (p < 0.05) and the rumen ammonia-N concentration decreased (p < 0.05) by dietary Zn supplementation. Furthermore, the incidence of diarrhoea and pneumonia was lower in calves receiving the Zn supplemented diets. Irrespective of ZnO source, the blood total antioxidant capacity, leukocyte and haematocrit levels significantly increased (p < 0.05) with the ZnO supplemented diets. The post-weaning DMI, nutrient digestibility and blood haematocrit levels were higher in calves receiving high-surface ZnO, compared to those supplemented with common ZnO. With inclusion of the Zn sources in pre- and post-weaning diets, the blood Zn concentration increased (p < 0.05), but the blood Cu, Fe, Ca, P and Mg levels remained unchanged. Regardless of source, dietary supplementation of young calves with ZnO improved the performance and decreased rumen ammonia-N and the incidence of diseases. Moreover, high-surface ZnO had advantages over common ZnO in increasing the post-weaning feed intake, digestibility and blood Zn concentration.     

Zum Einfluss einer hydrothermischen Behandlung auf den Ergotalkaloidgehalt von mutterkornbelastetem Roggen

Hydrothermal treatments are primarily used to increase the digestibility of nutrients and therefore to improve the feeding value of feedstuffs mainly for non-ruminants. Other positive side effects may occur, e.g. a decrease in toxicity of feed contaminated with mycotoxins. To study such effects, 4 batches of rye containing different percentages (0.8, 4.2, 8.3 and 25%) of ergot (Claviceps purpurea) were expanded and ergot alkaloid contents were analysed. After pre-conditioning of each batch by steam exposure for approx. 2 min, at 95 °C and 17% moisture, the material was expanded for approx. 5 sec. at 120 °C, 18% moisture, 40 bar mechanical pressure and 20 kWh/t mechanical energy input. Samples were collected before and after pre-conditioning and after expanding. Ergot alkaloids were analysed by HPLC. Analysis includedErgometrine, Ergotamine, Ergocornine, Ergocryptine, Ergocristine, Ergosine and their respective-inine isomers, the sum of these 12 ergot alkaloids was referred to as the total alkaloid content. On average, the hydrothermal treatment (pre-conditioning and expanding) caused a decrease of the total ergot alkaloid content of approx. 10%. Except for the batch containing 0.8% ergot, the efficiency of the hydrothermal treatment decreased with increasing ergot concentration in the batches. In general, the hydrothermal treatment changed the proportions of the ergot alkaloid isomers since the percentages of the-inine isomers of the total ergot alkaloid contents were increased with reduced-ine percentages. Whether this alteration is of toxicological relevance should be evaluated in animal experiments.     

Toxic effects,metabolism, and carry-over of ergot alkaloids in laying hens,with a special focus on changes of the alkaloid isomeric ratio in feed caused by hydrothermal treatment

Ergot alkaloids (EA) are mycotoxins formed by Claviceps purpurea. Due to the large variation in EA content, the mass proportion of ergot (hardened sclerotia) in animal diets is not suited to establish safe levels of EA. Therefore, the aim of the present study was to examine the dose-dependent effects of dietary EA on laying hens. Ergoty rye or ergot-free rye (control diet) was included in the diets either untreated or after hydrothermal treatment (“expansion”). The total EA levels in five different diets containing 0–3 % of untreated or expanded rye were 0.1–14.56 mg/kg (untreated rye) and 0.08–13.03 mg/kg (expanded rye). The average EA reduction amounted to 11 % due to expanding. The proportions of the sum of all -inine isomers however were consistently higher (19.5–48.4 %) compared to the sum of their -ine isomer counterparts which decreased at the same time. Most of the laying performance and reproductive traits were significantly compromised during the test period between weeks 22 and 42 of age when the diet with the highest EA content was fed. Toxic effects were less pronounced due to expanding. Relative weights of liver, proventriculus, and gizzard as well as the aspartate aminotransferase activity, the antibody titers to Newcastle disease virus, albumin, and total bilirubin concentrations were all significantly increased in hens fed at the highest dietary ergot level whereby expanding additionally modified the albumin and total bilirubin responses. No carry-over of EA into egg yolk and albumen, blood, liver, and breast muscle was found, but bile contained quantifiable levels of ergometrine and ergometrinine. Biological recovery of ingested individual alkaloids with the excreta varied from 2 to 22 % and was strongly positive linearly related to the octanol to water partition coefficient (logk_OW). This suggests the lipophilicity of alkaloids as a factor influencing their metabolism and elimination. Based on the overall results of this study, a lowest observed adverse effect level (LOAEL) of 14.56 mg EA/kg for laying hen diets can be proposed, while the no observed adverse effect level (NOAEL) corresponds to a dietary EA level of 3.72 mg/kg. However, it must be stressed that these critical levels apply for the specific EA pattern tested in the present experiment, while batches of ergot containing a less typical alkaloid composition, or other expanding conditions, might contribute to variations in the LOAEL/NOAEL.     

Contribution of ergot alkaloids to suppression of a grass-feeding caterpillar assessed with gene knockout endophytes in perennial ryegrass

Neotyphodium and Epichloë species (Ascomycota: Clavicipitaceae) are fungal symbionts (endophytes) of grasses. Many of these endophytes produce alkaloids that enhance their hosts’ resistance to insects or are toxic to grazing mammals. The goals of eliminating from forage grasses factors such as ergot alkaloids that are responsible for livestock disorders, while retaining pasture sustainability, and of developing resistant turf grasses, require better understanding of how particular alkaloids affect insect herbivores. We used perennial ryegrass Lolium perenne L. (Poaceae) symbiotic with Neotyphodium lolii × Epichloë typhina isolate Lp1 (a natural interspecific hybrid), as well as with genetically modified strains of Lp1 with altered ergot alkaloid profiles, to test effects of ergot alkaloids on feeding, growth, and survival of the black cutworm, Agrotis ipsilon (Hufnagel) (Lepidoptera: Noctuidae), a generalist grass‐feeding caterpillar. Neonates or late instars were provided clippings from glasshouse‐grown plants in choice and rearing trials. Wild‐type endophytic grass showed strong antixenosis and antibiosis, especially to neonates. Plant‐endophyte symbiota from which complex ergot alkaloids (ergovaline and lysergic acid amides such as ergine) or all ergot alkaloids were eliminated by endophyte gene knockout retained significant resistance against neonates. However, this activity was reduced compared to that of wild‐type Lp1, providing the first direct genetic evidence that ergot alkaloids contribute to insect resistance of endophytic grasses. Similarity of larval response to the two mutants suggested that ergovaline and/or ergine account for the somewhat greater potency of wild‐type Lp1 compared to the knockouts, whereas simpler ergot alkaloids contribute little to that added resistance. All of the endophyte strains also produced peramine, which was probably their primary resistance component. This study suggests that ergot alkaloids can be eliminated from an endophyte of perennial ryegrass while retaining significant insect resistance.     

博落回提取物替代抗生素对肉鸡生长性能、盲肠微生物及盲肠紧密连接的影响

【目的】本研究旨在探讨博落回提取物(Macleayacordataextract,MCE)替代促生长抗生素(Antibiotic growth promoters,AGPs)对黄羽肉鸡生长性能、盲肠微生物及紧密连接mRNA表达的影响。【方法】试验选取体重相近、体型均匀、健康状况良好的1日龄温氏新黄鸡二号公鸡300只,随机分为5组,每组6个重复,每个重复10羽。分别饲喂基础日粮(NC)、抗生素日粮(ANT,基础日粮添加50 mg/kg那西肽和50 mg/kg金霉素)和试验日粮(基础日粮中添加200、400、800 mg/kg MCE),试验期60 d。【结果】日粮添加400 mg/kg MCE替代AGPs显著降低了料肉比(P0.05),并显著增加了盲肠长度(P0.05)。日粮添加MCE显著提高了肉鸡盲肠食糜中Firmicutes细菌数量和ClostridiumclusterXIVa数量(P0.05);MCE替代AGPs显著降低了盲肠Escherichia coli数量(P0.05)。400 mg/kg和800 mg/kg MCE替代日粮中AGPs显著增加了肉鸡盲肠食糜中总短链脂肪酸、乙酸和丁酸含量(P0.05);400 mg/kg MCE替代AGPs显著提高了盲肠中支链脂肪酸异丁酸和异戊酸的浓度(P0.05)。日粮添加MCE显著上调了肉鸡盲肠Claudin-1、JAM2、ZO-1的mRNA表达量(P0.05),并降低了黏蛋白MUC2、MUC5ac和MUC13的表达量(P0.05)。【结论】MCE替代AGPs可通过提高盲肠有益菌数量和短链脂肪酸浓度,促进肠道发育,提升肠道屏障功能等途径,改善黄羽肉鸡生长性能,本研究中其最适添加量为400 mg/kg。     

the effect of the combination of microbial phytase and amino acid supplementation of diets for finishing pigs on p and n excretion and carcass quality

The objective of this study was to evaluate the effect of a combined low-protein, low-phosphorus diet supplemented with limiting amino acids and microbial phytase on performance, nutrient utilization and carcass characteristics of late-finishing barrows. 4?×?8 crossbreed barrows were continuously housed in metabolism cages from 70?–?110?kg BW and were fed diets, either conventional (A) or protein reduced (B) or protein and phosphorus reduced diets (C) based on barley, maize and soybean meal. Diet A (positive control) contained in air dry matter 13% and 10% CP as well as 0.49% and 0.42% P at growth phases I (70?–?100?kg BW) or II (100?–?110?kg BW), respectively. Diet B was low in CP (11.3%, 8.4%), diet C low in CP and low in P (CP: as B, P: 0.36%, 0.30%). To diet B the limiting amino acids lysine, methionine, threonine and trypthophan were added to meet the levels in diet A. To diet C the limiting amino acids and 800 FTU/kg Aspergillus-phytase were supplemented. At the end of the balance periods the barrows were slaughtered, the carcasses scored and loin chops, ham and Phalanx prima IV were analysed for nutrients and minerals. The CP or P reduction in diets B and C did not generally negatively affect growth, feed efficiency, absolute nitrogen retention or overall carcass performances of the pigs. With the low CP diets B and C, N excretion per unit BWG was decreased by about 23%. The addition of microbial phytase (diet C) increased apparent total tract digestibility of P by about 20%. In spite of 30% reduction of P intake (diet C), the absolute P retention related to 1?kg BW did not differ between treatments. Thus, phytase supplementation in diet C reduced P excretion per unit BWG by about 33%. Phytase raised apparent digestibility of Zn by about 20% but not Ca digestibility. Generally the carcass traits and meat characteristics were not affected by any of the diet strategies. Mineralization of the Phalanx prima IV was also similar in all treatment groups. However, phytase supplementation led to significantly increased zinc concentration in bones (25%). In contrast, Fe incorporation into the Phalanx prima IV was not affected. In general, the feeding regimen introduced in this experiment offers substantial benefits in maintaining a sustainable environmental-friendly pork production even at the stage of late-finishing barrows.     

Effects of dietary copper on growth performance, nutrient digestibility and fiber characteristics in cashmere goats during the cashmere slow-growing period

Thirty-six 2.5-year-old wether Inner Mongolian White Cashmere Goats (IMWG) (BW = 42.7 ± 3.44 kg) were used to determine the effects of dietary copper (Cu) concentration on growth performance, nutrient digestibility and fiber characteristics during the cashmere slow-growing period. Wethers were stratified by weight and randomly assigned to four dietary treatments, which included a control diet containing 5.60 mg Cu/kg DM, the control diet supplied, respectively, with 10, 20 and 30 mg Cu/kg DM (total dietary Cu level of 5.60, 15.6, 25.6 and 35.6 mg/kg DM). The experiment lasted 50 days including a 10-day preliminary trial and 10-day metabolism trial. Average daily feed intake (ADFI) did not differ among treatment groups (P > 0.05), except that the supplement providing 30 mg Cu/kg DM decreased average daily gain and gain efficiency (P < 0.05). Copper supplementation had no influence on digestibility of DM, CP and ADF (P > 0.05), however, NDF digestibility of the treatment group supplemented with 30 mg Cu/kg DM was lower compared with that of other groups (P < 0.05). Length and growth rate of cashmere fiber were higher in the treatment group supplemented with 20 mg Cu/kg DM compared with other groups (P < 0.05), but cashmere diameter was not affected by Cu supplementation (P > 0.05). In conclusion, supplementation of Cu at the levels of 10, 20 and 30 mg/kg DM to the basal diet containing 5.60 mg Cu/kg DM had no influence on ADFI or nutrient digestibility of DM, CP and ADF in cashmere goats, while 30 mg Cu/kg DM supplementation had a negative effect on growth performance and NDF digestibility. However, 20 mg Cu/kg DM supplementation of the basal diet enhanced cashmere growth. Hence, the appropriate supplemental level during the cashmere slow-growing period is deemed to be 20 mg Cu/kg DM (total dietary Cu level of 25.6 mg/kg DM).