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Canadian standards allow ≤3000 μg ergot alkaloids/kg cattle feed. A concentration-response relationship was hypothesized between ergot in feed and reductions in plasma prolactin, sperm motility, sperm function, and increase in sperm abnormalities. The study consisted of pre-treatment (12 weeks), treatment (9 weeks), and post-treatment periods (10 weeks). Adult bulls were fed 1113 (n = 8; low ergot group) or 2227 (n = 6; high) μg/kg of dry matter intake. Endpoints were measured every two weeks. Ejaculates were analyzed for sperm concentration, total and progressive motility, plasma membrane and acrosome integrity, mitochondrial membrane potential and sperm abnormalities. Data were analyzed by repeated measures MIXED PROC in SAS. Average outside ambient temperature during the pre-treatment, treatment, and post-treatment periods was −13 (−31 to 1), 0.5 (−18 to 19), and 21 (13–28) °C. Plasma prolactin decreased markedly during treatment (−52.4%; Experimental period p < 0.01). Rectal temperature increased during the treatment and post-treatment periods (EP p < 0.01) but was within the normal physiological range. Bull weight increased during the study (EP p < 0.01). Scrotal circumference in low ergot group increased during treatment (+0.8 cm; Tx∗EP p = 0.05). Progressive motility in high ergot group decreased during treatment (−7%; Tx∗EP p = 0.05), however, semen volume and sperm concentrations were unaffected (p ≥ 0.11). Live sperm with high and medium MMP decreased during treatment (−1.4 and −3.7%; EP p < 0.01). Results suggest that feeding ≤2227 μg ergot alkaloids/kg has only minor effects on adult bull semen quality. • Ergot alkaloid feeding of up to 2227 μg/kg/day for 9 weeks transiently reduced plasma prolactin concentration in adult bulls. • Ergot alkaloid feeding has no effect on sperm concentration, total motility, or ejaculate volume. • Subtle effects on progressive motility and mitochondrial membrane potential were observed in bulls receiving 2227 μg/kg. • Breeding soundness in adult bulls is not expected to be affected at current Canadian standards. • Feeding ≤2227 μg ergot alkaloids/kg has only minor effects on adult bull semen quality. [ABSTRACT FROM AUTHOR]

Vasoconstriction is a known effect associated with ergot alkaloid consumption. The vascular contractile responses are often sustained for an extended period after exposure. Ergot alkaloids exist in two molecular configurations, the C-8-(R)-isomer (R -epimer) and the C-8-(S)-isomer (S -epimer). The sustained vascular contractile response to the R -epimers has been studied previously, unlike the S -epimers which are thought to be biologically inactive. Additionally, antagonists have been utilized to attenuate the vascular contraction associated with the R- epimers of ergot alkaloids utilizing ex vivo techniques. This study utilized an arterial tissue bath to examine and compare the sustained vascular contractile response attributed to ergocristine (R) and ergocristinine (S) using dissected bovine metatarsal arteries. The contractile blocking effect of a noncompetitive alpha-adrenergic antagonist, phenoxybenzamine (POB), was also investigated in precontracted arteries. Arteries (n = 6/epimer) were exposed to a single dose of ergocristine or ergocristinine (1 × 10−6 M in buffer). Each of the epimer doses was followed by a POB (1 × 10−3 M) or methanol (control) treatment at 90 min and the response was observed for another 90 min. Both epimers produced a sustained contractile response over the 180-min incubation period in the control groups. The R -epimer caused a greater sustained contractile response from 60 to 180 min post epimer exposure, compared to the S -epimer (P < 0.05, generalized estimating equations, independent t-test). Phenoxybenzamine caused a decrease in the contractile response induced by ergocristine and ergocristinine from 105 to 180 min, compared to the control (P < 0.05, generalized estimating equations, paired t-test). Overall, these results demonstrate the presence of a sustained vascular contractile response attributed to the R- and S -epimer of an ergot alkaloid with differences in contractile response between the epimers, suggesting differences in receptor binding mechanisms. Furthermore, this study demonstrated that a noncompetitive antagonist could attenuate the sustained arterial contractile effects of both ergot configurations ex vivo. Additional investigation into S -epimers of ergot alkaloids is needed. This research contributes to the understanding of the ergot epimer-vascular receptor binding mechanisms, which may support the investigation of different approaches of minimizing ergot toxicity in livestock. [ABSTRACT FROM AUTHOR]

Investigates the effect of excess dietary iron on liver function, iron and vitamin E status. Characteristics of the CD-1 mice used as laboratory animals; Study design; Diet regimens; Statistical analyses; Comparative efficacy of vitamin E and deferoxamine in acute iron toxicity.

Ethanol is a recognized immunosuppressive agent in the chronic alcoholic. However, the effects of ethanol exposure on the developing immune system have not been extensively investigated. This study evaluated the effects of early postnatal ethanol exposure, via breast milk, on splenic lymphocyte differentiation antigen expression in offspring reared by ethanol-fed mice. Maternal mice were fed a liquid diet containing 20% ethanol-derived calories during pregnancy (E-P), pregnancy and lactation (E-PL), or lactation (E-L). Ad libitumfed (C) and pair-fed (PF) control groups, fed a control liquid diet, were included. Expression of differentiation antigens on splenic lymphocytes from 21-day-old offspring reared by females in 1 of the 3 ethanol exposure conditions was evaluated by flow cytometry. Offspring reared by E-P females had similar numbers of splenic lymphocytes as offspring reared by C and pair-fed during pregnancy (PF-P) females. In contrast, offspring reared by E-PL and E-L females had fewer splenic lymphocytes than both PF-PL and PF-L (respectively), and C offspring. The number of Thy 1.2+, CD4+, CD8+, and IgG+ (B-cell) splenic lymphocytes was reduced in E-PL and E-L offspring compared with PF and C offspring. E-P offspring had fewer CD4+ and IgG+ splenic lymphocytes than C, but not PF-P, offspring. The percentage of Thy 1.2+ splenic lymphocytes was significantly reduced among E-PL and E-L offspring compared with PF-PL and PF-L (respectively), and C offspring. These results suggest that ethanol exposure of female mice during pregnancy, pregnancy and lactation, or lactation alone, alters the phenotypic development of splenic lymphocytes of offspring reared by these females. The greatest effect on differentiation antigen expression occurred when females consumed ethanol during the period of lactation. We speculate that direct exposure of the nursing offspring to ethanol via the breast milk was responsible for the reductions in specific splenic lymphocyte populations. These data demonstrate that mice reared by females fed ethanol during the early postnatal period have a marked depletion of each of the major subpopulations of splenic lymphocytes, and that Thy 1.2+ lymphocytes are differentially sensitive to ethanol. [ABSTRACT FROM AUTHOR]

Ergot alkaloids are produced by the fungus Claviceps purpurea and their levels are carefully monitored in animal and human diets due to their harmful effects and widespread contamination of cereal crops. Ergot alkaloids exist in two forms known as the (R)- and (S)-epimers with only the former being monitored in diets in North America. The (S)-epimers of ergot alkaloids are thought to be biologically inactive and, therefore, harmless. A major mechanism by which the (R)-epimers of ergot alkaloids produce their toxic effect is through vasoconstriction. Therefore, the objective of this study was to examine the vasoactivity potential (contractile response) of four (S)-epimers, namely ergocryptinine, ergocristinine, ergocorninine, and ergotaminine utilizing an in vitro arterial tissue bath system. Bovine metatarsal arteries (n = 6, ergocryptinine and ergocorninine; n = 6, ergocristinine and ergotaminine; n = 6 arteries/(S)-epimer, total n = 12) were collected from healthy mixed-breed beef steers immediately after slaughter, cut into 3-mm arterial cross sections, and suspended in a tissue bath with continuously oxygenated Krebs–Henseleit buffer. To assess the contractile response of each (S)-epimer, a cumulative contractile dose–response curve was constructed by incubating arteries with increasing concentrations (1 × 10−11 to 1 × 10−6 M) of that (S)-epimer. Contractile responses were recorded as grams of tension and were normalized to an initial contraction of phenylephrine. Contrary to the widespread belief, all tested (S)-epimers were found vasoactive and produced a concentration-dependent arterial contractile response similar to what has been reported for the (R)-epimers. The arterial contractile response to ergotaminine was strongest and was significantly greater than that of ergocryptinine and ergocristinine at the highest concentration used (P ≤ 0.01). Our results indicate that the (S)-epimers are biologically active and are likely harmful similar to the (R)-epimers. The levels of (S)-epimers should be carefully monitored in human and animal diets worldwide. [ABSTRACT FROM AUTHOR]

Objectives: The objectives are to compare lead blood concentrations in veterinary workers using lead shielding with concentrations in a control population, to measure hand surface lead before and after use of shielding, and to compare hand surface lead with and without the use of disposable gloves worn under hand shielding. Methods: Blood and hand wipe samples were analyzed for lead using inductively coupled plasma mass spectrometry. Results: There was no difference in blood lead between exposed and control groups. After lead glove use, 69% (18/26) of hand surface lead samples from workers not using disposable gloves were greater than 500 μg, 42% (11/26) were greater than 1000 μg, and 12% (3/26) were greater than 2000 μg. Conclusions: If lead shielding use is unavoidable, disposable gloves should be worn, and skin should be decontaminated after use. [ABSTRACT FROM AUTHOR]

Ergot sclerotia produce toxic secondary metabolites, ergot alkaloids, that infect cereal crops and grasses. Ergot alkaloids have two isomeric configurations: the C-8-R-isomer (R-epimer), and the C-8-S-isomer (S-epimer). Ergot contaminated matrices, such as cereal grains or grasses, may be stored for extended periods at various temperatures before being analyzed, utilized, or consumed. This study assessed the concentration of six common ergot alkaloids in both configurations found in naturally contaminated wheat over time (one, two, and four months) at different temperatures (room temperature, +4 °C, and −20 °C) using ultra-high-performance liquid chromatography–tandem mass spectrometry. The data indicate that the total ergot concentration within a natural contaminated sample varies over time at room temperature, +4 °C, and −20 °C. The total ergot concentration increased until month two, and decreased at month four, independent of temperature (p < 0.05). The total R-epimer concentration appeared to be less stable over time than the total S-epimer concentration. The changes in the total R and total S-epimer concentrations may have been caused by changes in the ergocristine and ergocristinine concentrations, respectively. Time and temperature should be considered when storing potentially contaminated matrices in a laboratory or practical agriculture situations. Quantification of ergot contaminated matrices should occur prior to their use to ensure the most reliable estimates of the concentration of ergot. [ABSTRACT FROM AUTHOR]

The rumen simulation technique (RUSITEC) was used to investigate the effect of ergot alkaloids (EA) and a mycotoxin deactivating product (Biomin AA; MDP) on nutrient digestion, ruminal fermentation parameters, total gas, methane, and microbial nitrogen production. Ruminal fermentation vessels received a feedlot finishing diet of 90:10 concentrate:barley silage (DM basis). Using a randomized complete block design, treatments were assigned (n = 4 vessels/treatment) within two RUSITEC apparatuses in a 2 × 2 factorial arrangement. Treatments included: (1) control (CON) diet (no EA and no MDP); (2) CON diet + 1 g/d MDP; (3) CON diet + 20 mg/kg EA; and (4) CON diet + 20 mg/kg EA + 1 g/d MDP. The study was conducted over 14 d with 7 d of adaptation and 7 d of sample collection. Data were analyzed in SAS using PROC MIXED including fixed effects of EA, MDP, and the EA×MDP interaction. Random effects included RUSITEC apparatus and cow rumen inoculum (n = 4). Ergot alkaloids decreased dry matter (DMD) (P = 0.01; 87.9 vs. 87.2%) and organic matter disappearance (OMD) (P = 0.02; 88.8 vs. 88.4%). Inclusion of MDP increased OMD (P = 0.01; 88.3 vs. 88.9%). Neutral detergent fiber disappearance (NDFD) was improved with MDP; however, an EA×MDP interaction was observed with MDP increasing (P < 0.001) NDFD more with EA diet compared to CON. Acetate proportion decreased (P = 0.01) and isovalerate increased (P = 0.03) with EA. Consequently, acetate:propionate was reduced (P = 0.03) with EA. Inclusion of MDP increased total volatile fatty acid (VFA) production (P < 0.001), and proportions of acetate (P = 0.03) and propionate (P = 0.03), and decreased valerate (P < 0.001), isovalerate (P = 0.04), and caproate (P = 0.002). Treatments did not affect (P ≥ 0.17) ammonia, total gas, or methane production (mg/d or mg/g of organic matter fermented). The inclusion of MDP reduced (P < 0.001) microbial nitrogen (MN) production in the effluent and increased (P = 0.01) feed particle-bound MN. Consequently, total MN decreased (P = 0.001) with MDP. In all treatments, the dominant microbial phyla were Firmicutes, Bacteroidota, and Proteobacteria, and the major microbial genus was Prevotella. Inclusion of MDP further increased the abundance of Bacteroidota (P = 0.04) as it increased both Prevotella (P = 0.04) and Prevotellaceae_UCG-003 (P = 0.001). In conclusion, EA reduced OMD and acetate production due to impaired rumen function, these responses were successfully reversed by the addition of MDP. [ABSTRACT FROM AUTHOR]

As the contamination of cereal grains with ergot has been increasing in Western Canada, studies were undertaken to evaluate the impacts of heating (60, 80, 120, or 190 °C) alone or in combination with pelleting on concentrations of ergot alkaloids. Fifteen samples of ergot-contaminated grain from Alberta and Saskatchewan were assayed for R and S epimers of six alkaloids (ergocryptine, ergocristine, ergocornine, ergometrine, ergosine, and ergotamine) using HPLC MS/MS. Five samples with distinct alkaloid profiles were then selected for heating and pelleting studies. Heating resulted in a linear increase (p < 0.05) of total R and total S epimers with increasing temperature, although some individual R epimers were stable (ergometrine, ergosine, ergotamine). Pelleting also increased (p < 0.05) concentrations of total R and total S epimers detected, although ergometrine concentration decreased (p < 0.05) after pelleting. A feeding study arranged in a 2 × 2 factorial structure used 48 backgrounding Angus-cross steers fed four different diets: (1) Control Mash (CM, no added ergot), (2) Control Pellet (CP), (3) Ergot Mash (EM), or (4) Ergot Pellet (EP). Pelleting heated the ergot to 90–100 °C under 4 bars pressure, but the ergot used in the feeding study was not otherwise heated. Alkaloid concentrations of EM and EP varied by up to 1.1 mg/kg depending on the feed matrix assayed. No differences among treatments were noted for growth performance, feed intake, feed conversion, concentrations of serum prolactin and haptoglobin, hair cortisol, or in temperatures of extremities measured by infrared thermography. The only negative impacts of ergot alkaloids were on blood parameters indicative of reduced immune function or chronic inflammation. Pelleting did not heighten the negative clinical outcomes of ergot, although alkaloid concentrations of pelleted feed increased depending on the matrix assayed. It was hypothesized that the heat and pressure associated with pelleting may enhance the recovery of alkaloids from pelleted feed. [ABSTRACT FROM AUTHOR]

Ergot sclerotia effect cereal crops intended for consumption. Ergot alkaloids within ergot sclerotia are assessed to ensure contamination is below safety standards established for human and animal health. Ergot alkaloids exist in two configurations, the R and S-epimers. It is important to quantify both configurations. The objective of this study was to validate a new ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) method for quantification of six R and six S-epimers of ergot alkaloids in hard red spring wheat utilizing deuterated lysergic acid diethylamide (LSD-D3) as an internal standard. Validation parameters such as linearity, limit of detection (LOD), limit of quantification (LOQ), matrix effects, recovery and precision were investigated. For the 12 epimers analyzed, low LOD and LOQ values were observed, allowing for the sensitive detection of ergot epimers. Matrix effects ranged between 101–113% in a representative wheat matrix. Recovery was 68.3–119.1% with an inter-day precision of <24% relative standard deviation (RSD). The validation parameters conform with previous studies and exhibit differences between the R and S-epimers which has been rarely documented. This new sensitive method allows for the use of a new internal standard and can be incorporated and applied to research or diagnostic laboratories. [ABSTRACT FROM AUTHOR]

Our objectives were to determine if feeding mature and yearling Angus bulls ergot alkaloids (from Claviceps purpurea) within the Canadian permissible limit (∼3 mg/kg) affect post-thaw sperm quality. In Experiment 1, mature Angus bulls were group-fed ergot alkaloids (∼1 and ∼2 mg/kg of daily dry matter intake, DMI; n = 8 and n = 6 bulls, respectively) for 61 d; semen was collected and cryopreserved bi-weekly, from 12 wk pre-exposure to 10 wk post-exposure. In Experiment 2, yearling Angus bulls (12–13 mo) were individually fed placebo or ergot alkaloids (3.4 mg/kg of DMI; n = 7 bulls/group) daily for 9 wk, with semen collected and cryopreserved once weekly, from 5 wk before to 9 wk after exposure. All frozen semen was assessed 0 and 2 h post-thaw. In Experiment 1, post-thaw total and progressive sperm motilities decreased (P ≤ 0.05) from pre-exposure to exposure period, then returned to pre-exposure level. Likewise, during exposure, VAP and VSL decreased (P ≤ 0.01) at 0 h compared to pre-exposure and subsequently returned. Live sperm with intact acrosomes at 2 h post-thaw was affected by ergot (P = 0.01). Medium mitochondrial membrane potential increased (P ≤ 0.01) during exposure compared to pre-exposure and subsequently decreased. In Experiment 2, total and progressive sperm motilities at 0 and 2 h increased (P ≤ 0.01) throughout the study. During post-exposure, VCL, VAP and VSL at 0 h increased (P ≤ 0.01) whereas VSL at 2 h increased (P ≤ 0.01) from pre-exposure to exposure to post-exposure. Live sperm with intact acrosomes increased (P ≤ 0.01) at both 0 and 2 h during post-exposure. Medium mitochondrial membrane potential increased (P ≤ 0.01) from pre-exposure to exposure, followed by a slight decrease post-exposure. Mature Angus bulls partially supported our hypothesis, with only transient effects of ergot on sperm motilities and velocities. Post-thaw sperm characteristics in yearling bulls underwent expected age-related improvements, with any effects of ergot alkaloids potentially masked by sexual maturation. Overall, results partially supported our hypotheses that ergot has no detectable adverse effect on post-thaw sperm characteristics in mature and yearling bulls. • Low-dose ergot had transient effects on post-thaw sperm parameters in mature bulls. • Ergot effect on post-thaw sperm parameters in yearling bulls was masked due to age. • Several post-thaw sperm characters were affected during ergot exposure period. • Current Canadian limits of ergot in feed are safe for post-thaw bull semen quality. [ABSTRACT FROM AUTHOR]

Abstract: The effects of 1min–4h exposures to four Hg compounds (mercuric chloride [HgCl2], methyl mercuric chloride [CH3HgCl], p-chloromercuribenzoate [p-CMB] and thimerosal [TMS; ethylmercurithiosalicylate]) on cell death, microtubules, actin, CD3 receptor expression, protein tyrosine phosphorylation (PTyr-P) and intracellular calcium ([Ca2+]i) levels were investigated in YAC-1 lympoma cells using flow cytometry. YOPRO-1 (YP) and propidium iodide (PI) dye uptake indicated all forms of Hg tested were toxic at concentrations ranging from 25.8–48.4μM, with two distinct patterns of effects. Early apoptosis was prolonged for CH3HgCl- and TMS-treated cells, with more than 50% remaining YP+/PI− after 4h. Both CH3HgCl and TMS induced complete loss of β-tubulin fluorescence, indicative of microtubule depolymerization and inhibition of tubulin synthesis and/or β-tubulin degradation, while F-actin fluorescence diminished to a lesser degree and only after loss β-tubulin. CH3HgCl and TMS induced an almost immediate two-fold increase in CD3 fluorescence, with levels returning to baseline within minutes. With continued exposure, CD3 fluorescence was reduced to approximately 50% of baseline values. Both compounds also increased PTyr-P two- to three-fold immediately, with levels returning to baseline at 4h. Similarly, two- to three-fold increases in [Ca2+]i were noted after 1min exposure. [Ca2+]i increased progressively, reaching levels five- to eight-fold greater than control values. In contrast, dye uptake was delayed with HgCl2 and p-CMB, although cell death proceeded rapidly, with almost all non-viable cells being late apoptotic (YP+/PI+) by 4h. p-CMB produced early reductions in F-actin, and after 4h, complete loss of F-actin with only partial reduction of total β-tubulin was seen with both p-CMB and HgCl2. HgCl2 reduced CD3 expression and PTyr-P slightly within minutes, while p-CMB produced similar effects on CD3 only at 4h, at which time PTyr-P was increased two- to three-fold. Both compounds increased [Ca2+]i within minutes, though levels remained under twice the baseline concentration after 15min exposure. With continued exposure, [Ca2+]i increased to levels two- to five-fold greater than control values. These findings indicate the two groups of Hg compounds may induce cell death by distinct pathways, reflecting interactions with different cellular targets leading to cell death. [Copyright &y& Elsevier]

Our objective was to determine whether feeding yearling bulls with the higher recommended Canadian limit of ergot alkaloids (∼3 mg/kg dry matter intake, DMI) would affect sperm characteristics and plasma prolactin concentrations. Aberdeen Angus bulls (12–13 mo old, n = 7/group) allocated by blocking for sperm concentration and body weight, were fed placebo or ergot alkaloids in gelatin capsules (60 μg/kg body weight daily, 3.4 mg/kg of DMI) for 9 wk. Semen samples were collected weekly by electroejaculation and examined with a computer assisted semen analyzer (CASA) and flow cytometry, for the intervals 5 wk before (Pre-exposure period), 9 wk during (Exposure period) and 9 wk after (Post-exposure period) treatment. Weekly plasma samples were analyzed for prolactin by radioimmunoassay. Plasma prolactin concentrations decreased markedly (mean ± SEM, 16.74 ± 3.70 in Exposure and 33.42 ± 3.08 ng/mL in Post-Exposure periods; P < 0.01) compared to Control (67.54 ± 21.47 and 42.59 ± 15.06 ng/mL). Treatment did not affect (P ≥ 0.17) body weight gain, sperm concentration, sperm count/ejaculate, motility or percent live sperm. Averaged over the exposure and post-exposure durations, the scrotal circumference was smaller (P = 0.02) by 2.7% in the Ergot group. Progressive motility remained unchanged from 59.92 ± 2.31% in Exposure to 59.61 ± 2.59% in Post-Exposure periods, compared to marked increase in Control (61.42 ± 1.60% to 67.52 ± 1.47%; P = 0.02). Straight-line sperm velocity decreased (−3.15 ± 1.53 μm/s) from exposure to post-exposure periods in Ergot group (P = 0.04) versus an increase (2.96 ± 2.17 μm/s) in Control. Midpiece defects decreased from Exposure to Post-exposure periods in Control group but remained unchanged in Ergot group (trt∗age, P < 0.01). Ergot feeding resulted in a smaller proportion of sperm with medium mitochondrial potential (Ergot: 22.65 ± 0.98%, Control: 24.35 ± 1.05%, P = 0.04). In conclusion, feeding ergot at Canadian permissible limit for 9-wk resulted in a 4-fold decrease in plasma prolactin concentrations. Semen end points were not significantly affected, although there were subtle effects on progressive motility, midpiece defects and mitochondrial membrane potential. Clinical relevance of observed changes requires further evaluation. Results supported our hypothesis that prolonged low-level ergot will adversely affect plasma prolactin. However, semen parameters were partially affected, supporting similar work on fescue toxicosis. • Ergot alkaloid feeding at 3.4 mg/kg of DMI/day for 9 weeks of yearling bulls transiently reduced plasma prolactin by 4-folds. • Body weight, scrotal circumference, rectal temperature, or sperm concentrations were not remarkably affected. • Subtle effects on progressive motility, mid-piece defects, and mitochondrial membrane potential were recorded. • Current Canadian ergot standards (3 mg/kg of feed) are adequate for bull reproduction; prolactin decrease is concerning. [ABSTRACT FROM AUTHOR]

This study evaluated the effect of feeding pelleted or mash ergot contaminated grain fed continuously or intermittently on the growth performance, blood serum variables, and carcass quality of finishing beef steers. Sixty black angus steers (442 ± 36.7 kg) were used in a complete randomized finishing (90% concentrate:10% barley silage DM basis) 126-d study. Steers were randomly assigned to 4 different treatments and individually housed. Treatments included: 1) control ration [CON; no added ergot alkaloids (EA)], 2) continuous ergot mash (CEM; fed continuously at 2 ppm total EA), 3) intermittent ergot mash (IEM; fed at 2 ppm EA during the first week of each 21-d period and control diet for the remaining 2 weeks), and 4) intermittent ergot pellet (IEP; fed at 2 ppm EA incorporated into a pelleted supplement during the first week of each 21-d period and control diet for the other 2 weeks). Steers were weighed every 21 d and blood samples were collected on day 0, 42, 84, and 126. Steer DMI (P < 0.01, 9.95 vs. 11.05 kg/day) and ADG (P = 0.04) decreased for all EA treatments compared with the CON. Total shrunk BW gain (P = 0.03, 202.5 vs. 225.2 kg), final BW (P = 0.03, 617.9 vs. 662.2 kg), and carcass weight (P = 0.06) decreased for all EA steers compared with the CON steers. No treatment effects (P > 0.05) were observed for carcass dressing percentage, ribeye area, marbling score, or liver abscess. The percent of carcasses graded AAA decreased for all EA steers compared CON steers (P < 0.01, 46.7 vs. 93.3%). Steers fed EA had increased rectal temperature compared with CON steers (P < 0.01, 39.8 vs. 39.4 °C). Hair cortisol concentrations were less in steers fed IEP (P = 0.05, 1.23 vs. 1.76 pg/mg) than CON. No treatment effects (P > 0.05) were observed for complete blood count, and serum prolactin, haptoglobin, albumin, alkaline phosphatase, alanine transaminase, amylase, calcium, creatine, glucose, lipase, total bilirubin, total protein, or globulin. Blood urea nitrogen was less for EA steers compared with CON (P = 0.01, 3.48 vs. 4.10 mmol/L). The IEM steers had decreased concentrations of serum gamma-glutamyl transferase compared with IEP steers (P = 0.04, 23.4 vs. 28.5 IU). Pelleting ergot contaminated grain did not reduce the impact of ergot alkaloids on any of the measured parameters. Results suggest that continuously or intermittently feeding an ergot contaminated diet (2 ppm EA) can significantly reduce intake, growth performance, and carcass weight, with minimal impact on blood serum variables in finishing steers. Pelleting was not an effective method of reducing ergot toxicity. [ABSTRACT FROM AUTHOR]

Allowable limits for cereal ergot alkaloids in livestock feeds are being re-examined, and the objective of this study was to compare nutrient digestibility, growth performance and carcass characteristics of ram lambs fed a range of alkaloid concentrations, including the maximum currently allowed in Canada (2 to 3 ppm). Four pelleted diets were fed: control, with no added alkaloids; 930; 1402; and 2447 ppb alkaloids based on total R and S epimers. Eight ram lambs (30.0 ± 3.1 kg) were used to examine the impacts of dietary treatments on nutrient digestibility and alkaloid recovery from feces. Concentrations of dietary alkaloids evaluated did not affect nutrient digestibility or N metabolism. Excepting ergocornine and ergocryptine, recovery of alkaloids in feces varied among periods, suggesting that individual lambs may differ in their ability to metabolize ergocristine, ergometrine, ergosine, ergotamine and their S epimers. In a second experiment, ram lambs (n = 47, 30 ± 8 kg) were randomly assigned to a diet and weighed weekly until they achieved a slaughter weight of ≥ 45 kg (average 9 weeks; range 6 to 13 weeks). Intake of DM did not differ (p = 0.91) among diets, although lambs fed 2447 ppb alkaloids had a lower (p < 0.01) ADG than did lambs receiving other treatments. The concentration of serum prolactin linearly declined (p < 0.01) with increasing alkaloids. Feeding 2447 ppb total alkaloids negatively impacted growth, while feeding 1402 ppb did not harm growth performance, but reduced carcass dressing percentage. Due to different concentrations of alkaloids affecting growth and carcass characteristics in the present study, determining allowable limits for total dietary alkaloids will require a better understanding of impacts of alkaloid profiles and interactions among individual alkaloids. [ABSTRACT FROM AUTHOR]

The effects of pelleting feed containing cereal ergot alkaloids was evaluated in performance and nutrient digestibility trials using growing lambs. Defined concentrations of ergot alkaloids [Control (C), no added alkaloids but background concentrations of ∼3 ppb; Low (L), ∼169 ppb; High (H), ∼433 ppb] were achieved by substituting barley grain for ergot-contaminated screenings containing (fed basis) approximately 538 g/kg barley grain, 300 g/kg alfalfa and 160 g/kg canola meal. Diets were fed either as a mash or as a completely pelleted feed. Total alkaloid concentrations did not differ between corresponding mash and pelleted diets, but ergotamine and ergosine were 2–3 times greater in mash feeds, while ergocornine, ergocristine and ergometrine were 2–3 times greater in pelleted diets. The total collection digestibility experiment used 12 ram lambs in a crossover design with 3 experimental periods. Alkaloid dose did not affect digestibility of DM, OM, or CP, but NDF and ADF digestibilities were linearly reduced ( P < 0.05) with increasing alkaloid dose. Alkaloid concentrations in feces depended upon the specific type of alkaloid measured. In preliminary results, ergocristine and ergotamine were the only alkaloids in higher concentrations ( P < 0.001) in feces from lambs fed H as compared to C diets. In the growth experiment, ram and ewe lambs (live weight 24.6 ± 1.08 kg) were randomly assigned to diets, weighed weekly and fed to a slaughter weight of ≥45 kg. Dietary treatments did not affect carcass characteristics, although serum prolactin concentration was linearly reduced ( P < 0.001) by increasing alkaloid dosage and was lower ( P = 0.01) in lambs fed mash as compared to pelleted diets. Although pelleted diets had total alkaloid concentrations that were similar to mash diets, lambs fed pelleted diets had 60 g/d greater ( P < 0.001) ADG than those fed mash diets. For H diets, lambs had lower ADG and feed conversion ( P = 0.03) than those fed C or L, Based on the results of this study, pelleting diets reduced negative impacts of ergot alkaloids possibly by changing alkaloid profiles. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the effect of feeding pelleted or mash ergot contaminated grain continuously or intermittently on performance and blood parameters of backgrounding steers. Sixty black angus steers (300 ± 29.4 kg) were used in a complete randomized backgrounding (60% barley silage:40% concentrate DM basis) 84 d study. Steers were randomly assigned to 4 different treatments and housed individually. Treatments included: 1) control ration (CON; no added ergot), 2) continuous ergot mash (CEM; fed continuously at 2 ppm), 3) intermittent ergot mash (IEM; fed at 2 ppm on the first wk of each 21 d period and control diet for the remaining 2 wk), and 4) intermittent ergot pellet (IEP; fed at 2 ppm during the first wk of each 21 d period and control diet for the other 2 wk). Calves were weighed every 21 days and blood samples were collected on d 0, 42, and 84. No treatment effects (P>0.05) were observed for complete blood count. Steer DMI was reduced for all ergot diets compared to the CON diet (P< 0.01, 7.45 vs. 8.05 kg/d). Steer ADG was reduced for all ergot diets compared to the CON diet (P< 0.01). CEM fed steers had lower ADG (P< 0.01, 0.980 vs. 0.735 kg) and shrunk final weight (P< 0.01, 366 vs. 350 kg) than CON calves, but CEM and IEM were no different. CEM fed steers had lower Gain:Feed (P< 0.07, 0.130 vs. 0.142) than CON calves. Pelleting ergot contaminated grain did not reduce the impact of ergot alkaloids on any of the measured parameters. Results suggest that continuously or intermittently feeding an ergot contaminated TMR (2 ppm) can significantly reduce the growth performance of backgrounded feedlot steers but no effects were observed for blood parameters. Pelleting was not an effective method of reducing ergot toxicity. [ABSTRACT FROM AUTHOR]

This study evaluated the effects of feeding ergot alkaloids (EA) at increasing levels (0, 0.75, 1.5, and 3.0 ppm) to feedlot beef cattle over backgrounding (BG) and finishing (FS) phases on growth performance and carcass quality. Steers (n=240; 280±32 kg) were blocked by weight and randomly allocated to 16 pens (4 pens/treatment; 15 steers/pen). Treatments included: no added EA (CTL); or EA added at 0.75 (EA075); 1.50 (EA150); and 3.0 ppm (EA300). Steers were fed barley-based BG diets containing 40% concentrate: 60% silage (DM basis) for 84 d, then stepped up over 28 d to a 90% concentrate:10% silage (DM basis) FS diet for 119 d. Steers fed EA300 received CTL in FS after 77 days on feed (DOF). In the BG phase, a quadratic decrease (P=0.05) in ADG and a linear decrease in final BW (P=0.03) and total BW gain (P=0.02) were observed with increasing EA. In the FS phase, up to 77 DOF, there was a linear decrease in steers DMI (P=0.04), ADG (P=0.01), and total BW gain (P=0.01) with increasing levels of EA. Over the full FS phase (119 DOF), a quadratic response was observed for ADG (P=0.05), final BW (P=0.05), total BW gain (P=0.02) and carcass weight (P=0.05) with steers fed EA150 showing the lowest performance. Gain:feed was not affected (P>0.20) by EA in the BG or FS phase. Dressing percentage (P=0.02) showed a quadratic effect with EA300 being the lowest. Additionally, a linear increase in lean meat yield (P< 0.001) was observed with increasing EA. Including EA in the diet promoted a linear increase in rectal temperature (P< 0.01). In conclusion, increasing levels of EA in the diet reduced growth performance, but when EA was removed, steers showed compensatory weight gain. [ABSTRACT FROM AUTHOR]

A rumen simulation technique (RUSITEC) investigated effects of ergot alkaloids (E) and a mycotoxin deactivating product (Biomin® AA; B) on nutrient digestion, rumen fermentation, total gas and methane emissions. Fermenters received a finishing diet of 90:10 concentrate:barley silage. Using a randomized complete block design, treatments were assigned (4 vessels/treatment) within two RUSITECs in a 2 × 2 factorial. Treatments included: 1) control diet, 2) control + 1 g B, 3) control + 20 ppm E, and 4) control + 20 ppm E + 1 g B. The study had a 14-d experimental period, with 7-d adaptation and 7-d sample collection. Data were analyzed in SAS using PROC mixed including fixed effects of E, B, and E×B interaction. Random effects included RUSITEC apparatus and cow rumen inoculum (n = 4). Ergot decreased dry matter disappearance (DMD) (P < 0.05; 87.9 vs. 87.2%) and organic matter disappearance (OMD) (P < 0.05; 88.8 vs. 88.4%). Adding B increased OMD (P < 0.05; 88.3 vs. 88.9%) and neutral detergent fiber disappearance (NDFD) (P < 0.01); however, an E×B interaction was observed for NDFD (P < 0.01) with B promoting greater increases with E. Ergot decreased acetate proportions (P < 0.01) and increased isovalerate (P < 0.05). Consequently, acetate:propionate was reduced (P < 0.05) with E. Inclusion of B increased total volatile fatty acids (P < 0.01), and proportions of acetate (P < 0.05) and propionate (P < 0.05), and decreased valerate (P < 0.01), isovalerate (P < 0.01), and caproate (P < 0.01). Treatments did not affect (P = 0.17) ammonia-N, total gas, or methane production (mg/d or mg/g of OM fermented). In conclusion, E reduced OMD and acetate production, but these responses were reversed by the addition of B. [ABSTRACT FROM AUTHOR]

Epidemiology studies have demonstrated increased pulmonary morbidity such as allergy and infection with episodes of high particulate air pollution (size range 0.1-10 mum diameter, PM10), but the mechanism(s) for this association is not yet well defined. The present study was undertaken to evaluate the effects of EHC-93 urban particles (Ottawa dust) on immune functions of peripheral blood mononuclear cells (PBMCs) and splenocytes from male Fischer 344 rats and C57Bl/6 mice. Immune function endpoints evaluated included cell viability, lymphocyte blastogenesis stimulated by T-cell mitogen (concanavalin A, Con A) or B-cell mitogens [lipopolysaccharide (LPS) or LPS/dextran sulfate], intracellular Ca2+ concentration, interleukin 2 (IL-2) production, and expression of receptors for transferrin (TfR) and IL-2 (IL-2R). In addition, the effect of N-acetylcysteine (NAC), an antioxidant, on the toxicity of EHC-93 particles was evaluated. Total EHC-93 particles, water leachate of EHC-93, and washed EHC-93 suppressed proliferation of PBMCs and splenocytes to T- and B-cell mitogens. Treatment of splenocytes with EHC-93 particles did not alter intracellular Ca2 + concentration or m itogen-induced expression of TfR and IL-2R expression, but increased IL-2 production assayed by enzyme-linked immunosorbent assay (ELISA). In spite of an increase in IL-2 production, exogenous IL-2 when added to cultures was able to reverse the suppression of Con A-induced lymphocyte proliferation by EHC-93 particles. Furthermore, the suppressive effect of EHC-93 particles on mitogen-induced lymphocyte proliferation was completely abolished by addition of the antioxidant NAC to cultures, suggesting a possible role of oxidative factors for the toxicity of EHC-93 particles. [ABSTRACT FROM AUTHOR]

Ergotism is a common and increasing problem in Saskatchewan's livestock. Chronic exposure to low concentrations of ergot alkaloids is known to cause severe arterial vasoconstriction and gangrene through the activation of adrenergic and serotonergic receptors on vascular smooth muscles. The acute vascular effects of a single oral dose with high-level exposure to ergot alkaloids remain unknown and are examined in this study. This study had two main objectives; the first was to evaluate the role of α1-adrenergic receptors in mediating the acute vasocontractile response after single-dose exposure in sheep. The second was to examine whether terazosin (TE) could abolish the vascular contractile effects of ergot alkaloids. Twelve adult female sheep were randomly placed into control and exposure groups (n = 6/group). Ergot sclerotia were collected and finely ground. The concentrations of six ergot alkaloids (ergocornine, ergocristine, ergocryptine, ergometrine, ergosine, and ergotamine) were determined using HPLC/MS at Prairie Diagnostic Services Inc., (Saskatoon, SK, Canada). Each ewe within the treatment group received a single oral treatment of ground ergot sclerotia at a dose of 600 µg/kg BW (total ergot) while each ewe in the control group received water. Animals were euthanized 12 h after the treatment, and the pedal artery (dorsal metatarsal III artery) from the left hind limb from each animal was carefully dissected and mounted in an isolated tissue bath. The vascular contractile response to phenylephrine (PE) (α1-adrenergic agonist) was compared between the two groups before and after TE (α1-adrenergic antagonist) treatment. Acute exposure to ergot alkaloids resulted in a 38% increase in vascular sensitivity to PE compared to control (Ctl EC50 = 1.74 × 10−6 M; Exp EC50 = 1.079 × 10−6 M, p = 0.046). TE treatment resulted in a significant dose-dependent increase in EC50 in both exposure and control groups (p < 0.05 for all treatments). Surprisingly, TE effect was significantly more pronounced in the ergot exposed group compared to the control group at two of the three concentrations of TE (TE 30 nM, p = 0.36; TE 100 nM, p < 0.001; TE 300 nM, p < 0.001). Similar to chronic exposure, acute exposure to ergot alkaloids results in increased vascular sensitivity to PE. TE is a more potent dose-dependent antagonist for the PE contractile response in sheep exposed to ergot compared to the control group. This study may indicate that the dry gangrene seen in sheep, and likely other species, might be related to the activation of α1-adrenergic receptor. This effect may be reversed using TE, especially at early stages of the disease before cell death occurs. This study may also indicate that acute-single dose exposure scenario may be useful in the study of vascular effects of ergot alkaloids. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine the potential for accumulation of deoxynivalenol (DON) in yellow mealworm larvae (Tenebrio molitor) reared on high DON Fusarium-infected wheat and investigate the effects on production, survival and nutritional traits. Wheat containing 200 μg/kg DON was used as the control diet. A different source of wheat was sorted into six fractions and mixed to obtain low (2000 μg/kg), medium (10,000 μg/kg) and high (12,000 μg/kg) levels of DON. Each diet was replicated five times with 300 or 200 mealworms per replicate for the feeding and breeding trials, respectively. Trial termination occurred when the first two pupae were observed (32–34 days). There was no difference in the concentrations of DON detected in the larvae between diets that ranged from 122 ± 19.3 to 136 ± 40.5 μg/kg (p = 0.88). Excretion of DON was 131, 324, 230 and 742 μg/kg for control, low, medium and high, respectively. Nutritional analysis of larvae showed maximum crude protein of 52% and crude fat of 36%. Ash, fiber, chitin, fatty-acids and amino-acid content were consistent across diets. Survival was greater than 96% for all life stages and average daily gain ranged from 1.9 ± 0.1 to 2.1 ± 0.1 mg/day per mealworm. Larvae accumulated low levels of DON from Fusarium-infected wheat diets suggesting contaminated wheat could be used to produce a sustainable, safe protein source. [ABSTRACT FROM AUTHOR]

As contamination with cereal ergot has been increasing in western Canada, this study evaluated impacts of feeding a mycotoxin binder (Biomin® II; BB) on nutrient digestibility, alkaloid recovery in feces, and lamb growth performance. Forty-eight ram lambs (25.9 ± 1.4 kg) were randomly assigned to one of four barley-based diets: Control (C), no added alkaloids, Control + BB fed at 30 g/head per day (CBB); Ergot, 2564 ppb total R + S epimers (E); Ergot + BB, 2534 ppb R + S epimers (EBB). Lambs were fed ab libitum for up to 11 weeks until slaughter at >46 kg live weight. Both average daily gain (ADG) and gain/feed ratio were greater (p < 0.01) for lambs fed C and CBB diets as compared with those containing added ergot, although dry matter intake was not affected by dietary ergot or BB. Serum prolactin concentrations were two times higher in EBB- compared with E-fed lambs (p < 0.05), although both were lower than in C or CBB (p < 0.001) lambs. Rectal temperatures were greater in lambs receiving dietary ergot (p ≤ 0.001) than in C- and CBB-fed lambs. In a digestibility study using eight ram lambs, treatment with BB increased neutral detergent fiber (NDF) digestibility (p = 0.01). Nitrogen retention (g) was greater (p < 0.05) for lambs receiving C or CBB compared with ergot-contaminated diets. Feces of EBB lambs had 38.5% greater (p < 0.001) recovery of alkaloids compared with those fed E. Based on sparing of prolactin, BB may reduce impacts of ergot alkaloids by increasing their excretion in feces. Accordingly, concentrations of dietary alkaloids, which would not harm sheep, would be increased by feeding BB. [ABSTRACT FROM AUTHOR]