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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]

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]

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]

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]