Endophyte-Infected Tall Fescue Seed Research Articles

PSII-7 Effect of endophyte-infected tall fescue on body weight, vital signs, and liver function of beef heifers

Abstract Tall fescue was first introduced to the United States over 70 years ago. Since then, it has become the most common forage source for beef cattle in the Southeastern region of the US. Most tall fescue establishes a symbiotic relationship with a toxic fungal endophyte (Epichloë coenophiala), which contributes to the improved vigor of the plant due to acquired resistance to grazing, insects, heat, and drought. However, when consumed by cattle, it may cause fescue toxicosis, a condition characterized by reduced feed intake, body weight (BW) loss, vasoconstriction, and impaired reproductive performance in livestock species. Therefore, the aim of this study was to investigate the effect of endophyte-infected tall fescue consumption on growth performance and health-related traits in beef cattle. For this purpose, 24 Simmental x Angus heifers were divided into two dietary treatments, in which 12 heifers received endophyte-free tall fescue seeds (E-) and 12 heifers were fed with endophyte-infected tall fescue seeds (E+, 6,764 ppb of ergovaline) mixed with the diet for 45 d. The E+ heifers received a daily dose of 20 μg of ergovaline per kg of BW. The E- heifers received the same quantity of seeds as the E+ heifers. For each heifer, phenotypes related to growth (BW), vital signs (respiration rate [RR], and body temperature [TEMP]), and liver functions (serum albumin [ALB], alkaline phosphatase [ALP], aspartate aminotransferase [AST], gamma-glutamyltransferase [GGT], cholesterol [COL], bilirubin [BIL], and triglycerides [TRI]) were analyzed at the end of the experiment. Phenotypes were analyzed using a linear model in R with diet included as a fixed effect. For analysis of BW, the BW at the beginning of the trial was included in the model as a covariate. Results showed that COL and ALP were significantly less (P < 0.05) in the E+ heifers compared with the E- (-32.92 ± 11.16 mg/dL and -32.33 ± 13.95 U/L, respectively). Conversely, E+ heifers had greater (P < 0.05) BW, RR, TEMP, and AST when compared with E- heifers (-17.82 ± 5.12 kg, 25.83 ± 5.52 breaths/min, 0.56 ± 0.12 oC, and 5.83 ± 2.18 U/L, respectively). Measurements of ALB, BIL, GGT, and TRI were not different between E+ and E- heifers. Our results suggest that heifers consuming endophyte-infected tall fescue have compromised vital signs and metabolically altered liver, which may impair growth performance. This study increases our understanding of the biological mechanisms affected by the fescue toxin in beef cattle.

Levodopa attenuates the feed intake reduction caused by ergot alkaloids in cattle.

Consumption of ergot alkaloids from endophyte-infected tall fescue results in losses to the livestock industry in many countries and a means to mitigate these losses is needed. The objective of this study was to evaluate intra-abomasal infusion of the dopamine precursor, levodopa (L-DOPA), on dopamine metabolism, feed intake, and serum metabolites of steers exposed to ergot alkaloids. Twelve Holstein steers (344.9 ± 9.48kg) fitted with ruminal cannula were housed with a cycle of heat challenge during the daytime (32 °C) and thermoneutral at night (25 °C). The steers received a basal diet of alfalfa cubes containing equal amounts of tall fescue seed composed of a mixture of endophyte-free (E-) or endophyte-infected tall fescue seeds (E+) equivalent to 15 µg ergovaline/kg body weight (BW) for 9d followed by intra-abomasal infusion of water (L-DOPA-) or levodopa (L-DOPA+; 2mg/kg BW) for an additional 9d. Afterward, the steers were pair-fed for 5d to conduct a glucose tolerance test. The E+ treatment decreased (P = 0.005) prolactin by approximately 50%. However, prolactin increased (P = 0.050) with L-DOPA+. Steers receiving E+ decreased (P < 0.001) dry matter intake (DMI); however, when supplemented with L-DOPA+ the decrease in DMI was less severe (L-DOPA × E, P = 0.003). Also, L-DOPA+ infusion increased eating duration (L-DOPA × E, P = 0.012) when steers were receiving E+. The number of meals, meal duration, and intake rate were not affected (P > 0.05) by E+ or L-DOPA+. The L-DOPA+ infusion increased (P < 0.05) free L-DOPA, free dopamine, total L-DOPA, and total dopamine. Conversely, free epinephrine and free norepinephrine decreased (P < 0.05) with L-DOPA+. Total epinephrine and total norepinephrine were not affected (P > 0.05) by L-DOPA+. Ergot alkaloids did not affect (P > 0.05) circulating free or total L-DOPA, dopamine, or epinephrine. However, free and total norepinephrine decreased (P = 0.046) with E+. Glucose clearance rates at 15 to 30min after glucose infusion increased with L-DOPA+ (P < 0.001), but not with E+ (P = 0.280). Administration of L-DOPA as an agonist therapy to treat fescue toxicosis provided a moderate increase in DMI and eating time and increased plasma glucose clearance for cattle dosed with E+ seed.

Hepatic transcript profiling in beef cattle: Effects of feeding endophyte-infected tall fescue seeds.

The objective of our study was to evaluate the effect of endophyte-infected tall fescue (E+) seeds intake on liver tissue transcriptome in growing Angus × Simmental steers and heifers through RNA-seq analysis. Normal weaned calves (~8 months old) received either endophyte-free tall fescue (E-; n = 3) or infected tall fescue (E+; n = 6) seeds for a 30-d period. The diet offered was ad libitum bermudagrass (Cynodon dactylon) hay combined with a nutritional supplement of 1.61 kg (DM basis) of E+ or E- tall fescue seeds, and 1.61 kg (DM basis) of energy/protein supplement pellets for a 30-d period. Dietary E+ tall fescue seeds were included in a rate of 20 μg of ergovaline/kg BW/day. Liver tissue was individually obtained through biopsy at d 30. After preparation and processing of the liver samples for RNA sequencing, we detected that several metabolic pathways were activated (i.e., upregulated) by the consumption of E+ tall fescue. Among them, oxidative phosphorylation, ribosome biogenesis, protein processing in endoplasmic reticulum and apoptosis, suggesting an active mechanism to cope against impairment in normal liver function. Interestingly, hepatic protein synthesis might increase due to E+ consumption. In addition, there was upregulation of "thermogenesis" KEGG pathway, showing a possible increase in energy expenditure in liver tissue due to consumption of E+ diet. Therefore, results from our study expand the current knowledge related to liver metabolism of growing beef cattle under tall fescue toxicosis.

Effects of endophyte-infected tall fescue on performance of genotyped pregnant beef cows supplemented with rumen-protected niacin

A total of 28 Angus × Simmental pregnant dams (11 cows and 17 heifers) were selected based on genetic resistance to fescue toxicosis based on a commercial genetic test (T-snip™, Ag. Botanica, Columbia, MO). Subsequently, dams were divided based on genetic resistance to fescue toxicosis and randomly assigned to dietary treatments: 1) Susceptible Control (SC; n = 7); 2) Susceptible Niacin (SN; n = 7); 3) Tolerant Control (TC; n = 7); and 4) Tolerant Niacin (TN; n = 7). All animals received 1.16 kg of endophyte-infected (E+) tall fescue seeds for a period of 30 days. Ergovaline concentration in fescue seeds was ∼5,000 ppb on a DM basis. Dams in SN and TN groups received 6 g/hd/day as-fed of top-dressed rumen-protected niacin, following manufacturer's maximum dose recommendation. Dams in the TN group experienced an accelerated reduction in BW as compared to the rest of the treatments. However, TN offspring did not show BW differences at birth or weaning as compared to those born to dams in other treatments. Milk production was estimated by the weigh-suckle-weigh method, and no difference was observed among treatments. All dams had a reduction in circulating prolactin concentration, indicating that all animals were experiencing fescue toxicosis. In addition, blood metabolites that indicate liver health status were markedly decreased at the end of the study. Overall, these results suggest that dams receiving E+ tall fescue seeds were effectively exposed to fescue toxicosis symptoms. Nevertheless, neither rumen-protected niacin supplementation nor genetic test for resistance to fescue toxicosis could be used as an efficient mechanism of dampening these symptoms.

PSIX-9 The Effect of Endophyte-Infected Tall Fescue Seed Consumption on gut and Satiety Hormones Related to Intake in Holstein Steers

Abstract The objective of this study was to evaluate the impact of endophyte-infected tall fescue (E+) seed, and ergovaline (ERV), on gut and satiety hormones and investigate changes in post-absorptive metabolism. Holstein steers (n=12; 260 ± 16 kg) were assigned to one of three treatments (ERV concentration in diet dry matter): 0, 1.8, and 2.7 ppm with animals being adapted to an indoor environment for 4 days followed by a 7-day diet adaptation and a 10-day treatment period. On days 16 and 17, blood was collected via jugular catheters at 20-min intervals for 8 hours beginning 1 hour pre-feeding. Plasma was extracted and analyzed for insulin, leptin, and active ghrelin. Non-esterified fatty acids (NEFA), b-hydroxybutyrate (BHB), and glucose were analyzed to evaluate changes in postabsorptive metabolism using plasma from each 60-min interval. DMI decreased linearly with increased ERV concentration (P&amp;lt; 0.0001). A quadratic increase was observed for insulin with the 2.7 ppm ERV treatment having the greatest concentrations (P&amp;lt; 0.0001). A quadratic response was observed for leptin where the 1.8 ppm ERV treatment had the greatest concentrations (P&amp;lt; 0.0001). Active ghrelin concentrations decreased linearly with increasing ERV concentrations (P=0.047). A treatment-by-time interaction was observed for NEFA (P&amp;lt; 0.0001) where the 1.8 ppm ERV decreased from pre-feeding to 1-hour post-feeding and did not differ from control thereafter whereas, the 2.7 ppm ERV treatment increased above the 0 ppm ERV treatment beginning 5 hours post-feeding and was greatest among all treatments at 6 hours post-feeding. The 2.7 ppm ERV treatment exhibited the least BHB concentrations (P=0.029). Glucose concentrations increased linearly with increasing ERV concentrations (P=0.046). These results indicate that consumption of E+ seed decreases intake which may be possible through alteration of hormones and may also alter post-absorptive metabolism.

Complete Blood Count Analysis on Beef Cattle Exposed to Fescue Toxicity and Rumen-Protected Niacin Supplementation.

Simple SummaryFescue toxicity results from cattle consuming fungal (Ergot spp.) endophyte-infected tall fescue. Ergot alkaloids like ergovaline produce vasoconstriction in cattle. Our objectives were to analyze changes in complete blood count and performance due to ergot alkaloid detoxification in growing beef cattle and the effect of selecting dams tolerant or susceptible to fescue toxicity based on their tolerance index, measured through a genetic test currently available for beef producers. Furthermore, rumen-protected niacin supplementation is proposed as a potential alleviator for vasoconstriction produced by fescue toxicity. Therefore, we assessed the effects of consuming endophyte-infected tall fescue seeds in addition to rumen-protected niacin supplementation in offspring performance and hematological parameters. Signs for anemia were noticed in susceptible heifer offspring that did not receive rumen-protected niacin, whereas inflammation or infection was detected in tolerant steers that received niacin in their diet. Typical symptoms of heat stress and intoxication with ergot alkaloids were noticed in offspring. Our results suggest that susceptible heifer offspring might have a more active detox metabolism when under fescue toxicity. Findings from this study could be utilized as a new tool to help beef cattle producers to dampen the adverse effects of fescue toxicity.Offspring born to dams genetically tested for resistance to fescue toxicity were separated in groups based on their dams’ resistance level (tolerant vs. susceptible). Rumen-protected niacin (RPN) is proposed as a potential alleviator for vasoconstriction produced by fescue toxicity. Complete blood count (CBC) analysis was utilized for detection of significant responses to treatments applied. Our objectives were as follows: (a) to analyze changes in CBC due to fescue toxicity, maternal resistance level, and RPN in growing offspring; and (b) to assess the effects of maternal resistance level when consuming endophyte-infected tall fescue seeds in addition to RPN in offspring performance. Body weight, average daily gain, or health status were not improved by RPN or the genetic test to detect fescue toxicity resistance. Typical signs of alkaloids intoxication and heat stress were noticed in offspring. Particularly, rectal temperature was greater for susceptible control heifers. Results showed that susceptible control offspring presented signs of anemia denoted by low mean corpuscular hemoglobin (MCH) and mean corpuscular volume (MCV). High levels of white blood cells (WBC) and basophils in combination to low neutrophils to lymphocytes ratio were the signs of infection or inflammation detected in the CBC analysis, especially in tolerant niacin steers. Furthermore, offspring of control heifers had a greater percentage of reticulocytes and RDW, denoting signs of anemia.

Evaluation of Alterations in Uterine Blood Flow using Doppler Ultrasonography in Pregnant, Genotyped Beef Cows and Heifers Consuming Endophyte-Infected Tall Fescue Seeds and Supplemented with Rumen-Protected Niacin

Fescue toxicity is a nutritional-related disease generated in a forage-based beef herd exposed to ergot alkaloids (i.e. ergovaline) present in endophyte-infected tall fescue that produces important economic losses. The combination of a genetic test for susceptibility to fescue toxicity and supplementation with rumen-protected niacin could potentially reduce the toxic effects of ergovaline on beef cow and heifers’ reproductive performance during mid-gestation by improving uterine blood flow. Our main objective was to use color Doppler ultrasonography to evaluate the occurrence of any alteration in uterine arterial blood flow in pregnant, genotyped beef cows and heifers exposed to endophyte-infected tall fescue seeds and supplemented with rumen-protected niacin. We hypothesize that genetically-tested susceptible control beef cows will have narrower uterine arteries and decrease blood flow as compared to tolerant cows that received rumen-protected niacin. Rumen-protected niacin was selected for this study due to its well-known effect as a vasodilator. Therefore, it might help cope with blood vessel constriction generated by ergovaline present in endophyte-infected tall fescue seeds. Results showed the negative effect of exposure to ergovaline in the uterine blood flow of pregnant beef cattle through an increase in the resistivity index. No Doppler parameters detected positive effects of genetic and nutritional treatments.

75 Effects of endophyte-infected tall fescue on performance of genotyped pregnant beef cows and heifers supplemented with rumen-protected niacin

Abstract Fescue toxicity is the result of cattle consuming fungal (Ergot spp.) endophyte tall fescue, a perennial forage widely used in the United States. Ergot alkaloids produce vasoconstriction; however, rumen-protected Niacin (RPN), known by its vasodilation ability, may act as an alleviator for fescue toxicity. Our objective was to assess the effects of a genetic test for fescue toxicity susceptibility, and RPN supplementation on animal performance, hepatic gene expression, and uterine arteries blood flow of Angus × Simmental pregnant animals consuming endophyte-infected tall fescue seeds. Ninety days prior to calving, genotyped pregnant cows (n = 11) and heifers (n = 17) were stratified by body weight (BW; 540 ± 207 kg) and genetic resistance to fescue toxicity (susceptible or tolerant); and randomly assigned to dietary treatments: 1) Susceptible Control (SC); 2) Susceptible Niacin (SN); 3) Tolerant Control (TC); and 4) Tolerant Niacin (TN). Animals’ BW and liver samples were obtained on days 0 and 29. Uterine arteries blood flow was measured using Doppler ultrasonography on treatment days 3, 10, 17, and 23. Messenger RNA was extracted from liver samples for RT-qPCR. Gene expression and BW data were analyzed using the PROC MIXED procedure of SAS, and uterine arteries blood flow was analyzed with the GLIMMIX procedure of SAS. Between day 0 and 29, SOD1 and CYP2E1 were upregulated (P &amp;lt; 0.05) in TC and SC, respectively. Furthermore, SOD2 expression in SC was significantly lower (P &amp;lt; 0.05) on day 29. Genetic test and RPN did not affect uterine arteries’ blood flow. TN animals had a greater decrease in BW compared with other treatments (P &amp;lt; 0.01). In conclusion, Doppler ultrasonography did not detect any changes in uterine arteries blood flow and, supplementation with RPN may influence the oxidative status of cows’ liver consuming endophyte-infected fescue seeds.

Rumen and Serum Metabolomes in Response to Endophyte-Infected Tall Fescue Seed and Isoflavone Supplementation in Beef Steers.

Fescue toxicosis impacts beef cattle production via reductions in weight gain and muscle development. Isoflavone supplementation has displayed potential for mitigating these effects. The objective of the current study was to evaluate isoflavone supplementation with fescue seed consumption on rumen and serum metabolomes. Angus steers (n = 36) were allocated randomly in a 2 × 2 factorial arrangement of treatments including endophyte-infected (E+) or endophyte-free (E−) tall fescue seed, with (P+) or without (P−) isoflavones. Steers were provided a basal diet with fescue seed for 21 days, while isoflavones were orally administered daily. Following the trial, blood and rumen fluid were collected for metabolite analysis. Metabolites were extracted and then analyzed by UPLC-MS. The MAVEN program was implemented to identify metabolites for MetaboAnalyst 4.0 and SAS 9.4 statistical analysis. Seven differentially abundant metabolites were identified in serum by isoflavone treatment, and eleven metabolites in the rumen due to seed type (p < 0.05). Pathways affected by treatments were related to amino acid and nucleic acid metabolism in both rumen fluid and serum (p < 0.05). Therefore, metabolism was altered by fescue seed in the rumen; however, isoflavones altered metabolism systemically to potentially mitigate detrimental effects of seed and improve animal performance.

Effects of feeding endophyte-infected tall fescue seeds to stocker Angus steers on retail quality attributes of beef strip steaks

The objective of this study was to determine the effects of feeding endophyte-infected tall fescue seeds to Angus steers during the stocker phase on the quality attributes of beef strip steaks during retail display. Endophyte-infected tall fescue seeds had no effect on steak surface lean color, myoglobin forms, proximate composition, thiobarbituric acid reactive substances, aerobic plate count, pH, activity of superoxide dismutase and metmyoglobin reductase, shear force, and sensory attributes (P ≥ 0.087). However, lightness, redness, oxymyoglobin percentage, and MRA decreased from 45.01, 32.60, 67.61%, and 9.54 μM/min/g, respectively, on d 0 to 40.11, 21.83, 48.95%, and 2.30 μM/min/g, respectively, on d 7 (P ≤ 0.001). Thiobarbituric acid reactive substances were increased by 30% by d 5 (P = 0.015) and APC was increased by 0.5 log CFU/g by d 7 (P ≤ 0.012).

142 Impact of Protein Supplementation on Physiological Response of Steers Consuming Endophyte-Infected Tall Fescue Seed.

142 Impact of Protein Supplementation on Physiological Response of Steers Consuming Endophyte-Infected Tall Fescue Seed.

41 “Effect of Protein Supplementation on Immune Response of Weaned Steers Consuming Endophyte-Infected Tall Fescue Seed”.

41 “Effect of Protein Supplementation on Immune Response of Weaned Steers Consuming Endophyte-Infected Tall Fescue Seed”.

Color, Metmyoglobin Reductase Activity, and Lipid Oxidation in Ground Beef Patties during Retail Display from Angus Steers Fed Endophyte-Infected Tall Fescue Seeds

Color, Metmyoglobin Reductase Activity, and Lipid Oxidation in Ground Beef Patties during Retail Display from Angus Steers Fed Endophyte-Infected Tall Fescue Seeds

131 Retail color and aerobic bacterial count of strip steaks from beef cattle fed endophyte-infected tall fescue seeds

131 Retail color and aerobic bacterial count of strip steaks from beef cattle fed endophyte-infected tall fescue seeds

0265 Effects of summer and winter feeding of endophyte infected tall fescue seeds on average daily gain and activity of hepatic cytochrome P450 1A, 2C, 3A, aldo-keto reductase 1C, and uridine 5'-diphospho-glucuronosyltransferase in beef steers

0265 Effects of summer and winter feeding of endophyte infected tall fescue seeds on average daily gain and activity of hepatic cytochrome P450 1A, 2C, 3A, aldo-keto reductase 1C, and uridine 5'-diphospho-glucuronosyltransferase in beef steers

Comparison of two Ammoniation Procedures to Reduce the Toxicity of Endophyte-Infected Tall Fescue Seed Fed to Rats

ABSTRACTTo determine the effect of extending the duration of ammonia (2% dry matter basis) treatment ti'om 1 to 5 wk on the toxicity of endophyte-infected tall fescue seed, 60 male Harlan Sprague-Dawley rats were randomly assigned to the following six treatments during a 28-d trial: endophyte-free (E-), endophyte-infected (E+), 1 wk ammoniated endophyte-fee (1AE-), I wk ammoniated endophyte-infected (1AE+), 5 wk ammoniated endophyte-free (5AE-), and 5 wk ammoniated endophyte-infected (5AE+) tall fescue seed The concentration of total pyrrolizidine alkaloids (N-acetyl and N-formyl loline) orE+ rescue was reduced from 4203 12g/g to 3009 and 2533 I-tg/g by the 1AE+ and 5AE+ treatments, respectively. Ergovaline was lowered from 3.77 to 1.57 12g/g by 1AE+ and eliminated by 5AE+. Endophyte-infected treatment groups had depressed (P<0.0001) dally feed intakes (DFI), daily weight gains (DWG), feed efficiencies (G/F), primary antibody responses, and T cell and B cell mitogenic responses than endophyte-free treatment groups. Ammoniation of endophyte-infected rescue seed improved DFI and DWG (P<0.0001) and G/F (P<0.05); however, there was no difference in performance criteria between the 1-wk and 5-wk ammoniation treatments. Endophyte-induced depressions in immune function were not alleviated by ammoniation.

Ammoniation to Reduce the Toxicity of Endophyte-Infected Tall Fescue Seed Fed to Rats

ABSTRACTTo assess the efficacy of ammoniation in the detoxification of endophyte-infected tall fescue (Festuca arundinacea Schreb.), 40 male Harlan Sprague-Dawley rats were randomly assigned to the following four treatments for 28 d: endophyte-free (E-), endophyte-infected (E+), ammoniated (2% dry matter basis, 7 d) endophyte-free (AE-), and ammoniated endophyte-infected (AE+) tall fescue seed. Total pyrrolizidine alkaloid (N-acetyl and N-formyl loline) and ergovaline contents of endophyte-infected fescue seed were reduced 24 and 54%, respectively, by ammoniation. Endophyte-infected treatment groups had lower (P < 0.01) daily feed intakes (DFI), daily weight gains (DWG), feed efficiencies, and primary serum hemagglutination titers to sheep red blood cell (SRBC) immunization than endophyte-free treatment groups. Performance parameters were higher (P < 0.01) for ammoniated diets in comparison to non-ammoniated dies; however, anti-SRBC titers were not significantly different. When compared to the E+ diet, the AIE+ diet increased (P < 0.01) DFI (24%), DWG (41%) and feed efficiency (13%).

Comparison of two Ammoniation Procedures to Reduce the Toxicity of Endophyte-Infected Tall Fescue Seed Fed to Rats

ABSTRACTTo determine the effect of extending the duration of ammonia (2% dry matter basis) treatment from 1 to 5 wk on the toxicity of endophyte-infected tall fescue seed, 60 male Harlan Sprague-Dawley rats were randomly assigned to the following six treatments during a 28-d trial: endophyte-free (E-), endophyte-infected (E+), 1 wk ammoniated endophyte-free (1AE-), 1 wk ammoniated endophyte-infected (1AE+), 5 wk ammoniated endophyte-free (5AE-), and 5 wk ammoniated endophyte-infected (5AE+) tall fescue seed. the concentration of total pyrrolizidine alkaloids (N-acetyl and N-formyl loline) of E+ fescue was reduced from 4203 äg/g to 3009 and 2533 ä;g/g by the 1AE+ and 5AE+ treatments, respectively. Ergovaline was lowered from 3.77 to 1.57 ä;g/g by 1AE+ and eliminated by 5AE+. Endophyte-infected treatment groups had depressed (P < 0.0001) daily feed intakes (DFI), daily weight gains (DWG), feed efficiencies (G/F), primary antibody responses, and T cell and B cell mitogenic responses than endophyte-free treatment groups. Ammoniation of endophyte-infected fescue seed improved DFI and DWG (P< 0.0001) and G/F (P< 0.05); however, there was no difference in performance criteria between the 1-wk and 5-wk ammoniation treatments. Endophyte-induced depressions in immune function were not alleviated by ammoniation.

Ammoniation to Reduce the Toxicity of Endophyte-Infected Tall Fescue Seed fed to Rats

ABSTRACTTo assess the efficacy of ammoniation in the detoxification of endophyte-infected tall fescue (Festuca arundinacea Schreb.), 40 male Harlan Sprague-Dawley rats were randomly assigned to the following four treatments for 28 d: endophyte-free (E-), endophyte-infected (E+), ammoniated (2% dry matter basis, 7 d) endophyte-free (AE-), and ammoniated endophyte-infected (AE+) tall fescue seed. Total pyrrolizidine alkaloid (N-acetyl and N-formyl loline) and ergovaline contents of endophyte-infected fescue seed were reduced 24 and 54%, respectively, by ammoniation. Endophyte-infected treatment groups had lower (P < 0.01) daily feed intakes (DFI), daily weight gains (DWG), feed efficiencies, and primary serum hemagglutination titers to sheep red blood cell (SRBC) immunization than endophyte-free treatment groups. Performance parameters were higher (P < 0.01) for ammoniated diets in comparison to non-ammoniated diets; however, anti-SRBC titers were not significantly different. When compared to the E+ diet, the AE+ diet increased (P < 0.01) DFI (24%), DWG (41%) and feed efficiency (13%).

Analysis of Ergot Alkaloids in Endophyte-Infected Tall Fescue by Liquid Chromatography/Electrospray Ionization Mass Spectrometry

Previous investigators have identified a number of ergot alkaloids (EAs) in tall fescue (Festuca arundinacea Schreb.) infected by the endophytic fungus, Neotyphoidium coenophialum [(Morgan-Jones & W. Gams) Glenn, Bacon & Hanlin comb. nov.]. Their results, however, may have been confounded by the presence of the related parasitic ergot fungus (Claviceps purpurea [Fr.:Fr.] Tul.), which also produces EAs. Semipreparative HPLC was used to separate fractions giving a high fluorescence response in a sample of endophyte-infected (EI) tall fescue seeds, carefully examined to eliminate the possibility of Claviceps infection. Analytical high-performance liquid chromatography (HPLC) and LC/electrospray ionization mass spectrometry (ESI-MS) were used to identify EAs after isolation. Clearly identified in the spectra were ergine, ergovaline, ergosine, ergonine, and previously undescribed EAs, didehydroergovaline and aci-ergovaline, including their epimers. Several additional EAs may have been present, but structures could not be confirmed by their spectra. Not found in the isolated fractions were ergonovine, ergotamine, or lysergylmethylcarbinolamide. The developed HPLC method was used to determine the alkaloids in plants, culms, and seeds of EI tall fescue. Keywords: Neotyphodium coenophialum; Acremonium coenophialum; Festuca arundinacea, ergovaline