Dominant Remodeling of Cattle Rumen Microbiome by Schedonorus arundinaceus (Tall Fescue) KY-31 Carrying a Fungal Endophyte

AbstractTall fescue KY-31 feeds ~20% of the beef cattle in the United States. It carries a fungal endophyte that produces ergovaline, which causes toxicosis in cattle, leading to $2 billion revenue loss annually. The MaxQ cultivar of the grass is non-toxic, but less attractive economically. To develop ways of mitigating the toxicity, the rumen microbiome of cattle consuming KY-31 and MaxQ have been analyzed, principally for identifying ergovaline transforming microorganisms and often using fecal microbiome as a surrogate. We have hypothesized that KY-31 not only causes toxicosis, but also impacts rumen metabolism broadly, and tested the hypothesis by analyzing rumen microbiome compositions of cattle that grazed MaxQ with an intervening KY-31 grazing period with 16S rRNA-V4 element as identifier. We found that KY-31 remodeled the cellulolytic and saccharolytic communities substantially. This effect was not evident at whole microbiome levels but in the compositions of sessile and planktonic fractions. A move from MaxQ to KY-31 lowered the Firmicutes abundance in the sessile fraction and increased it in planktonic part and caused an opposite effect for Bacteroidetes, although the total abundances of these dominant rumen organisms remained unchanged. In the sessile fraction, the abundances of Fibrobacter, which degrades less degradable fibers, and certain cellulolytic Firmicutes such as Pseudobutyrivibrio and Butyrivibrio 2, dropped, and these losses were apparently compensated by increased occurrences of Eubacterium and specific Ruminococcaceae and Lachnospiraceae. In planktonic fraction the Tenericutes’ abundance increased as saccharolytic Bacteroidetes’ level dropped. Several potential ergovaline degraders were enriched. A return to MaxQ restored the original Firmicutes and Bacteroidetes distributions. However, the Fibrobacter and Butyrivibrio 2 abundances remained low and their substitutes maintained significant presence. The rumen microbiome was influenced minimally by animals’ fescue toxicosis and was distinct from previously reported fecal microbiomes in composition. In summary, KY-31 and MaxQ cultivars of tall fescue were digested in the cattle rumen with distinct consortia and the KY-31-specific features were dominant. The study highlighted the importance of analyzing sessile and planktonic fractions separately.

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Effects of Aminocyclopyrachlor Plus Metsulfuron on Tall Fescue Yield, Forage Quality, and Ergot Alkaloid Concentration

Weed Technology ◽

10.1614/wt-d-15-00122.1 ◽

2016 ◽

Vol 30 (1) ◽

pp. 171-180 ◽

Cited By ~ 3

Author(s):

Trevor D. Israel ◽

Gary E. Bates ◽

Thomas C. Mueller ◽

John C. Waller ◽

G. Neil Rhodes

Keyword(s):

Tall Fescue ◽

Ergot Alkaloid ◽

Crude Protein ◽

Ergot Alkaloids ◽

Forage Quality ◽

The United States ◽

Fungal Endophyte ◽

Fescue Toxicosis ◽

Protein Levels ◽

Spring Harvest

Most tall fescue in the United States is infected with a fungal endophyte which imparts certain advantages to the plant, such as drought tolerance, insect feeding deterrence, and enhanced mineral uptake. However, the endophyte also produces ergot alkaloids that are harmful to livestock and contribute to fescue toxicosis. Because the alkaloids are concentrated in seed and stems, a potential way to reduce the likelihood of fescue toxicosis is by suppressing seedhead formation with herbicides. Research was conducted from 2012 to 2014 using metsulfuron applied alone and in combination with other herbicides in spring to determine the growth response of tall fescue, effects on forage quality, and ergot alkaloid concentration. Clipping or metsulfuron applied alone or in combination with aminocyclopyrachlor or aminopyralid reduced seedhead density by 36 to 55% compared to the nontreated control. Treatments containing metsulfuron reduced spring harvest yield 35 to 61%, but no differences were observed in the summer or year-after harvests. The same treatments increased crude protein levels by 1.03 to 2.14% and reduced acid detergent fiber levels by 1.60 to 2.76% compared to the nontreated control at spring harvest. Treatments containing metsulfuron reduced ergot alkaloid concentration 26 to 34% at the spring harvest, but no differences were observed in summer-harvested forage. Results from this study indicate metsulfuron applied alone or in combination with aminocyclopyrachlor or aminopyralid can potentially reduce the severity of fescue toxicosis and improve forage quality.

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Development of a genetic evaluation for hair shedding in American Angus cattle to improve thermotolerance

Genetics Selection Evolution ◽

10.1186/s12711-020-00584-0 ◽

2020 ◽

Vol 52 (1) ◽

Author(s):

Harly J. Durbin ◽

Duc Lu ◽

Helen Yampara-Iquise ◽

Stephen P. Miller ◽

Jared E. Decker

Keyword(s):

Heat Stress ◽

Beef Cattle ◽

Tall Fescue ◽

The United States ◽

Genetic Evaluation ◽

Functional Enrichment ◽

Fescue Toxicosis ◽

Weaning Weight ◽

Angus Cattle ◽

Genetic Evaluations

Abstract Background Heat stress and fescue toxicosis caused by ingesting tall fescue infected with the endophytic fungus Epichloë coenophiala represent two of the most prevalent stressors to beef cattle in the United States and cost the beef industry millions of dollars each year. The rate at which a beef cow sheds her winter coat early in the summer is an indicator of adaptation to heat and an economically relevant trait in temperate or subtropical parts of the world. Furthermore, research suggests that early-summer hair shedding may reflect tolerance to fescue toxicosis, since vasoconstriction induced by fescue toxicosis limits the ability of an animal to shed its winter coat. Both heat stress and fescue toxicosis reduce profitability partly via indirect maternal effects on calf weaning weight. Here, we developed parameters for routine genetic evaluation of hair shedding score in American Angus cattle, and identified genomic loci associated with variation in hair shedding score via genome-wide association analysis (GWAA). Results Hair shedding score was moderately heritable (h2 = 0.34 to 0.40), with different repeatability estimates between cattle grazing versus not grazing endophyte-infected tall fescue. Our results suggest modestly negative genetic and phenotypic correlations between a dam’s hair shedding score (lower score is earlier shedding) and the weaning weight of her calf, which is one metric of performance. Together, these results indicate that economic gains can be made by using hair shedding score breeding values to select for heat-tolerant cattle. GWAA identified 176 variants significant at FDR < 0.05. Functional enrichment analyses using genes that were located within 50 kb of these variants identified pathways involved in keratin formation, prolactin signalling, host-virus interaction, and other biological processes. Conclusions This work contributes to a continuing trend in the development of genetic evaluations for environmental adaptation. Our results will aid beef cattle producers in selecting more sustainable and climate-adapted cattle, as well as enable the development of similar routine genetic evaluations in other breeds.

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Evaluation of a commercial genetic test for fescue toxicosis in pregnant Angus beef cattle1

Translational Animal Science ◽

10.1093/tas/txaa181 ◽

2020 ◽

Vol 4 (4) ◽

Cited By ~ 1

Author(s):

Justine M Galliou ◽

Piush Khanal ◽

Kyle Mayberry ◽

Matt H Poore ◽

Daniel H Poole ◽

...

Keyword(s):

United States ◽

Body Weight ◽

Body Condition ◽

Tall Fescue ◽

Fixed Effects ◽

Genetic Test ◽

The United States ◽

Economic Losses ◽

Fescue Toxicosis ◽

Phenotypic Trait

Abstract Most tall fescue [Lolium arundinaceum (Schreb.) Darbysh] in the Southeastern United States contains an endophyte that causes fescue toxicosis (FT) in grazing animals, a serious disease that causes approximately $1 billion in economic losses to the animal industries in the United States. Recently, a genetic test called T-Snip (AgBotanica, LCC, Columbia, MO), was developed with the objective of identifying animals with genetic variation for FT tolerance. The aim of this study was to validate the use of this genetic test in mature, pregnant cows. Over 13 wk, weekly phenotypic data, including body weight, rectal temperatures, hair coat scores, hair shedding scores, and body condition scores, were collected on 148 pregnant purebred Angus cows at 2 locations in NC where infected fescue was the primary source of feed. Birth weights (cBW) and 205-d adjusted weaning weights (adjWW) from these cow’s calves were recorded. All cows were genotyped for T-Snip. At the end of the trial, each phenotypic trait was calculated as the slope of the linear regression of performance on weeks. The effect of T-Snip rating genotypes (4 levels) on slope traits was tested using a linear model also including the fixed-effects of location, parity, and the initial measurement for each trait (covariate). For cBW and adjWW, the model also included the sex of the calf and the month of birth as categorical effects. Associations of T-Snip genotypes were observed for body weight gain (aBWd) of pregnant cows (P = 0.15; interaction with location), change in body condition score (aBCSd; P = 0.13), and adjWW (P = 0.06; interaction with location). For aBWd and adjWW, associations were found just within one location (P = 0.017 and 0.047, respectively), which was the location with higher endophyte infection rate. For all associations, the direction of the T-Snip genotypes was the same and as expected: the greater the genotype score, the better performance. No associations were found for the other traits (P > 0.10). These results indicate that the T-Snip test may be predictive of cow performance (aBWd, aBCSd, and adjWW) in an endophyte-infected tall fescue environment.

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Development of a genetic evaluation for hair shedding in American Angus cattle to improve thermotolerance

10.1101/2020.05.21.109553 ◽

2020 ◽

Author(s):

Harly J. Durbin ◽

Duc Lu ◽

Helen Yampara-Iquise ◽

Stephen P. Miller ◽

Jared E. Decker

Keyword(s):

Beef Cattle ◽

Tall Fescue ◽

The United States ◽

Early Summer ◽

Genetic Evaluation ◽

Functional Enrichment ◽

Fescue Toxicosis ◽

Beef Industry ◽

Angus Cattle ◽

Genetic Evaluations

AbstractBackgroundHeat stress and fescue toxicosis caused by ingesting tall fescue infected with the endophytic fungus Epichloë coenophiala represent two of the most prevalent stressors to beef cattle in the United States, costing the beef industry millions of dollars each year. The rate at which a beef cow sheds her winter coat early in the summer is an indicator of adaptation to heat and an economically relevant trait in many parts of the U.S. Further, research suggests that early-summer hair shedding may be reflective of tolerance to fescue toxicosis, as vasoconstriction induced by fescue toxicosis limits the ability of an animal to shed its winter coat. Here, we developed parameters for routine genetic evaluation of hair shedding score in American Angus cattle and identified genomic loci associated with variation in hair shedding score via genome-wide association analysis (GWAA).ResultsHair shedding score was found to be moderately heritable (h2 = 0.34 to 0.40), with differing repeatability estimates between cattle grazing versus not grazing endophyte-infected tall fescue. Our results suggest modestly negative genetic and phenotypic correlations between a dam’s hair shedding score (lower score is earlier shedding) and the weaning weight of her calf, one metric of performance. Together, these results indicate that economic gains can be made via the use of hair shedding score breeding values to select for heat tolerant cattle. GWAA identified 176 variants significant at FDR < 0.05. Functional enrichment analyses using genes within 50 Kb of these variants identified pathways involved in keratin formation, prolactin signaling, host-virus interaction, and other biological processes.ConclusionsThis work contributes to a continuing trend in the development of genetic evaluations for environmental adaptation. The results of this work will aid beef cattle producers in selecting more sustainable and climate-adapted cattle, as well as enable the development of similar routine genetic evaluations in other breeds.

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Discovery of novel microorganisms involved in ergot alkaloid detoxification: An approach

NZGA: Research and Practice Series ◽

10.33584/rps.13.2006.3142 ◽

2007 ◽

Vol 13 ◽

pp. 395-398

Author(s):

S. Perumbakkam ◽

R.M. Rattray ◽

M.J.M. Delorme ◽

J.M. Duringer ◽

A.M. Craig

Keyword(s):

Tall Fescue ◽

Festuca Arundinacea ◽

Ergot Alkaloids ◽

The United States ◽

Fescue Toxicosis ◽

United States Department ◽

Department Of Agriculture ◽

Toxic Alkaloids ◽

Future Work ◽

Endophyte Fungi

Fescue toxicosis and ergot alkaloids are estimated by the United States Department of Agriculture (USDA) to cost the U.S. ranchers $860 million per year. The endophyte fungi Neotyphodium coenophialum is present in tall fescue (Festuca arundinacea). This fungus produces toxic alkaloids (principally ergovaline) that cause deleterious effects in cattle and other livestock when infected grasses are eaten. Previous studies in sheep and cattle have yielded no culturable microbes able to detoxify the ergot molecules, leading to the search for novel sources of anaerobic organisms capable of degrading ergot alkaloids. Anaerobic incubation of earthworm (Eisenea fetida) homogenate with pure ergovaline has exhibited a 60% decrease in ergovaline concentration. Digestive tracks were dissected from worms obtained from an endophyte-fed digester. Cloning and partial sequencing of bacterial 16S rDNA obtained from these samples revealed a diverse microbiota, including bacteria sequences which classified into the phyla Bacteroidetes, Firmicutes, Proteobacteria, and Planktomycetes. Future work is focused on refining our understanding of the contribution towards possible ergot alkaloids detoxification made by the bacteria of the worm-gut microbiota. Keywords: ergovaline, microbial degradation, endophyte, tall fescue, perennial ryegrass, Eisenea fetida

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Assessing Remote Sensing Vegetation Index Sensitivities for Tall Fescue (Schedonorus arundinaceus) Plant Health with Varying Endophyte and Fertilizer Types: A Case for Improving Poultry Manuresheds

Remote Sensing ◽

10.3390/rs13030521 ◽

2021 ◽

Vol 13 (3) ◽

pp. 521

Author(s):

K. Colton Flynn ◽

Trey Lee ◽

Dinku Endale ◽

Alan Franzluebbers ◽

Shengfang Ma ◽

...

Keyword(s):

Remote Sensing ◽

Satellite Imagery ◽

Tall Fescue ◽

Land Surface ◽

Vegetation Index ◽

Fungal Endophyte ◽

Plant Health ◽

Broiler Litter ◽

Significant Difference ◽

Schedonorus Arundinaceus

Tall fescue (Schedonorus arundinaceus) is a common perennial forage in cattle pastures of the southeastern United States. A mutualistic fungal endophyte normally infects the grass and produces ergot alkaloids toxic to livestock, but fungal biotypes that have no ergot alkaloid production have been developed. Here remote sensing methods were used to assess plant health in 1 ha grazed paddocks with application amongst different combinations of fertilizer sources (inorganic and broiler litter) and endophyte associations (wild, novel–tall fescue MaxQ type with novel endophyte, and free). Broiler litter fertilization is common in the region due to the presence of many chicken farms. Moreover, broiler litter costs are comparable to inorganic fertilizer depending on distance from source to application. Incorporating remote sensing, we tested the sensitivity of three indices: normalized difference vegetation index (NDVI), enhanced vegetation index (EVI), and land surface water index (LSWI) to assess fescue plant health. Indices were obtained from satellite imagery provided by Landsat 7 ETM+ between the years 2005 and 2009. Sensitivity analytics suggested that LSWI was the optimum index to determine fescue plant health. The year experiencing drought (determined by annual precipitation) showed significant difference between fertilizer types (p = 0.05) and a nearly significant difference between endophyte associations (p = 0.08). There was no significant difference in years with normal or wet precipitation rates due to tall fescue endophyte association or type of fertilization. Limited availability of satellite imagery during parts of the five years of study might have influenced outcomes of statistical analyses. Nevertheless, the data and findings point to the potential use of satellite imagery in assessing grazingland tall fescue health and advancing the concept of poultry manureshed in the region or elsewhere where poultry manure production is extensive.

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Influence of Tall Fescue Epichloë endophytes on Rhizosphere Soil Microbiome

10.21203/rs.3.rs-614409/v1 ◽

2021 ◽

Author(s):

Kishan Mahmud ◽

Kendall Lee ◽

Nicholas Hill ◽

Ali Missaoui

Keyword(s):

Tall Fescue ◽

Fungal Community ◽

Soil Microbial Communities ◽

The United States ◽

Fungal Endophyte ◽

Plant Performance ◽

Soil Microbiome ◽

Grass Species ◽

Rrna Gene ◽

Soil Microbial

Abstract Background Tall fescue (Lolium arundinaceum (Schreb.) S.J. Darbyshire) is a popular perennial grass species for livestock production and amenities in the United States. Tall fescue often forms a symbiotic relationship with fungal endophytes (Epichloë coenophiala) which provides increased plant tolerance to environmental stress compared to endophyte-free plants. However, whether this improved plant performance is the sole result of the unique relationship between the grass and the shoot-dwelling fungal endophyte of rhizosphere origin remains a question. This symbiosis possibly regulates the recruitment of beneficial soil microbial communities in endophyte-infected tall fescue rhizosphere and may offer enhanced nutrients and water acquisition, thereby, providing the plant with an increased tolerance level against environmental stresses. We compared the soil bacterial and fungal community composition and investigated possible community shifts in soil microbial populations based on endophyte infection in tall fescue by analyzing the 16s rRNA gene and ITS specific region. Results Our data revealed that bacterial community richness and the evenness indicated by Shannon Diversity Index (SDI) was greater than 4 in both endophyte-infected and endophyte-free tall fescue soil. In both types tall fescue soil, the prominent bacterial families were Planctomycetaceae, Balstocatellaceae_(subgroup_4), Chitinophagaceae, and Bacillaceae. In the case of soil fungal diversity, the SDI was overall low and ranged between 1.21 for endophyte-free and 1.27 for endophyte-infected tall fescue soil. The prominent fungal phyla were Basidiomycota and Ascomycota, and we observed a clear fungal community difference between endophyte-infected and endophyte-free soil at the phylum level. Moreover, endophyte-infected tall fescue soil showed a greater diversity at the genus level compared to endophyte-free tall fescue soil. In addition, plant-available soil phosphorus (P) is also influenced by the presence of endophytes in tall fescue. Conclusion Our results indicate that there is a tripartite relationship between tall fescue, the presence of fungal endophyte in the tall fescue, and the below-ground soil fungal communities. The dynamic of this three-way interaction perhaps contributes to the nutrient acquisition and stress tolerance by tall fescue possibly by recruiting a diverse array of potentially beneficial soil microbes.

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Effects of endophyte-infected tall fescue seed and red clover isoflavones on rumen microbial populations and physiological parameters of beef cattle1,2

Translational Animal Science ◽

10.1093/tas/txy147 ◽

2018 ◽

Vol 3 (1) ◽

pp. 315-328 ◽

Cited By ~ 2

Author(s):

Emily A Melchior ◽

Jason K Smith ◽

Liesel G Schneider ◽

J Travis Mulliniks ◽

Gary E Bates ◽

...

Keyword(s):

Tall Fescue ◽

Feed Efficiency ◽

Red Clover ◽

The United States ◽

Serum Prolactin ◽

Fescue Toxicosis ◽

Seed Type ◽

Final Body Weight ◽

Nonesterified Fatty Acids ◽

Tall Fescue Toxicosis

Abstract Lolium arundinaceum [(Darbyshire) tall fescue] toxicosis is responsible for substantial beef production losses in the United States, due to its negative effects on reproduction, growth, and feed efficiency. These effects are consequences of toxic alkaloids within tall fescue. Interseeding legumes, such as Trifolium pratense (red clover), into pastures has been shown to mitigate a portion of these effects. Clovers contain isoflavones, which may play a role in tall fescue toxicosis mitigation. The present study utilized 36 Angus steers to determine the effects of daily supplementation with a red clover-isolated isoflavone feed additive on physiological symptoms of tall fescue toxicosis and the rumen microbial environment over a 21-d period. Angus steers were initially stratified based upon their single nucleotide polymorphism genotype at the DRD2 receptor. Treatments were then randomly assigned in a 2 × 2 factorial arrangement within a completely randomized design, where treatment factors consisted of tall fescue seed type (endophyte-infected tall fescue seed vs. endophyte-free tall fescue seed) supplemented with and without the isoflavone additive. Steers that consumed endophyte-infected tall fescue seed had lower serum prolactin concentrations (P = 0.0007), average daily gain (ADG; P = 0.003), final body weight (BW; P = 0.004), and feed efficiency (P = 0.018) when compared with steers that consumed endophyte-free tall fescue seed. Serum insulin-like growth factor-1 (IGF-1) tended to be reduced with supplementation of isoflavones (P = 0.06) but was unaffected by seed type (P ≥ 0.10) and seed by treatment interaction (P ≥ 0.10). Isoflavones reduced serum glucose levels (P = 0.023), but neither seed type, isoflavones, or their interaction affected serum urea nitrogen (SUN), nonesterified fatty acids (NEFA), or insulin (P ≥ 0.10). Volatile fatty acid concentrations, dry matter intake (DMI), ruminal pH, and overall feeding behaviors were also unaffected by seed type or isoflavone treatments (P ≥ 0.10). Twenty-eight ruminal bacteria taxa shifted as a result of seed type or isoflavone treatment (P < 0.05). In this experiment, feeding isoflavones to Angus cattle did not completely mitigate all symptoms of fescue toxicosis. However, dose–response trials may aid future research to determine if dietary supplementation with isoflavones alleviates fescue toxicosis symptoms and promotes livestock growth and performance.

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