Performance, forage utilization, and ergovaline consumption by beef cows grazing endophyte fungus-infected tall fescue, endophyte fungus-free tall fescue, or orchardgrass pastures1

Abstract

Two 120-d trials (May to September, 1988 and 1989) determined the effects of grazing tall fescue (two varieties) or orchardgrass on forage intake and performance by beef cows. Each summer, 48 cow-calf pairs grazed endophyte-infected Kentucky-31 tall fescue (KY-31), endophyte-free Mozark tall fescue (MOZARK), or Hallmark orchardgrass (OG) pastures (16 pairs/treatment). Forage OM intakes and digestibilities were determined during June and August each year. Cow and calf BW and milk production were determined every 28 d. During June of both years, OM intakes did not differ (P greater than .10) among treatments. During August of 1988, intakes were 18% lower (P less than .05) by KY-31 cows (1.6% of BW) than by MOZARK or OG cows (average 1.95% of BW); however, no differences (P greater than .10) were measured in August of 1989. Estimates of ergovaline consumption during June from KY-31 were between 4.2 (1988) and 6.0 mg/d (1989), whereas August estimates were between 1.1 (1988) and 2.8 mg/d (1989). Ergovaline in MOZARK estrusa was below detection limits, except in August of 1989. Cows that grazed KY-31 lost three times (P less than .01) more BW than cows that grazed MOZARK or OG (42 vs 9 and 13 kg, respectively). Milk production by KY-31 cows was 25% lower (P less than .01) than that by cows that grazed MOZARK or OG (6.0 vs average of 8.0 kg/d). Similarly, slower (P less than .01) calf gains were noted for KY-31 than for MOZARK or OG (.72 vs .89 and .88 kg/d, respectively). Cows grazing KY-31 experienced accelerated BW loss and reduced milk production and weaned lighter calves than did cows grazing MOZARK or OG. Decreased performance was not explained by consistently reduced forage intakes; hence, altered nutrient utilization was suspected.

Physiological effects of endophyte-infected perennial ryegrass straw on female camels in the Middle East

“…This is in contrast to a study on pregnant cows where pre-and post calving body weights were not affected by increasing lolitrem B concentrations (Fisher et al, 2004). The phenomena of decreased weight gain has been seen in numerous other studies of livestock consuming endophyte-infected grasses containing the alkaloid ergovaline, a condition called "summer slump" and is most commonly associated witht ergovaline in tall fescue (Neotyphodium coenophialum) (Peters et al, 1992). The perennial ryegrass straw used in this study did contain ergovaline at approximately onethird the level in ppb of lolitrem B.…”

Anti-quality factors associated with alkaloids in eastern temperate pasture

“…At 100 days postpartum, primiparous beef cows grazing E+ tall fescue had 50% lower milk production than those grazing E-tall fescue ). Beef cows grazing E+ KY 31 tall fescue had a 25% reduction in milk production compared to cows grazing E-Mozark tall fescue or orchard grass, (6.0 and 8.0 kg/day, respectively) (Peters et al 1992). Calf growth associated with nursing cows grazing E+ tall fescue was also significantly reduced compared to the other 2 groups.…”

Preference by sheep for endophyte-infected tall fescue grown adjacent to or at a distance from alfalfa

“…Ergovaline at concentrations of 500 to 800 ppb causes clinical disease in sheep (Hovermale and Craig, 2001). Although ergovaline in FA was below these levels, sub-clinical concentrations of alkaloids in tall fescue cause measurable changes in livestock performance (Peters et al, 1992), which affect foraging behavior and welfare of sheep (Catanese et al, 2014).The five animals that regularly (on at least 5 days each) had diarrhea, all lost weight, and of these animals, four selected >60% of their diet as FA. Animals satiate on specific foods, a result of interactions among primary and secondary compounds (Provenza, 1996), and they typically show cyclic patterns of intake of plants that contain secondary compounds (Pfister et al, 1997).…”