Lactation in mice fed endophyte-infected tall fescue seed.
This study was conducted to assess the effects of endophyte-infected Acremonium coenophialum tall fescue (KY-31) seed (80% infected) on lactation in CD-1 dams and suckling performance of pups as measured by pup survival and growth rates. Twenty-four pairs of mature CD-1 mice were randomly allocated to four dietary treatments: 1) 100% mouse chow ad libitum; 2) 40% endophyte-infected tall fescue seed and 60% mouse chow (w/w); 3) reduced intake (100% chow), adjusted daily to the intake level of Treatment 2; and 4) 60% infected tall fescue seed and 40% chow. The mice were preconditioned on their respective diets for 100 d prior to 96 h of cohabitation between pairs of males and females. At parturition the litters were removed, and each dam was given a litter of six pups of equal weight, size and sex ratio to suckle for 15 days. All pups given to all the dams were born to other mice that were not part of the study and had not been exposed to endophyte-containing diets. Dams and litter weights were measured daily for 15 consecutive days. The combined body weight measurements of litters from dams fed the tall fescue containing diets (Treatments 2 and 4) were significantly lower (2.07 +/- 0.41 g/d) than that of litters from dams fed the chow containing diets (Treatments 1 and 3) during the suckling trial (P<0.05). Similarly, nine of ten (90%) dams fed the chow containing diets maintained five or more pups (5.5 +/- 0.2) throughout the study as compared to five of nine (55.6%) dams fed the tall fescue containing diets that maintained less than five pups (4.5 +/- 0.2).
Reproductive responses in male rats fed extracts of fescue seed infected by the endophytic fungus Acremonium coenophialum.
This study was undertaken to determine whether a methanol extract of endophyte-infected tall fescue seed contained the factor(s) that were responsible for the decrease in male reproductive potential when rats were fed toxic tall fescue seed. Twenty-four Sprague-Dawley male rats (ca. 225 g.) were randomly allocated to one of three dietary treatments containing 50% (w/w) rodent chow and 50%: (1) noninfected tall fescue seed; (2) noninfected tall fescue seed treated with concentrated methanol effluent from serial methanol extraction of infected seed; and (3) the extracted seed residue of seed that was greater than 95% infected by Acremonium coenophialum. Parameters assessed were testicular weight, epidydimal weight, parenchymal weight, progressive sperm motility, sperm motility, sperm count and daily sperm production potential. Significant reduction (P less than 0.05) for feed intake, average daily gain, testicular weight, epidydimal weight and daily sperm production potential were observed for treatment 2. These data suggest that the serial methanol extract contains the factor(s) responsible for the lowered reproductive potential in male rats. The extract contained 15,578 micrograms/ml of pyrrolizidine alkaloids and only trace amounts of ergopeptides. These results suggest that N-formyl and N-acetyl loline may play an important role in the fescue toxicity noted in the exposed rats.
Comparative Value of Kentucky Bluegrass, Kentucky 31 Fescue, Orcard Grass, and Bromegrass as Pastures for Milk Cows. I. How Kind of Grass Affected Persistence of Milk Production, TDN Yield, and Body Weight
persistency of milk production (98.3%), followed in order by Kentucky 31 fescue-ladino (89.2%), Kentucky bluegrass-ladino (87.2%), and a straight stand of Kentucky 31 fescue (81.4%). The straight fescue was fertilized twice yearly with 100 lb. of ammonium nitrate. Under these conditions the fescue alone produced yearly the most TDN per acre (2,327 lb.), whereas the three other pastures yielded about the same, varying from ],726 to 1,789 lh. per acre. The loss in stands of ladino clover with the fescue aml bluegrass, plus the volunteer introduction of a light stand of white clover in the "straight" rescue, probably altered the results secured from the experiment. Pratt and IIayncs (8) of the Ohio Station were the first to report experiments with Kentucky 31 rescue as pasture for milk cows and dairy heifers. In 1948 they seeded rescue with alfalfa and ladino clover and secured a stand of mostly rescue and ladino with a scattering of alfalfa. Jersey heifers grazing this pasture in 1949 made gains of 0.2 to 0.4 lb. per head daily as compared with gains of 1.7 lb. daily when grazing' bluegrass-ladino pasture or meadow crop mixtures. In a reversal experiment they found that milk cows ate nlore hay, produced less milk, and lost more weight while grazing Kentucky 31 fescueladiuo than when on the bluegrass-ladino pasture. In another experiment their cows produced more milk while fed in dry lot than while on fescue-ladino pasture. In a 1953 trial conducted at ]Iamilton, Ohio, Pratt and Davis (7) reported that cows secured 49% more TDN from the bluegrass-ladino than from rescue