Two experiments were conducted to evaluate the influence of a yeast-derived cell wall preparation (YCW) on forage intake and digestibility, ruminal fermentation characteristics, serum prolactin and prolactin stores, and milk production in beef cattle consuming high-alkaloid tall fescue straw. In Exp. 1, 16 Angus x Hereford ruminally cannulated steers (200...
Mycotoxins are food-borne toxins produced by molds which are commonly found on animal feeds of economic significance. Toxic doses of these compounds vary widely across livestock species, and even within a species when considered across all stages of development and production. This variation is due to the wide range of...
There have been many studies that describe the protective degradation or metabolism of potentially harmful plant toxins, such as, mimosine from Leucaena leuconcephala, pyrrolizidine alkaloids from tansy ragwort (Senecio jacobaea), oxalate and some mycotoxins by rumen microbes. There are many cases of plant-related toxicoses suffered by ruminant animals where there...
The pyrrolizidine alkaloids (PAs) and ergot alkaloids are known natural toxicants found in livestock forage. These alkaloids contribute to large economic losses in livestock throughout the world. An understanding of the mechanisms of toxicity and development of better diagnostic tools for better management practices was investigated. Variability exists in the...
The digestion responses and degradation of ergovaline and production of
lysergic acid in the rumen of sheep offered Neotyphodium coenophialum-infected
tall fescue straw at two ergovaline levels was investigated. Six crossbred wethers
(56 +1- 3 kg BW) were randomly assigned to one of two treatment groups in a
cross-over design....
We conducted two experiments evaluating perennial ryegrass straw as a forage source for ruminants. Experiment 1 evaluated digestion and physiological variables in steers offered perennial ryegrass straw containing increasing levels of lolitrem B. Sixteen ruminally cannulated Angus X Hereford steers (231 ± 2 kg BW) were blocked by weight and...
Endophytic fungi (A. coenophialum and A. lolii) which infect grasses produce ergot alkaloids that serve as the grasses' chemical defenses and enhance the vigor of the grass. Turf-type tall fescue with high endophyte levels has been deliberately developed to produce a greener, more vigorous, pest-resistant turf. Consumption of endophyte-infected grass...
