title: Toxicity of endophyte-infected ryegrass hay containing high ergovaline level in lactating ewes.
abstract: The symbiotic association of var. (formerly named ) with perennial ryegrass () leads to the production of ergovaline (EV) and lolitrem B (LB) that are toxic for livestock. The objectives of this study were to determine the effects of feeding endophyte-infected ryegrass (SE+) hay on 16 lactating ewes (BW 80 ± 10 kg) in comparison with endophyte-free ryegrass (SE-) hay to investigate the putative mechanisms of action of EV and LB and to evaluate their persistence in milk and animal tissues. The mean EV and LB concentrations in SE+ hay were 851 and 884 μg/kg DM, respectively, whereas these alkaloids were below the limit of detection in SE- hay. No effect of SE+ was observed on animal health and skin temperature whereas prolactin decreased and significant differences between hays were observed from d 7 to 28 of the study ( < 0.03) but had no effect on milk production. Hematocrit and biochemical analyses of plasma revealed no significant difference between SE+ and SE-, whereas cortisol concentration differed significantly on d 28 ( = 0.001). Measurement of oxidative damage and antioxidant enzyme activities in plasma, liver, and kidneys revealed a slight increase in some enzyme activities involved in defense against oxidative damage in the SE+ fed ewes. Slight variations in the activities of hepatic and kidney flavin monooxygenase enzymes were observed, whereas in the kidney, glutathione -transferase activity decreased significantly ( = 0.002) in the SE+ fed ewes, whereas uridine diphosphate glucuronosyltransferase activity increased ( = 0.001). After 28 d of exposure of ewes to the SE+ hay, low EV and LB concentrations were measured in tissues. The highest concentration of EV was observed in the liver (0.68 μg/kg) whereas fat contained the highest concentration of LB (2.39 μg/kg). Both toxins were also identified at the trace level in milk.
authors.forename: N
authors.initials: N
authors.lastname: Zbib
authors.forename: C
authors.initials: C
authors.lastname: Repussard
authors.forename: D
authors.initials: D
authors.lastname: Tardieu
authors.forename: N
authors.initials: N
authors.lastname: Priymenko
authors.forename: C
authors.initials: C
authors.lastname: Domange
authors.forename: P
authors.initials: P
authors.lastname: Guerre
mesh_terms: D000821:Animal Feed / Q000032:analysis; D000818:Animals; D004032:Diet / Q000662:veterinary; D060026:Endophytes / Q000378:metabolism*; D004879:Ergotamines / Q000737:chemistry / Q000633:toxicity*; D005260:Female; D026121:Indole Alkaloids / Q000737:chemistry / Q000633:toxicity*; D007774:Lactation / Q000187:drug effects; D008129:Lolium / Q000382:microbiology*; D008892:Milk / Q000737:chemistry; D009183:Mycotoxins / Q000737:chemistry / Q000633:toxicity*; D018384:Oxidative Stress; D011388:Prolactin / Q000097:blood; D012756:Sheep; D012757:Sheep Diseases / Q000139:chemically induced*
chemical_list: D004879:Ergotamines; D026121:Indole Alkaloids; D009183:Mycotoxins; C076760:ergovaline; C033673:lolitrem B; D011388:Prolactin