title: Characterization of toxicosis in sheep dosed with blossoms of sacahuiste (Nolina microcarpa).
abstract: To characterize more fully sacahuiste (Nolina microcarpa Watson) toxicosis in sheep and to evaluate benefits of supplemental Zn, sheep were dosed intraruminally with sacahuiste blossoms. In Trial 1, eight fine-wool sheep (47 +/- 2 kg BW) were fed alfalfa hay at 1% of BW daily and dosed intraruminally with inflorescences amounting to 1% of BW daily, in three portions per day, for 10 d. Four sheep were dosed intraruminally with aqueous ZnSO4 (30 mg of Zn/kg BW) daily for 3 d before initial sacahuiste dosing and on alternate days thereafter, and four sheep were untreated with Zn. Toxicosis was evident within 24 h after initial sacahuiste dosage, involving inappetence, depression, hypokalemia, hypophosphatemia, hyperbilirubinemia, and elevated serum enzymes (alkaline phosphatase, creatine kinase, lactate dehydrogenase, aspartate aminotransferase, and gamma-glutamyl transpeptidase). One sheep (untreated with Zn) died on d 3. Aqueous ZnSO4 alleviated inappetence and suppressed elevation of serum urea N and creatinine but did not suppress other changes in serum clinical profiles. In Trial 2, sacahuiste inflorescences were ruminally dosed into 12 fine-wool wethers (29 +/- 2 kg BW) in amounts equalling 0, .25, .50, .75% of BW per day, and chopped alfalfa hay was provided at 1.75% of BW per day for 14 d. Sacahuiste inflorescenses dosed at .75% of BW elicited severe toxicosis within 24 h, and dosage at .50 or .25% of BW per day increased (P = .12) serum bilirubin. Ruminal fluid pH, mean particle retention time, and particulate passage rate were not affected (P > .10) by sacahuiste, but ruminal fluid passage rate increased 1.6-fold (P < .10) and ruminal fluid volume decreased by 60% (P < .10) in sheep given inflorescenses amounting to .50% of BW daily. Sacahuiste inflorescenses dosed intraruminally at .75% of BW per day elicited ruminal impaction with severe hepatotoxicosis, and dosages amounting to .50% or .25% of BW per day caused similar trends.
authors.affiliation: Department of Animal and Range Sciences, New Mexico State University, Las Cruces 88003.
authors.forename: D L
authors.initials: DL
authors.lastname: Rankins
authors.forename: G S
authors.initials: GS
authors.lastname: Smith
authors.forename: T T
authors.initials: TT
authors.lastname: Ross
authors.forename: J S
authors.initials: JS
authors.lastname: Caton
authors.forename: P
authors.initials: P
authors.lastname: Kloppenburg
mesh_terms: D000818:Animals; D001663:Bilirubin / Q000097:blood; D001774:Blood Chemical Analysis / Q000662:veterinary; D001806:Blood Urea Nitrogen; D003404:Creatinine / Q000097:blood; D004435:Eating; D004573:Electrolytes / Q000097:blood; D004798:Enzymes / Q000097:blood; D005260:Female; D005772:Gastrointestinal Transit; D007700:Kinetics; D008297:Male; D010939:Plant Poisoning / Q000188:drug therapy / Q000209:etiology / Q000517:prevention & control / Q000662:veterinary*; D010947:Plants, Toxic; D012417:Rumen / Q000378:metabolism; D012756:Sheep; D012757:Sheep Diseases / Q000188:drug therapy / Q000209:etiology* / Q000517:prevention & control; D013431:Sulfates / Q000627:therapeutic use*; D013997:Time Factors; D017967:Zinc Compounds / Q000627:therapeutic use*; D019287:Zinc Sulfate
chemical_list: D004573:Electrolytes; D004798:Enzymes; D013431:Sulfates; D017967:Zinc Compounds; D019287:Zinc Sulfate; D003404:Creatinine; D001663:Bilirubin