Blood metabolite and regulatory hormone concentrations and response to metabolic challenges during the infusion of mimosine and 2,3-dihydroxypyridine in alpine goats.
Sixteen Alpine wethers (average BW 35 +/- 2 kg) were used to evaluate the effect of continuous 48-h intravenous infusions of saline (CON), mimosine (MIM; 200 mg.kg.75.d-1), 2-hydroxy-3(1H)-pyridine (2,3-DHP; 200 mg.kg.75.d-1, or MIM+2,3-DHP (100 mg of MIM plus 100 mg of 2,3-DHP-kg.75.d-1) on hepatic function and selected blood metabolite and circulating hormone concentrations. Neither MIM nor 2,3-DHP affected plasma ammonia N, glucose, cortisol, or insulin concentrations over time (P > .10). Jugular plasma total protein concentration was greater in the MIM group (P < .07). Plasma triiodothyronine (P < .01) and thyroxine (P < .08) concentrations were higher in the goats receiving the MIM, 2,3-DHP, and MIM+2,3-DHP infusions than in the goats receiving the CON infusion. Plasma urea N concentration was decreased by MIM (P < .10) and MIM+2,3-DHP (P < .03) compared with the CON infusion. A Propionate Load Test was conducted at 24 to 28 h into the infusion to assess the toxins' effects on the liver's ability to increase circulating glucose concentrations in the presence of elevated propionate levels. The results indicated that neither 2,3-DHP nor MIM reduced the liver's ability to respond to a bolus dose of propionate (P > .10). Following a Urea Load Test, circulating ammonia N and glucose concentrations in the MIM, 2,3-DHP, and MIM+2,3-DHP treatments had lower peak values than that in the CON treatment (P < .01).(ABSTRACT TRUNCATED AT 250 WORDS)
al-Dehneh
A
A
E. (Kika) de la Garza Institute for Goat Research, Langston University, OK 73050.
Pierzynowski
S G
SG
Smuts
M
M
Sahlu
T
T
Fernandez
J M
JM
D000641:Ammonia / Q000097:blood; D000818:Animals; D001786:Blood Glucose / Q000032:analysis; D001798:Blood Proteins / Q000032:analysis; D001806:Blood Urea Nitrogen; D006041:Goats / Q000097:blood* / Q000502:physiology; D006854:Hydrocortisone / Q000097:blood; D007262:Infusions, Intravenous / Q000662:veterinary; D007328:Insulin / Q000097:blood; D008099:Liver / Q000187:drug effects / Q000502:physiology; D008297:Male; D008898:Mimosine / Q000008:administration & dosage / Q000097:blood / Q000633:toxicity*; D011725:Pyridines / Q000008:administration & dosage / Q000097:blood / Q000633:toxicity*; D011897:Random Allocation; D013974:Thyroxine / Q000097:blood; D014284:Triiodothyronine / Q000097:blood
D001786:Blood Glucose; D001798:Blood Proteins; D007328:Insulin; D011725:Pyridines; D014284:Triiodothyronine; D008898:Mimosine; D000641:Ammonia; C035877:2,3-dihydroxypyridine; D013974:Thyroxine; D006854:Hydrocortisone