730
Hematological and serum chemical profiles in lambs fed sericea lespedeza
Sericea lespedeza (SL) is a plant grazed or fed to small ruminants for parasite control. Condensed tannins in SL may lead to unintended consequences such as changes in production.The objective was to determine the effect of SL with or without molybdenum supplementation on changes in BW, hematology, and serum chemistry in lambs. Thirty Katahdin or Katahdin × Romanov lambs weaned in May (84 ±1.5 d of age; 27 ± 1.1kg) were blocked by BW, breed, and parasite resistance, and assigned randomly to be fed 900 g of 75% alfalfa pellets (CON; n = 10) or 75% SL pellets (n = 20) for 104 d. Supplements were isonitrogenous, ioscaloric, and similar in trace mineral concentrations. Within the SL group, half of the lambs were administered ~ 70 mg/lamb of sodium molybdate daily to ameliorate a reduction in serum molybdenum (SL+MO) observed previously. Lamb BW was obtained and blood collected every 14 d to determine hematological and serum chemical profiles. Data were analyzed using a mixed model with repeated measures. Mean packed cell volume, number of platelets, lymphocytes, monocytes, eosinophils, and hemoglobin were similar among diets (P > 0.10). White blood cell count (P < 0.05) and number of neutrophils (P < 0.001) were greater in CON than SL lambs. Red blood cell count was greater in CON and SL+MO than SL lambs (P < 0.03). However, mean corpuscular volume (P < 0.08) and corpuscular hemoglobin (P < 0.06) tended to be greater in SL than CON lambs (P < 0.08). Serum concentrations of albumin (P < 0.001) and aspartate aminotransferase (P < 0.003), were lower in SL than CON lambs. Serum concentrations of creatinine were greater for CON and SL+MO than SL lambs (P < 0.04), and total protein was greater in CON and SL than SL+MO lambs (P < 0.001). Serum concentrations of uric acid were similar among diets (P > 0.10). There was a treatment × time interaction for BUN in that values were greater in CON lambs between d 14 and 42 than SL fed lambs, and otherwise similar (P < 0.001). Lambs BW was similar among diets (P = 0.11). Since most hematological and serum chemical profiles were within a normal range, any changes in animal health or production associated with condensed tannins in SL observed in previous studies likely were not related to these variables examined.
Keywords:
Hematology, Lambs, Molybdenum, Sericea lespedeza