|Taylor, Joshua - Bret|
Submitted to: Journal of Animal Science
Publication Type: Abstract Only
Publication Acceptance Date: 3/10/2004
Publication Date: 7/1/2004
Citation: Strickland, J.R., Obeidat, B.S., Taylor, J.B., Vogt, M.L., Loest, C.A., Sawyer, J.E., Reed, M.M., Krehbiel, C.R., Halalsheh, R.A., Chen, L. 2004. Effects of locoweed ingestion on serum constituents and rumen profiles of sheep.. Journal of Animal Science. Vol. 82, page 130, supplement 2, 7/1/04
Technical Abstract: Abstract: Thirteen mixed breed wethers (BW = 47.5 ' 9.3 kg) fitted with ruminal and duodenal cannulas were used in a randomized design experiment to evaluate the effects of locoweed on ruminal fermentation and serum constituents. Data were collected during 3 periods: pretreatment period (d -19 to d 0), treatment period (d 1 to d 20), and post-treatment period (d 21 to d 40). Treatments were 1) 0.2 mg, 2) 0.4 mg, and 3) 0.8 mg of swainsonine'kg BW-1'd-1. Blood samples were collected on d -19, -12, 0, 1, 7, 14, 21, and 26, and rumen samples were collected from 0 to 48 h in 4 h interval on d - 6, - 5, 15, 16, 39 and 40. In situ bags containing 5 g of assigned treatments were incubated in the rumen at 3, 6, 9, 12, 24, and 48 h on d - 3, - 2, 17, and 18 to evaluate nutrient digestion. Serum swainsonine was detected in all treatments during the treatment period and was highest (P < 0.05) for the 0.8 mg treatment. Activity of serum alkaline phosphatase (ALK-P) was greater (P < 0.05) for all treatments on d 7 versus d - 19, - 12, and 0. However, ALK-P activity on d 21 was similar (P = 0.13) to those observed on d - 19, - 12, 0. Activities of aspartate aminotransferase (AST) increased (P < 0.05) across the treatment levels on d 1, 7, and 14 and did not return to the baseline levels observed on d -19, -12, and 0. Concentrations of BUN, NEFA, and serum amino acids were not affected by treatments (P > 0.10). Also, concentrations of most of the VFA, except isobutyrate and propionate, were not affected (P > 0.10) by treatments. Isobutyrate was greater (P = 0.06) for the 0.4 mg than 0.2 and 0.8 mg treatment groups on d -6 and -5. Propionate concentrations were greater (P = 0.05) for 0.2 mg treatment than 0.4 mg treatment on d 39 and 40. Ammonia concentrations and ruminal pH were similar (P > 0.10) among treatments throughout the study. Dry matter digestion was similar (P > 0.10) among treatments throughout the study. However, treatment x time interaction was found in OM digestion at 48 h on d 17 and 18 and found to be greater (P = 0.01) for 0.4 mg than 0.2 and 0.8 mg treatment. Treatment x time interaction (P < 0.05) was found in ADF digestion on d 17 and 18; ADF digestion was higher (P < 0.05) for 0.2 mg than 0.8 mg treatment and was higher for 0.4 mg than 0.2 and 0.8 mg treatments at h 48. The results indicated that animals were intoxicated due to locoweed ingestion, but that locoweed ingestion did not greatly affect ruminal fermentation of nutrients by sheep.