Back to Search
Start Over
Steer responses to feeding soybean hulls and steroid hormone implantation on toxic tall fescue pasture.
- Source :
-
Journal of animal science [J Anim Sci] 2010 Nov; Vol. 88 (11), pp. 3759-66. Date of Electronic Publication: 2010 Jul 23. - Publication Year :
- 2010
-
Abstract
- Crossbred steers were grazed in the spring and early summer on endophyte-infected (Neotyphodium coenophialum), Kentucky-31 tall fescue (Lolium arundinaceum) pastures to evaluate effects and interactions of feeding pelleted soybean hulls (PSBH) and steroid hormone implants (SHI) on steer performance, serum prolactin, and hair coat ratings (HCR). Steers were stratified by BW for assignment to six 3.0-ha toxic tall fescue pastures. With or without daily PSBH feeding, treatments were assigned randomly to pastures as the main plot treatment in a split-plot design. Pelleted soybean hulls were group-fed to provide 2.3 kg(steer·d(-1)) (as fed). With or without SHI (200 mg of progesterone and 20 mg of estradiol) treatments were randomly assigned as the subplot treatment to 2 steer subgroups within each pasture. Sixty-four steers were grazed for 77 d in 2007, and 60 steers were grazed for 86 d in 2008. Pasture forage mass declined linearly over time, but the rate of decline was greater (P = 0.001) in 2007 than in 2008. Pasture forage mass was never below 2,300 kg of DM/ha in either year. Average daily gain for steers on the combined PSBH and SHI treatments was greater (P < 0.01) than for those on the PSBH-only, SHI-only, and control (no SHI, no PSBH) treatments. Average daily gain for the PSBH-only steers was greater (P < 0.01) than for SHI-only and control steers and tended (P = 0.063) to be greater for SHI-only than for control steers. Steroid implants did not affect (P = 0.826) serum prolactin concentrations; however, prolactin concentrations in PSBH steers, with or without SHI, were increased (P = 0.01) 2-fold over SHI-only and control steers. Feeding PSBH and SHI treatments both reduced (P < 0.05) the percentage of steers with rough HCR, and a greater percentage of steers fed PSBH tended (P < 0.076) to have sleek hair coats. An economic analysis was conducted, which determined that costs of additional ADG with PSBH feeding were below breakeven costs over a wide range of PSBH costs and cattle prices. Breakeven costs for PSBH-only treatment for a range of cattle prices of $1.80 to $2.40/kg of BW were less than $120/t, whereas with PSBH feeding combined with SHI the breakeven cost was less than $240/t. Results indicate that steers grazing endophyte-infected tall fescue can be fed PSBH and implanted with steroid hormones to cost effectively increase ADG and that feeding PSBH can increase serum prolactin concentrations and induce some shedding of rough hair coats.
- Subjects :
- Animal Feed analysis
Animal Feed microbiology
Animal Nutritional Physiological Phenomena
Animals
Body Composition
Diet veterinary
Drug Implants economics
Estradiol administration & dosage
Estradiol economics
Male
Mycoses
Neotyphodium
Poaceae growth & development
Progesterone administration & dosage
Progesterone economics
Prolactin blood
Time Factors
Weight Gain drug effects
Cattle growth & development
Estradiol pharmacology
Poaceae microbiology
Progesterone pharmacology
Glycine max
Subjects
Details
- Language :
- English
- ISSN :
- 1525-3163
- Volume :
- 88
- Issue :
- 11
- Database :
- MEDLINE
- Journal :
- Journal of animal science
- Publication Type :
- Academic Journal
- Accession number :
- 20656966
- Full Text :
- https://doi.org/10.2527/jas.2009-2536