Life Sciences Commons^™

A Mathematical Model Of Forage-Based Post-Weaning Growth Of Beef Cattle, David Glenn Keltner

Doctoral Dissertations

Four three-year experiments were conducted using 1. 2 ha pastures to evaluate the productivity of various forage species combinations and the performance of stocker steers grazing them. Forage systems used were (1) Common bermudagrass (Cynodon dactylon L. var. dactylon) + 112 or 224 kg N/ [CB] ; (2) Common bermudagrass overseeded with high endophyte (Acremonium coenophialum Morgan-Jones & Gams) tall fescue (Festuca arundinacea Schreb.), ladino clover (Trifolium repens L.) and Kobe lespedeza (Lespedeza striata (Thunb.) H & A) [CB + HF + LEG]; (3) HF + 67 kg N/ha [HF]; (4) HF + LEG; (5) Low endophyte …

Fescue Toxicity In Sheep: I. Effects Of Acremonium Coenophailum On Total Splanchnic And Peripheral Flux Of Energy Metabolites And Their Regulatory Hormones In Sheep. Ii. Hepatic Mixed-Function Oxidase Activity Of Sheep Fed Fungus-Infested Fescue, Ergotamine Tartrate, Cimetidine And Metoclopramide, Kenneth Patrick Zanzalari

Doctoral Dissertations

Mature ewes were equipped with catheters in the portal, hepatic, mesenteric and femoral veins and femoral artery. Blood flows were measured by infusing a 1.5% solution of para-aminohippurate into the mesenteric vein at .764 ml/min. Net fluxes of metabolites were calculated by multiplying veno-arterial differences by tissue blood flows.

Study 1. Twenty experiments were conducted on five ewes to determine the effects of fungus-infested fescue hay on energy nutrients and regulatory hormone net fluxes. Ten experiments were conducted for each a fungus-free and fungus-infested fescue hay diet. Fungus-infested hay decreased arterial concentrations of acetoacetate and B­ hydroxybutyrate by 15 and …