@conference {51323, title = {Nutrient content and antiquality factors in Flourensia cernua at four growth stages}, booktitle = {Journal of Animal Science}, volume = {74 (Suppl. 1)}, year = {1996}, month = {1996}, pages = {199}, abstract = {

Tarbush (Flourensia cernua \ DC) is a rapidly increasing Chihuahuan Desert shrub. Use of livestock to control tarbush is being examined. Whole plants (n=120) were harvested to assess nutrient composition during 3 years across 4 growth stages: early (EG), midpoint (MG), late (LG) and senescent (SG) growth. Plants were air-dried then leaves were removed and freeze-dried. Nitrogen concentration was greatest for EG, lowest for SG, and no different between MG and LG (P \<.05; 3.95, 2.82, 2.77 and 2.62\% of DM for EG, MG, LG, and SG, respectively. Soluble N content was greater and ADIN content was lower for EG (P\<.05) than other stages. Insoluble N declined with advancing maturity (P\<.05). As a fraction of total N, insoluble N decreased and soluble N increased with maturity (P \<.05). IVDMD and was greater for EG than the other stages (P \<.05; 66.8, 61.0, 60.5 and 60.4\% of DM for EG, MG, LG and SG, respectively. Calcium concentration increased and P content decreased with maturity (P \<.05). Concentrations of NDF and ADF were lowest for EG (P \<.05) but did not differ among later growth stages. ADL content was least for EG and less for MG than LG or SG (P \<.05). Condensed tannin content tended (P \<.10) to increase with advancing season. Total phenolics concentration was least for EG (P \<.05)and not different among the other growth stages (6.6, 8.1, 7.9 and 7.6\% of DM for EG, MG, LG and SG, respectively). Nutrients and antiquality variables exhibited patterns normally associated with advancing phenology. Across seasons and years, tarbush was of reasonably high quality (3.0 \% N, 62.2 \% IVDMD, 20.8 \% NDF, 17.0 \% ADF, 1.51 \% Ca and 0.15 \% \ P, DM basis) and low in antiquality factors (0.1 \% ADIN, 6.6 \% ADL and .34 \% condensed tannins, DM basis), with the exception of total phenolics (7.6 \% of DM) and ether extract (13.6 \% of DM).

}, author = {Richard E. Estell and E.L. Fredrickson and Kris Havstad} }