Submitted to: Journal of Animal Science
Publication Type: Abstract Only
Publication Acceptance Date: 3/15/2007
Publication Date: 7/9/2007
Citation: Phillips, W.A., Northup, B.K., Venuto, B.C. 2007. Intensive short duration grazing of fescue pastures to extend the grazing season of winter wheat. Journal of Animal Science.85(1):498-499 Interpretive Summary: ABSTRACT ONLY
Technical Abstract: Over 10 million ha of winter wheat are planted in the southern Great Plains (SGP) each year, and serves as the major forage resource for millions of stocker calves before they enter the feedlot for finishing. If more BW gain is produced during the stocker phase, then the amount of feed grains used during the finishing phase will be less. This experiment examined the feasibility of using a perennial cool-season grass to extend the period of grazing for winter wheat and produce more kg of BW/calf. Three, 1.7-ha 2-yr old tall fescue (Festuca arundinarea Var. Jessup ‘Max-Q’™) pastures were used for short periods of intensive grazing in the spring (S) and fall (F). The pastures were fertilized each year with 56 kg of N/ha (F and S) and 22 kg of P/ha (F only). Calves (n= 215; 280 ±32 kg BW) used were predominately British breeds, less than 12 months of age. A different set of calves were used in each grazing period (3 S and 3 F periods). Standing crop available for grazing at the start of the grazing period was used to determine the stocking rate. Data were analyzed using a mixed model to determine the impact of grazing period on stocker performance with pasture serving as the experimental unit and year (n=3) was random. Pastures produced more (P < 0.01) forage in the S than in the F (4490 vs. 2230 kg DM/ha) and the stocking rate was greater (P < 0.01) in the S than in the F (2290 vs. 1450 kg BW/ha). Length of the grazing period and the number of grazing d/ha were not different (P > 0.10) between S (35 d and 259 d/ha) and F (39 d and 245 d/ha), but ADG was greater (P < 0.01) during the S as compared to the F (1.02 vs. 0.57 kg). As a result, BW gain/ha were greater (P < 0.01) during the S than in the F (264 vs. 140 kg/ha). Under intensive short-duration grazing management, fescue pastures can be used to extend the traditional SGP winter wheat grazing season and would result in greater BW gain/calf. Shifting land resources from wheat to fescue production did not decrease gross returns to the enterprise but did change the month of the year calves would be purchased and sold.