An experiment was conducted to determine the feasibility of winter grazing pregnant Hereford cows on fescue prairie. The experiment was replicated over a 4-yr period (1988–1991, n = 4) and utilized a 2 × 2 factorial design representing fall grazing (September to November) on annual pasture (winter wheat and corn) or fescue prairie; and winter grazing (November to the end of February) on fescue prairie or feeding in a drylot. The cows weighed an average of 519 kg and had an average of 4.4 mm of backfat in late May when summer grazing on fescue prairie began and 7.2 mm of backfat at the beginning of fall grazing. Measurements of cow backfat and cow weights at each feeding change indicated that during the fall grazing period, average daily gain (ADG) was −0.43 kg and change of backfat was −1.0 mm on fescue prairie compared with + 0.12 kg and + 0.9 mm, respectively, on annual forage. Fall grazing of annual forages had no effect on the ADG of cows in winter but resulted in higher backfat after the winter feeding period (5.3 vs. 4.1 mm, P = 0.009). In later winter, cows kept on fescue prairie over the entire grazing period averaged 3.5 mm of backfat, while the cows grazed on annual forages in the fall and wintered in the drylot averaged 5.7 mm. Cows may be kept on fescue prairie in fall and winter. However, feed supplementation is needed to achieve optimal condition at calving. Fall grazing of annual forages may allow cows to maintain their body weight on fescue prairie, minimizing costly feed inputs prior to calving. Key words: Cows, calves, annual forage, backfat, fall grazing
A multi‐sector mathematical programming model of Canadian agriculture (CRAM) is employed to determine the rate of return to yield‐increasing research on wheat conducted during 1962–91. The estimated internal rate of return to yield‐increasing research ranged between 27% and 31% for the low wheat price scenarios. It was higher at 34–39% for the high wheat price scenarios. Producers captured 80–90% of the benefits. The results support the magnitude of estimated economic benefits reported in previous studies.
Fnenze, B. S. eNo Sot',turnrelor, T. G. 1985. Breakeven hauling distances for beef feedlot manure in southern Alberta. Can. J. Soil Sci. 65: 68'l-693.The economics of hauli{rg manure as a substitute for commercial fertilizer in the production of cultivated crops was investigated using a computer model that accommodates variables such as hauling distance, machinery complement, hauling speed, labor use, spreading time, and crop response. Machinery complement and labor requirements were defined and budgeted for three farm-feedlot scenarios, namely: a very large farm-feedlot (> 1000 head capacity), a large farm-febdlot (500-1000 head capacityl), and a small farm-feedlot (< 500 head capacity). Results indicate that manure, vdlued
Lifetime productivity of fescue grasslands (Festuca scabrella var. campestris Rydb.) is enhanced by fall and winter grazing as opposed to summer grazing. However, forage quality is below the maintenance requirements of cattle and weathering losses will reduce available forage. Cows tend to lose weight and backfat prior to calving if their only feed source through fall and winter is native grassland. Maintaining adequate cow condition for spring calving is important to prevent long term losses associated with reduced calf birth weights, lower cow fertility and reduced cow longevity. Cow condition can be improved by having cows graze annual forage in the fall or by supplementing the cows with grain screenings. Alternatively, cows can be fed in a feedlot prior to calving to restore body condition lost in grazing native grassland in the fall and winter. Results from a 3-year experiment showed that winter wheat pasture grazed in the fall, supplemented with grain screenings was generally the least expensive alternative (ranging from $70 cow -1 at low barley prices approaching $0.052 kg -1 , to $97 cow -1 at high barley prices approaching $0.175 kg -1 ) for maintaining cow condition prior to calving. Restoring cow condition in a feedlot prior to calving was less expensive than provision of fall annual pasture when grain prices were low (barley price below $0.14 kg -1 ).
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.