|Abstract or Summary
- Studies were conducted at the Squaw Butte Experiment Station during
two consecutive years to : (1) compare various internal indicators and
chromic oxide to estimate forage intake and fecal production, (2) compare
methods of producing slaughter weight steers using maximum quantities
of forage and minimum quantities of grain. Actual fecal output of
six 208 kg steers was correlated to chromic oxide (Cr₂0₃) estimates of
fecal output for collection times of 0700, 1200, 1700 and composite with
respective correlation coefficients of .63, .59, .80 and .79. The average
recovery of Cr₂0₃ was 94.05⁺- 3.91%. Estimates of forage intake
using lignin(L), crude fiber (CF), nitrogen (N) and indigestible dry
matter were correlated to actual forage consumption with respective coefficients
(r) of .92, .93, .96 and .89. No significant differences
were found between collection times of 0700, 1200, 1700 and the composite
sample for L, CF or N estimates of forage consumption. Estimates of
forage consumption were most accurately predicted by the L and CF methods.
Three trials conducted using a total of 129 Hereford or Hereford X
Angus steers evaluated the performance of steers on irrigated pasture and crested wheatgrass range during the growing phase (trials 1 and 2).
The steers were allotted to various finishing regimes from the growing
study. These included finishing on irrigated pasture, on range and in
the feedlot using two 40% roughage based rations for trial 1 and four
40% roughage based rations in trial 2. Trial 3 was conducted using fall
born steers which were either immediately sent to the feedlot and fed
two 38% straw based rations, put on irrigated pasture prior to going to
the feedlot or grazed on irrigated pasture, wintered on a 100% forage
diet of 2/3 alfalfa and 1/3 grass hay and then finished on crested wheatgrass
range the following spring. Faster (P<.05) gains were made on
crested wheatgrass range than on either alfalfa-fescue or clover-fescue
irrigated pastures. Steers finished on irrigated pasture and range made
greater daily gains than steers receiving the 40 roughage rations in the
feedlot of trial 1. The feedlot steers gained faster in trial 2 with
the range steers gaining the least (P<.05). In both trials the feedlot
groups had greater (P<.05) 24 hour carcass weights due to a longer feeding
period. Carcass grades were lowest for the alfalfa-fescue steers.
Overall desirability of the beef was greatest for the feedlot steers.
Daily gains were lowest (P<.05) for the fall born steers finished
on crested wheatgrass as compared to steers finished on 40% roughage rations.
Carcass weight, grade and marbling scores were not significantly
different between treatments. Less than 86 kg of barley was used to
produce slaughter weight steers from the crested wheatgrass range treatment.