Trial Location: Fairview Research Farm, NW-5-82-3-W6 on RR #35, MD of Fairview
Research Coordinator: Dr. Akim Omokanye
From: Peace Country Beef & Forage Association 2015 Annual Report
In Alberta, oats have become a reliable source of conserved forage for over-wintering beef cattle. In an effort to continue to identify oat varieties that have superior forage production in the Peace, PCBFA tested a few oat varieties in Fairview in 2015. The test was part of the Regional Silage Variety Trials (RSVTs) testing program, which includes testing of new barley varieties as they become available for adaption, forage yield and quality across Alberta. In addition to the findings presented here from our trial, the results from the RSVTs across the different trial sites in the province will also be reported in the Alberta Seed Guide (www.seed.ab.ca).
Methods
The study site was at Fairview Research Farm (NW5-82-3W6) on RR #35, MD of Fairview. The site used was seeded to alfalfa and had been hayed for more than 10 years. Prior to seeding, soil tests at 0-6” soil depth done at Exova laboratory (Edmonton) showed an organic matter of 3.0 % and a pH of 6.9. The site was sprayed with Roundup the fall before and worked in the spring before seeding .
Five (5) oat varieties were arranged in a randomized complete block design in 4 replications in small plots. Seeding was done on May 25 with a 6-row plot drill at 9 inch row spacing. Fertility according to soil test recommendations for balanced crop nutrition was 200 lb N + 96 lb P + 62 lb K + 75 lb S, applied at seeding. Roundup was used for burn off. In-crop spraying was done with 0.44 L/ha Prestige A + 1.98 L/ha Prestige B. The oat varieties tested were:
CDC Baler – forage oat
AC Morgan –milling oat, but commonly used for silage or green feed
AC Mustang – feed oat
CDC SO-1 (Super Oat number 1) – feed/forage oat
CDC Haymaker - new forage oat
Forage harvest was done on August 6 at the late milk stage. Four rows per plot were harvested by hand and weighed fresh. Sub-samples (about 500 grams per plot) were dried and later reweighed for dry matter (DM) content and DM yield estimation. Forage samples were analyzed for quality using standard procedures for wet chemistry by Central Testing Laboratory Ltd., Winnipeg.
Fairview was generally dry in 2015, and grasshopper infestation was very high. Moisture received from seeding to harvest was 4.32 inches, with 1.19 inches received from August 3 to 5, which was just a few days before forage harvest.
Results
Forage DM yield (Figure 1)
Mustang oats had the highest forage DM yield (6928 lbs/acre), followed by both CDC Baler and Morgan oats, which had similar DM yields (2.87 ton/acre). CDC SO-I had the least DM yield (4888 lbs/acre). The ability of AC Mustang to produce more DM than other varieties probably has to do with their adaptation to growing conditions in the Peace.
Forage Quality
Protein & Minerals - The forage protein (CP) content of oat varieties tested varied from 10 to 12% CP. The forage Ca was highest for CDC Baler. Both CDC SO-I and AC Mustang had higher forage P than other oat varieties. The forage Mg content was in order of CDC Baler >CDC SO-I > AC Mustang > CDC Haymaker/AC Morgan. Forage K content varied from 1.23% K for CDC SO-I to 1.36% K for CDC Haymaker. Both CDC Baler and CDC SO-I had higher Na than other oat varieties.
The requirements for protein (CP), Ca, P (except for CDC Haymaker), Mg, K and Na of a dry gestating beef cow (mid & late-pregnancy stages), have been met by all oat varieties tested here.
For a lactating beef cow, all oats (except AC Morgan, which slightly fell short) had sufficient protein for this category of cow. Only CDC Baler had adequate Ca for a lactating cow. All varieties fell short of meeting the P requirements of a lactating cow. All oat varieties exceeded the requirements of Mg, K and Na of a lactating cow.
The forage energy (TDN) content was generally above 60% for all oat varieties. This shows that all oats tested had adequate TDN for a dry gestating cow, which requires 55% TDN in the second trimester and 60% TDN in the third trimester. For a lactating cow which requires 65% TDN, most oat varieties would need some energy supplementation.
A mature beef cattle requires ME in the range of 2.23 to 2.54 mcal/kg and all oats tested fell within this range. Similarly, all oats were within the suggested 0.97-1.10 Mcal/kg of NEM for a cow in dry gestation stage and 1.19-1.28 Mcal/kg NEM during lactation. For growing and finishing calves, which require 0.53-1.37 Mcal/kg of NEG, all oats were within this range.
Conclusion— The AC Mustang oat variety yielded the most forage dry matter compared to the other oat varieties. AC Mustang also had good forage quality including protein and energy. The ability of AC Mustang to produce more DM than other varieties probably has to do with their adaptation to growing conditions in the Peace.