Research Coordinator: Dr. Akim Omokanye
Location: Fairview Research Farm
From: Peace Country Beef & Forage Association 2019 Annual Report
Feed and forage-type barley varieties can be grown for swath grazing, greenfeed or silage. Barley can also be included in cover crop cocktail mixtures for livestock production. In the Peace Country, barley is the preferred cereal crop for silage. Barley produces the best combination of yield and quality for silage of any of the cereals commonly grown within the region. Every year, PCBFA takes part in the Regional Silage Trials (RSTs) for different crop species and varieties. The RSTs generate and provide scientifically sound variety performance information to livestock producers, industry and extension specialists. In addition to the findings of the barley variety trial from Fairview being presented in this report, the results from the RSTs across the different trial sites in the province will also be reported in the Alberta Seed Guide (www.seed.ab.ca).
Objective
Identifyprovide barley varieties with improved forage yield and quality for greenfeed and silage for livestock production.
Methods
Experimental Site: Fairview Research Farm (NW-5-82-3-W6M) on RR #35, MD of Fairview.
Previous Crop: The previous crop at the site before testing barley varieties for forage production was an alfalfa hay crop for several years until the fall of 2017. This was unseeded (chemical fallow) in 2018.
Land Preparation: In the fall of 2018, the site was sprayed with Roundup at 1.0 L/acre (to kill the existing alfalfa-dominated vegetation) and plowed. The site was disced & harrowed in the spring of 2019.
Soil analysis was completed in the fall of 2018 from a soil depth of 0-6” which showed an organic matter content of 8.2%, pH of 6.2 and an electrical conductivity of 0.21 ds/m. The soil test reports showed 10 lbs N/acre, 14 lbs P/acre, 485 lbs K/acre, and 9 lb S/acre.
Spring soil moisture at seeding: 12.4% (0-5 cm soil depth) and 14.1% (0-20 cm soil depth).
Spring soil temperature a Seeding: 9.19°C (0-5 cm soil depth) and 7.79°C (0-20 cm soil depth).
Experimental Design: 16 treatments in Randomized Complete Block Design with 4 replications.
Treatments: 16 barley varieties (ten 2-row & six 6-row varieties) were seeded.
Two-row barley varieties
1. CDC Austenson (check) – rough awn feed barley variety, short and string straw
2. CDC Cowboy – forage barley, tall, responds well to low moisture and fertility
3. TR17639 – feed and forage
4. Canmore – general purpose barley, with applications for the feed
5. CDC Maverick – smooth awns, forage barley
6. Claymore – feed barley
7. CDC Coalition – feed barley
8. Altorado – feed barley, a fair to good resistance to drought conditions.
9. CDC Bow – malting-type barley
10. CDC Fraser – malting-type barley
Six-row barley varieties
1. SUNDRE – feed barley for grain and forage
2. SR17519 – feed and forage
3. SR17515 – feed and forage
4. AB Advantage – a new Smooth awned feed and forage barley
5. Amisk – semi-dwarf, semi-smooth awned, feed barley
6. AB Cattlelac – a new semi-smooth awned feed variety
Seeding Rate and Date: A plant population of 300 plants/m2 (27.8 plants/ft2) was used. Seeding date was on May 23.
Seeding Method: The seeds were sown using a Fabro plot drill equipped with disc-type openers on 9” row spacing. Six rows that were 8 m long were sown per plot. Seeding depth was 0.75”.
Fertility for an average barley yield (actual lbs/acre) was applied at: 89 N + 39 P + 0 K + 13 S. No K was applied as the soil test reports showed optimum levels of K for barley production for the year.
Spraying: Pre-emergent herbicide with StartUp (Glyphosate, 540 grams acid equivalent per litre, present as potassium salt) was applied at 0.67 L/acre. StartUp is a water soluble herbicide for non-selective weed control. In-crop herbicide application was with Prestige A (170 mL/acre) + Prestige B (800 mL/acre).
Harvesting for forage dry matter (DM) yield determination was done on August 14 when the barley varieties were at the soft dough stage. Forage samples were shipped to A & L laboratory, Ontario for forage quality determination. Plant height was taken a day before the varieties were harvested. Notes were also taken on plant lodging one day prior to harvest.
Rainfall received from seeding to forage harvest for the barley varieties was 159.9 mm (or 6.30”) compared to 167.2 mm (6.58”) for the long-term average of the same period.
Results and Implications
Plant Height
Both CDC Cowboy and CDC Maverick grew taller than other barley varieties (Table 1). Even with 3 feet or more in plant height, no lodging (perfect standability) was observed for all.
Forage Dry Matter Yield
The varieties were harvested at the soft dough stage and the varieties generally were in the 65-70% moisture content range that is required for silage (Table 1) .
In the present study, CDC Maverick barley produced lower forage DM than most barley varieties tested. Also, compared to PCBFA previous studies in a comparable environment, this year, CDC Maverick barley produced lower forage DM than trials (See previous PCBFA Annual Reports). What is responsible for the lower forage DM yield from CDC Maverick barley than most of the varieties tested this year is difficult to explain. It is possible that the amount of rainfall received this year from seeding to harvest, particularly in July and August (before harvest) was on the high side for CDC Maverick barley variety.
The Technical Bulletin published by SeCan in 2015 (https://www.chinridge.com/technical-bulletins/CDC-Maverick-2015.pdf) did indicate that CDC Maverick is best suited for dryland applications and ideal for areas with lighter soils, but will produce top forage yields under almost all conditions across Western Canada. So, it is possible that the amount of rain received and its distribution may not have been in favour of CDC Maverick barley this year. It is important to note that CDC Maverick barley has always ranked higher in Alberta variety silage trials. With it's smooth awn, CDC Maverick is more palatable to cattle than barley varieties with a rough awn and can be used for swath grazing as well as silage.
Forage Crude Protein Content and Crude Protein Fractions
Altorado, a 2-row feed variety had the highest forage crude protein (CP) with 13.1% CP, followed by both CDC Austenson and Canmore varieties with 12.3% CP each (Table 1). All varieties generally had 10% CP or more, indicating that they all had adequate CP for a dry gestating beef cow (in mid-pregnancy and late pregnancy). For mature beef cows that require 11% CP during lactation, most varieties conveniently met this requirement as well.
For the CP fractions, both forage soluble protein (Sol CP) and undegradable intake protein (UIP) were not statistically affected by barley varieties tested here (Table 1). It is important to note that the Sol CP is most readily available to animals. The UIP bypass protein (commonly called by-pass protein or rumen undegradable protein (RUP)) is the fraction of protein that is resistant to degradation by rumen microbes. This fraction of protein is often valued because it can be absorbed in the small intestine. The magnitude of UIP for any particular diet or feed ingredient is dependent upon both the feed itself and the animal to which it is fed. In particular, when feed intake is low (e.g. dry cow), passage of feed through the rumen is slower and UIP may be reduced because time of exposure to microbial degradation is increased. Conversely, high intakes (e.g. peak lactation cow) reflect high rumen turnover rates, resulting in higher UIP values.
As parts of the CP fractions measured here, both forage ADF-CP and NDF-CP were influenced by varieties (Table 1). The ADF-CP was higher for Amisk, CDC Maverick, CDC Cowboy and CDC Bow than other varieties. CDC Austenson, Canmore, CDC Coalition, Altorado and CDC Bow seemed to have higher forage NDF-CP than other varieties. The ADF-CP is associated with the portion of the CP that is unavailable to the animal as a result of heat damage. NDF-CP is similar to ADF-CP, but NDF-CP has some digestibility associated with it. Usually, the NDF-CP is linked to by-pass protein. Meaning that as NDF-CP increases, the more by-pass protein you will have. In the present trial, Amisk significantly had more ADF-CP than most varieties, while Altorado had significantly more NDF-CP than most varieties.
Forage Energy
Looking at the total digestible nutrients (TDN) as a form of energy (Table 2), SR17519 significantly had higher TDN (72% TDN) than most varieties. Generally, varieties tested here had 67% TDN or more. Considering that mature beef cattle require 55% TDN and 60% TDN in mid pregnancy and late pregnancy respectively, and 65% during lactation (nursing beef cows), it is evident that all varieties tested here have exceeded the TDN requirements of mature beef cattle. Similarly, all varieties had enough TDN (65-70% TDN) required by growing and finishing calves.
Other forms of energy (Net energy lactation (NEL), net energy gain (NEG) and net energy maintenance (NEM)) were also significantly higher for SR17519 than other varieties (Table 2).
Forage Minerals
The forage macro and trace minerals are shown in Table 3.
Except for forage Na content, all macro minerals were significantly influenced by barley varieties tested. Forage Ca was highest for Amisk. Altorado had the highest forage P and S. Forage K was highest for SR17515.
The forage K, Mg, S and Na were adequate for mature beef cattle. Both forage Ca and P for the barley varieties tested within this trial were sufficient for a dry gestating beef cow. None of the barley varieties tested had adequate Ca for a lactating beef cow. Of the 16 barley varieties tested, only Altorado had adequate P for a lactating beef cow.
For trace minerals, none of the barley varieties had sufficient Cu for young and mature beef cattle. All barley varieties tested had sufficient Zn for young and mature beef cattle. Some barley varieties had sufficient Fe and Mn for young and mature beef cattle, but some varieties did not.
Overall, of the 16 barley varieties tested, only Altorado had sufficient macro (except for Ca) and trace (except for Cu) minerals measured for young and mature beef cattle. Because of the inability of most barley varieties to meet all the mineral requirements of young and mature beef cattle, it is essential to have free choice minerals (with guaranteed mineral analysis) when feeding any particular barley variety.
Conclusion
This year, as always, we included a few new barley varieties (e.g. AB Advantage and AB Cattlelac) in the evaluation of barley varieties for silage production. Overall, in our test this year, all barley varieties produced 4 tons of forage DM/acre or more. The top 5 varieties were Sundre, SR17515, Amisk, CDC Fraser and TR17639 with 5 tons DM yield/acre. In this year’s trial, most of the varieties tested produced higher forage DM yield than CDC Austenson (check). In most cases, the varieties had sufficient protein for mature beef cows. Surprisingly, with the amount of rainfall received later this year and the non-uniformity in plant growth earlier in the spring, the varieties tested had adequate energy (%TDN) for both young and mature beef cattle. All varieties fell short of meeting the Cu requirements of all categories of beef cow. Because of the inability of most barley varieties tested here to meet all the mineral requirements of young and mature beef cattle, it is essential to have free-choice minerals when feeding any particular barley variety.
Comentarios