Swath Grazing Research Articles

224 Yield and nutritive values of a polycrop and annual cereal monoculture used in winter swath grazing

Abstract This 3-yr study evaluated a comparative biomass yield and nutritive values of 2 forage systems: 1) a cereal monoculture (CDC-SO1 oats) and 2) a polycrops (PC) consisting of oat, brassicas (turnip and rape) and forage pea (4010) harvested at the hard dough (HD) stage for winter swath grazing purpose. A 12-ha field was divided into six, 2-ha paddocks, where each paddock was randomly assigned to 1 of 2 replicated (n = 3) forage systems. Forages were seeded in June and sampled for biomass yield and nutritive value at the soft dough (SD) and HD stages of oats. The seeding rate of oat monoculture (OM) was 157 kg/ha, while the PC was 45 kg/ha (oat), 11 kg/ha (forage pea) and 6 kg/ha (brassica). Forage samples were collected from a 0.6 m2 area at 24 pre-selected GPS points (4 per paddock), weighed and then oven-dried to a constant weight to determine DM yield. Data were analyzed using the PROC MIXED procedure of SAS and included treatment effects and treatments × stage interactions. Year was treated as a random effect due to climatic variations across years. For OM, there was a significant difference (P = 0.03) in biomass yield between SD (7,762.7 ± 1,217.9 kg/ha) and HD (8,902.8 ± 1,217.9 kg/ha) stages, while PC biomass yield did not differ (P = 0.94) between SD (5,922.4 ± 1,217.9 kg/ha) and HD (6,163.1±1,217.9 kg/ha) stages. The biomass yields between the two forage systems were different (P < 0.05) at the SD and HD stages. Crude protein (CP) concentration did not differ (P > 0.05) between the OM and PC at SD (10.4 vs 10.3%) and HD (8.9 vs 9.6%) stages. At the SD stage, significant differences (P < 0.05) between OM and the PC were observed for neutral detergent fiber (NDF, 50.9 vs 44.1%), calcium (0.2 vs 0.5%), phosphorus (0.2 vs 0.3%), and RFV-relative feed value (120.3 vs 142.2). Similarly, the starch (20.9 vs 16.5%), calcium (0.2 vs 0.5%), and phosphorus (0.2 vs 0.3%) values for OM and PC, respectively, also differed (P < 0.05) at the HD stage. Differences (P < 0.05) were observed between the SD and HD stages of OM for acid detergent fiber (ADF, 30.1 vs 27.0%), total digestible nutrient (TDN, 65.4 vs 67.9%), and starch (14.9 vs 20.9%) content, respectively. Study results suggest that swathing OM at the HD stage would be beneficial in terms of greater biomass yield without compromising quality, while PC can be harvested at either SD or HD stages based on the annual cereal component. Also, the lack of significant difference in the RFV, CP and TDN values between the PC and OM at the HD stage suggests that PC could be a viable alternative forage system for winter swath grazing.

Assessing supplementing strategies for beef cattle in a bale grazing system using grass hay during variable winter conditions

IntroductionBeef cattle in the Northern Great Plains of the United States of America are normally kept in open dry lot pens in winter. Practices such as bale grazing, swath grazing, stockpiling, and corn residue grazing, can be used to extend the grazing season and minimize dry lot use. Extending the grazing season has several advantages over dry lot use but arguably the most important benefit is cost savings due to lower labor and input costs. Strategies selected to supplement cattle in extended grazing systems should maintain cost savings while providing required nutrients to cattle. This study was conducted to evaluate supplementing strategies for beef cattle in a bale grazing system using grass hay during variable winter conditions. The study was conducted across variable winter conditions that are encountered in winters in the US Northern Great Plains.MethodsThe study extended over four years. Each year, non-lactating pregnant beef cows (n = 64, year 1; n = 80, year 2, 3, 4) were divided into eight groups of similar average body weight and randomly assigned to one of four bale grazing treatments as follows: a) bale grazing grass hay, b) bale grazing grass hay treated with a liquid supplement, c) bale grazing grass hay and alfalfa hay, and d) bale grazing grass hay and plus 1.8 kg corn DDGS/head/day. Animal performance was assessed from two-day body weights and body condition scores taken at the start and end of the study. Data analysis considered the fixed effects of treatment, year, and treatment x year interaction.ResultsFinal BW tended (P = 0.09) to be greatest following corn DDGS supplementation and lowest when grass hay was offered. The treatment strategy x year interaction (P = 0.026) for ADG showed that corn DDGS supplementation resulted in positive ADG across the years regardless of environmental conditions. Liquid or alfalfa hay supplementation resulted in positive ADG when environmental conditions were favorable. Final BCS (P = 0.005) and BCS change (P = 0.004) were greater following corn DDGS supplementation, intermediate following alfalfa hay or liquid supplementation and lowest when grass hay was fed. Supplementation costs ranged from $1.33 to $1.90/head/day, the highest cost occurred with corn DDGS supplementation mainly due to cost of corn DDGS and labor required to deliver corn DDGS to cattle on pasture.DiscussionAlfalfa hay or molasses-based liquids increased diet CP content but did not supply adequate energy in severely cold winters. Despite relatively higher supplement costs, high energy supplements such as corn DDGS may be required in severely cold winters where cattle require extra energy. Supplement selection should consider supplement effectiveness to meet animal nutrient requirements particularly in adverse winter conditions such as those encountered in the US Northern Great Plains.

187 Body Performance of Beef Steers Swathgrazing oat Monoculture or Forage-Blends During Winter Months

Abstract Extended grazing strategies have the potential to reduce beef winter-feeding costs. Beef producers can incorporate monoculture cereal crops in their winter swathgrazing programs, but recently, the use of polycrops (also known as intercrops or cover crops) is growing. There is little information about beef cattle body performance when swathgrazing forage blends during winter months. This study evaluated animal performance when swathgrazing oat monoculture or a polycrop blend (oat, turnip,canola and forage pea). Forage systems (treatment) were seeded on a 12-hectare site, further separated into 2-hectare paddocks. The paddocks were seeded in June and swathed in August at the hard dough stage for the oats. Forty-two crossbred steers were randomly allocated to one of two replicated (n=3) systems while balancing for body weight and breed composition. Body weights (BW) were determined over two consecutive days at the start and end of grazing, and at 2-wk intervals throughout the 86 d grazing period. Ultrasound backfat, rumpfat and intramuscular fat were collected at the start and end of the trial. At the start of the trial, two steers in each replicate group were fitted with rumen pH/temperature boluses. The biomass yield of the oat and polycrop were 6,225±651 and 4,867±471 kg DM ha-1, respectively, while mean regrowth for oat and polycrop were 177 and 1409 kg DM ha-1, respectively. Start-of-test BW (246, 247kg; P = 0.92), end-of-test BW (304, 303.5; P = 0.97), average daily gain (0.68, 0.74 kg d-1; P = 0.61), backfat change (0.53, 0.69 mm; P =0.65), rumpfat change (0.84,1.30 mm; P=0.14) and intramuscular fat change (-0.12, 0.14%; P=0.66) did not differ for steers assigned to oat and polycrop systems, respectively. Other measures were mean rumen temperatures (39.13oC, 38.96oC; P=0.03) and pH (6.76, 6.70; P=0.10) for the oat and polycrop respectively. These results suggest that polycrops may be an alternative in a swath grazing system during the winter months.

Swath Grazing Forage Sorghum and Pearl Millet Observations Regarding Quality and Utilization as Winter Feed

Swath grazing provides a viable winter feed option for beef cows in Iowa.

Strategies to Reduce Inorganic Fertilizer Inputs in Crop Production through Integrated Crop-livestock Systems

Adequate nutrition is essential for crop growth, production, and profit potential for farmers, but chemical fertilizer costs alone can constitute a greater portion of the total variable costs for wheat and canola. The present study evaluated seven cropping treatments (CT) in a 3-year crop rotation under two different soil types. Five of the CTs consisted of a one-time application (year 1) of beef cattle manure, and growing of cover crop cocktails (CCC) for annual pasture, swath grazing, green manure, and green feed. Canola and wheat were respectively grown in years 2 and 3 of the 3-year crop rotation. In year 2, CTs impacted canola seed yield and seed protein (only at site 2). Wheat had similar protein content in year 3 at both sites. At both sites, the application of beef cattle manure in year 1 seemed to encourage higher plant tissue P at the expense of plant tissue Zn. Overall, beef cattle manure and CCCs based CTs improved soil N, P, and K, but beef cattle manure application consistently improved crop yield and significantly reduced the need for additional in-organic fertilizer application to canola and wheat in subsequent years.

Breeding strategies in evaluation of forage barley

AbstractProducers on the Canadian Prairies grow barley (Hordeum vulgare L.) as a forage crop for ruminants, especially cattle. The purpose of our study was to determine methods to improve our selection of barley lines with superior forage value for ruminants. Data from the Western Cooperative Forage Barley Registration Test were used with permission of the Prairie Recommending Committee for Oat and Barley (PRCOB) and the breeders. Data were analyzed from 20 environments collected from 3 yr (2012–2014) and seven sites. We measured forage accumulation (FA) at the soft dough stage, five nutritive value traits, and three derived cow–calf variables. Although the variation in FA and forage nutritive value traits attributed to environment (E) was large, significant genotypic (G) effects were found for all traits measured. Whereas G× E effects were also significant, the mean square effect for G was up to 40 times higher than the mean squares for G×E. The proportion of variance attributed to G was greater for nutritive value traits than for FA. Significance of G means there was variability in the germplasm tested, and improvement through selection should be possible. The two parametric methods of stability analyses (Francis–Kannenberg method and Eberhart–Russell method) often identified the same lines as superior. Lines that were superior for FA and carrying capacity (cow on swath grazing, CC) were often different from those identified as superior for nutritive value, empty body weight gain (cow, EBWG) and average daily gain (backgrounding calf, ADG). A nonparametric method used to determine dynamic stability (Nassar–Hühn method) identified different lines as superior from the parametric methods. Breeders can use a combination of these selection criteria in breeding forage barley varieties with enhanced forage value for ruminants.

The evaluation of warm-season annual grasses as alternative sources of forage crops for beef cattle diets under northwestern Alberta conditions

ABSTRACT In recent years, there has been considerable interest in growing warm-season crops in monocultures and in mixtures for beef cattle production. The objective of this investigation was to measure the forage yield and nutritive value for the beef diet of 10 C4 and two C3 forage-type cereal crops. Forage yield was greater (P < 0.05) for C3 than C4 crops. The C4 crops generally had greater forage crude protein (CP) and total digestible nutrient (TDN) values comparable to C3 crops. Also, the C4 crops had higher Ca, P, K, Mg, Fe, and Zn than C3 crops. Both C3 and C4 crops were able to meet the requirements of CP, TDN, and minerals for a dry gestating beef cattle. Considering ease of establishment and forage yield, only four of the 10 C4 crops [two crown millet (Panicum miliaceum) varieties (red and white proso millets) and two sorghum Sudangrass (S. bicolor × S. Sudanese) varieties (BMR and Grazex III)] would be a fit for swath grazing or pasture.

Facilitating Crop–Livestock Reintegration in the Northern Great Plains

Integrated crop–livestock systems (ICLSs) can help increase food production while benefiting soils and the environment. This review summarizes recent impacts of ICLSs on crop and livestock production and rural economics and discusses lessons learned in the northern Great Plains (NGP). Research on ICLS conducted in the NGP indicates that the crop residue grazing, swath grazing, and annual forage grazing can positively influence crop production; whereas, livestock performance varies with season, forage nutritive value, and grazing management. Furthermore, ICLSs can reduce the costs and risks of agricultural production. The success of ICLSs in NGP region depends on trade‐offs, planning, economic benefits, policies, regulations, community acceptance, and management skills. The ICLSs could play a strategic role in future agricultural production. The lessons learned from adopting ICLSs in the NGP include the lack of available land for fertilizer (manure) management, that to implement ICLS practices skills and knowledge must be maintained, and ICLS provides an entry point for young farmers and ranchers however capital is needed. These experiences and lessons could be valuable references for producers to adopt ICLSs in the NGP or other regions.Core IdeasIntegrated crop–livestock systems positively affect crop production by improving soil health.Common integrated crop–livestock system management techniques can enhance the northern Great Plains crop production.Integrated crop–livestock system livestock performance is impacted by season, forage selection, and management.Integrated crop–livestock systems can increase economic benefits and reduce economic risks.Experiences and lessons in the northern Great Plains could be valuable for other regions to adopt integrated crop–livestock systems.

ANNUAL AND PERENNIAL FORAGES FOR FALL/WINTER GRAZING

Extending the grazing season by maintaining beef cattle on pasture in the fall/winter has been adopted by many producers on the Prairies as it reduces the need for mechanical harvesting and can lower labour and manure management costs relative to feeding cattle in confinement. Annual and perennial forages, alone or in combination, offer the potential for low-input grazing while maintaining animal productivity. Using a range of data sources, this paper will review the methods available for extending the grazing season of beef cattle using annual and perennial forages and discuss level of adoption and the practical implications and considerations for producers. These methods included stockpile grazing, bale grazing, swath grazing, and corn grazing, with the suitability of methods based on a range of factors including the nutritive requirements of the target class of cattle, environmental conditions, and costs of inputs. In an effort to maximise the efficiency of maintaining cattle on pasture in the fall/win...

Methane emissions from cattle grazing under diverse conditions: An examination of field configurations appropriate for line-averaging sensors

Micrometeorological techniques offer the possibility of a non-interfering measurement of enteric emissions from cattle in their natural environment, where animals do not need to be encumbered or handled. However, the grazing environment is a difficult application for these techniques. This study reports on an experimental design using an inverse dispersion method (IDM) to measure enteric methane (CH4) emissions, and its application to 15 rather distinct cattle trials in three types of feeding situations: summer grazing, winter swath grazing, and winter feeding. The IDM design was based on long and narrow animal paddocks with line-averaging sensors measuring CH4 concentration alongside the long axes of the paddock. Emissions were calculated based on the difference in concentration between the two measurement paths. The narrow paddock has many advantages for an IDM calculation: it avoids the need to monitor animal positions; it helps ensure measurable downwind concentration; and it increases the range of useable wind directions. Four different sensor configurations were used in the trials, differing in the number of concentration sensors (one or two) and sensor paths (two or four). Some configurations used sensor aiming motors to give multiple measurement paths and others used mirrors to create segmented paths (i.e., to go around a paddock corner). Cattle emissions measured with the IDM design showed good agreement across the 15 trials, consistent with high forage diets. When expressed in terms of CH4 yield (g/kg dry matter intake), the three feeding situations averaged 21.3 (summer grazing), 23.4 (winter grazing), and 23.9 (winter feeding). Based on the trial-to-trial consistency of the results, the similarity with other literature studies, and the success of a previous tracer-release study, we conclude that the narrow paddock IDM design provides a flexible and accurate method for calculating CH4 emissions from grazing cattle.

Assessment of grazing management on farm greenhouse gas intensity of beef production systems in the Canadian Prairies using life cycle assessment

Grazing is a common practice in the beef cattle industry and is an integral component of pasture and rangeland management. The objective of this study was to evaluate impacts of grazing management scenarios on greenhouse gas (GHG) intensity [kg carbon dioxide equivalents (CO2e)kg−1 beef] at the farm-gate for beef production systems in western Canada using life cycle assessment. A life cycle assessment over an 8-year period was conducted on a hypothetical but typical beef farm that managed 120 cows, 4 bulls, and their progeny. Calves were backgrounded (raised) on rangeland and market cattle were finished on grain for an average of 134±11d. Four grazing management scenarios were examined: i) light continuous grazing (LC) for all cattle, ii) heavy continuous grazing (HC) for all cattle, iii) light continuous grazing for cow-calf pairs and moderate rotational grazing for backgrounded cattle (LCMR), and iv) heavy continuous grazing for cow-calf pairs and moderate rotational grazing for backgrounded cattle (HCMR). Greenhouse gas emissions from various sources within the farm were estimated using the whole-farm model, Holos. Soil organic carbon (C) change due to each grazing management scenario was estimated using the Introductory Carbon Balance Model. Primary model inputs came from short- and long-term grazing management studies. Greenhouse gas intensity of beef varied among grazing management scenarios, ranging from 14.5–16.0kgCO2ekg−1 live weight and 24.1–26.6kgCO2ekg−1 carcass weight. Greenhouse gas intensity decreased with increasing stocking rate: that of HC grazing management was 9.2% lower than that of LC treatment (14.5 vs 16.0kgCO2ekg−1 live weight, respectively). Greenhouse gas intensity was similar (<3%) between LC and LCMR or between HC and HCMR, indicating that the use of moderate rotational grazing for the backgrounding operation in LCMR and HCMR had no effect on overall intensity estimates. However, LCMR management had 7% higher GHG intensity than HCMR (15.6 vs 14.6kgCO2ekg−1 live weight, respectively). Average farm production efficiency (kg beef per unit land area) was 17–25% higher for the HC and HCMR grazing management scenarios than the LC and LCMR scenarios. Regardless of grazing management, methane emission from enteric fermentation was the major source of emissions (67–68% of total), followed by nitrous oxide (14–16% of total) from manure management. The rate of soil C sequestration ranged from 0.01MgCha−1yr−1 for rangeland under HC to 0.46MgCha−1yr−1 for a triticale field used for swath grazing. When soil C sequestration was included in the total emission analysis, GHG intensity estimates decreased by 12–25%, and there was no difference in intensity estimates among the scenarios. The largest reduction in GHG intensity arising from soil C sequestration was observed for LC (22%) and LCMR (25%) because they sequestered more C than HC and HCMR. Overall, results of our study indicated that grazing management impacted GHG intensity of beef production by influencing diet quality, animal performance and soil C change. It also emphasizes the importance of accounting for all emission sources and sinks within a beef production system when estimating its environmental impacts.

248 Validating the stage of maturity at harvest for barley, oat, and triticale for swath grazing

248 Validating the stage of maturity at harvest for barley, oat, and triticale for swath grazing

Effect of winter feeding systems on farm greenhouse gas emissions

Overwintering beef cows is a major cost in Canadian cow-calf production systems and swath grazing is a potential alternative to reduce winter feeding cost relative to the traditional drylot feeding systems. The objective was to estimate and compare greenhouse gas (GHG) emissions from winter feeding systems: i) swath grazing on triticale, ii) swath grazing on corn, and iii) conventional drylot feeding systems (control). Data were obtained from a study conducted over three production cycles (2008/2009, 2009/2010, 2010/2011) at the Lacombe Research Center in western Canada. Greenhouse gas emissions were estimated by calculating methane (CH4), nitrous oxide (N2O) and carbon dioxide (CO2) emissions from different sources using Intergovernmental Panel on Climate Change (IPCC) Tier 2 approach. Methane emissions were estimated from enteric fermentation and manure, N2O emissions from fertilization and manure, and CO2 emissions from energy use for farm activities related to feed production and processing, feed and bedding delivery and manure removal. Total emission expressed per kg of feed produced and fed were significantly (P<0.001) lower for both the swath grazing treatments relative to the control treatment. Emissions per cow varied among treatments (P<0.001), higher for control (12.3kg CO2e cow-d−1) than corn (9.4kg CO2e cow-d−1), with triticale (11.0kg CO2e cow-d−1) intermediate. In all the treatments, the largest fraction of emissions was enteric CH4 (69–76%), followed by N2O (14–24%). The contribution of energy-derived CO2 emissions for total GHG emissions was lower in swath grazing treatments (5–7%) compared to a traditional feeding system (11%) due to their minimal energy use. Farm activity related energy use was 9.4, 11.5 and 21.4MJ cow-d−1 for triticale, corn and conventional drylot feeding, respectively. This study indicated that swath grazing on triticale or corn can be an effective alternative winter feeding systems to reduce GHG emissions and increase energy use efficiency of Canadian beef cattle industry.

Swath grazing oat or grazing stockpiled grass compared to a traditional winter feeding method for beef cows in central Alberta

Swath-grazed oat (Avena sativa L.) and stockpiled meadow bromegrass (Bromus riparius Rhem) were compared with (Control) a pen-fed straw-based total mixed ration (TMR) for dry, pregnant beef cows (670 ± 88 kg BW) using carrying capacity, nutritive value, cow performance, daily feeding, yardage, and total daily costs. Carrying capacity ranked (P Control (454 cow-d ha−1) > stockpiled grass (189 cow-d ha−1). In vitro true digestibility (IVTD) ranked (P oat (588 g kg−1) > Control (530 g kg−1). Average cow body condition score (BCS) off pasture was (P oat (3.0), while the control was intermediate (3.3). The daily feed cost ranked: stockpiled grass ($0.38 cow-d−1) < swathed oat ($0.48 cow-d−1) < Control ($1.05 cow-d−1). Yardage (non-feed costs) ranked: oat ($0.41 cow-d−1) < stockpiled ($0.50 cow-d−1) < Control ($0.91 cow-d−1). Total daily cost was similar for oat ($1.07 cow-d−1) and stockpiled grass ($1.04...

Forage Intake and Wastage by Ewes in Pea/Hay Barley Swath Grazing and Bale Feeding Systems

Forage Intake and Wastage by Ewes in Pea/Hay Barley Swath Grazing and Bale Feeding Systems

Estimating swath-grazed carrying capacity from plot-scale data

Doce, R. R., Baron, V. S., and Dick, A. C. 2015. Estimating swath-grazed carrying capacity from plot-scale data. Can. J. Plant Sci. 95: 647–651. A spreadsheet calculator was developed to estimate farm-scale carrying capacities for swath grazing beef cows with forage yield and quality data from small areas within fields or paddocks. It could be used to compare agronomic treatments for swath grazing potential from plot data when combined with existing beef nutrition equations. Examples using either in vitro true digestibility at 30-h digestion or acid detergent fiber (ADF) in equations to estimate digestible energy were compared with actual field-scale carrying capacities to evaluate the ability of the methods to meet requirements of scale, precision and accuracy. Both methods were capable of estimating carrying capacity at a realistic whole-farm scale, but the ADF-based method was superior with respect to accuracy and precision characteristics.

Individual mineral supplement intake by ewes swath grazing or confinement fed pea-barley forage

Previous research has reported high variation in intake of self-fed protein and/or energy supplements by individual animals, however little is known about variation in consumption of mineral supplements. Sixty mature range ewes (non-pregnant, non-lactating) were used in a completely randomized design repeated 2 years to determine if feeding method of intercropped field pea (Pisum sativum L.) and spring barley (Hordeum vulgare L.) forage (swath grazed or fed as hay in confinement) affected individual ewe mineral consumption. Thirty ewes were allocated to 3 confinement pens (10 ewes/pen) and 30 ewes were allocated to 3 grazing plots (10 ewes/plot). Ewes had ad libitum access to feed, water, and a mineral supplement containing 1% titanium dioxide as an external marker. Forage dry matter intake (DMI) was calculated using estimates of fecal output, and in vitro 48-h forage DM digestibility. Ewe supplement intake was determined from fecal and supplement Ti concentrations, and fecal output. Forage and mineral intakes were analyzed using ewe as the experimental unit, and plot or pen as the experimental unit for intake variation. A year×treatment interaction (P<0.01) existed for DM forage and mineral intake. Ewes in confinement consumed more forage DM than grazing ewes in 2010, but less than grazing ewes in 2011. Mean mineral intake was highest (P<0.01) by grazing ewes in 2011 and 2010 (average 69g/day), intermediate by confinement ewes in 2010 (57g/day), and lowest by confinement ewes in 2011 (31g/day). A year×treatment interaction (P=0.05) existed for mineral intake CV which was higher (P=0.04) for confinement ewes in 2011 (67 vs. 34%), but was not different (P>0.05) between treatments in 2010. In this study, variation in individual ewe intake of mineral supplement was large in both grazing ewes and ewes fed hay in confinement.

Economic analysis and stochastic simulation of alternative beef calving and feeding systems in western Canada

Khakbazan, M., Carew, R., Scott, S. L., Chiang, P., Block, H. C., Robins, C., Durunna, O. N. and Huang, J. 2014. Economic analysis and stochastic simulation of alternative beef calving and feeding systems in western Canada. Can. J. Anim. Sci. 94: 299–311. Biological and economic data from three field-experimental sites in Manitoba (Brandon Research Centre) and Saskatchewan (Western Beef Development Centre; Semi-Arid Prairie Agriculture Research Centre) were used to determine the economic and financial benefits of alternative beef calving and feeding systems. Stochastic budgets and Monte Carlo simulation techniques were used to evaluate the profitability and risk levels of four alternative livestock beef management systems: early-calving/rapid-gain post-weaning feeding (ER), late-calving/rapid-gain post-weaning feeding (LR), early-calving/slow-gain post-weaning feeding (ES), and late-calving/slow-gain post-weaning feeding (LS). Economic budgets were constructed to evaluate the viability of different phases of beef production including backgrounding, pasture, swath grazing and finishing. Statistical analysis considered operational costs (feed, yardage, implants, medicine, labor, marketing, and other costs), price variables (fed-steer, feeder cattle, and grid pricing premiums/discounts) and steer performance measures such as average daily gain (ADG). Results from the simulation analysis revealed that late-calving systems provided higher returns for livestock producers, while rapid-feeding systems were more preferable for producers who were more risk-averse.

The effect of cultivar and fungicide application on the yield and quality of late-seeded forage oats used for swath grazing

<h2>ABSTRACT</h2> The productivity and disease tolerance of annual forages may have large effects on the performance of beef cattle in a swath-grazing system. This study was conducted to evaluate the effects of crown rust (Puccinia coronata Corda f. sp. avenae Eriks.) on the forage yield performance of 2 oat (Avena sativa L.) cultivars (HiFi and CDC Baler) with or without fungicide application in a swathgrazing system. The cultivar HiFi has good resistance to crown rust, whereas CDC Baler is susceptible to crown rust. Unfortunately, barley yellow dwarf virus (BYDV) infected both cultivars and may have influenced the results of the current study. Forage DM yield, regrowth, and forage residue yield samples were collected from each treatment. The nutritional quality of the samples was also analyzed. Mixed-model ANOVA was used in the statistical analysis of forage yield and nutritional performance. The cultivar effect was significant (P<0.01) for DM yield, regrowth, residue yield, and nutrient quality. The application of fungicide had no influence (P>0.61) on the DM yield, regrowth, and residue yield of the cultivars. There was no interaction effect (P>0.16) between cultivar and fungicide application for all yield performances. The results from this study suggest that using a resistant cultivar (HiFi) resulted in greater (P<0.01) forage DM yield and gross margins. The application of fungicide on HiFi was not economical because of the cultivar's resistance to crown rust. The HiFi cultivar also showed moderate resistance to BYDV. Although agronomic traits need to be considered in selecting cultivars for swath grazing, it is also important for producers to select cultivars with good disease packages that are environmentally suited to the production area. Because of its susceptibility to BYDV, CDC Baler may not be suitable for swath grazing in areas with severe BYDV infestation.

Swath grazing triticale and corn compared to barley and a traditional winter feeding method in central Alberta

Baron, V. S., Doce, R. R., Basarab, J. and Dick, C. 2014. Swath-grazing triticale and corn compared to barley and a traditional winter feeding method in central Alberta. Can. J. Plant Sci. 94: 1125–1137. A 5-yr study compared swath-grazed triticale (× Triticosecale Wittmack), corn (Zea mays L.) and barley (Hordeum vulgare L.) with a traditional pen-fed, wintering diet for gestating beef cows on the basis of dry matter (DM) yield, carrying capacity, nutritive value, cow performance and total daily feeding cost. Cows (690±70 kg BW) were fed a control total mixed ration (TMR) or allocated to swath-grazed treatments in 2.5-ha paddocks. Triticale yielded 15% more than corn and corn 32% more than barley. Carrying capacity of triticale (1145 cow-d ha−1) and corn (1004 cow-d ha−1) were similar and both were greater (P&lt;0.05) than control (516 cow-d ha−1) and barley (554 cow-d ha−1). Average utilization for triticale (83.7%) was greater (P&lt;0.05) than corn (74.7%) and barley (71.7%). In vitro true digestibility (IVTD) for corn was highest (682 g kg−1), followed by triticale (620 g kg−1), then barley (570 g kg−1) and the control TMR (571 g kg−1). Average cow mean body condition score (BCS) was higher (P&lt;0.05) for triticale and corn (3.0) than barley (2.9), but lower than the control (3.1). Thus, cow reproductive performance should not be compromised by swath grazing. Total daily feeding costs, averaged over years, ranked (P&lt;0.05) triticale ($0.78 cow-d−1)&lt;corn ($1.05 cow-d−1)&lt;barley ($1.24 cow-d−1)&lt;control ($1.98 cow-d−1).