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Cover crop (CC) grazing can be a strategy to reintegrate livestock with crops, but how this integration affects soils and crop yields is unclear. We studied the impact of cattle grazing an oat (Avena sativa L.) CC in the fall on soil properties of a silt loam in a field‐scale irrigated no‐till corn (Zea mays L.)–soybean [Glycine max (L.) Merr.] experiment in eastern Nebraska. Each rotation was present each year in two adjacent fields. During the 5‐yr study, Field I was grazed two times, and Field II was grazed three times. Grazing occurred on each field every other year. Treatments were arranged in a split‐plot design with corn harvest (corn silage and high‐moisture corn [HMC]) as main plots with no CC, nongrazed CC, and grazed CC as split plots. Corn silage was harvested 15 d before HMC; HMC was harvested about 25 d before typical corn harvest time. Cover crop grazing reduced aboveground CC biomass without affecting soil penetration resistance, bulk density, aggregate stability, hydraulic properties, organic matter concentration, particulate organic matter concentration, microbial biomass, and corn and soybean yields compared with nongrazed CC. Likewise, compared with no CC, nongrazed CC had no effect except for some improvement in soil microbial properties. However, corn silage harvest negatively affected most near‐surface soil properties but not crop yields compared with HMC. Cover crop did not generally offset the negative impacts of corn silage on soil properties. In conclusion, CC grazing had no impact on soil properties and yields, but corn silage adversely affected soil properties. Core Ideas: Grazed and nongrazed cover crop did not generally affect soils or crop yields.Corn silage negatively affected soils but not yields compared with high‐moisture corn.Cover crops did not interact with corn silage and high‐moisture corn harvest.Cover crop did not offset the adverse effects of corn silage on most soil properties.Cover crop grazing can be a potential management to support livestock production. [ABSTRACT FROM AUTHOR]

Annual forages provide a valuable grazing resource for cattle producers; however, annuals are prone to accumulating nitrate and have the potential to cause nitrate toxicity. Although these forages pose a risk of containing high nitrate concentrations, they can be a high-quality feed source. Understanding the factors that affect the potential for toxicity when using these forages is important to help nutritionists and producers make management decisions. This review describes the previous research, current guidelines for nitrate toxicity, and the potential for improvement in our current recommendations. Current extension toxicity guidelines appear to be founded primarily on drenching based studies and overestimate the nitrate toxicity potential of forages. Recommendations need to account for multiple factors that affect the threshold for toxicity. There is evidence that fresh forages have a lower risk of toxicity because of slower release of nitrate into the rumen and a slower rate of dry matter intake. Increased dietary energy and sulfur content reduce the potential for toxicity. Microbial adaptation can reduce the risk and allow use of potentially toxic forages. These factors should influence feeding recommendations. However, there is currently not enough data available to establish new guidelines that account for these main factors. Thus, there is a need for renewed research in this area. The limited number of studies grazing elevated nitrate forages seems to suggest that there is less risk in grazing situations, especially if animals graze selectively. There is a need to develop guidelines for nitrate toxicity and management recommendations when grazing. To accomplish this, there is a need for more studies to evaluate risk of toxicity in grazing situations. These grazing studies need to evaluate the effects of nitrate concentration, forage quality, and grazing management on the potential for nitrate toxicity. While the conservative guidelines that are currently in use reduce risk of nitrate toxicity, they may also cause a significant increase in feed costs for producers. [ABSTRACT FROM AUTHOR]

A 2-year study conducted at the Eastern Nebraska Research and Extension Center near Mead, Nebraska determined the effects of backgrounding rate of gain and implanting during the winter or summer phases on animal performance and carcass traits. The study design was a 2 x 3 factorial arrangement with the factors of winter gain (0.45 or 0.90 kg/d; LG and HG, respectively) and three implant strategies. The implant strategies included a 36 mg zeranol (Ralgro; Merck Animal Health, De Soto, KS) implant during the winter phase and 40 mg trenbolone acetate and 8 mg estradiol (Revalor-G; Merck Animal Health) implant during the summer phase (STRNG), no implant during the winter phase and Rev-G during the summer phase (MED), and no implant during the winter or summer phases (NONE). The study used 240 (initial BW = 247 kg, SD = 5.9 kg YR 1; BW = 255 kg, SD = 10.9 kg YR 2) weaned steers each year that were fed one of two backgrounding diets consisting of bromegrass hay and 10% MDGS (LG) or 30% MDGS (HG). Steers were backgrounded in the feedlot for a 148-day winter phase followed by a 56-day summer phase where they grazed smooth bromegrass paddocks. Upon arrival in the feedlot for the finishing phase, steers received 200 mg TBA and 40 mg estradiol (Revalor-XS; Merck Animal Health) and were fed a common diet for the entire finishing phase. In the winter phase, steers fed the HG diet had a greater ADG, ending BW, DMI, and improved G:F over steers fed LG (P < 0.01). Steers that received a Ralgro implant during the winter phase (STRNG) were observed to have an 13% improved ADG (P < 0.01), a 10% increase in G:F (P < 0.01), and an additional 14 kg of BW for the winter phase. There were no interactions between the rate of gain and implant strategy (P = 0.15) during the winter period. In the summer, HG steers had maintained greater ending BW than LG, although LG steers had greater ADG than HG (0.70 and 0.53 kg, respectively; P < 0.01) due to compensatory gain. Steers assigned to HG during the winter phase had a greater IBW for the finishing phase. Steers fed HG during the winter and administered an implant at both backgrounding phases (STRNG) had the greatest HCW with no differences in ADG or G:F during the finishing phase. Combining a strong implant program and an increased rate of gain during winter backgrounding resulted in 34 kg of additional HCW at marketing. Implant strategy and rate of gain during the winter growing period had additive effects to increase animal performance through all phases. [ABSTRACT FROM AUTHOR]

Soybean harvest leaves little residue, potentially subjecting the soil to negative environmental impacts. Additionally, integrated livestock producers with crops and cattle identified a need to fill early spring forage deficiencies. Planting winter-hardy cereal cover crops after soybean harvest provides ground cover until the next cash crop is planted and has potential for early spring grazing before perennial pastures are ready. A 3-year study was conducted near Mead, Nebraska to evaluate the grazing potential of winter wheat, winter triticale, and cereal rye when planted after soybean harvest. A 7.3-ha field was split into nine 0.81-h paddocks and paddocks were then randomly assigned to a small cereal species (n = 3 paddocks per treatment), then divided further into 2, 0.4 ha paddocks to allow for rotational grazing within the assigned paddock. Growing steers were stratified by body weight (BW) and randomly assigned to paddock with 6 steers per paddock in years 1 and 2, and 5 steers per paddock in year 3. Steers were limit-fed at 2% of BW to equalize gut fill and weighed before and at the conclusion of grazing. Grazing was initiated when a paddock reached 13 cm. The initial BW did not differ among treatments (P > 0.05) with steers weighing 303, 335, and 372 kg in years 1 through 3, respectively. The final BW did not differ among treatments (P > 0.05). There was a treatment by year interaction (P = 0.01) for average daily gain (ADG). There were no differences (P > 0.05) in ADG among treatments in year 1 (1.9 kg/d) or year 3 (1.3 kg/d). However, in year 2, steers grazing rye gained more (P < 0.01) at 1.4 kg than wheat (0.83 kg) and triticale (0.67 kg), which did not differ (P > 0.05). There were no differences (P > 0.05) among treatments for animal unit months (AUM) per hectare. Year 1 provided the most (P < 0.01) grazing at 5.1 AUM/ha, year 2 provided the least (P < 0.01) at 2.4 AUM/ha, and year 3 was intermediate at 3.1 AUM/ha. For gain per hectare (GPH), there were no differences (P > 0.05) among treatments. Steers in year 1 had greater (P < 0.01) GPH (390 kg/ha) than subsequent years, with year 2 (93 kg/ha) being less (P < 0.01) than year 3 (151 kg/ha). For all 3 years, there were no differences among treatments in pre-graze (P > 0.05) or postgraze biomass (P > 0.05). These data suggest that during early spring there are no major differences in the grazing potential and growing cattle performance for wheat, rye, or triticale in eastern Nebraska. [ABSTRACT FROM AUTHOR]

Supplemental feed may be provided to cattle in grazing systems to increase ADG, but can be labor intensive. This study evaluated the performance of steers grazing smooth bromegrass pastures supplemented dried distillers grains plus solubles (DDGS) either daily or three times per week. Crossbred steers (n = 144, initial BW 317 ± 1.25 kg) were used in a randomized complete block design with 3 treatments allocated randomly to 24 paddocks in one of 6 blocks. Treatments consisted of: 1) steers supplemented daily with 0.8% of BW (DM-basis) of DDGS, 2) steers supplemented three times a week with 1.86% of BW (DM-basis) of DDGS, and 3) steers that received no supplementation (control). All steers were implanted with 40 mg trenbolone acetate and 8 mg estradiol (Rev-G; Merck Animal Health, De Soto, KS) implants. Paddocks were divided equally into three strips and rotationally grazed. Put-and-take steers were utilized to match stocking rate with forage growth. Each treatment group rotated through three 0.81-hectare strips per pasture. Pre-graze and post-graze biomass was measured at ground level from each paddock at each rotation. Pre-graze biomass samples were used to determine forage availability. Grazing was initiated in early May with cattle removed from pastures in August, for a total of 97 grazing days. Data were analyzed with MIXED procedure of SAS with paddock as experimental unit and treatment and block as fixed effects. Treatment means of ADG and ending BW differed (P < 0.01) among treatments. The control calves gained 0.85 kg/d. The supplemented treatments significantly increased (P < 0.01) ADG compared with the control, with daily supplementation gaining 1.25 kg/d and 3x gaining 1.11 kg/d. The ADG was decreased (P < 0.01) with 3x a week compared with daily supplementation. The differences in ADG resulted in similar differences in final live BW. The control had a finial live BW of 398 kg and final live BW of both supplemented treatments was significantly increased (P < 0.01) when compared with the control treatment. Final live BW of 3x supplemented steers (423 kg) was decreased (P < 0.01) when compared with daily supplemented steers (436 kg). For steers grazing smooth bromegrass pastures, daily supplementation of DDGS resulted in greater gains and therefore greater final BW when compared with three times a week supplementation and the non-supplemented control. [ABSTRACT FROM AUTHOR]

Cows fed diets consisting primarily of stored forages and concentrates may be at risk for vitamin A deficiency because these feedstuffs are low in ß-carotene. Furthermore, dietary vitamin A concentrations of the cow during late gestation will affect vitamin A concentrations in colostrum, which calves rely on at birth to supply vitamin A. The objective of this study was to evaluate how level of vitamin A supplementation from mid-gestation to early lactation affected cow and subsequently, liver retinol concentrations of their calf. Multiparous beef cows (n = 54) were stratified by body condition score and previous source and assigned to pen (n = 9); 3 pens were assigned to each of the following treatments: current NASEM recommendation (31,000 IU/d; 1X), 3 times (93,000 IU/d; 3X), or 5 times (155,000 IU/d; 5X) the current NASEM recommendation for supplemental vitamin A. Cows were limit-fed a diet consisting of wheat straw, corn silage, and wet distillers grains. Liver biopsies were collected on cows 3 weeks before treatment initiation, d 40 and d 81 of supplementation, and both cows and calves were sampled 32 days post-calving (165 ± 22 d SD of supplementation). No differences (P=0.86) in initial cow liver retinol (mean 186 μg/g DM) were observed between treatments. A significant treatment × day interaction (P < 0.01) was observed for cow liver retinol. On d 40, cows in 1X had liver retinol concentrations (178 μg/g DM) that were not different (P = 0.12) from 3X (213 μg/g DM) but less (P = 0.02) than 5X (241 μg/g DM), while 3X and 5X did not differ (P = 0.21). Liver retinol on d 81 was less (P < 0.05) in 1X (189 μg/g DM) compared with 3X (334 μg/g DM) and 5X (412 μg/g DM), which did not differ (P = 0.20). For cow liver retinol post-calving, 1X (187 μg/g DM) was less (P< 0.05) than 3X and 5X, and 3X (454 μg/g DM) was less (P< 0.05) than 5X (674 μg/g DM). Liver retinol concentrations of 1X cows remained below adequate reference ranges (300-700 μg/g of DM) throughout the study, whereas 3X and 5X were increased into the adequate range by d 81. Calf liver retinol concentration also differed among treatments (P = 0.01), as calves of cows in 1X had less (P < 0.05) liver concentrations than 3X and 5X calves which did not differ (P=0.12). Liver retinol concentrations considered adequate for calves at 32 days of age (100-350 μg/g of DM) were not observed in 1X calves (51 μg/g DM) but were observed in calves from 3X and 5X cows (119 and 165 μg/g DM, respectively). Supplementing cows with 93,000 IU/d of vitamin A for 165 days brought liver retinol concentrations of cows and their calves up within adequate reference ranges. [ABSTRACT FROM AUTHOR]

The cattle industry and its associated markets are inherently volatile, leading producers to search for more economically sustainable production practices. Supplementation with high protein feed increases yearling gain. However, strategically supplementing in the latter half of the grazing season, as forage quality declines, could provide a more economical increase in gain and return to management. Therefore, a threeyear experiment was conducted at the High Plains Agriculture Laboratory, in Sidney, NE. The effects of strategically supplementing dry distillers grains (DDG) on yearling cattle performance and return to management were compared among a variety of economic conditions. Yearlings (313±46 kg) were stocked at 4.3 ha/animal on crested wheatgrass pastures for an average of 112 days beginning in mid-May. They were supplemented either throughout the entire period (FULL), only during the latter part (STRAT), or not at all (CONT) (n = 4 reps/treatment in years 1 and 2, 3 reps/treatment in year 3). Supplemented yearlings received 1.59 kg of DDGs 6 days/week. On average, CP (%DM) of crested wheatgrass declined from 10.2 (May) to 6.8 (September), while IVDMD (%DM) declined from 51 (May) to 37 (September). There were no significant (P > 0.53) experimental year and treatment effects for cattle performance. However, there was an effect (P < 0.01) of treatment and year on ADG and final body weight. On average, non-supplemented yearlings had an average daily gain (ADG) of 0.68 kg/d. Providing supplement increased ADG by 0.23 kg/d (P < 0.01). Performance did not differ (P < 0.01) between STRAT and FULL, despite STRAT receiving nearly half (54%) the amount of supplement. Cattle and DDG prices from the previous decade (2012–2021) were applied to experimental data to create various potential marketing scenarios. Return to management was calculated as the return to labor costs for providing supplement. On average, FULL returned $14.96 more and STRAT returned $32.21 more per yearling than CONT. Within economic year, return of STRAT was greater (P ≤ 0.05) than CONT in all years except 2012, 2019 and 2021. Return of FULL was greater (P ≤ 0.05) than CONT in all years except 2012, 2018, 2019, and 2021. Numerically, STRAT was always greater than CONT and FULL. Higher DDG prices coupled with lower live cattle prices caused less return in those years. Breakeven DDG costs for STRAT averaged $530/909 kg and ranged from $268/909 kg to $822/909 kg. Applying a $0.30/yearling/day labor cost, the average breakeven for this strategy declines to $345/909 kg of DDG. These results suggest that strategically supplementing DDG as forage quality of crested wheatgrass declines in the summer will provide similar yearling performance to supplementing throughout the entire grazing season. Strategic supplementation also appears to have a high likelihood increasing return to management. [ABSTRACT FROM AUTHOR]

Winter-hardy small grains offer an opportunity to improve soil health as a cover crop, and they can also be used as a forage source for cattle. Winterhardy small grains differ in the time needed to reach various maturity stages. Species selection may also impact yield and nutritive value. A two-year study was conducted in eastern Nebraska to determine the effect of species and maturity on yield and nutritive value of winter-hardy small grains used for silage. Three species were evaluated; cereal rye, winter wheat, and winter triticale at four stages of maturity: boot, anthesis, milk, and soft dough. The experimental design was a randomized complete block design with four blocks per year. Small grain species were considered whole plots with maturity at harvest considered sub-plot. Each year, the small grain species were randomly assigned within each block. Within each plot, maturity was randomly assigned to one quarter of each plot. Dry matter (DM) forage yield, crude protein (CP), digestible organic matter (DOM), and nutrient yield per hectare were measured and analyzed using the mixed procedure of SAS. Forage yield increased for all species (P < 0.01) with maturity, except for wheat, where there was a decrease at soft dough. Forage yield of cereal rye and triticale did not differ (P>0.05), except at soft dough where triticale was greater (P < 0.01) than cereal rye. Forage yield of triticale and cereal rye yield was greater (P£0.05) than wheat at anthesis and soft dough. Crude protein (% DM) decreased (P < 0.01) with maturity across all species. Among species, CP for cereal rye was greater (P£0.01) than triticale at boot, anthesis, and soft dough, but not different (P³0.10) from wheat at boot, milk, and soft dough. At boot, anthesis, and milk stages, CP of triticale was not different (P³0.07) than wheat, but triticale was lower than wheat (P < 0.01) at soft dough. The DOM (% DM) decreased (P < 0.01) with maturity, except at soft dough. The DOM of cereal rye and wheat did not differ (P > 0.05), but both were greater (P < 0.01) than triticale. Cereal rye and triticale had greater (P £ 0.05) nutrient yields than wheat in terms of energy (DOM) and CP. There was no difference for CP yield across stages (P = 0.10), but there was an effect of maturity on DOM yield. The DOM yield increased from boot to anthesis, (P = 0.05), anthesis and milk did not differ (P = 0.08) and increased (P < 0.01) again at soft dough. This suggests that planting either cereal rye or triticale resulted in the greatest nutrient yield per acre. Harvest at anthesis had increased yield compared to boot with minimal loss in nutritive value; for maximizing energy yield per acre, harvesting at soft dough was the best option. [ABSTRACT FROM AUTHOR]

In the young calf, vitamin A is particularly important for immune system maturation, and calves rely on colostrum at birth to supply vitamin A. Cow vitamin A status may influence colostral vitamin A concentrations, which can impact vitamin A status of their calves. Very little is understood about this relationship between beef cow and calf vitamin A status. Furthermore, limited data is available on how plasma and liver retinol concentrations in cattle are related to one another. The objective of this study was to examine relationships between liver and plasma retinol concentrations in the cow, calf, and within cowcalf pairs. Multiparous MARC II beef cows (n = 120; 6.4 ± 1.2 SD years of age; 592 ± 58 SD kg BW) in mid-gestation were provided supplemental vitamin A as retinyl acetate in a supplemental pellet at a rate of 21,125 ± 8,560 SD IU/d (current NASEM recommendation = 33,000 IU/d). Cows were individually fed using Calan gates a diet consisting of alfalfa hay, corn silage, and supplemental pellet for 144 d (111 d pre-calving and 32 d post-calving). Basal diet vitamin A concentration was 490 IU/kg of DM. Mean initial liver concentration of cows was 830 μg retinol/g of DM. To assess vitamin A status, liver biopsies and plasma samples were collected on cows and calves at the end of the supplemental period when calves averaged 32 ± 7 days of age (DOA). Pearson correlations were used to test for linear relationships between cow liver and plasma retinol concentrations, calf liver and plasma retinol concentrations, and liver and plasma retinol concentrations between the cow and her calf. No linear relationship (P = 0.10; r=0.16) was observed between liver and plasma retinol in cows. In the present study, mean cow liver retinol concentration (482 ± 182 SD μg/g of DM) fell within the current adequacy reference range of 300–700 μg/g of DM. Cow plasma retinol (272 ± 40 SD ng/mL) was slightly below the reference range of 300–800 ng/mL. A positive correlation (P < 0.01; r=0.37) was detected between calf liver (51 ± 27 SD μg/g of DM) and plasma (190 ± 47 ng/mL) retinol concentrations. Both were below what would be considered adequate (100–350 μg/g of DM in liver; 225–325 ng/mL in plasma) for calves at 32 DOA. There was a positive correlation (P < 0.01; r=0.31) between cow and calf liver retinol, suggesting that as cow retinol liver concentrations increased, calf liver retinol concentrations increased. It appears that despite cows having adequate liver retinol concentrations when 21,125 IU vitamin A/d was fed, it did not result in calf liver retinol stores that would be considered adequate given current reference ranges. USDA is an equal opportunity employer and provider. [ABSTRACT FROM AUTHOR]

Conversion of perennial grasslands to crop land in U.S. Northern Plains has resulted in a need to evaluate alternative management strategies for cow-calf production. A 3-yr study was conducted to compare beef cow/calf performance in two different August-calving cow systems. Multiparous beef cows (n = 318) were allocated to 8 replicates, and replicate was randomly assigned to drylot (DL) or pasture (PAST) treatments. From mid-gestation (March/April) until breeding (October), DL cows were limit-fed to meet requirements and PAST cow grazed perennial pasture. Feed resource during the 47-d breeding period (November/December) varied by year and treatment. However, pregnancy rates did not differ (P=0.72) between treatments within year. Both treatments went to corn residue at the time of weaning (late January) and grazed for 37 d. A treatment × year × time interaction (P<0.01) was observed for cow BW, BCS, and calf BW. In Year 1, cow BCS at pre-calving, breeding, and weaning was less (P<0.01) for DL (5.3) than PAST (6.2; 1 to 9 scale). Weaning weights in Year 1 were less (P<0.05) for DL (178 kg) than PAST (183 kg) calves. In Year 2, cow BCS was less (P<0.01) in DL (6.1) than PAST (6.7) at pre-calving and breeding, but did not differ (P=0.12) at weaning. At weaning in Year 2, calf BW of DL (212 kg) was greater (P<0.01) than PAST (201 kg). Like Year 2, DL cows in Year 3 had decreased (P<0.01) BCS at pre-calving compared with PAST (7.3 vs. 7.7). However, breeding BCS (6.8) did not differ (P=0.98). In Year 3, cow BCS at weaning was greater (P<0.01) for DL (7.1) than PAST (5.9) but calf BW at weaning did not differ (P=0.17). Cow and calf performance are not sacrificed in semi-confined cow-calf systems and are a reasonable alternative to traditional pasture systems. [ABSTRACT FROM AUTHOR]