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 Ideas Integrated 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.

Integrated crop-livestock (ICL) system is beneficial in enhancing soil organic carbon and nutrient cycling. However, the benefits of the ICL system on mitigation of GHG emissions are poorly understood. Thus, the present study was initiated in 2011 to assess the effect of crop rotation diversity and grazing managed under the ICL system on GHG emissions. The cropping system investigated here included spring wheat grown continuously for five years and a 5-yr crop rotation (spring wheat-cover crops-corn-pea/barley-sunflower). Each phase was present each year. Yearling steers grazed only the pea/barley, corn and cover crops plots in 2016 and 2017. Exclusion areas avoided the grazing in these crops to compare the GHG fluxes under grazed vs. non-grazed areas. The GHG fluxes were measured weekly from all crop phases during the growing season for both years using a static chamber. Cumulative CO 2 and CH 4 fluxes were similar from all crop phases over the study period. However, continuous spring wheat recorded higher cumulative N 2 O fluxes (671 g N ha -1 ) than that under spring wheat in rotation (571 g N ha -1 ). Grazing decreased cumulative CO 2 fluxes (359 kg C ha -1 ) compared to ungrazed (409 kg C ha -1) , however, no effect from grazing on cumulative CH 4 and N 2 O fluxes over the study period were found. The present study shows that grazing and crop rotational diversity affected carbon and nitrogen inputs, which in turn affected soil CO 2 and N 2 O fluxes. Long-term monitoring is needed to evaluate the response of soil GHG emissions to grazing and crop rotation interactions under the ICL system.

Increasing crop diversity has been highly recommended because of its environmental and economic benefits. However, the impacts of crop diversity on soil properties are not well documented. Thus, the present study was conducted to assess the impacts of crop diversity on selected soil quality indicators. The cropping systems investigated here included wheat (Triticum aestivum L.) grown continuously for 5 years as mono-cropping (MC), and a 5-year cropping sequence [(wheat–cover crop (CC)–corn (Zea mays L.)–pea (Pisum sativum L.) and barley (Hordeum vulgare L.)–sunflower (Helianthus annuus L.)]. Each crop was present every year. This study was conducted in the northern Great Plains of North America, and soil quality data were collected for 2016 and 2017. Selected soil quality indicators that include: soil pH, organic carbon (SOC), cold water-extractable C (CWC) and N (CWN), hot water-extractable C (HWC) and N (HWN), microbial biomass carbon (MBC), bulk density (BD), water retention (SWR), wet soil aggregate stability (WAS), and urease and β-glucoside enzyme activity were measured after the completion of 5-year rotation cycle and the following year. Crop diversity did not affect soil pH, CWC, CWN, HWC, HWN and SWR. Cropping systems that contained CC increased SOC at shallow depths compared to the systems that did not have CC. Crop diversity increased WAS, MBC, and urease and β-glucoside enzyme activity compared with the MC. Comparison of electrical conductivity (EC) measured in this study to the baseline values at the research site prior to the establishment of treatments revealed that crop rotation decreased EC over time. Results indicate that crop diversity can improve soil quality, thus promoting sustainable agriculture.

In a 2-yr study, spring-born yearling steers (n = 144), previously grown to gain <0.454 kg·steer-1·d-1, following weaning in the fall, were stratified by BW and randomly assigned to three retained ownership rearing systems (three replications) in early May. Systems were 1) feedlot (FLT), 2) steers that grazed perennial crested wheatgrass (CWG) and native range (NR) before FLT entry (PST), and 3) steers that grazed perennial CWG and NR, and then field pea-barley (PBLY) mix and unharvested corn (UC) before FLT entry (ANN). The PST and ANN steers grazed 181 d before FLT entry. During grazing, ADG of ANN steers (1.01 ± SE kg/d) and PST steers (0.77 ± SE kg/d) did not differ (P = 0.31). But even though grazing cost per steer was greater (P = 0.002) for ANN vs. PST, grazing cost per kg of gain did not differ (P = 0.82). The ANN forage treatment improved LM area (P = 0.03) and percent i.m. fat (P = 0.001). The length of the finishing period was greatest (P < 0.001) for FLT (142 d), intermediate for PST (91 d), and least for ANN (66 d). Steer starting (P = 0.015) and ending finishing BW (P = 0.022) of ANN and PST were greater than FLT steers. Total FLT BW gain was greater for FLT steers (P = 0.017), but there were no treatment differences for ADG, (P = 0.16), DMI (P = 0.21), G: F (P = 0.82), and feed cost per kg of gain (P = 0.61). However, feed cost per steer was greatest for FLT ($578.30), least for ANN ($276.12), and intermediate for PST ($381.18) (P = 0.043). There was a tendency for FLT steer HCW to be less than ANN and PST, which did not differ (P = 0.076). There was no difference between treatments for LM area (P = 0.094), backfat depth (P = 0.28), marbling score (P = 0.18), USDA yield grade (P = 0.44), and quality grade (P = 0.47). Grazing steer net return ranged from an ANN system high of $9.09/steer to a FLT control system net loss of -$298 and a PST system that was slightly less than the ANN system (-$30.10). Ten-year (2003 to 2012) hedging and net return sensitivity analysis revealed that the FLT treatment underperformed 7 of 10 yr and futures hedging protection against catastrophic losses were profitable 40, 30, and 20% of the time period for ANN, PST, and FLT, respectively. Retained ownership from birth through slaughter coupled with delayed FLT entry grazing perennial and annual forages has the greatest profitability potential.

Feed contamination by fungi can lead to nutrient losses and detrimental effects on animal health and production. The presence of nitrates and nitrites in food can be harmful to both people and animals. The aim of this study was to determine total aflatoxin, nitrate and nitrite levels in layer feed samples from companies producing their own feed in Edincik and Bandırma provinces in Turkey and to discuss the potential risk to animal health. The results of the analyses indicated that mean total aflatoxin (AFT) ranged from 0.4 to 36.8 µg kg(-1) and from 0.45 to 47.0 µg kg(-1) in the year 2007 and the year 2008 samples, respectively. It was determined that nitrate levels were 2.4-10 and 1.7-13 µg kg(-1) and that nitrite levels were 0-2.4 µg kg(-1) and 0-2.6 µg kg(-1) in these years, respectively. The levels of total aflatoxin, nitrate and nitrite in the layer samples could not be considered a risk to poultry health and productivity.

SummaryThis study objective was to compare the effect of feeding field pea, flaxseed and field pea-flaxseed combination on steer performance and immune response during the 50-d post-weaning period (PWP). Subsequently, the effect on feedlot finishing performance, immune response and carcass quality were determined. Crossbred Angus x Hereford x Gelbvieh steers (castrated male calves, age=7.4 month, n=173) were used in the 3 year replicated study. The four pelleted 50-d PWP diets (PWD) were: 1) Control (C), 2) 12.5% Flaxseed (FLX), 3) 20.0% Field Pea (P), and 4) 20.0% Field Pea + 12.5% Flaxseed (PFLX). In the PWP, average daily weight gain (ADG) was increased (P<0.05) for FLX and PFLX when compared with C and P, but feed cost/kg of gain for FLX and PFLX was decreased (P<0.05). In the feedlot period, initial weight, slaughter weight, fattening period, weight gain, ADG, average daily feed intake and feed conversion ratio was not significantly different among the diets (P>0.10). For carcasses, PWD did not affect hot carcass weight, marbling score, percent US Department of Agriculture quality grade (P>0.05); however, FLX treatment reduced rib-eye area (REA), while P treatment increased REA (P<0.05). FLX and PFLX treatments did not increase serum neutralization titer level and did not reduce morbidity (P=0.96) and health care cost (P>0.10). Overall, Flaxseed improved 50-d PWP performance, but PWDs had no carryover effect on feedlot finishing period net return. Keywords ÖzetBu çalışmanın amacı, 50 gün boyunca sütten kesim sonrası periyot (PWP)'ta rasyona ilave edilen keten tohumu, yemlik bezelye ve keten tohumuyemlik bezelye kombinasyonun danaların besi performansı ve bağışklık sistemi üzerine etkisini karşılaştırmaktır. Bunu takiben, besi sonu performansı, karkas kalitesi ve bağışılık sistemi üzerine etkisini belirlemektir. Üç yıl tekrarlanan bu çalışmada melez Angus x Hereford x Gelbvieh danaları (kısırlaştırılmış erkek dana, yaş=7.4 ay, n=173) kullanılmıştır. 50 günlük PWP rasyonları (PWD); 1) Kontrol (C), 2) %12.5 Keten tohumu (FLX), 3) %20.0 yemlik bezelye (P) ve 4) %20 yemlik bezelye + %12.5 keten tohumu (PFLX) olarak dört grupta peletlenmiştir. PWP'da FLX ve PFLX gruplarında günlük canlı ağırlık artışı (ADG) daha yüksek (P<0.05) ve birim ağırlık artışı için yem maliyeti daha düşüktür (P<0.05). C ve P gruplarında ADG (P=0.004) daha düşüktür. Besi döneminde; başlangıç ağırlığı, kesim ağırlığı, besi süresi, canlı ağırlık artışı, ADG, ortalama günlük yem tüketimi, yemden yararlanma oranında farklılık görülmemiştir (P>0.10). Karkas ölçümlerinde, PWD'leri sıcak karkas ağırlığını, kas içi yağ dağılımını, ve USA Tarim Bakanlığı kalite derece yüzdesini etkilememiştir (P>0.05); bununla birlikte, P grubunda sırt kası alanı (REA) artarken, FLX grubunda REA azalmıştır (P<0.05). FLX ve PFLX gruplarında serum nötralizasyon titre seviyesi artmamış ve morbidite oranı (P=0.96) ve tedavi maliyetleri (P>0.10) önemli ölçüde düşmemiştir. Genel olarak, keten tohumu 50-d PWP performansını artırmıştır, ancak PWD'nin daha sonraki besi bit...

When selling small-framed steers at weaning, profitability is diminished. The hypothesis is that by using a vertically integrated business model that includes retained ownership, extended grazing, abbreviated feedlot finishing, and selling at slaughter, profitability would increase. Crossbred yearling steers (n = 288) from small size Aberdeen Angus (Lowline) × Red Angus × Angus × Angus cows and moderate to large size Red Angus × Angus × Simmental × Gelbvieh cows calved May−June were randomly assigned (complete randomized design), in a 3 y study, to feedlot control (FLT) and extended grazing (GRZ) frame score treatment groups. Mean frame score for FLT were small frame (SF) 3.82 and large frame (LF) 5.63, and for GRZ, SF: 3.77 and LF: 5.53. Least-square means were utilized to identify levels of effects and to control family-wise error adjusted with Tukey test. The FLT control steers were housed in the feedlot and fed growing diets and subsequently high energy corn-based diets for 218 days. The GRZ steers grazed a sequence of forages (native range, field pea-barley mix, and unharvested corn) for 212 days and then were transferred to the feedlot and fed high energy corn-based finishing diets for 82 days. The SF GRZ steers grew more slowly grazing native range and annual forages compared to GRZ LF steers, but SF steer grazing cost per kg of gain was reduced 7.80%. Grazing steers did not grow to their full genetic potential. Slower growth during grazing allowed LF and SF steers to grow structurally before feedlot entry creating a compensatory feedlot finishing growth response. Overall, grazing steer performance exceeded steer performance of the FLT control treatment and LF grazing steers had the highest rate of gain, and lowest feed cost per kg of gain. The GRZ steer feedlot days on feed were reduced 136 days and total feed intake was reduced resulting in LF and SF grazing steer feed cost reductions of 175.9 and 165.3%, respectively. Extended grazing also resulted in LF and SF grazing steer hot carcass weights to be greater than control LF and SF steers and SF grazing steers had greater dressing percent, and marbling score. Carcass quality grade, meat tenderness, and cooking losses were similar. System net returns were highest for LF (USD 911.58), and SF (USD 866.61) grazing steers. Managerial modification combining retained ownership, extended grazing, and delayed feedlot entry increased profitability and eliminated market bias.

In a grass-fed system grazing study, yearling crossbred Aberdeen Angus x Red Angus x Angus x Angus steers (n = 72; 3 reps/8 steers/rep) were assigned to either a grass-fed annual forage (GFANN) or a grass-fed native range (GFNR) system, and compared with a NR feedlot control system (FLT), in a delayed feedlot entry program, to determine the effect of grazing and feedlot finishing performance, carcass measurements, and systems net return. Data were analyzed using the MIXED procedure of SAS. After 176.0 grazing days, GFANN, GFNR, and FLT steers were transitioned to free-choice cover crop hay bale feeding (BGRZ) and 3.09 kg daily of a wheatmidd-based supplement (SUP). GFANN and GFNR received hay and SUP for 92 d; FLT control steers received hay and SUP for 69 d before transfer to the University of Wyoming feedlot. Grass-fed and FLT steers were harvested at federally inspected abattoirs in Green Bay, WI, and Ft. Morgan, CO, respectively. BGRZ gain and ADG for GFANN and FLT were greater than GFNR (P = 0.075; P = 0.072). When GFANN and GFNR bale grazing finishing costs were combined with FLT cost, feed cost/unit of gain were greater for GFANN and GFNR compared with FLT (P = 0.006). Steer FLT HCW was 26% and 34% heavier (P = 0.001), marbling score was 32% and 38% greater (P = 0.001), and carcass value was 16% and 24% greater (P = 0.001) than GFANN and GFNR, respectively. Net return was -$88.25, $62.70, and $160.22 for GFANN, GFNR, and FLT, respectively. Farming and long-haul transportation cost for GFANN and GFNR negatively affected net return.