Grass Hay Research Articles

Ameliorating Forage Crop Resilience in Dry Steppe Zone Using Millet Growth Dynamics

Introducing new forage crops such as Japanese millet (Echinochloa frumentacea) and pearl millet (Pennisetum glaucum) is crucial for mitigating the impacts of climate change in the dry steppe zone, expanding forage crop options, and obtaining nutritious feed for the development of animal husbandry. The aim of this study was to assess the productivity and feed value of these crops. Field experiments were conducted in 2021 and 2022 to investigate the changes and variations in the yields and chemical compositions of Japanese millet and pearl millet when grown as sole crops or in mixed cropping in the dry steppe zone of northern Kazakhstan. Among the annual crops sown via sole cropping, the hay of the Japanese millet, sown in the third decade of May and harvested during full heading, was observed to have a higher content of raw protein and other nutrients than Sudanese grass hay, that is, the raw protein content was higher at 1.81%, the raw oil content at 0.12, and the raw ash content at 1.88%. In addition, among the mixtures of crops, the hay of the crop mixtures containing pearl millet, sown in the above period and harvested as hay during the milky stage, the full heading stage, and the formation of spikelets in the grain family stage, differed from the hay of Sudanese grass sown in the same period and collected during full heading in terms of the contents of raw protein and other nutrients and the low content of raw ash, that is, the content of raw protein was at 2.16%, raw oil at 0.39, raw ash at 0.95, without nitrogen extractives (WNEs) at 3.78, and starch at 0.11. The calcium content was higher by 0.08% and carotene by 0.11 mg/kg, and raw lentils were lower by 0.94%. The analysis of the results revealed that the variation in the crops’ phenological phases depended on the moisture availability and the sowing time.

Hay meadows in the High Weald of Sussex

SummaryThe ancient hay meadows at Wakehurst, Kew's wild botanic garden, are described, and many of the species which go to make up these High Weald grasslands are illustrated. Native Sussex hay meadows and North American prairie grasslands are compared.

Extensive dune grasslands largely lacking human disturbance are an important refuge for a vole-dependent raptor

Agricultural intensification and abandonment have led to a dramatic decrease of semi-natural grasslands such as low-intensity pastures and hay meadows. The Short-eared owl (Asio flammeus) is a ground-nesting raptor of open grasslands that has severely suffered from these changes. We studied the habitat preferences of this umbrella species of open grasslands in its last permanent breeding area in Germany (East Frisian Islands, southern North Sea). We analysed the breeding-territory preferences based on 576 territories on six of the islands. Moreover, we assessed nest-site preferences of 13 breeding pairs on the German abundance hot spot, the island of Spiekeroog. Our investigation revealed that the Short-eared owl strongly preferred open dunes for breeding, especially dune grasslands. By contrast, built-up areas and small stands of trees were avoided. For nest-building, microhabitats with a high cover of the herb layer and litter resulting in tall vegetation were favoured. By contrast, the vegetation in the wider surrounding of the nest was characterised by more bare ground and shorter vegetation but still a high cover of the herb layer and litter. In conclusion, our study highlights the prime importance of extensive open grasslands with a pronounced litter layer and largely lacking human disturbance as breeding habitats for the Short-eared owl. At the nesting site, we suggest that tall and dense vegetation with a high cover of litter (i) might enhance concealment and (ii) causes a favourable microclimate by protecting fledglings against adverse weather conditions. In the wider surrounding of the nest, shorter vegetation with a pronounced litter layer (i) improves fledgling mobility, (ii) fosters vole abundance and (iii) increases prey accessibility.

Immunobiological reactivity of calf body during the compatible application of nanotechnological citrates of trace elements in the ration

Background. Nanotechnology in animal husbandry is an important area of research and development, which includes environmental sustainability, human health and food security. Nanotechnology has the potential to solve many questions related to animal health, production, reproduction, good hygienic practices during rearing and maintaining of animals. Therefore, the research aimed to find out the biological effect of separate and combined feeding of nanotechnological citrates that show high physiological activity in doses much lower than their mineral salts. Materials and Methods. The research was conducted on 15 heifers and bulls divided into three groups five days after birth: control (I) and experimental (II, III) ones, five animals in each. Calves of group I received 240 kg of natural milk with the addition of a mineral-concentrate supplement (MCS) and grass hay for 60 days. Calves of group II were fed similar feed to that of group I with the replacement of MCS with a nutritionally equivalent quantity of cereal grains and soybeans and the introduction of nanotechnological citrates of microelements (NTC ME) I, Se, Cr, Cu, Co, Mn, Zn, Fe into milk in the proportion of 10 %. Calves of group III were fed with a complex of feeds of group I, adding 10 % of NTC ME. Physiological and biochemical indicators of blood and wool of calves were studied on the 10th, 40th and 70th days of growing period. Results. Statistically significant changes in the immunobiological indicators of the blood of calves of group II were found with an increase in the concentration of circulating immune complexes, haptoglobin, and sialic acids in the blood on the 40th day and ceruloplasmin, sialic acids, hexoses bound to proteins and chromium on the 70th day. An increase in the detoxification function of the calves’ liver was recorded, with an increase in the blood level of phenol sulfates by 11.2 % and phenol glucuronides by 18.8% during this period. The combined use of 10 % NTC microelements and MCS in feeding calves of group III led to a statistically significant increase in the blood content of circulating immune complexes, phenol sulfates, phenol glucuronides, and zinc on the 40th and 70th days compared to their level in animals of the control group. Body weight gain in calves of group II was higher by 7.7 %, and in group III – by 4.3 % compared to the control. Conclusion. The addition of NTC ME in the amount of 10 % of the rationed food for these elements to the milk for calves of group II, with the exclusion of the mineral-concentrate supplement from the feeding scheme, led to the activation of the immunobio­logical reactivity of the organism. The combined use of 10 % of NTC ME and mineral-concentrate supplement in the diet of calves of group III resulted in a lesser immunobiological reactivity of the organism, and strengthened the detoxification ability of the body.

Insect-friendly harvest in hay meadows – Uncut refuges are of vital importance for conservation management

With ongoing industrialisation of farming practise, the area of species-rich temperate grasslands has strongly declined. Today, the remnants of these grasslands often suffer from habitat degradation due to unsuitable management. Here, we investigated the effects of the complete harvest process over the course of two harvest periods (mid-June and mid-August) on Orthoptera (hereinafter referred to as ‘grasshoppers’) in species-rich lowland hay meadows in southwestern Bavaria (Germany). We set up a randomised split-plot design including mown meadows (tractor-operated rotary-disc vs. double-bladed bar mower) and uncut refuges within grassland patches. Our study revealed that mower types did not differ in their effects on grasshopper mortality and that direct mortality through cutting was very low. By contrast, after mowing, on average 85–91 % of the individuals or biomass was lost by the end of the harvest process. However, in uncut refuges, grasshopper densities and biomass increased on average by 234–328 %. From the first to the second harvest period, an alignment in grasshopper densities and biomass between meadows and uncut refuges occurred. We explain the lack of direct cutting effects by the tall and dense vegetation of the hay meadows and, hence, the location of the grasshoppers far above the sphere of the mowers. Moreover, we assume that in particular emigration from the short and homogeneous meadows to uncut refuges or patch edges but also increased vertebrate predation were responsible for the severe grasshopper losses. Moreover, we hypothesise that grasshopper recolonization from the refuges to the meadows strongly contributed to the alignment in grasshopper densities from mid-June to mid-August. Hence, to protect abundant grasshopper populations in meadows in the long run, uncut refuges are of prime importance. Firstly, such refuges guarantee a continuity in (i) food resources, (ii) a balanced microclimate and (iii) shelter against predators and extreme weather events for the resident individuals. Consequently, they are not affected by any of the harvest-related losses. Secondly, they serve as an important refuge for the emigrants from the mown parts of the meadow.

PSIV-13 Influence of Differing Levels of Concentrate on Circulating Cytokine Concentrations in Beef Heifers

Abstract Components of the immune system, such as cytokines and chemokines, can influence female reproductive efficiency. Recently, studies have begun to characterize the influence of nutrition on cytokines and reproductive function. Characterizing the influence of nutritional components on shifting circulating cytokine concentrations will allow for a better understanding of reproductive efficiency in cattle. The objective of this study was to determine the effect of diet composition on cytokine concentrations in blood plasma in beef heifers. Using a 3 x 3 Latin square design, fifteen rumen-cannulated, pubertal Bos taurus-influenced heifers were fed a diet based on ranging concentrate percentages. Their treatment period consisted of 28-day feeding periods with a washout interval of 21 days. The treatment groups were fed 100% grass hay (high forage; HF), 60% grass hay with 40% corn-based concentrate (intermediate; INT), and 25% grass hay with 75% corn-based concentrate (high grain; HG) within their respective treatment group. Heifers were offered 2% of their body weight daily. Blood was collected on days 0 and 28 of the treatment period for cytokine analysis. Plasma cytokine concentrations were quantified using RayBiotech Quantibody Bovine Cytokine Array Q1 kit according to manufacturer instructions. Data analysis was conducted using orthogonal contrasts (linear and quadratic) with day 0 as independent covariates and heifers as the experimental unit. There were no significant quadratic contrasts. Concentrations of interferon gamma-induced protein 10 (IP-10) linearly decreased with an increased concentrate diet (P = 0.04). Concentrations of IP10 significantly differed for heifers consuming the HF diet versus the HG diet (3,069.5 ± 672.2 vs. 1,001.8 ± 669.3 pg/mL, respectively) and heifers consuming the INT diet versus the HG diet (2,886.8 ± 665.6 vs. 1,001.8 ± 669.3 pg/mL, respectively); however, there were no significant differences in IP10 concentrations between the HF and INT heifers. Interferon-gamma (IFNg) concentrations significantly differed between feeding periods with period 2 having the least circulating concentrations when compared with periods 1 and 3 (5.2 ± 66.2 vs. 183.4 ± 68.4 and 221.3 ± 67.8 pg/mL, respectively; P < 0.05). Additionally, monokine induced by gamma interferon (MIG) significantly differed by period with period 2 having the least circulating concentrations compared with periods 1 and 3 (862.2 ± 285.4 vs. 1675.8 ± 283.4 and 1,170.8 ± 286.9 pg/mL, respectively; P < 0.05). Interestingly, both IP10 and MIG are chemokines, or small cytokines with chemotactic functions, that are secreted by immune cells in response to IFNg. Results suggest that heifers consuming a high concentrate diet have decreased concentrations of circulating cytokines, specifically IP10. Additionally, in the current study, cytokines that were influenced were associated with IFNg. Further research is necessary to better comprehend the dietary influence on the immune system in developing heifers and how this is associated with reproductive efficiency.

PSII-2 Effects of Natural Sources of Brackish/Saline Water on Water and Feed Intake, Digestion, Physiological Conditions, and Performance of Yearling Meat Goats

Abstract This experiment was aimed to determine how variables such as water intake, feed intake, ruminal conditions, digestion, blood constituent levels, energy metabolism, and performance of yearling meat goats are influenced by different natural sources of brackish/saline water. Two animal types (AT), 18 Boer (BOE) and 18 Spanish (SPA) doelings, with the age of 8.9 ± 0.306, and 9.7 ± 0.212 months, respectively were used for the experiment which lasted 17 weeks (16 weeks for the experiment and 1 week of adaptation). Drinking water treatments were fresh water (FRW), West pasture Brackish water (BRW), water classified by USGS as group 1 (GR-1), 2 (GR-2), 3 (GR-3), and the last one did not fit well with any USGS group (G-UC). Animals were fed a medium-quality grass hay primarily consisting of lespedeza and with some Johnson grass (12.2% CP, and 48% NDF on a DM basis) and a supplement was provided at 0.2% BW (DM basis) to supply trace minerals, vitamins, and protein. Average daily gain was similar (P > 0.05) among treatments (16.3, 20.1, 21.1, 20.7, 23.3, and 26.5 g/day SEM = 6.378 for FRW, BRW, GR-1, GR-2, GR-3 and G-UC, respectively), and between AT (19.9 and 22.7 g/day SEM = 3.90 for BOE and SPA, respectively). Treatment did not affect water (P = 0.752; 830, 767, 821, 796, 855, and 857 g/day; SEM = 47.86) or hay intake (P = 0.862; 682, 654, 641, 674, 650, and 689 g/day SEM = 31.72), and also there were no differences between AT in intakes of water (P = 0.157; 850 and 793 g/day; SEM = 27.63) and hay (P = 0.165; 684 and 647 g/day SEM = 18.31) for BOE and SPA, respectively. Treatment had no effect on blood packed cell volume (PCV; P = 0.224; 28, 27.4, 29.7, 25.7, 26.2, 27.5%), hemoglobin concentration (tHb; P = 0.489; 11.2, 10.6, 11.2, 10.4, 10.3, 10.6 g/dL) or osmolality (310, 310, 309, 310, 309, and 309 mOsm/L) for FRW, BRW, GR-1, GR-2, GR-3 and G-UC, respectively. But there were differences between AT in PCV (P < 0.001; 24.8 and 30%) and tHb (P < 0.001; 9.71 and 11.7 g/dL) for BOE and SPA, respectively. Animal types differed in their heat (P = 0.046; 3.94 and 3.70 MJ/day; SEM = 0.081) and methane production (P < 0.001; 0.50 and 0.42 MJ/day; SEM = 0.014) for BOE and SPA, respectively; but treatment did not affect heat energy (P = 0.861; 3.84, 3.77, 3.67, 3.88, 3.88, 3.86 MJ/day SEM = 0.1409) or methane energy (P = 0.634; 0.46, 0.43, 0.45, 0.47, 0.48, 0.48; SEM = 0.0241) for FRW, BRW, GR-1, GR-2, GR-3 and G-UC, respectively. Though differences existed between animal types, considering lack of effect of drinking water used in the studied parameters, the animals seemed resilient to the brackish water from West pasture, USGS group 1, 2, 3 and the unclassified water.

264 Evaluation of Precision Feeding on Production Efficiency Responses in Finishing Beef Cattle

Abstract Charolais-Angus cross steers (n = 128; initial shrunk BW = 505 ± 32.1 kg; n = 16 pens; 8 replicate pens/treatment) were used in a 94-day finishing phase experiment to evaluate animal growth performance outcomes, efficiency measures, and carcass characteristics when varying degrees of ingredient inclusion tolerances were imposed. Treatments included: 1) Normal feeding with 0.454 kg tolerance for all ingredients (FXD) and 2) Variable inclusion strategy where each ingredient was randomly increased or decreased but the targeted as-fed quantity for the daily delivery was met (VAR). All steers were fed twice daily with all bunks managed using a slick bunk approach. Ractopamine HCl was fed (300 mg per head daily) for the final 28 d. Individual BW measures were captured at processing approximately every 35 d. Diets consisted of high-moisture corn (HMC), dry-rolled corn (DRC), dried distillers grains plus solubles (DDGS), liquid supplement (LS), and grass hay (GH) for the first 40 days of the finishing period. Days 41-94 diets consisted of DRC, LS, DDS, GH, and corn silage (CRNSIL). Ingredient inclusions were randomized by assigning independently a random integer to HMC, GH and DDGS with each integer corresponding to the deviation from targeted inclusions; LS inclusion was held constant. As-fed inclusion rates varied from formulated targets by -20, -15, -10, -5, 0, +5, +10, +15, or +20%. DRC or CRNSIL was adjusted so that the targeted as-fed amount of the diet was delivered each day. Data were analyzed using the GLIMMIX procedure of SAS 9.4 (SAS Inst. Inc., Cary, NC) with pen as the experimental unit and block as random effect. VAR steers had increased (P ≤ 0.01) dry matter intake (DMI) and reduced (P ≤ 0.02) kg of gain to kg of feed (G:F). However, no differences (P = 0.75) were detected between treatments for ADG. In addition, net energy for maintenance and gain was decreased (P ≤ 0.01) in VAR. Carcass characteristics for both treatments showed no significance (P ≥ 0.38) in HCW, dressing percentage, rib eye area, rib fat, KPH, yield grade, retail yield, empty body fat, or body weight at 28% estimated EBF. A tendency for increased USDA marbling score (P > 0.08) was noted in VAR. Under the conditions of this experiment, randomly altering ingredient proportions did impact growth performance and efficiency measures. However, despite the difference in growth efficiency carcass characteristics were not impacted.

PSV-14 Effects of Forage or Coproduct-Based Transition Diets on the Rumen Microbiome and Ruminal Fermentation ex Vivo in Feedlot Steers

Abstract The objective was to determine the effect of replacing forage with coproducts in transition diets on rumen microbiome composition and ruminal fermentation ex vivo after steers consumed a common finishing diet. A random subset of 30 steers were selected from a larger, separate pen study. Steers were blocked by initial BW and allotted into 9 pens. Pens were then assigned to 1 of 3 dietary treatments for the 35 d adaptation period: a forage-based diet (FO; alfalfa and grass hay), a coproduct-based diet (CO; soybean hulls and modified wet distillers grains with solubles), and a coproduct-based diet pair-fed (CO-P) to isoenergetic levels of FO. Dry-rolled corn inclusion increased with either decreasing forage or coproduct inclusion. Both FO and CO were fed with slick bunk management. At d 35 and 63, rumen fluid was collected by esophageal tubing to determine differences in fermentation of the finishing diet as the substrate in an ex vivo model. Rumen fluid was also utilized for microbiome analysis using 16S rRNA sequencing on the Illumina MiSeq platform with 2 × 300 bp paired-end sequencing. Sequencing reads were analyzed within QIIME2. Statistical analyses were conducted using SAS 9.4. Fermentation data were analyzed using the MIXED procedure, while bacterial relative abundance data were analyzed in the GLIMMIX procedure. Correlations were analyzed using the CORR procedure. A treatment × sampling day interaction (P = 0.02) was observed for in vitro dry matter disappearance; on d 35, it was greater in steers fed CO compared with CO-P (58 vs. 53%, respectively), but no differences were observed on d 63. Within the rumen microbiome, there was a tendency (P = 0.06) for alpha diversity to have a treatment × day interaction. Specifically, CO steers had the greatest decrease in alpha diversity from d 35 to 63, but there was no change in alpha diversity in FO steers and CO-P steers over time. Final pH in from the ex vivo model was positively correlated (r = 0.32) with Bacteroidetes relative abundance but negatively correlated (r = -0.25) with Proteobacteria (P ≤ 0.05). In vitro dry matter disappearance was positively correlated (r = 0.38) with relative abundance of Firmicutes, but negatively correlated (r = -0.43) with Proteobacteria (P < 0.01). Dietary treatment did not affect (P ≥ 0.21) richness within the rumen microbiome. Rumen microbiome composition and ex vivo fermentation results suggest all treatments were adapted for the finishing diet at the conclusion of the 35-d adaptation period.

97 Effects of Creep Feed Duration in a Drylot System on Cow Performance and Reproduction as Well as Calf Performance Through Receiving

Abstract The objectives were to determine effects of creep feed duration in drylot-housed, cow-calf system on cow performance and reproduction as well as calf performance through receiving phase. Spring-calving, Simmental × Angus cows (5 ± 2 yr; n = 72) were stratified by calf age (83 ± 14 d), sex, and body weight (BW; 130 ± 17 kg) and allotted to 12 pens with six cow-calf pairs per pen. Pens were randomly assigned to 1 of 2 treatments: calves fed commercial, pelleted creep feed (14% CP) for 105 d (105dCF) or final 21 d (21dCF) prior to weaning. Cow-calf pairs were housed on concrete drylots with open-front buildings for the pre-weaning period. Cows were limit fed at maintenance a total mixed ration. Ultrasound measurements for carcass composition of calves were collected on d 104. Calves were abruptly weaned on d 105 and transported 263 km to a feedlot for the receiving phase. Pen assignments remained for the 6-week receiving period. Calves had ab libitum access to a receiving ration that consisted of corn silage, modified wet distillers grains, grass hay, dry corn, and supplement. Reproduction data were analyzed using GLIMMIX and all other response variables were analyzed using the MIXED procedure of SAS 9.4. There were no differences (P ≥ 0.11) in cow BW, BCS, milk production, milk composition, or reproductive data. The 105dCF calves had greater (P ≤ 0.01) ADG from d 0 to 105 and BW than 21dCF (286 vs. 258 kg, respectively). The 105dCF calves had greater (P ≤ 0.01) longissimus muscle area, rib fat, and rump fat compared with 21dCF; however, intramuscular fat was not different (P = 0.20) between treatments. During the receiving phase, there were no differences (P ≥ 0.23) in dry matter intake. In the first 4 weeks of receiving there were no differences (P ≥ 0.73) in ADG; however, in the final 2 weeks 21dCF calves had greater (P = 0.02) ADG. The 21dCF calves had greater (P = 0.01) ADG during the overall receiving period. There were no differences (P ≥ 0.86) in gain to feed (G:F) for the first four weeks of receiving. The 21dCF calves had greater (P = 0.03) G:F for the final two weeks and tended to have greater (P = 0.08) G:F during overall receiving. However, the 21dCF calves (324 kg) were still lighter (P ≤ 0.01) BW than 105dCF (340 kg) at end of receiving. In conclusion, creep feed duration did not impact cow performance or reproduction. The 105dCF calves had increased ADG and BW for the pre-weaning period. Although the 21dCF calves had increased gain and feed efficiency at the end of receiving, the 105dCF calves remained the heavier for the duration of the experiment.

PSV-12 Effects of Diet on Feed Intake, Weight Change, and Gas Emissions in Beef Cows

Abstract The objective of this study was to examine the effects of diet energy density on ranking for dry matter intake (DMI), residual feed intake (RFI), and greenhouse gas emissions. Forty-two mature, gestating Angus cows [600 ± 69 kg body weight (BW); body condition score (BCS) 5.3 ± 1.1] with a wide range in DMI expected progeny difference (−1.38 to 2.91) were randomly assigned to two diet sequences; forage then concentrate (FC) or concentrate then forage (CF). The forage diet consisted of long-stem native grass hay plus protein supplement (HAY; 1.96 Mcal ME/kg DM). The concentrate diet consisted of 35% chopped grass hay and 65% concentrate feeds on a dry matter basis (MIX; 2.5 Mcal ME/kg DM). The GreenFeed Emission Monitoring system was used to determine carbon dioxide (CO2), oxygen (O2), and methane (CH4) flux. Cow performance traits, ultrasound back fat and rump fat, feed DMI, and gas flux data were analyzed in a crossover design using a mixed model including diet, period, and sequence as fixed effects and pen and cow within sequence as random effects. For all measured traits excluding DMI, there was a diet × sequence interaction (P < 0.05). The correlation between MIX and HAY DMI was 0.41 (P = 0.067) and 0.47 (P = 0.03) for FC and CF sequences, respectively. There was no relationship (P > 0.66) between HAY and MIX average daily gain (ADG), regardless of sequence. Fifty-seven percent of the variation in DMI was explained by metabolic BW, ADG, and BCS for both diets during the first period. During the second period, the same three explanatory variables accounted for 38% and 37% of the variation in DMI for MIX and HAY diets, respectively. The negative relationship between BCS and DMI was more pronounced when cows consumed the MIX diet. There was no relationship between MIX and HAY RFI, regardless of sequence (P > 0.18). During the first period, correlations for CO2, CH4, and O2 with MIX DMI were 0.69, 0.81, and 0.56 (P ≤ 0.015), respectively, and 0.76, 0.74, and 0.64 (P < 0.01) with HAY DMI. During the second period, correlations for CO2, CH4, and O2 with MIX DMI were 0.62, 0.47, and 0.56 (P ≤ 0.11), respectively. However, HAY DMI during the second period was not related to gas flux (P > 0.47). Results from this experiment indicate that feed intake of two energy-diverse diets is moderately correlated while ADG while consuming the two diets is not related. Further experimentation is necessary to determine if gas flux data can be used to predict feed intake in beef cows.

PSII-1 Evaluation of Precision Feeding on Animal Behavior in Finishing Beef Cattle

Abstract Charolais × Angus cross steers (n = 80; initial shrunk BW = 505 kg ± 31.6 kg; n = 10 pens; 5 replicate pens/treatment) were used in two 24-hour observations to evaluate animal behavior based on varying degrees of daily feed inclusion over a 28-day period (d 14 and d 42 on feed). Treatments included: 1) A fixed diet inclusion rate for each individual ingredient with a tolerance of 0.454 kg, and 2) Variable inclusion rates (VAR) of diet ingredients that were randomly increased or decreased while maintaining the targeted daily as-fed delivery. Steers were fed twice daily with a slick bunk approach used to manage feed bunks. Diets composition (DM basis) was 48% high moisture corn (HMC), 21% dry-rolled corn (DRC), 5% liquid supplement (LS), 14% dried distillers’ grains plus solubles (DDGS), and 12% grass hay (GH). In the VAR treatment inclusions of HMC, DRC, and DDGS varied independently by assigning a random integer with each integer corresponding to a specific deviation from target. Dietary inclusion of LS was fixed. Inclusion of GH was altered so that the targeted as-fed amount was delivered each day. Inclusion rates of ingredients (HMC, DRC, and DDGS) on an as-fed basis varied from the formulated diet by -20, -15, -10, -5, 0, +5, +10, +15, or +20%. Data from the two 24-hour observations were analyzed using the GLIMMIX procedure of SAS 9.4 (SAS Inst. Inc., Cary, NC) with pen as the experiment unit. Treatment was analyzed as a fixed effect and block (pen location) was a random effect in the model. Varying ingredient inclusion did not affect cattle activity, time spent drinking, resting, eating, or ruminating, or chewing behaviors (P ≥ 0.24) during the initial d 14 observation. Treatment did affect DMI the week preceding that observation period (P = 0.04). During the second 24-hour observation period activity, resting, ruminating, and chewing behaviors along with DMI were unaffected by variation in inclusion of diet ingredients (P ≥ 0.33). Varying inclusion rates of diet ingredients increased time spent drinking (P = 0.05) by 33.3% and decreased time spent eating behaviors (P = 0.01) by 9.4% at the d 42 observation point. Under the conditions of the present experiment, altering dietary ingredient proportions in a finishing diet may influence time spent drinking and eating after 42 d on feed.

312 Evaluation of Dietary Roughage Manipulation During the Feeding of Ractopamine Hydrochloride as a Method to Improve Ruminal Health and Control Liver Abscess Severity in Feedlot Steers

Abstract The objective of this study was to determine if additional roughage inclusion to feedlot steer finishing diets during the feeding of ractopamine hydrochloride (RH) is an effective method to improve rumen health and control liver abscess severity. Steers [n = 64; initial shrunk body weight (SBW) = 633 kg ± 35.1 kg] were sourced from an unrelated trial and remained in their previous study pens; pens (n = 8) were assigned to dietary treatment in a completely randomized design. All steers on trial were fed a common 7% [dry matter (DM) basis] roughage equivalent (RE) finishing diet composed of dry-rolled corn, dried distillers grains plus solubles, corn silage, and grass hay for the 58 d preceding study initiation. Steers were fitted with rumination tags to track daily rumination. Dietary treatments were CON: no diet change; and 12R: 5% (DM basis) RE addition to diet via grass hay during the feeding of RH. Steers were fed RH (300 mg/steer/d), finished on treatment diets for 28 d, and harvested at a commercial beef processor. Growth performance, efficiency of dietary net energy (NE) utilization, and continuous carcass data were analyzed with pen as the experimental unit (EU) and fixed effect of treatment. Minutes ruminating was analyzed as an analysis of covariance with individual animal as the EU, fixed effects of treatment, days on feed (DOF) and their interaction, and baseline minutes ruminating as a covariate in the model. Liver abscess prevalence, rumen health, and categorical carcass data were analyzed with the Fisher’s exact test to determine differences between treatments. No difference (P ≥ 0.19) was observed for final SBW, average daily gain, dry matter intake, feed conversion efficiency, dressing percentage, hot carcass weight, calculated yield grade, marbling score, 12th rib fat thickness, calculated empty body fat, observed dietary NE for maintenance and gain, observed-to-expected dietary NE for maintenance and gain, or distribution of liver abscess prevalence, ruminitis score, or USDA yield grade. Ribeye area tended (P = 0.10) to differ between treatments with 12R steers exhibiting a 3.5% larger ribeye. Distribution of USDA quality grade differed (P = 0.003) between treatments with 12R steers having 25% more carcasses grading USDA average choice or better. A treatment × DOF interaction (P = 0.045) was observed for minutes ruminating per day. Daily minutes ruminating was increased (P ≤ 0.05) for 12R on d 1, 2, and 20 and tended to be increased (P ≤ 0.10) for 12R on days 10, 13, 24, and 25. Inclusion of an additional 5% RE to finishing cattle diets during a 28 d RH feeding period can be a management strategy to decrease risk of digestive upsets without sacrificing growth performance or carcass quality.

PSVI-2 Economic Evaluation of Forage-Fed vs Concentrate-Fed Beef Finishing Systems

Abstract The objective of this study was to determine the price points at which it is more economical to finish beef animals on forage-based or concentrate-based diets. To accomplish this, Hereford steers (n = 21; BW = 444 ± 10 kg) were fed out on one of three diets: a long-stemmed grass hay (HAY, 10.8% CP, 2.11 Mcal ME/kg DM), an alfalfa hay diet (ALF, 20.5% CP, 2.85 Mcal ME/kg DM) or a mixed ration consisting of 30.0% corn silage, 28.0% DDGS, 30.0% rolled corn, 10.5% soybean meal, and 1.5% mineral supplement (CON, 22.0% CP, 2.90 Mcal ME/kg DM). The data were analyzed in SAS v9.4. Animals were evaluated on intake, growth, and performance measures during a 35-day feeding trial. Average daily gain (ADG) and hot carcass weight differed significantly (P < 0.05) between treatments with CON steers gaining 1.47 kg/d with a hot carcass weight of 394.8 kg, ALF steers gaining 0.77 kg/d with a hot carcass weight of 334.7 kg, and HAY steers gaining 0.1 kg/d with a hot carcass weight of 237.4 kg. Dressing percentage was significantly different between all treatments (P < 0.05). The dressing percentage was 58.2%, 54.3%, and 50.6% for CON, ALF, and HAY, respectively. The HAY diet rendered significantly lower marbling scores than ALF or CON (P < 0.05). It was concluded based on carcass quality data that there was no difference in the high-quality forage (ALF) and the concentrate diet (CON) other than diet cost and growth rate. Price per kilogram of gain was $1.42, $1.23, and $14.80 for CON, ALF, and HAY, respectively. Results of this trial are expected to indicate at what price point it becomes more economically effective to finish animals on a high-quality forage or a concentrate-based diet.

PSVI-4 The Influence of Diet Type on Beef Cattle Performance and Meat Quality Characteristics

Abstract The objective of this study was to determine the effect of diet type on feed intake in yearling steers. Hereford steers (n = 21; BW = 444 ± 10 kg) were assigned to one of three drylot pens based on initial BW. Each drylot pen was assigned to one of three diets: a long-stemmed grass hay (HAY, 10.8% CP, 2.11 Mcal ME/kg DM), an alfalfa hay diet (ALF, 20.5% CP, 2.85 Mcal ME/kg DM) or a mixed ration consisting of 30.0% corn silage, 28.0% DDGS, 30.0% rolled corn, 10.5% soybean meal, and 1.5% mineral supplement (CON, 22.0% CP, 2.90 Mcal ME/kg DM). Animals were fed daily at 0700 and 1700 h and weighed weekly at 0630 h. For the duration of the trial, animals were housed in drylot pens with ad libitum access to feed and water and had shade structures in each pen. Following a 14-day adaptation period, feed intake was recorded for 35 days. Body weight gain for diets HAY, ALF, and CON were 0.1, 0.77, and 1.47 kg/day, respectively. After the intake portion of the study was completed, an animal from each pen was slaughtered and evaluated for meat quality. Hot carcass weights for diets HAY, ALF, and CON were 237.4, 334.7, and 394.8 kg, respectively. Following 14 days aging, samples from the ribeye area were collected from each animal and subjected to sensory analysis and other assessments of quality. Data were analyzed as a completely random design in SAS v9.4. There was not a significant difference between the ALF diet and the CON diet based on assessment from Warner-Bratzler shear force, carcass yield, marbling score, and sensory assessment (P < 0.05). It was concluded that high-quality forage can achieve similar carcass quality without detrimental effects on meat quality when compared with a high concentrate diet.

Intensity of grassland management and landscape heterogeneity determine species richness of insects in fragmented hay meadows

Traditionally managed grasslands rank among the most species-rich ecosystems. However, in agricultural landscapes of Western and Central Europe, their extent has severely decreased. The remaining patches are mostly fragmented and suffer from habitat deterioration. Here, we studied the effects of environmental conditions on species richness of butterflies and grasshoppers in highly fragmented hay meadows. Our study revealed that environmental parameters at the habitat and landscape level influenced species richness of butterflies and grasshoppers in low-intensity hay meadows. In the univariable models, two groups of parameters consistently affected the number of all and threatened species: at the habitat level, species richness was fostered by structural richness, which was indicative of the overall management intensity of the grassland patches. At the landscape level, a higher number of mowing events in the landscape surrounding the hay meadows had a negative effect and higher elevations exhibiting a cooler and wetter climate had a positive effect on species richness. The former reflected the overall intensity of grassland management in the landscape and the later, together with further predictors (cover of forest, habitat connectivity, slope), the landscape heterogeneity. Consequently, the intensity of grassland management at the habitat and landscape level as well as the landscape heterogeneity, which was also related to land-use intensity, determined species richness of butterflies and grasshoppers. Based on these findings, there is an urgent need to enlarge the proportion of grasslands with low land-use intensity in the wider countryside. Additionally, conservation measures should aim at increasing landscape heterogeneity and habitat connectivity.

Diverse forage improves lipid metabolism and antioxidant capacity in goats, as revealed by metabolomics.

It is well established that promoting the balance of nutrients and plant secondary metabolites (PSM) by feeding diverse forage physiologically improves ruminant production. However, the underlying mechanism remains unclear. To investigate the physiological mechanism related to the improvement of physiological stress tolerance, ruminants were fed diverse forage. Oxidative stress markers were quantified, and serum metabolomics was performed. Six crossbred Shiba wethers (32.8±9.2kg BW) were arranged in a replicated 3×3 Latin square design. The treatments were feeding only Sudan grass hay (100% SDN); feeding a mixture of Sudan grass and alfalfa hay (70:30, SDN-ALF); and feeding a mixture of Sudan grass, timothy grass, and alfalfa hay (35:35:30; SDN-TMT-ALF). Each diet group was fed its specific diet for 21days with a 14-day adaptation period. Feed intake and digestibility, blood biochemistry, total antioxidant capacity (TAC), and superoxide dismutase (SOD) were analysed. In addition, blood serum metabolites were assessed by liquid chromatography-tandem mass spectrometry. The DM intake and DM, organic matter, and CP digestibility were higher (P<0.05) in the SDN-TMT-ALF group than in the SDN group. The TAC was higher (P<0.01) in the SDN-TMT-ALF and SDN-ALF groups (809.51 and 813.7µM, respectively) than the SDN group (720.69µM), while the SOD level was unchanged (P=0.06) among the treatments. Total serum cholesterol and NH3 levels were higher (P<0.05) in the SDN-TMT-ALF group (89.17mg/dL and 242.42µg/dL, respectively) than in the SDN group (71.00mg/dL and 89.17µg/dL). Additionally, the levels of nine metabolites in serum differed among the treatments (P<0.05). Linoleic acid (LA) and cortisone, which are related to LA metabolism and the steroid biosynthesis pathway, were upregulated by the SDN-ALF and SDN-TMT-ALF diets compared to the SDN diet, suggesting the contribution of ALF to altering the metabolites. The levels of hippuric acid, which is a metabolite of phenolic compounds, were higher (P<0.001) in the animals fed SDN, which contained higher phenolic and luteolin concentrations than the other diets. Pathway analysis suggested that the higher cortisone levels were derived from cholesterol due to upregulated glycolysis metabolism, which was positively related to increased ingestion, digestibility, and serum LA levels in animals given mixed forage. In conclusion, physiological stress tolerance in the animals was regulated by upregulation of LA and steroid hormone metabolism, which was associated with an increase in TAC rather than the ability of the animal to regulate its PSM intake.

Fit by design: Developing seed–substrate combinations to adapt dike grasslands to microclimatic variation

Abstract Sowing is a well‐established restoration technique to overcome dispersal limitation. Seed mixtures adapted to certain environmental conditions, like substrate or microclimate, are most effective to achieve functional communities. This is especially important if the restored vegetation has to protect critical infrastructure like roadsides and dikes. Here, an improved seed–substrate combination will secure slope stability, make restorations more effective and generate species‐rich grasslands. A full‐factorial field experiment addressed this topic on a dike at River Danube in SE Germany in 2018–2021. Within 288 plots, we tested three sand admixtures, two substrate depths, two seed densities and two seed mixture types (mesic hay meadow and semidry calcareous grassland) in north and south exposition and measured the recovery completeness by calculating the successional distance to reference sites, the persistence of sown species and the Favourable Conservation Status (FCS) of target species. Overall, the sown vegetation developed in the desired direction, but a recovery debt remained after 4 years, and some plots still showed similarities to negative references from ruderal sites. In north exposition, hay meadow seed mixtures developed closer to their reference communities than dry grassland mixtures to their reference. In south exposition, the sown communities established poorly, which might be due to a severe drought during establishment. This initial negative effect remained over the entire observation period. Sand admixture had a slightly positive effect on target variables, while the tested substrate depths, seed densities and seed mixture types had no effects on species persistence or FCS. Synthesis and applications: Site‐adapted seed mixtures make restoration more effective, while applying several seed–substrate combinations might foster beta diversity. Furthermore, additional management efforts are recommended, as they might be necessary to reduce the recovery debt, as well as re‐sowing after unfavourable conditions like droughts.

AGROTECHNOLOGY FOR FEED CULTIVATION AND CREATION OF HAYFIELDS AND PASTURES IN THE FOREST AND STEPPE ZONE OF NORTHERN KAZAKHSTAN

A high-quality feed base is a must to ensure the growing of numerous animals via selecting promising high-yielding crops that can provide livestock with feeds at the entire production stage. This study purposed to develop new technologies for reinstating a balanced use of pastures in Kazakhstan’s steppe and forest-steppe zones. Several investigations succeeded in 2019–2022 at the Service-ZHARS Limited Liability Partnership (LLP) production fields of District Kyzylzhar, North Kazakhstan. Five chosen pasture combinations created multifactor pasture lands, as follows: common alfalfa + Festulolium; awnless brome + yellow sweet clover; common alfalfa + pasture ryegrass + Festulolium; white sweet clover + awnless brome + Timothy grass, and sainfoin + Festulolium + pasture ryegrass + Timothy grass. For haymaking and pasture chain construction, the following grass combinations selected comprised two-pasture grasses (previous years' brome and Timothy grass + common alfalfa + sainfoin) and seven hay grasses (vetch + oats, Sudan grass, sorghum-Sudan grass hybrid + sorghum, corn for silage, sorghum, peas + oats + barley + wheat, and peas). The use of droughtresistant legumes, cereals, and arable crops and their mixtures positively impacted intensifying the feed base and reducing the pasture areas’ degradation. Thus, in the first experiment, the green mass collection was higher than 3.33 t ha-1 , while in the second one, it was below 4.75 t ha-1 , which fully bestowed the physiological needs of animals. The species diversity of pasture vegetation has improved because of beans’ inclusion, possibly enhancing the protein ratio in green feed and hay as the main component of the farm animals' diet.

Dose response to postruminal urea in lactating dairy cattle

Inclusion of urea in dairy cattle diets is often limited by negative effects of high levels of feed urea on dry matter intake (DMI) and efficiency of rumen N utilization. We hypothesized that supplying urea postruminally would mitigate these limitations and allow greater inclusion of urea in dairy cattle diets. Four rumen-fistulated Holstein-Friesian dairy cows (7 ± 2.1 lactations, 110 ± 30.8 d in milk; mean ± standard deviation) were randomly assigned to a 4 × 4 Latin square design to examine DMI, milk production and composition, digestibility, rumen fermentation, N balance, and plasma constituents in response to 4 levels of urea continuously infused into the abomasum (0, 163, 325, and 488 g/d). Urea doses were targeted to linearly increase the crude protein (CP) content of total DMI (diet plus infusion) by 0%, 2%, 4%, and 6% and equated to 0%, 0.7%, 1.4%, and 2.1% of expected DMI, respectively. Each 28-d infusion period consisted of a 7-d dose step-up period, 14 d of adaptation, and a 7-d measurement period. The diet was fed ad libitum as a total mixed ration [10.9% CP, 42.5% corn silage, 3.5% grass hay, 3.5% wheat straw, and 50.5% concentrate (dry matter basis)] and was formulated to meet 100%, 82%, and 53% of net energy, metabolizable protein, and rumen-degradable protein requirements, respectively. Linear, quadratic, and cubic effects of urea dose were assessed using polynomial regression assuming the fixed effect of treatment and random effects of period and cow. Dry matter intake and energy-corrected milk yield responded quadratically to urea dose, and milk urea content increased linearly with increasing urea dose. Apparent total-tract digestibility of CP increased linearly with increasing urea dose and ruminal NH3-N concentration responded quadratically to urea dose. Mean total VFA concentration was not affected by urea dose. The proportion of N intake excreted in feces decreased linearly and that excreted in urine increased linearly in response to increasing urea dose. The proportion of N intake excreted in milk increased linearly with increasing urea dose. Urinary urea excretion increased linearly with increasing urea dose. Microbial N flow responded cubically to urea dose, but the efficiency of microbial protein synthesis was not affected. Plasma urea concentration increased linearly with increasing urea dose. Regression analysis estimated that when supplemented on top of a low-CP diet, 179 g/d of postruminal urea would maximize DMI at 23.4 kg/d, corresponding to a dietary urea inclusion level of 0.8% of DMI, which is in line with the current recommendations for urea inclusion in dairy cattle diets. Overall, these results indicate that postruminal delivery of urea does not mitigate DMI depression as urea dose increases.