Replacing conventional concentrates with sprouted barley or wheat: Effects on lactational performance, nutrient digestibility, and milk fatty acid profile in dairy cows

Finite natural resources, rising human population, and climate change pose challenges to traditional crop production. Hydroponically grown fodder (i.e., sprouted grains) can be an alternative feed source for dairy cows; however, only sprouted barley has been investigated in low-producing cows. We aimed to evaluate the effect of replacing conventional concentrates with sprouted barley or wheat, grown using hydroponics, on milk production, nutrient digestibility, and milk fatty acid profile in high-producing cows. Twenty-four multiparous Holstein cows (3.25 ± 1.33 lactations; 102 ± 23 DIM; 49 ± 4 kg/d of milk) were used in a replicated 3 × 3 Latin square design with 21-d experimental periods. Following a 2-wk covariate period, cows were fed 1 of 3 experimental diets: a TMR (1) without sprouted grains (control), or with (2) 10% sprouted barley, or (3) 10% sprouted wheat on a DM basis. Experimental diets were formulated to be isoenergetic and isonitrogenous with sprouted grains that replaced ground corn, soybean meal, canola meal, and dextrose. Sprouted grains were grown using a semi-automatic hydroponic system and harvested after 6 d of growth. Data and sample collection occurred during the last 3 d of the covariate and experimental periods. Wide ranges were observed for the DM percent of sprouted grains (12.1%-22.9% and 13.3%-25.7% for barley and wheat, respectively) and the ratio of sprouted fodder to seed (0.67-1.07 for both barley and wheat). Feeding sprouted grains did not modify the yield of milk or ECM; however, DMI were lower for barley, relative to control. Feed efficiencies were greater for barley than for control (1.49 ± 0.03 vs. 1.43 ± 0.03 for milk yield/DMI; 1.85 ± 0.03 vs. 1.73 ± 0.04 for ECM/DMI). Yields and concentrations of milk components (i.e., fat, true protein, and lactose) were not affected by treatment. Milk urea N concentrations were greater for wheat, relative to control or barley. Body weight (752 ± 3 vs. 742 ± 3 kg) and BW gains (6.53 ± 2.99 vs. -9.33 ± 2.91 kg/21 d) were higher for wheat than for control. Apparent total-tract digestibility of organic matter was greater for wheat relative to barley. Digestibilities of NDF and starch were higher for wheat and control, relative to barley, and CP digestibility was greater for wheat, relative to barley and control. Rumination and physical activity were not affected by treatment. In summary, replacing traditional concentrates with sprouted grains grown using hydroponics improved milk production efficiency (barley sprouts) or enhanced body weight gain (wheat sprouts). A life-cycle assessment needs to be conducted to determine the net effect of this feeding strategy for the dairy industry.

Replacing maize silage with hydroponic barley forage in lactating water buffalo diet: impact on milk yield and composition, water and energy footprint, and economics

This study investigated the feasibility of integrating hydroponic barley forage (HBF) production into dairy ruminant production, focusing on its effect on milk yield and components, energy and water footprints, and economic implications. Maize silage (MS) was used as a benchmark for comparison. The research was conducted on a water buffalo dairy farm equipped with a fully automated hydroponic system producing approximately 6,000 kg/d of HBF as fed (up 1,000 kg/d on DM basis). Thirty-three lactating water buffaloes were assigned to 3 dietary treatments based on the level of MS or HBF in the diet: D0 (100% MS), D50 (50% MS and 50% HBF), and D100 (100% HBF). The feeding trial lasted 5 weeks plus a 2-week adaptation period during which each cow underwent a weighing, BCS scoring, recording of milk yield and components, including somatic cell count and coagulation characteristics. Based on the data obtained from the in vivo study, the water and energy footprints for the production of MS and HBF and buffalo milk, as well as income over feed cost, were evaluated. Complete replacement of MS with HBF resulted in a slight increase in milk yield without significant impact on milk component. The resource footprint analysis showed potential benefits associated with HBF in terms of water consumption. However, the energy footprint assessment showed that the energy ratio of HBF was less than 1 (0.88) compared with 11.89 for MS. This affected the energy efficiency of milk yield in the 3 diets, with the D50 diet showing poorer performance due to similar milk yield compared with D0, but higher energy costs due to the inclusion of HBF. The production cost of HBF was about 4 times higher than that of farm-produced MS, making feed costs for milk yield more expensive. Nevertheless, HBF can potentially improve income over feed costs if it increases milk yield enough to offset its higher production costs. Overall, the results suggest that the current practice of using HBF to replace high quality feedstuffs as concentrates is likely to result in energy and economic losses.

Impact of 5-20% Hydroponic Wheat Sprouts Inclusion on Growth and Metabolic Parameters of Growing Ewes

The aim of this study was to assess the impact of varying proportions (5-20%) of hydroponic wheat sprouts in the diet of growing four-month-old Hu ewes on their productive performance, metabolic profiles, rumen fermentation, and alterations in microflora. Compared with the control group (CON), the optimum final weight of ewes has been presented in the group of substitution 15% (S15) of the basal diet with hydroponic wheat sprouts. Furthermore, 1-30 d the average daily gain (ADG), 31-60 d ADG, and average feed intake were both significantly improved in S15 compared with CON (p < 0.05). Feeding hydroponic wheat sprouts can significantly increase high-density lipoprotein and interleukin-2 (p < 0.05) accompanied by the numerical increase of the content of interferon-γ, suggesting its positive effect on ewes' health and immune systems. In this process, it is noteworthy that feeding hydroponic wheat sprouts results in an increase in relative abundance of Olsenella, Limosilactobacillus, Shuttleworthia, and Prevotella_7, and a decrease in relative abundance of Succinimonas, Pseudobutyrivibrio, and Anaerovibrio in the rumen of growing ewes. It implies that the response of rumen microflora adapted to the change of dietary ingredients, as well as the relationship between rumen microflora changes and the improvement of productive performance and immune system in growing ewes. Considering the usage cost and application effect, S15 of the basal diet with hydroponic wheat sprouts could be the appropriate application solution for growing ewes.

Hydroponic barley supplementation fed with high protein diets improves the production performance of lactating dairy cows

The study investigated the effects of dietary protein level and the inclusion of hydroponic barley sprouts (HB) on lactation performance, blood biochemistry and N use efficiency in mid-lactation dairy cows. Treatments were arranged in a 2 × 2 factorial design with 2 crude protein (CP) levels [16.8% and 15.5% of dry matter (DM)], with HB (4.8% of DM, replacing 4.3% of alfalfa hay and 0.5% of distillers dried grains with solubles (DDGS)) or without HB. Forty-eight multiparous Holstein dairy cows (146 ± 15 d in milk, 40 ± 5 kg/d of milk) were randomly allocated to 1 of 4 diets: high protein diet (16.8% CP, HP), HP with HB (HP+HB), low protein diet (15.5% CP, LP), or LP with HB (LP+HB). An interaction between CP × HB on dry matter intake (DMI) was detected, with DMI being unaffected by HB inclusion in cows fed the high CP diets, but was lower in cows fed HB when the low CP diet was fed. A CP × HB interaction was also observed on milk and milk protein yield, which was higher in cows fed HB with HP, but not LP. Inclusion of HB also tended to reduce milk fat content, and feeding HP resulted in a higher milk protein and milk urea N content, but lower milk lactose content. Feed efficiency was increased by feeding HP or HB diets, whereas N efficiency was higher for cows fed LP or HB diets. There was an interaction on the apparent total-tract digestibility of DM and CP, which was higher when HB was fed along with HP, but reduced when fed with LP, whereas the digestibility of ADF was increased by feeding low protein diets. In conclusion, feeding a low protein diet had no adverse effect on cow performance, while feeding HB improved milk and milk component yield, and N efficiency when fed with a high CP diet, but compromised cow performance with a low CP diet.

Use of reclaimed urban wastewater for the production of hydroponic barley forage: water characteristics, feed quality and effects on health status and production of lactating cows

The safety of reclaimed urban wastewater (RUW) for the production of hydroponic barley forage (HBF) was evaluated in terms of effluent and forage characteristics, as well as the health and performance of lactating cows. The study was conducted on a dairy farm equipped with two hydroponic chambers producing approximately 620 kg/d of HBF as fed. For experimental purposes, HBF was produced using RUW collected from an aqueduct plant processing urban wastewater in a membrane bioreactor treatment chain. A feeding trial was carried out with HBF derived from RUW. Sixty lactating cows were randomly assigned to two balanced groups fed a standard total mixed ration (TMR) or a TMR in which 10 kg of HBF replaced 1 kg of oat hay and 0.5 kg of maize. The experimental period lasted 7 weeks, including a 2-week adaptation period, during which each cow underwent a physical examination, BCS scoring, blood sampling for a complete blood count and biochemical panel, recording of body weight and milk yield and quality, including fatty acid composition and heavy metal content. Ruminal pH was continuously monitored by reticulorumen boluses, and nutrient digestibility and N balance were determined at week 7. RUW showed an acceptable microbial load and an overall good quality as irrigation water, even though the supply of N and P did not influence the yield and quality of HBF. The characteristics of HBF reflected the quality of RUW supplied to the hydroponic chambers and no anomalous components (i.e., high ion concentration) were found. Feeding RW-derived HBF to lactating cows had no major positive or negative effects on animal health and production, including milk quality, ruminal pH, in vivo digestibility, and N balance. The use of RUW under the conditions tested appears to be safe for the health status of lactating cows and the quality of the milk obtained. Overall, the results do not reveal any major limitations for the use of tertiary wastewater as irrigation water for the hydroponic production of forage barley, so that a wider use of wastewater in hydroponic systems seems realistic.

Effects of Feeding Different Levels of Sprouted Barley on Fermentation Characteristics, Bacterial Quantification, and Rumen Morphology of Growing Lambs

The objective of the present study was to investigate the effects of sprouted barley inclusion level on the growth performance, digestibility, volatile fatty acids, bacterial quantification, and rumen morphology of growing lambs. Five dietary treatments with sprouted barley (0, 25, 50, 75 and 100%) and nine replicates per dietary treatment were performed on forty-five Awassi lambs (90 days old). The average weight gain, intake, and digestibility of dry and organic matter were recorded. The pH, color, volatile fatty acids, bacterial quantification, and rumen histomorphometry were also determined. The results showed that the average dry and organic matter intake in T2 to T4 and the average weight gain in T4 decreased linearly. In contrast, the digestibility of dry and organic matter by sprouted barley (T2 to T4) was higher. The pH values and rumen color were not affected. Concentrations of formic acid, acetic acid, butyric acid, and the ratio of acetic acid to propionic acid were increased, while lactic acid and total volatile fatty acids were lower in all levels of sprouted barley. In addition, lambs fed T4 had a higher quantification of Anaerovibrio Lipolytica, Butyrivibrio Fibrisolvens, and Streptococcus Bovis quantification. Selenomonas Ruminantium was higher in T1, T2, and T4, whereas Megashpaera Elsdenii was lower in T1 to T3. The rumen histomorphometric was improved by sprouted barley (T2 and T3). Sprouted barley improved digestibility and rumen histomorphometry and increased the concentration of some volatile fatty acids and rumen bacteria but resulted in a decrease in average dry and organic matter intake, which negatively affected weight gain in lambs fed 100 % sprouted barley. Further studies are required to determine the potential effects on growing lambs fed sprouted barley.

Evaluation of the Nutritive Value and Digestibility of Sprouted Barley as Feed for Growing Lambs: In Vivo and In Vitro Studies

The main objective of this study was to investigate the effects of freshly sprouted barley on the growth of lambs, in addition to its nutritional value and digestibility. In addition, sprouted barley digestibility and rumen fermentation were studied in vitro on a dry matter (DM) basis. A total of 45 three-month-old Awassi lambs were randomly assigned to five treatments of sprouted barley (0, 25, 50, 75, 100%) diets. Bodyweight, weight gain, feed intake and feed efficiency were recorded every two weeks. Nutrient analyses were performed on feed, faecal, and urine samples. DM and non-fibrous carbohydrates were measured. Digestibility of DM, organic matter (OM), and neutral detergent fiber (NDF), as well as gas production, pH value, ammonia-N, and volatile fatty acids (VFAs), were determined in vitro using continuous culture. The results showed that final bodyweight was lower (p < 0.05), while feed intake and the feed-to-gain ratio were increased (p < 0.05) in sprouted barley treatments. Nutrient analysis indicators of sprouted barley treatments (25 to100%) were lower (p < 0.05) for DM, crude protein, acid detergent fiber, lignin and ash, and higher for total digestible nutrients, NDF, fat, phosphorus, zinc, copper, and net energy than the traditional diet. In the in vivo study, the digestibility of nutrients in sprouted barley treatments was improved (p < 0.05), while the diet (sprouted barley 100%) had the lowest digestibility of DM, OM, and NDF compared with the other treatments in the in vitro study. In conclusion, the addition of sprouted barley improved digestibility, and fermentation characteristics, while having a negative effect on growth. Further studies are recommended for optimal growth performance.

Hydroponic fodder and greenhouse gas emissions: a potential avenue for climate mitigation strategy and policy development

This research explores the potential hydroponic systems have for contributing to climate mitigation in fodder agriculture. Using British Columbia (BC) and Alberta as case studies, the study compares greenhouse gas (GHG) emissions and carbon sequestration potential of hydroponically grown sprouted barley fodder to conventional barley grain fodder. GHG emissions were examined through scenarios that assumed Alberta to be the main barley producer, while exploring different situations of BC and Alberta as consumers, distributed/centralized hydroponic systems, and renewable/nonrenewable energy. Carbon sequestration opportunities were examined through scenarios that explored the land sparing potential of transitioning from conventional to hydroponic barley and shifts from tillage to no-tillage practices. Sensitivity analyses were done to examine how changes in hydroponic seed-to-fodder output and energy consumption affect the systems’ climate mitigation potential. The results indicated that incorporating hydroponic systems into barley production has the potential to reduce GHG emissions, given seed-to-fodder output and energy consumption are maintained at certain levels and the systems are powered by renewable energy. Results also showed that hydroponic farming can provide greater carbon sequestration opportunities than simply shifting to no-tillage farming. The research indicates that hydroponic fodder farming could contribute to climate mitigation objectives if complemented with effective energy and land use policies.

Effect of feeding warm-season annuals with orchardgrass on ruminal fermentation and methane output in continuous culture

A 4-unit, dual-flow continuous culture fermentor system was used to assess nutrient digestibility, volatile fatty acids (VFA) production, bacterial protein synthesis, and methane (CH₄) output of warm-season annual grasses. Treatments were randomly assigned to fermentors in a 4 × 4 Latin square design using 7 d for adaptation to treatment and 3 d for sample collection. Treatments were (1) 100% orchardgrass (Dactylis glomerata L.; ORD); (2) 50% orchardgrass + 50% Japanese millet [Echinochloa esculenta (A. Braun) H. Scholz; MIL]; (3) 50% orchardgrass + 50% brown midrib sorghum × sudangrass (Sorghum bicolor L. Moench × S. bicolor var. sudanense; SSG]; or (4) 50% orchardgrass + 25% millet + 25% sorghum × sudangrass (MIX). Fermentors were fed 60 g of dry matter (DM)/d in equal portions of herbage 4 times daily (0730, 1030, 1400, and 1900 h). To replicate a typical 12-h pasture rotation, fermentors were fed the orchardgrass at 0730 and 1030 h and the individual treatment herbage (orchardgrass, Japanese millet, sorghum × sudangrass, or 50:50 Japanese millet and sorghum × sudangrass) at 1400 and 1900 h. Gas samples for CH₄ analysis were collected 6 times daily at 0725, 0900, 1000, 1355, 1530, and 1630 h. Fermentor pH was determined at the time of feeding, and fermentor effluent samples for NH₃-N and VFA analyses were taken daily at 1030 h on d 8, 9, and 10. Samples were also analyzed for DM, organic matter (OM), crude protein, and fiber fractions to determine nutrient digestibilities. Bacterial efficiency was estimated by dividing bacterial N by truly digested OM. True DM and OM digestibilities and pH were not different among treatments. Apparent OM digestibility was greater in ORD than in MIL and SSG. The concentration of propionate was greater in ORD than in SSG and MIX, and that of butyrate was greatest in ORD and MIL. Methane output was greatest in MIL, intermediate in ORD, and lowest in SSG and MIX. Nitrogen intake did not differ across treatments, whereas bacterial N efficiency per kilogram of truly digestible OM was greatest in MIL, intermediate in SSG and MIX, and lowest in ORD. True crude protein digestibility was greater in ORD versus MIL, and ORD had lower total N, non-NH₃-N, bacterial N, and dietary N in effluent flows than MIL. Overall, we detected little difference in true nutrient digestibility; however, SSG and MIX provided the lowest acetate to propionate ratio and lower CH₄ output than MIL and ORD. Thus, improved warm-season annual pastures (i.e., brown midrib sorghum × sudangrass) could provide a reasonable alternative to orchardgrass pastures during the summer months when such perennial cool-season grass species have greatly reduced productivity.

Effect of starchy or fibrous carbohydrate supplementation of orchardgrass on ruminal fermentation and methane output in continuous culture

A 4-unit dual-flow continuous culture fermentor system was used to assess the effects of supplementing orchardgrass (Dactylis glomerata L.) with 2 levels [5 and 10% of total dry matter (DM) fed] of starchy (barley grain, BAR) or fibrous (beet pulp, BP) carbohydrate sources on nutrient digestibility, volatile fatty acid (VFA) production, bacterial protein synthesis, and CH4 output. Treatments were randomly assigned to fermentors in a 4×4 Latin square design with a 2×2 factorial arrangement using 7 d for microbial adaptation and 3 d for sample collection. Treatments included (1) 57g of DM orchardgrass + 3g of DM BAR, (2) 54g of DM orchardgrass + 6g of DM BAR, (3) 57g of DM orchardgrass + 3g of DM BP, or (4) 54g of DM orchardgrass + 6g of DM BP. Feedings occurred at 0900, 1030, 1400, and 1900h throughout four 10-d periods. Gas samples for CH4 analysis were collected 6 times daily at 0725, 0900, 1000, 1355, 1530, and 1630h. Fermentor samples for pH, NH3-N, and VFA analysis were taken on d 8, 9, and 10. Samples were also analyzed for DM, organic matter, crude protein, purines, neutral detergent fiber, and acid detergent fiber to determine nutrient digestibilities and estimation of bacterial protein synthesis. Apparent and true DM and organic matter digestibilities were not affected by supplement source. Apparent neutral and acid detergent fiber digestibilities were greater for BAR than BP. Conversely, apparent crude protein digestibility was greater for BP than BAR. Mean and maximum pH tended to be greatest for BAR than BP. Minimum pH was greater at the lower level (5% of diet DM) of supplementation. Barley produced greater concentrations of total VFA and acetate, whereas BP had greater daily outputs of CH4. Significant supplement type × level interactions were found for bacterial N flow and efficiency. Overall, supplementing orchardgrass with BP improved crude protein digestibility, reduced fiber digestibility and total VFA concentration, but increased CH4 output compared with BAR.