This chapter presents the expected climate scenario in corn-producing areas and suggests alternative strategies for producing resilient forage for dairy cattle in dry continental climate zones. The consideration of irrigating corn for silage production arises due to the alterations in climate. However, it is anticipated that different crop rotations will suffice to sustain the forage supply on intensive dairy farms without requiring additional water resources in the dry season, including drought-resistant crops, early-cut whole-crop cereals, and intense annual ryegrass alongside corn and sorghum. Crop management and crop rotation strategies adapted to local and weather conditions are critical to maintaining milk production. Due to the high digestibility, digestible NDF, and undigestible NDF of the early cut, intensively growing grass silages, rye silage (harvested at the boot stage or earlier), triticale, barley, and wheat silage (harvested at boot-early heading stage) could increase dairy cows’ dry matter intake and milk production under heat-stress conditions. As a result, cattle feed will contain more ingredients than it does today to cope with climate change in cattle feeding.

Near-infrared (NIR) spectroscopy was employed to determine the differences between forage mixtures of winter cereals and Italian ryegrass and to evaluate fermentation characteristics of mixed silages. Forages were harvested on five phases (Cuts 1-5), with 1 week interval (n = 100). The yield of the last harvest (Cut 5) was ensiled and analyzed on four different days (D0, D7, D14, and D90) (n = 80). Principal component analysis based on the NIR data revealed differences according to the days of harvest, differences between winter cereals and Italian ryegrass forages, and differences in the fermentation stages of silages. The partial least square regression models for crude protein (CP), crude fiber (CF), and ash gave excellent determination coefficient in cross-validation (R2 CV  > 0.9), while models for ether extract (EE) and total sugar content were weaker (R2 CV  = 0.87 and 0.74, respectively). The values of root mean square error of cross-validation were 0.59, 0.76, 0.22, 0.31, and 2.36 %DM, for CP, CF, EE, ash, and total sugar, respectively. NIR proved to be an efficient tool in evaluating type and growth differences of the winter cereals and Italian ryegrass forage mixtures and the quality changes that occur during ensiling.

The study was conducted with the objective of evaluating the nutrient content, fermentation characteristics, microbial counts, and ruminal degradability of two mixtures of Italian ryegrass (Lolium multiflorum Lam.) and winter cereal silages. Two mixtures (mixture A: Italian ryegrass, triticale, oats, wheat and barley; and mixture B: Italian ryegrass and oats) were wilted and ensiled in laboratory‐scale silos without additives. At the end of 90 d fermentation mixture B silage had higher (p < .05) dry matter (DM), ether extract (EE), crude fibre (CF), neutral detergent fibre (NDF) and acid detergent fibre (ADF) contents than mixture A silage. The pH value of mixture B was higher (p < .05) than mixture A silage. Mixture A had higher lactate, acetate and ethanol contents than mixture B. However, mixture B had higher NH3-N (day 14) than mixture A silage. The mould and yeast count (Log10 CFU g−1) was higher (p < .05) for mixture A than mixture B at opening day 7. The in situ incubation revealed that potentially degradable fraction (b) of DM, CP and NDF was 39.41%, 43.59%, 80.23% (mixture A) and 39.16%, 32.39%, 94.35% (mixture B). The effective protein degradability (EPD) at 0.08 rumen outflow rates was 67.26% (mixture A) and 67.19% (mixture B). These results suggest that with the proper stage of harvesting, Italian ryegrass and winter cereal mixtures were fermented well. This kind of mixtures can be ensiled without additives in the future. The high potentially degradable NDF and effective protein degradability implies that this mixture could be included successfully in high-yielding dairy cattle diets.Highlights Italian ryegrass and winter cereal mixtures are well preserved without additives and it saves the cost of additives for dairy farmers. The ensiled mixtures have high potentially degradable NDF and effective protein degradability, which improve dry matter intake, milk production and increase the net return of farm. The mixture forage can be double-cropped with corn for silage making, which can have both environmental and economic benefits if the ensiled mixture yields are enough to cover expenses.

During silage making microbial fermentation produces an array of end products which can influence the odour of the final silage and can also change many nutritive aspects of a forage. The objective of this study was to evaluate the fermentation quality and aroma profile of winter cereals and Italian ryegrass (Lolium multiflorum Lam., IRG) plus winter cereal mixture silages detected with an electronic nose. Four mixtures (mixture A: triticale, oats, barley and wheat; mixture B: triticale, barley and wheat; mixture C: IRG and oats; mixture D: IRG, oats, triticale, barley and wheat) were harvested, wilted and ensiled in laboratory-scale silos (n = 80) without additives. Mixture C had higher (P < 0.05) mold and yeast (Log10 CFU (colony forming unit)/g) counts compared to mixture B. Mixture B and C had higher acetic acid (AA) content than mixture A and D. The lactic acid (LA) content was higher for mixture B than mixture C. At the end of 90 days fermentation winter cereal mixture silages (mixture A and B) had similar aroma pattern, and mixture C was also similar to winter cereal silages. However, mixture D had different aromatic pattern than other ensiled mixtures. Both the principal component analysis (PCA) score plot for aroma profile and linear discriminant analysis (LDA) classification revealed that mixture D had different aroma profile than other mixture silages. The difference was caused by the presence of high ethanol and LA in mixture D. Ethyl esters such as ethyl 3-methyl pentanoate, 2-methylpropanal, ethyl acetate, isoamyl acetate and ethyl-3-methylthiopropanoate were found at different retention indices in mixture D silage. The low LA and higher mold and yeast count in mixture C silage caused off odour due to the presence of 3-methylbutanoic acid, a simple alcohol with unpleasant camphor-like odor. In general, the electronic nose (EN) results revealed that the ensiled mixtures were dominated by ethyl ester likely producing pleasant fruity odors which could increase the intake of ensiled mixtures. However, the technology is suitable in finding off odor compounds of ensiled forages that may likely reduce feed intake.

This study was conducted using three multiparous non-lactating rumen-cannulated Holstein-Friesian dairy cows, with the objective of evaluating the in situ ruminal degradability and fermentation characteristics of novel mixtures of winter cereal and Italian ryegrass (Lolium multiflorum Lam.) plus winter cereal silages (mixture A: triticale, oats, barley and wheat; mixture B: triticale, barley and wheat; mixture C: Italian ryegrass and oats; mixture D: Italian ryegrass, oats, triticale, barley and wheat).The rumen fermentation study was conducted replacing the ensiled mixtures (experimental diets) with vetch-triticale haylage in a total mixed ration (control diet).It was found that the effective protein degradability at 0.08 rumen outflow rates was 80.6% (mixture A), 66.2% (mixture B), 79.7% (mixture C) and 79.3% (mixture D).The effective neutral detergent fibre (NDF) and acid detergent fibre (ADF) effective degradability at 0.08 rumen outflow rates was 18.0% and 17.7% (mixture A), 19.7% and 20.5% (mixture B), 19.1% and 17.0% (mixture C), and 15.2% and 14.6% (mixture D), respectively.Different dietary treatments did not change (P > 0.05) the rumen fermentation characteristics as there was no difference (P > 0.05) between control and experimental diets, and the inclusion of 40-55% Italian ryegrass (mixture C and D) did not cause any difference.These results suggest that the mixture of winter cereals and Italian ryegrass plus winter cereal-based silages had good potentially degradable dry matter, effective dry matter and effective protein degradability at 0.01, 0.05 and 0.08 rumen outflow rates without affecting the rumen environment maintaining neutral pH.The ensiled mixtures had a moderate level of potentially degradable NDF and ADF fraction.

The objective of this study was to evaluate the aroma profile, microbial and chemical quality of winter cereals (triticale, oats, barley and wheat) and Italian ryegrass (Lolium multiflorum Lam., IRG) plus winter cereal mixture silages detected with an electronic nose. Four commercial mixtures (mixture A (40% of two cultivars of winter triticale + 30% of two cultivars of winter oats + 20% of winter barley + 10% of winter wheat), mixture B (50% of two cultivars of winter triticale + 40% of winter barley + 10% of winter wheat), mixture C (55% of three types of Italian ryegrass + 45% of two cultivars of winter oat), mixture D (40% of three types of Italian ryegrass + 30% of two cultivars of winter oat + 15% of two cultivars of winter triticale + 10% of winter barley + 5% of winter wheat)) were harvested, wilted and ensiled in laboratory-scale silos (n = 80) without additives. Both the principal component analysis (PCA) score plot for aroma profile and linear discriminant analysis (LDA) classification revealed that mixture D had different aroma profile than other mixture silages. The difference was caused by the presence of high ethanol and LA in mixture D. Ethyl esters such as ethyl 3-methyl pentanoate, 2-methylpropanal, ethyl acetate, isoamyl acetate and ethyl-3-methylthiopropanoate were found at different retention indices in mixture D silage. The low LA and higher mold and yeast count in mixture C silage caused off odour due to the presence of 3-methylbutanoic acid, a simple alcohol with unpleasant camphor-like odor. At the end of 90 days fermentation winter cereal mixture silages (mixture A and B) had similar aroma pattern, and mixture C was also similar to winter cereal silages. However, mixture D had different aromatic pattern than other ensiled mixtures. Mixture C had higher (p < 0.05) mold and yeast (Log10 CFU (colony forming unit)/g) counts compared to mixture B. Mixture B and C had higher acetic acid (AA) content than mixture A and D. The lactic acid (LA) content was higher for mixture B than mixture C. In general, the electronic nose (EN) results revealed that the Italian ryegrass and winter cereal mixtures (mixture D) had better aroma profile as compared to winter cereal mixtures (mixture A and B). However, the cereal mixtures (mixture A and B) had better aroma quality than mixture C silage. Otherwise, the EN technology is suitable in finding off odor compounds of ensiled forages.

The interest in new alternative forages in Europe has increased in recent years. The nutritional composition and fermentation characteristics during different stages of ensiling were studied with Italian ryegrass (Lolium multiflorum Lam.) and winter cereal mixtures. The trial was carried out on a large-scale farm Galgamenti Agricultural Limited Company, Tura, Hungary. Two different forage mixes were studied: Mixture A (three types of Italian ryegrass 40% + two types of triticale 20%+ two types of oats 20%+ wheat 15%+ barley 5%) and Mixture B (three types of Italian ryegrass 55% + two types of winter oats 45%). Experimental field was 30.600 m 2 by the treatments, respectively. The two different forage mixes were sown on 11th September 2017 (Mixture A: 75 kg seed/ha; Mixture B: 75 kg seed/ha) with depth of 2-5 cm. Plant protection treatment was not applied during the growing season. Cutting was carried out in heading stage of triticale by hand at 10 cm stubble height. The fresh Mixture A (dry matter 189 g/kg; crude protein: 161 g/kg DM; NDF: 485 g/kg DM) and the fresh Mixture B (dry matter 195 g/kg; crude protein: 159 g/kg DM; NDF: 519 g/kg DM) were wilted to 28-32% DM (24h) without any movement on the windrow. The wilted forage was picked up by hand and chopped by a forage harvester (John Deere 7300) on concrete surface with theoretical chop length of 9 mm (weight: 800 kg). Wilted and chopped material of 510 g were packed by hand into a glass jars (0.00072 m3 volume, n=5, total no. of minisilos = 15). Five laboratory silos per mixtures were opened on 7, 14 and 90 days after ensiling. Dry matter (DM), crude protein (CP), crude fiber (CF), neutral detergent fiber (NDF), acid detergent fiber (ADF), acid detergent lignin (ADL), ether extract (EE), ash, and total sugar of all treatments were determined. Additionally, pH and the concentration of ammonia-N, volatile fatty acids were measured in the ensiled mixtures. At the end of 90 days of ensiling in both mixture silages, there were significant differences (p<0.05) in all nutrient contents except for ADF in Mixture A and CP, ash and CF in Mixture B which was not affected by fermentation duration. Ensiling caused a significant decrease in pH (p<0.05), due to the production of lactic acid and succeeded to achieve lactic acid type fermentation. Values for ammonia-N, ethanol and acetic acid, butyric acid were all low. These results indicated that the fermentation quality of Italian ryegrass and winter cereal silages underwent rapid fermentation and were well-preserved.

Essential oils (EO), an important group of plant extracts, which are concentrated extracts of aromatic oily liquids from various plant materials obtained by steam distillation. Plant-derived EO is a useful means to improve efficiency of nutrient utilization in ruminants and reduce the impact of their production on the environment. In recent years, more research has been directed toward evaluating the potential of EO to improve performance in dairy cows but according to the results the effect of EO on milk production is not consistent. Therefore, the study evaluated the effects of supplementing a mixture of EO (oregano, thyme, citrus, cinnamon, ginger, curcuma, pepper and an organic carrier) in the diet of lactating Holstein Friesian dairy cows (n=46) in late lactation on the intake, milk yield and composition in a dairy farm experiment. The average DIM at the start of the experiment was 156 days. Experimental treatments consisted of a mixture of EO (2 g cow-1 day-1) inclusion in a total mixed ration. There was a 3-week long preliminary and a 7-week long experimental period in the trial. Milk production was recorded every day. Chemical analyses were made from the morning milked samples once a week. Supplementation of dairy cows with mixture of EO significantly (P<0.05) increased the dry matter intake (control: 26.9±1.49 kg DM day-1 vs. experimental: 27.3±0.95 kg DM day-1) but had no effect on milk production (control: 38.3±4.99 kg vs. experimental: 37.9±4.93 kg) and milk composition (fat, protein, lactose). Results show that an intake of 2 g cow-1 day-1 mixture of EO may increase the feed intake but does not influence milk yield and composition in late lactation.

The objective of this study was to determine the effect of an exogenous rumen-resistant amylase preparation on live weight, milk production and milk composition in Holstein Friesian dairy cows (n = 70) in a dairy farm experiment. According to the Hungarian feeding practice corn silage-alfalfa haylage-dried corn meal based diet was used in the diets. Milk production was recorded every day. Chemical analyses were made from the morning milked samples once a week. There was a 3-week long preliminary and a 12-week long experimental period in the trial. Cows used in the experiment were in the 71st (control) and 72nd (experimental) day of lactation. All the animals were weighed at the beginning (control: 651 kg/cow; experimental: 657 kg/cow) and at the end of the trial (control: 685 kg/cow; experimental: 697 kg/cow). The exogenous rumen-resistant α-amylase used in this trial significantly (p < 0.05) improved milk production (control: 37.7 ± 6.96 kg vs. experimental: 38.7 ± 6.97 kg) and significantly (p < 0.001) decreased lactose content of milk (4.60 % vs. 4.55 %). The exogenous rumen-resistant α-amylase had no influence on the fatty acid composition of milk fat.

Summary Th e objective of the present study was to investigate the eff ect of an essential oil product on growth performance and cellular immune response of 28-day-old weaned piglets. A total of 348 piglets (50% gilts, 50% barrows) were assigned to three dietary treatments (6 pens/trt). Th e basal diet was a commercial feed that was supplemented without any growth promoter (NC), with antibiotic growth promoter of 40 ppm avilamycin (PC), or with 0.25 g of an essential oil product (EO) per kg of feed. All pigs were immunized by inactivated Aujeszky’s disease virus vaccine at week one and three of the experiment (28- and 44-days-age, respectively). Blood samples were taken four times (on day one, 16, 24, 32 of the experiment) for lymphocyte stimulation (LST) tests with ConA, PWM, PHA used as non-specifi c and Aujeszky virus used as specifi c mitogens from 2 pigs/pen. All piglets were individually weighed on day 0, 8, 16, 24 and 32 of the trial. Th ere was no signifi cant diff erence among average daily gain, feed intake and feed conversion ratio of piglets fed diff erent dietary treatments. Th e non-specifi c LST test at the 4th blood sampling showed higher values in pigs received feeds with essential oil supplementation (EO) than that of the positive (PC) and negative control (NC) groups (P<0.05). However, no signifi cant diff erence in specifi c immune response of pigs in diff erent dietary treatments was found. It can be concluded that essential oil supplementation may enhance the non-specifi c immunocompetence of 28-day-old weaning pigs without compromising their growth performance.

The fermentation properties of the following feeds: pelleted barley (PB), toasted and pelleted barley (TPB), pelleted maize (PM) and toasted and pelleted maize (TPM) were studied using an in vitro gas production (GP) technique. Each feed sample (0.5g) was incubated (3 replications), with rumen fluid collected from 3 grazing lactating dairy cows. The kinetics of GP were automatically recorded for 72h. The amounts of DM disappeared (DMd) and the volatile fatty acid yields (VFA) were measured. On barley, compared to simple pelleting, toasting significantly (P<0.05) reduced DMd (87.5 vs. 86.2%), the asymptotic GP (A, 388 vs. 367ml/g DMd) and slightly increased the time of maximum GP rate (T(Rmax), 2.89 vs. 3.15h). On maize toasting did not affect DMd and A, but significantly reduced T(1/2) (9.71 vs. 8.57; P<0.05) and T(Rmax) (5.04 vs. 4.49, P<0.05). Toasting significantly reduced the VFA yields both of barley and maize. These results, in agreement with previous in sacco and in vivo observations, suggest that toasting might reduce the amount of potential fermentable substrate of barley, whereas it might increase the rate of fermentation of maize.

Three rumen-cannulated, lactating Holstein-Friesian cows grazed in a controlled experimental pasture and supplemented daily with concentrates were used to measure effects of different heat treatment of cereal grains (pelleted barley, toasted barley, pelleted maize, toasted maize) on in situ degradability of protein and starch and to estimate of the possible rumen synchrony after feeding processed cereal grains as a supplement to perennial ryegrass (Lolium perenne). Pressure toasting treatment increased (P < 0.05) the undegradable fraction of DM and OM and tended to reduce (P > 0.05) in situ protein degradability of the cereal grains. Undegraded intake protein increased (P > 0.05) after pressure toasting from 36.4 to 52.5% for barley and from 50.3 to 58.2% for maize, respectively. Undegraded intake starch increased (P > 0.05) from 14.9 to 16.7% after toasting barley and decreased from 36.1 to 31.3% for toasted maize, respectively. Pressure toasting reduced washable fractions of each cereal grains for both constituents. The fractional rate of degradation of starch increased in maize, but decreased in barley. From the calculated synhrony index which describes the synchrony of nitrogen and organic matter degradation in the rumen it appears that supplementing grass with processed cereal grains can alter microbial growth and efficiency of utilization of nutrients and results in a more synchronous substrate for the microbes.

Three rumen-cannulated, lactating Holstein-Friesian cows grazed in a controlled experimental pasture and supplemented daily with concentrates were used to measure effects of different heat treatment of cereal grains (pelleted barley, toasted barley, pelleted maize, toasted maize) on in situ degradability of protein and starch and to estimate of the possible rumen synchrony after feeding processed cereal grains as a supplement to perennial ryegrass (Lolium perenne). Pressure toasting treatment increased (P 0.05) in situ protein degradability of the cereal grains. Undegraded intake protein increased (P > 0.05) after pressure toasting from 36.4 to 52.5% for barley and from 50.3 to 58.2% for maize, respectively. Undegraded intake starch increased (P > 0.05) from 14.9 to 16.7% after toasting barley and decreased from 36.1 to 31.3% for toasted maize, respectively. Pressure toasting reduced washable fractions of each cereal grains for both constituents. The fractional rate of degradation of starch increased in maize, but decreased in barley. From the calculated synhrony index which describes the synchrony of nitrogen and organic matter degradation in the rumen it appears that supplementing grass with processed cereal grains can alter microbial growth and efficiency of utilization of nutrients and results in a more synchronous substrate for the microbes.

The effect of processed cereal grain supplementation on volatile fatty acid (VFA) production rates of grazing, lactating Holstein-Friesian cows were measured in a 5x5 Latin square experiment. The experimental treatments were as follows: control (only grazing, no supplement addition, NS), pelleted barley (PB), pelleted maize (PM), toasted and subsequently pelleted barley (TPB), and toasted and subsequently pelleted maize (TPM) as supplements. An isotope dilution technique using stable isotope of carbon (13C) as an internal marker was employed for the estimation of VFA production. At the beginning of a 3-hour long allowed grazing time, 100 mg of 99% enriched 13C2 Na-acetate were introduced in the rumen and repeated after grazing with 50 mg isotope, after which the cows were starved for 6 hours until evening milking. During grazing disappearance rate (kdis) and production rate (kprod) of acetate, propionate and butyrate were significantly higher (P≤0.05) in supplemented than in NS cows. Moreover the effect of barley grain and pelleting treatment was higher than the effect of maize grain and toasting. During starvation significantly higher (P≤0.05) kdis and kprod of VFAs were observed in PM and TPM treatments. Total VFA production for the experimental period (grazing + starvation) were 49.5, 78.7, 69.9, 88.5, 80.8 mol/day for NS, PB, TPB, PM and TPM, respectively. The higher VFA productions measured in supplemented animals emphasis the extensive digestion that occurs in the rumen after feeding processed grains. In methodological terms, 13C2 Na-acetate labelling appears to be a useful means for examining the VFA acetate production in ruminants.

Five multiparous lactating Holstein-Friesian dairy cows fitted with rumen cannula were allowed to graze perennial ryegrass swards. Next to a control treatment of grazing only, pelleted barley (PB), pelleted maize (PM), toasted and subsequently pelleted barley (TPB), and toasted and subsequently pelleted maize (TPM) were fed as a supplement in two equal portions. Before and after 3 h of grazing the rumen content was evacuated, weighed, sampled and returned to the animals. Then the cows were kept inside the barn and starved for 6 h, after which rumen evacuations were repeated. The estimated clearance rates of starch showed significant differences (P<0.001) between grain types and compared to unsupplemented animals the apparent ruminal clearance of nitrogen was significantly (P<0.001) reduced. Supplementation with processed grains significantly increased (P<0.05) the milk production and significantly (P<0.001) decreased milk fat percentage. It is concluded that supplementing grass with high-energy low protein feeds, such as grains, substantially improves the N utilization and reduces the urea output in milk.

Effects of heat treatment (expanding) on ruminal and intestinal digestibility of starch in barley and maize grains were studied in an extended 4×4 Latin square experiment. Four lactating Danish Holstein Friesian cows fitted with ruminal, duodenal and ileal cannulae were offered grass-clover silage and grass-clover hay based diets supplemented with soybean meal and either untreated barley, expanded barley (105°C), untreated maize or expanded maize (95°C). Ruminal degradation characteristics of starch for untreated and expanded grains were determined in situ using nylon bags with two pore sizes (15 or 36μm). Rate of starch degradation in the rumen was also determined based on series of total rumen evacuations. In vivo digestibility was estimated by sampling duodenal and ileal contents and faeces. Ruminal degradation of starch determined in situ was higher for barley than maize regardless of heat treatment. In situ studies (36μm) showed expanding increased effective maize starch degradability in the rumen from 0.60 to 0.72, mainly due to an increased soluble fraction. Effective barley starch degradability, however, was unchanged at 0.96 as an increase in the soluble fraction was counterbalanced by a decrease in rate of degradation from 0.63 to 0.36h−1 with 36μm nylon bags. In vivo degradation characteristics based on rumen evacuations showed that heat treatment increased fractional rate of degradation of starch for both barley and maize, resulting in a slight increase in the effective degradability of barley starch from 0.81 to 0.85 and an increase in rumen effective degradability of maize starch from 0.71 to 0.78, when rumen starch pools were corrected for rumen starch outflow. In situ studies seemed to overestimate ruminal degradation of rapidly fermentable starch in barley, and underestimate degradation of slowly fermentable starch in maize, although in situ results were highly dependant on assumptions made on digestion and passage of the soluble fraction. Total tract digestibility of barley starch was not affected by heat treatment (0.99), whereas total digestibility of starch in maize increased from 0.84 to 0.96. Apparent rumen digestibility of starch was higher for barley than maize. Duodenal flow of starch in barley was highest 4h post feeding, whereas a much larger peak was found for maize at 10–12h post feeding, which indicates a passage time lag for undegraded maize starch in the rumen, or possibly the abomasum. Fractional rate of passage of starch from the rumen was not constant, indicating that passage of starch does not follow first order kinetics.