Sudan grass and sorghum-sudangrass hybrids are used by ruminants as pasture, fresh forage, hay, silage and baleage. They are valuable warm-season annual forages in systems where summer growth of cool-season pastures is limited, or where a drought-tolerant forage is required. However, results obtained with sorghum-sudangrass hybrids should not be presented as applying automatically to Sudan grass sensu stricto, as many recent cultivars are agronomic hybrids between forage sorghum and Sudan grass. In all cases, grazing and harvesting management must account for the risks of hydrocyanic acid and nitrate accumulation, especially in young regrowth, drought-stressed forage, heavily fertilised crops and forage affected by frost (Hacker, 1992; Simili et al., 2013; Lauriault et al., 2021; Shehab et al., 2020).
The feeding value of Sudan grass-type forages depends strongly on cultivar, brown midrib (BMR) status, stage of maturity, conservation method and associated species. Advancing maturity generally increases dry matter and fibre concentration and decreases crude protein and calculated energy values, while BMR traits tend to improve fibre degradability and energy value, particularly when forage is harvested later than the vegetative stage (Beck et al., 2013; Silva et al., 2018). Legume associations can improve crude protein supply and degradability, but their value depends on successful establishment and on maintaining acceptable silage fermentation (Demirel et al., 2003; Stojanovi̇ć et al., 2020).
Cattle
Fresh forage and grazing
Sudan grass pasture can support cattle production, but animal performance is closely related to forage maturity and pasture structure. In Mississippi, stocker calves grazing three sudangrass cultivars had good gains during the first part of the summer grazing season, but gains declined as the crop matured, in parallel with lower digestibility and crude protein and higher fibre concentrations (Parish et al., 2013). In Brazil, cull cows grazing Sudan grass had grazing, rumination and displacement patterns broadly comparable to cows grazing pearl millet, though behaviour changed as the pasture matured and the leaf:stem ratio declined (Pacheco et al., 2013).
Sudan grass-type forages can also be used in mixed or intercropped summer grazing systems. In Wisconsin, BMR sudangrass intercropped with Kura clover had lower nutritive value than corn intercropped with Kura clover, but produced more harvested forage and greater steer gain per hectare because of its regrowth capacity after grazing (Nieman et al., 2020). In Kentucky, increasing the complexity of summer annual mixtures did not necessarily improve forage yield, nutritive value or beef-calf performance, largely because complex mixtures were dominated by grasses and legumes established poorly (Mercier, 2021).
Sorghum-sudangrass hybrids are often used to fill summer forage gaps in beef and dairy grazing systems. In organic dairy grazing systems in Minnesota, adding warm-season annual pastures including BMR sorghum-sudangrass increased summer forage yield while maintaining NDF digestibility similar to that of cool-season pastures, although crude protein was lower (Ritz et al., 2020). In a Canadian organic grass-fed system, sorghum-sudangrass produced high mid-summer biomass, but low crude protein and drought-related prussic-acid risk limited its practical grazing value (Van Die et al., 2022).
In semi-arid or frost-prone systems, the usefulness of sorghum-sudangrass hybrids depends on safety management. In New Mexico, sorghum-sudangrass and pearl millet had similar forage yields, but pearl millet extended autumn grazing because sorghum-sudangrass had to be withdrawn after frost owing to hydrocyanic acid risk (Lauriault et al., 2021). Conversely, a prussic-acid-free sorghum-sudangrass hybrid gave higher cattle gains than pearl millet under irrigated semi-arid conditions, with nitrate and prussic-acid concentrations below the stated toxicity thresholds (Aviles et al., 2026). These contrasting results indicate that non-cyanogenic cultivars may improve grazing flexibility, but they do not remove the need to monitor nitrate risk and forage maturity.
Swath grazing can be used as a low-input winter feeding strategy with sorghum-sudangrass hybrids, but individual liveweight gain may be modest. In Nebraska, allocating swathed sorghum-sudangrass twice weekly rather than once weekly increased carrying capacity but did not affect average daily gain or forage utilisation in growing steers (Aquino et al., 2024).
Hay, silage and baleage
Sudan grass and sorghum-sudangrass hybrids can be conserved as hay, silage or baleage, but their value depends on harvest stage, moisture and feed-out losses. Sudan grass hay has traditionally been used as a roughage source in high-concentrate beef diets. In feedlot steers fed steam-flaked maize-based finishing diets, reducing sudangrass hay from 16 to 8% of diet dry matter improved growth rate and feed efficiency, while coarser grinding did not improve growth performance, although some digestibility measurements were slightly increased (Calderon-Cortes et al., 1996). This suggests that sudangrass hay can provide effective roughage in finishing diets, but excessive inclusion may depress diet energy value.
Sudan grass hay can also be a conserved forage option in tropical systems. In Brazil, chopped sudangrass hay had intermediate hay yield compared with other tropical grasses and had one of the highest crude protein concentrations and the highest estimated total digestible nutrients among the hays evaluated (Aguiar et al., 2006b). In India, a fresh mixture of ricebean and sorghum-sudan fodder fed ad libitum supported moderate growth and positive nitrogen balance in crossbred calves, but dry matter intake and digestible crude protein and total digestible nutrient intakes were insufficient for higher target gains (Singh et al., 2000). In Mexicali, Mexico, in feedlot finishing diets based on steam-flaked maize, Sudan grass hay acted as a roughage source, but increasing its inclusion from 8 to 16% of diet dry matter depressed performance (Calderon-Cortes et al., 1996).
Silage and baleage are useful conservation forms, particularly where haymaking is difficult, but high moisture can impair fermentation. In China, wilting Sudan grass before ensiling, particularly with molasses and Lactobacillus plantarum, improved fermentation quality and in vitro ruminal fermentation characteristics (Wan et al., 2021). In South Korea, inoculation of high-moisture sorghum-sudangrass silage improved fermentation quality, aerobic stability and in vitro dry matter digestibility (Paradhipta et al., 2019). These studies support wilting and suitable inoculation when Sudan grass-type forages are ensiled at high moisture.
In beef cow-calf systems, sorghum-sudangrass baleage can maintain performance but may be penalised by wastage and cost. In Alabama, sorghum-sudangrass baleage supported cow body weight, body condition, milk production and calf gain similarly to pearl millet baleage and bermudagrass hay, but baleage waste and production costs were higher than for bermudagrass hay under the conditions of the trial (Panhans et al., 2020).
Dairy cattle
Sorghum-sudangrass silage can be useful in dairy heifer programmes because its high fibre and moderate energy concentration can help control excess energy intake. In Holstein heifers, sorghum-sudangrass silage-based diets reduced DM, CP and energy intakes compared with a control diet and kept average daily gain within the target range for replacement heifers (Li et al., 2019). This use differs from high-producing lactating cow diets, where large replacement of maize and lucerne silages by sudangrass silage may reduce intake and milk output.
In a US lactating dairy cow trial reported as a conference abstract, increasing inclusion of BMR sudangrass silage from 0 to 30% of diet DM linearly reduced DM intake, milk yield, component yields and energy-corrected milk, while feed efficiency was not affected (Kalscheur et al., 2016). This suggests that even BMR sudangrass silage should be introduced cautiously in diets for high-producing dairy cows and balanced for energy and protein supply.
Where BMR sudangrass was the main forage in balanced dairy cow diets, the method of conservation affected dairy product quality more than milk yield. In Italy, BMR sudangrass fed as hay or silage resulted in similar milk yield and milk fat, but the hay and silage diets led to differences in volatile compounds and sensory properties of Caciocavallo cheese; hay cheese also tended to be preferred by consumers at longer ripening time (Serrapica et al., 2020).
In vitro evidence supports the use of BMR sorghum-sudangrass as a pasture component for dairy systems. In continuous culture, BMR sorghum-sudangrass fermented broadly similarly to cool-season grass-legume pasture, with no evident adverse effect on total volatile fatty acids or microbial nitrogen variables (Ruh et al., 2018). This type of result should be treated as supportive rather than as a substitute for animal performance trials.
Sheep
Sudan grass and sorghum-sudangrass hybrids can be used for sheep as pasture or silage, but the available evidence is uneven and often based on in vitro or degradability studies rather than long-term performance trials. In Italy, late-lactation Sarda ewes grazing sorghum-sudangrass under Mediterranean summer conditions produced slightly more milk than ewes grazing teff, although teff pasture had higher CP and lower ADF and lignin. The authors considered both crops suitable summer forages, with the usual caution that sorghum-sudangrass requires management of cyanogenic risk (Primi et al., 2025).
Recent feeding evidence with sheep supports the partial replacement of maize silage by sorghum-sudangrass silage. In a Chinese trial with Hu sheep, replacing half of the whole-plant maize silage component with sorghum-sudangrass silage improved growth, rumen fermentation and microbial profile, while full replacement did not depress growth (Li et al., 2025).
Legume-sudangrass silages may improve the protein value of Sudan grass-based conserved forages. In Türkiye, adding Hungarian vetch to sudangrass silage improved rumen degradability of dry matter and crude protein in a nylon-bag study, and the authors suggested 25-50% vetch inclusion for mixed silage (Demirel et al., 2003). In Serbia, Sudan grass had lower rumen-degradable protein than lucerne, and ensiling Sudan grass with lucerne or red clover reduced protein degradability compared with pure legume silages, suggesting a possible role for Sudan grass in improving nitrogen-use efficiency in legume-based diets (Stojanovi̇ć et al., 2020).
BMR sorghum-sudangrass hybrids may have higher ruminal fibre degradability than conventional hybrids. In Brazil, BMR sorghum-sudangrass hybrids harvested for cutting or grazing had higher dry matter and NDF disappearance after ruminal incubation in sheep, and higher effective fibre degradability at different passage rates, than conventional hybrids (Silva et al., 2018).
A Turkish year-round pasture study including sorghum-sudangrass as a summer pasture component for Karacabey Merino ewes and lambs found differences in haematological traits among pasture types and production systems. The authors advised monitoring animal health indicators and providing appropriate mineral and vitamin supplementation when needed, but the study does not provide enough evidence to rank sorghum-sudangrass against other summer forages on performance grounds (Tölü et al., 2025).
Goats
Specific recent goat feeding trials with Sudan grass or sorghum-sudangrass hybrids were not identified in the selected literature. Practical use in goats should therefore follow the same principles as for other ruminants: Sudan grass may be offered as pasture, fresh forage, hay or silage, but it should not be grazed or fed when immature, drought-stressed, frost-damaged or suspected of high nitrate or hydrocyanic acid concentration. Conserved forage should be well cured or well fermented, and diets should be balanced for protein, energy and minerals.
