Nutritive value of faba bean (Vicia faba L.) as a feedstuff resource in livestock nutrition: A review

Abstract The review evaluates faba bean (Vicia faba L.; FB) seeds relative to their nutritional composition, their content of antinutritional factors, and their impact on animal performance. The literature indicates that FB plant is a cool‐season, annual grain legume that grows the best in cool and humid conditions. Its seeds are rich in protein, energy, and mineral compounds and have particularly high unsaturated fatty acid levels. However, FB seeds also contain various proportions of antinutritional factors (ANFs) that can interfere with nutrient utilization in nonruminants. The various processing methods are efficient in either reducing or inactivating the ANFs of FB seeds, with extrusion treatment offering the most effective method of improving apparent nutrient and energy digestibility of nonruminants. In vivo studies on ruminants, pigs, poultry, and fishes reveal that FB seeds have the potential to be used as a substitute for soybean meal and/or cereal seeds in livestock diets in order to support milk, meat, and/or egg production.

areas with the poorest soil types in which barley and wheat perform poorly (Castanon et al., 1990). However, fine-textured soils and soils with pH levels >7 are considered to provide the ideal soil conditions for cultivating FB (Etemadi et al., 2019;Köpke & Nemecek, 2010).
Additionally, FB plants stand out for their N fixation efficiency, which is the highest among the cool-season legumes (Álvarez-Iglesias et al., 2018;Olson & Bowness, 2016), and can facilitate the reduction in the use of commercial N fertilizers, providing ecosystem services that contribute to sustainable agriculture .
Although FB seeds play an important role as a source of nutrition in human diets (Etemadi et al., 2018), they also provide the livestock industry with an alternative protein and energy feedstuff source to offset feed costs and ensure a stable feed supply for livestock (Etemadi et al., 2019;Smith et al., 2013). This review elucidates the nutrient profile of FB seeds and their use in animal diets to promote their use in livestock diets.
as the major carbohydrate components (Khan et al., 2015;Morales et al., 2008). In addition, FB seeds are also good sources of dietary minerals (Cazzato et al., 2014), notably potassium, phosphorus, iron, and zinc, while iron and zinc are essential for the sustenance and optimal physiological function of both humans and livestock (Bailey et al., 2015). The gross energy and metabolizable energy (ME) contents of FB seeds, which range from 14.69 to 19.70 MJ/kg DM and from 11.30 to 13.80 MJ/kg DM, respectively. The chemical composition content of FB seeds is highly dependent on the genotypes/cultivars and environmental conditions, as well as agricultural management practices (Ivarsson & Neil, 2018;Micek et al., 2015;Pelagalli et al., 2020;Skylas et al., 2019). Compared with general grains such as rice, corn and wheat, FB seeds contain higher CP, dietary fiber, potassium, iron, and folic acid contents (Howard et al., 2018;Gu et al., 2020).

| Fatty acids and amino acids
The FB seeds contain 38.70 g/kg of total lipids (Akpinar et al., 2001).
The major unsaturated fatty acids in FB seeds are the oleic (56.5 g/ kg), palmitoleic (37.3 g/kg), and linoleic (36.4 g/kg) acids, while the palmitic (67.3 g/kg) and stearic (34.9 g/kg) acids constitute the major saturated fatty acid components of FB (Angell et al., 2016). These results indicate that combined with the high CP content, the unsaturated fatty acid level of FB seeds makes them a low-cost, vegetable protein source for both humans and livestock.
The total amino acid (TAA) content of FB seeds ranges from 217.4 to 322.7 g/kg DM (Table 2). Of the amino acids, essential amino acids (EAAs) account for 132.5 g/kg DM (arginine 25.3 g/ kg DM, leucine 20.4 g/kg DM, and lysine 17.9 g/kg DM), with a higher EAA/TAA ratio than soybean [Glycine max (Linn.) Merr.] meal (SBM) (mean EAA)/TAA = 52.0% and 46.0%, respectively) (Angell et al., 2016), thereby indicating that FB seeds contain protein of a higher quality than SBM. For nonessential amino acids (NEAA), FB seeds constitute 125.4 g/kg DM (glutamic acid 47.9 g/kg DM and aspartic acid 30.7 g/kg DM); however, there may be some differences in the sequence and general structure of amino acids (El Fiel et al., 2002). FB seeds, with their higher levels of lysine and arginine, could be mixed with cereals that would supplement some of the EAA compounds that FB lacks, thereby achieving a more balanced and desirable amino acid profile (Kumar et al., 2015;Skylas et al., 2019).
Overall, FB seeds, as relatively complete feed, provide a rich source of protein, carbohydrates, fats, and minerals, with potential for incorporation into animal diets.

| FAC TOR S IMPAIRING THE UTILIZ ATI ON OF FABA B E AN IN LIVE S TO CK FEEDS TU FF
Despite being rich in protein, carbohydrates, fats, and minerals, FB seeds contain a variety of antinutritional factors (ANFs), such as total phenolics, tannins, and trypsin inhibitor activity (TIA) (Table 3) (Ferruzzi et al., 2009;Hejdysz et al., 2016). These ANFs adversely affect the feed palatability as well as the bioavailability of protein and energy, thereby potentially interfering with certain animal performance indicators such as growth and egg production (Barłóg et al., 2019;Kowalczyk et al., 2020;Multari et al., 2015). For raw FB seeds, ANFs constitute 8.50-28.48 g/kg of total phenolics, 3.80-14.50 g/kg of tannins, 1.61-10.11 g/kg of phytic acid, 16.90-24.02 g/kg of verbascose, 7.60-18.70 g/kg of stachyose, 2.00-4.50 g/kg of raffinose, and 0.60-1.50 g/kg of TIA, depending on the genotype/cultivar, environmental conditions, growing season, seed maturity stage, and agronomic practices implemented (Cucci et al., 2019;Ivarsson & Neil, 2018;Kowalczyk et al., 2020;Oomah et al., 2011). The variation in ANFs in FB seeds may limit their use in feed formulations of animal diets.
Relative to other legumes, such as soybeans and peas (Pisum sativum L.), FB seeds contain similar amounts of tannins and polyphenols, but relatively less TIA, genistein, and daidzein content (Berger et al., 1999), which indicates that FB seeds may less impair the nonruminant nutrition status. However, in ruminants, the ANFs in FB seeds and other seed legumes do not have a substantive effect on nutrient absorption in the small intestine of ruminants because TA B L E 2 Amino acid composition (g/kg dry matter) of faba bean seed summarized from several references a Abbreviation: SD, standard deviation. a Supporting literature: (Aguilera et al., 1992;Barłóg et al., 2019;Biesek et al., 2020;Hejdysz et al., 2016;Ivarsson & Neil, 2018;Koivunen et al., 2016). b Number of supporting literature.
the ANFs might be inactivated after 12-24 hr of in vitro incubation with rumen liquor (Holmes et al., 1993). In fact, tannins in the ANFs might even be beneficial in terms of protein absorption in the small intestine, since high tannin levels in the diet can form stable complexes which protect proteins from rumen microbial degradation (Mohamaden et al., 2020). As indicated in the literature, high inclusion rates of raw FB seeds in diets do not negatively affect the growth performance of male lambs (Bonanno et al., 2012;Lanza et al., 1999).

FABA B E AN
The biological evaluation of FB protein is of critical importance not only in terms of reflecting its potential as an animal feed, but also because chemical analyses do not always reflect the bioavailability and utilization of nutrients in animals (Huang et al., 2019).

| In vitro digestibility
A summary of the in vitro digestibility of FB seeds is shown in Table 4. The in vitro organic matter (OM) and CP digestibility of raw FB seeds ranged from 0.725 to 0.914 (Ferruzzi et al., 2009;Ivarsson & Neil, 2018) and from 0.646 to 0.955, respectively (Chandra-Hioe et al., 2016;Ivarsson & Neil, 2018;Khalil & Mansour, 1995). The in vitro DM and neutral detergent fiber (NDF) digestibility of raw FB seeds were 0.735 and 0.518, respectively (Ferruzzi et al., 2009;Ivarsson & Neil, 2018). Overall, FB seeds have a considerable variation in terms of the in vitro digestibility of their nutrients, which largely depends on the cultivar type, the environmental conditions the crops grown in, and the agronomic practices implemented (Abusin et al., 2009;Buckley et al., 1983;Ivarsson & Neil, 2018;Stone et al., 2019).

TA B L E 3
Antinutritional compounds (g/kg, unless otherwise stated) of faba bean seed summarized from several references a & Hosking, 1992). The ruminal DM and CP degradability of raw FB seeds was largely variable, perhaps depending on the cultivar type, environmental conditions, livestock species, basal diet, rumen outflow rate, and ground particle size.
In ram diets containing FB seeds (162 g/kg), the apparent digestibility of DM, OM, and CP was somewhat lower than that of the SBM control diet (156 g/kg; Table 6), while the apparent digestibility of DM, OM, and CP in raw FB diets was similar to that of the SBM control diet (Zagorakis et al., 2015). On the contrary, in cows, the apparent digestibility of DM, OM, CP, NDF, starch, and energy, as well as N retention were generally unaffected by increasing levels of raw FB seeds (Puhakka et al., 2016). In addition, Cherif et al. (2018) reported that similarities in the apparent digestibility of certain dietary components (i.e., DM, OM, CP, NDF, acid detergent fiber [ADF], starch, and energy) between diets of lactating cows that were fed with raw FB seeds (171 g/kg DM) and those fed with an SBM diets (92 g/kg DM). Overall, the apparent DM, OM, and CP digestibility in the raw FB seed diets was higher in wethers than in rams and lactating cows (Cherif et al., 2018;Hadjipanaiotou et al., 1985;Zagorakis et al., 2015).
There are limited availability of data on the effects of FB seeds on ruminal fermentation characteristics ( Table 7). The ruminal ammonia of dairy cows that were fed 171 g/kg DM of raw FB seeds increased significantly by 20.0% compared with that of dairy cows fed that were fed the SBM control diet (92 g/kg DM) (Cherif et al., 2018).
Nevertheless, the pH, total volatile fatty acid (VFA) concentrations, and VFA molar proportions were similar in dairy cows that were fed with various inclusion levels of FB seeds and SBM (Cherif et al., 2018). In another study, increasing dietary inclusion levels of FB seeds in lactating cows did not affect the total VFA content and molar proportions of VFA, while the NH 3 -N content of rumen fluid in lactating cows fed 59 or 117 g/kg DM of raw FB seeds was significantly higher compared with that of the rapeseed meal diet (Lamminen et al., 2019).
Overall, the results indicate that FB seeds have the similar or higher nutritive value when used as a animal feed compared with the SBM and/or other leguminous seeds.

| In vivo digestibility in nonruminants
The effects of FB seeds on the in vivo digestibility of nonruminants are summarized in Table 8. In the juvenile grass carp, increasing the inclusion of raw FB seeds up to 420 g/kg did not impair apparent digestibility coefficients of DM, CP, and ether extract (EE), while a higher inclusion of 560 g/kg adversely affected the apparent digestibility (Gan et al., 2017). In contrast, juvenile belugas fed 100 g/ kg of the FB seed diet produced similar apparent digestibility coefficients for DM, CP, and EE to juvenile belugas fed wheat diets, while including FB seeds at levels higher than 150 g/kg adversely affected the belugas' apparent digestibility (Soltanzadeh et al., 2017).

TA B L E 4
The in vitro nutrient digestibility of the faba bean (FB) seeds summarized from several references unaffected in European seabass fed diets with various inclusion levels of extruded FB seed (Adamidou, Nengas, Alexis, et al., 2009).
Moreover, apparent EE digestibility for raw FB seeds in broiler chickens ranged from 0.812 to 0.932, with high variability among cultivars (Hejdysz et al., 2016).
According to Landry et al. (2016), the apparent ileal digestibility of dietary components in male pigs fed with 629 g/kg of raw FB seeds diets was relatively high, except for NDF and ADF (Table 9).
Moreover, Mariscal-Landín et al. (2002) found that the apparent ileal digestibility of pigs fed raw FB seeds (463 g/kg) was 0.753 for DM, and 0.741 for CP, while it ranged from 0.555 to 0.862 for amino acids. Compared with lupins (Lupinus albus L.) diet (500 g/ kg), the apparent ileal DM and OM digestibility of male broilers fed a raw FB diet (500 g/kg) was markedly higher, while the apparent ileal CP and amino acid digestibility in raw FB diets were similar to or somewhat lower than the lupin diet. In contrast, 6to 32-day-old male broilers fed raw FB seed diets had markedly higher apparent ileal DM and OM digestibility than broilers fed the SBM control diet (170 g/kg), but apparent ileal digestibility of DM, OM, and CP were generally unaffected in broilers fed with FB seed diets with inclusion levels of 80-160 g/kg . Moreover, Hejdysz et al. (2016)

| IMPROVING THE UTILIZ ATI ON EFFI CIEN C Y OF FABA B E AN S EEDS IN LIVE S TO CK FEEDS
In order to maximize the nutritional value and utilization efficiency of FB seeds, it is crucial that ANFs are reduced or inactivated when they are used as ingredients in nonruminant diets (Ferruzzi et al., 2009;Khalil & Mansour, 1995). Pre-processing of FB including dehulling, germination, soaking, and thermal treatments (i.e., cooking, autoclaving, and extrusion) was not only effective in reducing or eliminating ANFs, but also improved the intake and digestibility of nutrients (Avilés-Gaxiola et al., 2018;Ferruzzi et al., 2009;Hejdysz et al., 2016;Masoero et al., 2005).

| Reducing the ANFs content of faba bean seeds
A summary of the effects of processing methods on the ANFs content of FB seeds is shown in Table 10. Soaking method significantly reduced total phenolics of FB seeds by 26.7% compared with raw FB seeds (Lafarga et al., 2019) while phytic acid was generally unaffected by soaking method (Shi et al., 2018). The phytic acid content of FB seeds significantly decreased, after soaking for 4h before cooking at 95°C in water (1:5 seed:water ratio), by 29.5% of that in raw FB seeds (Shi et al., 2018). The total phenolic content of FB seeds deceased, after soaking for 24 hr before boiling in water (1:10 seed:water ratio), by 29.2% of that determined in raw FB seeds (Lafarga et al., 2019). Khalil and Mansour (1995) also reported that phytic acid, tannins, stachyose, and vicine of FB seeds decreased by 30.8%, 55.2%, 47.0%, and 35.3%, respectively, after soaking for 12 hr before cooking in tap water (3 ml/g dry seeds). Moreover, the TIA content of FB seeds significantly reduced by 50.0% and 59.6% after extrusion at 135 ± 10°C for 10 s and 52-137°C with the final pellet temperature of 121°C, respectively, while tannins were hardly affected by extrusion method (Hejdysz et al., 2016;Konieczka et al., 2020). In addition, inactivation of 41.0%, 60.0%, 40.7%, and 39.7% of the phytic acid, tannins, convicine, and vicine occurred in FB seeds after autoclaving at 121°C for 30 min, respectively (Khalil & Mansour, 1995).
Contrary to the effects of a single processing method, autoclaving treatments may be optimal for reducing major ANFs.
Relative to the preprocessing methods used, selective breed- value. In addition, Prabhu and Rajeswari (2018) reported that γaminobutyric acid and diamine oxidase also modified the ANFs of legumes.
Overall, the literature suggests that various processing methods markedly inactivate or reduce the ANFs of FB seeds; this is especially TA B L E 8 Nutrient and energy digestibility, and N retention of faba bean (FB, g/kg) seed summarized from several references and different animal species true for heat treatments, which have been highly effective in reducing ANFs.

| Improving the nutritive value of faba bean seeds
The proximate nutritional composition and essential amino acid and mineral contents (except for potassium and magnesium) of FB seed only change slightly when subjected to cooking, autoclaving, flaking, and germination (Table 11) (Ferruzzi et al., 2009;Khalil & Mansour, 1995;Schwediauer et al., 2018). The extrusion treatment caused a marked reduction in the NDF, EE, and resistant starch contents of FB seeds, while it did not affect other chemical parameters or the amino acid profile of the FB seed (Hejdysz et al., 2016;Lestingi et al., 2015;Masoero et al., 2005).
Cooking, autoclaving, dehulling, flaking, extrusion, and germination changed the in vitro digestibility of the nutrients in FB seeds. In vitro CP digestibility of FB seeds significantly increased by 10.2%, 14.1%, and 11.8% after cooking in tap water (3 ml/g dry seeds), autoclaving at 121°C for 30 min, and germinating at room temperature for 3 days, respectively, because of the reduction or inactivation of ANFs (Khalil & Mansour, 1995). However, cooking, autoclaving, and germinating improved PER slightly (Khalil & Mansour, 1995). The apparent digestibility of EE and ME of FB seeds increased significantly by 8.17% and 4.43%, respectively, after extrusion at 135°C for 10 s with a moisture content of 22% (Hejdysz et al., 2016). Dehulling and flaking the FB seeds significantly increased their in vitro OM digestibility (by 8.64% and 1.20%, respectively) and in vitro NDF digestibility (by 74.3% and 6.95%, respectively); however, the cooking and germination treatments did not increase this digestibility and even reduce the digestibility in some cases (Ferruzzi et al., 2009  Traditional breeding approaches coupled with gene transfer studies and functional genomics would be useful for the breeding of FB lines and the development of new FB cultivars with novel protein profiles or properties with added value (Gutierrez et al., 2007;Robinson et al., 2019). Avila et al. (2007) also reported that codominant markers could promote the breeding process of FB and be useful for the quality control of FB seeds.
Overall, the literature suggests that the nutritional value of FB seeds is improved by various processing methods, especially extrusion treatment, through the inactivation or reduction in the ANFs.

| Lactating ruminants
In the Liponi et al. (2007) study, raw FB seeds replaced SBM at inclusions of 320 g/kg in the concentrate of lactating Massese ewes without affecting the milk yield, or milk fat, protein, and lactose content (Table 12), which is consistent with Mordenti et al. (2007) who found that Holstein dairy cows fed a concentrate of 345 g/kg DM FB seeds had a similar productive performance to cows fed with an SBM concentrate (150 g/kg DM). Puhakka et al. (2016) evaluated the effects of partially or completely substituting FB seeds for rapeseed meal on the milk production and composition of Finnish Ayrshire cows.
However, higher inclusion levels of 350 g/kg DM somewhat reduced the milk yield, although no differences in DM intake and milk yield were found at FB inclusions ≤345 g/kg DM of concentrate (Puhakka et al., 2016).
The total replacement of raw bitter vetch (Vicia ervilia) seeds with raw FB seeds on milk yield and composition of dairy goats produced no differences in milk yield, or milk fat, protein, and lactose contents (Morales et al., 2008). In another study, substituting a raw or rolled FB seed (at a level of 171 g/kg DM diet) for SBM (at a level of 9.2 g/ kg DM diet) did not affect the milk yield, or milk fat, protein, and lactose content of lactating Holstein cows (Cherif et al., 2018).

| Growing ruminants
Using male Comisana lambs, Bonanno et al. (2012) evaluated the nutritive value of raw FB seeds in diets where raw FB seeds replaced SBM in the concentrate in proportions of 250:0 and 0:758 g/kg for SBM and FB seeds, respectively (Table 13). They reported that no differences were found in average daily feed intake (ADFI), average daily gain (ADG), feed conversion rate (FCR), or carcass yield (Bonanno et al., 2012). Furthermore, male Fabrianese lambs fed a concentrate with 242 g/kg raw FB seeds had a similar productive performance to lambs fed a SBM concentrate (160 g/kg) (Polidori et al., 2018).
In an 8-week experiment, male Barbaresca lambs that were fed either a SBM diet (206 g/kg) or a FB seed diet (538 g/kg) had similar final body weight (BW, 27.1 kg) and ADG (0.226 kg/day) [60]. In another study, Lestingi et al. (2015) studied the effects of partially and completely substituting raw FB seeds for lupin on the productive performance of growing lambs. The lambs were fed diets containing lupin seed to FB seed ratios of 250:0 g/kg (control), 150:150 g/kg, and 0:300 g/kg, and increasing the raw FB seed content in the diet accelerated the productive performance. For Charolais heifers, animals fed a diet of 280 g/kg FB seeds had similar final BW, ADG, and ADFI to heifers fed the SBM control diet (140 g/kg); however, the FB seed diet has significantly less FCR compared with the SBM diet (Ragni et al., 2018).
In addition, Fabrianese entire male lambs slaughtered at 145 days of age did not differ in terms of their slaughter performance or the physical and chemical traits of their longissimus dorsi muscle when fed with a SBM diet (160 g/kg of diet) or a diet containing 242 g/kg of raw FB seeds (Polidori et al., 2018). Similarly, Bonanno et al. (2012) also found that slaughter parameters, physical and chemical characteristics of the longissimus dorsi muscle, and perirenal fat color of lambs slaughtered at ~129 days of age were not affected when raw FB seeds were added to the concentrate, even at 758 g/kg.
Gentile di Puglia male lambs slaughtered at 98 days of age had similar carcass traits and nutritional composition of leg and loin tissue among dietary treatments containing raw FB seeds up to 300 g/kg (Lestingi et al., 2015). Similarly, diets supplemented with 538 g/kg raw FB seeds had no effect on carcass yield and fat yield, lean meat yield, or the physical, chemical, and sensory traits of their longissimus dorsi muscle compared with the SBM control diet (206 g/kg) (Lanza et al., 1999). Charolais heifers slaughtered at approximately 119 kg BW did not differ in slaughtering parameters and dissection parameters of the pelvic limb and lumbar region as well as physical and chemical characteristics of meat from longissimus lumborum muscle (Ragni et al., 2018).
Overall, the literature suggests that substituting FB seeds for SBM or other legume seeds results in equal or somewhat increased growth as well as increased milk yield and composition in ruminants.

| Pigs
Using female pigs, O'Doherty and McKeon (2001) reported on the nutritive value of raw and extruded FB seeds in their diets (Table 14).
The pigs were fed diets that included 0, 125, 250, and 375 g/kg of raw FB seeds and 0, 250, and 375 g/kg of extruded FB seeds, respectively. Increasing the FB content in the diet did not affect the FCR and carcass characteristics, while no differences were observed in ADFI and ADG in the raw FB seed inclusion groups; however, ADFI and ADG declined linearly with increasing extruded FB seed in the diet. In addition, Gunawardena et al. (2010) found that substituting raw or dehulled FB seeds (160 g/kg) for soy protein concentratecorn gluten meal-menhaden meal diets (160 g/kg) did not affect the final BW, ADFI, ADG, and FCR of weaned pigs compared with control diet (without the FB seeds). Moreover, Schwediauer et al. (2018) reported that raw or germinated FB seeds (160 g/kg) could partially replace peas at inclusion levels of 160 g/kg in the diet without affecting the final BW, ADFI, ADG, and FCR of weaner piglets, while germinated FB seeds at a higher inclusion level of 240 g/kg in the diet could adversely affect the piglets' productive performance (Schwediauer et al., 2018).
In addition, Grabež et al. (2020) showed that Norwegian crossbred pigs that were fed a SBM diet (143 g/kg) or a FB seed diet (161 g/kg) had similar growth performances, carcass characteristics, meat quality, and mostly similar fatty acid composition of longissimus thoracis muscle. Smith et al. (2013) studied the effects of partially and completely substituting raw FB seeds for SBM on the growth performance and carcass quality of growing/ finisher pigs. SBM and FB seeds were fed to pigs in proportions of 140:0, 105:75, 70:150, 35:225, and 0:300 g/kg, and no differences were found in the FB seed inclusion groups in terms of the ADFI, ADG, FCR, carcass quality, or backfat skatole content (Smith et al., 2013).
Overall, the literature suggests that substituting SBM or peas for FB seeds in pig feedstuffs does not affect their growth performance, carcass characteristics, or meat quality.

TA B L E 1 2
The effect of faba bean (FB; g/kg DM, unless otherwise stated) seed on performance of lactating ruminants summarized from several references and different animal species (FI), egg production (EP), and egg weight (EW) compared with the SBM control diet, while FB seeds at higher inclusion level of 100 g/ kg in the diet positive affected the egg shape index and yolk color (Moujahed et al., 2020). Laudadio and Tufarelli (2010) showed that laying hens fed with a 240 g/kg diet of FB seeds had a similar productive performance to those fed the SBM control diet (150 g/ kg). In contrast, layers that were fed diets with 298 g/kg of raw FB seeds had similar final BW, FI, EW, and eggshell strength as layers fed SBM diets (72.0 g/kg), while the EP of the former was reduced by 12.8% compared with that of the latter (Laudadio & Tufarelli, 2010). Similarly, Abd el-Hack et al. (2017) showed that raw FB seeds could partially replace SBM at a level of 110 g/kg without affecting the FI, EP, egg mass (EM), EW, feed efficiency (FE), or egg quality criteria of Hisex Brown laying hens; however, higher inclusion levels of 165 or 220 g/kg adversely affected the hens' egg production and quality.
A study by Olaboro et al. (1980) studied the effect of substituting FB seeds (400 g/kg) processed in three different ways (dehulled, autoclaved at 121°C for 30 min, and dehulled and autoclaved at 121°C for 30 min) for raw FB seeds on the egg-laying performance of layers (Table 15). The authors found no differences among the processed FB seed groups in terms of their average FI studied the nutritive value of raw and expanded FB seeds (0, 50, and 100 g/kg) in the diets of laying hens. Increasing FB seed content in the diet did not affect the FI and EP, and there were no differences between raw and expanded FB groups, while the EM declined and FE increased in both groups (Koivunen, Tuunainen, Valkonen, et al., 2014).  (Table 16; Koivunen, Tuunainen, Valkonen, et al., 2014). No differences were observed in the growth performance of the lower FB seed inclusion level group and the SBM group; however, the highest FB seed inclusion group had a 10.9% lower daily feed consumption (DFC) and 5.59% lower BW gain than the SBM group (Koivunen, Tuunainen, Valkonen, et al., 2014). In contrast, DFC, meat traits, content of muscles, and fat, as well as major physicochemical parameters of breast muscles and leg muscles for male ROSS 308 chicks were not affected in SBM substitutions of 250:0 g/kg (control) versus 0:250 g/ kg (Biesek et al., 2020). However, broilers fed FB seeds had significantly 29.1% higher FCR and 18.9% lower ADG than the SBM control diet (Biesek et al., 2020). Increasing the dehulled FB seed ratio up to 250 g/kg in broiler chickens' diets did not affect the growth performance of broilers [38], which can be attributed to the improved nutrient composition and in vitro digestibility of nutrients as well as the reduced tannin content of the dehulled FB seeds (Ferruzzi et al., 2009). Furthermore, in a 4-week experiment, female Ross 308 broiler chickens fed either a raw or extruded (300 g/kg) FB seed diet had a similar DFC (112 g), ADG (78.2 g/day), and FCR (1.44) (Konieczka et al., 2020).
Overall, the literature suggests that adding FB seeds to layer or broiler diets does not affect the EP of layers or the EP and growth performance of broilers.

| Fish
In a study by Adamidou, Nengas, Henry, et al. (2009) that fish might be susceptible to the adverse effects of the ANFs found in diets with more raw FB seeds.
Overall, the literature suggests that substituting low amounts of raw FB seeds for SBM and cereal grains in fish diets do not affect the growth performance of fish.

| CON CLUS IONS
FB seeds are high in protein and energy and are used as an alternative feedstuff in livestock production. To support higher growth and/or productive performance of animals, raw FB seeds can be generally included in cow concentrate and lamb diets at appropriate levels as 175 and 300 g/kg, respectively, while raw FB seeds can be used in pig, layer, broiler (6-32 days of age), and fish diets at appropriate levels of up to 300, 110, 160, and 420 g/kg, respectively. The inclusion of higher levels of FB seeds in pig, poultry, and fish diets is possible after the ANFs have either been eradicated or reduced with the use of preprocessing treatments to improve the nutritional value of the seeds. Of the preprocessing treatments, extrusion treatment facilitates the inclusion of higher FB seed levels in the diets of nonruminants without any adverse effects on their performance.

ACK N OWLED G M ENTS
This research was conducted with funding from the National Key

CO N FLI C T O F I NTE R E S T
The authors declare that they have no competing interests.

E TH I C A L A PPROVA L
No ethical approval was required, as this is a review article with no original research data.