1. Lupins (Lupinus spp.)
Lupinus is a large genus that has more than 300 species in both the Eastern and Western Hemispheres. Lupins are native to North and South America, the Mediterranean region and northern Africa. Only five species
[1], however, are cultivated and they are
L. albus (white lupin)
, L. angustifolius (narrow-leaf lupin)
, L. luteus (yellow lupin)
, L. mutabilis and
L. cosentinii (sandplain lupin). Of these five species, the first three are suitable for cultivation as high-protein crops
[2]. Based on their promise in Australasia, only the first two species are reviewed herein.
Lupin production was initially limited to white lupin cultivars. The interest in using narrow-leaf lupins as an alternative to conventional protein sources in poultry diets has been increasing in recent decades, especially in Australia. Currently, Australia is the largest lupin grain producer in the world, and the narrow-leaf lupin is the dominant species. Lupin seeds are an attractive alternative to soybeans because of their high protein content (202–424 g/kg; Table 1).
Older lupin cultivars contain various types of alkaloids of which the quinolizidine alkaloids are the most relevant antinutritional factor. Alkaloids are defined as nitrogen-containing water-soluble compounds produced in the chloroplasts of some plants with the purpose of repelling insects
[3]. Lupanine is the major alkaloid present in
L. albus and
L. angustifolius, while lupinine is present in
L. luteus [4]. Some other alkaloids such as sparteine, angustifolin and gramine are also present in
L. luteus. Based on the alkaloid content, lupin can be grouped into two categories: those with a high alkaloid content (up to 53.8 g/kg), commonly known as bitter lupins, and those with low alkaloid content (less than 0.5 g/kg), referred to as sweet lupins
[3]. Sweet lupins can either be of the white (
L. albus), yellow (
L. luteus) or blue-seeded (
L. angustifolius) cultivars
[4]. Early cultivars of lupins contained relatively high concentrations of toxic and bitter alkaloids that depressed feed intake and growth, and negatively affected the feed efficiency in broilers
[5][6]. However, modern plant breeding techniques have now enabled the development of low-alkaloid lupin cultivars. For example, current Australian sweet lupins are known for their virtually zero alkaloid content (less than 0.4 g/kg;
[7]).
1.1. Lupinus angustifolius
This lupin species is referred to as narrow leaf lupin, narrow-leaved lupin or blue lupin. This is an annual herb that can reach 80 cm or more in height. The inflorescence of sweet lupins bears many flowers that are usually blue in colour but can also range from white to pink
[2]. The seeds of sweet lupin have variable colours from dark gray to brown to white, and can be speckled or mottled. As noted above, cultivars with a low alkaloid content are called sweet lupins. This species contains a single recessive gene that controls sweetness. The bitter form of the gene causes seeds to have a high alkaloid content that can be poisonous and cause liver damage. For almost a century, plant breeders have been developing cultivars with lower alkaloid content. Culvenor and Petterson
[8] reported that some sweet lupins can contain as low as 0.02 g/kg alkaloids. The alkaloid content of bitter lupins could be 1000 times greater than sweet lupins, but these cultivars have a higher seed yield
[2].
In Australia, sweet lupins dominate the commercial market. The nutritional composition of sweet lupins is acknowledged by the feed manufacturers. However, the nutritional variability between cultivars
[9][10][11] is a major challenge. Reported analysis for the crude protein content of sweet lupins ranges from 223 to 409 g/kg dry matter [DM] (
Table 1). This variation is largely caused by differences in cultivars, production location and year, and agronomic management
[11][12].
Table 1. The nutritional composition (g/kg, dry matter basis) of Australian sweet lupins.
Kingwell
[12] reported that the protein and oil contents of sweet lupins are related to seed size. There was a tendency for bigger seeds to have higher protein and oil contents compared to the smaller seeds in the same cultivar. In comparison with field peas and faba beans, which contain more than 300 g/kg starch, the starch content of lupins is very much lower. Some lupin cultivars are reported to be completely devoid of starch
[28]. The carbohydrate profile of lupins is dominated by structural carbohydrates, neutral detergent fibre and acid detergent fibre. The high soluble oligosaccharide content restricts wider acceptance of sweet lupins in poultry diets
[29].
The proportion between hull and kernel, and their nutrient composition differ depending on the species of lupins
[12]. The proportion of the seed coat in sweet lupins is about 230 g/kg. The seed coat contains mainly cellulosic fibre, while kernels comprise 300 g/kg cell wall materials, and pectin-like dietary fibres.
Published data on the AA content of Australian sweet lupins is summarised in Table 2. The AA profile is similar to other legume proteins, being high in lysine and low in sulphur-containing AAs and tryptophan. These limiting AAs can be supplemented with synthetic forms in diets containing sweet lupins. There may also be possibilities to increase the AA content through molecular techniques. It is worth noting that high-methionine transgenic lupins, containing 4.5 g/kg methionine, have been developed in Australia (Table 2).
Table 2. Amino acid content (g/kg, dry matter basis) of Australian sweet lupins.
Amino Acids |
References |
[13] |
[15] |
[16] 1 |
[17] 2 |
[17] 3 |
Essential |
|
|
|
|
|
Arginine |
31.5 |
11.7 |
34.4 |
29.9 |
31.7 |
Histidine |
11.0 |
3.1 |
8.0 |
7.6 |
7.6 |
Isoleucine |
13.8 |
5.2 |
12.6 |
11.4 |
11.4 |
Leucine |
21.9 |
7.9 |
20.8 |
20.6 |
21.1 |
Lysine |
15.0 |
5.1 |
12.9 |
13.8 |
14.2 |
Methionine |
2.6 |
0.8 |
1.8 |
2.0 |
4.5 |
Phenylalanine |
12.2 |
4.3 |
12.5 |
10.8 |
10.6 |
Threonine |
11.6 |
3.7 |
10.9 |
10.0 |
10.2 |
Valine |
13.8 |
4.7 |
12.2 |
11.2 |
11.2 |
Tryptophan |
na |
0.8 |
na |
2.8 |
2.9 |
Non-essential |
|
|
|
|
|
Alanine |
11.0 |
4.0 |
10.7 |
10.0 |
10.4 |
Aspartic acid |
30.8 |
11.0 |
29.4 |
29.4 |
30.8 |
Cysteine |
2.5 |
1.5 |
33 |
3.6 |
3.7 |
Glycine |
13.4 |
4.6 |
12.9 |
12.1 |
12.6 |
Glutamic acid |
64.2 |
26.8 |
56.0 |
65.1 |
65.6 |
Proline |
11.7 |
4.8 |
13.2 |
na |
na |
Serine |
16.4 |
5.7 |
15.2 |
14.4 |
14.1 |
Tyrosine |
11.1 |
3.0 |
10.2 |
9.5 |
10.2 |
Apparent Metabolisable Energy
The AME of sweet lupins differs between cultivars (
Table 3), from 6.04 to 11.64 MJ/kg DM basis. Hughes et al.
[30] reported that the AME of a cultivar (cv. Gungurru) of Australian sweet lupins from three Western Australian sites ranged from 9.8 to 12.3 MJ/kg. Observed variation within a cultivar reflects the differences in climate, soil and agronomic conditions. The low energy utilisation may be explained by the high content of non-starch polysaccharides (NSPs; soluble and insoluble) and extremely low content or lack of starch.
Table 3. The apparent metabolisable energy values (MJ/kg dry matter basis unless otherwise specified) of Australian sweet lupins.
Cultivar |
AME |
Nitrogen-Corrected AME (AMEn) |
References |
Unknown |
9.99 * |
9.85 * |
[13] |
Danja |
6.50–10.50 |
- |
[29][31] |
Gungurru |
6.53–11.64 |
- |
[16][29][31][32][33] |
Warrah |
9.42 |
- |
[17] |
Transgenic lupin |
10.18 |
- |
[17] |
Wallan |
6.38 |
5.35–5.82 |
[22][23] |
Tanjil |
6.73 |
6.18 |
[23] |
Borre |
7.12 |
5.52 |
[23] |
Boruta |
- |
9.27 |
[34] |
Neptun |
- |
8.67 |
[34] |
Sonet |
- |
9.16 |
[34] |
Graf |
- |
7.91 |
[34] |
Pershatvet |
7.00 |
- |
[35] |
Kadryl |
7.37–8.40 |
- |
[36] |
Regent |
6.04–6.88 |
- |
[36] |
Dalbor |
6.71–7.68 |
- |
[36] |
Bojar |
8.52–9.25 |
- |
[36] |
Tango |
7.60–7.74 |
- |
[36] |
Amino Acid Digestibility
Available data on the apparent ileal AA digestibility coefficient of sweet lupins for broilers are summarised in
Table 4. The AA digestibility in Australian sweet lupins is high and similar to those reported for SBM
[17][37]. A lysine digestibility of 0.87–0.91 was reported in caecectomised laying hens
[38].
Feeding Trials
Early research indicated that sweet lupins are not a suitable protein source in broiler diets. Olkowski et al.
[6] showed the negative effects of feeding 350–400 g/kg sweet lupins (raw or dehulled or autoclaved; cv. Troll) on growth performance in young broilers and suggested that the substitution of lupin seed meal for SBM in broiler diets is only possible for broilers aged 4 weeks and above. It was speculated that the levels of alkaloids may have been responsible. Similarly, other early studies
[39][40] have shown that the use of 200 g/kg sweet lupins reduced the growth and feed efficiency of broiler starters.
Table 4. Apparent ileal amino acid digestibility coefficient of Australian sweet lupins.
Amino Acids |
References |
[17] 1 |
[18] 2 |
[23] 3 |
[34] 4 |
[35] 5 |
[41] |
[42] |
Essential |
|
|
|
|
|
|
|
Arginine |
0.90 |
na |
0.94 |
0.84 |
0.93 |
0.89 |
0.93 |
Histidine |
0.84 |
0.84 |
0.79 |
0.76 |
0.86 |
0.84 |
0.78 |
Isoleucine |
0.82 |
0.84 |
0.85 |
0.83 |
0.87 |
0.81 |
0.82 |
Leucine |
0.84 |
0.81 |
0.87 |
0.84 |
0.88 |
0.83 |
0.85 |
Lysine |
0.78 |
0.85 |
0.87 |
0.82 |
0.89 |
0.83 |
0.84 |
Methionine |
0.83 |
0.85 |
0.79 |
na |
0.79 |
0.82 |
0.76 |
Phenylalanine |
0.83 |
0.82 |
0.89 |
0.83 |
0.85 |
0.83 |
0.87 |
Threonine |
0.76 |
0.78 |
0.82 |
0.76 |
0.80 |
0.77 |
0.79 |
Tryptophan |
0.79 |
0.76 |
na |
na |
na |
na |
na |
Valine |
0.80 |
0.77 |
0.83 |
0.80 |
0.89 |
0.80 |
0.80 |
Non-essential |
|
|
|
|
|
|
|
Alanine |
0.80 |
na |
0.83 |
0.81 |
0.87 |
0.80 |
0.82 |
Aspartic acid |
0.82 |
na |
0.84 |
0.78 |
0.87 |
0.82 |
0.81 |
Cysteine |
0.69 |
na |
0.83 |
na |
0.77 |
0.78 |
0.82 |
Glycine |
0.82 |
0.80 |
0.82 |
0.75 |
0.83 |
0.82 |
0.81 |
Glutamic acid |
0.89 |
na |
0.91 |
0.87 |
0.92 |
0.86 |
0.90 |
Proline |
na |
na |
0.82 |
0.80 |
0.82 |
na |
0.80 |
Serine |
0.81 |
na |
0.82 |
0.77 |
0.82 |
0.80 |
0.79 |
Tyrosine |
0.85 |
0.79 |
0.84 |
0.78 |
0.76 |
0.83 |
0.84 |
A number of other studies, on the other hand, have demonstrated that sweet lupins can be safely used in poultry diets. The observed discrepancy may be explained by cultivar differences in the contents of alkaloids and NSPs, and the failure to consider the low AME in feed formulations. Nalle et al.
[23] reported that narrow leaf lupins (cv. Wallan, Tanjil and Borre) can be included at 200 g/kg in broiler starter diets when the diets are properly balanced for AME and digestible AAs. Farrell et al.
[39] studied different inclusion rates of lupins and suggested an inclusion level of less than 100 g/kg for broilers. van Barneveld
[29], in contrast, indicated that lupins could be used in broiler diets up to 250 g/kg. Perez-Maldonado et al.
[16] did not find any negative effect from feeding sweet lupins at 250 g/kg on the performance of laying hens when compared to field peas and faba beans. However, the same study reported an increased digesta viscosity and weight of pancreas at 250 g/kg sweet lupin. Perez-Escamilla et al.
[43] similarly found that lupin inclusion level of 300 g/kg could support the performance of broilers without any detrimental effects. According to Hughes et al.
[31], whole seeds of lupins can be included up to 200 and 300 g/kg in wheat-based and maize-based diets, respectively, for broilers. Brand et al.
[44] reported that SBM can be replaced with sweet lupins up to 300 g/kg in the diet of grower ostriches. It is, however, worth noting that higher inclusion levels of lupins could increase the incidence of wet litter
[29][31]. At 200 g/kg inclusion, the excreta quality was not affected
[23].
1.2. Lupinus albus
This lupin species is commonly known as white lupin or field lupin. The colour of the white lupin flowers are greyish-blue or white. This species is mainly distributed around the Mediterranean region, Europe, South America and tropical and southern Africa
[45][46]. Seeds of white lupin are large, flat, rectangular or square-shaped with rounded corners, compress laterally and are about 7–16 mm long and 6–12 mm high
[47].
The alkaloid content of bitter cultivars ranges from 5 to 40 g/kg, while those of low-alkaloid cultivars range between 0.08 and 0.12 g/kg
[46]. Alkaloid-free cultivars of white lupins are also available, and the development of these alkaloid-free mutants has allowed the exploitation of white lupins as a protein source for animals.
White lupins contain moderate to high contents of crude protein (202–424 g/kg), crude fat (60–130 g/kg), and fibre content (105–162 g/kg) as summarised in
Table 5. The considerable variation observed in the nutritional content of white lupins probably reflects genetic and environmental differences
[45][46][47]. Brenes et al.
[48] reported that the high portion of hull (16% of the seed) was mainly responsible for the high fibre content of the whole seed. Thus, the removal of the hull will markedly decrease the fibre content. White lupins have only a negligible amount of starch
[49], but high amount of soluble and insoluble NSPs and oligosaccharides
[18][29][33]. The oligosaccharide content is the feature which most often appears to limit their wider use in poultry diets.
Table 5. The nutritional composition (g/kg, dry matter basis) of white lupins.
Table 6 summarises the published data on the AA composition and indicates that white lupins are deficient in methionine, cysteine and tryptophan, but good sources of other essential AAs. Similar to sweet lupins
[17], there may be possibilities to increase the content of methionine in white lupins through modern plant breeding techniques. However, to the best of authors’ knowledge, there are no published data on breeding techniques to improve the cysteine or tryptophan content of grain legumes. The AA composition of white lupins has been shown to differ from other lupin species (
L. angustifolius and
L. luteus) with higher concentrations of threonine, tyrosine and isoleucine
[61]. In general, white lupin has higher AA (total and essential) content than Australian sweet lupins
[15][18][21].
Table 6. Amino acid content (g/kg, dry matter basis) of white lupins.
Amino Acid |
References |
[15] 1 |
[49] 2 |
[50] 3 |
[51] 4 |
[59] |
[62] |
[63] 5 |
[64] 6 |
Essential |
|
|
|
|
|
|
|
|
Arginine |
11.4 |
36.3 |
38.4 |
28.0 |
43.1 |
29.9 |
35.8 |
38.6 |
Histidine |
2.5 |
8.8 |
9.0 |
7.0 |
9.4 |
7.1 |
5.9 |
8.3 |
Isoleucine |
5.3 |
13.4 |
17.9 |
14.0 |
18.0 |
15.2 |
17.1 |
14.3 |
Leucine |
8.3 |
26.0 |
28.6 |
25.7 |
28.7 |
23.3 |
23.4 |
24.3 |
Lysine |
5.1 |
16.7 |
16.4 |
16.2 |
19.3 |
15.9 |
17.4 |
16.4 |
Methionine |
0.7 |
2.8 |
2.6 |
6.5 |
na |
3.4 |
2.9 |
2.6 |
Phenylalanine |
4.1 |
13.1 |
16.1 |
14.6 |
na |
11.9 |
13.7 |
12.4 |
Threonine |
4.0 |
13.7 |
14.3 |
13.1 |
14.8 |
8.0 |
14.7 |
11.6 |
Valine |
4.9 |
13.7 |
15.1 |
13.8 |
17.2 |
15.0 |
10.6 |
14.5 |
Tryptophan |
0.8 |
na |
2.3 |
3.2 |
3.2 |
na |
3.4 |
na |
Non-essential |
|
|
|
|
|
|
|
|
Alanine |
3.7 |
12.0 |
12.7 |
na |
na |
10.9 |
na |
10.2 |
Aspartic acid |
11.6 |
34.4 |
45.7 |
na |
na |
33.8 |
na |
33.6 |
Cysteine |
1.4 |
5.3 |
5.5 |
7.5 |
na |
na |
3.7 |
5.1 |
Glycine |
4.2 |
12.7 |
14.9 |
13.4 |
na |
12.8 |
na |
13.4 |
Glutamic acid |
25.6 |
64.7 |
88.6 |
na |
na |
62.6 |
na |
58.6 |
Proline |
3.9 |
11.9 |
16.5 |
na |
na |
na |
na |
12.8 |
Serine |
5.7 |
15.0 |
23.9 |
na |
na |
8.8 |
na |
14.6 |
Tyrosine |
5.1 |
13.8 |
17.6 |
na |
na |
9.8 |
na |
13.4 |
Apparent Metabolisable Energy
The AME values of white lupins have been reported to range from 8.1 to 13.3 MJ/kg (
Table 7). The higher AME content of white lupins compared to Australian sweet lupins (
Table 3) is due to their higher oil content
[65].
Table 7. Apparent metabolisable energy (MJ/kg, dry matter basis) of white lupins.
Cultivar |
AME |
Class of Poultry |
References |
Amiga (alkaloid-free) |
9.90 |
Broilers |
[48] |
Ultra |
9.20 |
Roosters |
[43] |
Kiev mutant |
9.58–13.29 |
Broilers |
[29][31][33][49][66] |
Promore |
9.68 |
Broilers |
[49] |
Ultra |
8.05 |
Broilers |
[49] |
Amino Acid Digestibility
Amino acids in white lupins are well digested (Table 8), with most AAs having digestibility coefficients of over 0.80.
Table 8. Apparent ileal amino acid digestibility coefficient of white lupins for broilers.
Amino Acid |
References |
[41] |
[49] 1 |
[66] 2 |
Essential |
|
|
|
Arginine |
0.88 |
0.95 |
0.97 |
Histidine |
0.81 |
0.81 |
0.82 |
Isoleucine |
0.77 |
0.88 |
0.86 |
Leucine |
0.79 |
0.89 |
0.88 |
Lysine |
0.81 |
0.90 |
0.90 |
Methionine |
0.84 |
0.83 |
0.79 |
Phenylalanine |
0.79 |
0.92 |
0.92 |
Threonine |
0.75 |
0.84 |
0.80 |
Valine |
0.75 |
0.85 |
0.86 |
Tryptophan |
na |
na |
na |
Non-essential |
|
|
|
Alanine |
0.78 |
0.85 |
0.84 |
Aspartic acid |
0.80 |
0.87 |
0.78 |
Cysteine |
0.83 |
0.81 |
0.84 |
Glycine |
0.79 |
0.86 |
0.87 |
Glutamic acid |
0.85 |
0.93 |
0.84 |
Proline |
na |
0.85 |
0.85 |
Serine |
0.78 |
0.85 |
0.87 |
Tyrosine |
0.81 |
0.88 |
0.88 |
Feeding Trials
The feeding value of lupins is determined, to a large extent, by the concentration of alkaloids in the seed. As discussed above, these bitter substances can influence the feed intake and growth in poultry and limit the utilisation of white lupins. However, with the development of new cultivars with low alkaloid content (<0.1 g/kg), this is no longer an issue.
Nalle et al.
[67] reported that when balanced for AME and digestible AA, white lupins can be used at 200 g/kg in wheat–SBM and wheat–SBM–meat meal-based diets for broilers up to 35 days of age. Dietary lupin concentrations of 50–300 g/kg have also been shown to support the growth performance of broilers without any adverse effects
[43][68]. Olver
[69] reported that feeding broilers up to 8 weeks with 400 g/kg white lupins (alkaloid content, <0.1 g/kg) showed no adverse effects on growth, feed efficiency or carcass characteristics. Similarly, Olver and Jonker
[63] reported that broiler chickens can tolerate up to 400 g/kg of white lupins (cultivar Hanti) without compromising their growth. A similar trend was also found in the feeding of ducklings
[51] up to 6 weeks of age with diets containing up to 400 g/kg white lupins (cv. Buttercup). Increased egg yolk colour was reported in laying hens fed diets containing 100–300 g/kg lupins (cv. Ultra)
[70]. It was concluded that this lupin cultivar could replace all the SBM in broiler diets and that white lupins do not exert any antinutritive effect provided that the concentration of alkaloids is less than 0.1 g/kg. In contrast, Olkowski et al.
[71] reported a significant decrease in feed intake and weight gain in broilers fed a diet containing 400 g/kg raw white lupin seeds. This could be because of high-alkaloid content of white lupin. Feed intake and body weight are reduced with increasing dietary lupin concentrations (0.12–3.64 g/kg) as reported by Pastuszewska et al.
[72]. The bitterness due to the high alkaloid content in lupins may reduce the feed intake and consequently the weight gain in birds. According to Kaczmarek et al.
[73] and Kubiś et al.
[74], the AME of diets linearly decreased with increasing inclusions of white lupins from 0 to 300 g/kg in the diets. Kaczmarek et al.
[73] reported a growth depression in broilers fed the diets with >150 g/kg white lupins. A similar negative effect was also reported in turkey poults where there were 6, 11 and 15% reductions in the growth observed in 3-week-old poults fed diets with 300, 450 and 600 g/kg white lupin, respectively
[62].
2. Field Peas
Field pea seeds can be smooth or wrinkled, and green, white or brown in colour. The average weight of seed is about 200 mg, with the seed coat contributing around 12% of the total seed weight
[7]. The distinction between different field peas is made by the colour of the tegument (translucent without tannins and coloured with tannins) and the colour of the cotyledons.
Wide variability can be seen in the proximate composition of field peas (
Table 9) and reflects the differences in cultivar, growing condition, and analytical methods. Field peas are a moderately high-quality source of protein and starch. Compared to SBM, field peas have lower protein content, ranging from 114 to 301 g/kg DM (
Table 9). Field pea protein is reported to be highly digestible with an excellent AA balance
[2]. Similar to other legumes, field peas are deficient in sulphur-containing AAs (
Table 10). Lysine concentration is relatively high in field peas. The predominant fraction of field pea carbohydrates is starch, having an average content of 413 g/kg DM (
Table 9). The fat content of field pea is very low (6.5–27 g/kg DM). The crude fibre content of field peas is higher (average of 101 g/kg DM) than that of SBM (38 g/kg;
[74][75].
Table 9. Nutritional composition (g/kg, dry matter basis) of field peas.
2.1. Apparent Metabolisable Energy
The reported AME values of field peas range between 8.3 and 12.3 MJ/kg (Table 11) and this variation was associated with cultivars and the age and class of birds. In general, the energy value of field peas is higher compared to those of faba beans and lupins, due mainly to their high starch content.
2.2. Amino Acid Digestibility
The AA digestibility values (
Table 12) in field peas vary depending on the cultivar and, age and class of birds. Szczurek and Świątkiewicz
[89] reported a higher standardised ileal AA digestibility in field peas for 28-day old broilers than for 14-day old broilers. In the same study, a higher digestibility was determined for a white-flowered field pea (cv. Tarchalska) than for a coloured-flowered cultivar (cv. Milwa). A similar cultivar effect was recently reported by Adekoya and Adeola
[90] for standardised ileal AA digestibility in broilers fed three field pea cultivars (cv. DS-Admiral, Hampton and 4010).
Table 10. Amino acid content (g/kg, dry matter basis) of field peas.
Amino Acid |
References |
[13] |
[15] 1 |
[16] |
[41] |
[42] |
[50] |
[82] 2 |
[88] 3 |
[91] |
Essential |
|
|
|
|
|
|
|
|
|
Arginine |
22.0 |
10.9 |
24.3 |
25.2 |
22.0 |
16.1 |
21.1 |
12.4 |
21.1 |
Histidine |
6.2 |
2.8 |
5.8 |
6.6 |
6.5 |
4.3 |
6.3 |
5.1 |
6.3 |
Isoleucine |
10.2 |
5.1 |
9.4 |
10.2 |
9.7 |
9.9 |
9.4 |
7.3 |
10.9 |
Leucine |
16.8 |
8.2 |
16.6 |
17.5 |
17.5 |
16.0 |
16.7 |
12.7 |
18.3 |
Lysine |
17.0 |
8.3 |
14.2 |
17.1 |
17.3 |
14.8 |
17.3 |
14.0 |
18.8 |
Methionine |
2.3 |
1.0 |
1.9 |
2.2 |
2.6 |
2.0 |
2.5 |
2.2 |
2.7 |
Phenylalanine |
11.0 |
5.2 |
11.1 |
11.5 |
10.9 |
10.8 |
11.1 |
8.9 |
11.9 |
Threonine |
9.0 |
4.1 |
8.5 |
9.6 |
9.0 |
9.2 |
8.6 |
7.5 |
10.2 |
Tryptophan |
na |
0.9 |
na |
na |
na |
2.0 |
na |
1.4 |
2.3 |
Valine |
12.3 |
5.5 |
10.8 |
12.0 |
10.5 |
10.3 |
10.3 |
8.3 |
13.0 |
Non-essential |
|
|
|
|
|
|
|
|
|
Alanine |
10.4 |
5.0 |
10.1 |
11.3 |
10.0 |
10.1 |
9.8 |
8.1 |
11.4 |
Aspartic acid |
26.7 |
12.5 |
25.4 |
28.6 |
28.6 |
30.1 |
26.6 |
20.9 |
28.9 |
Cysteine |
1.8 |
1.4 |
3.2 |
3.5 |
3.1 |
3.4 |
3.3 |
3.5 |
3.5 |
Glycine |
10.3 |
4.7 |
10.1 |
10.9 |
10.4 |
9.7 |
9.9 |
7.7 |
11.1 |
Glutamic acid |
39.7 |
22.3 |
38.4 |
41.3 |
39.6 |
39.3 |
37.3 |
29.3 |
45.1 |
Proline |
8.4 |
4.6 |
9.7 |
na |
9.6 |
9.7 |
9.3 |
7.8 |
10.4 |
Serine |
11.8 |
5.2 |
11.1 |
12.9 |
10.3 |
12.8 |
10.0 |
8.2 |
12.1 |
Tyrosine |
7.3 |
3.0 |
6.7 |
7.6 |
8.3 |
7.0 |
7.8 |
5.7 |
7.1 |
2.3. Feeding Trials
Several studies have demonstrated the value of field peas as a protein source in poultry diets. According to Sipsas et al.
[7], poultry diets can contain up to 250 g/kg field peas with little risk of wet droppings. Similarly, an inclusion of 200–300 g/kg of field peas in the diets of broilers and layers has been reported by Perez-Maldonado et al.
[16], Farrell et al.
[39] and Castell et al.
[92]. According to Anderson et al.
[77], field peas can be fed at 200–300 and 400 g/kg in the diet for broilers and laying hens, respectively. Janocha et al.
[93] recommended inclusion levels of 100–150 and 200–250 g/kg field peas for broiler starters and growers, respectively. Brenes et al.
[94] found that the performance of broilers fed diets containing 480 g/kg of field peas was similar to those fed a maize–soy diet. However, the inclusion of 600 g/kg field peas has shown to depress the egg production, egg mass and feed efficiency in laying hens
[95].
Table 11. Apparent metabolisable energy (MJ/kg dry matter basis unless otherwise specified) of field peas.
Cultivar |
Bird Class |
AME |
AMEn |
References |
Finale |
Broilers |
- |
11.56 |
[96] |
Finale |
Adult roosters |
- |
11.77 |
[96] |
Frisson |
Broilers |
- |
10.86 |
[96] |
Frisson |
Adult roosters |
- |
11.28 |
[96] |
Impala |
Broilers |
- |
10.13 # |
[97] |
Radley |
Broilers |
- |
10.29 # |
[97] |
Sirius |
Broilers |
- |
8.28 # |
[97] |
- |
Poultry |
11.50 # |
- |
[7] |
Glenroy |
Pullets |
11.70 * |
- |
[16] |
- |
Broilers |
- |
10.2–11.3 * |
[98] |
- |
Broilers |
11.7 |
- |
[81] |
Santana |
Broilers |
10.78 |
10.16–12.30 |
[22][82] |
Miami |
Broilers |
10.15 |
9.81 |
[82] |
Courier |
Broilers |
10.39 |
9.71 |
[82] |
Rex |
Broilers |
9.82 |
9.11 |
[82] |
Sohvi |
Broilers |
12.2 |
- |
[35] |
Karita |
Broilers |
13.8 |
- |
[35] |
Tarachalska |
Broilers |
- |
9.05 * |
[99] |
Table 12. Ileal amino acid digestibility (apparent 1/standardised 2) of field peas.
Amino Acid |
References |
[41] 1 |
[88] 2,3 |
[89] 2,4 |
[90] 2,5 |
Essential |
|
|
|
|
Arginine |
0.83 |
0.89 |
0.89 |
0.92 |
Histidine |
0.75 |
0.90 |
0.85 |
0.87 |
Isoleucine |
0.71 |
0.82 |
0.80 |
0.74 |
Leucine |
0.71 |
0.83 |
0.82 |
0.85 |
Lysine |
0.83 |
0.91 |
0.87 |
0.90 |
Methionine |
0.70 |
0.90 |
0.83 |
0.83 |
Phenylalanine |
0.72 |
0.82 |
0.85 |
0.86 |
Threonine |
0.69 |
0.87 |
0.81 |
0.85 |
Tryptophan |
na |
0.78 |
na |
0.86 |
Valine |
0.71 |
0.81 |
0.82 |
0.84 |
Non-essential |
|
|
|
|
Alanine |
0.73 |
0.82 |
0.84 |
0.86 |
Aspartic acid |
0.78 |
0.77 |
0.85 |
0.87 |
Cystine |
0.66 |
0.70 |
0.76 |
0.81 |
Glutamic acid |
0.80 |
0.89 |
0.88 |
0.91 |
Glycine |
0.71 |
0.80 |
0.83 |
0.85 |
Proline |
na |
0.86 |
0.83 |
0.85 |
Serine |
0.71 |
0.79 |
0.82 |
0.87 |
Tyrosine |
0.72 |
0.82 |
0.86 |
0.87 |
3. Faba Bean
There are two types of faba beans, namely major (broad bean), with an average seed weight of 800 mg, and minor (horse bean, tic bean) with an average seed weight of 550 mg
[7]. Faba beans are mostly consumed in Mediterranean countries, China and Brazil. The breeding of new cultivars with tannin-free seeds and with low vicine and convicine contents has offered new perspectives for the feed use of faba beans
[2].
The reports on the nutrient composition of faba beans are summarised in
Table 13. The large variation in the nutritional composition of faba beans probably reflects differences in cultivar, environment, growing condition and year of harvest
[100][101]. The seeds are good sources of protein and starch (237–349 and 371–447 g/kg DM, respectively;
Table 13). According to Chavan et al.
[102], the crude protein content of faba beans varies from 200 to 410 g/kg. Rubio et al.
[100] reported that the mineral contents vary considerably between cultivars (light- vs. dark-seed-coat cultivars) and seed fractions (cotyledon vs. hull). Light-seed-coat cultivars tend to have lower mineral and phytate contents than those with a dark seed coat
[100].
Table 13. Nutrient composition (g/kg, dry matter basis) of faba beans.
The AA composition of faba bean is presented in
Table 14. Faba bean is a good source of essential AA, especially lysine (7.1–21.8 g/kg). Methionine and cysteine (0.8–2.8 and 1.4–5.8, g/kg respectively) are the limiting AAs.
Table 14. Amino acid content (g/kg, dry matter basis) of faba beans.
Amino Acid |
References |
[15] 1 |
[16] 2 |
[35] 3 |
[50] |
[108] 4 |
[109] 5 |
[111] 6 |
[112] 7 |
Essential |
|
|
|
|
|
|
|
|
Arginine |
9.8 |
26.5 |
27.8 |
26.2 |
23.8 |
24.4 |
27.9 |
25.4 |
Histidine |
3.2 |
6.7 |
8.2 |
7.1 |
6.6 |
7.2 |
Na |
8.0 |
Isoleucine |
4.8 |
10.8 |
11.7 |
12.6 |
9.2 |
12.7 |
11.0 |
11.8 |
Leucine |
8.3 |
19.2 |
21.3 |
21.3 |
16.7 |
21.6 |
21.0 |
21.2 |
Lysine |
7.1 |
14.4 |
18.6 |
18.0 |
14.0 |
18.8 |
21.8 |
17.0 |
Methionine |
0.8 |
1.7 |
2.2 |
2.4 |
2.2 |
2.2 |
2.4 |
2.8 |
Phenylalanine |
4.6 |
11.3 |
12.7 |
12.3 |
9.3 |
12.8 |
na |
12.8 |
Threonine |
3.8 |
9.4 |
10.4 |
10.2 |
7.5 |
9.7 |
6.7 |
9.1 |
Valine |
5.4 |
12.1 |
13.6 |
13.8 |
10.4 |
13.7 |
13.0 |
13.5 |
Tryptophan |
0.8 |
na |
na |
2.6 |
Na |
2.3 |
2.5 |
3.2 |
Non-essential |
|
|
|
|
|
|
|
|
Alanine |
4.5 |
10.9 |
12.5 |
12.0 |
10.1 |
13.0 |
na |
11.3 |
Aspartic |
11.9 |
27.5 |
24.3 |
28.0 |
26.1 |
30.3 |
na |
30.6 |
Cysteine |
1.4 |
3.0 |
4.1 |
3.7 |
3.6 |
3.2 |
3.9 |
5.8 |
Glycine |
4.7 |
11.0 |
12.6 |
12.0 |
9.7 |
12.0 |
na |
13.1 |
Glutamic acid |
20.7 |
40.7 |
47.1 |
48.6 |
38.2 |
47.5 |
na |
45.5 |
Proline |
4.4 |
11.2 |
12.9 |
13.4 |
8.3 |
12.2 |
na |
13.1 |
Serine |
5.3 |
12.7 |
14.1 |
14.9 |
8.9 |
12.0 |
na |
12.6 |
Tyrosine |
3.3 |
7.8 |
10.0 |
8.5 |
7.5 |
9.3 |
na |
10.1 |
3.1. Apparent Metabolisable Energy
The AME and AME
n (nitrogen-corrected AME) values reported for faba beans range from 8.8–12.4 and 8.1–12.7 MJ/kg, respectively (
Table 15), which are comparable to those in SBM (8.4–10.6 MJ/kg)
[75]. The variation in AME values is attributed to differences in cultivar and experimental methodology. Of interest is that tannin-free cultivars of faba beans tended to have higher AME values than those containing tannin. Brufau et al.
[103] reported the AME
n values of spring and winter cultivars of faba beans as 9.18 and 9.92 MJ/kg, respectively, using total collection method and as 8.56 and 8.62 MJ/kg using chromic oxide index method, respectively. The same study also reported a reduced AME (9.06 vs. 10.35 for the total collection method and 7.84 vs. 9.33 for the index method) in coloured-tannin cultivars when compared to tannin-free white cultivars. These findings are in agreement with those of Vilariño et al.
[113] who reported a reduced AME
n in high-tannin cultivars of reconstituted faba beans when compared to low-tannin cultivars. The same study
[113] also reported a negative effect of vicine and convicine on the AME
n of reconstituted faba beans. On the other hand, the inclusion of faba beans (80–240 g/kg) has been shown to increase the AME
n of diets when compared to the AME
n of the control diet
[114].
Table 15. Apparent metabolisable energy (MJ/kg dry matter basis unless otherwise specified) of faba beans for broilers.
Cultivar |
AME |
AMEn |
References |
Spring |
- |
9.2 |
[103] |
Winter |
- |
9.9 |
[103] |
Diana |
- |
8.9 |
[103] |
Fiord |
11.0–11.3 * |
- |
[16][111] |
- |
- |
9.5–10.8 * |
[98] |
Reconsitituted beans 1 |
- |
11.8–12.7 |
[113] |
PGG Tic |
10.8 |
9.8–10.5 |
[22][108] |
Spec Tic |
9.2 |
8.3 |
[108] |
South Tic |
12.0 |
10.6 |
[108] |
Broad |
8.8 |
8.5 |
[108] |
Merlin |
- |
11.6 # |
[110] |
Olga |
- |
10.1 # |
[110] |
Albus |
- |
8.1 # |
[110] |
Amulet |
- |
7.9 *–12.2 # |
[99][110] |
Kasztelan |
- |
11.9 # |
[110] |
Kontu |
12.4 |
|
[35] |
Ukko |
11.9 |
- |
[35] |
3.2. Amino Acid Digestibility
The ileal AA digestibility AAs in faba beans is generally lower compared to those reported for SBM
[75][115]. However, as can be seen in
Table 16, the digestibility of most AAs is moderately high. The digestibility is highest for arginine (0.81–0.91) and lowest for cysteine (0.47–0.77).
Table 16. Apparent 1/standardised 2 ileal digestibility coefficient of amino acids in faba bean for broilers.
Amino Acid |
[22] 1 |
[35] 1,3 |
[41] 1 |
[108] 1,4 |
[109] 2,5 |
[110] 1 |
Essential |
|
|
|
|
|
|
Arginine |
0.91 |
0.90 |
0.81 |
0.90 |
0.88 |
0.91 |
Histidine |
0.70 |
0.82 |
0.72 |
0.72 |
0.79 |
0.85 |
Isoleucine |
0.85 |
0.82 |
0.68 |
0.83 |
0.77 |
0.84 |
Leucine |
0.85 |
0.85 |
0.70 |
0.84 |
0.80 |
0.84 |
Lysine |
0.91 |
0.88 |
0.76 |
0.89 |
0.83 |
0.90 |
Methionine |
0.86 |
0.75 |
0.63 |
0.81 |
0.63 |
0.90 |
Phenylalanine |
0.86 |
0.80 |
0.72 |
0.88 |
0.80 |
0.85 |
Threonine |
0.84 |
0.79 |
0.68 |
0.77 |
0.72 |
0.81 |
Tryptophan |
na |
na |
na |
na |
0.80 |
na |
Valine |
0.83 |
0.85 |
0.68 |
0.81 |
0.75 |
0.85 |
Non-essential |
|
|
|
|
|
|
Alanine |
0.89 |
0.86 |
0.71 |
0.86 |
0.80 |
0.86 |
Aspartic acid |
0.86 |
0.84 |
0.71 |
0.87 |
0.80 |
0.86 |
Cysteine |
0.63 |
0.49 |
0.58 |
0.56 |
0.47 |
0.77 |
Glycine |
0.81 |
0.77 |
0.67 |
0.76 |
0.65 |
0.82 |
Glutamic acid |
0.90 |
0.87 |
0.75 |
0.88 |
0.87 |
0.90 |
Proline |
0.71 |
0.75 |
na |
0.54 |
0.75 |
0.83 |
Serine |
0.86 |
0.81 |
0.69 |
0.79 |
0.78 |
0.85 |
Tyrosine |
0.84 |
0.76 |
0.70 |
0.80 |
0.77 |
0.81 |
3.3. Feeding Trials
Perez-Maldonado
[16] studied the inclusion level of 250 g/kg of grain legumes (faba beans, chickpeas, sweet lupins and field peas) on the productive performance of laying hens over a period of 40 weeks and reported a reduced feed intake, hen-day egg production, egg weight and egg mass, and inferior feed conversion efficiency in birds fed faba bean (cv. Fiord) diets compared to those fed other grain legume-based diets. Alagawany et al.
[116] studied five faba bean replacement levels (0, 25, 50, 75 and 100%) as a substitute for SBM for laying hens and reported that SBM can be replaced with faba beans at levels less than 50% in laying hen diets. In the same study, the intakes of feed, protein and AME were decreased as the level of faba bean increased and the egg laying rate, egg output and feed efficiency were the lowest in hens receiving diets at 75 and 100% substitution.
Farrell et al.
[39] examined different inclusion levels of faba bean for broiler chickens and recommended an inclusion level of 200 g/kg in broiler diets. Similarly, Nalle et al.
[67] observed that faba beans can be included up to 200 g/kg in broiler diets without any detrimental effects on performance. Koivunen et al.
[114] studied four inclusion levels (0, 80, 160 and 240 g/kg) of faba beans for broilers and concluded that a 160 g/kg faba bean can be safely used in broiler diets. These findings are in agreement with the results of Gous
[111] and Ivarsson and Wall
[117] who did not find any adverse effect of pelleted broiler diets with 200–250 g/kg faba bean on the growth performance of broilers. In contrast, the same study also reported a reduced feed intake and body weight in broilers fed the mash diet with the same inclusion level of faba beans, which suggests that the optimum faba bean inclusion level depends on the feed form. It is evident that the negative effect of feeding faba beans on the growth performance of poultry in the early studies is due to the high concentration of antinutrients in faba beans. However, with the development of plant breeding techniques, there are cultivars with zero-tannin or low vicine and convicine concentrations
[109][112][118]. It has been reported that inclusions of 150, 300, 400–450 g/kg of zero-tannin faba bean cultivars is possible for broiler starter, grower and finisher, respectively
[112][118].
Time of planting and harvesting faba beans, especially in the tropics, may influence the seed quality and its digestibility and consequently the growth performance in poultry. Smit et al.
[109] studied the effect of the early or late planting and harvesting of two zero-tannin cultivars (Snowbird and Snowdrop) and a low-vicine and -convicine cultivar (Fabelle) on the nutrient digestibility, and reported that late planting and harvesting increased the digestibility of gross energy, protein and AA when compared to early-planting and -harvesting cultivars, regardless of increased proportions of frost-damaged beans in the late-planting and -harvesting cultivars. However, a subsequent study
[118] did not find any negative effect on the growth performance of broilers fed low-quality (frost-damaged or immature) faba beans (150, 300, 450 g/kg for broiler starter, grower and finisher, respectively) when compared to those fed the high-quality seeds.
4. Chickpeas
Chickpeas are grouped into two types, namely ‘Desi’ and Kabuli’ varieties, based on seed size, colour and the thickness and shape of the seed coat. Desi type chickpeas are of Indian origin whereas Kabuli chickpeas are of Mediterranean, North African and West Asian origins. According to Nalle
[2], Desi types produce smaller seeds, generally 400 or more seeds per 100 g. The seeds have a thick, irregular-shaped seed coat which can range in colour from light tan to black. Kabuli varieties (also referred to as garbanzo beans) produce larger seeds that have a thin seed coat with colours that range from white to a pale cream-coloured tan.
The crude protein content of chickpeas is moderate, ranging between 182 and 270 g/kg DM as summarised in
Table 17. The starch content ranges between 310 and 535 g/kg DM. There are differences between the two varieties, with Desi varieties containing less starch (364 vs. 411 g/kg
[119]) and more fibre (90 vs. 60 g/kg
[120]) than the Kabuli varieties. The lipids in chickpeas comprise mostly of polyunsaturated fatty acid, with linoleic and oleic acids as the primary constituents
[119]. The moderate content of fat (42–156 g/kg) and high starch content make chickpeas a good source of available energy for poultry. Chickpea is richer in phosphorous and calcium when compared to other grain legumes.
Table 17. Nutrient composition (g/kg, dry mater basis) of chickpeas.
The AA composition of chickpeas is presented in
Table 18. Glutamic acid is found in the highest concentrations in chickpeas, followed by aspartic acid and arginine. Chickpeas is a good source of lysine, but deficient in methionine and cysteine. A tryptophan content of 1.8 g/kg (as received basis) was reported in chickpeas
[132]. As suggested by Chiaiese et al.
[139], the use of transgenic techniques would help overcome the deficiency of these limited AAs.
4.1. Apparent Metabolisable Energy
Published data on the AME of chickpeas are scant. According to Feedipedia
[47], the AME of Desi chickpeas was 12.7 MJ/kg DM. However, INRA feed tables
[140] reported an AME
n of 14.5 MJ/kg DM for chickpea for broilers. Using the European table of energy values for poultry feedstuffs
[141], Viveros et al.
[120] estimated the AME of Kabuli and Desi chickpeas to be 12.6 and 10.5 MJ/kg DM, respectively. The lower AME of the Desi type was attributed to its higher fibre content compared to Kabuli types (90–112 vs. 33–60 g/kg)
[120][142]. The AME of chickpeas for other poultry species has also been reported. The AME of chickpeas was determined to be 10.5 MJ/kg for laying hens
[16], 14.8 MJ/kg DM for adult roosters
[140] and 12.8 MJ/kg for broiler turkeys (cv. Burnas;
[128]).
Table 18. Amino acid content (g/kg, dry matter basis) of chickpeas.
Amino Acid |
References |
[16] 1 |
[41] |
[120] 2 |
[128][129] 3 |
[130] 4 |
[131] |
[137] 5 |
[143] |
Essential |
|
|
|
|
|
|
|
|
Arginine |
17.6 |
25.6 |
22.8 |
20.1 |
19.2 |
na |
19.9 |
14.4 |
Histidine |
5.1 |
6.9 |
7.9 |
na |
6.5 |
6.2 |
5.4 |
4.4 |
Isoleucine |
8.5 |
11.4 |
10.3 |
9.1 |
9.7 |
10.4 |
6.7 |
6.6 |
Leucine |
14.9 |
18.3 |
18.5 |
19.3 |
17.6 |
17.4 |
16.3 |
12.0 |
Lysine |
11.8 |
15.2 |
14.7 |
18.8 |
16.4 |
14.5 |
15.1 |
9.4 |
Methionine |
2.6 |
3.0 |
3.2 |
na |
1.7 |
1.9 |
3.1 |
Na |
Phenylalanine |
11.4 |
13.8 |
15.0 |
12.5 |
11.0 |
13.1 |
11.5 |
10.3 |
Threonine |
7.3 |
8.8 |
10.0 |
10.2 |
8.0 |
8.8 |
8.2 |
8.3 |
Tryptophan |
na |
na |
Na |
na |
3.0 |
1.6 |
na |
na |
Valine |
8.9 |
11.5 |
10.5 |
9.6 |
10.7 |
10.2 |
7.4 |
8.8 |
Non-essential |
|
|
|
|
|
|
|
|
Alanine |
8.2 |
10.2 |
10.2 |
14.1 |
na |
na |
na |
6.8 |
Aspartic acid |
22.0 |
26.8 |
26.3 |
29.0 |
na |
na |
na |
15.7 |
Cysteine |
3.3 |
3.5 |
Na |
na |
4.1 |
2.1 |
3.7 |
Na |
Glycine |
7.9 |
9.3 |
9.6 |
9.2 |
na |
na |
na |
7.9 |
Glutamic acid |
31.3 |
38.9 |
49.1 |
49.7 |
na |
na |
na |
24.9 |
Proline |
8.1 |
na |
Na |
na |
6.4 |
na |
na |
12.3 |
Serine |
10.2 |
13.2 |
13.0 |
12.5 |
na |
na |
na |
9.4 |
Tyrosine |
5.8 |
6.6 |
7.6 |
6.3 |
6.9 |
6.2 |
4.4 |
7.9 |
4.2. Amino Acid Digestibility
Only one published report is available on the digestibility of the AAs of chickpeas. Ravindran et al.
[41] reported that the apparent ileal digestibility coefficient of AAs ranged from 0.58 for cysteine to 0.84 for arginine (
Table 19). The poor digestibility of cysteine is probably related to the low concentration (2.1–4.1 g/kg;
Table 18) of this AA in chickpeas. Ravindran et al.
[132] reported an ileal digestibility coefficient of 0.71 for tryptophan in chickpeas.
Table 19. Apparent ileal amino acid digestibility coefficients in chickpeas for broilers.
Amino Acid |
Digestibility Coefficient |
Essential |
|
Arginine |
0.84 |
Histidine |
0.77 |
Isoleucine |
0.70 |
Leucine |
0.70 |
Lysine |
0.76 |
Methionine |
0.72 |
Phenylalanine |
0.78 |
Threonine |
0.70 |
Valine |
0.73 |
Non-essential |
|
Alanine |
0.73 |
Aspartic acid |
0.73 |
Cysteine |
0.58 |
Glycine |
0.68 |
Glutamic acid |
0.78 |
Serine |
0.74 |
Tyrosine |
0.72 |
4.3. Feeding Trials
Viveros et al.
[120] demonstrated that the dietary inclusion of chickpea, varieties Kabuli (0, 150, 300 and 450 g/kg) and Desi (75 and 150 g/kg), linearly reduced the performance of growing chickens and increased the relative weight and length of the intestinal tract in 28-day old broilers. They also found that the inclusion of Kabuli chickpea resulted in the lower digestibility of starch and protein, intestinal enzyme (α-amylase and trypsin) activities and AME
n compared to those fed the control diet. However, the performance of birds was improved by the autoclaving of chickpeas. Farrell et al.
[39] studied different inclusion levels (0, 120, 180, 240 and 360 g/kg) of grain legumes (field peas, chickpeas, faba beans and sweet lupins) in broilers and reported that overall, weight gain and feed conversion ratio (FCR) were inferior in broiler starters fed chickpeas (cv. Amethyst) compared to those fed field peas and faba beans. The birds fed the chickpea diets had lower digesta viscosity when compared to those fed the lupins, and the heaviest weight of the pancreas when compared to those fed other grain legumes. However, the growth performance was not influenced by different chickpea inclusions in broiler finishers. It was concluded that the maximum inclusion level of chickpeas in broiler starter and finisher diets was 100 g/kg. Similarly, Algam et al.
[124] suggested an inclusion of 100 g/kg chickpeas for broilers. Christodoulou et al.
[130] studied three chickpea inclusion levels (0, 120 and 240 g/kg) for broilers and reported that feeding the diet with 240 g/kg chickpeas adversely affected the performance and carcass yield of broiler chickens. However, the same study found a similar performance between the birds fed the diet with 0 and 120 g/kg chickpeas and recommended an inclusion of 120 g/kg chickpeas for broilers. A recent study reported a negative effect of 50% replacement of chickpeas (315–344 g/kg) for SBM on intestinal histomorphology and microbial populations in broilers
[144]. The inclusion of raw chickpeas was observed to induce disturbances in metabolism by means of the shortening and thickening of intestinal villi and in intestinal structure in the same study. Nevertheless, an inclusion of 200 g/kg chickpea inclusion has been suggested by Bampidis and Christodoulou
[145] and Ciurescu et al.
[129].
Perez-Maldonado et al.
[16] concluded from their experiments with laying hens that good production can be achieved when the inclusion rate of chickpeas was 250 g/kg. However, it was suggested that it is safer to use lower inclusion levels because of pancreatic enlargement in hens fed chickpea diets, possibly due to the presence of trypsin and chymotrypsin inhibitors. Feeding chickpeas for other poultry species has also been reported. According to Ciurescu et al.
[128], young turkeys can be fed 240 g/kg chickpeas as an alternative protein source. Sengül and Calisar
[126], did not find any negative effect of feeding 200 and 400 g/kg chickpea on the production performance of laying quails.