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Effect of the inclusion of discarded red bean (Phaseolus vulgaris L.) meal on performance and egg quality of laying hens

M A Paz y Miño, I F Suazo, R Castillo1, R Sanchez, F J Amaya and Y Martínez

Poultry Research and Teaching Center, Agricultural Science and Production Department, Zamorano Pan-American Agricultural School, Valle de Yeguare, San Antonio de Oriente, Honduras
1 Agricultural Science and Production Department, Zamorano Pan-American Agricultural School, Valle de Yeguare, San Antonio de Oriente, Honduras
ymartinez@zamorano.edu

Abstract

The aim of this experiment was to evaluate the inclusion of discarded red bean (Phaseolus vulgaris L.) meal on performance and egg quality of laying hens. A total of 80 hens of the Hy-Line White® genetic line were randomly distributed for 10 weeks in two treatments, eight replicates per treatment and five birds per replicate. The dietary treatments consisted of a control diet (CTL) and the inclusion of 15% discarded red bean meal (RB). The proposed experimental group (15% discarded red bean meal) improved (P<0.05) laying intensity, egg weight and mass conversion, although it provoked a higher percentage of dirty eggs (P<0.05). Likewise, RB increased (P<0.05) the eggshell thickness, however it decreased (P<0.05) the egg yolk pigmentation. Also, feed intake, albumen height, Haugh unit and shell break strength did not change due to treatment effect (P>0.05). It is recommended, the inclusion of 15% discarded red bean meal to partially replace

Key word: alternative ingredient, economic benefit, final product, hens, productivity


Introduction

Currently, the high price of the main raw materials to produce animal feed, due to inflation, speculation, their export to China, and the war in Ukraine, have caused low economic profitability for many poultry companies (mainly small and medium enterprises) (Williams et al. al 2022). The gap between local supply and demand for these traditional ingredients is expected to widen in the coming decades (Mallory 2021). Thus, the poultry industry is constantly seeking to find available and affordable alternative feeds that can partially or totally replace corn and soybean meal, without affecting performance and with a positive economic impact (Kleyn and Ciacciariello 2021).

In this sense, beans (Phaseolus vulgaris L.) constitute one of the most traditional crops in Central America, which is part of the basic grains of the region (Beaver et al 2022). According to CEPAL (Economic Commission for Latin America and the Caribbean 2013) most of its production is developed by small producers, being an essential food within the circular economy in the communities. Likewise, in the classification of beans as seed, the discarding them for different non-phytopathological reasons is common, however, their use in animal feed is little studied (Arija et al 2006).

Due to its chemical composition, discarded beans could be a viable alternative to lower production costs in poultry diets (Soysal 2021). Other experiments have used beans under different treatments (precooked and soaked) with inconclusive results (Carew and Gernat 2006 and Okonkwo et al 2021), likewise, the use of raw broad beans (without previous treatment) in poultry diets is not recommended, because theses seeds have secondary metabolites, which in excess can provoke symptoms related to antinutritional factors, such as trypsin and chymotrypsin inhibitors (Lamz et al 2021).

The new bean varieties developed at the Zamorano Pan-American Agricultural School have greater resistance to diseases and are more adapted to the production systems of the region (Durón and Amador 2022). Also, other previous studies found that apparently these genetic processes can modify the quantification of secondary metabolites, which allows the use of discarded beans without treatment and in a higher inclusion in the diet (Wenham 2021). Thus, the objective of this study was to evaluate the dietary inclusion of discarded red bean (Phaseolus vulgaris L.) meal on performance and egg quality of Hy-Line White® laying hens.


Materials and methods

Experimental location

This study was conducted at the Poultry Research and Teaching Center, Zamorano Pan-American Agricultural School, located in Valle de Yegüare, municipality of San Antonio de Oriente, department of Francisco Morazán, 32 km from Tegucigalpa, Honduras. The experimental unit has a height of 800 meters above sea level and an average temperature of 26 °C.

Chemical composition of the discarded red bean

The discarded Amadeus 77 red bean was purchased at the seed processing plant of the Zamorano Pan-American Agricultural School. Then, dry matter, crude protein, ashes, N, Ca, Mg, K, Cu, Fe, Mn, and Zn were determined according to AOAC 2001.11. (2006) and the P available by the molybdenum blue colorimetric method. Table 1 shows the chemical composition of the discarded red bean.

Table 1. Chemical composition of the discarded red bean meal

Items

Mean

Standard
Deviation (±)

Coefficient of
variation (%)

Dry matter (%)

90.8

0.624

0.687

Ashes (%)

6.04

0.236

3.907

Crude protein (%)

22.2

0.736

3.316

N (%)

3.55

0.117

3.295

Available P (%)

0.37

0.005

1.351

K (%)

1.68

0.037

2.202

Ca (%)

0.06

0.006

10

Mg (%)

0.13

0.006

4.615

Cu (mg/kg)

8.67

0.577

6.655

Fe (mg/kg)

59

0.999

1.693

Mn (mg/kg)

17.67

0.577

3.265

Zn (mg/kg)

40.3

2.081

5.159

Animals, experimental design, and treatments

A total of 80 35-week-old Hy-Line White® laying hens were allocated in a completely randomized design for 10 weeks, with two treatments, eight replicates per treatment, and five birds per replicate. The dietary treatments consisted of a control diet (CTL) and the inclusion of 15% discarded red bean meal (RB15). Table 2 shows the composition of the experimental diets.

Table 2. Experimental diets for Hy-line White laying hens (35-45 weeks)

Ingredients

Control

RB15

Yellow corn meal

49.66

38.89

Soymeal

31.28

26.12

African palm oil

5.69

6.55

Discarded red bean meal

0

15

Premix1

0.35

0.35

Exogenous enzymes2

0.05

0.05

Choline

0.05

0.05

Mycofix plus 5.0

0.12

0.12

Coarse calcium carbonate

6.70

6.69

Fine calcium carbonate

3.61

3.61

Monocalcium phosphate

1.73

1.77

Sodium bicarbonate

0.28

0.28

Common salt

0.23

0.23

DL-methionine

0.251

0.29

L-threonine

0.01

0

Cost (USD/t)

533.46

520.15

Nutritional contributions

Metabolizable energy (kcal/kg)

2800

2800

Crude protein (%)

17.6

17.6

Ca

4.1

4.1

P available

0.48

0.48

Digestible lysine

0.85

0.85

Digestible methionine and cystine

0.74

0.74

Digestible threonine

0.6

0.6

1 Vitamin and mineral premix: vitamin A, 1000 IU/kg; vitamin D3, 2000 IU/kg; vitamin E, 30 IU/kg; vitamin K3, 2 mg/kg; vitamin B1, 1 mg/kg; vitamin B2, 6 mg/kg; vitamin B6, 3.5 mg/kg; vitamin B12, 18 mg/kg; niacin, 60 mg/kg; pantothenic acid, 10 mg/kg; biotin, 10mg/kg; folic acid, 0.75 mg/kg; choline, 250 mg/kg; iron, 50 mg/kg; copper, 10mg/kg; zinc, 70 mg/kg; manganese, 70mg/kg; selenium, 0.30 mg/kg; Iodine, 1 mg/kg.2 Lumis Lbzyme X50® multienzyme complex is composed of xylanase (25000 U/g), mannanase (250 IU/g), beta-glucanase (2500 IU/g), cellulase (400000 U/g), pectinase (80 IU/g), galactosidase (100 U/g), protease, (2500 Hut/g), amylase (60000 U/g) and phytases (15000 FTU/g)

Experimental conditions

The laying hens were housed in a 400 m2 commercial shed, in 61 × 36 cm cages, with ceiling fans and an artificial lighting system. Water ad-libitum in two nipple drinkers per cage was offered and feed intake to 110 g/day/bird in linear feeders was restricted. 16 hours of light each day was supplied, and no veterinary attention during the experimental stage was used. For the adaptation to the new diets, a pre-experimental phase of 14 days was provided.

Growth performance

To determine the laying intensity, the total production of eggs/week/treatment was considered; one egg/day/bird housed was assumed to be 100%. To determine egg weight, 30 eggs were collected weekly for each treatment, between 8:30 am and 9:30 am. The eggs were weighed on an OHAUS® digital technical scale (New Jersey, USA), with a precision of ± 0.1 g. The feed intake was determined three times per week according to the offer and rejection method. Also, dirty eggs daily were counted to determine their percentage considering egg production. Mass conversion (MC) was calculated from the formula:

External and internal egg quality

To determine the external and internal egg quality, 30 eggs for each experimental treatment (two eggs for each replicate) were collected weekly. For egg quality, each egg constitutes an experimental unit. All the eggs were collected at the same time and were transferred to the egg quality laboratory within the Research and Teaching Center of the Zamorano University. The external and internal quality of the eggs were analyzed on the same day of collection using an automatic TSS EggQuality analyzer (York, England) and Eggware v4x software. Egg weight was determined on an OHAUS® digital scale (New Jersey, USA) with an accuracy of ± 0.1 g. The eggshell breaking strength was analyzed at the mid pole using a QC shell and packing force analyzer. For the eggshell thickness (mid pole) a micrometer with an accuracy of ± 0.001 mm was used.

For internal egg quality, the albumen height was measured using a QHC® height indicator with an accuracy of ± 0.01 mm (automatic TSS EggQuality analyzer, York, England). The Haugh unit was calculated with the formula HU=100* log (H + 1.7W0.37 + 7.6); where HU is the Haugh unit, H is albumen height and W is egg weight. The yolk color was evaluated using a CCC® electronic colorimeter, which considers the Roche scale of 15 colors.

Statistical analysis

Descriptive statistic for the chemical composition of discarded red bean meal were performed. Data was analyzed by T Students test for two independent samples. Dirty eggs were determined by comparison of proportions. Values of P <0.05 were taken to indicate significant differences. The SPSS 23.0.1.2014 program (SPSS Inc., Chicago, IL, USA) was used for statistical analyzes.


Results

Table 3 shows the effect of including RB15 in the diet of Hy-Line White® laying hens. This treatment (15% discarded beans) improved (P<0.05) laying intensity, egg weight and mass conversion, although it increased (P<0.05) dirty eggs, without changes in feed intake (P>0.05).

Table 3. Effect of the inclusion of discarded red bean on performance of laying hens

Indicators

Experimental treatments

SEM±

p

Control

RB15

Laying intensity (%)

90.21

93.32

1.189

0.015

Egg weight (g)

56.54

60.07

0.331

0.001

Feed intake (g/bird/day)

106

106.2

0.334

0.678

Mass conversion (kg/kg)

2.09

2

0.016

0.048

Dirty eggs (%)

3.7

6.52

0.805

0.050

Table 4 shows the external and internal egg quality when using 15% discarded red bean meal without physical or chemical treatment on laying hen diets. At weeks 40 and 45, the experimental group with discarded red bean meal increased (P<0.05) notably the eggshell thickness, (P<0.05). The other external and internal quality indicators of the egg did not change due to the effect of the experimental diets (P>0.05).

Table 4. Effect of discard red bean on the external and internal egg quality of laying hens

Indicators

Experimental treatments

SEM±

p

Control

RB15

Week 40

Egg weight (g)

60.65

60.59

0.59

0. 23

Albumen height (mm)

10.46

10.74

0.16

0.21

Haugh unit

101.33

102.67

0.54

0.09

Shell break strength (kg F)

5627.16

5607.55

13.1

0.1

Eggshell thickness (mm)

0.376

0.448

0.01

0.03

Yolk color

3.31

2.18

0.01

<0.001

Week 45

Egg weight (g)

58.65

59.09

0.550

0.65

Albumen height (mm)

10.48

10.50

0.169

0.91

Haugh unit

101.36

102.42

0.572

0.28

Shell break strength (kg F)

5627.17

5704.53

20.49

0.58

Eggshell thickness (mm)

0.38

0.452

0.004

0.01

Yolk color

2.9

1.12

0.116

<0.001


Discussion

One of the aims of this study was to evaluate whether the inclusion of 15% discard bean meal without previous treatment could influence the productivity of laying hens. Interestingly, the inclusion of discard beans promoted laying intensity and egg weight, being similar to what is mentioned in the Hy-line White® management manual (Hy-line International 2022). Apparently, the exogenous enzymes used On top could favor the availability of nutrients in the diet with discarded beans, which causes a better assimilation of these (Jabbar et al 2021), this was verified by the increase in laying intensity by 3.11% and egg weight by 3.53 g (Table 3). It is known that enzymes vary in specificity, some are highly substrate specific, while others can bind to a wide range of substrates and catalyze (Guo et al 2022). Thus, Jaroni et al (1999) informed that the egg weight increased significantly with the inclusion of exogenous enzymes to a diet based on wheat, however, another study that added protease enzymes in the diet based on corn and soybean with a deficit of 4 and 10% in protein did not affect this productive parameter (Quispe 2005). Other studies are necessary to elucidate the relationship between the use of exogenous enzymes and substrates in diets rich in discarded red bean meal.

Also, the amino acids present in the discarded red bean meal could positively influence the intensity of laying and the egg weight (Table 3). In this sense, Wu et al (1996) found a high concentration of arginine and branched-chain amino acids in raw beans (Phaseolus vulgaris L.), and these amino acids were not controlled in the diets of this experiment (Table 2), thus it seems that diets with red bean meal had a higher concentration of these (Table 2). Arginine is known to be involved in the development of musculoskeletal health, antioxidant capacity, damaging lipids, and fat accumulation in poultry (Balnave and Barke 2002), also, branched chain amino acids (leucine, isoleucine, and valine) intervenes on growth, productivity, immunity, and intestinal health of poultry (Kim et al 2022).

Another factor that could influence these results is the bean variety (Amadeus 77). Genetic improvement plays a very important role in obtaining seeds with better characteristics, such as early maturation, high yield, nutritional quality of the grain, and resistance to insects and diseases (Suárez et al 2020). Also, it has been described that this genetic improvement provokes changes in the chemical and phytochemical composition (Aquino-Bolaños et al 2021). These modifications were probably expressed as a decrease in the level of antinutrients (Herrera et al 2021). Apparently, genetically improved discard bean meal (Amadeus 77) has a lower concentration of trypsin and chymotrypsin inhibitors, normally found in concentrations of 39 U/g and 22 U/g, respectively (Wu and Whitaker, 1990). According to Kowalska et al (2021) the egg weight decreases when legume seeds are used in the diet as protein sources, due to the high concentration of tannins that decreases the absorption of sulfur amino acids, however, the present study showed different results, apparently this variety (Amadeus 77) has a low concentration of this polyphenolic compound (tannins), this was able to improve the productive performance in laying hens. However, more research is needed to confirm this hypothesis.

On the other hand, feed intake did not change because of the diets (Table 3). Apparently, the crude fiber content of the discarded beans did not influence this productive indicator, because the change in voluntary intake of feed may be related to the increase in dietary fiber in the diet, which increases gastrointestinal transit (Wang et al 2021), also, the fibrous content of bean fiber (6.1%) is similar to that of soymeal (5.9%) (El-Wahab et al 2021). Thus, the mass conversion that depends on the number of eggs produced (51%), feed intake (31%), and egg weight (18%) (Zelaya et al 2022), showed that the use of 15% of discarded red bean meal improved the productive efficiency of laying hens, demonstrated by the lower mass conversion (Table 3). Moreover, the use of discarded red bean meal increased the percentage of dirty eggs, by 2.82% (Table 3). This could occur due to the size of the egg, which in its journey through the oviduct channel drags a greater amount of feces contained in the cloaca and in some cases can cause small bleeding wounds at this level (Soler et al 2022).

Also, albumen height does not change due to experimental treatments, albumen height is a moderately heritable trait (Rath et al 2015). This result shows that beans included up to 15% in the diet did not influence egg protein synthesis, because lower protein availability has a direct impact on albumen height (Castiblanco et al 2021). Likewise, no significant differences were observed in the Haugh units. According to the classification provided by the USDA (2000), Haugh units above 72 are a sign of good egg quality. Thus, both treatments have excellent quality for their commercialization (Martínez et al 2021a).

The eggshell thickness ensures a better egg resistance, which has a favorable effect in reducing the number of broken eggs and their longer time on the shelf. Shell quality is important to ensure the profitability and sustainability of egg production (He et al 2022). Thus, the use of discard beans increased the eggshell thickness in both tests of external egg quality (Table 4). However, Laudadio and Tufarelli (2010) found no changes in the external quality of the egg when totally substituting soymeal for fava bean (Vicia faba var. minor) meal. According to Roberts (2004), laying hens are very susceptible to the availability of calcium for egg formation, thus shell thickness can vary due to the composition of the diet and the concentration of secondary metabolites found in it. Thus, the bean variety (Amadeus 77) could influence this result, also to the use of exogenous enzymes that provoke the greatest release of available calcium and phosphorus.

On the other hand, the inclusion with 15% of discarded red bean meal replaced 10.77% of cornmeal in the diet (Table 2), which provoked a drastic decrease in the yolk color, due to the fact that the corn yellow is rich in zeaxanthin and other pigments (Kljab et al 2021). One of the strategies is the use of natural or artificial pigments in the diets to correct the color of the yolk according to the market (Martínez et al 2021b).


Conclusions


References

AOAC 2006 Official Methods of Analysis of AOAC. Edition 18.; Association of Official Analytical Chemists Gaithersburg MD USA.

Aquino E N Garzón A K Alba J E Chávez J L Vera A M Carrillo J C and Santos M A 2021 Physicochemical characterization and functional potential of Phaseolus vulgaris L. and Phaseolus coccineus L. landrace green beans Agronomy 11(4): 803.

Arija I Centeno C Viveros A Brenes A Marzo F Illera J C and Silvan G 2006 Nutritional evaluation of raw and extruded kidney bean (Phaseolus vulgaris L. var. Pinto) in chicken diets Poultry Science 85(4): 635-644.

Balnave D and Barke J 2002 Re-evaluation of the classical dietary arginine: lysine interaction for modern poultry diets: a review World's Poultry Science Journal 58(3): 275-289.

Balnave D and Barke J 2002 Re-evaluation of the classical dietary arginine: lysine interaction for modern poultry diets: a review World's Poultry Science Journal 58(3): 275-289.

Beaver J S Martínez H Godoy G Estevez C Porch T G and Rosas J C 2022 Breeding for resistance and integrated management of web blight in common bean Crop Science 62(1): 20-35.

Bethlem I V Lima R A and Lima L 2022 The impact of the USDA soybean crop condition reports on CBOT futures prices Revista de Economia e Sociologia Rural 61.

Carew L B and Gernat A G 2006 Use of velvet beans, Mucuna spp., as a feed ingredient for poultry: a review World's Poultry Science Journal 62(1) 131-144.

Castiblanco F Paz P E Valdivié M and Martínez Y 2021 Effect of inclusion levels of dry distillery grains with solubles (DDGS) on productivity and egg quality of Hy-Line Brown® laying hens Cuban Journal of Agricultural Science 55(4): 391-402.

CEPAL 2013 Impactos potenciales del cambio climático sobre los granos básicos en Centroamérica. https://repositorio.cepal.org/handle/11362/27171.

Durón D J and Amador V E 2022 Efecto del fósforo acumulado en suelos en la producción de maíz Tuxpeño y frijol Amadeus-77 en Zamorano Dissertation Zamorano: Escuela Agrícola Panamericana. https://bdigital.zamorano.edu/handle/11036/7204

El-Wahab AA Wilke V Grone R and Visscher C 2021 Nutrient digestibility of a vegetarian diet with or without the supplementation of feather meal and either corn meal, fermented rye or rye and its effect on fecal quality in dogs Animals 11(2): 496.

Guo X An Y Jiang L Zhang J Lu F Liu F 2022 The discovery and enzymatic characterization of a novel AA10 LPMO fromBacillus amyloliquefaciens with dual substrate specificity. International Journal of Biological Macromolecules, 203: 457-465.

He S Lin J Jin Q Ma X Liu Z Chen H and Wu Z 2022 The relationship between animal welfare and farm profitability in cage and free-range housing systems for laying hens in China Animals 12(16): 2090.

Herrera M D Reynoso-Camacho R Melero-Meraz V Guzmán-Maldonado S H and Acosta-Gallegos J A 2021 Impact of soil moisture on common bean (Phaseolus vulgaris L.) phytochemicals Journal of Food Composition and Analysis 99 103883.

Hy-line International 2022 Management Guide. https://www.hyline.com/filesimages/Hy-Line-Products/Hy-Line-Product-PDFs/W-80/80%20COM%20ENG.pdf

Jabbar A Tahir M Alhidary IA Abdelrahman MA Albadani H Khan RU and Tufarelli V 2021 Impact of microbial protease enzyme and dietary crude protein levels on growth and nutrients digestibility in broilers over 15–28 days Animals 11(9): 2499.

Jaroni D Scheideler S E Beck M M and Wyatt C 1999 The effect of dietary wheat middlings and enzyme supplementation II: apparent nutrient digestibility, digestive tract size, gut viscosity, and gut morphology in two strains of leghorn hens Poultry Science 78(12): 1664-1674.

Kim W K Singh A K Wang J and Applegate T 2022 Functional role of branched chain amino acids in poultry: a review. Poultry Science 101715.

Kleyn F J and Ciacciariello M 2021 Future demands of the poultry industry: will we meet our commitments sustainably in developed and developing economies? World's Poultry Science Journal 77(2) 267-278.

Kljak K Duvnjak M Bedeković D Kiš G Janječić Z and Grbeša D 2021 Commercial corn hybrids as a single source of dietary carotenoids: Effect on egg yolk carotenoid profile and pigmentation Sustainability 13(21): 12287.

Kowalska E Kucharska-Gaca J Kuźniacka J Lewko L Gornowicz E Biesek J Adamski M 2021 Egg quality depending on the diet with different sources of protein and age of the hens Scientific Reports 11(1): 1-11.

Lamz A Cázares Z Jiménez J C Molina F J Sepúlveda D R Rios C y Olivas G I 2021 Cocción tradicional con especias de Phaseolus vulgaris L. y su efecto antinutricional e inhibición bacteriana Biotecnia 62–69.

Mallory ML 2021 Impact of COVID‐19 on medium‐term export prospects for soybeans, corn, beef, pork, and poultry Applied Economic Perspectives and Policy 43(1): 292-303.

Martínez Y Orozco C E Montellano R M Valdivié M and Parrado C A 2021b Use of achiote (Bixa orellana L.) seed powder as pigment of the egg yolk of laying hens. Journal of Applied Poultry Research 30(2): 100154.

Martínez Y Soliz N D Bejarano M A Paz P and Valdivie M 2021a Effect of storage duration and temperature on daily changes in external and internal egg quality of eggs from Dekalb White® laying hens European Poultry Science 85: 1-14.

Okonkwo I F NwosuS. C Nwankwo C A Isaac U C Okafor E C and Okonkwo J C 2021 Effect of processing method of kidney beans (Phaseolus vulgaris) on carcass quality, organ weight and organoleptic properties of broilerInternational Journal of Engineering Research & Science 7(9).

Quispe L L 2005 Evaluación de proteasa (Poultry Grow 250™) en dietas de maíz y harina de soya en ponedoras Leghorn Blanco (H&N Nick Chick) Dissertation Zamorano: Escuela Agrícola Panamericana https://bdigital.zamorano.edu/handle/11036/5254

Rath P K Mishra P K Mallick B K and Behura N C 2015 Evaluation of different egg quality traits and interpretation of their mode of inheritance in White Leghorns Veterinary world 8(4): 449.

Roberts J R 2004 Factors affecting egg internal quality and egg shell quality in laying hens. The Journal of Poultry Science 41(3): 161-177.

Soler R Mínguez C Ibáñez C and Bueso J 2022 egg size and quality of hens housed in three different group sizes. Journal of Applied Animal Research 50(1): 598-602.

Soysal S 2021 Effects of different doses of poultry manure application on yield components and yield of different faba bean (Vicia faba L.) varieties Legume Research-An International Journal 44(11): 1338-1342.

Suárez J C Polanía J A Contreras A T Rodríguez L Machado L Ordoñez C and Rao I M 2020 Adaptation of common bean lines to high temperature conditions: genotypic differences in phenological and agronomic performance Euphytica 216(2): 1-20.

Wang J Kong F and Kim W K 2021 Effect of almond hulls on the performance, egg quality, nutrient digestibility, and body composition of laying hens Poultry Science 100(9): 101286.

Wenham G M 2021 Estrategias nutricionales para sustituir totalmente la harina de maíz en dietas de gallinas ponedoras Dissertation Zamorano: Escuela Agrícola Panamericana. http://hdl.handle.net/11036/7156

Wu C and Whitaker J R 1990 Purification and partial characterization of four trypsin/chymotrypsin inhibitors from red kidney beans (Phaseolus vulgaris, var. Linden) Journal of Agricultural and Food Chemistry 38(7): 1523-1529.

Wu W Williams W P Kunkel M E Acton J C Huang Y Wardlaw F B and Grimes L W 1996 Amino acid availability and availability-corrected amino acid score of red kidney beans (Phaseolus vulgaris L.). Journal of Agricultural and Food Chemistry 44(5): 1296-1301.

Zelaya R L Rios J J Paz P López S Valdivié M and Martínez Y 2022 Effect of the inclusion of L-carnitine on egg quality and productivity of Hy-Line Brown® laying hens. Cuban Journal of Agricultural Science 56(1): 1-10.