Nutrition Management Guide

by Poultry farmer – Miriam Rolling| Last Updated– 09 January 2021

Many years of genetic research by Hendrix Genetics have developed layers with excellent traits including livability,
production and egg quality.
These highly favorable genetic characteristics can only be fully realized when layers are provided with good
management, which includes, but is not limited to, good quality feed, suitable housing and proper management
The purpose of this nutrition management guide is to help producers to gain the best possible results from their
investment. This will be achieved by providing conditions in which the layers can thrive. The information supplied in
this publication is based on the analysis of extensive research and field results, produced over time and with many
years of experience.
We do recognize that many egg producers have developed their own management program, based on specific housing
types, climate, feed, market conditions and other factors. These individual management techniques will also be the
result of experience and many of these techniques will work for our layers as well.
Therefore, do not hesitate to use your own experience in conjunction with the guidelines in this guide. And of course,
do not hesitate to consult our distributors who will be happy to help in any way they can.

Villa ‘de Körver’
P.O. Box 114
5830 AC Boxmeer
The Netherlands, EU
T +31 485 319111
Version L7121-2
Nutrition Management Guide – Hendrix Genetics 3
Contents Nutrition Management Guide
Introduction 2
Rearing period
Feeding during the rearing period 4
Production period
Feeding program during the production period 8
Energy level selection during the production period 10
Amino acids requirements 12
Feed formulation 13
Calcium nutrition and particle size 16
Mineral and oil level recommendations 18
Feed presentation 20
Suggested premix composition 24
4 Nutrition Management Guide – Hendrix Genetics
Table 2. Effect of amino acid content on bodyweight of pullets
(in % of the recommendations) 100% 90%
Protein (%) 20 18
Digestible Lysine (%) 1.01 0.91
Digestible Methionine+Cystine (%) 0.76 0.69
Weight at 4 weeks (g) 335 302
Source: Bourgon, 1997
After 10 weeks of age, pullets correctly regulate their energy intake according to the energy level of the diet, in both
hot and temperate climates. Underconsumption during that period is often the result of a poor grit size. The objective
is to develop the pullet’s ability to eat feed, so that it can increase its consumption by approximately 40% in the first
few weeks of lay.
During the period 10-17 weeks, it is important to develop the digestive system by using diets with an energy
concentration less than or equal to that of the layer’s diet.
Protein requirements
The amino acid requirements are dependent on the feed conversion ratio and, therefore on age; that is why, when
young, the requirements expressed in mg of amino-acids per gram of growth are the same as for a broiler.
Table 2 shows the influence of amino acid content on the weight of pullets at 4 weeks.
Table 1. Energy level and feed presentation on body weight of pullets
Dietary Energy Level
Bodyweight at 5 weeks
Bodyweight at 5 weeks
3100 kcal 375 g 412 g
2790 kcal 345 g 405 g
Source: Newcombe, 1985
Rearing Period
Feeding during the rearing period
Energy level
During the first few weeks of life, young pullets, are incapable of regulating their energy intake according to the energy
concentration of the diet. It takes weeks to develop the digestive tract.
During the first 8-10 weeks, any increase in the energy level is accompanied by an increase in growth. When given the
feed in a crumb form, young pullets can increase their feed intake.
Table 1 shows the influence of energy level and presentation method on the bodyweight of pullets at 5 weeks of age.
Nutrition Management Guide – Hendrix Genetics 5
Nutrition Management Guide
In hot climates, the amino acid and mineral concentration should be slightly higher than in temperate climates. What
results in a reduction in the maintenance requirement, and, therefore in the feed conversion ratio.
Feed presentation
Feed consumption is determined to a large extent by the form of presentation and the stage to which the digestive
tract has developed. Presenting feed in crumb form makes it easier for the chicken to eat it, reduces the time taken in
eating, and encourages growth. The energy cost of eating, thus saved, gives an improvement in feed conversion ratio.
Any delay in growth during the first few weeks will be reflected in a reduced bodyweight at 17 weeks and in later
performance. It is, therefore, extremely important to use a starter diet for the first 4 or 5 weeks, which has an amino
acid/protein ratio similar to that of a broiler. Any amino acid deficiency will result in a reduction in growth rate and an
increase in the feed conversion ratio.
This benefit of feeding crumbs will only be obtained when the birds have access to good quality crumbs in the feeders.
A poor quality crumb can lead to a build-up of fine particles in the feeders and, therefore have the opposite effect to
that sought. From 0 to 4/5 weeks, we recommend using a crumbed diet, after which mash, with a good particle size,
should be used. It is, however, possible to use a granular feed later, where the grinding is coarser, or even as crumbs,
if needed. However, we recommend using a mash diet from 12 weeks, to avoid the risk of under-consumption at the
beginning of the sexual maturity, if the change is made later.
Table 3. Effect of amino acid deficiency on bodyweight, feed consumption, feed conversion of pullets
Amino acid content of diets
(in % of the recommendations) 100% 90%
Bodyweight at 28 days (g) 335 302
Bodyweight at 118 days (g) 1685 1630
Feed consumption (g) 6951 6904
Feed conversion ratio 4.12 4.24
Source: Bougon, 1997
Table 4. Feed presentation on bodyweight of pullets
Form of dietary presentation Mash Crumbs Difference
Weight at 70 days (g) 984 1016 + 32 g
Weight at 99 days (g) 1344 1405 + 61 g
Weight at 123 days (g) 1589 1664 + 75 g
Source: Internal research
The bird’s appetite for feed depends on its particle size. After 4 weeks, we recommend the following particle sizes:
• Particles below 0.5mm: 15% maximum
• Particles above 3.2mm: 10% maximum
At least 75 to 80% of the particles should be between 0.5 and 3.2mm. If this standard cannot be achieved, it is
preferable to use a diet of good quality crumbs.
Development of the digestive system
The achievement of good growth and a rapid increase in feed consumption at start of lay depends on the chicken
having a well-developed digestive system, especially a good strong gizzard.
Using feed of good particle size, giving grit during rearing and/or using limestone granules from 10 weeks will all
contribute towards good gizzard development.
Between 3 and 10 weeks, we recommend that 3 gram per pullet per week (particle size 2 to 3mm) are offered. After
10 weeks, this can be increased to 4 to 5 gram (particle size 3 to 5mm). It is also possible from 10 weeks onwards to
use a diet in which 50% of the calcium is supplied in carbonate form, with a particle size of 2 – 4mm.
Feed specifications during rearing period
These requirements are based on the “European Amino Acids Table” (WPSA, 1992) of raw materials composition
and expressed in table 5 as digestible amino acids by using the digestibility coefficients mentioned in the “Tables de
composition et de valeur nutritive des matières premières destinées aux animaux d’élevage” (INRA editions 2002).
Please see table on the next page.
6 Nutrition Management Guide – Hendrix Genetics
Nutrition Management Guide – Hendrix Genetics 7
8 Nutrition Management Guide – Hendrix Genetics
Table 5. Amino acid and nutrient requirements for all layers at all ages
Between 18 & 24°C
Diet Starter Grower Pullet Pre-lay
Units 0 – 4 weeks 4 – 10 weeks 10 – 16 weeks 112 days to
1 – 28 days 28 – 70 days 70 – 112 days 2% lay
Metabolisable energy Kcal/kg 2950-2975 2850-2875 2750 2750
MJ/kg 12.3-12.4 11.9-12.0 11.5 11.5
Crude protein % 20.5 19 16 16.8
Methionine % 0.52 0.45 0.33 0.40
Methionine + Cystine % 0.86 0.76 0.60 0.67
Lysine % 1.16 0.98 0.74 0.80
Threonine % 0.78 0.66 0.50 0.56
Tryptophan % 0.217 0.194 0.168 0.181
Digestible amino acids
Dig. Methionine % 0.48 0.41 0.30 0.38
Dig. Meth. + Cystine % 0.78 0.66 0.53 0.60
Dig. Lysine % 1.00 0.85 0.64 0.71
Dig. Threonine. % 0.67 0.57 0.43 0.48
Dig. Tryptophan % 0.186 0.166 0.145 0.155
Major minerals
Calcium % 1.05 – 1.10 0.90 – 1.10 0.90 – 1.00 1 2 – 2.10 1
Available Phosphorus % 0.48 0.42 0.36 0.42
Chloride minimum % 0.15 0.15 0.14 0.14
Sodium minimum % 0.16 0.16 0.15 0.15
Above 24°C
Diet Starter Grower Pullet Pre-lay
Units 0 – 5 weeks 5 – 10 weeks 10 – 16 weeks 112 days to
1 – 35 days 35 – 70 days 70 – 112 days 2% lay
Metabolisable energy Kcal/kg 2950-2975 2850-2875 2750 2750
MJ/kg 12.3-12.4 11.9-12.0 11.5 11.5
Crude protein % 20.5 20.0 16.8 17.5
Methionine % 0.52 0.47 0.35 0.42
Methionine + Cystine % 0.86 0.80 0.63 0.70
Lysine % 1.16 1.03 0.78 0.84
Threonine % 0.78 0.69 0.53 0.59
Tryptophan % 0.217 0.207 0.175 0.190
Digestible amino acids
Dig. Methionine % 0.48 0.43 0.32 0.40
Dig. Meth. + Cystine % 0.78 0.69 0.56 0.63
Dig. Lysine % 1.00 0.89 0.67 0.74
Dig. Threonine. % 0.67 0.61 0.45 0.50
Dig. Tryptophan % 0.195 0.175 0.152 0.163
Major minerals
Calcium % 1.05 – 1.10 0.95 – 1.10 0.95 – 1.05 1 2.1 – 2.2 1
Available Phosphorus % 0.48 0.44 0.38 0.44
Chloride minimum % 0.16 0.16 0.15 0.15
Sodium minimum % 0.17 0.17 0.16 0.16
1 It is possible to supply 50% of the calcium in granular form (2-4mm diameter)
Nutrition Management Guide – Hendrix Genetics 9
Feeding program during rearing period
Basic rules of our feeding program
Feeding the birds must be simple, to reduce the risk of errors at varying levels in the manufacturing and delivery
process. There are also additional reasons which are related to the birds directly. For example, birds are very sensitive
to the feed presentation and the introduction of new raw materials. For this reason, we recommend a limited number
of feed changes.
Amino acid requirements depend on the productivity of the flocks and the uniformity of productivity. Our amino
acid recommendations are based on an average productivity of 60g per day. At 50 weeks, the egg mass produced is
around 58g. A lot of birds can produce more than 60g of egg mass over a period of 50–65 weeks. This is the reason
why it is difficult to reduce the amino acids levels after 50 weeks without affecting the productivity.
A deficiency in amino acids reduces in a first-time egg weight and in a second time the persistency, around 4 or 5
weeks later.
Pre-lay feed or layer 1
Medullary bone is developed in long bone before the first ovulation. The total calcium contained in this medullary is
around 1.5 to 2 grams. A pre-layer feed with a higher calcium level is needed to establish this bone reserve. It must be
used from approximately 16 weeks. Its characteristics are similar to the layer 1, but with a level of calcium of 2–2.2%.
Don’t forget to use the layer 1 before 2% lay. If the change is realized later, the earliest birds ingest around 1.8g of
calcium and need to produce a shell with 2g of calcium. They will stop or reduce laying for some days and will produce
eggs without shell. These birds will exhibit cage layer fatigue later, and osteoporosis at the end of lay.
The risk can be reduced by using a layer 1 instead of a pre-lay feed. However, if the limestone is in 2-4mm particles
form, it is possible to use the layer 1 at 16 weeks. The main reason for the use of pre-lay feed was the risk of under
consumption when the limestone used was in powder form.
Layer 1
Layer 1 has to be satisfying the amino acids requirements for growth and production at a time where the feed
consumption is lower. At start of lay, feed consumption is lower because the birds have not yet reached their adult
bodyweight. Growth is not completely finished by 28 weeks. With regard to protein, a requirement for growth is
added to the requirement for production.
From a practical point of view, we have estimated that it is necessary to increase the concentration of amino acids by
about 6% during the 18-28 week period in relation to the feed consumption observed after 28 weeks.
Production Period
10 Nutrition Management Guide – Hendrix Genetics
This feed must be used until the moment that the feed consumption is normal or an average egg size of 60-61g is
obtained, or around 26-28 weeks.
At the onset of lay, it is desirable to encourage feed consumption and quickly to obtain eggs of marketable size.
For this, a feed enriched in fat allows to improve the presentation of diet which gives an increase in feed consumption.
Oils rich in polyunsaturated fatty acids are responsible for a large increase in egg weight.
Layer 2
This feed must be used from 26-28 weeks until 50 weeks, or end of lay. If it is possible, it is good to increase the
limestone level at 50 weeks to reduce the percentage of seconds. Birds have daily requirements for amino-acids and
minerals, consequently, the percentage of nutrients must be defined according to the feed consumption observed.
The feed consumption depends mainly on the energy requirement and on the temperature.
Layer 3
Amino acids requirement: Taking into account persistency in lay, individual variability and egg weight, the requirement
for amino acids does not fall throughout the laying period. In an economic context, it may be worth reducing the
safety margins slightly. However, the best results, in terms of productivity and feed conversion ratio, are obtained,
when the intake level of amino acids is maintained. Any deficiency of amino acids, no matter, which type of amino
acid, shows up as a reduction in performance, of which 2/3 is due to a reduction in rate of lay and the remaining 1/3
is a decrease in mean egg weight. It is, therefore, not possible to reduce egg weight towards the end of lay by reducing
the amino acid concentration without bringing about a reduction in rate of lay.
Persistency in lay has improved considerably (30 to 50 weeks above 90% lay). An analysis of the individual
performance over the period 40-66 weeks shows that 66% of the birds had performance above average. The 40% best
layers had laid 177 eggs in 182 days and/or 63.2 g of egg mass per day.
Table 6. Production levels of birds in a flock: average versus best performing
Quintile Rate of lay Egg Mass/day
1st 98.2% 65.0 g
2nd 96.3% 61.4 g
3rd 94.1% 59.1 g
4th 90.1% 56.0 g
5th 76.6% 47.8 g
Mean 91.0% 57.8 g
% of pullets above the mean 66.3% 60.4%
Source: Internal research
Nutrition Management Guide – Hendrix Genetics 11
Nutrition Management Guide
Egg weight:
A reduction of the oil percentage and energy level is a way to get a stabilization of the egg weight.
Shell quality:
Shell weight increases with age throughout lay. For that reason, we advise increasing the calcium concentration in the
diet from 50 weeks of age.
Energy level selection during the production period
Influence of the energy level on productivity
Results from experiments on the effect of the feed energy level on production, carried out during the last 15 years,
with white or brown strains, conclude that: Between 2400 and 3000 Kcal, for an energy level reduction of 100
Kcal, the energy consumption drops by an average of 1.2% when the effect of diluting the feed is studied, and by
1.4% when the reduction in fat levels is studied. The energy level of the feed has little effect on the number of eggs
produced, and, in all cases, the differences are less than 1%.
The egg weight reduces in accordance with the reduction in the feed energy level. The reduction can be estimated at
about 0.5% or 0.3g for a variation of 100 kcal. The consumption rate, expressed in Kcal per gram of egg produced,
always improves with the dilution of the feed. The gain is about 0.8% for 100 Kcal. This rate gain is a result of a
reduction in body weight, an improvement in feather cover and an improvement in the digestibility of the feed.
In many experiments, the addition of fats seems to have a specific effect on the energy consumption due to an
improvement in palatability and the physical form of the feed. When the feed is diluted, the reduction in consumption
is particularly marked at the time of the change. Laying hens take several weeks to increase their level of consumption.
Influence of the fiber level on productivity
Feed dilution forces hens to increase the volume and quantity of feed ingested and, therefore, to increase the feed
consumption time. There is no longer any doubt that feed dilution brings about an improvement in plumage and a
reduction in feather pecking itself. This explains the mortality reduction observed in certain trials using diluted diets.
Comparison between feed in meal or pellet form shows that the consumption times are lower when the feed is in
pellet or crumb form. This explains why feed in pellet form causes deterioration in plumage and increases feather
Even though most researchers are in agreement over establishing a relationship between consumption time and feather
pecking, some very recent studies show a specific requirement for insoluble fiber. Indeed, it appears that there is a
specific requirement for insoluble fiber.
Table 7. Effect of age on egg number and egg shell weight
Age of the control Number of eggs controlled Eggshell weight (g)
Shell weight at 30 weeks g 923 6.25
Shell weight at 42 weeks g 909 6.39
Shell weight at 50 weeks g 807 6.32
Shell weight at 60 weeks g 732 6.51
Source: Internal research
12 Nutrition Management Guide – Hendrix Genetics
The absence of insoluble fibers in the feed is responsible for the consumption of feathers and their presence in the
gizzard, even when hens are housed in individual cages. Some studies make it possible to conclude that insoluble fibers
do influence the quality of plumage and on mortality. The specific size of the fibers, mainly lignin, would seem to be
We have noted that countries using sunflower meal in quite significant quantities have lower mortalities than those
of countries that do not use it, whether using cages or floor systems. Very positive effects were observed after the
introduction of sunflower meal to feed for free-range hens.
Effect of granulometry
Feed consumption is highly dependent upon granulometry. Chickens have a marked preference for grains. They are
easy to pick up and do not lead to beaks becoming clogged. A hen will always tend to leave fine particles. Following
trial was carried out: a commercial feed, of good particle size, was re-milled through a finer screen. The feeds were
distributed from 19 weeks of age. The results of the trial are shown in tabel 8.
Feed consumption is reduced by about 4g when the feed is finely ground. This leads to a reduction of egg mass
produced. Distribution of fine feed is equivalent to rationing for hens. In this experiment, the laying rate proves to be
affected more than the egg weight. Sometimes in other experiments, the reverse is observed.
Energy regulation is not specific to a breed, white egg layers or brown egg layers, but depends on the dilution methods
used. The feed density (gram per liter) seems to be the limiting factor in ingestion regulation. The presence of insoluble
fiber appears to be essential. It increases gizzard size, improves starch digestibility and limits feather pecking by
reducing the need to ingest feathers.
Conversely, the addition of fats brings about an improvement in feed palatability and thus an increase in energy
ingestion in proportions which can be very significant. Increase in egg weight is only one result of this. These effects
are dependent upon the quantity and type of fats added.
Table 8. Influence of feed granularity on performance of laying hens between 23 and 51 weeks
Particle size Standard Fine Difference in %
< 0.5 mm 9% 31%

3.2 mm 10% 0%
0.5 to 3.2 mm 81% 69%
1.6 mm 65% 21%
Laying, % 93.9 90.7 – 3.4
Egg weight, g 63.3 62.7 – 0.9
Egg mass, g/j 59.41 56.85 – 4.3
Consumption, g/j 118.1 114.2 – 3.4
Consumption Index 1.989 2.008 + 0.9
Weight at 33 wks. g 1.930 1.883
Source: Internal research
Nutrition Management Guide – Hendrix Genetics 13
Nutrition Management Guide
From a practical point of view, the effect of low density, high cellulose (insoluble fiber) raw materials may be balanced
by the use of fats. The feed presentation also has an effect on energy consumption. Too fine feed presentation causes
a reduction in energy consumption.
It thus appears that the three following factors must be controlled:
1) physical form of the feed
2) cellulose content
3) oil content
A balance between these three criteria must be sought in order to make possible the expression of genetic potential at
a lower cost.
Principal applications and recommendations
At the onset of lay, it is desirable to encourage feed consumption and quickly to obtain eggs of marketable size. For
this, a feed enriched in fat (1.5 to 2.5%) and incorporating a minimum of insoluble fiber is recommended. After the
onset of laying, a slightly lower energy level, richer in cellulose, will allow a good energy efficiency to be obtained
(expressed in kcal) and plumage to be maintained. This strategy could be particularly beneficial for alternative
production (free range, organic…), especially in the absence of ground litter.
From the practical point of view, the effect of raw materials which are rich in cellulose (insoluble fiber) and of low
density can be compensated for by the use of fat. Feed granulometry also affects energy consumption. Particles which
are too fine lead to a reduction in consumption.
Amino acids requirements
Genetic progress and nutritional consequences
Genetic progress has a considerable influence on dietary amino acid concentrations. Over the last 30 years, production
to a constant age has increased by more than 40%, while feed consumption has been reduced by about 10%. An
important consequence of this genetic progress has been a change in the daily amino acid requirements. It has also
called into question the practice of phase feeding, since productivity remains high over longer and longer periods. The
best units nowadays have daily egg outputs of over 60g/bird right up to, or over 52 weeks of age.
The implication of genetic change in deciding amino acid levels is, therefore, considerable. It can be approached in the
following way:
Classically, daily nutrient requirements have been expressed in mg/day. While this type of expression may be very easy
for the formulator to use, it does not allow for genetic progress, nor for genotypic differences. Those genotypes, which
produce large eggs, have larger daily requirements than those which produce small eggs.
Most researchers agree to the expression of nutrient requirements in mg of amino acids per gram of eggs produced.
This method enables us to tackle the ‘requirement’ starting from numerous experimental data sources. It is
more precise. The synthesis that we have carried out according to this method shows it to be an excellent way of
determining requirements.
Table 9. Feed conversion ratio over the period 30-50 weeks
1971 2.87 g of feed / g of egg
1981 2.36 g of feed / g of egg
2005 1.95 (-17%) g of feed / g of egg
Source: Internal research
14 Nutrition Management Guide – Hendrix Genetics
Ideal protein and amino acids requirements
The concept of ideal proteins is a means of expressing the requirements for amino acids as a percentage of the
requirement for LYS. There is a limited interest in applying this concept to layers. It implies that a balance between the
different amino acids is necessary for optimizing requirements. That would suggest that high protein or amino acid
levels would have a negative effect on performance.
In fact the formulator should make a point of satisfying the requirement for the following amino acids: MET – CYS – LYS

  • THR – TRP – ISO and VAL. This is only valid for diets and raw materials in common usage.
    Those requirements, which need to be defined by comparison with reference tables, have been expressed from NRC
    (1994) table of raw materials composition. These results have been expressed as digestible amino acids by using the
    digestibility coefficients mentioned in the RPAN 1993 tables. Giving the expression in the digestible form has reduced
    the variability of the results observed.
    Recommendations for amino acids expressed in total or digestible and ideal proteins established for a production of
    59.5 egg mass per day. Mass per day are shown in table 10.
    Feed formulation
    Bird requirements and formulation of diets should be made in terms of digestible amino acids. By formulating in
    digestible amino acids, one is better able to satisfy the requirements of the birds, to reduce the necessary safety
    margins and assess the raw materials according to their true biological value.
    Formulation according to total amino acids leads to the same nutritional value being given to all raw materials
    irrespective of their digestibility. That leads naturally to increasing the safety margins in order to guarantee fully
    meeting the requirements of the birds.
    When diets are formulated by taking into account the need to satisfy the requirement for each of the 7 essential
    amino acids, it doesn’t seem to be necessary to introduce a minimal constraint for protein. The requirements for the
    limiting amino acids are generally enough. On the other hand, if all the essential amino acids are not considered when
    formulating, it is necessary to use a constraint for minimum protein, to reduce the risk of a deficiency.
    Table 10. Recommendations for amino acids expressed in total or digestible and ideal proteins
    established for a production of 59.5 egg mass per day
    amino acids
    Ideal protein based
    on NRC 1994
    Requirements in mg per g
    based on NRC table 1994
    Daily Requirements based
    on NRC table 1994
    Dig. AA Total AA Dig. AA Total AA
    LYS 100 13.50 15.25 810 900
    MET 54 7.2 7.6 430 455
    MET + CYS 85 11.45 13.0 690 770
    TRY 22 3.00 3.5 180 280
    ILE 83 11.5 13.0 690 775
    VAL 93 12.6 14.2 760 840
    THR 70 9.4 11.0 565 655
    Nutrition Management Guide
    Nutrition Management Guide – Hendrix Genetics 15
    The experience acquired during the last decades in the feeding of layers, especially the use of synthetic lysine, has
    enabled us to assert that ISOLEUCINE and VALINE are becoming the limiting factors in layers feeds when meat
    products are excluded from the feed or when they are used in formulae based on wheat.
    TRYPTOPHAN is the limiting factor in formulae, where the base consists of maize, soybean meal and meat products.
    THREONINE and still less ARGININE do not appear to be limiting in the diets used nowadays. These last two amino
    acids need to be studied still further.
    When the requirements for ISO, VAL and TRY are covered, the requirements for the other essential and non-essential
    amino acids are always satisfied when 300mg of protein per gram of egg is supplied. When the feed formula takes
    into account the requirements for ISOLEUCINE and VALINE, it is not necessary to impose a constraint for a minimum
    protein level.
    The amino acid concentration of the diets, therefore, depends on:
    1) Potential of egg mass produced, which determines the daily requirements.
    2) The daily feed consumption which determines the amino acid concentration.
    Amino acids recommendations
    Formulation of layer diets can be carried out by introducing ISOLEUCINE and VALINE as nutritional constraints,
    replacing protein as a constraint. If this is not possible, some indications for a minimum of protein for feed not
    containing meat and bone meal (MBM), are given hereafter.
    From a practical point of view, we advise to increase the concentration of amino acids by about 6% during the
    18-28 weeks’ period in relation to the feed consumption observed after 28 weeks. Total or digestible amino acids
    levels are established for a production of 59.5g egg mass per day.
    16 Nutrition Management Guide – Hendrix Genetics
    Nutrition Management Guide – Hendrix Genetics 17
    Nutrition Management Guide
    Table 11. Recommendations for amino acids expressed as total and digestible amino acids for a production
    of 59.5 egg mass per day and given for alternative feed intake levels.
    Average feed intake observed
    after 28 wks in g/day 105 110 115 120 125
    From 2% lay to 28 weeks old (1)
    Protein w/o MBM % (18.2-18.7) (17.7-18.2) (17.2-17.6) (16.7-17.2) (16.2-16.7)
    Protein with MBM % (19.5-20.0) (18.9-19.4) (18.2-18.8) (17.9-18.4) (17.4-17.9)
    Total amino acids % :
    Lysine 0.91 0.87 0.83 0.80 0.77
    Methionine 0.46 0.44 0.42 0.41 0.39
    Methionine + Cystine 0.77 0.74 0.71 0.68 0.65
    Tryptophan 0.210 0.200 0.192 0.184 0.176
    Threonine 0.66 0.63 0.60 0.58 0.56
    Isoleucine 0.80 0.77 0.73 0.70 0.67
    Valine 0.86 0.82 0.79 0.76 0.73
    Digestible amino acids % :
    Lysine 0.81 0.78 0.74 0.71 0.68
    Methionine 0.44 0.42 0.40 0.38 0.37
    Methionine + Cystine 0.70 0.66 0.64 0.61 0.59
    Tryptophan 0.182 0.173 0.166 0.159 0.153
    Threonine 0.57 0.54 0.52 0.49 0.47
    Isoleucine 0.73 0.70 0.67 0.64 0.61
    Valine 0.78 0.75 0.71 0.68 0.66
    From 28 weeks to the end of lay
    Protein w/o MBM % (17.4-17.9) (16.9-17.4) (16.4-16.9) (15.9-16.4) 15.4-15.9)
    Protein with MBM % (18.7-19.2) (18.1-18.6) (17.6-18.1) (17.1-17.6) (16.6-17.1)
    Total amino acids % :
    Lysine 0.86 0.82 0.79 075 0.72
    Methionine 0.44 0.42 0.40 0.38 0.37
    Methionine + Cystine 0.73 0.70 0.63 0.64 0.61
    Tryptophan 0.198 0.189 0.181 0.173 0.166
    Threonine 0.62 0.60 0.57 0.55 0.52
    Isoleucine 0.76 0.72 0.69 0.66 0.64
    Valine 0.81 0.78 0.74 0.71 0.68
    Digestible amino acids % :
    Lysine 0.77 0.73 0.70 0.67 0.64
    Methionine 0.41 0.40 0.38 0.36 0.35
    Methionine + Cystine 0.66 0.63 0.60 0.58 0.55
    Tryptophan 0.170 0.162 0.155 0.148 0.142
    Threonine 0.53 0.51 0.49 0.47 0.45
    Isoleucine 0.69 0.66 0.63 0.60 0.58
    Valine 0.74 0.70 0.67 0.65 0.52
    These requirements are based on the “European Amino Acids Table” (WPSA, 1992) of raw materials composition and
    expressed as digestible amino acids by using the digestibility coefficients mentioned in the “Tables de composition et
    de valeur nutritive des matières premières destinées aux animaux d’élevage” (INRA editions 2002).
    18 Nutrition Management Guide – Hendrix Genetics
    Calcium nutrition supply and particle size
    Year after year, improvements in productivity are brought about by reducing the time taken to produce an egg.
    Nowadays, the time taken to produce the egg is close to 24 hours which enables us to achieve very high rates of
    production with eggs being laid early in the morning.
    Calcification of the eggshell takes about 12 hours being completed, on average 2h-2h30min. before oviposition.
    Eggshell quality depends to a large extent on the quantity of calcium available in the digestive tract during the night
    and the form in which calcium carbonate is supplied play determining roles in deciding shell quality.
    Some differences exist between white and brown layers for a program of 16 hours of light:
    Calcification of the shell is mainly realised during the night. A high percentage of brown birds stop calcification at lights
    on or just after while white layers finish their shell after lights on.
    Calcium absorption
    During shell formation, the bird uses the calcium contained in the digestive tract, it is dissolved by abundant secretion
    of Hydrochloric Acid. Regular gizzard contractions deliver calcium through the intestine. When the quantity of calcium
    is insufficient, the bone reserves are used (the calcium is deposited and the phosphorus eliminated by the kidneys). It
    has been demonstrated many times that birds which are forced to use their bone reserves produce eggs of poorer shell
    quality. Sauveur (1988) said “The eggshells are thicker when the part played by the bones is small”. Calcium deposition
    is slow during the first 5 hours after it enters the shell gland. After that and for approximately 10 hours, the rate of
    shell deposition is rapid and linear. Calcium absorption varies from approximately 30% to over 70% between periods
    without calcification and period of shell formation. For this reason, every increase in the quantity of calcium available
    at the end of the night leads to an improvement in shell quality.
    Table 12. Moment of calcium deposit for white and brown layers
    In Average (hours after lights on) White Layers Brown Layers
    Beginning of large calcium deposit 15h30 (+/- 2hrs) 12h30 (+/- 2hrs)
    End of calcium deposit 3h30 (+/- 2hrs) 0h30 (+/- 2hrs)
    Nutrition Management Guide – Hendrix Genetics 19
    Nutrition Management Guide
    Importance of large limestone particle size
    Large size of calcium and retention: Large sizes of limestone (over 2mm) are retained in the digestive tract and
    dissolved slowly during the shell formation providing a more regular release of calcium.
    The influence of particle size on the ‘in vitro’ and ‘in vivo’ solubility of calcium and its retention in the gizzard 5 hours
    after food withdrawal.
    Large size of calcium and shell quality
    The availability of calcium at the end of the night period is improved by using a coarse calcium source with a low
    solubility. In using a low solubility coarse limestone, the quantity of calcium available during the beginning of shell
    formation is reduced and improved at the end of the night.
    The most important parameter is the solubility. The lower the solubility, the better the shell quality will be. Chen and
    Coon (1990) found a very high coefficient of regression between Shell Index and solubility. Coarse limestone with a
    high solubility is not able to optimize the shell quality. Coarse limestone with a high solubility is not able to optimize
    the shell quality. If limestone size and solubility are correct, there is no advantage in using oyster shell.
    Table 13. Solubility of limestone by particle size
    Diameter of limestone
    particles average size
    Solubility (%)
    In vitro In vivo Retention in the gizzard (g)
    A B A B A B
    3.3 – 4.7 29.8 36.3 84.8 82.5 15.4 3.4
    2.0 – 2.8 45.8 54.8 79.0 84.0 11.8 4.3
    1.0 – 2.0 49.3 57.7 77.8 74.4 5.5 4.7
    0.5 – 0.8 63.1 67.6 76.5 69.4 0.7 1.6
    Source: Zhang et al., 1997
    A = low solubility sample B = high solubility sample
    Size of
    Deposited in
    the faeces
    Stored in the gizzard
    after 24 hours
    Calcium retained
    g %
    0.5 to 0.8 mm 44% 0 1.94 52
    2 to 5mm 16% 10% 2.40 64
    Source: Rao and Roland, 1989
    Table 14. Relationship between particle size and calcium retention for a consumption of 3.75 g calcium
    Table 15. Relation between limestone particle size and egg shell quality traits
    Av. screen size
    Shell index
    Shell weight
    Shell thickness
    3.36 75.6 5.27 1.0837 302
    2.38 74.3 5.21 1.0839 290
    1.68 74.0 5.23 1.0828 296
    1.02 73.7 5.16 1.0825 294
    0.50 73.0 5.05 1.0821 286
    0.15 70.9 4.97 1.0802 280
    Source: Chen and Coon, 1990
    Importance of soluble form of calcium
    At “lights-on”, those birds which have not completed calcification should have access to powdered calcium, which is
    very rapidly dissolved and absorbed. It takes no more than 30 minutes between the intake of calcium and the moment
    where calcium is incorporated into the shell. Koreleski et al (2003) studied which percentage of coarse particles of
    limestone are to be used with brown birds. The best result is observed with 60% of large particles.
    White layers finish their shells after “lights on”, consequently 50% of the calcium has to be in particles of 2 to 4mm
    and 50% in a powder form.
    Around 40% of brown layers have finished their eggshell at “lights on”, consequently 65% of the calcium has to be in
    particles of 2 to 4mm and 35% in a powder form.
    Mineral and oil level recommendations
    Table 17. Daily requirement of nutrients during various stages in production
    Daily Requirement From 17 to 28 weeks From 28 to 50 weeks After 50 weeks
    Available phosphorus (1) mg 400 380 340
    Available phosphorus (2) mg 440 420 380
    Total calcium g 3.9 – 4.1 4.1 – 4.3 4.3 – 4.6
    White birds:
    Coarse calcium (2 to 4mm) g 2.0 2.1 2.2
    Brown birds:
    Coarse calcium (2 to 4mm) g 2.6 2.7 2.9
    Sodium minimum mg 180 180 180
    Chloride mini-maxi mg 170 – 260 170 – 260 170 – 260
    Oil mini-maxi (3) % 2 – 3 1 – 2 0.5 – 1.5
    Fiber A minimum of coarse fibre or lignin is required to prevent
    feather pecking and improve the feed digestibility
    20 Nutrition Management Guide – Hendrix Genetics
    Table 16. Effect of the percentage of limestone in particles of 2 to 4mm on the shell characteristics
    Percentage of large
    particles used
    Eggshell breaking
    strength N
    Shell weight
    Shell Index
    mg per cm²
    Shell thickness
    0 33.6a 5.70 78.3 365
    20 35.4ab 5.80 78.9 365
    40 38.0d 5.75 79.7 368
    60 38.2d 5.88 80.8 374
    80 36.9cd 5.70 79.1 364
    100 36.1bc 5.89 81.4 370
    Source: Koreleski et al, 2003
    Nutrition Management Guide
    Table 18. Nutrient requirement in percentage depends on feed intake after 28 weeks of age
    Average feed intake observed
    after 28 weeks in g / day 105 110 115 120 125
    From 2% lay to 28 weeks old
    Available phosphorus (1) % 0.41 0.39 0.37 0.35 0.34
    Available phosphorus (2) % 0.45 0.43 0.41 0.39 0.37
    Total calcium % 3.9 – 4.1 3.8 – 4.0 3.6 – 3.8 3.4 – 3.6 3.3 – 3.5
    Sodium minimum % 0.18 0.17 0.16 0.16 0.15
    Chloride mini-maxi % 0.17 – 0.26 0.16 – 0.25 0.16 – 0.24 0.15 – 0.23 0.15 – 0.22
    From 28 weeks to 50 weeks
    Available phosphorus (1) % 0.36 0.34 0.33 0.32 0.31
    Available phosphorus (2) % 0.40 0.38 0.37 0.35 0.34
    Total calcium % 3.9 – 4.1 3.7 – 3.9 3.6 – 3.8 3.4 – 3.6 3.3 – 3.5
    Sodium minimum % 0.17 0.16 0.16 0.15 0.14
    Chloride mini-maxi % 0.16 – 0.25 0.16 – 0.24 0.15 – 0.23 0.14 – 0.22 0.14 – 0.21
    From 50 weeks to the end of lay
    Available phosphorus (1) % 0.32 0.30 0.29 0.28 0.27
    Available phosphorus (2) % 0.36 0.34 0.33 0.32 0.30
    Total calcium % 4.1 – 4.3 3.9 – 4.1 3.8 – 4.0 3.6 – 3.8 3.5 – 3.7
    Sodium minimum % 0.17 0.16 0.16 0.15 0.14
    Chloride mini-maxi % 0.16 – 0.25 0.16 – 0.24 0.15 – 0.23 0.14 – 0.22 0.14 – 0.21
    1) When coarse limestone is supplied as particles of 2 to 4mm, it is possible to use these values.
    2) We advise using these values when the calcium is supplied in powder form.
    3) Adding vegetable oils which are rich in unsaturated fatty acids increases egg weight. The suggested
    inclusion rate for medium to large sized eggs is 2-3%. For markets requesting small to medium sizes eggs, a lower
    inclusion rate, is advised. Therefore, diet should be adjusted according to each market’s preference for egg size.
    To avoid egg size becoming too large at the end of lay, we advise reducing the quantity of vegetable oil being used.
    Nutrition Management Guide – Hendrix Genetics 21
    Feed presentation
    Importance of the feed particle size
    Mixing difficulties, inappropriate particle size and separation problems have been resolved by milling the raw materials
    relatively fine.
    However, diets, which are too finely ground, often seriously reduce feed intake. Low consumption has been avoided
    by using diets presented as crumbs or pellets. In effect, the ease of eating and the reduction in feeding time, due to
    pelleting, leads to an increase in the number of feeds taken by the birds and in their growth. This effect is observed in
    both laying hens and broiler chickens.
    Birds are grain eaters and their feed consumption depends on feed presentation.
    Pelleted or crumbled diets for layers
    In theory, presenting a diet in crumb or pellet form will give higher feed consumption. That presupposes that the
    feeding systems in operation and the raw materials used are providing the laying hen with a good quality pellet or
    Very often, the difficulties in obtaining a good quality crumb are responsible for under-consumption and some
    technical problems because of:
    • the breaking down of the crumb in the feed distribution system
    • the build-up of fine feed particles in the feeders
    • more shell quality problems related to the difficulties in using a granular limestone
    • more feather pecking due to a shorter feeding time
    This all can result in increased manufacturing costs. To develop a good digestive system, it is necessary to have coarsely
    milled feed. With the intention of keeping good shell quality we suggest:
    • use granular limestone if the diameter of the diet is adapted
    • add some of the limestone after pelleting
    • distribute 3 to 4g per bird of granular limestone (2 to 4mm) in the poultry house each afternoon.
    Mash diets of good texture
    During rearing, except for the first 4 or 5 weeks, when the diet should be crumbs, a good particle size will allow good
    growth and the development of a robust digestive system.
    During the laying period, a good textured diet will allow the birds to increase their feed consumption, their production
    and their growth.
    Table 19 shows the results of Summers and Leeson (1979) when they were comparing a fine mash with a diet of 60%
    cracked maize and whole barley grains.
    22 Nutrition Management Guide – Hendrix Genetics
    Nutrition Management Guide – Hendrix Genetics 23
    Nutrition Management Guide
    In hot climates, a good textured feed can reduce the under-consumption experienced in summer.
    That’s why, we advise having at least 75 to 80% of the particles between 0.5 and 3.2mm. This type of diet is in fact
    easier and cheaper to produce, because the rate of output from the grinder is increased.
    Particle sizes less than 0.5mm: 15% maximum
    Particle sizes above 3.2mm: 10% maximum
    These recommendations also apply to the rearing diets after the age of 4 or 5 weeks. The attractiveness of the diet
    improves markedly if the fine particles are sticking together. That can be achieved by the addition of 1.5 to 2.5%
    vegetable oil.
    The choice of raw materials
    Avoid raw materials, which are too dusty, and do not grind ingredients, which don’t need grinding.
    When the diet does not contain meat meal 60 to 70% of the calcium carbonate should be supplied as granules of
    2-4mm diameter. When meat meal is included the proportion in granular form should be increased to 80%.
    The phosphates should be supplied as micro-granules.
    Grinding technique
    A well textured mash can be obtained by observing the following rules:
    • The speed at the periphery of the hammers should be 50 to 55 m/sec. This speed corresponds to about 1500 rpm
    for a grinder of 65cm diameter.
    • We recommend using grill mesh screens in preference to those with round perforations. They have a higher
    proportion of spaces and allow higher throughputs.
    • The hole diameters should be the following:
    • For wire screens = 8mm minimum
    • For screens with round perforations = 8mm minimum, 10mm maximum.
    • Note: Using worn hammers gives an increase in the percentage of fine particles and reduces the output of the
    • Only mill those raw materials that require it.
    • Check the texture of the raw material at least twice a week.
    Cracked Maize + Whole Barley Fine Mash
    Consumption (g/day) 114.5 102.0
    Rate of lay (%) 86.9 85.1
    Egg weight (g) 59.6 56.8
    Source: Summers and Leeson, 1979
    Table 19. Effects of structure on consumption and performance
    Fiber for layers
    Birds also have a specific requirement for fiber during egg production. They must find fiber in the feed or in their
    immediate environment. It has been shown that birds that are deficient in fiber ingest feathers as a fiber source.
    Feathers may be taken from the floor or pecked from other birds. Monitor feather presence on the floor and if no
    feathers are found, check gizzards for feathers. This is a valuable tool to identify the origin of feather pecking behavior
    in a flock.
    An appropriate supply of fibers results in a good feather cover, livability, intestinal health, digestion (of mainly starch)
    and drier manure quality. Livability is positively influenced by fibers because it increases the feeling of satiety in birds,
    which in turn results in quieter birds, by eliminating need for feather ingestion (pecking and cannibalism). Diluting the
    feed helps to maintain a good energy balance in older birds and to prevent fatty livers.
    Characteristics of good fiber sources for layers are insoluble fiber of a coarse structure. Cellulose, hemicellulose and
    especially lignin are classified as insoluble fiber. These fibers are not digested or fermented in the gastrointestinal tract,
    and therefore serve as filling material that stimulate gastrointestinal movements without increasing the viscosity of the
    intestinal contact. If fiber particles are small (finely ground), the effect on gastrointestinal movements is minimal and
    coarse fiber is recommended. Inclusion rates of 2.5% of insoluble fiber are considered to be low in fiber, while 5% of
    insoluble fiber is considered to be high in fiber. Beyond the start of lay fiber content can be increased. The inclusion of
    6-7% of insoluble fiber (by oat hulls) gives good results in terms of production parameters and livability.
    Fiber can be included in the feed or provided in the direct environment. Preferred “in-feed” insoluble fiber sources
    are oilseed meals like sunflower meal and rapeseed meal, but also oats and oat hulls. Cereal by-products (like bran)
    are also a good source of insoluble fiber, however cereal byproducts have a fine structure and therefore have minimal
    effect on gastrointestinal movements, which makes them less suitable as a fiber source.
    Fiber that is provided in addition to the diet can be coarse fiber such as straw, alfalfa (lucerne), wood shaving, rice/
    oat husk, silage, etc. These materials must be available in the building through round feeders, or directly as a ball on
    the scratching area. Birds must have free access to fiber sources at all times. We advise not spreading fiber directly on
    the floor. To prevent floor eggs, fiber supply must be introduced after the peak of production when the birds are well
    trained to use the nest.
    24 Nutrition Management Guide – Hendrix Genetics
    Nutrition Management Guide
    Nutrition Management Guide – Hendrix Genetics 25
    26 Nutrition Management Guide – Hendrix Genetics
    Suggested premix composition
    Table 20. Suggested premix composition for commercial layers
    For commercial layers
    Rearing period Laying period
    0-10 (weeks of age) 10 wks – 2% Lay
    Added trace elements mg per kg of diet
    Manganese (Mn) ppm 60 60 70
    Zinc (Zn) ppm 60 60 60
    Iron (Fe) ppm 60 60 60
    Iodine (I) ppm 1 1 1
    Copper (Cu) ppm 8 6 8
    Selenium (Se) ppm 0.25 0.25 0.25
    Cobalt (Co) ppm 0.25 0.15 0.15
    Added vitamins per kg of diet in IU or mg
    Vitamin A IU 13000 10000 10000
    Vitamin D3 IU 3000 2000 2500
    Vitamin E mg 25 25 20
    Vitamin K3 mg 3 3 3
    Vitamin B1 (Thiamine) mg 2 2 2
    Vitamin B2 (Riboflavin) mg 5 5 5
    Vitamin B6 (Pyridoxine) mg 5 5 5
    Vitamin B12 mg 0.02 0.01 0.015
    Nicotinic Acid (Niacin) mg 60 40 40
    Pantothenic acid mg 15 12 12
    Folic Acid mg 0.75 0.75 0.75
    Biotin mg 0.2 0.1 0.05
    Vitamin C in hot climate
    or during summer time mg 100
    Total Choline requirement per kg of diet (raw materials included) mg
    Choline mg/kg 1600 1400 1400
    Choline mg/day – – 160
    Add antioxidant
    Nutrition Management Guide – Hendrix Genetics 27
    Nutrition Management Guide
    Trace elements and vitamins should be correctly mixed before being added to the raw materials. Premixes have to be
    mixed at a minimum level of 3kg per tonne. Improper mixing or handling can be checked by dosing Manganese as a
    Toxicity of some minerals
    Maximum admissible levels for different minerals can be estimated as follows:
    Potassium 2000 ppm
    Sodium 5000 ppm
    Iron 500 ppm
    Zinc 2000 ppm
    Selenium 10 ppm
    Vanadium 10 ppm (due to contamination from rock phosphates)
    Magnesium 5000 ppm
    Chloride 5000 ppm
    Manganese 1000 ppm
    Copper 300-500 ppm
    Iodine 300-500 ppm
    Reference list
    Bougon, M., Joly, P., Influence du niveau énergétique sur les performances des pondeuses à oeufsroux et évolution
    de l’ingéré en fonction de l`âge. 2ême Journée de la Recherche Avicole (1997) 2:115–120.
    Koreleski, J., Swiatkiewicz, S., Calcium from limestone meal and grit in laying hen diets-effect on performance,
    eggshell and bone quality. J. Anim. Feed Sci. (2004) 13:635–645.
    Newcombe, M., Summers, J.D., Effect of increasing cellulose in diets fed as crumbles or mash on the food intake
    and weight gains of broiler and Leghorn chicks. British Poultry Science (1985) Vol. 26 , Iss. 1.
    Rao, K. S., Roland, D.A., Influence of dietary calcium level and particle size of calcium source on in vivo calcium
    solubilization by commercial Leghorns. Poultry science 68.11 (1989): 1499-1505.
    Sauveur, B,. Lésions osseuses et articulaires des pattes des volailles: rôles de l’alimentation.” INRA Prod. Anim 1.1
    (1988): 35-45.
    Zhang, B., Coon C.N., The relationship of calcium intake, source, size, solubility in vitro and in vivo, and gizzard
    limestone retention in laying hens. Poultry Science 76.12 (1997): 1702-1706.

The best Rat Proof Chicken Feeder

Rat Proof Feeder for chickens by Jennifer Behm - Chicken farmer| Last Updated– 04 January 2021 What type of chicken feeder is best? Chicken Treadle Feeder Rural365 17.6lb ...
Read More

Best organic chicken feed for laying hens

What's the Best CHICKEN FEED? by Jennifer Behm - Chicken farmer| Last Updated - 20 December 2020 What to feed your laying chickens?Organic Chicken Feed ...
Read More

What to feed your chickens so they don’t eat feathers

Chickens PECKING & EATING Feathers!? WHY & HOW to HELP! by Poultry farmer - Miriam Rolling| Last Updated– 09 January 2021 Hey, I'm going to ...
Read More

3 Questions Every New Chicken Owner Has

TOP 3 Questions about starting a chicken farm by Poultry farmer - Miriam Rolling| Last Updated– 09 January 2021 Building a Chicken Coop? Among one ...
Read More

5 Chicken Problems And How To Fix Them

TOP 5 laying chicken problems by Poultry farmer - Miriam Rolling| Last Updated– 09 January 2021 Why Did My Chickens Stop Laying Eggs Hens stop ...
Read More

3 Supplements Every Chicken Needs

TOP 3 Poultry Supplements by Poultry farmer - Miriam Rolling| Last Updated– 09 January 2021 The Types of Poultry Grit As unusual as chickens teeth" ...
Read More

Leave a Reply

Your email address will not be published. Required fields are marked *