486
A. Soliman and A. M. Safwat
As soon as laying hens reach sexual maturity, ambient temperature becomes an
important factor affecting production. The average feed consumption is 1.6% and the
energy consumed is 2.3% for every 1° above the ideal temperature. At temperatures
above 30 °C, both food consumption and egg production are reduced by 5% and
1.5%, respectively. The decrease in food consumption (50%) was found when the
temperature rises from 21 to 38 °C and most of this decrease is due to the lack of
the needs of the preservative body. Treating this decrease by increase the rest of the
nutrients in the feed to overcome most of the harmful effects of the heat from an
improvement in egg production and the egg weight, but he could not overcome the
deterioration of the egg shell quality.
3.1.1 Egg Quality
Several studies have indicated that the bad effect of heat stress on the quality of
internal and external eggs. This effect is clearly visible on the egg shell and calcium
carbonate deposition. This is reflected in the appearance of the eggshell and its
characteristics, with insufficient mineral sources and bicarbonate ions. The decrease
in egg weight was estimated at 0.07–0.98 g/egg for each 1° rise. The thickness of
the eggshell is reduced by high temperature, and it becomes more complicated at the
later ages of the egg production cycle. This decrease is attributed to the low intake of
calcium because of the low food consumption. The quality of the egg includes visible
natural measurements as well as flavor and aroma. The effect of high temperature
extends to the liquid components of the eggs, which quickly damage the internal
contents of the egg yolk and reduces the quality and grade of the egg. Leaving the
eggs for long periods under high temperature conditions lead to its total corruption,
and these changes include the rapid erosion of the chemical layer, the number of open
gaps, evaporation of large amounts of moisture content of the whiteness and with the
persistence of high temperature, the yolk loses part of its moisture, the coagulation
of the liquid components with rise. Fresh eggs production from layers is always of
high quality, and there are many factors that affect the quality of eggs before produce
it.
Changes in environmental conditions, especially the increase in temperature for
the laying hens housing, resulting in lower quality of albumen and shell weak strength
and small thickness and egg size, may be due to low consumption of food in the hot
atmosphere. The importance of the role of management in the production of high
egg quality in the case of high temperature, which is the selection of the strain that
produces high egg quality, the balanced diet, diseases control, physiological disorders, and the organization of lighting, and food programs to control the beginning
of the egg production. The eggs are damaged and reduced quality if not handled
correctly. The most changes associated with changes in temperature is to increase
the air sac size as the resulting of losing moisture, where the amount of evaporation
for stored eggs depends on the environment temperature, humidity and ventilation as
well as shell porosity. The signs of low egg quality turn into the water situation, and
this shift depends on the heat stress, which is accompanied by natural reactions and
A. Soliman and A. M. Safwat
As soon as laying hens reach sexual maturity, ambient temperature becomes an
important factor affecting production. The average feed consumption is 1.6% and the
energy consumed is 2.3% for every 1° above the ideal temperature. At temperatures
above 30 °C, both food consumption and egg production are reduced by 5% and
1.5%, respectively. The decrease in food consumption (50%) was found when the
temperature rises from 21 to 38 °C and most of this decrease is due to the lack of
the needs of the preservative body. Treating this decrease by increase the rest of the
nutrients in the feed to overcome most of the harmful effects of the heat from an
improvement in egg production and the egg weight, but he could not overcome the
deterioration of the egg shell quality.
3.1.1 Egg Quality
Several studies have indicated that the bad effect of heat stress on the quality of
internal and external eggs. This effect is clearly visible on the egg shell and calcium
carbonate deposition. This is reflected in the appearance of the eggshell and its
characteristics, with insufficient mineral sources and bicarbonate ions. The decrease
in egg weight was estimated at 0.07–0.98 g/egg for each 1° rise. The thickness of
the eggshell is reduced by high temperature, and it becomes more complicated at the
later ages of the egg production cycle. This decrease is attributed to the low intake of
calcium because of the low food consumption. The quality of the egg includes visible
natural measurements as well as flavor and aroma. The effect of high temperature
extends to the liquid components of the eggs, which quickly damage the internal
contents of the egg yolk and reduces the quality and grade of the egg. Leaving the
eggs for long periods under high temperature conditions lead to its total corruption,
and these changes include the rapid erosion of the chemical layer, the number of open
gaps, evaporation of large amounts of moisture content of the whiteness and with the
persistence of high temperature, the yolk loses part of its moisture, the coagulation
of the liquid components with rise. Fresh eggs production from layers is always of
high quality, and there are many factors that affect the quality of eggs before produce
it.
Changes in environmental conditions, especially the increase in temperature for
the laying hens housing, resulting in lower quality of albumen and shell weak strength
and small thickness and egg size, may be due to low consumption of food in the hot
atmosphere. The importance of the role of management in the production of high
egg quality in the case of high temperature, which is the selection of the strain that
produces high egg quality, the balanced diet, diseases control, physiological disorders, and the organization of lighting, and food programs to control the beginning
of the egg production. The eggs are damaged and reduced quality if not handled
correctly. The most changes associated with changes in temperature is to increase
the air sac size as the resulting of losing moisture, where the amount of evaporation
for stored eggs depends on the environment temperature, humidity and ventilation as
well as shell porosity. The signs of low egg quality turn into the water situation, and
this shift depends on the heat stress, which is accompanied by natural reactions and