16
E.-S. E. Omran and A. M. Negm
by heat stress conditions, which affect the production rate. Other effects that are
connected to heat stress include immunity reduction and weak immune response to
vaccines that decrease the resistance of birds to many infectious diseases. In laying
hens, the production is significantly decreased and does not reach to the peak a
decrease in the egg quality (e.g., thin and breakable eggshell) in addition to lower
egg weight with small size.
The last chapter in this section is titled “Climatic Change and Chicken Immunity ”.
The chapter is presented to compile the current knowledge about the importance and
impact of climatic change, warming the global, on chicken production, focusing on
chicken immunity. Chickens have very strong built-in defenses (immunity) against
diseases that are caused by overrunning of the body by various microorganisms
and toxins. Under stress conditions, avian blood tolerates a change from acid-base
balance to alkaline balance. There is a decline in the plasma, a reduced level of
vitamin C in the adrenal cortex, a reduction in lymphocytes, and a depression of
the immune response. As the temperature rises, the birds undergo many changes—
increased water consumption, respiration rate, body temperature, inferior egg quality,
and susceptibility to diseases.
The highly specific adaptive immune mechanisms are affected by heat stress.
In more specific, heat stress deteriorates the cell-mediated immune responses. As a
result of heat conditioning, biochemical and physiological mechanisms were induced
to cope with heat stress; this induction may have delayed production of additional
acute phase proteins to protect the cells from damage. The stress hormones—cytokine
interactions are responsible for altered immune functions during heat stress. Modernday molecular biology tools can help in understanding various cellular and molecular
mechanisms involved in the production, physiological and immunological aspects of
the poultry birds, which in turn can help in the development of breeds more adapted
to the climate changes.
3.5 Socioeconomic Impacts
The socioeconomic impacts of climate change are covered in three chapters. The
chapter titled “Climate Change, Agriculture, and Rural Communities’ Vulnerability
in the Nile Delta” discusses the severe impacts of climate change on agricultural
production and rural communities in the Nile Delta in Egypt. However, immediate
challenges, such as population growth, land fragmentation, and urban expansion on
agricultural land if not timely curbed will further exacerbate future climate change
impact. Agriculture in Egypt in general and in the Nile Delta in particular, is currently
facing other intense challenges resulting from the rapid population growth that is
exceeding 2.5% annually [13], thus augmenting agricultural land and irrigation water
scarcities.
Farmers in Egypt are expected to suffer from climate change impacts, and the
Nile Delta in the northern part of Egypt—comprising about 50% of the agricultural
land—is identified as one of the world’s three “extreme” vulnerability hotspots.
E.-S. E. Omran and A. M. Negm
by heat stress conditions, which affect the production rate. Other effects that are
connected to heat stress include immunity reduction and weak immune response to
vaccines that decrease the resistance of birds to many infectious diseases. In laying
hens, the production is significantly decreased and does not reach to the peak a
decrease in the egg quality (e.g., thin and breakable eggshell) in addition to lower
egg weight with small size.
The last chapter in this section is titled “Climatic Change and Chicken Immunity ”.
The chapter is presented to compile the current knowledge about the importance and
impact of climatic change, warming the global, on chicken production, focusing on
chicken immunity. Chickens have very strong built-in defenses (immunity) against
diseases that are caused by overrunning of the body by various microorganisms
and toxins. Under stress conditions, avian blood tolerates a change from acid-base
balance to alkaline balance. There is a decline in the plasma, a reduced level of
vitamin C in the adrenal cortex, a reduction in lymphocytes, and a depression of
the immune response. As the temperature rises, the birds undergo many changes—
increased water consumption, respiration rate, body temperature, inferior egg quality,
and susceptibility to diseases.
The highly specific adaptive immune mechanisms are affected by heat stress.
In more specific, heat stress deteriorates the cell-mediated immune responses. As a
result of heat conditioning, biochemical and physiological mechanisms were induced
to cope with heat stress; this induction may have delayed production of additional
acute phase proteins to protect the cells from damage. The stress hormones—cytokine
interactions are responsible for altered immune functions during heat stress. Modernday molecular biology tools can help in understanding various cellular and molecular
mechanisms involved in the production, physiological and immunological aspects of
the poultry birds, which in turn can help in the development of breeds more adapted
to the climate changes.
3.5 Socioeconomic Impacts
The socioeconomic impacts of climate change are covered in three chapters. The
chapter titled “Climate Change, Agriculture, and Rural Communities’ Vulnerability
in the Nile Delta” discusses the severe impacts of climate change on agricultural
production and rural communities in the Nile Delta in Egypt. However, immediate
challenges, such as population growth, land fragmentation, and urban expansion on
agricultural land if not timely curbed will further exacerbate future climate change
impact. Agriculture in Egypt in general and in the Nile Delta in particular, is currently
facing other intense challenges resulting from the rapid population growth that is
exceeding 2.5% annually [13], thus augmenting agricultural land and irrigation water
scarcities.
Farmers in Egypt are expected to suffer from climate change impacts, and the
Nile Delta in the northern part of Egypt—comprising about 50% of the agricultural
land—is identified as one of the world’s three “extreme” vulnerability hotspots.