Basic Concepts In Economic Zoology
Economically Harmful and Useful Animals

Economic Zoology
Combination of two words = Eonomic+Zoology
Economics:
“Study of resources and expenditures of a country.”
Zoology:
“Study of structure, physiology, development and classification of
animals.”
Economic Zoology:
“Deals to minimize harmful effects of animals and to enhance their
useful effects in the society to improve our living by getting
benefits from them.”
Significance of Economic Zoology:
• Animals are good source of food (meat,milk,egg,sea food)
• Animals are useful for livestock and domestic purposes e.g cattle,
sheep, pigs, goats, horses, donkeys, and mules; other animals, such
as buffalo and camels for agricultural purposes.

Economically Useful Animals:
1. Cattle
• Make up the largest livestock group worldwide. Among those
prominent in beef and milk production .
• Cattle are sometimes used as draft animals, particularly in
small-scale farming and in less developed regions.
• The most widely consumed meat is beef, the flesh of
mature cattle that normally weigh from 450 to 540 kg
and yield between 55 and 60 percent of their weight in meat.
2. Pigs
• Have been raised for their meat (pork) since ancient times.
• For other marketing purposes as lard, bacon, or pork.
• The pig is the world’s second largest provider of meat. When
taken to slaughter, pigs generally weigh between 90 and 135
kg and provide about 70 to 74 percent of weight in meat.

3. Sheep
• Were among the first animals to be domesticated.
• Sheep are raised for the fleece or wool, meat (mutton and
lamb) and to a lesser degree for milk.
• Meat from lambs and sheep is produced on a much smaller
scale than either beef or pork.
4. Goats
• Are raised for their milk , meat, and to make leather and wool.
5. Horses
• First intensively domesticated in Central Asia, are bred not only
as livestock but also for riding, show, and racing.
6. Donkeys
• Donkeys and mules , the hybrids formed by crossbreeding a
male donkey and a female horse, are used as work animals for
farming, transportation and to obtain by-products.

Other By-Products
1. Pearls:
• Pearls are made by living creatures called
mollusks mainly marine oysters and freshwater
mussels.
• Mollusks commonly have a soft, un-segmented
body and a hard exterior shell, such snail
• These animals live in marine and freshwater
habitats as well as on land.
• Pearls are used for ornamental purposes mainly
jewelry.

2. Gelatin:
• An insulating layer of fat under the skin of
whales and other large marine mammals or
other terrestrial animals such as pig, bear etc
are used as a source of oil.
• Gelatin is a collagen protein, a translucent,
colorless, flavorless food ingredient,
commonly derived from animal body parts by
boiling skin, tendons, ligaments, and/or bones
with water. It is usually obtained from cows or
pigs.
• Used in cosmetics, baking, paints etc

3. Musk:
• It was a name originally given to a substance
with a strong odor obtained from a gland of
the male musk deer.
• The substance has been used as a popular
perfume fixative since ancient times and is
one of the most expensive animal products in
the world.
• They include glandular secretions from
animals such as the musk deer.
4. As decomposers of debris and recycling of
essential substances to the environment.

Economically Harmful Animals:
Some common diseases caused by animals.
• Snakes.
• Dogs (rabies) (Kills 59,000 per year)
• Assassin Bugs (Chagas disease) (Kills 10,000 per year)
• Scorpions. (Kills 3,300 humans per year)
• Crocodiles. (Kills 1,000 humans per year)
• Elephants. (Kills 600 humans per year)
• Hippos. (Kills 500 humans a year)
• Lions. (Kills 200 humans per year)
• Ascaris roundworms (2,500)
• Tapeworms (2,000)

Economically Harmful Animals:
1. Foot and mouth disease (FMD): (Viral disease)
• It is a severe, highly contagious viral disease of
livestock that has a significant economic impact.
• The disease affects cattle, swine, sheep, goats
and other cloven-hoofed ruminants.
• Affected animals have a high temperature, which
is followed by the development of blisters chiefly
in the mouth and on the feet.

Signs of Foot and Mouth in Cattle
• slobbering and smacking lips
• shivering
• tender and sore feet
• reduced milk yield
• sores and blisters on feet
• raised temperature

2. Chagas disease: (Parsitic disease)
• Chagas disease is an inflammatory, infectious disease
caused by the parasite Trypanosoma cruzi.
• This parasite is found in the feces of the triatomine
bug. This bug is also known as the "kissing bug.“
• These insects can become infected by this parasite
when they swallow blood from an animal that is
infected with the parasite.
Transformation to Humans:
• The parasites can then enter your body through your
eyes, mouth, a cut or scratch, or the wound from the
bug's bite.

• Eating uncooked food contaminated with feces
from bugs infected with the parasite.
• Getting a blood transfusion or an organ
transplant from someone who was infected with
the parasite.
• Being accidentally exposed to the parasite while
working in a lab.
• Spending time in a forest that contains infected
wild animals, such as raccoons and opossums.

Acute phase
• The acute phase of Chagas disease, which lasts for weeks or
months, is often symptom-free. When signs and symptoms do
occur, they are usually mild and may include:
• Swelling at the infection site
• Fever
• Fatigue
• Rash
• Body aches
• Eyelid swelling
• Headache
• Loss of appetite
• Nausea, diarrhea or vomiting
• Swollen glands
• Enlargement of your liver or spleen

In some cases, if the infection isn't treated, Chagas disease will
advance to the chronic phase.
Chronic phase
• Signs and symptoms of the chronic phase of Chagas disease
may occur 10 to 20 years after initial infection, or they may
never occur. In severe cases, Chagas disease signs and
symptoms may include:
• Irregular heartbeat
• Heart failure
• Sudden cardiac arrest
• Difficulty swallowing due to enlarged esophagus
• Stomach pain or constipation due to enlarged colon

3. Anthrax: (Bacterial disease)
• Anthrax Anthrax, a highly infectious and fatal disease of
cattle, is caused by a relatively large spore- forming
rectangular shaped bacterium called Bacillus anthracis
Symptoms:
• Very occasionally some animals may show trembling, a
high temperature
• Difficulty breathing, collapse and convulsions before
death.
• After death blood, may not clot, resulting in a small
amount of bloody discharge from the nose, mouth and
other openings

4. Rabies (Viral Disease):
• Rabies is a dangerous virus that causes brain
inflammation in humans and other mammals. Animals
carrying the infection can spread rabies to human
through bites and scratches.
• Rabies virus gets into your body when the saliva (spit)
of an infected animal gets into an open wound (usually
from a bite).
• It moves very slowly along nerves into your central
nervous system (your brain and spinal cord). When it
reaches your brain, the damage causes neurological
symptoms. From there, rabies leads to coma and
death.

Symptoms of rabies
• Fever.
• Tiredness (fatigue).
• Bite wound burning, itching, tingling, pain or numbness.
• Cough.
• Sore throat.
• Muscle pain.
• Nausea and vomiting.
• Diarrhea.
Neurological symptoms of rabies
• Neurological symptoms of rabies are either furious or
paralytic. Furious rabies symptoms may come and go with
periods of calmness in between.