Иностранный язык (английский). Учебное пособие
.pdfThe abomasums is like the human stomach; this is why it is known as the “true stomach”.
Cattle are ruminants. They have a digestive system that allows use of otherwise indigestible foods by repeatedly regurgitating and rechewing them as “cud”. The cud is then reswallowed and further digested by specialized microorganismus in the rumen. These microbes are primarily responsible for decomposing cellulose and other carbohydrates into volatile fatty acids that cattle use as their primary metabolic fuel. The microbes inside the rumen are also able to synthesize amino acids from nonprotein nitrogenous sources, such as urea and ammonia. As these microbes reproduce in the rumen, older generations die and their carcasses continue on through the digestive tract. These carcasses are then partially digested by the cattle, allowing them to gain a high quality protein source. These features allow cattle to thrive on grasses and other vegetation. The gestation period for a cow is nine months. A newborn calf weighs 25 – 45 kg (55 to 99 lb). Breeding stock usually lives to about 15 years (occasionally as much as 25 years).
Vocabulary list
cattle pl. ['kætl] – крупный рогатый скот stomach ['stΛmək] – желудок
compartment [kəm'pa:pmənt] – отдел, отделение rumen ['ru:men] – рубец, первый отдел преджелудка
reticulum [ri'tikjuləm] – сетка, второй отдел преджелудка omasum – книжка, третий отдел преджелудка abomasum – сычуг, четвертый отдел преджелудка hardware [`ha:dwεə] – металические изделия
digestible – легко усваиваемый
ruminant ['ru:minənt] – жвачный, жвачное животное digestive – пищеварительный
carbo-hydrate ['ka:bəu'haidreit] – углевод nitrogenous – азотный, азотистый
urea ['ju:əriə] – мочевина ammonia ['əməunjə] – аммиак carcass ['ka:kəs] – туша, тело
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gestation – беременность stock – порода племя
I. Answer the following questions.
1.What are cattle raised for?
2.What organs form the digestive system?
3.What are the functions of the organs of digestion?
4.Are cattle ruminants?
5.How many years does breeding stock live?
UNIT 4.
DISEASES OF ANIMALS AND BIRDS
Classification of animal diseases
Disease is the general term for any deviation from the normal or healthy condition of the body. Diseases of animals are disorders which influence an animal’s health and ability to function. Animal diseases are of great concern to human beings for several reasons. Diseases can reduce the productivity of animals used to produce food, such as hens and dairy cows. Animals that are raised as food, such as pigs and beef cattle that become ill may affect the economic wellbeing of many industries. Some animal diseases can be transmitted to human beings, and control of these types of diseases, known as zoonoses, is vital to public health. In the wild animal popu lations reduced by disease can upset the ecological balance of an area. And, in the case of pets, prevention and treatment of animal diseases help pets live long and healthy lives, enhancing the companionship shared by a pet and its human owner.
Animal diseases are characterized as infectious and noninfectious. Infectious diseases are caused by an agent, such as bacteria or a virus that penetrates the body’s natural defense mechanisms, while noninfectious diseases are caused by factors such as diet, environment, injury, and heredity.
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Sometimes the cause of a disease is unknown. An animal may also experience one disease or a combination of diseases simultaneously. To identify a disease, a veterinarian (a doctor who treats animals) first determines the animal’s signalments — species, breed, age, and sex. This information helps to identify a disease because some diseases are more prevalent in certain species, or a disease may preferentially affect one sex or age group. Then the veterinarian gathers a complete history of the animal and its problem. This history includes the first symptoms which appeared in the animal. The veterinarian gives the animal a thorough physical examination, which may include measuring its body temperature, listening to its heart, checking its pulse, and feeling its abdomen and lymphnodes. Then the veterinarian creates a list of possible diseases that may make the animal sick. The list may be narrowed by running diagnostic tests such as X rays, electrocardiograms, blood analyses, and bacterial or fungal cultures.
Once the disease is identified, the doctor develops a treatment plan for the animal.
I. Answer the questions.
1.What is disease?
2.How can diseases affect the animal’s health?
3.How are animal diseases classified?
4.What diseases are caused by bacteria or a virus?
5.How does a veterinarian indentify a disease first?
6.What includes the history of the animal?
7.Once the disease is identified, what does a veterinarian do next?
II. Scan the text and complete the sentences.
1. Animal diseases are characterized ......
2. ......a veterinarian first determines the animal’s signalments. 3. ......help pets live long and healthy lives.
4.Some animal diseases can be transmitted to ......
5.Diseases of animals are disorders which influence ......
6.......are caused by an agent, such as bacteria or a virus.
7.......are caused by factors such as diet, environment and heredity.
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III. Choose the appropriate definition.
Disorder, zoonotic disease, a vet, disease, infectious diseases, treatment, bacteria
1.is an illness which affects people, animals, or plants.
2.are caused by an agent, such as bacteria or a virus.
3.is a problem or illness which affects a person’s or animal’s body.
4.is someone who is qualified to treat sick or injured animals.
5.is medical attention given to a sick or injured person or animal.
6.are small organisms which can cause disease.
7.can be transmitted to human beings.
Infectious diseases
Infectious diseases are those caused by an infecting agent or organism. A disease can be infectious but not readily transmitted to others. There are several categories of organism capable of infecting domestic animals. They include parasites, bacteria and viruses. Some of these diseases are transmissible from animals to human beings — these are known as zoonoses. Examples of zoonoses are rabies and tuberculosis. Some examples of important bacterial diseases of domestic animals are shown below.
Anthrax. Anthrax is caused by Bacillus anthracis and can affect all warmblooded animals. It is highly contagious to human beings handling an infected animal but it is not normally transmitted readily to other animals on the farm. Anthrax is usually rapidly fatal.
Brucellosis. Brucellosis is caused by several species including Brucella abortus. It commonly affects cattle, sheep, goats, pigs, human beings and causes abortion and fever. There is no effective treatment for affected animals. Human beings are normally treated with large doses of antibiotics for a very long period. Brucellosis can be effectively controlled by vaccination, combined with testing and eradication. It is fairly well controlled in livestock in the USA. There is concern about it spreading into cattle from other sources, e.g. buffalo.
Tuberculosis. Tuberculosis is caused by several species including Mycobacterium tuberculosis. It affects mammals, birds and
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reptiles. An effective treatment is available although drug resistance is becoming a serious problem for human beings. Tuberculosis requires a long course of therapy. Herds are tested regularly by veterinarians and if affected animals are found they should be slaughtered. Meat and milk of infected animals can transmit the disease.
Swine dysentery. Swine dysentery is caused by Treponema hyodysenteriae. The disease causes diarrhea and weight loss in young pigs. It is controlled by antibiotics in feed. Some vaccines are being developed.
Salmonellosis. Salmonellosis is caused by various species of Salmonella. There are typically two forms: an enteric form in which diarrhea and vomiting is present and young animals are mainly at risk of dehydration and an invasive form in which the bacteria of the Salmonella genus invade the bloodstream and cause septicaemia. The latter is often fatal. There are some vaccines against salmonellosis but they are of limited efficiency. Antibiotics and fluids are the usual treatments.
Mastitis. Mastitis is an infection of the mammary gland by various species of bacteria. It affects all mammals, reducing milk yield and quality. The disease is spread through contaminated equipment or hands of the milker and dirty barns and yards. The symptoms are clotted and watery milk, fever, pain, swelling and change in the shape of the udder. Preventive measures are hygiene and therapy. A vaccine is available to reduce incidence of coliform mastitis.
I. Scan the text to determine whether these statements are true (T) or false (F).
In my opinion it is true that …....../I’m afraid it is false that
…......because …......
To make it clear I’d like …....../It is my belief that .........
I agree with the point of view that …....../I really think .........
1.Infectious diseases are those caused by an infecting agent or organism.
2.Some diseases which are transmissible from animals to animals are known as zoonoses.
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3.A disease can be infectious and readily transmitted to others.
4.Meat and milk of infected animals can transmit swine dysentery.
5.Some important bacterial diseases of domestic animals are anthrax, mastitis, rabies.
6.Several categories of organism capable of infecting domestic animals include parasites, bacteria and viruses.
II. Read the description and guess what disease it is.
1.Causes abortion, fever. No effective treatment for affected animals.
2.Affects all mammals reducing milk yield and quality. The symptoms are clotted and watery milk, fever, pain, swelling and change in the shape of the udder.
3.Causes diarrhea and weight loss in young pigs.
4.Herds are tested regularly by veterinarian and affected animals slaughtered. Meat and milk of infected animals can transmit disease.
5.Diarrhea and vomiting are present and young animals are mainly at risk of dehydration; the bacteria invade the bloodstream and cause septicaemia.
III. Complete the sentences.
1. ...... is highly contagious to human beings.
2.Infectious diseases are those caused by an infecting ......
3.Some diseases which are transmissible from animals to human beings are known as ......
4.Some examples of important bacterial diseases of domestic animals are ......
5....... are the usual treatments.
6....... requires a long course of therapy.
Bird flu (avian influenza)
In people, bird flu usually begins like conventional influenza, with fever, cough, sore throat and muscle aches, but bird flu can lead to lifethreatening complications. Bird flu viruses are complex, with a number of subtypes and strains that vary considerably from one
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another. Among birds, the effects of low pathogenic viruses are usually ruffled feathers or reduced egg production. But highly pathogenic forms cause severe disease, and almost 100 percent mortality in susceptible species. In some cases, domestic birds may die when symptoms are appeared. Scientists dоn't yet know how these subtypes affect humans, but highly pathogenic viruses appear causing the most serious problems – the greatest number of deaths – in both people and animals. Although the exact incubation period for bird flu in humans isn't clear, illness is developed within one to five days. Sometimes the only indication of the disease is a relatively mild eye infection (conjunctivitis). But more often, signs and symptoms of bird flu resemble those of conventional influenza, including: cough, fever, sore throat, muscle aches.
Migratory waterfowl and ducks in particular carry the viruses that cause bird flu. Often unaffected themselves, the host birds can spread the infection to susceptible species, especially domesticated chickens, turkeys and geese, resulting in severe epidemics that kill large numbers of birds – sometimes in a single day. Direct bird-to- human transmission works like this: infected migratory waterfowl carry bird flu viruses, shed the virus in their droppings, saliva and nasal secretions.
Domestic poultry become infected from contact with these birdsor with contaminated water, feed or soil. They may also catch the disease by inhaling the airborne virus. Bird flu spreads quickly and lethally within a flock and is inadvertently transported from farm to farm on tractors and other equipment, on cages, and on workers' shoes and clothing. Heat destroys the virus, but it can survive for extended periods in cool temperatures. Open-air markets, where eggs and birds are often sold in crowded and unsanitary conditions, are hotbeds of infection and spread the disease into the wider community. Scientists don't think that migratory birds are carrying the virus from continent to continent because outbreaks haven't followed traditional flyways. Instead, outbreaks seem much more likely to spread locally through “wet markets”, contaminated clothing and equipment, and smuggled birds.
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Vocabulary list
bird flu ['bə:d 'flu:] – птичий грипп
conventional influenza [kən'ven∫nl "influ'enzə] – обычный грипп fever ['fi:və] – лихорадка, жар
cough – кашель sore throat – ангина
muscle ache – боль в мышцах ruffled – взъерошенный feather ['feðə] – перо mortality – смертность
death ['ðeθ] – смерть illness ['ilnis] – болезнь
infection [in'fekə∫n] – инфекция migratory ['maigrətəri] – мигрирующие waterfowl – водяные птицы
turkey ['tə:ki] – индейка geese ['gi:s] – гуси
infected [in'fektid] – инфицированные dropping – помет животных, навоз
nasal secretion ['neizəl si'kri:∫ən] – выделение носовой cекреции domesticated – одомашнивание
poultry ['pəυltri] – домашняя птица contaminated [kəntimi'neitid] – зараженный to inhale [in'heil] – вдыхать
to destroy – уничтожать
to survive [sə:'vaiv] – выживать hotbed – очаг
outbreak ['aυt'breik] – вспышка to smuggle – провозить тайно
direct bird-to-human transmission – прямая передача от птицы к человеку
I. Answer the questions.
1.What symptoms of bird flu do people have?
2.What symptoms of bird flu do the birds have?
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3.What birds carry the viruses that cause bird flu?
4.What birds can the host birds spread the infection to?
5.What way do infected birds shed the virus by?
6.How does domestic poultry become infected?
7.How is bird flu spread?
8.What destroys the virus?
9.What are hotbeds of infection?
10.What do scientists think about outbreaks of bird flu?
11.What treatment for bird flu do the birds have?
Salmonellosis
Salmonellosis is a bacterial disease caused by the bacterium Salmonella. More often it infects cattle of young age. Symptoms include fever, watery diarrhea, and cough. In some cases animals may die in 5–10 days. Salmonellosis affects lungs, and gastrointestinal system. Many different kinds of Salmonella can make people sick. Mоst people have diarrhea, fever, and stomach pain. These symptoms usually go away after one week. Sometimes, people have to see a doctor or go to the hospital if the diarrhea is severe or the infection has affected other organs.
Many kinds of animals can pass salmonellosis to people. Usually, people get salmonellosis by eating contaminated food, such as chicken or eggs. However, animals can carry Salmonella and pass it in their feces (stool). Therefore, people can also get salmonellosis if they do not wash their hands after touching the feces of animals. Reptiles (lizards, snakes, and turtles), baby chicks, and ducklings are especially likely to pass salmonellosis to people. Dogs, cats, birds (including pet birds), horses, and farm animals can also pass Salmonella in their feces. Some people are more likely than others to get salmonellosis. A person's age and health status may affect his or her immune system, increasing the chances of getting sick. People who are more likely to get salmonellosis include infants, children younger than 5 years old, organ transplant patients, people with HIV/AIDS, and people receiving treatment for cancer.
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Vocabulary list
salmonellosis – сальмонеллез to infect [in'fekt] – заражать severe [si'viə] – сильный
to affect [æ'fekt] – поражать
stool [stu:l] – стул, действие кишечника lizard ['lizəd] – ящерица
snake [sneik] – змея turtle ['tə:tl] – черепаха
immune [i'mju:n] – иммунный infant ['infænt] – ребенок patient ['pei∫ənt] – больной cancer ['kænsə] – рак
I. Answer the questions.
1.What disease is salmonellosis?
2.What cattle does salmonellosis infect more often?
3.What symptoms of the disease do the cattle have?
4.Can people get salmonellosis?
5.What symptoms do people have?
6.What should the patients do if they have salmonellosis?
7.How long are people ill?
8.What treatment do they have?
Cryptosporidium infection
Cryptosporidium infection (cryptosporidiosis) is a parasitic disease caused by Cryptosporidium parvum. It usually causes severe infection of the gastrointestinal system, including watery diarrhea, fever, abdominal cramps, nausea, and vomiting. Most people get Cryptosporidium infection from contaminated food and water. However, sometimes animals (including farm animals, cats, and dogs) carry this parasite in their feces (stool) and pass it to people. People with compromised immune systems, such as those undergoing immunosuppressive treatments for cancer, organ transplant patients,
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