Affected animals usually show a pronounced fall in milk yield caused probably by the sharp fall in volatile fatty acid production in the atonic rumen. Rumen contractions appear to play the same role as hunger contractions in simple stomachs and the decreased food intake is probably due to the ruminal atony.
Clinical Findings. A reduction in appetite is the first sign and is followed closely in milking cows by a slight drop in milk production. Both occur suddenly, the anorexia may be partial or complete but the fall in milk yield is relatively slight. The animal's posture is unaffected but there is mild depression and dullness. Rumination ceases and there is constipation with scanty, firm feces in most cases although diarrhea may occur on damaged feeds. Ruminal movements are depressed in frequency and force or are absent. There may be moderate tympany, especially with frozen and damaged feeds or in allergy but the usual finding is a firm doughy rumen without obvious distension.
There is no systemic reaction and the pulse, temperature and respiration rates are unaffected. Pain cannot be elicited by percussion of the abdominal wall. Most cases recover spontaneously or with simple treatments in about 48 hours. The disease is not a fatal one.
Secondary ruminal atony occurs in many diseases especially when septicemia or toxemia is present but there are usually additional clinical signs to indicate their presence.
Exercise 4. Read and translate the text B, determine the verb forms and their function and retell in English according next questions:
1 ?
2 ?
3
?
4 ?
5 ?
Lesson 16
A. Erysipelas in Swine
Erysipelas is an infectious disease, of pigs and appears in an acute, septicaemic form often accompanied by diamond shaped skin lesions and a chronic form manifested by a non-suppurative arthritis and a vegetative endocarditis.
Erysipelas in pigs occurs generally throughout the world.
Pigs of all ages are susceptible although adult pigs are most likely to be affected. Recently farrowed sows seem to be particularly susceptible. When the strain is virulent pigs of all ages, even sucklings a few weeks old, develop the disease. Immune sows are capable of giving sufficient antibodies in the colostrum to their piglets for some weeks.
Soil contamination occurs through the faeces of affected or carrier pigs. Other sources, of infection include infected animals of other species, and birds. Since the organism can pass through the stomach without losing viability, carrier animals are capable of re-infection the soil continuously. The organism is highly resistant to most, environmental influences and is not readily destroyed by chemical disinfection.
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Vocabulary List
erysipelas (n) - , accompany (v) -
diamond (n) - , suppurative (a)
vegetative endocarditis - adult (a) -
recently (adv) - farrow (v) -
sow (n) - , particularly (adv) -
strain (n) - virulent (a) - ,
suckling (n) - sufficient (a) -
colostrum (n) - piglet (n) -
contamination (n) - ,
faeces (n) pl - , carrier (n) -
source (n) - since (cj) - ,
through (prep.) - lose (v) (lost) -
viability (n) - destroy (v) -
continuous (a) - environmental (a) -
influence (n) - readily (adv) - ,
Exercise 1. Read the text "Erysipelas in Swine" Part A, answer the following questions to the text in Russian:
1. What are the symptoms of erysipelas?
2. Animals of what ages are most susceptible to the disease?
Exercise 2. Answer the questions in Russian and then in English:
1. What are the forms of erysipelas?
2. Where does erysipelas occur?
3. Are recently farrowed sows susceptible to the disease?
4. When do sucklings develop the disease?
5. How does soil contamination occur?
6. Why do carrier animals re-infect the soil continuously?
7. Is the organism resistant to most environmental influences?
Exercise 3. Translate the text Part A into Russian.
B. Erysipelas in Swine
Clinical Findings. Acute form. After an incubation period of 1 to 7 days there is a sudden onset of high fever (up to 108F or 42 C) which is followed some time later by severe prostration, ' complete anorexia, thirst and occasional vomiting. Initially, affected pigs may be quite active and continue to eat even though the temperature is high. A marked conjunctivitis with profuse ocular discharge may be present. Skin lesions are almost pathognomonic but may not always be apparent. These may take the form of the classical diamond-shaped. After a course of 2 to 4 days the pig recovers or dies with diarrhoea, dyspnoea and cyanosis evident terminally. The mortality rate is capable of reaching 75 per cent but wide variation occurs.
The so-called "skin" form is usually the acute form with more prominent skin localization but less severe signs of septicemia and with a low mortality. The skin lesions disappear in about 10 days without residual effects.
Chronic form. Signs are vague and indistinct except for the joint lesions characteristic of this form of the disease. There may be alopecia, sloughing of the tail and tips of the ears, and a dermatitis in the form of hyperkeratosis of the skin of the back, shoulders and legs.
The joints are obviously enlarged and are usually hot and painful at first but in 2 to 3 weeks are quite firm and without heat. This is especially the case when the arthritis has been, present for some time, allowing healing and ankylosis to develop. Endocarlitis also occurs as a chronic form of the disease with or without arthritis.
Exercise 4. Read and translate the text B into Russian.
Exercise 5. Render the contents of the text "Erysipelas in Swine" Part B answering the following questions:
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1.
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2. ?
3. ?
4. ?
5.
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6. ?
Lesson 17
A. Listeriosis
Listeriosis is known to be an infectious disease caused by Listeria monocytogenes and characterized by either meningo-encephalitis, abortion or septicaemia. The disease is of greatest economic importance in sheep and cattle. In man the disease is serious and often fatal. Animals of any age, including the newborn, may be affected in a herd, the infection rate reaching 10 per cent. The mortality rate without treatment in listerial septicaemia and listerial meningo-encephalitis approaches 100 per cent.
List, monocytogenes is the causative organism and can be isolated in pure culture from affected animals. Several strains of the organism have been identified.
Sheep, cattle, buffalo, goats, horses, pigs, cats, rabbits and some wild animals and man are susceptible to infection. One can expect to find the meningo-encephalitic form and the visceral form (chiefly as abortion or neonatal septicaemia) in different outbreaks of the disease, and rarely two forms together in the one outbreak.
Vocabulary List
newborn () -
approach (v) -
buffalo (n) -
neonatal () -
Exercise 1. Read the text "Listeriosis" Part A and answer the following questions to the text in Russian:
1. What are the symptoms of listeriosis?
2. What animals are susceptible to infection?
Exercise 2. Answer the following questions on the text A in Russian and then in English:
1. Is listeriosis known to be an infectious disease?
2. What is the cause of listeriosis?
3. Has the disease an economic importance in sheep and
cattle?
4. What is the mortality rate without treatment?
5. Is it possible to isolate the causative organism of the
disease?
6. Is it possible to find two forms of listeriosis in one outbreak?
Exercise 3. Translate the text Part A into Russian.
B. Listeriosis
Listerial meningo-encephalitis. This form has been observed in all species and presents a standard syndrome. In adult cattle the course of the disease is usually 1 to 2 weeks but in sheep and calves the disease is more acute, death occurring in 3 to 4 days. Basically the clinical picture combines the signs of the dummy syndrome, with pressing against fixed objects, and unilateral facial paralysis. Affected animals are dull, often at the point of somnolence, and isolate themselves from the rest of the group. Prehension and mastication are slow and the animal stands for long periods drooling saliva and with food hanging from its mouth. The affected animals become recumbent and are unable to rise. Death is due to respiratory failure. Fever (usually 104 F or 40 C, but occasionally as high as 107 F or 42 C) is usual in the early stages of the disease but the temperature is usually normal when frank clinical signs are present.
Listerial abortion. In cattle many sporadic abortions due to List, monocytogenes are recorded and outbreaks of abortion due to this organism are recorded in cattle, sheep and in goats.
Septicaemic listeriosis. Acute septicaemia due to List, monocytogenes is not common in adult ruminants but does occur in monogastric animals including foals, young pigs and newborn lambs and calves. There are no signs suggestive of nervous system involvement, the syndrome being a general one comprising depression, weakness, emaciation, pyrexia and diarrhoea in some cases, with hepatic necrosis and gastroenteritis at necropsy.
Vocabulary List
dummy syndrome
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often to the point of somnolence
respiratory failure
Exercise 4. Read and translate the text "Listeriosis" Part B
using a dictionary.
Exercise 5. Retell the text Part B answering the following questions:
1. -
?
2.
?
3. ?
4. ? ?
5.
, ?
6.
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7. ?
8. -
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Supplement
A. Veterinary Science
Veterinary Science is also called veterinary medicine and includes the prevention, diagnosis, and treatment of the diseases of domestic animals and the management of other animal disorders. The field also deals with those diseases that are intercommunicating between animals and humans.
Persons who serve as doctors to animals have existed since early times, and veterinary practice was already established as a specialty as early as 2000 in Babylonia and Egypt and the ancient Greeks had "horse-doctors". The first veterinary schools in Europe were established in the mid-18th century and since that time veterinary science has rapidly developed alongside with modern medicine.
Animal health is to ensure the efficient production of whole some animal products. Farm animals are susceptible to various infectious diseases and may suffer from viruses and harmful bacteria, so animals should be examined by veterinary surgeons regularly in order to notice disease symptoms in time and take the necessary preventive and control measures. Such common animal diseases as mastitis, brucellosis, swine fever, erysipelas, anthrax, and leptospirosis can quickly spread and cause major losses among stock animals, so they must be controlled or prevented by veterinary surgeons.
Vaccination and immunization, sanitary measures, and the severe segregation, or quarantine, of sick animals should be used by farmers and veterinary surgeons to prevent the spread of infectious diseases such as anthrax, bovine tuberculosis, brucellosis, canine distemper, and rabies. Sanitary control of animal housing and proper pasture management are to eliminate any carriers of animal infectious diseases which can be easily transmitted by water and soil.
The government officials must be informed about the outbreak of a notifiable disease in order to prevent the disease spread. If an animal has contract the infectious disease and cannot be cured, it will have to be slaughtered.
Veterinary surgeons also treat parasitical infections, unsanitary conditions which may cause lower fertility in livestock, and nutritional disorders and they often have to set broken limbs and neuter domestic pets. Besides, veterinary scientists investigate the chronic infectious diseases associated with high morbidity rates and various metabolic disorders. The development of vaccine to control Marek's disease in chickens is an example of the economic effect of animal-disease research that was conducted by veterinary scientists.
Vocabulary List
intercommunicable .
alongside with
to set broken limbs .
to neuter
morbidity rate
B. Veterinary Science
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A veterinary surgeon's training must include the study of the basic preclinical disciplines of anatomy, histology, physiology, pharmacology, microbiology as well as bacteriology, virology, parasitology, and pathology. The clinical subjects of study may be divided into internal medicine, preventive medicine, surgery and clinical practice.
Internal medicine includes the diagnosis and treatment of diseases as they affect animals. Preventive medicine should consider the aspects of disease prevention and control, especially such diseases that can be transmitted between animals and humans or diseases that may influence human health. Generally, several preventive techniques are available for the use in the prevention of disease in an animal population such as quarantine, immunisation, environmental control, various methods of disease control and eradication, early diagnosis of a disease. It has been proved that animal diseases may be prevented to a great extent by ensuring proper hygienic and sanitary conditions on a farm, which include the maintenance of safe water supplies, air sanitation, pest control, the improvement of animal housing etc. Surgery includes wound treatment, fracture repair, the excision of body parts, and the use of such techniques as radiology, anesthesiology, obstetrics, treatment of lameness etc. In most veterinary schools, clinical practice enables students, especially future veterinary surgeons, to observe and assist with actual cases of disease or other conditions which require attention. In both medical and surgical treatment, the same techniques are to be used as in medical practice on humans.
In most countries of the world, professional veterinary surgeons must complete a special educational programme. According to this programme students are to study for four or six years at the university and only after such a course of study the degree of doctor of veterinary medicine is to be awarded. Moreover, in many countries veterinary surgeons must obtain a licence to start their practice from some duly constituted authority. Veterinary surgeons may specialize either in the care of small animals such as pets and work in banian hospitals, while others may treat mainly livestock. A few veterinary surgeons may be employed by zoos or circuses to examine and take care of wild animals.
There exist different international organisations such as the World Veterinary Association (WVA), the World Veterinary Association for Small Domestic Animals (WSAVA), the European Veterinary Association for Small Domestic Animals (FECAVA), as well as national organisations, for example, the American Veterinary Medical Association (AVMA), The Russian Association of General Veterinary Practitioners and the British Small Animal Veterinary Association (BSAVA) etc. Their purpose is to advance Veterinary Science and Veterinary Medical Profession, to hold conferences or seminars on veterinary problems.
Vocabulary List
wound treatment
fracture repair
excision obstetrics
lameness
duly constituted authority
Animal Husbandry
Agriculture provides people with food, feed and other useful products. All over the world farmers cultivate valuable plants and raise productive domesticated animals. There are two main branches in modern agriculture: crop production (or crop farming) and animal husbandry (or animal farming).
Nowadays, in many countries people are still relying on meat, milk and eggs as main sources of food. Both breeders and farmers have already bred and are still breeding highly productive agricultural animals. Animal farming is a process in which a farmer breeds, raises and cares for livestock either for commerce or private use.
The word "livestock" refers to domesticated animals such as beef and dairy cattle, sheep, goats, swine (hogs), horses, donkeys and mules, buffalo, oxen, rabbits or "exotic" animals, for example, camels, emus, ostriches, or any animal which a farmer keeps and uses either for food or pleasure. Sometimes animal scientists include in this term also poultry, such as chickens, ducks, geese and turkeys, but they include neither honey bees nor fish within the term "livestock". However, poultry farming and beekeeping are important branches of agriculture as well as aquaculture.
There are over a hundred large land mammals in the world but man has domesticated only few types into livestock. There are two main requirements for domestication of mammals: 1) the availability of feed which a farmer can easily control and provide; 2) a rapid rate of reproduction. As cattle, sheep and horses are herbivorous mammals, farmers try to keep these domestic animals on pastures. However, farmers often grow either cereals or other agricultural crops as additional feed for their animals. Such ruminant animals as cattle, sheep and goats are important for people because they convert large quantities of grasses or other types of feeds, as well as non-protein nitrogen into meat, milk and wool. Poultry also convert feed efficiently into protein.
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Historically, livestock and poultry have provided the following benefits to humanity: meat, eggs, dairy products, raw materials, fertiliser, labour, management of land.
1) Meat and eggs. In many countries livestock replaced wild game
as the main source of animal protein because only livestock convert various food sources into human food. Poultry provide people with white meat as well as with eggs.
2) Dairy products. People process milk of cows, sheep and goats into a variety of valuable dairy products such as yoghurt, cheese, butter, ice cream, kefir, and koumiss.
3) Raw materials. Livestock produce useful raw materials, for
example, horses and cows provide leather, poultry produce feather and down, sheep and goats provide wool for textile industry.
5) Fertiliser. Livestock leave behind manure which farmers spread on fields and this increases yields of crops many times. Historically, plant and animal farming have been closely linked. Labour. In modern agriculture neither cattle nor horses are the main source of mechanical energy. However, in some poor countries people are still using livestock as draft cattle.
6) Management of land. Sometimes farmers use the grazing of livestock as a way to control weeds.
When a farmer is planning to rear livestock, he usually chooses the most suitable type for the local conditions. Both climate and type of land, as well as local traditions influence a farmer's choice.
Vocabulary List
aquaeulture
availability ()
a rate of reproduction .
the following benefits to humanity
management .
wild game
feather, down ,
a way to control weeds
Exercise1. Answer the following questions:
1. What are the two main branches of agriculture?
2. Why is animal husbandry so important now?
3. What does the term "animal husbandry" include?
4. What are the requirements for domestication of animals?
5. Why are ruminant animals valuable for animal husbandry?
6. Why is poultry farming an important branch of agriculture?
7. What herbivorous animals do you know?
8. What benefits do livestock and poultry provide for man?
9. How does a farmer choose the type of livestock for his farm?
Exercise2. Think and answer:
1. In what countries does the agricultural sector play the most important role in the economy: in developed countries (the USA, Canada and the UK) or in developing African/Asian countries?
2. What industries does animal husbandry provide with raw materials?
3. What branches of agriculture are important in Russia?
