CAPÍTULO 1: FUNDAMENTACIÓN TEÓRICA
1.4 Tecnologías para el desarrollo de Interfaces Web
1.4.1 Tecnologías del lado del cliente
(see LABORATORY TESTS)
Diaphoresis
Diaphoresis is another name for perspiration (see SWEAT).
Diaphoretics
Diaphoretics are remedies which promote perspiration.
Diaphragm
Diaphragm is the muscular and tendinous struc-ture which separates the chest from the abdom-inal cavity in mammals. It is an important organ in respiration. (See MUSCLES.)
Diaphragmatocele
A rupture in the diaphragm through which some of the abdominal organs, often the small intestine, stomach, and perhaps spleen and liver, have obtruded themselves, so that they become situated actually within the chest cavity. It occurs during falls, when jumping from a great height, and sometimes in cats and dogs hit by a car. The breathing becomes very much disturbed and the animal usually shows an inclination to assume an upright position, whereby the organs are encouraged to return to the abdominal cavity and pressure on the lungs is relieved. Treatment by surgical means has occasionally been effected in the dog and cat. (See THORACOTOMY.)
Diarrhoea
Diarrhoea is not, of course, a disease in itself, but merely a symptom, which may indicate nothing more than the result of an ‘error of diet’, or a ‘chill’. A sudden change of diet, or the feed-ing of unsuitable, mouldy, rancid, or fermentfeed-ing material will give rise to diarrhoea – a symptom of enteritis, and also of specific diseases in which enteritis is one symptom. Some drug treatments can also cause diarrhoea as a side-effect.
Continuing diarrhoea is always serious because not only are the digestive processes and the absorption of nutrients impaired, but the loss of fluid gives rise to DEHYDRATION– a fre-quent cause of death unless treatment is under-taken in time. If diarrhoea persists for 48 hours or more, veterinary advice should be sought by livestock-owners.
Other causes include poisons such as lead, arsenic and mercury; infection with tuberculosis in some part of the bowel wall; the presence of parasites such as worms, flukes, or coccidiae;
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infection with specific diseases, such as Johne’s disease, salmonellosis, lamb dysentery, white scour, etc.; or the excessive action of purgatives given in too large doses. In all of these instances there are other symptoms which help in the diag-nosis of the condition, and examination of the diarrhoeic material will often show the presence of the agent responsible (see SALMONELLOSIS).
Treatment
The treatment of diarrhoea from specific causes is dealt with under the appropri-ate headings. (See also WORMS, FARM TREATMENT AGAINST.)If diarrhoea persists, the mere loss of large amounts of fluid from the body may itself become serious, and it becomes essential to replace this fluid. (See under DEHYDRATION.)
Irrigation of the bowel with warm saline is useful in some cases of severe diarrhoea in puppies.
Adult cattle The best first-aid measure is to feed hay only. If ‘scouring’ persists beyond 48 hours, obtain veterinary advice. Specific dis-eases in which diarrhoea is a symptom include
AMYLOIDIOSIS; FASCIOLIASIS; JOHNE’S DISEASE;
SALMONELLOSIS; PARASITIC GASTROENTERITIS;
TUBERCULOSIS; CRYPTOSPORIDIOSIS; BOVINE VIRAL DIARRHOEA.
CalvesNeonatal diarrhoea is still regarded as the most important disease of young calves in both dairy and beef herds. Mortality varies widely from 0 to 80 per cent, and in non-fatal cases the resultant poor growth-rate and the cost of life-saving treatment can be a source of considerable loss to the farmer.
The causes are various. Although pathogenic strains of E. coli are important in the septicaemic and enterotoxaemic forms of the disease, there is doubt concerning the role of E. coli in all outbreaks of typical calf scours.
Of the many other bacteria which have been associated with the disease, few – with the exception of salmonella – can be shown to be the cause.
For viruses associated with diarrhoea in calves,
see ROTAVIRUS; CORONAVIRUSES; REOVIRUS. The coronavirus was originally isolated from scouring calves in Nebraska, USA, and shown to be present also in the UK. This virus resem-bles that causing transmissible gastroenteritis of pigs (TGE). (See also WHITE SCOUR; SALMONEL-LOSIS; COLOSTRUM.)
SheepLamb dysentery, E. coli infection, coc-cidiosis, parasitic gastroenteritis, salmonellosis, poisoning, and a sudden change to grain
feeding are among the causes of diarrhoea.
(See also JOHNE’S DISEASE; WORMS, FARM TREATMENT AGAINST; SOIL-CONTAMINATED HERBAGE; CAMPYLOBACTER; COCCIDIOSIS;
COPPER, POISONING BY; ROTAVIRUS.)
PigsThe causes are numerous and include: iron deficiency; high fat content of sow’s milk at about the 3rd week; stress, caused by e.g. long journeys; cold, damp surroundings; change of diet; vitamin deficiencies; poisons; transmissible gastroenteritis (TGE), swine dysentery, porcine intestinal adenomatosis and other disease.
Viruses responsible include coronavirus and rotavirus. Bacteria include E. coli (some strains), Campylobacter, Salmonella cholerae suis, S. dublin, Clostridium welchii, Erysipelothrix rhusiopathiae (the cause of erysipelas); also protozoa, e.g.
Balantidium coli, coccidia; fungi; yeasts; worms.
E. coli is regarded as being associated with a high proportion of outbreaks of scouring, though it can be obtained from the gut of virtually any healthy pig. Its precise importance and roles are explained under E. COLI. E. coli vaccines have been administered to sows before farrowing on farms where scouring is a problem. (See also K88 ANTIGEN.)
Scouring piglets need plenty of drinking water, for there is always danger of DEHYDRA-TION. (See also SWINE DYSENTERY; SOW’S MILK;
SWINE FEVER; ILEUM; NECROTIC ENTERITIS.) Dogs Diarrhoea may be associated with a number of infections, distemper, toxoplasmo-sis, tuberculotoxoplasmo-sis, nocardiosis; occasionally with pyometra; with allergies; tumours; and poisoning.
Diarrhoea may also result from an infestation of dog biscuits or meal, stored in large bins, by flour/forage mites (see FLOUR MITE INFESTA-TION). (See also SALMONELLOSIS; E. COLI; STRESS;
PANCREAS; WORMS; CANINE PARVOVIRUS;
CAMPYLOBACTER; ROTAVIRUS; YERSINIOSIS;
GIARDIASIS.)
Chronic diarrhoea is sometimes caused by Clostridium difficile. Metronidazole has proved useful in treatment, though relapses may occur.
CatsSimilar causes (except distemper) apply. (See also FELINE INFECTIOUS ENTERITIS; FELINE INFEC-TIOUS PERITONITIS; COCCIDIOSIS; AEROMONAS;
CORONAVIRUSES.)
HorsesClinical evidence has suggested a possi-ble association between diarrhoea, stress, and antibiotic therapy. For example, a horse which is undergoing stress and happens to be a salmonella carrier may develop diarrhoea, and this may Diarrhoea 183
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be exacerbated by tetracycline therapy which removes normal bacterial antagonists of the salmonella. Diarrhoea may, of course, be unasso-ciated with stress, and among the many other causes is ulceration of the colon and caecum – probably caused by the thrombo-embolism associated with migrating larvae of the worm Strongylus vulgaris. (See also FOALS, DISEASES OF;
SALMONELLOSIS; EQUINE INFECTIOUS ANAEMIA;
EQUINE VIRAL ENTERITIS; HORSES, WORMS IN;
GLOBIDIOSIS; CANCER; and POTOMAC HORSE FEVER.)
Whenever an apparently simple diarrhoea lasts for more than 1 or 2 days, it is wise to seek professional advice rather than attempt what must at best be only empirical treatment. The temperature is a useful guide to the severity of the condition, especially in young animals such as foals and puppies, and in all cases where it is high it is an indication that there is some serious condition complicating the diarrhoea which demands immediate attention.
Diastema
A gap between the front and cheek teeth in ruminants.
Diastasis
Diastasis is a term applied to separation of the end of a growing bone from the shaft.
Diastole
Diastole means the relaxation of a hollow organ. The term is applied in particular to the heart, to indicate the resting period that occurs between the beats (systoles) while the blood is flowing into the organ.
Diathermy
Diathermy is a process by which electric cur-rents can be passed into the deeper parts of the body so as to produce internal warmth and relieve pain, or, by using powerful currents, to destroy tumours and diseased parts bloodlessly.
Short-wave diathermy has been used in the treatment of muscle, tendon, and ligament strains. In horses with e.g. flexor-tendon trou-ble, 20-minute treatments over a period of a week may be effective.
Diazepam
A tranquilliser used in the treatment of epilep-sy and some abnormal behaviours in the dog.
Valium is a proprietary name.
Diazinon
An organophosphorus compound used in dips for sheep scab and other ectoparasites.
Diazinon granules are used for the control of wireworms on lawns and larger areas of grass-land. If applied too liberally there is a risk of poisoning to birds, and also to young cattle.
In a case involving ornamental peafowl, adult birds fell forwards on to their chests, with legs stretched out behind when attempting to walk. Some could not walk at all. Diarrhoea and dyspnoea were evident. Sick birds remained alert but refused food. Two young birds were found dead; the ill adults recovered without treatment.
Dichlorophen
A drug of value against tapeworms in the dog. Dichlorophen ointment and a spray preparation have been used in the treatment of ringworm in cattle.
Dichlorvos
An organophosphorus insecticide and parasiti-cide used in a range of internal and external applications. For example, it has been used against fowl mites on laying hens and turkeys, and as an aerosol for treating flea infestations in cats and dogs. Strips of resin impregnated with dichlorvos have been used successfully for the control of dog and cat fleas, over a period of 3 months or so. (See FLEA COLLARS.) However, in common with other organophosphorus compounds dichlorvos must be used with care to avoid toxicity. In the UK the sale of products containing it is restricted.
Poultry have died after gaining access to the faeces of horses dosed with dichlorvos for anthelmintic purposes. Dichlorvos is effective against horse bots as well as round worms.
Diclazuril
A drug used for the treatment and prevention of coccidiosis in turkeys, meat-producing chickens and lambs.
Dicoumarol
Dicoumarol is chemically related to WARFARIN; it is an anti-coagulant and a cause of internal haem-orrhage. The latter condition may develop after cattle have eaten mouldy hay containing sweet vernal or sweet clovers, the COUMARINcontent of which has been converted to dicoumarol.
Dicrocoelium
(see under LIVER-FLUKES)
Dicrotic
Dicrotic pulse is one in which at each heartbeat, 2 impulses are felt by the finger that is taking the pulse. A dicrotic wave is normally present 184 Diastema
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in a tracing of a pulse as recorded by special instruments for the purpose, but in health it is imperceptible to the finger.