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Poultry-farming constitutes a distinct branch of animal husbandry and there are many farms specially going in for the breeding of domestic fowl. Hens, geese, ducks and turkeys are bred here. The modern method of hatching chicks is not so much letting the hen brood on the eggs, but mostly to use incubators, which proves far more efficient. Feeding hoppers have also become regular poultry-farm practice, finding much the same application as in stock-sheds, piggeries, etc.
Poultry is partly bred for meat, down and feathers, but, above all, for eggs.
Eggs represent a cheap source of high quality protein for human consumption. The modern poultry industry producing eggs includes the use of specially bred birds, highly specialized feeds together with new housing and management techniques.
Efficient chicken production is one of the cheapest and most economical means of producing highly nutritious tender lean meat. Over the past decade improvements in performance and efficiency have been substantial.
The stock available to the chicken industry is selected particularly for high growth rate and survival capacity. They are further characterized by their attractive carcass conformation and a high meat-bone ratio.
For efficient control and economy in operation everything is fully integrated so that the activities of chicken breeding units, hatcheries, chicken (meat) producing units and processing stations are maintained in effective balance.
In addition, the feeding stuff requirement of an industry with a defined volume of output can be accurately planned on a long term basis.
To-day well-managed egg farms consistently achieve very high outputs.
A modern poultry farm comprises the following sections:
1) breeding units where the chicks are bred; 2) hatcheries where day-old pullets are obtained; 3) broiler production and rearing units, or 4) egg-laying units for laying hens; 5) stations for the disposal of breeders at the end of the laying cycle. Attached to the whole installation, there must also be a feeding stuff compounding mill for preparing the feed which, besides grain, proteins and vitamins, may also contain poultry offals.
The correct implementation of a proper technique enables layers to be kept all the year round, thus ensuring an even supply of eggs at all times. Also by keeping the birds in an environment conducive to the efficient utilization of the layer food, the bird is allowed more nearly to reach its genetic potential.
Some other branches of animal husbandry are: reindeer- breeding, rabbit-breeding, camel-breeding and, of course, horse-breeding at studs, though the use of horses and other types of draft cattle is being to a certain extent discontinued, tractors doing most of the work on the fields.
Not quite of secondary importance is apiculture, since, besides yielding honey and wax, it also contributes to pollination.
Text 13. FISHING
Britain is one of Europe's most important fishing nations. The fishing industry provides about 70 per cent of British fish supplies, and is an important source of employment and income in a number of ports (Hull, Grimsby, Milford Haven, Aberdeen, etc.). Cod accounted for 32 per cent of the total value of fish landed, while haddock (20 per cent), mackerel (10 per cent) and plaice (7 per cent) were the other most important sources of earnings to the industry.
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Some 73 per cent of the British catch is taken by the 7,100 vessels of the inshore fleet employing a variety of catching methods. The deep-sea fleet, comprising 245 larger vessels, has been reduced in number as fishing opportunities and the profitability of operations in distant waters have declined.
Since 1977 Britain's fishery limits have extended to 200 miles. Member states of the European Community have the right to fish up to Britain's 12-mile limit (some community countries may also fish in certain areas of Britain's 6-to 12-mile zone). With the extension of fishery limits to 200 miles, new arrangements became necessary to control Community fishing in the greatly extended area. Britain has a particularly strong interest in such control, since a sizeable proportion of the total catch within the 200-mile limits of member states is taken in British waters, while the loss of fishing opportunities in distant waters (such as Iceland) has reduced the British industry's total catch more than that of other Community states. As a result, Britain is looking for adequate access arrangements and a fair share of the quotas proposed for the fish stocks around its coasts and in other countries' waters.
Text 14. SYSTEM OF MATING
The principle of mating the animals is to evolve outstanding and improved types of animals which can render better service to man. The art of mating the animals implies the proper application of principles of heredity for the animal improvement. System of mating can be classified into inbreeding and outbreeding, depending on genetic relationship of the individuals or on phenotypic resemblance of the individuals in order to obtain better type of animals in the next generation.
Inbreeding is a mating system in which individuals mated are more closely related than the average of their breed or population concerned. It means the mating of males and females which are related. Animals seemed to be related only when they have one or more ancestors in common in the first 4 to 6 generations of their pedigree. The intensity of inbreeding depends upon the degree of relationship. Close inbreeding denotes mating of closely related individuals like Dam to Son or Sire to Daughter or Full Brother to Full Sister.
Effects of inbreeding: By this system of inbreeding, the percentage of gene pairs are increasingly made homozygous and the percentage of gene pairs are decreasingly made heterozygous in the population.
Inbreeding is utilized as a tool in livestock breeding to form distinct lines or families within a breed and also it is widely utilized to develop inbred lines that can be used for crossing purposes to exploit hybrid vigor. Yet another use of inbreeding is to uncover deleterious genes in animals used as sires. The usual practice is to mate the sire to 25 or 35 of its own daughter and if none of the resulting progenies exhibit recessive deleterious traits the sire is enrolled for use in the breeding programs.
Text 15. SHEEP
After cattle-rearing sheep-breeding ranks perhaps first among the various pursuits of pastoral farming. Sheep are ruminants and while they are fond of concentrated they must also have such feeds as grass and hay. They like leguminous plants too.
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The male sheep is known as the ram. The female sheep is called a ewe, and the little sheep are known as lambs.
Sheep are mainly bred for their meat (mutton) and for the wool they yield. There are accordingly two main type of sheep-breeding: for wool and for mutton. There is also a medium breed: the wool-mutton breed. But after all sheep are of course most valued for their wool. The annual clip (that is the quantity of wool sheared) of wool is a major factor in the economy of many countries. The best sheep are fine-fleece. Every effort is made in the USSR to bread new and better strains: fine-fleece, semi-fine fleece and long staple. This is carried out mainly by cross-breeding. Sheep also yield milk out of which a special kind of cheese is made and mutton which contains a high percent of fats and proteins. Flocks graze not only on well established pasturages, but also even on semi-desert or dry grazing land.
What is remarkable about the next branch of animal husbandry – hog-breeding – is that it quickly yields returns. The production cycle of hogs (or swine) is much shorter than that of cattle or sheep. Another significant feature of hog- breedings is (just as dairy farming) that it gives a vast range of food stuffs derived from pork. Among them are: bacon, lard, ham, sausage, tinned (canned) pork. At the same time hog skins are sent to tanneries while hog-bristles find a vast sphere of application, down to the manufacture of toothbrushes. Even the offals of swine are used, for instance, in sausage-making.
Hogs are omnivorous. However, unlike other domestic animals the pig has a small stomach and requires its food in concentrated form. Pigs grow more rapidly than any other class of farm animals in relation to their weight. The daily ration of a pig should be composed of feeds with a definite proportion of carbohydrates, proteins, vitamins and minerals.
The male pig is called a hog and the female pig a sow, the small piglets are often called just pigs. The fattening of pigs should, within reasonable limits, be begun from an early stage. As soon as the litter of newly farrowed pigs is weaned (from the sow), they should be properly fed on a balanced ration.
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