Oophorectomy

Oophorectomy is the surgical removal of the ovaries of a female animal. In the case of non-human animals, this is also called spaying. It is a form of sterilization.

The removal of the ovaries together with the Fallopian tubes is called salpingo-oophorectomy. Oophorectomy and salpingo-oophorectomy are not common forms of birth control in humans; more usual is tubal ligation, in which the Fallopian tubes are blocked but the ovaries remain intact.

In humans, oophorectomy is most usually performed together with a hysterectomy - the removal of the uterus. Its use in a hysterectomy when there are no other health problems is somewhat controversial.

In animals, spaying involves an invasive removal of the ovaries, but rarely has major complications; the superstition that it causes weight gain is not based on fact. Spaying is especially important for certain animals that require the ovum to be released at a certain interval (called estrus or "heat"), such as cats and dogs. If the cell is not released during these animal's heat, it can cause severe medical problems that can be averted by spaying or partnering the animal with a male.

Oophorectomy is sometimes referred to as castration, but that term is most often used to mean the removal of a male animal's testicles.

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Straits of Malacca

The Straits of Malacca is a narrow stretch of water between Peninsular Malaysia (West Malaysia) and the Indonesian island of Sumatra.

From an economic and strategic perspective the Straits of Malacca is one of the most important shipping lanes in the world, an equivalent of the Suez Canal, or the Panama Canal. The Straits form the main ship passageway between the Indian Ocean and the Pacific Ocean, linking three of the world's most populous nations: India, Indonesia and China. The Straits carry 50,000 vessels per year, carrying between one-fifth and one quarter of the world's sea trade. Half of all oil shipments carried by sea come through the Straits, in 2003, an estimated 11 million barrels a day, a trade that is expected to expand as oil consumption rises in China. As the Straits are only one-and-a-half nautical miles wide at their narrowest point, Phillips Channel in the Singapore Strait, they form one of the world's significant traffic bottlenecks (see link).

All these factors have caused the area to become a target for piracy and a perceived target for terrorism. Piracy has been a considerable problem in the Strait in recent years, rising from around 25 attacks in 1994 to a record 220 in 2000. Just over 150 attacks were carried out in 2003. This accounted for around one-third of all piracy in 2003.

The number of attacks rose again in the first half of 2004, and are the total number is expected to top the 2000 record. In response to the rising crisis, the Malaysian, Indonesian and Singaporean navies stepped up their patrols of the area in July 2004.

Fears of terrorism rest on the possibility that a large ship could be pirated and sunk at a shallow point in the Strait (it is just 25m deep at one point), effectively blocking the Strait. If successfully achieved, the attack would have a devastating effect on world trade. Opinions amongst security specialists differ about the feasibility and likelihood of the attacks.

Thailand has developed several plans that if implemented would diminish the economic significance of the Straits. The Thai government initially proposed to cut a canal through the Isthmus of Kra, shaving around 600 miles from the journey from Africa and the Middle East to the Pacific. A second alternative is to build a pipeline across the isthmus to carry oil to boats waiting on the other side. Proponents of the plan say it would cut the cost of delivery of a barrel of oil to Asia by about 50c.

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Last updated: 02-02-2005 09:40:10