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.

See also

Westminster System

The Westminster System is a democratic system of government modelled after that of the United Kingdom system of government and used in Westminster, the seat of government, hence its name. It is used in a number of Commonwealth nations such as Canada, Australia, Malaysia, Singapore, Jamaica, New Zealand and India and in non-Commonwealth states like the Republic of Ireland. It is a series of procedures for operating a legislature. Although Westminster systems are parliamentary systems, there are parliamentary governments, such as Germany and Italy, whose legislative procedures differ considerably from the Westminster system.

Aspects of the Westminster system include:

Most of the procedures of a Westminster system, though not in the Republic of Ireland, are typically defined by convention, practice and precedent along with, or rather than, codification through a written constitution. Many older constitutions using the Westminster system may not even mention the existence of a head of government or Prime Minister, with the office's existence and role evolving outside the primary constitutional text.



In a Westminster system, the members of parliament are elected by popular vote. The head of government is usually chosen by being invited to form a government by the head of state or representative of the head of state (ie, governor-general in some Commonwealth states), not by parliamentary vote. (See Kiss Hands.)

There are notable exceptions to the above in the Republic of Ireland, where the President of Ireland has a mandate through direct election, and the Taoiseach (prime minister) prior to appointment by the President of Ireland is nominated by the democratically elected lower house, Dáil Éireann.

Because of the mandate and the potentially significant constitutional powers of the Irish president, some authorities believe the Irish constitution is as similar to semi-presidential systems, as it is to Westminster. Similarly, under the constitutions of some Commonwealth countries, a president or Governor-General may possess clear and significant reserve powers. One example is the Australian constitutional crisis of 1975. Because of constititional differences, the formal powers of presidents and Governors-General vary greatly from one country to another. However, as Governor-Generals are not directly elected, they lack the popular mandate held, for example, by an Irish president. Because of this, Governor-Generals rarely risk the public disapproval which would result from them making unilateral and/or controversial uses of their powers.

The head of government, usually called the Prime Minister, must be able either (a) to control a majority of seats within the lower house, (b) ensure the existence of no absolute majority against them. If the parliament passes a resolution of no confidence or if the government fails to pass a major bill such as the budget, then the government must either resign so that a different government can be appointed or seek a parliamentary dissolution so that new public elections may be held in order to re-confirm or deny their mandate.

Many political scientists have argued that the Australian system of government was consciously devised as a blend of Westminster and the United States system of government, especially since the Australian Senate is a very powerful upper house. Hence the nickname "Washminster system". One implication is that although the Australian Senate is fully-elected, it maintains similar powers to those held by the British House of Lords, prior to 1911, to block supply to a government with a majority in the lower house.

Although the dissolution of the legislature and the call for new elections is formally done by the head of state, by convention the head of state acts according to the wishes of the head of government.

In exceptional circumstances the head of state may either refuse a dissolution request, as in the King-Byng Affair, or dismiss the government, as in the Australian constitutional crisis of 1975. Either action is likely to bend or break existing conventions. The Lascelles Principles were an attempt to create a convention to cover similar situations, but have not been tested in practice.


The Westminster system has a very distinct appearance when functioning, with many British customs incorporated into day-to-day government function. A Westminster-style parliament is usually a long, rectangular room, with two rows of seats and desks on either side. The chairs are positioned so that the two rows are facing each other. The intended purpose of this arrangement is to create a visual representation of the conflict-filled nature of parliamentary government. Traditionally, the opposition parties will sit in one row of seats, and the government party will sit in the other. Of course, sometimes a majority government is so large, it must use the "opposition" seats as well. In the lower house at Westminster (the House of Commons) there are two lines on the floor in front of the government and opposition benches which members may only cross when exiting the chamber. The distance between the lines is the length of two swords.

At one end of the room sits a large chair, for the Speaker of the House. The speaker usually wears a black robe, and in many countries, a wig. Robed parliamentary clerks often sit at narrow tables between the two rows of seats, as well.

Other ceremonies sometimes associated with the Westminster system include an annual Speech from the Throne (or equivalent) in which the Head of State gives a special address (written by the government) to parliament about what kind of policies to expect in the coming year, and lengthy "opening of parliament" ceremonies that often involve the presentation of a large, ceremonial mace.


There are a number of consequences of the Westminster system. They tend to have extremely well-disciplined legislative parties in which it is highly unusual and generally suicidal for a legislator to vote against their party and in which no confidence votes are very rare. Also, Westminster systems tend to have strong cabinets in which cabinet members other than the prime minister are politicians with independent basis of support. Conversely, legislative committees in Westminster systems tend to be weak.

Another convention of the Westminster system was, in theory, ministers were responsible for the actions of their departments. Even though government departments can be huge bureaucracies with powerful senior staff, the ministers in charge of departments would be held accountable for mistakes of their organizations, even if they were not directly involved. Such a convention of ministerial responsibility, if it ever had been explicitly followed, is now ignored, with ministers now only forced to resign when they become such an embarrassment to their government that they are too much of a political liability to leave in their post.

A related convention is that members of the Cabinet are collectively seen as responsible for government policy and ministers must publicly support the policy of the government regardless of their private reservation. A minister is duty-bound to resign if they cannot publicly support the government's position.

Some countries under the Westminster system

See also