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Porcine Zona Pellucida
Porcine zona pellucida (PZP) is the zona pellucida extracted from the ovaries of pigs which is used as a source of antigens for immunocontraception. The zona pellucida is a thick membrane that surrounds the unfertilised eggs of mammals. In order for an egg to be fertilised, sperm must first bind to, and then penetrate the zona pellucida. When porcine (pig) zona pellucida is injected into other mammals, antibodies are produced which attach to that animal's zona pellucida, preventing the sperm from attaching to the egg, therefore preventing fertilisation. Porcine zona pellucida has been used in wildlife contraception since the late 1980s. Animals with which PZP has been employed in this context include elephants, wild and/or feral horses, elk and whitetailed deer. It can be administered to captured animals via a standard syringe or administered to free ranging wildlife with a dart gun A dart gun is an air rifle that fires a dart. The dart is tipped with a hypodermic needle and fi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zona Pellucida
The zona pellucida (plural zonae pellucidae, also egg coat or pellucid zone) is a specialized extracellular matrix that surrounds the plasma membrane of mammalian oocytes. It is a vital constitutive part of the oocyte. The zona pellucida first appears in unilaminar primary oocytes. It is secreted by both the oocyte and the ovarian follicles. The zona pellucida is surrounded by the corona radiata. The corona is composed of cells that care for the egg when it is emitted from the ovary. This structure binds spermatozoa, and is required to initiate the acrosome reaction. In the mouse (the best characterised mammalian system), the zona glycoprotein, ZP3, is responsible for sperm binding, adhering to proteins on the sperm plasma membrane. ZP3 is then involved in the induction of the acrosome reaction, whereby a spermatozoon releases the contents of the acrosomal vesicle. The exact characterisation of what occurs in other species has become more complicated as further zona proteins h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Antigen
In immunology, an antigen (Ag) is a molecule or molecular structure or any foreign particulate matter or a pollen grain that can bind to a specific antibody or T-cell receptor. The presence of antigens in the body may trigger an immune response. The term ''antigen'' originally referred to a substance that is an antibody generator. Antigens can be proteins, peptides (amino acid chains), polysaccharides (chains of monosaccharides/simple sugars), lipids, or nucleic acids. Antigens are recognized by antigen receptors, including antibodies and T-cell receptors. Diverse antigen receptors are made by cells of the immune system so that each cell has a specificity for a single antigen. Upon exposure to an antigen, only the lymphocytes that recognize that antigen are activated and expanded, a process known as clonal selection. In most cases, an antibody can only react to and bind one specific antigen; in some instances, however, antibodies may cross-react and bind more than one antigen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Immunocontraception
Immunocontraception is the use of an animal's immune system to prevent it from fertilizing offspring. Contraceptives of this type are not currently approved for human use. Typically immunocontraception involves the administration of a vaccine that induces an adaptive immune response which causes an animal to become temporarily infertile. Contraceptive vaccines have been used in numerous settings for the control of wildlife populations. However, experts in the field believe that major innovations are required before immunocontraception can become a practical form of contraception for human beings. Thus far immunocontraception has focused on mammals exclusively. There are several targets in mammalian sexual reproduction for immune inhibition. They can be organized into three categories. ;Gamete production: Organisms that undergo sexual reproduction must first produce gametes, cells which have half the typical number of chromosomes of the species. Often immunity that prevents game ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wildlife Contraceptive
Wildlife contraceptives are contraceptives used to regulate the fertility of wild animals. They are used to control population growth of certain wild animals. Usage White-tailed deer may be controlled with contraceptives in suburban areas, where they are sometimes a nuisance. In parts of the United States, does are shot with darts containing a contraceptive vaccine, rendering them temporarily infertile.Schuerman, MBirth Control for Deer?.''Audubon'' February 8, 2002. The Humane Society of the United States runs a deer birth control program, but it is experimental; it may not be cost-effective in the long run. It may cost $300 to $1000 per deer. One contraceptive vaccine used is porcine zona pellucida (PZP), or derivatives. This form of immunocontraception prevents sperm from accessing an ovum. Another form of deer contraception, called GonaCon, produces antibodies to sex drive hormones in the deer, causing them to lose interest in mating. Similar forms of injectable contra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elephant
Elephants are the largest existing land animals. Three living species are currently recognised: the African bush elephant, the African forest elephant, and the Asian elephant. They are the only surviving members of the family Elephantidae and the order Proboscidea. The order was formerly much more diverse during the Pleistocene, but most species became extinct during the Late Pleistocene epoch. Distinctive features of elephants include a long proboscis called a trunk, tusks, large ear flaps, pillar-like legs, and tough but sensitive skin. The trunk is used for breathing, bringing food and water to the mouth, and grasping objects. Tusks, which are derived from the incisor teeth, serve both as weapons and as tools for moving objects and digging. The large ear flaps assist in maintaining a constant body temperature as well as in communication. African elephants have larger ears and concave backs, whereas Asian elephants have smaller ears, and convex or level backs. Elepha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mustang (horse)
The mustang is a free-roaming horse of the Western United States, descended from horses brought to the Americas by the Spanish. Mustangs are often referred to as wild horses, but because they are descended from once-domesticated animals, they are actually feral horses. The original mustangs were Colonial Spanish horses, but many other breeds and types of horses contributed to the modern mustang, now resulting in varying phenotypes. Some free-roaming horses are relatively unchanged from the original Spanish stock, most strongly represented in the most isolated populations. In 1971, the United States Congress recognized that "wild free-roaming horses and burros are living symbols of the historic and pioneer spirit of the West, which continue to contribute to the diversity of life forms within the Nation and enrich the lives of the American people". The free-roaming horse population is managed and protected by the U.S. Bureau of Land Management (BLM). Controversy surrounds the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Red Deer
The red deer (''Cervus elaphus'') is one of the largest deer species. A male red deer is called a stag or hart, and a female is called a hind. The red deer inhabits most of Europe, the Caucasus Mountains region, Anatolia, Iran, and parts of western Asia. It also inhabits the Atlas Mountains of Northern Africa; its early ancestors are thought to have crossed over to Morocco, then to Algeria, Libya and Tunisia via the Strait of Gibraltar, becoming the only species of true deer (Cervidae) to inhabit Africa. Red deer have been introduced to other areas, including Australia, New Zealand, the United States, Canada, Peru, Uruguay, Chile and Argentina. In many parts of the world, the meat ( venison) from red deer is used as a food source. Red deer are ruminants, characterized by a four-chambered stomach. Genetic evidence indicates that the red deer, as traditionally defined, is a species group, rather than a single species, though exactly how many species the group includes remains ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Deer
Deer or true deer are hoofed ruminant mammals forming the family Cervidae. The two main groups of deer are the Cervinae, including the muntjac, the elk (wapiti), the red deer, and the fallow deer; and the Capreolinae, including the reindeer (caribou), white-tailed deer, the roe deer, and the moose. Male deer of all species (except the water deer), as well as female reindeer, grow and shed new antlers each year. In this they differ from permanently horned antelope, which are part of a different family ( Bovidae) within the same order of even-toed ungulates (Artiodactyla). The musk deer (Moschidae) of Asia and chevrotains ( Tragulidae) of tropical African and Asian forests are separate families that are also in the ruminant clade Ruminantia; they are not especially closely related to Cervidae. Deer appear in art from Paleolithic cave paintings onwards, and they have played a role in mythology, religion, and literature throughout history, as well as in herald ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tranquillizer Gun
A dart gun is an air rifle that fires a dart. The dart is tipped with a hypodermic needle and filled with a tranquilizer, vaccine, or antibiotic. A dart gun containing a tranquillizer is called a tranquillizer gun ( also spelled tranquilizer, tranquilliser or tranquiliser). History The modern dart gun was invented in the 1950s by New Zealander Colin Murdoch. While working with colleagues to study populations of deer and wild goats introduced to New Zealand, he considered that the animals would be easier to catch, examine, and release if a dose of tranquillizer could be administered by projection from afar. To that end, Murdoch went on to develop a range of rifles, darts, and pistols. The first modern remote drug-delivery system was invented by scientists at the University of Georgia in the 1950s, and was the direct predecessor to the Cap-Chur equipment used worldwide for decades. In the early 1960s, a team in Kenya headed by Drs. Tony Pooley and Toni Harthoorn discovered that v ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mammal Female Reproductive System
Most mammals are viviparous, giving birth to live young. However, the five species of monotreme, the platypuses and the echidnas, lay eggs. The monotremes have a sex determination system different from that of most other mammals. In particular, the sex chromosomes of a platypus are more like those of a chicken than those of a therian mammal. The mammary glands of mammals are specialized to produce milk, a liquid used by newborns as their primary source of nutrition. The monotremes branched early from other mammals and do not have the teats seen in most mammals, but they do have mammary glands. The young lick the milk from a mammary patch on the mother's belly. Viviparous mammals are in the subclass Theria; those living today are in the Marsupialia and Placentalia infraclasses. A marsupial has a short gestation period, typically shorter than its estrous cycle, and gives birth to an underdeveloped (altricial) newborn that then undergoes further development; in many species, this t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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