Melophagus ovinus
Encyclopedia
Melophagus ovinus, or the sheep ked, is a brown, hairy fly
that resembles a tick
. This wingless fly is about 4 to 6 mm long and has a small head, is a fly
from the family
Hippoboscidae
. They are blood-feeding parasite
s of sheep. The legs of the sheep ked are very strong and are tipped with claws. Sheep ked lives their whole lives in the wool of sheep. Sheep ked are most commonly found on the neck, shoulders and underbelly of the host animal.
including Iceland
, and the Faroe Islands
, as well as North West Africa
, Mongolia
, and North India
. Introduced and established in Kenya
, South Africa
, Japan
, Australia
, New Zealand
, most of North America
, and many parts of South America
including Tristan da Cunha
and the Falkland Islands
.
(Ovis ammon), Bighorn Sheep
(Ovis canadensis) and Dall Sheep
(Ovis dalli).
e.
The female fly will produce a single larva
at a time, retaining the larva internally until it is ready to pupa
te. The larva feeds on the secretions of a milk gland in the uterus
of the female. After three larval instar
s, a white pre-pupa which immediately forms a hard dark puparium. This is deposited on the wool of the sheep and are attached with a glue-like material. The larva immediately hardens and becomes a darker color forming a puparium, which will contain the pupa. This pupal stage lasts for 19 to 23 days in the summer and 20 to 36 days in the winter. Pupal stages are not susceptible to insecticides. If removed form the host, the adult live for 7–10 days.
in sheep, though there is little evidence that they are bluetongue disease vectors in nature. In lambs the sheep ked may cause anemia and reduce weight gain. The sheep ked feeds on the blood of its host and therefore causes irritation to the sheep, leading it to rub, producing both loss and damage of the wool. It also makes firm, hard nodules that develops on the skin called a cockle, this will reduce the value of the hide. The ked feces also stains the sheep's wool reducing its value. They also transmit Trypanosoma melophagium nonpathogenic protozoan parasite of sheep.
Melophagus ovinus himalayae Maa, 1969 is from Nepal
and Tibet
. Its host is the yak
(Bos grunniens), and domestic cattle
.
Fly
True flies are insects of the order Diptera . They possess a pair of wings on the mesothorax and a pair of halteres, derived from the hind wings, on the metathorax...
that resembles a tick
Tick
Ticks are small arachnids in the order Ixodida, along with mites, constitute the subclass Acarina. Ticks are ectoparasites , living by hematophagy on the blood of mammals, birds, and sometimes reptiles and amphibians...
. This wingless fly is about 4 to 6 mm long and has a small head, is a fly
Fly
True flies are insects of the order Diptera . They possess a pair of wings on the mesothorax and a pair of halteres, derived from the hind wings, on the metathorax...
from the family
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
Hippoboscidae
Hippoboscidae
Hippoboscidae, the louse flies or keds are obligate parasites of mammals and birds. In this family there are winged species which can fly at least reasonably well, as well as others with vestigial or no wings which are flightless and highly apomorphic...
. They are blood-feeding parasite
Parasitism
Parasitism is a type of symbiotic relationship between organisms of different species where one organism, the parasite, benefits at the expense of the other, the host. Traditionally parasite referred to organisms with lifestages that needed more than one host . These are now called macroparasites...
s of sheep. The legs of the sheep ked are very strong and are tipped with claws. Sheep ked lives their whole lives in the wool of sheep. Sheep ked are most commonly found on the neck, shoulders and underbelly of the host animal.
Distribution
Native to most of EuropeEurope
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...
including Iceland
Iceland
Iceland , described as the Republic of Iceland, is a Nordic and European island country in the North Atlantic Ocean, on the Mid-Atlantic Ridge. Iceland also refers to the main island of the country, which contains almost all the population and almost all the land area. The country has a population...
, and the Faroe Islands
Faroe Islands
The Faroe Islands are an island group situated between the Norwegian Sea and the North Atlantic Ocean, approximately halfway between Scotland and Iceland. The Faroe Islands are a self-governing territory within the Kingdom of Denmark, along with Denmark proper and Greenland...
, as well as North West Africa
Africa
Africa is the world's second largest and second most populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area...
, Mongolia
Mongolia
Mongolia is a landlocked country in East and Central Asia. It is bordered by Russia to the north and China to the south, east and west. Although Mongolia does not share a border with Kazakhstan, its western-most point is only from Kazakhstan's eastern tip. Ulan Bator, the capital and largest...
, and North India
India
India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...
. Introduced and established in Kenya
Kenya
Kenya , officially known as the Republic of Kenya, is a country in East Africa that lies on the equator, with the Indian Ocean to its south-east...
, South Africa
South Africa
The Republic of South Africa is a country in southern Africa. Located at the southern tip of Africa, it is divided into nine provinces, with of coastline on the Atlantic and Indian oceans...
, Japan
Japan
Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...
, Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
, New Zealand
New Zealand
New Zealand is an island country in the south-western Pacific Ocean comprising two main landmasses and numerous smaller islands. The country is situated some east of Australia across the Tasman Sea, and roughly south of the Pacific island nations of New Caledonia, Fiji, and Tonga...
, most of North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...
, and many parts of South America
South America
South America is a continent situated in the Western Hemisphere, mostly in the Southern Hemisphere, with a relatively small portion in the Northern Hemisphere. The continent is also considered a subcontinent of the Americas. It is bordered on the west by the Pacific Ocean and on the north and east...
including Tristan da Cunha
Tristan da Cunha
Tristan da Cunha is a remote volcanic group of islands in the south Atlantic Ocean and the main island of that group. It is the most remote inhabited archipelago in the world, lying from the nearest land, South Africa, and from South America...
and the Falkland Islands
Falkland Islands
The Falkland Islands are an archipelago in the South Atlantic Ocean, located about from the coast of mainland South America. The archipelago consists of East Falkland, West Falkland and 776 lesser islands. The capital, Stanley, is on East Falkland...
.
Hosts
The primary host of M. ovinus is the domestic sheep. There are also doubtful records on ArgaliArgali
The argali, or the mountain sheep is a wild sheep, which roams the highlands of Central Asia . It is the biggest wild sheep, standing at the shoulder, measuring long and weighing , with a maximum known weight of...
(Ovis ammon), Bighorn Sheep
Bighorn Sheep
The bighorn sheep is a species of sheep in North America named for its large horns. These horns can weigh up to , while the sheep themselves weigh up to . Recent genetic testing indicates that there are three distinct subspecies of Ovis canadensis, one of which is endangered: Ovis canadensis sierrae...
(Ovis canadensis) and Dall Sheep
Dall Sheep
The Dall sheep , Ovis dalli, is a species of sheep native to northwestern North America, ranging from white to slate brown in color and having curved yellowish brown horns...
(Ovis dalli).
Life history
Sheep ked lives for typically four to six months, in this time they may produce from 10 to 20 larvaLarva
A larva is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle...
e.
The female fly will produce a single larva
Larva
A larva is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle...
at a time, retaining the larva internally until it is ready to pupa
Pupa
A pupa is the life stage of some insects undergoing transformation. The pupal stage is found only in holometabolous insects, those that undergo a complete metamorphosis, going through four life stages; embryo, larva, pupa and imago...
te. The larva feeds on the secretions of a milk gland in the uterus
Uterus
The uterus or womb is a major female hormone-responsive reproductive sex organ of most mammals including humans. One end, the cervix, opens into the vagina, while the other is connected to one or both fallopian tubes, depending on the species...
of the female. After three larval instar
Instar
An instar is a developmental stage of arthropods, such as insects, between each molt , until sexual maturity is reached. Arthropods must shed the exoskeleton in order to grow or assume a new form. Differences between instars can often be seen in altered body proportions, colors, patterns, or...
s, a white pre-pupa which immediately forms a hard dark puparium. This is deposited on the wool of the sheep and are attached with a glue-like material. The larva immediately hardens and becomes a darker color forming a puparium, which will contain the pupa. This pupal stage lasts for 19 to 23 days in the summer and 20 to 36 days in the winter. Pupal stages are not susceptible to insecticides. If removed form the host, the adult live for 7–10 days.
Disease vector
It has been indicated by experiments that the sheep ked is capable of transmitting bluetongue virusBluetongue disease
Bluetongue disease or catarrhal fever is a non-contagious, non-zoonotic, insect-borne, viral disease of ruminants, mainly sheep and less frequently cattle, goats, buffalo, deer, dromedaries and antelope...
in sheep, though there is little evidence that they are bluetongue disease vectors in nature. In lambs the sheep ked may cause anemia and reduce weight gain. The sheep ked feeds on the blood of its host and therefore causes irritation to the sheep, leading it to rub, producing both loss and damage of the wool. It also makes firm, hard nodules that develops on the skin called a cockle, this will reduce the value of the hide. The ked feces also stains the sheep's wool reducing its value. They also transmit Trypanosoma melophagium nonpathogenic protozoan parasite of sheep.
Subspecies
The subspeciesSubspecies
Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...
Melophagus ovinus himalayae Maa, 1969 is from Nepal
Nepal
Nepal , officially the Federal Democratic Republic of Nepal, is a landlocked sovereign state located in South Asia. It is located in the Himalayas and bordered to the north by the People's Republic of China, and to the south, east, and west by the Republic of India...
and Tibet
Tibet
Tibet is a plateau region in Asia, north-east of the Himalayas. It is the traditional homeland of the Tibetan people as well as some other ethnic groups such as Monpas, Qiang, and Lhobas, and is now also inhabited by considerable numbers of Han and Hui people...
. Its host is the yak
Yak
The yak, Bos grunniens or Bos mutus, is a long-haired bovine found throughout the Himalayan region of south Central Asia, the Tibetan Plateau and as far north as Mongolia and Russia. In addition to a large domestic population, there is a small, vulnerable wild yak population...
(Bos grunniens), and domestic cattle
Cattle
Cattle are the most common type of large domesticated ungulates. They are a prominent modern member of the subfamily Bovinae, are the most widespread species of the genus Bos, and are most commonly classified collectively as Bos primigenius...
.