Dictyocaulus viviparous is a parasite that affects cattle and deer. The lifecycle does not have an intermediate host. Adult male and female worms reside in the bronchial tree of the lung. Eggs are coughed up and swallowed and hatch as they pass through the intestinal tract. Larval worms on the pasture undergo two molts to reach the infectious L3 stage, which retains its L1 and L2 cuticle as a protective sheath. L3 are ingested by grazing cattle, and parasites molt twice before reaching the lung. Further growth and development are required to become mature, reproductive adults. In the feces, L1 mature to L2 and then to L3 which is the infective stage larvae. The L3 infective stage remains in the feces or the pasture and so when cattle come grazing they ingest the L3. L3 then go through intestinal system and penetrates the intestinal wall. They use the lymphatic system to reach the mesenteric lymph node where they mature to L4 then use d blood supply and lymphatic system to reach the lungs. Transmission Mode …show more content…
EHD can be contracted only in cases where the animal is bitten by a fly. So as to finish the life cycle of the virus, the female midge sucks the blood of an ungulate in order to take in protein from the blood. In North America, the main path for EHD is C. variipennis. Nevertheless, several species of mosquitoes and midges are able to spread virus. The virus can last for almost two months in an infected deer as it takes between five to ten days for the disease to
[1, 4, 5, 9, 13] There have been no documented cases where a human has contracted the disease from another human. [4] It appears, based on field and lab data, that infection requires direct contact with the virus through means such as contact with infective bodily secretions, urine, or tissues. [12] It is unknown to scientists how the virus can be maintained in the bat populations and avoids extinction as the host species becomes immune to its presence. [14] The incubation period from time of infection to the onset of symptoms is about 5-14 days in experimentally induced animals [4] and 8-14 days in natural field cases.
White-tailed deer, along with the rest of the Cervidae family, are facing a possible epidemic. Although the disease has not spread over the entire range CWD is efficiently transmitted between individuals. CWD is to the best of our knowledge 100% fetal and incubation can take a few years allowing for many possible transmissions. There also at this time is no form of vaccine or treatment for infected cervids. Despite efforts being put forth to control CWD, being a free-range family of animals proves control to be extremely difficult.
The biting midge (Culicoides imicola), which is responsible for this disease’s transmission, is usually contained within Mediterranean Europe; where the conditions have been exactly what the midge demands to survive (Society for General Microbiology NP). However, with an increase in average temperature of six degrees, the midge has been allowed to travel northward threatening the cattle throughout the area and even as far as England (Society for General Microbiology NP). The spread of the midge’s territory has led to an increased number of their population, along with the amount of infected cattle.
The most common way this disease is transmitted from one animal to the next is through mosquitoes. A mosquito carrying infective heartworm larvae bites a dog and transmits the infection to them. The larvae grow, develop, and migrate in the body over a period of 6 to 7 months, in which time they become sexually mature male and female worms. this is the prepatent period. The worms then reside in the heart, lungs, and associated blood vessels. The worms begin to mate and release microfilaria into the blood stream. When a mosquito bites an infected dog it takes in some of the microfilaria in the blood. After 10 to 30 days there is larvae in the mosquito’s salivary gland which can then be passed on to the next dog the mosquito bites.
Disease and parasitism play a pervasive role in all life. Many of these diseases start with microparasites, which are characterized by their ability to reproduce directly within an individual host. They are also characterized by their small size, short duration of infection, and the production of an immune response in infected and recovered individuals. Microparasites which damage hosts in the course of their association are recognized as pathogens. The level of the interaction and the extent of the resultant damage depends on both the virulence of the pathogen, as well as the host defenses. If the pathogen can overcome the host defenses, the host will be damaged and may not survive. If on the other hand the host defenses overcome the pathogen, the microparasite may fail to establish itself within the host and die.
The Web. 18 Jan. 2014. Levy, Sharon. A Plague of Deer. BioScience 56.9 (2006): 714–21.
Flatworms belong to the phylum Platyhelminthes. They have the simplest body plan of all bilaterally symmetrical animals. They are called flatworms because their bodies are compressed. The mouth is the only opening into the digestive cavity the flatworms have. Food is taken in through this hole and wastes are discharged also through this hole. Flatworms have a well-defined nervous, muscular, excretory, and reproductive system. The flatworm distributes the food it digests through a digestive tube that branches throughout all of its body parts. The fact that the worm’s body is flat serves many purposes. It allows the worm to hid in small spaces, to fit into the opening of other animals if the worm is parasitic, and it means that all the cells are close enough to the surface for exchange of oxygen and carbon dioxide with the environment (Meinkoth 399).
This parasite is spread through the bite of sandflies. There are three different types of infections and they each show varying degrees of severity. The cutaneous form produces mild skin ulcers, mucocutaneous produces ulcers in the mouth and nose, and the visceral form of the disease starts with skin ulcers and then fever, low red blood cell count, and an enlarged spleen and liver. The parasite is detected by a microscope and visceral can also be found by doing blood tests. 12 million people are in infected in 98 different countries and 2 million new cases are found every year. The disease also kills around 20 to 50 thousand people a year.
You wouldn’t think the carrier of this disease would come from a little mosquito bite but it does.
A disease is transmitted in one way or the other. Lyme disease is transmitted through a vector. The vector of the disease is an infected deer tick. The deer tick has to bite a person to spread the disease. When a deer tick bites a person (sucks blood), the Borrelia burgdoferi bacteria is transmitted into the persons body.
When researching diseases that affect animals, I chose to research one that deals with cattle. This disease would be a reproductive venereal disease called vibriosis. Vibriosis can affect all breeds of cattle, male or female, and is the most important cause of infertility in female cattle along with occasional abortions. This disease is caused by bacteria that live in the crevices of a bull’s prepuce, of a bull aged four years or older (Hansen, 1914). Age is a factor because the foreskin of a bull does not develop until then. The disease is spread from an infected bull to a cow during breeding. A bull might be clean, but then infected by a cow who was infected by a bull before him. Many bulls can go years without showing any signs of this disease, whereas female cattle may lose a calf to an abortion the next coming calving season.
Emerging Infectious Diseases (EIDS) are a disease of infectious origin whose incidence in humans has increased within the recent past threatens to increase in the near future. Over 30 new infectious agents have been detected worldwide in the last three decades; 60% of these are of zoonotic origin, and more than 2-3rds of these have originated in the wildlife (Dikid et al., 2013).
Wear gloves and proper cloths if handling the infected animals to prevent the direct contact.
one in which the host animal can live for a long enough time for the parasite to
In order for you to understand how Echinococcus works. You have to understand how it is transmitted into your system and begins infecting you. Echinococcus goes through several different steps on how it is developed and then transmitted to other hosts. The adult echinococcus tapeworm is about 5 mm long and lives in the small intestines of dogs and another canine species such as coyotes, wolves and foxes. The stage where a cyst begins usually occurs in intermediate hosts; typically sheep’s but they can also affect cattle’s, horses, camels, pigs and goats and many others. Tapeworm eggs are passed by the feces of infected dogs and then are digested by grazing sheep’s. These eggs then hatch into the embryos within the intestines, and then penetrate the intestines to be carried by the blood to major organs such as the liver and lungs. This larval stage of the parasite is called an oncosphere. The larval stage spreads by the bloodstream to target organs and other parts of the body, such as liver, lungs, ...