Olsen, Eggs are released in water and hatch after developing into a miracidia. The non-feeding miracidia often swim through water searching for a suitable snail host, either until they reach the host or die.
When sensing the soft outer layer of a snail, they attach and burrow into the tissue. The miracidia transform to mature sporocysts in about 11 days, and release rediae. Rediae mature with in 10 days with cercariae. For mature cercariae to emerge from their intermediate hosts at an optimal time during the day , they have two eyespots capable of sensing light. After emergence, they encyst on plants to reach their next host, a ruminant. Excystment of metacercariae occurs when they sense the changed physicochemical conditions such as temperature, substance concentration, and pH inside the ruminant host, and adult flukes utilize topological features in the intestines of ruminants in order to guide their migration.
The time from infection to egg release after the adult's mature is about 60 to days. Olsen, ; Sukhdeo and Sukhdeo, The mating systems are not complex, as adult Paramphistomum cervi are monoecious having both male and female organs , and self-fertilize.
Adult rumen flukes are monoecious, fertilizing their own eggs and keeping them inside the uterus. Egg release is synchronized with the emergence from hibernation of their intermediate snail hosts.
The flukes reach sexual maturity in the rumens of ruminants and release eggs in the intestine and which are expelled along with feces. The time from egg hatching to a mature adult releasing eggs is about 95 days. A complete cycle of this species from egg to release of the next generation of eggs lasts from to days, provided at each stage the parasite is able to find its next host. However, the lifespan of an adult is unknown. Flukes release their eggs and time their maturation to coincide with the availability of their intermediate snail hosts.
Timing also coincides with the favorable environmental factors such as temperature and precipitation. However, it is unknown how environmental factors specifically induce or delay egg-laying and fluke maturation and how this mechanism is accomplished. Mature cercariae sense light with their two eyespots and emerge from their intermediate snail hosts during the daytime. Metacercariae excystment occurs when a change in physicochemical conditions is sensed, which allows them to excyst at the correct time inside the ruminant host.
Adult flukes use topological features to guide their migration inside the rumen of the definite host. Gupta, et al. Mature cercariae have two eyespots capable of sensing light, as they need to emerge in the day to find a snail host. The specific mechanisms of these behaviors are currently not well understood. Members of the species do not communicate amongst each other. Sukhdeo and Sukhdeo, Adults attach to the villi in the rumens of definitive ruminant hosts and sap nutrients from the intestine, although they can wander into the bile and pancreatic ducts, as do other trematodes.
Sporocysts, rediae, and cercariae feed on the tissues and bodily fluids of the intermediate snail host. No specific predators are known for Paramphistomum cervi. Adult livestock rumen flukes are the main parasites that occur in the rumen of cattle, sheep, goats, and buffaloes. However, mild infection is not seriously damaging to hosts. Large numbers of young flukes migrating throughout the intestine can cause acute parasitic gastroenteritis, likely leading to high morbidity and mortality.
When paramphistomosis is diagnosed early in an animal, treatment can prevent the animal from suffering permanent damage to its rumen and bile ducts. Younger animals are more likely to succumb to paramphitomosis.
There are no known positive effects of Paramphistomum cervi on humans. Paramphistomum cervi causes severe economic losses to milk production since the flukes sap nutrients from their hosts, causing weight loss and a decrease in milk production.
The parasite has become so prevalent that cattle mortality due to paramphistomosis has reached 80 to 90 percent in India, the Republic of South Africa, and Australia. Each blotted nitrocellulose membrane and Henderson, Zymed Laboratory Inc. Materials and methods room temperature for 3—5 min until the bands appeared. Finally, the reaction was stopped by adding distilled water. Collection of adult parasites and antigen preparation 2.
Statistical analysis Adult P. They All data from immunoblotting were calculated for the were washed several times with 0. Protein concentration was deter- ven P. Collection of serum samples infection samples that show negative result. Forty paramphistomosis sera were obtained from cattle 3. Negative control sera were collected from 35 kDa.
The major bands appeared at 66, 52, 45, 26, 15 normal cattle whose stool samples at the time of blood col- and Sera of individual cattle with P. These pooled as well as individual sera were Fig. The reactivities against antigenic com- used in immunoblotting analysis. The band at 52 kDa arrow is detected by sera from all infected animals. Molecular weight markers are shown in lane marked STD. One dis- infected cattle, normal controls, and from cattle infected tinct immunogenic band at 52 kDa was found to react with with other closely related parasites Fasciola gigantica all of the sera from infected cattle with clinically diagnosed and strongylids.
However, there were reactivities of P. The positive and negative predictive values were immunogenic Paramphistomosisa Fasciolosisb Strongylidsc Normal Immunoblots of adult Paramphistomum cervi whole worm antigens from total number of sera tested percent of positive sera.
Molecular weight marker is shown in STD lane. Moreover, the results of an immunoblotting cases Positive Negative study showed a strong reactivity of all infected sheep sera Positive 40 1 41c against somatic antigens at 20—23 kDa and excretory— Negative 0 49 49d secretory ES antigens at 23—27 kDa.
Likewise, Gorman et al. Furthermore, it was 4. Discussion reported that the ES antigens of F. Only the 25 eggs. Another observation by Kim stage of infection when eggs have not been produced. It was believed that immunodiagno- of 8 kDa. Thus, this antigen was suggested for use in the sis would be a better method, but no such method had been diagnosis of human fasciolosis. In addition, Yokananth et al.
They suggested that the 34 and 28 kDa parasites. For example, Cervi et al. Maleewong et al. Similarly, Yadav and Gupta reported that the immunoblotting analysis of F. Another study of F. They suggested that a the somatic extract of adult F. Using the same approaches, our present study of P.
As well, this antigen did not react with sera weights ranging from 23 to kDa. The immunogenic from cattle infected with two closely related parasites, i. The diagnostic sensitivity and were similar to those in the present study.
Furthermore, they candidate antigen for the immunodiagnosis of cattle reported that antigens at 64—52 kDa might be possible can- paramphistomosis caused by P. Cleavage of structural proteins during the assembly of the head of bacteriophage T4. Nature , — Lowry, O. Protein This research was supported by Thailand Research measurement with the folin phenol reagent. Scholarship to Panat Anuracpreeda. Maleewong, W. We acknowledged the assistance of Dr.
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