Effects of ration and Fasciola infection on some blood parameters of ewes.

This study was conducted using fourty cross-bred ewes in 5 groups of which one was kept as a control and the others were infected with metacercariae of Fasciola gigantica twice at the beginning of the experiment and 200 days from the first. The four infected groups fed on basal ration or high protein ration with or without mineral mixture. Blood samples were taken from the five groups to assess the concentrations of plasma fibrinogen and serum total proteins, albumin, globulin, calcium and inorganic phosphorous. Results indicated that ewes total serum protein, albumin and globulin were decreased by Fasciola infection. The decrease was only significant in ewes fed basal ration with or without mineral mixture. Mineral mixture had no effect on the later blood parameters of infected ewes although little improvement in blood serum globulin was noticed. Plasma fibrinogen decreased significantly by infection. The level of plasma fibrinogen was improved by feeding high protein ration but did not affect by adding mineral mixture to any of the ration used. Infection was also found to decrease blood serum inorganic phosphorous but not calcium level. Feeding high protein ration with or without mineral supplement maintained blood serum inorganic phosphorous as that of the uninfected ewes. Blood serum calcium to phosphorous ratio of ewes fed only basal ration was significantly higher than that of other groups.

An epidemiological assessment of Ambrosia maritima on the transmission of schistosomiasis in the Egyptian Nile Delta.

Ambrosia maritima (Damsissa), a proven molluscicide, was investigated in a seven year epidemiological trial in four villages in the northern Egyptian Nile Delta. Schistosoma mansoni prevalence and other measures of infection were initially high in the four villages before the trial began. Two villages were used to test the impact of A. maritima application both on snail populations and on infection in the village population. Two villages were held as controls and not treated with A. maritima. The entire population of all four villages was included in the study. Prevalence and other measures of infection fell dramatically following treatment with praziquantel 40 mg kg-1 body weight. On annual follow ups, the prevalence of infection and geometric mean egg counts began to increase back to original levels in both test and control villages; age adjusted incidence rates were lower in one test village, but higher in the other when compared to the control villages. Snail populations were destroyed in the treated canals and drains located near the test villages. The lack of a clear epidemiologic impact is discussed.

The molluscicidal properties of Ambrosia maritima L. (Compositae). 4. Temporal and spatial distribution of Biomphalaria alexandrina in Egyptian village irrigation systems with reference to schistosomiasis transmission control.

Data on the temporal and spatial distribution of Biomphalaria alexandrina were collected throughout one year in two village irrigation systems near Alexandria, Egypt. Snails bearing Schistosoma mansoni cercariae were found from May to December but about 80% of annual transmission potential was confined from June to August. Although snail infection rates were generally 0-2%, higher rates were recorded and tended to be associated with smaller number snail collections. Infected snails were found in most canal and drain types and were judged to be present across most of the irrigated area of each village. In view of the dispersed nature of both infected snails and human-water contact in the area, it is suggested that schistosomiasis transmission is more widespread than focal. Effective transmission control using molluscicides should therefore require application to all village irrigation water-courses. The difficulties these various findings might impose on the use of commercial molluscicides are discussed and some possible advantages of the alternative plant molluscicide, Ambrosia maritima are noted.

The molluscicidal properties of Ambrosia maritima L. (Compositae). 3. A comparative field trial using dry and freshly-harvested plant material.

A comparative trial of freshly-harvested and dry forms of the plant molluscicide, Ambrosia maritima is described. The plant was grown near Alexandria, Egypt and gave a weight ratio of 4:1 for fresh: dry, mature plants. Applications of plant material were made to irrigation watercourses at dosage levels of 560 mg . l-1 fresh and 70 and 140 mg . l-1 dry in May and 280 mg . l-1 fresh and 70 mg . l-1 dry in June. Snail numbers were reduced to low levels after two weeks in all treatments. Statistically significant differences could not be detected between the molluscicidal effects of fresh and dry material or their use in May and June. The cultivated plant has a similar order of activity to that collected from the wild. The snail number reduction was maintained to the end of the year in all treatments. This confirms an earlier finding that a correctly-timed, single application of the plant is capable of controlling snails throughout the entire schistosomiasis transmission season in Lower Egypt.

The molluscicidal properties of Ambrosia maritima L. (Compositae). 2. Results from a field trial using dry plant material.

A field trial in Egypt of the plant molluscicide, Ambrosia maritima is described. Applications of 140, 70 and 35 mg/l-1 dry, whole plant were made to irrigation canals and drains in June. The treatment effect took between 1 and 5 weeks to become fully established. The reduction in the numbers of alive Biomphalaria alexandrina snails was generally more than 90% and was virtually the same at all treatment levels and in both types of watercourse. The snail population remained at a low level for at least 3 months until September-October. The possible use of a single, annual application in April or May in controlling snails throughout the main schistosomiasis transmission season in Lower Egypt is suggested.

The molluscicidal properties of Ambrosia maritima L. (compositae). 1. Design for a molluscicide field trial.

The composite plant, Ambrosia maritima is toxic to the snail intermediate hosts of schistosomiasis. A field trial was required to confirm this activity. A preliminary survey of irrigation canals and drains was conducted using two snail sampling methods. The results have been used to indicate the minimum number of watercourses which would have to be treated and the number of sampling stations per watercourse required to establish statistical significance in a kill of snails obtained from a molluscicide treatment.