الفهرس 
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Abstract
Fusariomycosis in cultured shrimp Leptomonus Vannami with trials of its control
The primary goal of the find out about used to be to pick out the pathogen related with the fungal contamination in the Litopenaeus vannamei system. This was once executed the usage of traditional morphology. Another purpose of this learn about was once to consider the pathogenicity of the recognized stress of F. solani on Litopenaeus vannamei by means of experimental contamination and to decide if it ought to be accountable for the determined symptoms. Using fungal increase manage agents, the outcomes of 4 antifungal sellers (formic acid, butyric acid, imperative oils of Origanium vulgaris and copper sulfate) on F. solani have been tested.
Shrimps and experimental protocol :
group A was represented as infected positive control where the shrimp infected with F. solani (1/10 dose of 5.0×106 conidial suspension /ml equal to 5.0×105 conidial suspension /ml) .
group B was dived into three sub groups and fed on three types of ration one containing 1 gram of formic acid /kg ration ; second was supplemented with 1ml of Butyric acid /kg ration and the third supplemented with 1 ml essential oils of O. vulgaris /kg ration while the last one was feed on the normal ration but treated with 2ppm of copper sulphate and in the same time fish infected with 5.0×105conidial suspension /ml F. solani.
group C used to be served as poor control. Feed consumption for twenty-eight days used to be recorded, and feces used to be eliminated daily. Each therapy crew used to be fed with one of the 4 diets 4 instances every day to satiation for 28 days. Salinity all through the test was once maintained at 25 ppt, dissolved oxygen above four ppm, and water temperature at 29±1°C. Leftover feed and feces had been siphoned daily, and 10 p.c of the water used to be exchanged each and every three days.
Our results indicated that :
1) Prevalence of Black-gill diseases in infected Litopenaeus vannamei (L. vannamei)
In gross sign, white and brown to black colour gill was observed. The percentage of gill affected broodstocks have gradually increased from February 2020 to June 2020 and then enhanced hastily to reach a peak of 2% during the month of March 2020 in a male shrimp. Whereas, the percentage of gill affected female broodstocks have gradually increased from January 2020 to June 2020 and enhanced hastily to reach a peak of 13.04% during the month of February and March 2020. The highest prevalence of 29.03 and 26.087% was observed in both the sex (male and female) during the month of June 2020.
2) Clinical signs of naturally infected broodstock L. vannamei
The naturally infected broodstock shrimp L. vannamei showed black gill disease as; black gill melaninization leaflet; gills showed brown discoloration. The gross symptoms of localized contamination in the cuticle or sub-cuticle are known as shell disorder or black or brown spot ailment and these superficial infections. The floor of the worried cuticle used to be regularly irregular and sometimes lacked the epicuticle (erosion).
3) Fusarium tabacenum Lactophenol
stained spore suspension by way of mild microscopic observation. Microconidia have been discovered as very abundant, comparatively short, non-septate, elliptical and straight structures. Macroconidia had been least abundant, elongated, cylindrical, barely curved, fusiformed and three septate buildings .
4) Fusarium oxysporum
Comparatively short, non-septate, few numbers of macroconidia bearing conidiophores and attribute ‘foot cell’ used to be seen at the base of the Fusarium species macroconidia. Aerial conidiophores branched loosely, irregularly or verticillately, bearing conidiogenous cells on the apices, proliferating sympodial.
5) Fusarium solani
Mycelium of F. solani was dense and hyaline. Hyphae were highly septate, and an apical growth was also observed. Macroconidia ranged from 8-10 μm in length and were looking like sickle like curved shape. Microconidia were septate by a 1-2 septa revealed by light and scanning electron microscope.
6) Histopathological examination
Histological section of experimentally infected of L. vannamei with 5.0×105 conidial suspension /ml of F. solani showed that there are fungal hyphae had completely penetrated the gill tissues and gill leaflets had a great infestation with fungal hyphae that destruct the raised cuticle and a cell