Journal name |
Veterinary Parasitology |
Publication year |
2012 |
Auther |
Mohamed A.A. Abd El-Galil a, Shawky M. Aboelhadid |
The present work was designed to study the prevalence of trichodinosis and gyrodactylosis
in Oreochromis niloticus fries, and to test the therapeutic efficacy and preventive efficacy
of garlic oil and crushed garlic cloves. Trichodinosis and gyrodactylosis are ectoparasitic
diseases that affect most warm freshwater fish, especially fries and fingerlings. In a private
O. niloticus fish hatchery, the prevalence of trichodinosis in 5-, 15- and 30-day-old-fries
was 37%, 23% and 40.5%, respectively. The highest infection intensity was detected in
30-day-old-fries. The gyrodactylosis was reported only in combination with trichodinosis.
In addition, we found that its prevalence in 5-, 15- and 30-day-old-fries was 17%, 19.5% and
29%, respectively. Mortality rate of fry in the first month of life was 53% as a result of injury
to these two types of parasites. The garlic oil and crushed garlic cloves were tested in both in
vitro and earthen ponds of the hatchery. Using 2-, 2.5- and 3-ppt (parts per thousand) garlic
oil for 4 h in vitro water bath treatment resulted in 100% recovery, while 1 and 1.5 ppt garlic
oil, respectively, needed 24 and 16 h to treat the infected fries. The treatment by 3 ppt garlic
oil as a water bath for 1 h treated the two diseases in 55% in 7 days from application in the
hatchery earthen pond. In the mean time, 300 mg L−1 crushed garlic cloves as an indefinite
bath in the hatchery earthen pond eliminated 68% of the diseases. The same protocol for
preventing the two diseases resulted in obtaining 65% and 75% of parasite free fries, for
garlic oil and crushed garlic cloves, respectively, compared to 53% of the control fries.
Crown Copyright © 2011 Published by Elsevier B.V. All rights reserved