Publication Date:
2021-05-19
Description:
In order to do this study, 150 Persian sturgeon having 75g mean weight transferred to tanks with 500L volume.
After dividing the fishes into two groups (experimental and control group), the fingerlings fed by concentrate
food that contained different levels of Zataria multiflora essential oil (15g/kg, 25g/kg, 50g/kg, 100g/kg) for 8
weeks. Finally, sampling carried out on blood and serum of fishes. After preparing the samples based on
standard methods, haematology and serology studies, performed. The results showed significant difference in
mean and standard deviation of monocytes between experimental and control groups (P〈0.05). In treatment
25g/kg, monocyte count was more than other treatments. But there are no significant differences in mean and
standard deviation of other white blood cells. The results of serologic studies showed no significant differences
in serum indices (C3, C4 and total protein) (P〈0.05), but there is significant difference in mean and standard
deviation of albumin. So that , the mean and standard deviation in treatments 15g/kg and 25g/kg and control
group were more than treatments 50g/kg and 100g/kg of Zataria multiflora essential oil.
Also , this is the first record of the anesthetic effect of Zataria multiflora essence on fish. In this research the
effect of 50 and 100 ppm concentrations of Zataria multiflora essence on the rainbow trout (Oncorhynchus
mykiss) fry with average weight of 15±2 grams and Salmo trutta caspius with average weight of 40±4 grams has
been studied. In this research the water temperature was 16-17 ºC, dissolved oxygen 7±0.2 and pH═8. The
average time of coming to unconscious in 50 ppm and 100 ppm concentration in both Oncorhyncus mykiss and
Salmo trutta caspius was 3 and 2 minutes respectively; and the means of balance and return of anesthesia were 2
and 3 minutes respectively, and the average time of inducing balance and recovering consciousness was 2 and 3
minutes respectively. Moreover, in contrast there is a significant difference between the time of inducing
unconsciousness and recovery in all kinds of fish (p 〈 0.0001).
The fish anesthetized with 100 ppm concentration after transference to water without Zataria multiflora essence
were calm for 30 minutes and showed no reaction to weak stimuli (such as touching). In regard of the time of
falling into unconsciousness and the time of recovery by different degrees of concentration of Zataria multiflora
essence there is no significant difference between Oncorhyncus mykiss and Salmo trutta caspius (p 〉 0.05). This
research also shows that Zataria multiflora essence has an anesthetic effect but because of its unwanted severe
irreparable breathing (respiration) side effects and also the deformation of the fish which is against the fisheries’
ethics (death accompanied with extreme pain) it would be better not to be used as anesthetics.
One of the advantages of Zataria multiflora essence as anesthetics is its low concentration (25 ppm) for
anesthetizing the fish and also its economical cost. In addition, this essence has antimicrobial and disinfecting
effects and, therefore, it can remove the infection from the external surface of the body of the fish.
One of the most noticeable defects of Zataria multiflora essence is that at the time of anesthetizing it causes a
state of excitement and irritability in the fish which manifests itself in the speed of swimming and the possibility
of jumping out of water. As a result, although Zataria multiflora essence has anesthetizing effects, it is
recommended not to be used for anaesthetizing the fish, because it posses unwanted side effects that may even
cause the death of the fish; however, it may be used as a sedative during manipulating the fish.
Description:
Iranian Fisheries Science Research Institute
Description:
Published
Keywords:
Zataria multiflora
;
Essential oils
;
Persian Sturgeon
;
Trout
;
Zataria multiflora
Repository Name:
AquaDocs
Type:
Report
,
Refereed
Format:
222pp.
Permalink
