Fish parasitology in Kashmir: Effect of fish parasites on the fish population, their pathogenecity and control

1998 ◽  
Vol 47 ◽  
pp. 170
Author(s):  
M.Z. Chishti
2017 ◽  
Vol 21 (2) ◽  
pp. 75
Author(s):  
Abreha Tesfaye ◽  
Awot Teklu ◽  
Tilaye Bekelle ◽  
Tsegay Tkue ◽  
Etsay Kebede ◽  
...  

2021 ◽  
Vol 21 (1) ◽  
pp. 1-10
Author(s):  
Putri Aji Sutarni ◽  
Elisa Herawati ◽  
Agung Budiharjo

Parasitic disease in aquaculture brings a great challenge to fish production. Appropriate control measure and treatment can be carried out if farmers are equipped with sufficient information on the existence of infection and its consequences on fish health. This study aimed to examine the prevalence of endoparasites in the intestine of Nile tilapia (Oreochrois niloticus) and any histological changes associated with the infection. Forty fishes were collected using purposive sampling technique at two location of aquaculture ponds in Janti village from September to December 2019. Each sampling size consisted of 10% of the total fish population in the pond. Identification of parasites was performed based on their morphology according to the standard method. Three genera of nematodes were found from fishes cultured at aquaculture ponds from local farmers, but not from that of PBIAT (Hatchery and Freshwater Fish Aquaculture). The endoparasites were identified as Cichlidogyrus sp., Acanthocephalus sp., and Ceratomyxa sp. with prevalence of 25% and intensity of 1.2%. Histological sections of the intestine of fish infected with these parasites showed alteration in the mucosa layers, such as edema and extension of the mucosa. Information on the presence of endoparasites and its effect on nile tilapia culture is important for fish farmers because it can be used as reference to control fish parasites effectively.


2014 ◽  
Vol 2014 ◽  
pp. 1-11 ◽  
Author(s):  
Yi Zhang ◽  
Qiaoling Zhang ◽  
Jinghao Li ◽  
Qingling Zhang

The objective of this paper is to study systematically the bifurcation and control of a single-species fish population logistic model with the invasion of alien species based on the theory of singular system and bifurcation. It regardsSpartina anglicaas an invasive species, which invades the fisheries and aquaculture. Firstly, the stabilities of equilibria in this model are discussed. Moreover, the sufficient conditions for existence of the trans-critical bifurcation and the singularity induced bifurcation are obtained. Secondly, the state feedback controller is designed to eliminate the unexpected singularity induced bifurcation by combining harvested effort with the purification capacity. It obviously inhibits the switch of population and makes the system stable. Finally, the numerical simulation is proposed to show the practical significance of the bifurcation and control from the biological point of view.


2020 ◽  
Author(s):  
Andrew W. Szopa-Comley ◽  
Callum Duffield ◽  
Indar W. Ramnarine ◽  
Christos C. Ioannou

AbstractConsistent inter-individual differences in behaviour (i.e. animal personality variation) can influence a range of ecological and evolutionary processes, including predation. Variation between individual predators in commonly measured personality traits, such as boldness and activity, has previously been linked to encounter rates with their prey. Given the strong selection on predators to respond to prey, individual predators may also vary consistently in their response to prey in a manner that is specific to the context of predation. By studying wild piscivorous fish (pike cichlids, Crenicichla frenata) in their natural environment using experimental presentations of prey and control stimuli, we show that individual predators differ consistently in the amount of time spent near prey. Crucially, these differences were not explained by the behaviour of the same individuals in control presentations (the same apparatus lacking prey), suggesting that variation in the response to prey reflects a ‘predator personality trait’ which is independent from other individual traits (body size, boldness and/or neophobia) and environmental factors. Pike cichlids which spent more time near prey also attacked prey at a higher rate. These findings imply that the risk posed by individual predators cannot always be adequately predicted from typically studied axes of personality variation.


2015 ◽  
Vol 2 (2) ◽  
Author(s):  
Nuzhat Shafi ◽  
Javed Ayub ◽  
Tasleem Akhtar

The physico-chemical parameters and the fish parasites of the River Neelum were studied at three sampling sites, i.e., Pattika, Tali Mandi, and Domail. Water temperature and rate of flow of water were significantly higher at Domail than Pattika and Tali Mandi. ANOVA showed that dissolved oxygen, total suspended solids, inorganic suspended solids, and organic matter of the bottom mud kept on fluctuating and showed a significant difference between three selected sites. Although, these variables showed variations, they remained within tolerable limits set by WHO. Three species of potentially harmful parasites, i.e., Dactylogyrus vastator, Procamallanus laevionchus, and Argulus foliaceus were isolated from fish population of the River Neelum, however, these parasites do not pose any severe threats to general fish life


2021 ◽  
Vol 79 (4) ◽  
pp. 187-204
Author(s):  
Matija Pofuk

Abstract Non-indigenous parasite fauna of freshwater fish has not been studied extensively in Croatia, despite the long history of introductions and translocations of alien fish species into inland waters. Negative implications for aquaculture production and wild native fish species have been frequently associated with the introduction of non-native parasite species. Hence, the present paper attempts to lay out a historical overview of the suspected localities, time frames and pathways of introduction for non-indigenous fish parasites into inland waters of Croatia, therefore producing a list of species. In total, 16 non-native fish parasites have been recorded in inland waters of Croatia, aquaculture establishments being identified as initial points of introduction. However, a paucity of information exists on the overall prevalence of infection as well as the economic impact on aquaculture production. In addition, limited information is available about the presence and potential ecological impact of non-indigenous parasites on endemic fish fauna in areas of high biodiversity, such as the water bodies of the Adriatic Sea Basin. Therefore, there is an urgent need and opportunity for multidisciplinary cooperation between different stakeholders, including government, scientists, in both biological and veterinary disciplines, and the industry, with the aim of extensive surveys to determine the potential impact on aquaculture production and wild fish population of high conservation value.


Author(s):  
R. R. Dils ◽  
P. S. Follansbee

Electric fields have been applied across oxides growing on a high temperature alloy and control of the oxidation of the material has been demonstrated. At present, three-fold increases in the oxidation rate have been measured in accelerating fields and the oxidation process has been completely stopped in a retarding field.The experiments have been conducted with an iron-base alloy, Pe 25Cr 5A1 0.1Y, although, in principle, any alloy capable of forming an adherent aluminum oxide layer during oxidation can be used. A specimen is polished and oxidized to produce a thin, uniform insulating layer on one surface. Three platinum electrodes are sputtered on the oxide surface and the specimen is reoxidized.


Author(s):  
D. M. DePace

The majority of blood vessels in the superior cervical ganglion possess a continuous endothelium with tight junctions. These same features have been associated with the blood brain barrier of the central nervous system and peripheral nerves. These vessels may perform a barrier function between the capillary circulation and the superior cervical ganglion. The permeability of the blood vessels in the superior cervical ganglion of the rat was tested by intravenous injection of horseradish peroxidase (HRP). Three experimental groups of four animals each were given intravenous HRP (Sigma Type II) in a dosage of.08 to.15 mg/gm body weight in.5 ml of.85% saline. The animals were sacrificed at five, ten or 15 minutes following administration of the tracer. Superior cervical ganglia were quickly removed and fixed by immersion in 2.5% glutaraldehyde in Sorenson's.1M phosphate buffer, pH 7.4. Three control animals received,5ml of saline without HRP. These were sacrificed on the same time schedule. Tissues from experimental and control animals were reacted for peroxidase activity and then processed for routine transmission electron microscopy.


Author(s):  
G. Mazzocchi ◽  
P. Rebuffat ◽  
C. Robba ◽  
P. Vassanelli ◽  
G. G. Nussdorfer

It is well known that the rat adrenal zona glomerulosa steroidogenic activity is controlled by the renin-angiotensin system. The ultrastructural changes in the rat zona glomerulosa cells induced by renovascular hypertension were described previously, but as far as we are aware no correlated biochemical and morphometric investigations were performed.Twenty adult male albino rats were divided into 2 experimental groups. One group was subjected to restriction of blood flow to the left kidney by the application of a silver clip about the left renal artery. The other group was sham-operated and served as a control. Renovascular hypertension developed in about 10 days: sistolic blood pressure averaged 165 ± 6. 4 mmHg, whereas it was about 110 ± 3. 8 mmHg in the control animals. The hypertensive and control rats were sacrificed 20 days after the operation. The blood was collected and plasma renin activity was determined by radioimmunological methods. The aldosterone concentration was radioimmunologically assayed both in the plasma and in the homogenate of the left capsular adrenal gland.


Author(s):  
Henry I. Smith ◽  
D.C. Flanders

Scanning electron beam lithography has been used for a number of years to write submicrometer linewidth patterns in radiation sensitive films (resist films) on substrates. On semi-infinite substrates, electron backscattering severely limits the exposure latitude and control of cross-sectional profile for patterns having fundamental spatial frequencies below about 4000 Å(l),Recently, STEM'S have been used to write patterns with linewidths below 100 Å. To avoid the detrimental effects of electron backscattering however, the substrates had to be carbon foils about 100 Å thick (2,3). X-ray lithography using the very soft radiation in the range 10 - 50 Å avoids the problem of backscattering and thus permits one to replicate on semi-infinite substrates patterns with linewidths of the order of 1000 Å and less, and in addition provides means for controlling cross-sectional profiles. X-radiation in the range 4-10 Å on the other hand is appropriate for replicating patterns in the linewidth range above about 3000 Å, and thus is most appropriate for microelectronic applications (4 - 6).


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