scholarly journals Can the parasitic fauna on Nile tilapias be affected by different production systems?

2010 ◽  
Vol 82 (2) ◽  
pp. 493-500 ◽  
Author(s):  
Maurício L. Martins ◽  
Tatiana M.P. Azevedo ◽  
Luciana Ghiraldelli ◽  
Neuza Bernardi

This study compared the parasitic fauna on Nile tilapias kept with swine dejects and tilapia from fee fishing fed commercial ration. A total of 360 fish were analyzed from August 2003 to July 2004 in a facility situated in Nova Trento, Santa Catarina, Brazil. No significant difference was observed in both systems. The parasite fauna in both systems were slightly similar, with the presence of the following parasites: Trichodina magna and T compacta (Ciliophora); Cichlidogyrus sclerosus and Cichlidogyrus sp. (Monogenoidea); and Lamproglena sp. (Lernaeidae). Parasitological analyzes did not differ among fishes kept with swine dejects and in fee fishing with commercial diet (P >0.05). The total prevalence of trichodinids in the gills of fish kept with swine dejects was 1.7% as compared to the one kept in fee fishing with commercial diet (0.6%). The Monogenoidea prevalence and mean intensity in the gills and body of fish from fee fishing was 16.5% and 2.6, and compared to other system was 13.2% and 0.8, respectively. This study showed that low stocking density and low water temperature in that region were responsible for the maintenance of good health and lower parasitism rate.

2021 ◽  
Vol 24 ◽  
Author(s):  
Lorena Caroline da Silva ◽  
Daniella Martins Pimenta ◽  
Victor Augusto Forti ◽  
Fernando Cesar Sala ◽  
Simone Daniela Sartorio de Medeiros ◽  
...  

Abstract The consumption and cultivation of curly kale in Brazil is recent and information on production systems and their acceptance by the consumer are scarce. The aim of this work was to evaluate the sensory characteristics of curly kales cultivated using the conventional and hydroponic systems, considering the treatments: cultivation under the conventional system, without fertilization (A), conventional system with organic fertilizers (C, E) and hydroponic system (F). The harvests were performed at 60, 90 and 120 days after planting for the plants cultivated using the conventional system and at 30 days for the hydroponic system. The total chlorophyll index content and the sensory analyses of ranking of difference and acceptance were analyzed. The lowest chlorophyll index in the curly kales was verified for the one cultivated under the hydroponic system. In the ranking test, the darkest green color was obtained for the curly kale produced using the conventional system and for the attributes aroma, sweet and bitter taste and crunchiness, there was no significant difference.


2016 ◽  
Vol 85 (3) ◽  
pp. 223-226 ◽  
Author(s):  
Camilo Romero ◽  
Rafael Heredia ◽  
Saira Aguilar ◽  
Nadyeli Nava ◽  
Jocelyn Pineda

Toxocariasis is a parasitic zoonosis caused by the nematode Toxocara canis, and less frequently Toxocara cati, whose final hosts are the dog and cat, respectively. It is acquired by the ingestion of embryonated parasite eggs; the ingestion of meat from animals carrying cystic larvae plays a central role in this disease. The study was conducted in Ayapango, Mexico. Ninety-two sheep where used, of which 72 were females and 20 males. The total prevalence of anti-Toxocara antibodies was 15.21% (14/92), ranging from 17.24% in the one to six months age group to 14.28% in the group older sheep six months, with a higher percentage in females (19.44%) compared to males (5.0%), with a significant difference between positive males and females older than six months of age (Chi-square test = 4.22, P < 0.05). The prevalence of anti-Toxocara antibodies in sheep suggests that a high number of animals are infected with Toxocara spp. The consumption of meat from paratenic hosts, including sheep, is considered a means of transmission of toxocariasis to humans.


1979 ◽  
Author(s):  
R. Kotitschke ◽  
J. Scharrer

F.VIII R:Ag was determined by quantitative immunelectrophoresis (I.E.) with a prefabricated system. The prefabricated system consists of a monospecific f.VIII rabbit antiserum in agarose on a plastic plate for the one and two dimensional immunelectrophoresis. The lognormal distribution of the f.VIII R:Ag concentration in the normal population was confirmed (for n=70 the f.VIII R:Ag in % of normal is = 95.4 ± 31.9). Among the normal population there was no significant difference between blood donors (one blood donation in 8 weeks; for n=43 the f.VIII R:Ag in % of normal is = 95.9 ± 34.0) and non blood donors (n=27;f.VIII R:Ag = 94.6 ± 28.4 %). The f.VIII R:Ag concentration in acute hepatitis B ranged from normal to raised values (for n=10, a factor of 1.8 times of normal was found) and was normal again after health recovery (n=10, the factor was 1.0). in chronic hepatitis the f.VIII R:Ag concentration was raised in the majority of the cases (for n=10, the factor was 3.8). Out of 22 carrier sera 20 showed reduced, 2 elevated levels of the f.VIII R:Ag concentration. in 5 sera no f.VIII R:Ag could be demonstrated. The f.VIII R:Ag concentration was normal for n=10, reduced for n=20 and elevated for n=6 in non A-non B hepatitis (n=36). Contrary to results found in the literature no difference in the electrophoretic mobility of the f.VIII R:Ag was found between hepatitis patients sera and normal sera.


1966 ◽  
Vol 53 (4) ◽  
pp. 673-680 ◽  
Author(s):  
Torsten Deckert ◽  
Kai R. Jorgensen

ABSTRACT The purpose of this study was to investigate whether a difference could be demonstrated between crystalline insulin extracted from normal human pancreas, and crystalline insulin extracted from bovine and porcine pancreas. Using Hales & Randle's (1963) immunoassay no immunological differences could be demonstrated between human and pig insulin. On the other hand, a significant difference was found, between pig and ox insulin. An attempt was also made to determine whether an immunological difference could be demonstrated between crystalline pig insulin and crystalline human insulin from non diabetic subjects on the one hand and endogenous, circulating insulin from normal subjects, obese subjects and diabetic subjects on the other. No such difference was found. From these experiments it is concluded that endogenous insulin in normal, obese and diabetic human sera is immunologically identical with human, crystalline insulin from non diabetic subjects and crystalline pig insulin.


2014 ◽  
Vol 6 (1) ◽  
pp. 1032-1035 ◽  
Author(s):  
Ramzi Suleiman

The research on quasi-luminal neutrinos has sparked several experimental studies for testing the "speed of light limit" hypothesis. Until today, the overall evidence favors the "null" hypothesis, stating that there is no significant difference between the observed velocities of light and neutrinos. Despite numerous theoretical models proposed to explain the neutrinos behavior, no attempt has been undertaken to predict the experimentally produced results. This paper presents a simple novel extension of Newton's mechanics to the domain of relativistic velocities. For a typical neutrino-velocity experiment, the proposed model is utilized to derive a general expression for . Comparison of the model's prediction with results of six neutrino-velocity experiments, conducted by five collaborations, reveals that the model predicts all the reported results with striking accuracy. Because in the proposed model, the direction of the neutrino flight matters, the model's impressive success in accounting for all the tested data, indicates a complete collapse of the Lorentz symmetry principle in situation involving quasi-luminal particles, moving in two opposite directions. This conclusion is support by previous findings, showing that an identical Sagnac effect to the one documented for radial motion, occurs also in linear motion.


2021 ◽  
Vol 8 ◽  
pp. 238212052110294
Author(s):  
Sheila Harms ◽  
Anita Acai ◽  
Bryce JM Bogie ◽  
Meghan M McConnell ◽  
Ben McCutchen ◽  
...  

Introduction: Some studies on academic half days (AHDs) suggest that learning in this context is associated with a lack of educational engagement. This challenge may be amplified in distributed campus settings, where geographical disadvantages demand reliance on videoconferencing or considerable time spent travelling to in-person learning events. Concerns about the educational effectiveness of AHDs by learners within our distributed campus setting led to the development and evaluation of the One Room Schoolhouse (ORS), a unique, evidence-informed, community-based curriculum that partially replaced the AHD sessions delivered at the main campus. It was hypothesized that creating an AHD experience that was clinically reflective of the community in which residents practiced and where residents were given the autonomy to implement novel pedagogical elements would result in better test scores and improved learner satisfaction among ORS learners. Methods: The ORS was implemented at McMaster University’s Waterloo Regional Campus in 2017. Residents across training cohorts (N = 9) engaged in co-learning based on scenarios co-developed from clinical experiences within the region. The learning approach relied on multiple, evidence-informed pedagogical strategies. A multi-method approach was used to evaluate the ORS curriculum. Between-subject analyses of variance were used to compare scores on practice exams (COPE and PRITE), in-training assessment reports (ITARs), and objective structured clinical exams (OSCEs) between learners who took part in the ORS and learners at the main campus. A semi-structured focus group probing residents’ experiences with the ORS was analyzed using interpretive description. Results: ORS learners significantly outperformed learners at the main campus on the November OSCE ( p = .02), but not on the COPE, PRITE, ITARs, or September OSCE ( p’s < .05). Qualitative themes suggested advantages of the ORS in inspiring learning, engaging learners, and improving self-confidence in knowledge acquisition. These findings are aligned with the broader literature on learner agency, social development, and communities of practice. Conclusion: While the quantitative data only showed a significant difference between the 2 curricula on 1 measure (ie, the November OSCE), the qualitative findings offered an opportunity for educators to reimagine what medical education might consist of beyond the confines of a “traditional” AHD. Creating opportunities to enhance personal agency when acquiring knowledge, inspiring engagement about patient-related problems, and incorporating interdisciplinary learning through community engagement were critical pedagogical elements that were attributed to the success of the ORS.


2015 ◽  
Vol 2015 ◽  
pp. 1-5 ◽  
Author(s):  
Babacar Faye ◽  
Mouhamed Sarr ◽  
Khaly Bane ◽  
Adjaratou Wakha Aidara ◽  
Seydina Ousmane Niang ◽  
...  

This study evaluated the one-year clinical performance of a one-step, self-etch adhesive (Optibond All-in-One, Kerr, CA, USA) combined with a composite (Herculite XRV Ultra, Kerr Hawe, CA, USA) to restore NCCLs with or without prior acid etching. Restorations performed by the same practitioner were evaluated at baseline and after 3, 6, and 12 months using modified USPHS criteria. At 6 months, the recall rate was 100%. The retention rate was 84.2% for restorations with prior acid etching, but statistically significant differences were observed between baseline and 6 months. Without acid etching, the retention rate was 77%, and no statistically significant difference was noted between 3 and 6 months. Marginal integrity (93.7% with and 87.7% without acid etching) and discoloration (95.3% with and 92.9% without acid etching) were scored as Alpha or Bravo, with better results after acid etching. After one year, the recall rate was 58.06%. Loss of pulp vitality, postoperative sensitivity, or secondary caries were not observed. After one year retention rate was of 90.6% and 76.9% with and without acid conditioning. Optibond All-in-One performs at a satisfactory clinical performance level for restoration of NCCLs after 12 months especially after acid etching.


Micromachines ◽  
2020 ◽  
Vol 12 (1) ◽  
pp. 3
Author(s):  
Kyo-in Koo ◽  
Andreas Lenshof ◽  
Le Thi Huong ◽  
Thomas Laurell

In the field of engineered organ and drug development, three-dimensional network-structured tissue has been a long-sought goal. This paper presents a direct hydrogel extrusion process exposed to an ultrasound standing wave that aligns fibroblast cells to form a network structure. The frequency-shifted (2 MHz to 4 MHz) ultrasound actuation of a 400-micrometer square-shaped glass capillary that was continuously perfused by fibroblast cells suspended in sodium alginate generated a hydrogel string, with the fibroblasts aligned in single or quadruple streams. In the transition from the one-cell stream to the four-cell streams, the aligned fibroblast cells were continuously interconnected in the form of a branch and a junction. The ultrasound-exposed fibroblast cells displayed over 95% viability up to day 10 in culture medium without any significant difference from the unexposed fibroblast cells. This acoustofluidic method will be further applied to create a vascularized network by replacing fibroblast cells with human umbilical vein endothelial cells.


2011 ◽  
Vol 142 ◽  
pp. 233-237
Author(s):  
Han Wen Yuan ◽  
Fang Chen ◽  
Qiao Qing Xu ◽  
Shi Yuan Gong ◽  
Zhang Jie Chu ◽  
...  

The effects of stocking density on various growth parameters and sex reversal in the rice field eel (Monopterus albus) were investigated by evaluating steroid hormone, the gonadosomatic index (GSI) and sex ratio. Fish (mean initial weight of 9.88 ± 0.70 g) were stocked to densities of 4, 20, 36, 52, 68, 84 or 100 fish/m2 in cages (2 m × 1 m × 1.5 m) in a pond, with five replicate cages for each density. Fish were fed for 420 days on a formulated isocaloric diet containing 40.22% crude protein and 12.86 MJ/kg. Serum E2 and T concentrations were determined by radioimmunoassays. There were no significant differences in final bodyweight (FBW) and daily weight gain (DWG) for fish in the groups containing less than 52 fish/m2, while FBW and DWG were significant lower in groups at 68 fish/m2 or more. Specific growth rate (SGR) differed significantly between the 84 and 100 fish/m2 groups compared with the 4, 20 and 36 fish/m2 groups. There was no significant difference in SGR in groups containing less than 84 fish/m2. There were no significant difference between the 4 and 20 fish/m2 groups in net yield (NY), but these groups did differ significantly from the other groups. The final condition factors of fish stocked at 84 or 100 fish/m2 were significantly lower than fish stocked at the other densities. E2 and T hormone concentrations declined as stocking density increased, while GSI values increased initially but then reduced with increasing stocking density. Female ratio and survival decreased with increasing stocking density. The proportion of male fish was significantly greater in the three highest stocking density groups. Therefore, high stocking density may promote sex change from female to male in M. albus.


2021 ◽  
Vol 63 (1) ◽  
Author(s):  
Per-Arne Åhlen ◽  
Göran Sjöberg ◽  
Margareta Stéen

Abstract Background The parasitic fauna of beavers (Castor fiber and C. canadensis) has been well studied in many parts of their respective areas of distribution. In Scandinavia there have, however, been limited investigations conducted on the parasites of beavers in recent times. The present study is the first quantitative survey of parasites on beavers living in Sweden and elsewhere in Scandinavia. We investigated the parasitic fauna of the Eurasian beaver (C. fiber) in a North–South gradient in Sweden. The aim of the study was to investigate parasite distribution and prevalence in particular, related to average yearly air temperature and different age groups of beavers. A total of 30 beavers were sampled at eight localities, spanning a 720 km North–South gradient during the springs of 1997 and 1998. Results Five parasite taxa were identified. Four of these were present in all of the examined beavers, Stichorchis subtriquetrus (trematode), Travassosius rufus (nematode), Platypsyllus castoris (coleopteran), and Schizocarpus spp. (arachnid). A higher number of new infections of S. subtriquetrus, and more adults of T. rufus, were seen in beavers in southern Sweden where temperatures are higher. One-year old beavers had a higher infestation of S. subtriquetrus, but not of T. rufus, than older individuals. Conclusions The parasite fauna of Swedish beavers mirrored the impoverished parasite fauna of the original Norwegian population, and the high prevalence of parasites could be due to low major histocompatibility complex (MHC) polymorphism. Young beavers had a higher load of trematodes, probably depending on behavioural and ecological factors. Warmer temperatures in southern localities likely contributed to increased endoparasite loads.


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