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31.
Rodrigo Otávio
De Almeida Ozório Carlos Andrade Viriato Manuel Freitas Andrade Timóteo Luís Eugénio Castanheira da Conceição Luisa Maria Pinheiro Valente 《Journal of the World Aquaculture Society》2009,40(1):95-103
Although reported as a slow growing species, to date information regarding nutritional dynamics of blackspot seabream, Pagellus bogaraveo, is limited, especially during ongrowing phase. This study determined the effects of different feeding levels on growth response, body composition, and energy expenditure of blackspot seabream juveniles (initial weight = 64 g). Fish were allocated in nine indoor tanks (15 fish per tank) and fed a basal diet twice daily at increasing levels (2.5, 3.3, and 4.1 g feed/kg0.8/d) for 138 d. Growth response decreased with decreasing feeding levels, but only at 2.5 g feed/kg0.8/d (P < 0.001). Differences in growth rates were positively correlated with body lipid content (r2 = 0.90). Net protein utilization decreased with each increase in feeding level. The energy requirement for zero growth (maintenance) and the estimated energy loss on starvation were calculated as 22.6 and 17.9 kJ/kg0.8/d, respectively. The energy cost for protein and lipid gain was calculated as 3.8 and 1.4 kJ/kJ energy deposited, respectively. This study suggested that blackspot seabream may grow slower than the other close‐related species because of its higher demand of dietary protein energy in favor of lipid deposition. 相似文献
32.
Carine de Freitas Souza Matheus Dellaméa Baldissera Adriane Erbice Bianchini Elisia Gomes da Silva Rosa Helena Veraz Mourão Lenise Vargas Flores da Silva Denise Schmidt Berta Maria Heinzmann Bernardo Baldisserotto 《Fish physiology and biochemistry》2018,44(1):21-34
The viability using Lippia alba essential oil as an anesthetic for fish was studied, particularly with respect to physiological effects during recovery. Anesthesia of silver catfish (Rhamdia quelen) using 100 and 300 μL L?1 of two different chemotypes of L. alba essential oil (citral EO-C and linalool EO-L) prevented the increase of plasma cortisol levels caused by handling, but did not avoid alterations in energetic metabolism. Silver catfish did not have increased the levels of thiobarbituric acid reactive species in the kidney and liver during recovery after anesthesia with either EO, avoiding lipid damage. On the other hand, fish anesthetized with EO-C showed higher protein carbonylation levels, superoxide dismutase, catalase, and glutathione S-transferase activities and non-protein thiol group levels in both tissues compared to controls. Our results suggest that both oils show antioxidant capacity, but anesthesia with EO-L does not cause damage to lipids or proteins, only temporary changes, typical of physiological adjustments during recovery from anesthesia. Therefore, EO-L is an effective anesthetic for silver catfish with fewer side effects than EO-C. 相似文献
33.
Janaína?Camacho?da?Silva Antonio?Sergio?Varela Junior J?sie?Shwartz?Caldas Clarissa?da?Silva Freitas Joziel?Gon?alves?Botelho Elton?Pinto?Colares Carine?Dahl?CorciniEmail authorView authors OrcID profile 《Fish physiology and biochemistry》2016,42(1):93-102
Sperm quality tests on fish are classically used for evaluating cryopreservation procedures, and they are also promising to assess aquatic toxicity and biomarkers of xenobiotic effects on reproduction. Osmotic shock from the storage medium is one of the main factors affecting sperm quality during evaluation. Thus, the objective of this study was to evaluate the effects of different osmolalities (240–460 mOsm/kg) for at least 4 days on the sperm quality parameters of the viviparous fish Jenynsia multidentata. The level of significance was (P < 0.05). The plasma osmolality of J. multidentata is 326 ± 3.9 mOsm/kg. The motility of fresh semen was higher in osmolalities of 280 and 300 mOsm/kg but did not differ between osmolalities from 240 to 320 mOsm/kg. Above 380 mOsm/kg, the motility observed was 0 %. Over the time period studied motility increased with increasing osmolality, and the most constant and long-lasting rates were between 300 and 320 mOsm/kg. On the 4th day of evaluation, higher membrane integrity rates were observed between 280 and 360 mOsm/kg, higher mitochondrial membrane potential was observed between 300 and 460 mOsm/kg, and higher DNA integrity rates were observed between 260 and 380 mOsm/kg. Moreover, osmolalities ≥460 and ≤240 resulted in the lowest motility and DNA integrity levels. Over 4 days, the plasma membrane integrity was significantly lower at ≤260 and ≥400 mOsm/kg, and the mitochondrial membrane potential was significantly lower only in osmolalities ≤240 mOsm/kg. Therefore, we conclude that for sperm quality preservation in J. multidentata, an osmolality of 300–320 mOsm/kg of the most suitable diluent is necessary. Furthermore, we conclude that the storage of sperm in a hyposmotic (<260 mOsm/kg) or hyperosmotic (>400 mOsm/kg) solution affects not only motility but also other sperm quality parameters. 相似文献
34.
35.
Oliveiro Caetano de Freitas Neto Sonia Luisa Silva Lages Adriano Oliveira Torres Carrasco Angelo Berchieri Junior 《Tropical animal health and production》2009,41(8):1607-1614
We analyzed ostriches from an equipped farm located in the Brazilian southeast region for the presence of Salmonella spp. This bacterium was investigated in 80 samples of ostrich droppings, 90 eggs, 30 samples of feed and 30 samples of droppings
from rodents. Additionally, at slaughter-house this bacterium was investigated in droppings, caecal content, spleen, liver
and carcasses from 90 slaughtered ostriches from the studied farm. Also, blood serum of those animals were harvested and submitted
to serum plate agglutination using commercial Salmonella Pullorum antigen. No Salmonella spp. was detected in any eggs, caecal content, liver, spleen, carcass and droppings from ostriches and rodents. However,
Salmonella Javiana and Salmonella enterica subsp. enterica 4, 12: i:- were isolated from some samples of feed. The serologic test was negative for all samples. Good sanitary farming
management and the application of HACCP principles and GMP during the slaughtering process could explain the absence of Salmonella spp. in the tested samples. 相似文献
36.
Blood transfusion is an important routine practice in veterinary medicine that generally involves the use of whole blood. Permanent blood donors must be vaccinated against viral infections that affect dogs and submitted periodically to clinical and serological examinations to detect blood-transmitted diseases. There is a very high risk of transmission of infectious agents, particularly protozoans due to their long incubation periods, subclinical persistence in infected animals and likelihood of remaining viable in bloodstocks. The aim of the present study was to identify the potential of asymptomatic and oligosymptomatic dogs for Leishmania infantum transmission as a result of transfusional practice. Nineteen Leishmania-seropositive adult dogs of both sexes and indeterminate breeds were selected as donors. The animals were classified as symptomatic, oligosymptomatic or asymptomatic after clinical examination and evaluated by ELISA, IFAT and bone marrow puncture biopsies. Whole blood and monocyte cells were collected and used for dog's serological evaluation and inoculation in culture medium as well as in hamsters. All but three dogs were positive for IFAT, ELISA and parasite demonstration in bone marrow aspirates, irrespective of their clinical conditions. Parasites were detected in 77% of the whole blood and 90% of the monocyte cultures. Six months after inoculation with whole blood or monocytes, hamsters developed infection and clinical symptoms of visceral leishmaniasis, as well as positive titres measured by ELISA. These results suggest that blood donors should be monitored periodically and rigorously for Leishmania infection, to prevent dissemination of the disease through blood transfusion. 相似文献
37.
38.
Irene Rodrigues Freitas William Renzo Cortez-Vega Carlos Prentice 《Journal Of Aquatic Food Product Technology》2013,22(7):1034-1044
ABSTRACTThis work aimed to evaluate the physicochemical and functional properties of proteins recovered from whitemouth croaker (Micropogonias furnieri) and Argentine anchovy (Engraulis anchoita) residues obtained by the process of acid solubilization using HCl at pH = 2 and alkaline solubilization using NaOH at pH = 12 and isoelectric precipitation (pH = 5.5). The proximate composition and functional properties were determined. The solubilization and water holding capacity (WHC) of the recovered protein were studied in the pH range of 3, 5, 7, 9, and 11. The high protein content and lowest lipid reduction presented by the protein recovered from the whitemouth croaker residue and obtained by the acid solubilizing process was 97.1 and 98.4%, respectively. The maximum solubilized protein was at pH 3 and 11, and the minimum solubilized protein was at pH 5 for both species. The greater ability to retain oil was observed for the alkaline solubilization process (8.3 and 7.3). The lower WHC was at pH 5. The acid and alkali residue concentrates of the whitemouth croaker presented higher WHC at pH 3 and 11. These proteins can be used in preparing edible films and have been used to produce bioactive compounds for supplements or functional ingredients. 相似文献
39.
Camilla A Santos Bruno C Rossini Carla G Marques Pedro M Galetti Jr Patrícia D Freitas 《Aquaculture Research》2012,43(10):1567-1570
In the present work, EST‐SSR (expressed sequence tag‐simple sequence repeat) loci were obtained by screening 45 000 ESTs from the Pacific white shrimp Litopenaeus vannamei, which was available in a database of the ShEST (Shrimp EST Genome Project) consortium. Fifty‐two of 600 EST‐SSR loci were selected. From this total, 21 EST‐SSRs were polymorphic among 40 individuals and had their gene products ascribed. Two to 20 alleles per locus were detected and the observed heterozygosity ranged from 0.15 to 0.86. Eight loci presented a significant heterozygote deficit after the Bonferroni correction, which was attributed to null alleles. Seven loci were able to have their protein products, molecular functions and biological processes determined. Our results are promising for future studies that relate the levels of these gene polymorphisms with different biological responses to stress in aquaculture. 相似文献
40.
I. R. A. Sant'Anna C. R. C. Doria C. E. C. Freitas 《Fisheries Management and Ecology》2014,21(4):322-329
The middle stretch of the Madeira River has supported an intensive commercial fishery for several decades. Developed in an area of rapids and waterfalls, this fishery focuses primarily on catfish stocks, mainly pimelodids. Data from fish landings collected in the years immediately prior to the start in operations of two large hydroelectric dams were used to estimate growth and mortality rates for Pirinampus pirinampu (Spix & Agassiz) and Brachyplatystoma platynemum Boulenger. In addition, stock assessment was carried out for both species, and the results used to evaluate the status of the fishery. Mean population parameters were L∞ = 80.85 cm (total length), k = 0.52 year?1, ? = 3.53, A0.95 = 6 year, M = 0.87, F = 1.41–1.64 and Z = 2.28–2.51 for P. pirinampu; and L∞ = 95.55 cm (total length), k = 0.28 year?1, ? = 3.40, winter point = 0.41, A0.95 = 11 year, M = 0.55, F = 0.16–0.35 and Z = 0.71–0.90 for B. platynemum. Yield‐per‐recruit analysis indicated P. pirinampu was overfished and that the stock of B. platynemum was under‐exploited. Moreover, overfishing of the P. pirinampu stock and the effects of fragmentation caused by the construction of the dam should be monitored. 相似文献