Total and available tryptophan requirement of Nile tilapia,Oreochromis niloticus,fingerlings          下载免费PDF全文

M. Zaminhan  M. Michelato  V.R.B. Furuya  W.R. Boscolo  F.E. Araújo  T.P. Cruz  A.V. Urbich  W.M. Furuya 《Aquaculture Nutrition》2018,24(5):1553-1562

The dietary total and available requirement of tryptophan of Nile tilapia fingerlings was determined using linear regression analysis. Six hundred fish (3.4 ± 0.0 g) were fed diets containing 296.4 g/kg of crude protein and 14.1 MJ/kg of digestible energy. Five extruded diets containing 2.5, 3.0, 3.4, 3.8 and 4.2 g/kg of total tryptophan were evaluated. Fish were fed four times a day during 45 days. Final body weight, weight gain, feed intake, feed conversion ratio and net protein utilization of fish fed Trp 3.4 and Trp 3.8 diets were improved compared to fish fed Trp 2.5 and Trp 4.2 diets. No significant differences in survival rate, whole‐body moisture and ash were observed. Whole‐body amino acid profile of fish fed different diets did not differ statistically (p > .05). Fish fed Trp 3.0 and Trp 3.4 diets showed higher tryptophan retention compared to fish fed Trp 2.5 and Trp 4.2 diets. Excepting blood glucose, no effects of dietary tryptophan on haematological parameters were observed. The dietary total tryptophan requirement of Nile tilapia fingerlings based on weight gain was estimated to be 3.4 g/kg (11.0 g/kg of dietary crude protein) or 3.0 g/kg of available tryptophan (11.0 g/kg of dietary digestible protein).  相似文献   

Quality assessment of newly hatched mud crab,Scylla serrata,larvae          下载免费PDF全文

Emilia T Quinitio  Joana Joy dela Cruz‐Huervana  Fe D Parado‐Estepa 《Aquaculture Research》2018,49(1):75-80

Starvation and exposure to formalin were investigated as possible stress tests for evaluating the quality of mud crab, Scylla serrata, larvae. For the starvation stress test, newly hatched zoeae stocked in 150‐ml containers were either starved or fed rotifers. Similarly, newly hatched zoeae were stocked in containers with seawater of 0 (control), 20, 30 and 40 mg/L formalin for the formalin stress test. The zoeae from the same batches were used for seed production to monitor their performance and validate the results of stress tests. Starvation was found to be unsuitable for larval quality evaluation. However, the impact of initial food deprivation on the newly hatched larvae indicates that feeding immediately after hatching is necessary for mud crab larvae. Exposure of larvae to 40 mg/L formalin for 3 hr appeared to be a reliable and practical method for larval quality assessment as the survival of larvae in the mass production tanks validated the classification of good and poor quality batches in the stress tests. On this basis, a hatchery operator can decide which batch should be cultured further. Finally, there appears to be a link between the quality of larvae and the performance at the megalopa and early juvenile crabs.  相似文献   

Changes in Bacterial Populations During Bioremediation of Soil Contaminated with Petroleum Hydrocarbons     

Sergio Cisneros de la Cueva  César Hernández Rodríguez  Nicolás Oscar Soto Cruz  Juan Antonio Rojas Contreras  Javier López Miranda 《Water, air, and soil pollution》2016,227(3):91

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Antiparasitic efficacy of dietary administration of trichlorfon (Masoten®) in the control of Neoechinorhynchus buttnerae (Neochinorhynchidae) in Colossoma macropomum (Serrasalmidae)     

Castro  Liliane Araújo  Andrade-Porto  Sanny Maria  Oliveira  Rebeca Guimarães  Batista  Yasmin Luzeiro  Silva  Felipe Moura Araújo  Oliveira  Christiane Patrícia Feitosa  Affonso  Elizabeth Gusmão  Cruz  Claudinei  Tavares-Dias  Marcos 《Aquaculture International》2021,29(6):2477-2488

Aquaculture International - This study investigated the efficacy of trichlorfon against Neoechinorhynchus buttnerae, as well as its palatability, residue analysis, and the blood parameters of...  相似文献   

Optimum krill phospholipids content in microdiets for gilthead seabream (Sparus aurata) larvae     

R. Saleh  M.B. Betancor  J. Roo  T. Benítez‐Santana  C.M. Hernández‐Cruz  F.‐J. Moyano  M. Izquierdo 《Aquaculture Nutrition》2013,19(4):449-460

The aim of the present study was to determine the optimum dietary levels of krill phospholipids (KPL) for sea bream (Sparus aurata) larvae, and its influence on larval development and digestive enzymes activity. Larvae were fed five formulated microdiets with five different levels of KPL. Complete replacement of live preys with the experimental microdiets for seabream larvae produced high survival and growth rates, particularly in fish fed the highest levels of KPL. In the present study, increase in dietary KPL up to 120 g kg^?1 (100 g kg^?1 total PL) significantly improved larval survival and growth, whereas further increase did not improve those parameters. An increase in alkaline phosphatase, trypsin and lipase activity with the elevation of KPL up to 120 g kg^?1 was also found denoting a better functioning of digestive system. Besides, there was a linear substrate stimulatory effect of dietary KPL on phospholipase A2 activity. Finally, increasing dietary KPL lead to better assimilation of n‐3 HUFA especially eicosapentaenoic acid, reflected in the higher content of these fatty acids in both neutral and polar lipids of the larvae. In summary, KPL were found to be an excellent source of lipids for seabream larvae. Optimum inclusion levels of this ingredient in microdiets to completely substitute live preys at this larval age were found to be 120 g kg^?1 KPL.  相似文献   

Structural development of Pacific red snapper Lutjanus peru from hatching to the onset of first feeding          下载免费PDF全文

Iram Zavala‐Leal  Silvie Dumas  Edgar O. López‐Villegas  Renato Peña  Mauricio Contreras‐Olguín  Laura Flores‐Montijo  José De La Cruz‐Agüero 《Aquaculture Research》2015,46(5):1162-1174

Successful rearing of larval fish requires culture conditions and feeding strategies matching the ontogenetic status of larvae. This study describes the external morphology and development of organs and structures involved in the feeding process (i.e. sensorial organs, mouthparts and digestive system) from hatching until first feeding in Pacific red snapper. Hatching occurred 26 h after fertilization at 26°C and total length (TL) was 2.45 ± 0.08 mm. The larvae showed an undifferentiated eye and digestive tract. At 48 hah, TL was 3.31 ± 0.12 mm. Yolk and oil globule were still present. The mouth was still closed, but the Meckel's, quadrate, hyoid and hyomandibular cartilages were present. The retina was formed by 5 layers, and a thin layer of pigment epithelium was observed in the outer nuclear layer (ONL). At 70 hah, TL was 3.44 ± 0.22 mm. A remnant of oil globule was still present. The mouth and anus were open. At 93 hah, the number of cones in the ONL of the retina have increased and there was more pigment in the pigment epithelial layer. A joint between Meckel's and the quadrate cartilage and also a joint between the hyomandibular cartilage and the skull were present. The presence of live feed was detected in the digestive tract of these larvae. Based on these observations, the Pacific red snapper larvae is functional to start ingesting live feed between the 3rd and 4th day after hatching.  相似文献   

Evaluation of the Effective Inactivation of Enteric Bacteria and Viruses From Swine Effluent and Sludge at Tropical Temperatures     

Gislaine Fongaro  Airton Kunz  Maria Elisa Magri  Aline Viancelli  Camila Daminelli Schissi  Maria Célia da Silva Lanna  Marta Hernández  David Rodríguez-Lázaro  María Cruz García-González  Célia Regina Monte Barardi 《Water, air, and soil pollution》2018,229(7):226

The safe recycling of organic wastes such as the nutrients obtained from agriculture activities is a relevant aspect of the “One Health” strategy, a worldwide initiative including all aspects of health care for humans and animals, as well as aspects related to the conservation and development of the environment. It represents an important opportunity to mitigate the potential impact of microbial pathogens likely present in nutrient natural sources, as digestate, when applied to land as fertilizers. The objectives of the current study were to determine the inactivation of enteric microorganisms in swine digestate (effluent and sludge) during storage in anaerobic conditions and at different ambient temperatures of tropical zones (16, 22, and 37 °C). Human adenovirus 2 (HAdV-2), bacteriophage PhiX-174, and Salmonella enterica serovar typhimurium (S. typhimurium) were used as enteric microbial models to determine the minimum storage time required to reduce at least 3log of enteric microorganisms load in both matrices at the mentioned temperatures. The minimum storage time required for S. typhimurium was shorter than those observed for viruses at 37 °C, while reduction of at least 3log for S. typhimurium was observed after just 1 day; 20 and 90 days were needed for similar reductions for HAdV-2 and PhiX-174, respectively. Similar results were also observed at lower temperatures: 30 and 45 days were needed for S. typhimurium at 22 and 16 °C, respectively, but 30 and 90 days were needed at 22 °C for HAdV-2 PhiX-174, respectively, or 90 and 120 days at 16 °C for HAdV-2 PhiX-174, respectively. This is a pioneering study on the evaluation of inactivation of enteric viruses in swine digestate in usual tropical ambient temperatures; it demonstrates that the time for a considerable inactivation is longer than that observed for a enteric microorganisms (S. typhimurium), and shows that the storage of swine digestate at the referred temperatures can be used as a low-cost post-treatment to inactivate enteric microorganisms, allowing a further use as safer fertilizer.  相似文献   

Antimicrobial Resistance Genes in Pigeons from Public Parks in Costa Rica          下载免费PDF全文

K. Blanco‐Peña  F. Esperón  A. M. Torres‐Mejía  A. de la Torre  E. de la Cruz  M. Jiménez‐Soto 《Zoonoses and public health》2017,64(7):e23-e30

Antimicrobial resistance is known to be an emerging problem, but the extent of the issue remains incomplete. The aim of this study was to determine the presence or absence of nine resistance genes (bla_TEM, catI, mecA, qnrS, sulI, sulII, tet(A), tet(Q), vanA) in the faeces of 141 pigeons from four urban parks in Alajuela, Guadalupe, Tres Ríos and San José in Costa Rica. The genes were identified by real‐time PCR directly from enema samples. About 30% of the samples were positive for genes catI and sulI; between 13% and 17% were positive for qnrS, sulII, tet(A) and tet(Q); and 4% were positive for bla_TEM. The mecA and vanA genes were not detected. The average of antimicrobial resistance genes detected per pigeon was 2. Eight different patterns of resistance were identified, without differences in the sampling areas, being the most common pattern 2 (sulII positive samples). During rainy season, the genes more frequently found were sulI and tet(A). In conclusion, the urban inhabiting pigeons tested are currently carrying antimicrobial resistance genes, potentially acting as reservoirs of resistant bacteria and vectors to humans. To the authors’ knowledge, this is the first study carried out on direct detection of resistance genes in the digestive metagenomes of pigeons.  相似文献   

Undernutrition in the parental and first generation provokes an organ‐specific response to oxidative stress on neonates of second filial generation of Wistar rats          下载免费PDF全文

R. Baños‐Gómez  N. S. Cruz‐Cansino  T. Suarez‐Diéguez  C. Valadez‐Vega  E. Ramírez‐Moreno  E. Alanís‐García  J. A. Ariza‐Ortega  J. J. Manríquez‐Torres  E. Zamora‐Romo  L. Delgado‐Olivares 《Journal of animal physiology and animal nutrition》2017,101(2):267-274

Undernutrition induces an increase of the oxidative stress that can predispose offspring to various diseases in adulthood through epigenetic reprogramming. The aim of this study was to evaluate the effects of intergenerational undernutrition on protein oxidation and antioxidant defence response on liver, heart and brain of the second‐generation neonates (F₂) of undernourished rats. For this purpose, both parents in parental (F₀) and first generation (F₁) were fed with a low‐nutrient diet. Body mass and length decreased (p < 0.05) in F₀, F₁ and F₂ being the F₁ males who exhibited a greater mass loss. A decrease in plasma albumin concentration was observed in F₂ neonates (p < 0.05) and also a mass loss of liver, heart and brain (p < 0.05), although proportionally to body length reduction. Undernutrition increased levels of protein oxidation in liver and heart (p < 0.05) but not in brain (p > 0.05) while catalase activity increased only in brain (p < 0.05). In summary, intergenerational undernutrition modifies the antioxidant status through an organ‐specific response, on F₂ neonate rats, where the brain increased catalase activity to prevent a severe oxidative damage and support the vital functions of this key organ to maintain vital functions.  相似文献   

Reduction in susceptibility to Xanthomonas axonopodis pv. citri in transgenic Citrus sinensis expressing the rice Xa21 gene     

B. M. J. Mendes  S. C. Cardoso  R. L. Boscariol-Camargo  R. B. Cruz  F. A. A. Mourão Filho  A. Bergamin Filho 《Plant pathology》2010,59(1):68-75

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