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1.
Cristina Pascual Leticia Arena Gerard Cuzon Gabriela Gaxiola Gabriel Taboada Manuel Valenzuela Carlos Rosas 《Aquaculture (Amsterdam, Netherlands)》2004,230(1-4):405-416
Blood metabolites in wild and seventh-generation cultivated shrimp were measured to determine how size-based selection could alter the nutritional and immunological conditions of Litopenaeus vannamei. Wild L. vannamei juveniles and a sample of seventh-generation cultured shrimp were acclimated under identical conditions. During 55 days, shrimp were fed a high (HCHO: 44%) or a low (LCHO: 3%) carbohydrate diet for 55 days. Wild shrimp showed a direct relation between dietary CHO and lactate, protein and hemocyte levels indicating that dietary CHO was used for protein synthesis via transamination pathways. In seventh-generation cultured shrimp these parameters were inversely proportional to dietary CHO level, indicating the capacity to synthesize protein from dietary CHO was repressed in cultured shrimp. Farmed shrimp showed a limited capacity to respond to LCHO diets demonstrating high protein dependence in their metabolism and immune response. These results demonstrate that during size-based breeding programs other metabolic process than CHO catabolism can be selected. The incapacity of shrimp to use dietary CHO could limit protein reduction of diets and limit the efforts of the shrimp industry to be ecologically and environmentally profitable. 相似文献
2.
Ella Vázquez‐Domínguez Andrea Bolongaro‐Crevenna Adolfo Sánchez Carlos Rosas 《Aquaculture Research》2008,40(1):91-102
As a function of the water quality provided by square, circular and oval experimental ponds, the growth, survival and oxygen requirements in epibenthic postlarvae of Farfantepenaeus aztecus were analysed in relation to their routine metabolism and apparent heat increment. Temperature, oxygen concentration, pH and salinity were measured daily in two experimental ponds of each shape. The postlarvae oxygen consumption during two 24‐h cycles, their growth, physiological condition and survival and the productivity in the ponds were estimated. Low values of pH, oxygen concentration and phytobenthos productivity, and reduced postlarvae relative growth and survival were observed in the square ponds. We suggest that the latter results from a deficient water circulation related to the effect of the pond's shape on dissolved oxygen levels and, consequently, on growth and survival. The postlarvae routine metabolism, including feeding, varied between 1.91 and 2.25 mg O2 h?1 g?1 wet weight, whereas the minimum oxygen concentration needed in the ponds is approximately 4.25 mg O2 L?1. These conditions were achieved in the oval ponds concurrent with higher survival and growth values, in which individuals distributed randomly, for which we suggest that oval‐shaped ponds could be the most adequate for the culture of this and other penaeid species. 相似文献
3.
Intensive tillage for annual crop production may be affecting soil health and quality. However, tillage intensity effects on biological activities of volcanic-derived soils have not been systematically investigated. We evaluated the effects of three different tillage practices on some biological activities of an Ultisol from southern Chile during the third year of a wheat–lupin–wheat crop sequence. Treatments were: no tillage with stubble burning (NTB), no tillage without stubble burning (NT) and conventional tillage with disk-harrowing and stubble burning (CT). Biological activities were evaluated in winter and summer at 0–200 mm and at three soil depths (0–50, 50–100 and 100–200 mm) in winter. Total organic C and N were significantly higher under no-tillage systems than CT. In general, NT increased C and N of microbial biomass in comparison with CT, especially in winter. Microbial biomass C was closely associated with microbial biomass N (r = 0.986, P < 0.05); acid phosphomonoesterase (r = 0.999, P < 0.05); β-glucosidase (r = 0.978, P < 0.05), and others. Changes in biological activities occurred mainly in the upper soil layer (0–50 mm depth) in spite of the short duration of the experiment. Biological activities could be used as practical biological indicators to apply the more appropriate management systems for increasing soil sustainability or productivity. 相似文献
4.
de Mello DM da Silva V Rosas F 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2011,40(1):74-77
Background: Establishment of reference values for serum biochemical analytes is important for monitoring health and physiological status of captive animals. Objective: The purpose of this study was to measure and report ranges for serum biochemical analytes in Amazonian manatees (Trichechus inunguis). Methods: Blood samples were collected from 24 healthy captive Amazonian manatees that comprised a mixture of adults, subadults, and calves and males and females; serum analytes were measured and analyzed using a dry reagent bench‐top chemical analyzer. Comparisons were made between sexes and with previously published values of closely related species. Results: Medians and ranges (minimum–maximum) of values for the analytes were: lactate dehydrogenase (LDH), 151 (111–278) U/L (n=20); creatine kinase, 144 (76–315) U/L (n=11); alanine aminotransferase, 10 (2–28) U/L (n=18); aspartate aminotransferase, 14 (5–28) U/L (n=21); γ‐glutamyltransferase, 47 (36–73) U/L (n=21); amylase, 1428 (1010–1874) U/L (n=21); alkaline phosphatase, 73 (36–141) U/L (n=19); total protein, 6.8 (6.2–8.0) g/dL (n=24); albumin, 3.3 (2.6–4.1) g/dL (n=21); cholesterol, 188 (101–399) mg/dL (n=21); triglycerides, 126 (60–236) mg/dL (n=21); glucose, 47 (22–69) mg/dL (n=21); urea, 43 (21–69) mg/dL (n=21); uric acid, 1.1 (0.5–1.8) mg/dL (n=22); creatinine, 2.2 (1.5–3.3) mg/dL (n=22); total bilirubin, 0.2 (0.2–2.0) mg/dL (n=21); calcium, 12.7 (10.2–18.6) mg/dL (n=24); iron, 282 (207–457) μg/dL (n=13); and magnesium, 6.9 (4.3–8.9) mg/dL (n=20). With the exception of LDH, no differences were observed between sexes. Conclusions: The ranges obtained in this study provide important preliminary estimates for concentrations and activities of serum analytes in Amazonian manatees until a larger reference interval study can be conducted. 相似文献
5.
Campos FR Januário AH Rosas LV Nascimento SK Pereira PS França SC Cordeiro MS Toldo MP Albuquerque S 《Fitoterapia》2005,76(1):26-29
Crude extracts and fractions of Bertholletia excelsa stem barks were tested for trypanocidal activity. Acetone and methanol extracts showed significant in vitro trypanocidal activity against trypomastigote form of Trypanosoma cruzi since in the concentration of 500 microg/ml, the parasites were reduced in 100% and 90.3% respectively, whereas the triterpene betulinic acid pure isolated from hexane extract presented 75.4%. 相似文献
6.
Carlos Rosas Ariadna Sánchez Cristina Pascual Josué Aguila Teresita Maldonado Pedro Domingues 《Aquaculture International》2011,19(1):165-180
Octopus maya is a carnivorous species and protein is the main energy source. During the present study, two different dietary protein levels
(40 and 60% CP) were offered to octopuses as specifically designed artificial diets, to determine protein needs and the effects
on metabolism. Frozen crab (Callinectes spp.) was used as control. Results obtained demonstrated that crab remains as one of the best diets for O. maya. The artificial diet with 60% CP produced a low but positive growth rate, and at times, a physiological response similar
to that observed in octopuses fed crabs. The present results show the capacity of O. maya juveniles to adjust their digestive enzymes to different types of food and protein level, and this appears to be well correlated
with octopus growth. General proteases and trypsin from the pancreas were well correlated with growth rates. A low activity
was observed in octopuses fed 40% PC diet (negative growth rate), while a high activity was present in octopuses fed 60% CP
diet and crabs (low and high growth rate, respectively). In contrast, these same enzymes were inducted in the salivary glands
of octopuses fed with the diet that promoted weight loss (40% CP diet), while a reduced activity was observed in octopuses
fed crabs. Energy budget indicates that the animals ingested more than 1,000 kJ week−1 kg−1; with such energy, octopuses should satisfy their physiological demands such as was observed when animals were fed crab (I = 1,300 kJ week−1 kg−1; P = 834 kJ week−1 kg−1). However, a very low digested energy was observed in octopuses the fed artificial diets, indicating that these could have
a factor that limits digestibility. 相似文献
7.
Particulate matter concentrations were measured in five size ranges, during an annual period, at the National University Campus in Mexico City. Size distribution indicated high particulates values in the size ranges from 3.0 to >7.2 μm and from 0.49 to 1.5 μm. The cascade impactor concentration represented 30% of the total suspended particles (TSP) values, with a correlation of 0.6 between them. No significative seasonal difference in the mass paniculate size distrubition was found, but in the rainy season a slight increase in fine particles with respect to the total mass impactor was found. The application of a respiratory model showed that maximum mass of coarse particulates deposition in the thoracic region was of 27 μg hr?1. The highest concentration of fine particulates deposition reached only 13 μg hr?1, in activity. 相似文献
8.
Pedro Domingues Ana Ferreira Lorenzo Marquez José P. Andrade Nelda López Carlos Rosas 《Aquaculture International》2008,16(3):215-229
The effects of feeding three natural frozen diets, grass shrimp (Palaemonetes sp.), crayfish (Procambarus clarkii) and fish (Sardina pilchardus) and two semi-humid artificial diets (based on fish powder) to mature cuttlefish, Sepia officinalis, were analysed. Growth and feeding rates (GR and FR, % BW day−1), food conversions (FC, %), and total protein and lipid composition of the diets were determined. Digestive gland to body
weight ratio and absorption efficiency were calculated for each diet. Cuttlefish fed shrimp and crayfish grew larger (1.5
and 1.1% BW day−1, respectively) compared to the other diets. Shrimp promoted the highest FC, followed by crayfish, and sardine. The highest
FR was obtained for cuttlefish fed crayfish (8.4% BW day−1). Although both artificial diets were accepted, none produced growth. A positive correlation (r = 0.96) between cuttlefish ingestion rate and digestive gland weight was obtained. Some cannibalism occurred among cuttlefish
fed the artificial diets during the last week of the experiment. According to the results obtained, P. clarkii could be used as an alternative prey to shrimp for rearing adult mature (>50 g) S. officinalis. 相似文献
9.
Giulia Del Vecchio Francisco Otero‐Ferrer Cristina Pascual Carlos Rosas Nuno Simoes Maite Mascar 《Aquaculture Research》2019,50(12):3729-3740
This study assessed the effect of starvation on survival and nutritional status of newborn juveniles H. erectus (<10 days) to optimize rearing protocols, thereby helping to reduce wildlife exploitation. Maximum starvation time (MST) was estimated through the survival of juveniles continuously starved from birth. Resistance to starvation and the effect of food re‐introduction after 1, 2, 4 and 6 days of starvation on survival and metabolite concentrations (total proteins, total lipids, acylglycerides, cholesterol, glucose) were also determined. Survival amongst continuously starved animals decreased from 6.6 ± 0.5 to 0% from days 9 to 10 of starvation. Seahorses under different starvation–refeeding treatments all had 100% survival up to day 5 of experiments. After 10 days, however, a 4‐day starvation period followed by refeeding showed negative effects with <50% survival. During continuous starvation, lipids were the first energy reserve used to maintain basal metabolism, followed by proteins. Except for cholesterol, all metabolite concentrations differed between continuous starvations and feeding. Despite high seahorse survival after 5 days in the absence of food, the recovery of the metabolic status is possible after a starvation period of no more than 2 days, since irreversible physiological changes compromising the ultimate survival of the organisms take place after this time. 相似文献
10.
O. Gonzales-Viera J. Marigo V. Ruoppolo F.C.W. Rosas C.T. Kanamura C. Takakura A. Fernández J.L. Catão-Dias 《Veterinary parasitology》2013,191(3-4):358-362
This study describes toxoplasmosis in a by caught Guiana dolphin (Sotalia guinensis) from Paranaguá Bay, Paraná, Brazil. Interstitial pneumonia, multisystemic arteritis, multifocal adrenalitis and hepatitis were the primary lesions observed. These tissues had moderate to severe necrosis and mononuclear cells infiltration usually surrounded by tachyzoites and tissue cysts. Moderate lymphoid depletion was evident in the spleen. Toxoplasma gondii was positive by immunohistochemical and ultrastructural evaluation. Furthermore, the animal was negative for Morbillivirus by immunohistochemistry and had low levels of persistent organochlorines. There is evidence of environmental changes in the Paranaguá Bay that could justify the occurrence of toxoplasmosis in Guiana dolphin. The sewage run-off from main urban areas and the presence of domestic and wild felids in areas surrounding the bay could be a source of T. gondii oocysts from land to sea. Based on its habitat, the authors recommend this dolphin species as sentinels for the health of bays and estuaries where they occur. 相似文献