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1.
Braz J Biol ; 84: e280240, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38695422

RESUMEN

Transporting live fish is a common practice in fish farming, and is certainly one of the main problems that affect fish homeostasis. In this scenario, the use of natural additives has shown promise in improving fish resistance to adverse situations. This study aimed to assess the impact of Ocimum gratissimum L. essential oil (OGEO) on water quality, hematological parameters, and residue levels in the plasma, fillet, and liver of juvenile piraputanga (Brycon hilarii) during a two-hour transportation period. The fish were divided into plastic bags (4 L) and exposed to three different OGEO concentrations (10, 20, and 30 mg L-1), while a control group received no OGEO (three repetitions each). After the two-hour transportation, blood samples were collected, as well as portions of the fillet and liver for quantifying essential oil compounds, which were also measured in the plasma. Oxygen levels remained high throughout the transportation period, in all groups, while the pH decreased. Hemoglobin, MCHC, and MCH increased in fish exposed to OGEO concentrations of 20 and 30 mg L-1, compared to the control group. However, lymphocyte counts and the concentrations of essential oil compounds in plasma, fillet, and liver increased with higher OGEO concentrations. The use of 10 mg L-1 OGEO in the two-hour transport water is promising to ensure the survival and well-being of Brycon hilarii juveniles (weighing 16 g), showing to be safe and effective. The residual concentration of eugenol the major compound of OGEO in the fillet remains below the maximum limit of the recommended daily intake.


Asunto(s)
Hígado , Ocimum , Aceites Volátiles , Calidad del Agua , Animales , Ocimum/química , Aceites Volátiles/química , Hígado/química , Hígado/efectos de los fármacos , Transportes , Characiformes/sangre , Contaminantes Químicos del Agua/análisis
3.
Animal ; 14(S3): s438-s452, 2020 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-32778195

RESUMEN

Accurate estimates of methane (CH4) production by cattle in different contexts are essential to developing mitigation strategies in different regions. We aimed to: (i) compile a database of CH4 emissions from Brazilian cattle studies, (ii) evaluate prediction precision and accuracy of extant proposed equations for cattle and (iii) develop specialized equations for predicting CH4 emissions from cattle in tropical conditions. Data of nutrient intake, diet composition and CH4 emissions were compiled from in vivo studies using open-circuit respiratory chambers, SF6 technique or the GreenFeed® system. A final dataset containing intake, diet composition, digestibility and CH4 emissions (677 individual animal observations, 40 treatment means) obtained from 38 studies conducted in Brazil was used. The dataset was divided into three groups: all animals (GEN), lactating dairy cows (LAC) and growing cattle and non-lactating dairy cows (GCNL). A total of 54 prediction equations available in the literature were evaluated. A total of 96 multiple linear models were developed for predicting CH4 production (MJ/day). The predictor variables were DM intake (DMI), gross energy (GE) intake, BW, DMI as proportion of BW, NDF concentration, ether extract (EE) concentration, dietary proportion of concentrate and GE digestibility. Model selection criteria were significance (P < 0.05) and variance inflation factor lower than three for all predictors. Each model performance was evaluated by leave-one-out cross-validation. The Intergovernmental Panel on Climate Change (2006) Tier 2 method performed better for GEN and GCNL than LAC and overpredicted CH4 production for all datasets. Increasing complexity of the newly developed models resulted in greater performance. The GCNL had a greater number of equations with expanded possibilities to correct for diet characteristics such as EE and NDF concentrations and dietary proportion of concentrate. For the LAC dataset, equations based on intake and animal characteristics were developed. The equations developed in the present study can be useful for accurate and precise estimation of CH4 emissions from cattle in tropical conditions. These equations could improve accuracy of greenhouse gas inventories for tropical countries. The results provide a better understanding of the dietary and animal characteristics that influence the production of enteric CH4 in tropical production systems.


Asunto(s)
Dieta , Lactancia , Metano , Alimentación Animal/análisis , Animales , Brasil , Bovinos , Dieta/veterinaria , Ingestión de Energía , Femenino , Metano/análisis , Leche/química
4.
Sci Total Environ ; 689: 1133-1140, 2019 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-31466153

RESUMEN

The effects of divergent phenotypic classification in crossbreed Holstein × Gyr dairy heifers for methane emissions in relation to performance, digestibility, energy and nitrogen partition, blood metabolites and temperature of body surface were evaluated. Thirty-five heifers were classified as high and low emission for CH4 production (g/day), yield (g/kg dry matter intake) and intensity (g/kg average daily gain). Digestibility was evaluated by total collection of feces and urine. Gas exchanges were obtained in open-circuit respiratory chambers. A completely randomized design was used and divergent groups were compared by Fisher's test. No differences were found in intake traits between groups of CH4 production and intensity. The low yield group had higher intake. For digestibility and temperature at different body sites were no differences between variables. High production group had higher energy losses as methane and heat production. Low intensity group had higher digestible energy, energy balance and ratio between metabolizable and digestible energy. Urinary nitrogen was 14.3% lower for low production group. There was a difference between methane yield divergent groups for nitrogen intake, digestible and retained. Energy and nitrogen partitioning traits are correlated to the animals divergent for methane production and yield. The low production group presented lower blood insulin concentration. It was not possible to identify divergent animals for CH4 emission using the infrared thermography technique.


Asunto(s)
Metabolismo Energético , Metano/metabolismo , Animales , Bovinos , Heces , Femenino
5.
Phys Rev E ; 99(1-1): 012129, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30780247

RESUMEN

In this work we consider the nonequilibrium mechanical and magnetic work performed on a one-dimensional compressible Ising model. In the harmonic approximation we easily integrate the mechanical degrees of freedom of the model, and the resulting effective Hamiltonian depends on two external parameters, the magnetic field and the force applied along the chain. As the model is exactly soluble in one dimension we can determine the free energy difference between two arbitrary thermodynamic states of the system. We show the validity of the Jarzynski equality, which relates the free energy difference between two thermodynamic states of the system and the average work performed by external agents in a finite time, through nonequilibrium paths between the same thermodynamic states. We have found that the Jarzynski theorem remains valid for all the values of the rate of variation of the magnetic field and the mechanical force applied to the system.

6.
Phys Rev E ; 97(4-1): 042121, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29758686

RESUMEN

In this paper we determine the nonequilibrium magnetic work performed on a Ising model and relate it to the fluctuation theorem derived some years ago by Jarzynski. The basic idea behind this theorem is the relationship connecting the free energy difference between two thermodynamic states of a system and the average work performed by an external agent, in a finite time, through nonequilibrium paths between the same thermodynamic states. We test the validity of this theorem by considering the one-dimensional Ising model where the free energy is exactly determined as a function of temperature and magnetic field. We have found that the Jarzynski theorem remains valid for all the values of the rate of variation of the magnetic field applied to the system. We have also determined the probability distribution function for the work performed on the system for the forward and reverse processes and verified that predictions based on the Crooks relation are equally correct. We also propose a method to calculate the lag between the current state of the system and that of the equilibrium based on macroscopic variables. We have shown that the lag increases with the sweeping rate of the field at its final value for the reverse process, while it decreases in the case of the forward process. The lag increases linearly with the size of the chain and with a slope decreasing with the inverse of the rate of variation of the field.

7.
J Fish Biol ; 92(6): 1902-1914, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29624697

RESUMEN

Myleus pachyodus, a new serrasalmid species, is described from the Rio Teles Pires and Rio Jamanxim, both tributaries of the Rio Tapajós in Mato Grosso and Pará states, Brazil. The new species differs from all congeners by having a remarkable ontogenetic thickening of the teeth shifting from slender incisiform in juveniles to thick bulky teeth at standard length ≥ 100 mm, whereas congeners present slender, antero-posteriorly flat teeth throughout all life stages. The new species further differs from congeners by having 18-20 branched dorsal-fin rays, by the lack of a diastema between contralateral outer series of premaxillary teeth and by the presence of 16-25 prepelvic spines, with the anteriormost spine never reaching the vertical through the pectoral-fin origin.


Asunto(s)
Characiformes/anatomía & histología , Characiformes/clasificación , Animales , Biodiversidad , Brasil , Conservación de los Recursos Naturales , Femenino , Masculino , Pigmentación , Ríos , Caracteres Sexuales , Diente/anatomía & histología
8.
J Dairy Sci ; 101(6): 5060-5068, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29525309

RESUMEN

The aims of this study were (1) to assess if there is phenotypical divergence for feed efficiency (FE) during the preweaning phase; (2) if FE is correlated with heat production (HP) measured by the face mask method or (3) by surface skin temperature via thermography, and (4) whether these methods are applicable to preweaned calves. Holstein × Gyr heifer calves (n = 36, birth body weight = 32.4 ± 6.6 kg) were enrolled and on trial between 4 and 12 wk of age and were classified into 2 residual feed intake (RFI) and residual body weight gain (RG) groups: high efficiency (HE; RFI, n = 10; and RG, n = 9) and low efficiency (LE; RFI, n = 10; and RG, n = 8). Calves were fed milk (6 L/d) and solid feed (95% starter and 5% chopped Tifton 85 hay, as fed). Growth was monitored weekly and feed intake (milk and solid feed) daily, during the whole period. Gas exchanges (O2 consumption and production of CO2 and CH4) were obtained using a face mask at 45 ± 5 d of age and HP was estimated. Maximum temperatures were measured at 7 sites with an infrared camera at 62 ± 7 d of age. There was divergence in RFI and RG. Respectively, HE and LE calves had RFI of -0.14 and 0.13 kg/d, and RG of 0.05 and -0.07 kg/d. Dry matter intake was 15% lower in HE-RFI compared with LE-RFI, but no differences were observed in average daily weight gain. Within the RG test, no differences were observed in dry matter intake or average daily gain. The HE-RFI calves consumed less O2 (L/d) and produced less CO2 (L/d). Heart rate and HP were lower for HE-RFI calves compared with LE-RFI. Residual feed intake was correlated with HP (r = 0.48), O2 consumption (r = 0.48), CO2 production (r = 0.48), and heart rate (r = 0.40). No differences were observed in HP and gas exchanges between RG groups. Methane production was null in both groups. Eye temperature measured by thermography was 0.5°C greater in HE-RG than LE-RG calves. Differences in skin temperature between HE and LE calves were not observed at the other sites. These results support the hypothesis that calves are divergent for RFI, RG, and FE during preweaning and divergence tests are applicable during this phase. The face mask method described here is a useful tool for estimating differences in HP among phenotypically divergent RFI calves. Eye temperature measured by infrared thermography may have potential to screen phenotypically divergent RG calves.


Asunto(s)
Bovinos/fisiología , Termogénesis , Alimentación Animal/análisis , Animales , Temperatura Corporal , Dieta/veterinaria , Ingestión de Alimentos/fisiología , Femenino , Frecuencia Cardíaca , Masculino , Leche/metabolismo , Termografía , Destete , Aumento de Peso
9.
J Dairy Sci ; 101(5): 4221-4234, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29477520

RESUMEN

Plant extracts have been proposed as substitutes for chemical feed additives due to their potential as rumen fermentation modifiers and because of their antimicrobial and antioxidant activities, possibly reducing methane emissions. This study aimed to evaluate the use of oregano (OR), green tea extracts (GT), and their association as feed additives on the performance and methane emissions from dairy between 28 and 87 d of lactation. Thirty-two lactating dairy cows, blocked into 2 genetic groups: 16 Holstein cows and 16 crossbred Holstein-Gir, with 522.6 ± 58.3 kg of body weight, 57.2 ± 20.9 d in lactation, producing 27.5 ± 5.0 kg/cow of milk and with 3.1 ± 1.8 lactations were evaluated (means ± standard error of the means). Cows were allocated into 4 treatments: control (CON), without plant extracts in the diet; oregano extract (OR), with the addition of 0.056% of oregano extract in the dry matter (DM) of the diet; green tea (GT), with the addition of 0.028% of green tea extract in the DM of the diet; and mixture, with the addition of 0.056% oregano extract and 0.028% green tea extract in the DM of the diet. The forage-to-concentrate ratio was 60:40. Forage was composed of corn silage (94%) and Tifton hay (6%); concentrate was based on ground corn and soybean meal. Plant extracts were supplied as powder, which was previously added and homogenized into 1 kg of concentrate in natural matter, top-dressed onto the total mixed diet. No treatment by day interaction was observed for any of the evaluated variables, but some block by treatment interactions were significant. In Holstein cows, the mixture treatment decreased gross energy and tended to decrease the total-tract apparent digestibility coefficient for crude protein and total digestible nutrients when compared with OR. During the gas measurement period, GT and OR increased the digestible fraction of the ingested DM and decreased CH4 expressed in grams per kilogram of digestible DMI compared with CON. The use of extracts did not change rumen pH, total volatile fatty acid concentration, milk yield, or most milk traits. Compared with CON, oregano addition decreased fat concentration in milk. The use of plant extracts altered some milk fatty acids but did not change milk fatty acids grouped according to chain length (short or long), saturation (unsaturated or saturated), total conjugated linoleic acids, and n-3 and n-6 contents. Green tea and oregano fed separately reduced gas emission in cows during the first third of lactation and have potential to be used as feed additives for dairy cows.


Asunto(s)
Camellia sinensis/química , Bovinos/metabolismo , Metano/análisis , Origanum/metabolismo , Extractos Vegetales/metabolismo , Alimentación Animal/análisis , Animales , Camellia sinensis/metabolismo , Bovinos/crecimiento & desarrollo , Dieta/veterinaria , Digestión , Ácidos Grasos Volátiles/análisis , Ácidos Grasos Volátiles/metabolismo , Femenino , Aditivos Alimentarios/análisis , Aditivos Alimentarios/metabolismo , Lactancia , Metano/metabolismo , Leche/química , Leche/metabolismo , Extractos Vegetales/análisis , Rumen/metabolismo , Ensilaje/análisis , Zea mays/metabolismo
10.
J Fish Biol ; 92(2): 515-522, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-29431224

RESUMEN

A new species of Curimatopsis is described from the Rio Nhamundá, Amazon basin in northern Brazil. The new species is distinguished from congeners by the presence of a distinctive concentration of dark pigmentation over the entire lower lobe of the caudal fin, reticulate pattern of body pigmentation, lower jaw longer than and overlapping the anterior portion of the upper jaw, crescent-shaped posterior nostril and by morphometric and meristic data. Comments on the phylogenetic position of the new species within Curimatopsis are also provided.


Asunto(s)
Characiformes/anatomía & histología , Characiformes/clasificación , Animales , Biodiversidad , Brasil , Characiformes/genética , Femenino , Masculino , Filogenia , Pigmentación , Ríos
12.
Genet Mol Res ; 16(2)2017 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-28481405

RESUMEN

Single nucleotide polymorphisms (SNPs) are the best genetic markers for associative studies of the immune system in invertebrates. In the marine shrimp Litopenaeus vannamei, SNPs linked to disease resistance have been reported for some genes, such as hemocyanin, anti-lipopolysaccharide factor, and heat-shock protein 70 (Hsp70). In the present study, polymorphisms in the Hsp70 gene were investigated among three commercial L. vannamei populations bred in Northeast and South Brazil. The first population withstood a strong white spot disease outbreak; the second population suffered extended exposure to infectious myonecrosis; the third population was a high health population, which was experimentally infected with white spot syndrome virus (WSSV) in the present study. All five previously known SNPs (C661A, T712C, C782T, C892T, and C1090T) were detected in the coding region of Hsp70, by Sanger sequencing of 119 shrimp. Significant differences in genetic and genotype frequencies among populations were observed for C661A, C892T, and C1090T. In the population submitted to WSSV challenge, no frequency differences were found between dead and surviving shrimp groups. These results indicate that the Hsp70 polymorphisms described here cannot be associated with WSSV tolerance. However, significant frequency differences were observed for the population exposed to infectious myonecrosis virus. This is the first time that L. vannamei Hsp70 gene polymorphisms were studied in correlation with these important shrimp viruses.


Asunto(s)
Proteínas HSP70 de Choque Térmico/genética , Penaeidae/genética , Polimorfismo de Nucleótido Simple , Animales , Acuicultura , Frecuencia de los Genes , Genotipo , Penaeidae/virología
13.
J Fish Biol ; 88(2): 459-76, 2016 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-26660534

RESUMEN

Two new species of Hyphessobrycon are described from the headwaters of the Tapajós and Xingu River basins, Pará, Brazil. Both new species can be distinguished from congeners by the presence of a vertically elongate humeral blotch, a conspicuous round to vertically oblong caudal-peduncle blotch not extending onto the distal portions of the middle caudal-fin rays, a conspicuous blotch on the central portion of the third infraorbital immediately ventral to the eye, the lack of a conspicuous longitudinal stripe and the lack of sexual dimorphism in the extension of the caudal-peduncle blotch. Hyphessobrycon delimai n. sp. can be distinguished from Hyphessobrycon krenakore n. sp. by the extent of the caudal-peduncle blotch which extends across most of the caudal-peduncle depth (v. restricted to the middle portion of the caudal peduncle), the presence of dark chromatophores uniformly scattered along the length of the interradial membranes of the dorsal, anal and caudal fins (v. concentrated on the distal one-half or one-fourth of the interradial membranes) and the absence of small bony processes on the pelvic and anal fins of mature males (v. small bony processes present).


Asunto(s)
Characidae/anatomía & histología , Characidae/clasificación , Aletas de Animales/anatomía & histología , Animales , Brasil , Femenino , Masculino , Ríos , Diente/anatomía & histología
14.
Artículo en Inglés | MEDLINE | ID: mdl-26465450

RESUMEN

The effect of diffusion in the one-dimensional long-range contact process is investigated by mean-field calculations. Recent works have shown that diffusion decreases the effectiveness of long-range interactions, affecting the character of the phase transition: for higher values of the diffusion coefficient, stronger long-range interactions are required to enable phase coexistence and first-order behavior. Here we apply a generalized mean-field approximation for the master equation of the model that considers states of an aggregate of L lattice sites. The phase diagram of the model for values of L up to 10 is obtained, and for some values of the diffusion rate extrapolations to infinite-sized systems are given. For low-diffusive systems, approximations with L≥3 are able to reveal the suppression of the phase coexistence induced by diffusion, however, in the high-diffusion regime, larger values of L are necessary to correctly account for the higher range of correlations. We present a very efficient method to study the mean-field equations and determine the nature of the phase transitions that may be of general utility.

15.
Hum Exp Toxicol ; 34(6): 612-9, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25632967

RESUMEN

AIM: To investigate whether lycopene can modulate adiponectin levels and SIRT1 and FoxO1 gene expression in the adipose tissue of diet-induced obese rats. METHODS: Male Wistar rats were first fed with hypercaloric diet (HD, n = 12) for 6 weeks, and afterward, these rats were randomly assigned to receive HD (n = 6) or HD with lycopene-rich tomato oleoresin (equivalent to lycopene 10 mg/kg body weight (BW)/day, HD + L, n = 6) by gavage for additional 6 weeks. Plasma lycopene and adiponectin levels were analyzed by high-performance liquid chromatography and immunoassay, respectively. The messenger RNA (mRNA) expressions of adiponectin, Sirtuin 1 (SIRT1), Forkhead box O 1 (FoxO1), fatty acid translocase/cluster of differentiation 36 (FAT/CD36), and PPARγ in adipose tissues were determined by quantitative polymerase chain reaction. RESULTS: Lycopene was detected in the plasma of rats in HD + L group but not in the HD group. Although both BW and adiposity were not different between the two groups, there was a significant increase in both plasma concentration and mRNA expression of adiponectin in the adipose tissue of the HD + L group. In addition, the lycopene supplementation upregulated mRNA expressions of SIRT1, FoxO1, and FAT/CD36 but downregulated PPARγ in adipose tissue of obese rats. CONCLUSION: These data suggest that lycopene, in the concentration used, is not toxic and also its health benefits in adipose tissue may play a role against obesity-related complications.


Asunto(s)
Tejido Adiposo/efectos de los fármacos , Carotenoides/farmacología , Obesidad/metabolismo , Extractos Vegetales/farmacología , Solanum lycopersicum , Adiponectina/sangre , Adiponectina/genética , Tejido Adiposo/metabolismo , Animales , Carotenoides/sangre , Carotenoides/farmacocinética , Factores de Transcripción Forkhead/genética , Licopeno , Masculino , Proteínas del Tejido Nervioso/genética , Obesidad/sangre , PPAR gamma/genética , ARN Mensajero/metabolismo , Ratas Wistar , Sirtuina 1/genética
16.
Transplant Proc ; 46(6): 1753-6, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25131028

RESUMEN

INTRODUCTION: Although infection with extended-spectrum ß-lactamase-producing Enterobacteriaceae (ESBL-E) has been recognized as an important cause of morbidity after solid organ transplantation, there are limited data on the outcome of this complication among transplant recipients. The objective of this study was to describe the outcome and factors associated with mortality among recipients of abdominal solid organ transplants with bloodstream infection caused by ESBL-E. PATIENTS AND METHODS: This study was a retrospective analysis of a case series of patients who had bacteremia caused by ESBL-E after undergoing renal or liver transplantation between January 2000 and September 2008 at a university-affiliated hospital in Rio de Janeiro, Brazil. The primary end point of the study was death within 30 days of the diagnosis of bacteremia. RESULTS: During the study period, 997 subjects underwent kidney (759 patients) or liver (238 patients) transplantation. Fifty-four episodes of bacteremia caused by ESBL-E were diagnosed in 39 patients (4%). Mortality after the first episode of ESBL-E bacteremia was 26% (10 deaths). In multiple logistic regression analysis, the Pitt bacteremia score (P = .005) and being on mechanical ventilation at the time of infection diagnosis (P = .02) were the only variables associated with mortality. Thirteen episodes of recurrent bacteremia occurred in 8 (28%) of the 29 patients who survived the first episode. Two (25%) of these 8 patients died during the course of a recurrent episode. CONCLUSIONS: Bacteremia caused by ESBL-E was associated with high mortality and high risk of recurrence. Factors associated with clinical severity at the time of infection diagnosis were the main predictors of mortality.


Asunto(s)
Bacteriemia/mortalidad , Infecciones por Enterobacteriaceae/mortalidad , Trasplante de Órganos , Complicaciones Posoperatorias/mortalidad , Adulto , Anciano , Bacteriemia/etiología , Bacteriemia/terapia , Biomarcadores/metabolismo , Terapia Combinada , Enterobacteriaceae/metabolismo , Infecciones por Enterobacteriaceae/etiología , Infecciones por Enterobacteriaceae/terapia , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias/terapia , Recurrencia , Estudios Retrospectivos , Factores de Riesgo , Resultado del Tratamiento , beta-Lactamasas/metabolismo
17.
J Fish Biol ; 84(5): 1539-50, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24773543

RESUMEN

A new species of Rhinopetitia is described from the Rio Teles Pires, a major tributary of the Rio Tapajós. The new taxon is distinguished from its only congener, Rhinopetitia myersi, by having all premaxillary teeth in both rows with seven to nine cusps, maxillary teeth with seven or eight cusps, a distinct dark midlateral stripe on the body and a round humeral blotch (v. outer series of premaxillary teeth with three cusps and inner series of premaxillary teeth with three to five cusps, maxillary teeth with three to five cusps, the absence of a dark midlateral stripe and humeral blotch). Putative characters suggesting a close relationship between Rhinopetitia, Bryconacidnus, Ceratobranchia, Monotocheirodon, Odontostoechus, Othonocheirodus and Rhinobrycon are presented. This putative clade is included in the Stevardiinae, a monophyletic group within the Characidae.


Asunto(s)
Characidae/anatomía & histología , Characidae/clasificación , Animales , Brasil , Femenino , Masculino , Ríos , Caracteres Sexuales
18.
Hum Exp Toxicol ; 33(7): 748-60, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24275640

RESUMEN

The mechanism of doxorubicin (DOX)-induced cardiotoxicity remains controversial. Wistar rats (n = 66) received DOX injections intraperitoneally and were randomly assigned to 2 experimental protocols: (1) rats were killed before (-24 h, n = 8) and 24 h after (+24 h, n = 8) a single dose of DOX (4 mg/kg body weight) to determine the DOX acute effect and (2) rats (n = 58) received 4 injections of DOX (4 mg/kg body weight/week) and were killed before the first injection (M0) and 1 week after each injection (M1, M2, M3, and M4) to determine the chronological effects. Animals used at M0 (n = 8) were also used at moment -24 h of acute study. Cardiac total antioxidant performance (TAP), DNA damage, and morphology analyses were carried out at each time point. Single dose of DOX was associated with increased cardiac disarrangement, necrosis, and DNA damage (strand breaks (SBs) and oxidized pyrimidines) and decreased TAP. The chronological study showed an effect of a cumulative dose on body weight (R = -0.99, p = 0.011), necrosis (R = 1.00, p = 0.004), TAP (R = 0.95, p = 0.049), and DNA SBs (R = -0.95, p = 0.049). DNA SBs damage was negatively associated with TAP (R = -0.98, p = 0.018), and necrosis (R = -0.97, p = 0.027). Our results suggest that oxidative damage is associated with acute cardiotoxicity induced by a single dose of DOX only. Increased resistance to the oxidative stress is plausible for the multiple dose of DOX. Thus, different mechanisms may be involved in acute toxicity versus chronic toxicity.


Asunto(s)
Antibióticos Antineoplásicos/toxicidad , Doxorrubicina/toxicidad , Cardiopatías/inducido químicamente , Miocitos Cardíacos/efectos de los fármacos , Estrés Oxidativo/efectos de los fármacos , Animales , Antibióticos Antineoplásicos/administración & dosificación , Antioxidantes/metabolismo , Roturas del ADN , Doxorrubicina/administración & dosificación , Esquema de Medicación , Cardiopatías/metabolismo , Cardiopatías/patología , Inyecciones Intraperitoneales , Masculino , Miocitos Cardíacos/metabolismo , Miocitos Cardíacos/patología , Necrosis , Ratas Wistar , Factores de Tiempo
19.
Arq. bras. med. vet. zootec ; 65(3): 675-680, jun. 2013. tab
Artículo en Portugués | VETINDEX | ID: vti-9692

RESUMEN

Avaliou-se o efeito da inclusão do farelo de manga em substituição ao milho moído em dietas para ovinos sobre o consumo de nutrientes e de frações fibrosas, o ganho de peso e a conversão alimentar. Estudou-se também o benefício líquido e a taxa de retorno do custo total da dieta. Foram utilizados 24 cordeiros Santa Inês, distribuídos em delineamento inteiramente ao acaso, com quatro tratamentos, constituídos pelas porcentagens de inclusão do farelo de manga, em substituição ao milho, de 0, 33, 66 e 100%, e seis repetições. Não houve efeito da inclusão do farelo de manga sobre o consumo de nutrientes e o ganho de peso dos animais. Verificou-se efeito quadrático (P<0,05) da porcentagem de inclusão do farelo de manga sobre a conversão alimentar. O farelo de manga pode substituir o milho em dietas para ovinos sem comprometer o consumo e o ganho de peso e reduz o custo da alimentação, o que sugere ser ele um alimento alternativo para ovinos em confinamento.(AU)


The effect of inclusion of mango meal to replace corn in sheep diets was evaluated. The variables evaluated were the consumption of nutrients and fibre fractions, weight gain and feed conversion. In addition, a study of the net benefit and rate of return on the total cost of the diets was conducted. Twenty-four lambs Santa Inês, distributed in a completely randomized design with four treatments, consisting of the inclusion levels of mango meal replacing corn (0, 33, 66 and 100%) and six repetitions. There was no effect of the inclusion levels of mango meal on nutrients intake and weight gain of animals. There was a quadratic effect (P<0.05) of inclusion levels of mango meal on feed conversion. The mango meal can replace corn in diets without compromising intake and weight gain, while reducing the cost of feed, indicating the possibility of alternative use as feed for confined sheep.(AU)


Asunto(s)
Animales , Alimentación Animal/análisis , Mangifera , Aumento de Peso/fisiología , Ovinos/clasificación
20.
Arq. bras. med. vet. zootec ; Arq. bras. med. vet. zootec. (Online);65(3): 675-680, June 2013. tab
Artículo en Portugués | LILACS | ID: lil-679097

RESUMEN

Avaliou-se o efeito da inclusão do farelo de manga em substituição ao milho moído em dietas para ovinos sobre o consumo de nutrientes e de frações fibrosas, o ganho de peso e a conversão alimentar. Estudou-se também o benefício líquido e a taxa de retorno do custo total da dieta. Foram utilizados 24 cordeiros Santa Inês, distribuídos em delineamento inteiramente ao acaso, com quatro tratamentos, constituídos pelas porcentagens de inclusão do farelo de manga, em substituição ao milho, de 0, 33, 66 e 100%, e seis repetições. Não houve efeito da inclusão do farelo de manga sobre o consumo de nutrientes e o ganho de peso dos animais. Verificou-se efeito quadrático (P<0,05) da porcentagem de inclusão do farelo de manga sobre a conversão alimentar. O farelo de manga pode substituir o milho em dietas para ovinos sem comprometer o consumo e o ganho de peso e reduz o custo da alimentação, o que sugere ser ele um alimento alternativo para ovinos em confinamento.


The effect of inclusion of mango meal to replace corn in sheep diets was evaluated. The variables evaluated were the consumption of nutrients and fibre fractions, weight gain and feed conversion. In addition, a study of the net benefit and rate of return on the total cost of the diets was conducted. Twenty-four lambs Santa Inês, distributed in a completely randomized design with four treatments, consisting of the inclusion levels of mango meal replacing corn (0, 33, 66 and 100%) and six repetitions. There was no effect of the inclusion levels of mango meal on nutrients intake and weight gain of animals. There was a quadratic effect (P<0.05) of inclusion levels of mango meal on feed conversion. The mango meal can replace corn in diets without compromising intake and weight gain, while reducing the cost of feed, indicating the possibility of alternative use as feed for confined sheep.


Asunto(s)
Animales , Aumento de Peso/fisiología , Mangifera , Alimentación Animal/análisis , Ovinos/clasificación
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