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1.
Poult Sci ; 100(2): 654-662, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33518119

RESUMO

Large variations in hatching egg incubation temperatures have been previously shown to negatively impact posthatch growth in broiler chickens. The objective was to determine whether small incubation temperature variations owing to incubator tray location (LOC) could alter posthatch female and male broiler growth performance and carcass characteristics. Broiler hatching eggs were obtained from a 40-week-old commercial broiler breeder flock and incubated in trays placed in the bottom (BOT), middle (MID), and top (TOP) thirds of the racks (n = 4 racks per incubator tray LOC) in a single-stage incubator in a commercial hatchery. Chicks hatched from the 3 LOC (n = 720 per LOC) were vent sexed, vaccinated, and separate-sex reared with 12 birds per pen in a floor-pen facility and fed a common corn and soybean meal-based diet for 41 d. At day 41, all birds (n = 720) were processed to determine carcass and carcass part yields and incidence and severity of the meat quality defects wooden breast (WB) and white striping (WS). No LOC × Sex interactions were observed (P > 0.05). Growth performance and incidence and severity of WB and WS were similar among LOC (P > 0.05). However, broilers from BOT trays had heavier tender and breast weights than broilers from warmer MID trays (P < 0.05). Broilers from the BOT trays had higher breast meat yield as a proportion of carcass weight (25.00%) than warmer MID (24.54%) broilers (P < 0.05). However, broilers from warmer MID trays had greater carcass yield than those from cooler TOP trays (P < 0.05). As expected, male broilers had heavier carcass, breast, tender, wings, drumsticks and thighs weights and were more severely affected by WB than females (P < 0.05). Overall, these data indicate that the inherent differences in environmental factors among incubation LOC can impact broiler carcass and breast meat yields.


Assuntos
Galinhas/crescimento & desenvolvimento , Incubadoras/veterinária , Carne , Ração Animal/análise , Animais , Embrião de Galinha , Dieta , Feminino , Incubadoras/normas , Masculino , Carne/normas , Óvulo , Fatores Sexuais , Temperatura
2.
Poult Sci ; 100(1): 94-102, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33357712

RESUMO

Hatchery efficiency is based on hatchability and the number of salable chicks. The hatchery sector has been seeking new alternatives to optimize production rates, including the use of different systems (multistage [MS] or single-stage [SS] machines) to improve incubation conditions. The present study aimed to compare results for hatchability, chick quality, and broiler performance of chicks from 2 incubator systems-MS and SS. The experimental design for hatchability, hatch window, egg weight loss, and chick performance variables was completely randomized with 2 treatments (MS and SS). Performance variables were analyzed as a 2 x 2 factorial arrangement (incubator type x chick sex). Egg weight loss between incubation and transfer was higher for eggs incubated in MS (P < 0.05). Hatchability was higher for eggs incubated in SS (P < 0.05), and chicks in SS had a longer hatch window (P < 0.05). Embryo diagnosis revealed higher final mortality for embryos incubated in MS (P < 0.05), as well as higher percentages of alive and dead pipped and cracked eggs (P < 0.05). Physical quality was better for chicks from SS (P < 0.05). There was no interaction between the studied factors for performance results (P > 0.05). Incubator type did not affect broiler performance for any of the studied ages (P > 0.05), whereas male broilers had better performance than females (P < 0.05). The SS incubation system proved better than the MS system at meeting embryo requirements during embryo development, with better hatching rates and chick quality, although performance variables were not influenced by incubation type.


Assuntos
Criação de Animais Domésticos , Galinhas , Incubadoras , Zigoto , Criação de Animais Domésticos/instrumentação , Criação de Animais Domésticos/métodos , Animais , Embrião de Galinha/crescimento & desenvolvimento , Feminino , Incubadoras/normas , Incubadoras/veterinária , Masculino , Distribuição Aleatória , Fatores Sexuais , Zigoto/crescimento & desenvolvimento
3.
Reprod Biomed Online ; 40(1): 33-60, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31836437

RESUMO

This proceedings report presents the outcomes from an international expert meeting to establish consensus guidelines on IVF culture conditions. Topics reviewed and discussed were: embryo culture - basic principles and interactions; temperature in the IVF laboratory; humidity in culture; carbon dioxide control and medium pH; oxygen tension for embryo culture; workstations - design and engineering; incubators - maintaining the culture environment; micromanipulation - maintaining a steady physcochemical environment; handling practices; assessment practices; culture media - buffering and pH, general composition and protein supplementation, sequential or single-step media for human embryo culture; use and management - cold chain and storage; test equipment - calibration and certification; and laboratory equipment and real-time monitoring. More than 50 consensus guideline points were established under these general headings.


Assuntos
Meios de Cultura , Técnicas de Cultura Embrionária/normas , Fertilização in vitro/normas , Laboratórios/normas , Feminino , Humanos , Incubadoras/normas
4.
Ann Biol Clin (Paris) ; 77(5): 525-531, 2019 10 01.
Artigo em Francês | MEDLINE | ID: mdl-31512576

RESUMO

In order to perform biological analysis, clinical laboratories apply the instructions of reagent suppliers. For culture media these instructions are often incomplete and poorly adapted to the variety of clinical samples and micro-organisms. The REMIC can help to overcome these shortcomings. Required time of incubation for culture media are proposed based on the nature of the sample and the type of micro-organism suspected. Nevertheless, they are most often expressed in multiple of 24 hours and they are often considered as minimal by the laboratories. As the samples are inoculated "continuously", while the readings are most often done at a single definite time of the day, we propose a strategy to optimize incubation duration of cultures medium. A time of incubation in the day so-called "limit" is defined. From this, the incubations are stopped or prolonged according to the results of the culture and the direct examination. As the instructions of suppliers of culture media are not adapted, it appears necessary that these suppliers relies on the repositories of professional societies as this is the case for agars medias used for antibiotic susceptibility testing.


Assuntos
Serviços de Laboratório Clínico/normas , Meios de Cultura/normas , Técnicas Microbiológicas , Técnicas Bacteriológicas/métodos , Técnicas Bacteriológicas/normas , Calibragem , Humanos , Incubadoras/normas , Técnicas Microbiológicas/métodos , Técnicas Microbiológicas/normas , Fatores de Tempo
5.
J Assist Reprod Genet ; 36(8): 1571-1577, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31267335

RESUMO

PURPOSE: To investigate the stability of osmolality in non-humidified and humidified incubators for assisted reproductive technologies (ART). METHODS: Drops of three single-step culture media (media A, B, and C) were incubated for 5 or 6 days covered with four different mineral oils (oils A, B, C, and D) in non-humidified incubator A, non-humidified incubator B, or humidified incubator C to investigate the effects of incubator environment (humidification), drop volume, culture media, and mineral oil on the stability of osmolality in microdrops. RESULTS: A significant and linear increase was shown in the osmolality of 50-µL and 200-µL microdrops covered with mineral oil during 5 days incubation in non-humidified benchtop incubators. The maximum increase was 20 mOsm/kg, and the extent of the increase was affected by microdrop volume and possibly by the type of mineral oil used to cover the drops. In contrast, the osmolality of 50-µL and 200-µL microdrops did not change during 5 days incubation in a humidified benchtop incubator. CONCLUSIONS: Mineral oil alone may not adequately prevent gradual changes in the osmolality of low-volume microdrops during extended in vitro culture of human embryos in non-humidified incubators. As a result, the osmolality may increase to high enough levels to stress some human embryos and adversely affect clinical outcomes. We therefore recommend that the stability of osmolality should be given more consideration to ensure optimal culture conditions for ART.


Assuntos
Técnicas de Cultura Embrionária/instrumentação , Embrião de Mamíferos/citologia , Fertilização in vitro/normas , Umidade/normas , Incubadoras/normas , Meios de Cultura , Técnicas de Cultura Embrionária/métodos , Técnicas de Cultura Embrionária/normas , Desenvolvimento Embrionário , Feminino , Humanos , Óleo Mineral , Concentração Osmolar
6.
Reprod Biomed Online ; 39(1): 63-74, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31126717

RESUMO

RESEARCH QUESTION: Assisted reproduction laboratories record instrument performance periodically. No standardized guidelines have been produced for this activity despite mandatory auditing systems in several countries. This study of 36 laboratories in 12 different countries was conducted to assess differences and similarities between quality assurance programmes using an adaptable cloud-based quality-control app for instrument monitoring. DESIGN: A total of 36 deidentified IVF laboratories that subscribed to the same quality-assurance application were studied. Data were evaluated based on instrument types allocated to 10 domains: incubators, gas tanks, warming surfaces, refrigerators and freezers, cryo-storage, environment, water purification, peripheral equipment, checklists and miscellaneous. RESULTS: The incubator domain constituted the greatest proportion of parameters (35%), followed by surface warming instruments at 15%. Most incubator O2 readings were monitored between 4.5 and 5.5%, and between 5.5 and 6.5% for CO2. The altitude of the laboratory was poorly correlated with the CO2 setting. Incubator display and measured values of gases and temperature by built-in sensors vary considerably compared with third-party sensors. A quality-control diligence score or mean average data points was calculated for each laboratory. This score is independent of number of instruments or laboratory size. Higher scores were associated with laboratories in countries with government regulations and mandatory auditing systems. CONCLUSIONS: Major differences exist in instrument monitoring practices among laboratories. Although incubator monitoring is the largest domain, many other sensitive instruments are diligently monitored by most laboratories. International standardization and guidelines are needed.


Assuntos
Planejamento Ambiental , Laboratórios , Controle de Qualidade , Técnicas de Reprodução Assistida/instrumentação , Técnicas de Reprodução Assistida/normas , Planejamento Ambiental/normas , Análise de Falha de Equipamento , Feminino , Fertilização in vitro/instrumentação , Fertilização in vitro/normas , Humanos , Incubadoras/normas , Laboratórios/organização & administração , Laboratórios/normas , Ensaio de Proficiência Laboratorial/métodos , Masculino , Gravidez , Garantia da Qualidade dos Cuidados de Saúde/métodos , Garantia da Qualidade dos Cuidados de Saúde/normas , Refrigeração/instrumentação , Refrigeração/normas
7.
Semin Reprod Med ; 33(2): 103-17, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25734348

RESUMO

A large contributor to success during in vitro fertilization (IVF) lies in the processes occurring within the IVF laboratory. These processes make up the "culture system." This system entails numerous procedures and technical steps that must be optimized to produce a competent embryo. Notably, variations exist between programs that include differences in patient population, clinical stimulation, and other factors. Thus, a single "optimal" culture system to be utilized between all laboratories is likely not feasible. Rather, laboratory procedures should be optimized based on an individual laboratory's performance. That being said, within the scientific literature, there are key components, approaches, and techniques within the culture system that have been shown to be superior to alternatives. These key components important in improving embryo culture are discussed.


Assuntos
Blastocisto/fisiologia , Técnicas de Cultura Embrionária/normas , Fertilidade , Fertilização in vitro/normas , Infertilidade/terapia , Guias de Prática Clínica como Assunto/normas , Benchmarking/normas , Meios de Cultura/normas , Técnicas de Cultura Embrionária/instrumentação , Desenho de Equipamento , Feminino , Humanos , Incubadoras/normas , Infertilidade/diagnóstico , Infertilidade/fisiopatologia , Masculino , Gravidez , Taxa de Gravidez , Resultado do Tratamento
8.
Gynecol Endocrinol ; 30(10): 755-7, 2014 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-24948338

RESUMO

Two groups of egg recipients were treated, one in situ (165 patients; 195 cycles) and one after cross-border embryo transportation (340 cycles; 340 cycles) using mobile CO(2) incubator. The positive pregnancy rate per cycle was 199/340 (58.6%) and 99/195 (50.7%) in the transportation and the traveling group, respectively (NS). The clinical pregnancy rate (fetal heart beat) was 48.1 and 43.1% per embryo transfer cycle, respectively (NS) and the delivery rate was 44.1 and 35.9% per embryo transfer cycle, respectively (p = 0.01). Long distance transportation of human pre-implantation embryos using portable CO(2) incubator is safe and do not jeopardize their developmental potential.


Assuntos
Transferência Embrionária/instrumentação , Fertilização in vitro/normas , Incubadoras/normas , Doação de Oócitos/normas , Adulto , Dióxido de Carbono , Transferência Embrionária/normas , Feminino , Humanos , Gravidez , Adulto Jovem
9.
Reprod Biomed Online ; 28(5): 535-47, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24656561

RESUMO

Incubators in the IVF laboratory play a pivotal role in providing a stable and appropriate culture environment required for optimizing embryo development and clinical outcomes. With technological advances, several types of incubators are now available and careful consideration is required for selection. Examination of variables, such as recovery/stabilization of temperature, gas atmosphere and humidity, as well as understanding various approaches utilized by each device to regulate these variables, is critical. Additionally, a comprehensive examination of clinical studies that compare various incubators may provide insight into their efficacy. Other factors, both technical and practical, must also be considered when selecting an incubator. Importantly, proper management, including patient volume and workflow, is paramount in optimizing function of any incubator, regardless of the technology incorporated. This review highlights incubator function and reviews key environmental variables controlled and the technology utilized in various units. Additionally, existing comparative studies focused on incubator recovery and clinical outcomes are critically analysed. Finally, strategies employed for incubator management, as well as future potential incubator improvements are discussed. While existing reports indicate that smaller benchtop/topload incubators provide faster recovery of environmental variables, there is no clear advantage of any particular incubator based on clinical outcomes.


Assuntos
Técnicas de Cultura Embrionária/instrumentação , Fertilização in vitro/métodos , Fertilização in vitro/normas , Incubadoras/normas , Laboratórios , Poluição do Ar em Ambientes Fechados/análise , Tomada de Decisões , Técnicas de Cultura Embrionária/métodos , Técnicas de Cultura Embrionária/normas , Desenho de Equipamento , Gases/análise , Humanos , Laboratórios/organização & administração , Laboratórios/normas , Temperatura
10.
J Microbiol Methods ; 97: 29-33, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24361953

RESUMO

We describe the construction of temperature-light gradient incubator with a novel material: a thermally-conductive graphite foam that is lightweight, chemically resistant, economically competitive with metal, and much cheaper to fabricate. We combined this material with a variable-intensity LED light array to construct a low-cost light-temperature gradient incubator, and demonstrate its use for studies of microbial growth, enrichment, and isolation.


Assuntos
Incubadoras/normas , Luz , Microbiologia/instrumentação , Temperatura , Eucariotos/crescimento & desenvolvimento , Eucariotos/fisiologia , Grafite/química , Grafite/economia , Grafite/normas , Incubadoras/economia , Microbiologia/economia
11.
Animal ; 6(1): 137-44, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22436161

RESUMO

This study aimed to investigate whether suboptimal incubation (SI) temperature in weeks 1 and 3 of layer embryo incubation affects their development and post-hatch adaptive capacity during infectious challenges, by using Eimeria as a model infection under normal and immediately after more challenging environmental conditions of 72 h heat exposure. Eggs (n = 160 per treatment) were incubated at optimal (OI = 37.8°C continuously) or suboptimal eggshell temperature (36.7°C, 37.8°C and 38.9°C in weeks 1, 2 and 3, respectively). At day 33 of age, half the chickens of each incubation treatment were exposed to 72 h heat (35°C), whereas the other half remained under control conditions (21°C). At day 36 of age, all chickens were inoculated with 1 ml of a phosphate buffer saline solution containing 25 000 sporulated Eimeria acervulina oocysts/ml. The adaptive response to E. acervulina was measured by BW gain and FI from days 0 to 3 post infection (p.i.), days 3 to 5 p.i. and days 5 to 7 p.i., and by oocyst production (days 4 and 7 p.i.) and lesion scores in the duodenum (day 3, 4 and 7 p.i.). Our results demonstrated that SI temperatures in weeks 1 and 3 of incubation resulted in a reduction in yolk-free BW, chick length and navel condition. Moreover, SI temperature appeared to reduce the adaptive capacity to E. acervulina. This was demonstrated by tendencies to lower FI (P = 0.07) and BW gain (P = 0.08), more duodenal lesions (P = 0.09) and higher oocyst production (P = 0.02) after inoculation of E. acervulina. Higher lesion scores and faecal oocyst numbers were especially found when suboptimal incubation was combined with heat exposure preceding the infection. In conclusion, SI layer chickens tend to be less able to cope with an infectious challenge post hatch.


Assuntos
Galinhas/parasitologia , Coccidiose/veterinária , Eimeria/fisiologia , Incubadoras/normas , Doenças das Aves Domésticas/parasitologia , Temperatura , Adaptação Fisiológica , Bem-Estar do Animal , Animais , Embrião de Galinha/crescimento & desenvolvimento , Galinhas/crescimento & desenvolvimento , Coccidiose/parasitologia , Coccidiose/patologia , Duodeno/parasitologia , Duodeno/patologia , Feminino , Masculino , Doenças das Aves Domésticas/patologia , Distribuição Aleatória , Estresse Fisiológico
12.
Poult Sci ; 87(11): 2358-66, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18931188

RESUMO

For hatcheries, not only is it important to have a high level of hatchability, but the quality of the chicks provided also has to be good, because broiler farmers are looking for chicks with a high growth potential, resulting in a greater slaughter yield at the end of the rearing period. However, chick quality has proven to be a difficult and subjective matter to define. Therefore, the aim of this study was to investigate the predictive value of different chick quality measurements for BW at slaughter age. Body weight, chick length, shank length, and toe length measurements as well as Tona score determination were performed on 1-d-old chicks and were linked to posthatch performance parameters. Different breeder lines (Cobb and Ross) and breeder ages (39, 42, and 53 wk of age) were used to investigate line and age effects. In addition, variability between people and repeatability in time of these quality measurements were determined. Body weight at 7 d of age appeared to be the best predictor of BW at slaughter age among all the quality measurements performed. Body weight at 1 d of age had the second greatest predictive value, closely followed by the ratio between BW at 1 d of age and chick length squared. Chick length and shank length both had low to no predictive value whatsoever for posthatch performance. The lack of significant correlations between the Tona score and posthatch performance could be explained by the absence of day-old chicks with anomalies (and thus a suboptimal Tona score) because a distinction had already been made, as is done in practice, between top-grade and lower grade chicks.


Assuntos
Galinhas/crescimento & desenvolvimento , Incubadoras/normas , Animais , Animais Recém-Nascidos , Tamanho Corporal , Peso Corporal , Cruzamento/normas , Embrião de Galinha/fisiologia , Reprodutibilidade dos Testes
13.
Fertil Steril ; 89(3): 703-10, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17524397

RESUMO

OBJECTIVE: To study the effect of incubator management on assisted reproductive technology (ART) outcomes. DESIGN: Series of retrospective and controlled, randomized studies. SETTING: Tertiary care infertility practice. PATIENT(S): Mammalian gametes/embryos. INTERVENTION(S): Evaluation of human and bovine oocytes/embryos cultured in various environmental conditions. MAIN OUTCOME MEASURE(S): Fertilization and embryo development rate as well as clinical pregnancy rate (PR). CONCLUSION(S): Here we review the general topic of incubator management as it pertains to ART. Discussed within the context of this article will be our experiences as they relate to incubator management. Details as they apply to incubator environment also will include gamete/embryo positions within incubator, air quality, and quality control.


Assuntos
Técnicas de Cultura Embrionária/instrumentação , Ambiente Controlado , Fertilização in vitro/instrumentação , Incubadoras , Laboratórios Hospitalares , Oócitos , Técnicas de Reprodução Assistida/instrumentação , Técnicas de Cultura de Tecidos/instrumentação , Adulto , Animais , Dióxido de Carbono/metabolismo , Bovinos , Técnicas de Cultura Embrionária/normas , Desenho de Equipamento , Feminino , Filtração/instrumentação , Humanos , Concentração de Íons de Hidrogênio , Incubadoras/normas , Laboratórios Hospitalares/normas , Teste de Materiais , Oócitos/metabolismo , Oxigênio/metabolismo , Gravidez , Taxa de Gravidez , Controle de Qualidade , Técnicas de Reprodução Assistida/normas , Estudos Retrospectivos , Temperatura , Técnicas de Cultura de Tecidos/normas
14.
Artigo em Inglês | MEDLINE | ID: mdl-17050931

RESUMO

BACKGROUND: Toxic epidermal necrolysis can be fatal and nursing care with careful monitoring of temperature and humidity can improve survival rate. We adapted the greenhouse and igloo principle using a common hood to monitor the temperature and humidity. METHODS: A small heater with a regulator was placed in a mini hood and temperature was recorded inside the uncovered hood and hood covered with green cloth and aluminium foil separately. The regular hood was placed over a volunteer and the temperature was measured inside the open hood and hood covered with green cloth and aluminium foil separately. The relative humidity was also monitored using Zeal mercury dry--wet bulb hygrometer. RESULTS: Temperature increase was most marked in the foil-covered hood followed by cloth-covered hood, both with the heater and the volunteer. Similarly, in the volunteer study, the humidity was best maintained inside the aluminium foil-covered hood. CONCLUSION: We recommend the use of regular hood with suitable cover to monitor the humidity and temperature of patients with toxic epidermal necrolysis.


Assuntos
Calefação/métodos , Umidade , Temperatura , Temperatura Corporal/fisiologia , Regulação da Temperatura Corporal/fisiologia , Efeito Estufa , Calefação/instrumentação , Humanos , Umidade/normas , Incubadoras/normas , Masculino , Síndrome de Stevens-Johnson/terapia
15.
J Assist Reprod Genet ; 19(8): 368-75, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12182443

RESUMO

PURPOSE: To assess the ability of various facets of embryo culture (microscope stage warmers, volumes of culture media, culture vessel lids, and type of culture incubator) to maintain a constant temperature in vitro. METHODS: Ability to maintain 37.0 degrees C in the microenvironment of gametes was recorded by digital thermocouple in the chosen facets of in vitro culture. RESULTS: Stage warmers are highly variable in their ability to maintain the set temperature (range 33.8 degrees C-37.0 degrees C after 60 s). Temperature loss in culture media is both volume and vessel dependent, and the direct heat transfer culture incubator (MINC) has superior temperature maintenance compared with a large volume air convection incubator (FORMA), where temperature regain from 35.0 degrees C to 37.0 degrees C took 5.5 min compared to >20 min. CONCLUSIONS: There are large measurable differences in the ability to maintain set temperature that depend on the stage warmer used, volume of media, use of vessel lids, and the type of incubator chosen for IVF culture.


Assuntos
Técnicas de Cultura de Células/métodos , Desenvolvimento Embrionário e Fetal/fisiologia , Técnicas de Reprodução Assistida/instrumentação , Técnicas de Cultura de Células/instrumentação , Feminino , Humanos , Incubadoras/normas , Masculino , Temperatura
16.
Bioelectrochemistry ; 53(1): 119-25, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11206919

RESUMO

Biofilm are formed wherever there is some water in our environment: pipes, pipelines, tap water systems, air conditioning systems... Furthermore, the ecological and economical consequences are very important: energy losses, bacterial contamination, material deterioration. The aim of this work is to develop a new method to detect and monitor the biofilm formation. This method can also determine some mechanical properties of the biofilm. An application of this method is a realization of a biofilm sensor. Biofilm is considered as an inert porous layer with respect to mass transport. In our experiment, the biofilm is grown on a gold electrode in natural seawater. Its thickness is determined by considering the oxygen diffusion limiting current measured for different rotation speeds on this electrode. Two different incubators are used during the biofilm development: one, with a laminar flow, permits the rotation of the electrode during the biofilm formation, and for the second, a tube is used under turbulent conditions during the biofilm formation. This experiment allows us to characterize the mechanical behavior (thickness, elasticity, rigidity) of the biofilm in function of different conditions of development.


Assuntos
Biofilmes/crescimento & desenvolvimento , Fenômenos Biomecânicos , Elasticidade , Eletrodos , Desenho de Equipamento , Ouro , Incubadoras/microbiologia , Incubadoras/normas , Modelos Químicos , Oxigênio , Rotação , Água do Mar/microbiologia , Fatores de Tempo
17.
Braz. j. microbiol ; 31(2): 83-6, Apr.-Jun. 2000. ilus, tab, graf
Artigo em Inglês | LILACS | ID: lil-297641

RESUMO

Parameters for a more effcient biotransformation of diterpene-like compounds by the fungus "Cephalosporium aphidicola" were established by carrying out microscale feeding at several conditions. Experiments were guided by thin layer chromatography and gas chromatography analysis. It was observed that the substrate should be added in ethanol at concentrations between 15 to 14 mg per 100 ml of medium. The extraction of the product showed to be more effcient when carried out from both mycelia and broth and using ethylacetate as the extracting solvent. The experiment should be stopped six days after feeding the substrate to the fungus for the best product yield.


Assuntos
Acremonium/enzimologia , Biotransformação , Diterpenos/química , Técnicas In Vitro , Cromatografia Gasosa , Cromatografia em Camada Fina , Incubadoras/normas
18.
Santiago de Chile; s.n; 2000. 87 p. ilus, tab, graf.
Tese em Espanhol | LILACS | ID: lil-284676

RESUMO

Se realizó un estudio sobre el uso de nidos y cubreincubadoras en recién nacidos prematuros que pesaron menos de 1500 grs, hospitalizados en la sala de Cuidados Integrales del Prematuro (UCIPrem) de la Unidad de Neonatología del Hospital Dr. Sótero del Río, con el fín de evaluar el incremento de peso y regulación de temperatura. El nido consiste en un pequeño saco; la cubreincubadora es una cubierta de tela que se coloca sobre la cúpula de la incubadora para simular el ambiente intrauterino. La investigación fue de tipo analítico, retroprospectivo, de casos y controles. Se estudiaron dos grupos, con un n=16 para cada uno. Ambos grupos tenían menos de 15 días de edad cronológica y no presentaban patologías que comprometieran las variables en estudio. Los niños que integraron el grupo de casos se estudiaron entre los meses de junio de 1998 y mayo de 1999, el grupo control entre los meses de junio de 1997 y mayo de 1998. En los resultados se evidenció que ambos grupos, hasta la tercera semana, regulaban temperatura según su ambiente térmico neutro, en ellos el incremento de peso y regulación de temperatura eran muy similares. Sin embargo, en la cuarta semana los niños que usaron nidos y cubreincubadoras, necesitaron un grado menos de temperatura de incubadora que el ambiente térmico neutro esperado para su peso y edad cronológica y aumentaban en promedio 59,2 grs. más que el grupo control


Assuntos
Recém-Nascido , Humanos , Masculino , Feminino , Incubadoras/normas , Recém-Nascido Prematuro/fisiologia , Regulação da Temperatura Corporal/fisiologia , Hospitalização/estatística & dados numéricos , Recém-Nascido de muito Baixo Peso , Aumento de Peso/fisiologia
19.
Poult Sci ; 76(1): 124-33, 1997 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-9037699

RESUMO

A simple model to describe the relationship between the temperature of the developing embryo, incubator temperature, embryo heat production, and thermal conductivity of the egg and surrounding air is presented. During early incubation, embryo temperature is slightly lower than incubator temperature because of evaporative cooling. However, from midincubation onwards, metabolic heat production from the embryo raises embryo temperature above incubator temperature. The extent of the rise in embryo temperature depends on thermal conductivity, which, in turn, is mainly influenced by the air speed over the egg. The importance of air speed and restrictions to air flow within artificial incubators is discussed. Exact determinations of optimum incubation temperatures from studies reported in the literature are difficult because only incubator temperatures are reported. Embryo temperatures can differ from incubator temperature because of differences in thermal conductivity between different incubation systems and differences between incubators in their ability to control temperatures uniformly. It is suggested that shell surface temperatures are monitored in experiments to investigate temperature effects to allow consistent comparisons between trials. Monitoring shell temperatures would also make it easier to translate optimum temperatures derived in small experimental incubators to the large commercial incubators used by the poultry industry. The relationship between egg temperature, the metabolism of the developing embryo and egg size is discussed.


Assuntos
Embrião de Galinha/fisiologia , Ovos/normas , Desenho de Equipamento , Incubadoras/normas , Modelos Biológicos , Temperatura , Animais , Regulação da Temperatura Corporal/fisiologia , Embrião de Galinha/metabolismo , Galinhas , Casca de Ovo/fisiologia , Condutividade Térmica
20.
Br Poult Sci ; 36(1): 51-65, 1995 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7614026

RESUMO

1. A batch of 320 ostrich eggs from 9 different farms in Zimbabwe were incubated in a single stage operation and the fate of each was recorded. 2. Hatchability was only 37.2% and the result of high rates of infertility and contamination (22.2% and 22.8% respectively); it varied between eggs from different farms. 3. Embryonic mortality was high at the start and end of incubation, a pattern similar to that of other domestic birds. 4. Mortality of late stage embryos was related to percentage water loss and mass specific water vapour conductance of the shell, with extremes of the ranges causing the highest mortality. 5. Microbial contamination of the eggs was a significant problem and varied in eggs from different farms indicating that more attention is needed in both breeder bird and nest management.


Assuntos
Desenvolvimento Embrionário , Incubadoras/veterinária , Aves Domésticas/embriologia , Animais , Embrião não Mamífero/microbiologia , Incubadoras/normas , Infertilidade/veterinária , Óvulo/crescimento & desenvolvimento , Óvulo/microbiologia
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