scholarly journals Diversidad ecológica de aves en un hábitat fragmentado en la comunidad de Rincón Largo, Chiriquí, Panamá

2020 ◽  
Vol 22 (1) ◽  
Author(s):  
Karol Madeline Gutiérrez Pineda ◽  
Pedro G. Méndez-Carvajal
Keyword(s):  
Ad Libitum ◽  
Educación Científica

Los estudios de diversidad ecológica son esenciales para promover planes de educación científica-ambiental y conservación. Estudios previos de biodiversidad se han realizado en tierras altas para la provincia de Chiriquí, pero pocos para tierras bajas. El objetivo fue evaluar la diversidad ecológica de aves en la comunidad de Rincón Largo, un paisaje fragmentado con actividad antropogénica ubicado en tierras bajas de la provincia. Se considero el uso de suelo para categorizar tres áreas de observación: A1 (calles principales y aledañas), A2 (cercas vivas, pastizales y bosques de galería), A3 (laguna artificial). Utilizamos métodos de observación Ad-libitum, transecto de franja y poste de observación. Las observaciones las realizamos de enero a diciembre de 2018, con esfuerzo de muestreo total de 1,920 hrs. Detectamos 469 individuos en 91 especies, 33 familias, 15 órdenes. Los índices de Diversidad alpha muestran que existe alta diversidad, abundancia y riqueza, con equitatividad en las familias. Las tres áreas de observación no presentan diferencia significativa en la diversidad alpha, H = 5.6, P = 0.06, aunque marginal. Estos resultados describen por primera vez la avifauna de Rincón Largo y muestran la capacidad de retención de biodiversidad original en zonas fragmentadas con base en corredores biológicos como cercas vivas, bosques de galería y árboles frutales, crucial en conservación.

Light and electron microscopic investigation of adenohypophyses of germfree, food-restricted, and germfree-food restricted aging, male lobund-wistar rats

1988 ◽  
Vol 46 ◽  
pp. 352-353
Author(s):  
G. Ilse ◽  
K. Kovacs ◽  
N. Ryan ◽  
T. Sano ◽  
L. Stefaneanu ◽  
...  
Keyword(s):  
Wistar Rats ◽  
Microscopic Investigation ◽  
Electron Microscopic Investigation ◽  
Aging Male ◽  
Sprague Dawley ◽  
Electron Microscopic ◽  
Sprague Dawley Rats ◽  
Old Rats ◽  
Ad Libitum ◽  
Microscopic Findings

Germfree state and food restriction have been shown to increase life span and delay tumor occurrence in rats. We report here the histologic, immunocytochemical and electron microscopic findings of adenohypophyses of aging, male Lobund-Wistar rats raised at Lobund Laboratories. In our previous study, the morphologic changes in the adenohypophyses of old rats have been extensively investigated by histology, immunocytochemistry and electron microscopy. Lactotroph adenomas were frequent in Long-Evans and Sprague-Dawley rats, whereas gonadotroph adenomas were frequent in Sprague-Dawley and Wistar rats.Male Lobund-Wistar rats were divided into four groups: 1) conventional, which were raised under normal non-germfree environment and received food ad libitum; 2) germfree-food ad libitum; 3) conventional environment-food restricted and 4) germfree-food restricted. The adenohypophyses were removed from 6-month-, 18-month- and 30-month-old rats. For light microscopy, adenohypophyses were fixed in formalin and embedded in paraffin.

Alteration of Mitochondria in Oxythiamine-Induced, Acute Thiamine Deficiency in the Mouse

1976 ◽  
Vol 34 ◽  
pp. 284-285
Author(s):  
Itaru Watanabe ◽  
Dante G. Scarpelli
Keyword(s):  
Electron Microscopy ◽  
Adult Male ◽  
Thiamine Deficiency ◽  
Light And Electron Microscopy ◽  
Fatty Change ◽  
Deficient Diet ◽  
Subcutaneous Injections ◽  
Swiss Mice ◽  
Time Period ◽  
Ad Libitum

Acute thiamine deficiency was produced in mice by the administration of oxythiamine, a thiamine analogue, superimposed upon a thiamine deficient diet. Adult male Swiss mice (30 gm. B.W.) were fed with a thiamine deficient diet ad libitumand were injected with oxythiamine (170 mg/Kg B.W.) subcutaneously on days 4 and 10. On day 11, severe lassitude and anorexia developed, followed by death within 48 hours. The animals treated daily with subcutaneous injections of thiamine (300 μg/Kg B.W.) from day 11 through 15 were kept alive. Similarly, feeding with a diet containing thiamine (600 μg/Kg B.W./day) from day 9 through 17 reversed the condition. During this time period, no fatal illness occurred in the controls which were pair-fed with a thiamine deficient diet.The oxythiamine-treated mice showed a significant enlargement of the liver, which weighed approximately 1.5 times as much as that of the pair-fed controls. By light and electron microscopy, the hepatocytes were markedly swollen due to severe fatty change and swelling of the mitochondria.

Aprendizaje ecológicamente basado en casos

2020 ◽  
Vol 11 (21) ◽  
Author(s):  
Isabel López Zamora
Keyword(s):  
Educación Científica

Los estudios de caso se han utilizado en la educación científica como una forma para desarrollar en los estudiantes las habilidades de pensamiento crítico y para la resolución de problemas complejos. Sin embargo, existe poca documentación respecto a si este método de enseñanza está teniendo el impacto deseado en los estudiantes, específicamente los que atienden cursos de ecología vegetal. Para evaluar la posible influencia de la utilización de casos en la enseñanza de la ecología de la invasión, el presente estudio integró algunas estrategias docentes interactivas, tal y como: 1) el aprendizaje basado en casos, 2) la educación basada en campo y 3) la vinculación de la investigación con la educación durante su impartición. Los estudiantes abordaron sesiones de tópicos ecológicos diversos y concluyeron actividades indagatorias y estudios de caso sobre plantas invasoras en escenarios de campo locales para un real y avanzado entendimiento de la ecología de la invasión y ayudar a que desarrollaran sus habilidades de pensamiento, a la par de que pudieran relacionarse e interactuar con su entorno inmediato. Los métodos de evaluación para el desempeño de los alumnos estuvieron enfocados en la activa participación y efectiva ejecución de las actividades, ejercicios breves, y colaboración de pares en los estudios de caso, y en la intervención como evaluadores de cada sesión, del trabajo de campo y de los aspectos generales del curso. Los resultados de este estudio indican que los estudiantes mostraron una actitud abierta para el aprendizaje basado en casos, y que este método de enseñanza les ayudó a desarrollar la habilidad de pensamiento requerida para diagnosticar y resolver problemas reales de invasión a nivel local, al mismo tiempo que los conectó con el resto del contenido del curso.

Dissociable hormonal responses to symptoms and stress in anorexia and bulimia nervosa

2019 ◽  
Author(s):  
Margaret L Westwater ◽  
Flavia Mancini ◽  
Jane Shapleske ◽  
Jaco Serfontein ◽  
Monique Ernst ◽  
...  
Keyword(s):  
Bulimia Nervosa ◽  
Acute Stress ◽  
Gut Hormones ◽  
Metabolic Dysfunction ◽  
Cortisol Reactivity ◽  
Psychological States ◽  
Study Session ◽  
Gut Hormone ◽  
Ad Libitum ◽  
Acyl Ghrelin

Background: Anorexia nervosa (AN) and bulimia nervosa (BN) are complex psychiatric conditions, in which both psychological and metabolic factors have been implicated. Critically, the experience of stress can precipitate loss-of-control eating in both conditions, suggesting an interplay between mental state and metabolic signaling. However, associations between psychological states, symptoms and metabolic processes in AN and BN have not been examined. Methods: Eighty-five women (n=22 AN binge/purge subtype, n=33 BN, n=30 controls) underwent remote salivary cortisol sampling and a two-day, inpatient study session to examine the effect of stress on cortisol, gut hormones (acyl-ghrelin, PYY, GLP-1) and food consumption. Participants were randomized to either an acute stress induction or control task on each day, and plasma hormones were serially measured before a naturalistic, ad libitum meal.Results: Cortisol awakening response (CAR) was augmented in AN but not BN relative to controls, with body mass index explaining the most variance in CAR (36%). Acute stress increased acyl-ghrelin and PYY in AN compared to controls; however, stress did not alter gut hormone profiles in BN. Instead, a group-by-stress interaction showed nominally reduced cortisol reactivity in BN, but not AN, compared to controls. Ad libitum consumption was lower in both patient groups and unaffected by stress.Conclusions: Findings extend previous reports of metabolic dysfunction in binge-eating disorders, identifying unique associations across disorders and under stress. Moreover, we observed disrupted homeostatic signaling in AN following psychological stress, which may explain, in part, the maintenance of dysregulated eating in this serious illness.

AVALIAÇÃO DO EFEITO HIPOGLICEMIANTE DA FARINHA DE BANANA VERDE E DO KOMBUCHA EM RATOS WISTAR ALIMENTADOS COM DIETA DE CAFETERIA HIPERGLICÍDICA

2019 ◽  
pp. 32-33
Author(s):  
Marianela Andrea Díaz Urrutia ◽  
Amanda Ramos ◽  
Rafaela Menegusso ◽  
Rafael Dewes ◽  
Sóstenez Alexandre Silva ◽  
...  
Keyword(s):  
Dieta De Cafetería ◽  
Ad Libitum

Introdução: Na atualidade, os hábitos alimentares da população do Brasil e do mundo, se caracterizam por um excessivo consumo de alimentos ricos em açúcares simples, gorduras saturadas e sal. O Diabetes Melito é uma doença crônica não transmissível que se desencadeia, muitas vezes, como consequência de uma alimentação inadequada. Este distúrbio metabólico, gera quadros de hiperglicemia e a terapia nutricional é fundamental no tratamento. Objetivo: O trabalho teve o objetivo de avaliar a ação hipoglicemiante do kombucha como probiótico, farinha de banana verde (FBV) como prebiótico e a associação destes alimentos como simbiótico em uma dieta de cafeteria com alto teor de açúcares oferecida a ratos wistar. Métodos: Para este experimento foram utilizados 35 ratos wistar machos e sadios, recém desmamados com 21 dias de vida, que foram distribuídos em 5 grupos de 7 animais, sendo eles: Grupo 1: dieta ração comercial (controle), Grupo 2: dieta de cafeteria, Grupo 3: dieta de cafeteria + kombucha, Grupo 4: dieta de cafeteria + FBV, Grupo 5: dieta de cafeteria + FBV + kombucha. O ensaio teve uma duração total de 55 dias, onde os primeiros 10 dias foram para induzir o diabetes nos animais dos grupos 2, 3, 4 e 5, mediante a dieta de cafeteria com alto teor de açúcares simples. Posteriormente, começou o período experimental, que teve uma duração de 45 dias, onde o kombucha e solução salina foram administrados por gavagem, com uma dose referente a 5mL/kg de peso do animal. Durante todo o experimento, os animais receberam água e ração ad libitum. Após a eutanásia dos animais, foram coletadas amostras de sangue para análises de glicemia e amilase pancreática mediante turbidimetria. Resultados: Como resultado, foram obtidos os seguintes valores para a glicemia e amilase pancreática de cada grupo: 65,86±11,60 mg/dL e 23,57±4,20 U/L para o Grupo 1; 104,14±114,92 mg/dL e 25,0±14,85 U/L para o Grupo 2; 49,00±13,18 mg/dL e 35,0±15,72 U/L para o Grupo 3; 73,86±24,78 mg/dL e 128,14±50,03 U/L para o Grupo 4; 72,29±33,87 mg/dL e 274,14±105,27 U/L para o Grupo 5, respectivamente. Conclusão: Observando os resultados da glicemia do grupo 1, onde não houve suplementação funcional, verifica-se que a dieta de cafeteria com alto teor de açúcares simples, foi eficaz na indução do diabetes. Ainda analisando os resultados da glicemia, é possível confirmar, que a suplementação isolada, tanto do probiótico kombucha como do prebiótico FBV, apresentam função hipoglicemiante, porém o efeito do prebiótico, é menos eficaz que o efeito do probiótico. Por outro lado, observou-se que, perante a associação simbiótica destes alimentos, o kombucha parece potencializar o efeito redutor da glicemia da FBV. Enquanto aos resultados da concentração de amilase no sangue dos animais, constatou-se que a suplementação isolada de FBV estimulou, consideravelmente, a secreção do referido hormônio e que o kombucha inibiu essa ação estimulante do prebiótico no grupo 5, onde houve associação de ambos sumplementos.

The Effect of Feeding System on the Carcass Quality of Crossbred Lambs with Texel

2020 ◽  
Vol 68 (1) ◽  
pp. 17-24
Author(s):  
Angela Cividini ◽  
Dušan Terčič ◽  
Mojca Simčič
Keyword(s):  
Growth Rate ◽  
Meat Quality ◽  
Carcass Quality ◽  
Quality Traits ◽  
Feeding System ◽  
Ad Libitum ◽  
Daily Gain ◽  
Effect Of Feeding ◽  
Carcass Cuts

The aim of this study was to estimate the effect of feeding system on the growth rate and carcass quality of crossbred Improved Jezersko-Solčava x Texel (JSRT) lambs and to evaluate the effect of sex on these traits. The trial was conducted in nature according to the traditional rearing systems. The trial included 44 crossbred lambs, which were born and reared until the slaughter in three different flocks. In the age of 10 days suckled lambs were offered with ad libitum corresponding diets according to the feeding system. All lambs were slaughtered in seven consecutive days by the same procedure. The effect of feeding system significantly affected daily gain from birth to slaughter, EUROP carcass conformation and shoulder width. Likewise, the effect of sex significantly affected daily gain from birth to slaughter and internal fatness of carcasses. According to carcass cuts the feeding system significantly affected only the proportion of neck and leg. Considering meat quality traits, feeding system had a significant effect on the pH 45 and CIE a* values. In this study, we could speculate that more than the feeding system the growth and the carcass traits as well as meat traits were affected by the amount of the supplement.

Effect of Offering Concentrate Rations with Different Energy Densities on Calf Performance

1993 ◽  
Vol 1993 ◽  
pp. 209-209 ◽  
Author(s):  
R.J. Fallon ◽  
J.R. Twigge
Keyword(s):  
Energy Density ◽  
Rapid Growth ◽  
High Energy ◽  
Solid Food ◽  
Milk Replacer ◽  
Successful Transition ◽  
Calf Performance ◽  
Ad Libitum

The primary aim of the calf rearer is to ensure a successful transition from non ruminant to ruminant status while achieving rapid growth and an early intake of solid food. Newbold, Blake and Hagges (1991), found that increasing the concentration of ME in either the starter or milk replacer will not promote more rapid growth, but will simply reduce the rate of starter consumption. This present study investigated the extent to which the energy density of a calf starter ration affected starter intake and liveweight gain in calves receiving a fixed allowance of a high energy milk replacer with ad libitum access to solid calf starter rations.

scholarly journals PSIX-6 Gastrointestinal microbiome of calves fed solid diets containing different levels and sources of NDF

2020 ◽  
Vol 98 (Supplement_4) ◽  
pp. 418-419
Author(s):  
Gercino F Virgínio Júnior ◽  
Milaine Poczynek ◽  
Ana Paula Silva ◽  
Ariany Toledo ◽  
Amanda Cezar ◽  
...  
Keyword(s):  
Illumina Miseq ◽  
Diversity Indices ◽  
Dairy Calves ◽  
Rrna Gene ◽  
Gastrointestinal Microbiome ◽  
Fecal Microbiome ◽  
Miseq Platform ◽  
Holstein Calves ◽  
Ad Libitum ◽  
Different Levels

Abstract Different levels and sources of NDF can modify the gastrointestinal microbiome. This study evaluated 18 Holstein calves housed in not-bedded suspended individual cages and fed one of three treatments: 22NDF - conventional starter containing 22% NDF (n = 7); 31NDF - starter with 31% NDF, replacing part of the corn by soybean hull (n = 6); and 22NDF+H - conventional starter with 22% NDF plus coast-cross hay ad libitum (n = 5). All animals received 4 L of milk replacer daily (24% CP; 18.5% fat; diluted to 12.5% solids), divided into two meals, being weaned at 8th week of age. After weaning, animals were housed in tropical shelters, fed with the respective solid diet and coast-cross hay ad libitum for all treatments. To evaluate the microbiome, ruminal fluid samples were collected using a modified Geishauser oral probe at weeks 2, 4, 6, 8 and 10, two hours after the morning feeding, and fecal samples were collected at birth (0) and at weeks 1, 2, 4, 8 and 10. The microbial community was determined by sequencing V3 and V4 region amplicons of the 16S rRNA gene that was amplified by PCR and sequenced by the Illumina MiSeq platform. Ruminal microbiome had no differences in diversity for the effects of weeks, treatments or interaction of both factors (Table 1). In feces, the diversity indices and evenness were higher for 22NDF+H when compared to 22NDF, with no difference for 31NDF. All indices were significantly affected by calves age. At birth, calves had the greatest diversity and richness. Week 1 and 2 had less evenness and diversity. Bacteroidota, Firmicutes_A and Firmicutes_C were the most abundant phylum in rumen and feces. The supply of hay was only effective in modifying the fecal microbiome of dairy calves, suggesting a resilience in the ruminal microbiome.

Sign in / Sign up

Export Citation Format

Share Document