Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 55
Filtrar
1.
Sci Rep ; 11(1): 7113, 2021 03 29.
Artículo en Inglés | MEDLINE | ID: mdl-33782490

RESUMEN

Eosinophilic esophagitis (EoE) is a chronic, immune-mediated inflammatory esophageal disease triggered by food antigens. Cumulative evidence supports the implication of microbiota and the innate immune system in the pathogenesis of EoE. Changes in the esophageal microbiome were investigated by applying 16S rRNA gene sequencing on esophageal biopsies of adult patients with active EoE at baseline (n = 30), and after achieving remission with either proton pump inhibitors (PPI, n = 10), swallowed topical corticosteroids (STC, n = 10) or food-elimination diets (FED, n = 10). Ten non-EoE biopsies were also characterized as controls. Compared to controls, no differences in alpha (intra-sample) diversity were found in EoE microbiota overall. However, it decreased significantly among patients who underwent FED. As for beta (inter-sample) diversity, non-EoE controls separated from EoE baseline samples. Post-treatment samples from patients treated with PPI and FED had a more similar microbiota composition, while those receiving STC were closer to controls. Differential testing of microbial relative abundance displayed significant changes for Filifactor, Parvimonas and Porphyromonas genera. Analysis of predicted functions indicated alterations in metabolic pathways and abundance of sulphur-cytochrome oxidoreductases. Our findings demonstrate changes in microbiota associated with EoE, as well as a treatment effect on the microbiome.


Asunto(s)
Dieta , Esofagitis Eosinofílica/microbiología , Esofagitis Eosinofílica/terapia , Esófago/microbiología , Microbiota , Corticoesteroides/uso terapéutico , Esofagitis Eosinofílica/dietoterapia , Esofagitis Eosinofílica/tratamiento farmacológico , Humanos , Inhibidores de la Bomba de Protones/uso terapéutico , ARN Ribosómico 16S/genética
2.
Health Policy ; 122(8): 900-907, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-29935730

RESUMEN

The Triple Aim framework is an increasingly popular tool for designing and assessing quality improvements in the health care sector. We systematically reviewed the empirical evidence on the application of the Triple Aim framework within primary healthcare settings since its inception almost a decade ago. Results show that primary healthcare providers varied in their interpretation of the Triple Aim framework and generally struggled with a lack of guidance and an absence of composite sets of measures for performance assessment. Greater clarity around application of the Triple Aim framework in primary healthcare is needed, especially around the selection and implementation of purposeful measures from locally available data. This review highlights areas for improvement and makes recommendations intended to guide future applications of the Triple Aim in the context of primary healthcare.


Asunto(s)
Reforma de la Atención de Salud/organización & administración , Innovación Organizacional , Atención Primaria de Salud/organización & administración , Mejoramiento de la Calidad/organización & administración , Control de Costos , Política de Salud , Humanos , Evaluación de Procesos y Resultados en Atención de Salud , Atención Primaria de Salud/normas
3.
Aging Ment Health ; 22(8): 990-998, 2018 08.
Artículo en Inglés | MEDLINE | ID: mdl-28541798

RESUMEN

OBJECTIVES: To identify feasible models of intergenerational care programmes, that is, care of children and older people in a shared setting, to determine consumer preferences and willingness to pay. METHOD: Feasible models were constructed in extensive consultations with a panel of experts using a Delphi technique (n = 23) and were considered based on their practical implementation within an Australian setting. This informed a survey tool that captured the preferences and willingness to pay for these models by potential consumers, when compared to the status quo. Information collected from the surveys (n = 816) was analysed using regression analysis to identify fundamental drivers of preferences and the prices consumers were willing to pay for intergenerational care programmes. RESULTS: The shared campus and visiting models were identified as feasible intergenerational care models. Key attributes of these models included respite day care; a common educational pedagogy across generations; screening; monitoring; and evaluation of participant outcomes. Although parents were more likely to take up intergenerational care compared to the status quo, adult carers reported a higher willingness to pay for these services. Educational attainment also influenced the likely uptake of intergenerational care. CONCLUSIONS: The results of this study show that there is demand for the shared campus and the visiting campus models among the Australian community. The findings support moves towards consumer-centric models of care, in line with national and international best practice. This consumer-centric approach is encapsulated in the intergenerational care model and enables greater choice of care to match different consumer demands.


Asunto(s)
Cuidado del Niño/organización & administración , Disfunción Cognitiva/rehabilitación , Comportamiento del Consumidor , Centros de Día/organización & administración , Modelos Organizacionales , Cuidados Intermitentes/organización & administración , Adulto , Anciano , Australia , Niño , Técnica Delphi , Encuestas de Atención de la Salud , Humanos , Apoyo Social
4.
Gene Ther ; 24(10): 640-648, 2017 10.
Artículo en Inglés | MEDLINE | ID: mdl-28771235

RESUMEN

Characterization of adeno-associated viral vector (AAV) mediated gene delivery to the enteric nervous system (ENS) was recently described in mice and rats. In these proof-of-concept experiments, we show that intravenous injections of clinically relevant AAVs can transduce the ENS in guinea pigs and non-human primates. Neonatal guinea pigs were given intravenous injections of either AAV8 or AAV9 vectors that contained a green fluorescent protein (GFP) expression cassette or phosphate-buffered saline. Piglets were euthanized three weeks post injection and tissues were harvested for immunofluorescent analysis. GFP expression was detected in myenteric and submucosal neurons along the length of the gastrointestinal tract in AAV8 injected guinea pigs. GFP-positive neurons were found in dorsal motor nucleus of the vagus and dorsal root ganglia. Less transduction occurred in AAV9-treated tissues. Gastrointestinal tissues were analyzed from young cynomolgus macaques that received systemic injection of AAV9 GFP. GFP expression was detected in myenteric neurons of the stomach, small and large intestine. These data demonstrate that ENS gene delivery translates to larger species. This work develops tools for the field of neurogastroenterology to explore gut physiology and anatomy using emerging technologies such as optogenetics and gene editing. It also provides a basis to develop novel therapies for chronic gut disorders.


Asunto(s)
Dependovirus/genética , Sistema Nervioso Entérico/metabolismo , Técnicas de Transferencia de Gen , Terapia Genética/métodos , Animales , Femenino , Ganglios Espinales/citología , Ganglios Espinales/metabolismo , Vectores Genéticos/genética , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Cobayas , Inyecciones Intravenosas , Macaca fascicularis , Masculino , Neuronas/metabolismo , Nervio Vago/metabolismo
5.
Stud Health Technol Inform ; 168: 35-43, 2011.
Artículo en Inglés | MEDLINE | ID: mdl-21893909

RESUMEN

This paper describes a case study involving third-year undergraduate computing students and their conduct of a patient journey modeling project for the Ambulatory Care department of a Regional Hospital in New South Wales, Australia. The goal of the research was to determine if students, given minimal training in an emerging patient journey modeling tool known as Essomenic, could be an effective vehicle for the diffusion of innovation to operational staff involved in a healthcare improvement project. Under academic supervision, students interacted directly with staff to develop models of the current system of care from GP referral to the completion of the patient consultation. The methodology also included model validation, identification of opportunities for improvement, investigation of alternative solutions and solution recommendations. Outcomes of the project, conducted over a 14 week semester, demonstrate that the students found the technique quick and easy to learn and that they could transfer their new found knowledge of this innovation to healthcare staff for the purposes of developing true and accurate representations of the current state patient journey. Staff were then able to interact directly with the student team, using the models as a communication medium, to identify opportunities for improvement and understand more deeply, how changes would impact their daily tasks and increase patient satisfaction in service delivery.


Asunto(s)
Difusión de Innovaciones , Modelos Teóricos , Transferencia de Pacientes , Estudiantes , Eficiencia Organizacional , Investigación sobre Servicios de Salud , Humanos , Nueva Gales del Sur , Servicio Ambulatorio en Hospital/organización & administración
7.
Physiol Behav ; 73(1-2): 75-80, 2001 May.
Artículo en Inglés | MEDLINE | ID: mdl-11399297

RESUMEN

Limbic and basal forebrain-hypothalamic regions from male sheep differing in sexual performance were quantified for fos-like immunoreactivity. Rams classified as high-sexually performing (HP), low-sexually performing (LP), and male-oriented (MO) received noncontact sensory stimulation from either ewes in estrus (HP, n=5; LP, n=4; MO, n=4) or other males (HP, n=5; LP, n=4; MO, n=5) for a 4-h period on each of 3 consecutive days. Following exposure to stimulus animals on the third day, rams were euthanized and their brains were perfused with a 1% paraformaldehyde/1.5% glutaraldehyde solution and sections were analyzed for fos-like immunoreactivity. Brain regions analyzed were the medial amygdala (meAMY), medial preoptic area (mPOA), bed nucleus of the stria terminalis (BNST), and ventromedial hypothalamic nucleus (VMH). Fos-like immunoreactivity differed between groups in the mPOA and BNST but not in the meAMY or VMH. LP rams exposed to estrous ewes had more (P<.05) neurons staining positive for fos and fos-related antigens (FRA) in the mPOA and BNST than LP rams exposed to other rams or MO rams exposed to either estrous ewes or other rams. Numbers of neurons staining positive for FRA in the mPOA and BNST of LP rams exposed to estrous ewes, however, were not different (P>.05) from HP rams exposed to either estrous ewes or other rams. The similar fos-like immunoreactivity in areas important for the display of sexual behavior in HP and LP rams may reflect similar sensory input in these two groups of rams; however, LP rams, in contrast to HP rams, do not appear to respond similarly to the same sensory stimulus.


Asunto(s)
Encéfalo/fisiología , Proteínas Proto-Oncogénicas c-fos/metabolismo , Conducta Sexual Animal/fisiología , Amígdala del Cerebelo/anatomía & histología , Amígdala del Cerebelo/fisiología , Animales , Encéfalo/anatomía & histología , Mapeo Encefálico , Femenino , Masculino , Área Preóptica/anatomía & histología , Área Preóptica/fisiología , Núcleos Septales/anatomía & histología , Núcleos Septales/fisiología , Ovinos , Medio Social , Núcleo Hipotalámico Ventromedial/anatomía & histología , Núcleo Hipotalámico Ventromedial/fisiología
8.
Behav Brain Res ; 119(1): 15-21, 2001 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-11164521

RESUMEN

Brain regions of male sheep behaviorally classified as high-sexually performing (n=10), low-sexually performing (n=8) or male-oriented (n=9) were examined to determine if differences in reproductive behavior were associated with differences in density or sizes of neurons. High-sexually performing rams actively mounted estrous ewes, low-sexually performing rams failed to mount or had long latencies to mounting estrous ewes, and male-oriented rams mounted other rams in preference to ewes in estrus. Cell densities and sizes were quantified in Nissl stained sections through the medial amygdala (meAMY), preoptic area (POA), bed nucleus of the stria terminalis (BNST), ventromedial hypothalamic nucleus (VMH), lateral geniculate nucleus (LG) and medial geniculate nucleus (MG). Multivariate discriminant analysis based on soma sizes within nuclei of known importance for reproductive behavior and/or gonadotropin release (meAMY, POA, BNST and VMH) discriminated (Wilks Lambda P<0.05) low-performing rams from high-performing and male-oriented rams, but did not discriminate (Wilks Lambda P=0.14) between high-performing and male-oriented rams. Cell size in the parvocellular and magnocellular layers of the LG along with cells of the MG, structures without a specific role in reproduction, did not discriminate any of the three behaviorally defined groups of rams (Wilks Lambda P=0.57). Density of cells present in structures important for the display of reproductive behavior (POA, meAMY, BNST) and/or gonadotropin release (POA, VMH) had no discriminating power nor did density of cells in structures important for the processing of visual (LG) or auditory (MG) stimuli. In conclusion, significant differences in sizes of cells located within nuclei that are specifically important for the display of male reproductive behavior were found in low-sexually performing rams compared to high-sexually performing and male-oriented rams. These differences may result from neuron development in utero or occur later as a consequence of endocrine factors or behavioral experience. Neuronal cell size is a critical variable that determines excitability to synaptic inputs because cell surface area varies exponentially with cell diameter. Relatively small differences in neuron diameter could relate to functionally important differences in neuronal excitability.


Asunto(s)
Amígdala del Cerebelo/citología , Área Preóptica/citología , Conducta Sexual Animal/fisiología , Amígdala del Cerebelo/ultraestructura , Animales , Recuento de Células , Tamaño de la Célula , Cuerpos Geniculados/citología , Cuerpos Geniculados/ultraestructura , Masculino , Neuronas/ultraestructura , Área Preóptica/ultraestructura , Ovinos
9.
J Anim Sci ; 77(10): 2757-65, 1999 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-10521038

RESUMEN

Yearling ewes (n = 32) were used in a 2x2x2 factorial experiment to determine effects of breed (Targhee vs. Suffolk), energy intake (1x vs. 3x NEm requirements, and physiological status (nonpregnant, nonlactating vs. lactating) on serum GH, insulin, NEFA, glucose, and blood urea nitrogen (BUN) concentrations. Blood collections were made in two periods that began 21 and 32 d after ewes lambed. Lactating ewes had more GH peaks (P<.10), higher (P<.01) mean GH concentration, and greater (P<.01) area under the GH curve (AUC) than nonlactating ewes. The AUC was greater (P<.01) in ewes fed 1x NEm than in ewes fed 3x NEm. Energy intake had no effect on serum GH before feeding (P>.23) when evaluated within physiological statuses. After feeding, GH concentrations were greater (P<.10) for ewes fed 1x NEm than for those fed 3x NEm. Insulin and glucose did not differ (P>.23) between energy intake levels. Insulin and glucose were greater (P<.001) in nonlactating than in lactating ewes when evaluated within breed. Lactating and Targhee ewes fed 1x NEm had greater (P<.001) NEFA concentration than nonlactating and Targhee ewes fed 3x NEm, respectively. Ewes fed 3x NEm and Targhee ewes had greater (P<.005) BUN concentrations than ewes fed 1x NEm and Suffolk ewes, respectively. Physiological status seems to play a more important role in the regulation of GH than does energy intake. Higher BUN concentrations in Targhee than in Suffolk ewes demonstrates one metabolic event that distinguishes a breed's adaptation to the environment in which it originated.


Asunto(s)
Ingestión de Energía , Metabolismo Energético , Hormona del Crecimiento/sangre , Insulina/sangre , Ovinos/fisiología , Animales , Glucemia/análisis , Nitrógeno de la Urea Sanguínea , Peso Corporal , Ácidos Grasos no Esterificados/sangre , Femenino , Ovinos/sangre
10.
J Anim Sci ; 77(7): 1869-74, 1999 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-10438035

RESUMEN

High-performing, low-performing, and male-oriented rams were used to investigate behavior and neuroendocrine correlates of sexual interest and discrimination. Treatment consisted of visual and olfactory contact with stimulus animals through a woven wire fence, which inhibited copulation (either ewes in estrus or other rams), for 4 h on each of three consecutive days. Before exposure to stimulus animals on d 1 and during the final 1 h of exposure on d 2, blood samples were collected every 15 min for 1 h to determine concentrations of LH and testosterone. During exposure to stimulus animals, rams were continuously observed and investigatory behaviors were recorded. There was no day effect for any behavior. Groups of rams differed (P < .05) in amounts of behaviors exhibited, but behaviors were not influenced by sex of stimulus animals. High-performing rams exhibited more (P < .05) investigatory behaviors toward stimulus animals than low-performing or male-oriented rams. Plasma concentrations of LH increased (P < .05) in high-performing rams following exposure to estrous ewes, but not following exposure to rams. In low-performing and male-orientated rams, concentrations of LH were unchanged regardless of sex of the stimulus animal. Change in plasma concentrations of testosterone from pre- to posttreatment did not differ between high-performing, low-performing, and male-oriented rams. However, low-performing rams exhibited an increase (P < .05) in plasma concentrations of testosterone following exposure to rams. In conclusion, high-performing rams exhibit a high degree of investigatory behaviors toward estrous ewes and other rams. High-performing rams seem to discriminate sex of stimulus animals and exhibit a neuroendocrine response (i.e., increased plasma LH) only when exposed to ewes in estrus. The sensory signals provided by estrous females are either not detected by low-performing or male-oriented rams or are not sufficiently provocative to elicit further investigation by these rams.


Asunto(s)
Estro , Conducta Sexual Animal , Porcinos/fisiología , Animales , Copulación , Femenino , Hormona Luteinizante/sangre , Masculino , Porcinos/sangre , Testosterona/sangre
11.
Am J Gastroenterol ; 92(1): 89-94, 1997 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8995944

RESUMEN

BACKGROUND AND OBJECTIVES: We investigated the possibility that a variant of the normal colonic flora, a high concentration of methanogens, influences the host's response to ingestion of nonabsorbable, fermentable materials. METHODS: To better evaluate symptomatic and breath H2 and methane (CH4) responses, subjects were placed on a basal diet (primarily rice and hamburger) that contained minimal amounts of nonabsorbable, fermentable substrate. A breath CH4/H2 ratio of greater or less than 1 on the second day of the basal diet was used to categorize subjects as high (N = 9) or low (N = 25) CH4 producers. After stabilization of the breath gas excretion (day 3 or 4 on the basal diet), the subjects ingested either sorbitol (8.8 g) or oat fiber (10.2 g). RESULTS: The low CH4 producers had a significantly higher (p < 0.05) breath H2 concentration than the high producers on the basal diet and after ingestion of sorbitol (27.1 +/- 2.7 ppm vs 15.8 +/- 3.6 ppm) or oat fiber (13.1 +/- 0.08 ppm vs 9.6 +/- 1.2 ppm). Low producers of methane reported significantly increased bloating and cramping after sorbitol ingestion and increased bloating after fiber ingestion, whereas high CH4 producers reported no significant increase in these symptoms. CONCLUSION: The presence of a methanogenic flora is associated with a reduced symptomatic response to ingestion of nonabsorbable, fermentable material in healthy subjects. Manipulation of the normal flora could be of therapeutic value in nonmethanogenic patients with irritable bowel syndrome.


Asunto(s)
Pruebas Respiratorias , Dieta , Fibras de la Dieta/farmacología , Euryarchaeota/metabolismo , Hidrógeno/metabolismo , Intestinos/microbiología , Sorbitol/farmacología , Avena , Dieta/efectos adversos , Registros de Dieta , Flatulencia/etiología , Humanos , Hidrógeno/análisis
12.
J Anim Sci ; 74(9): 2152-7, 1996 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8880417

RESUMEN

Targhee ewes (n = 22, average age 5 yr) rearing twin lambs were used to investigate serum growth hormone (GH), IGF-I, triiodothyronine (T3), thyroxine (T4), and prolactin (PRL; ewes only) concentrations associated with selection pressure for lifetime production of kilograms of lamb weaned per ewe. Period 1 started on d 4 after birth and was conducted in confinement. Periods 2, 3, and 4 were conducted on fenced intermountain sagebrush-bunchgrass range starting at an average of 49, 84, and 112 d after birth, respectively. Blood samples were collected hourly for 6 h on d 4, 11, 18, 25, 49, 84, and 112 after lambing. Ewe models included the fixed effect for line, with ewe age, lambing date, and starting weight nested within line as potential covariables. Lamb models included fixed effects for line, sex, and sibling sex, with lamb age and birth weight nested within line tested as possible covariables. Growth hormone concentrations were greater (P = .06) for selected than for control ewes, but lamb GH concentrations did not differ (P = .90) between selected and control lambs. Ewe prolactin concentration tended (P = .13) to be greater for control than selected ewes. Ewe and lamb IGF-I did not differ (P > .55) between selected and control ewes and lambs. Ewe T3 and T4 concentrations did not differ (P > .19) between selected and control ewes; however, lamb T3 and T4 concentrations were greater (P < .01) for control than for selected lambs. Increased GH concentration in selected ewes seemed to be associated with greater milk production. Differences in selected and control lamb T3 and T4 concentrations could be an indicator of receptor sensitivity, metabolic activity, or seasonal reproductive transitions in ewe lambs.


Asunto(s)
Envejecimiento/sangre , Hormona del Crecimiento/sangre , Factor I del Crecimiento Similar a la Insulina/análisis , Prolactina/sangre , Selección Genética , Ovinos/crecimiento & desarrollo , Ovinos/metabolismo , Tiroxina/sangre , Triyodotironina/sangre , Animales , Peso al Nacer , Femenino , Fertilidad/fisiología , Masculino , Estaciones del Año , Ovinos/genética , Factores de Tiempo
13.
Biol Reprod ; 55(1): 120-6, 1996 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-8793066

RESUMEN

We studied a unique group of rams that would not mate with estrous ewes during extensive testing for sexual behavior. The same rams courted males in preference to females in 30-min sexual preference tests and were classified as male-oriented (n = 6). We compared the following endocrine profiles: systemic steroid concentrations, the capacity of the testes to biosynthesize 17 alpha-hydroxyprogesterone and testosterone from 3H-progesterone in vitro, and the levels of brain aromatase activity (AA) in male-oriented rams vs. rams that were proven breeders and designated as female-oriented (n = 7). After the last behavioral test, sera were collected, and males in each experimental group were killed. Brains and testes were obtained for subsequent determinations of AA and measurements of steroidogenic enzyme activity. All dissections and subsequent assays were performed without knowledge of experimental group assignments. Serum concentration of testosterone (T), dihydrotestosterone (DHT), androstenedione, estrone (E1), and estradiol-17 beta (E2) were determined by RIA. AA was quantified by a 3H2O assay validated for neural tissue of the ram. We studied frontal, parietal and cingulate cortex, cerebellum, hippocampus, olfactory bulb, septum, amygdala, infundibulum-median eminence, and preoptic area (POA). Serum T, E1, and E2 concentrations of female-oriented subjects were significantly higher (p < 0.05) than those in male-oriented subjects (SEM: 1559 +/- 228, 46 +/- 2, and 15 +/- 3 pg/ml vs. 874 +/- 196, 40 +/- 2, and 8 +/- 1 pg/ml serum, respectively). DHT and androstenedione concentrations in the systemic circulation did not differ between groups. Likewise, biosynthesis of labeled T and 17 alpha-hydroxyprogesterone from 3H-progesterone by testicular homogenates in vitro was significantly higher (p < 0.05) in female-oriented than in male-oriented subjects (28.8 +/- 8.1 vs. 12.1 +/- 2.3 mumol.h-1.mg protein-1 for T and 416.9 +/- 100.8 vs. 186.3 +/- 30.7 mumol.h-1.mg protein-1 for 17 alpha-hydroxyprogesterone). The highest level of AA was found in the POA, which was significantly greater in female-oriented than in male-oriented rams (472 +/- 34 vs. 296 +/- 24 fmol 3H2O.h-1.mg protein-1, p < 0.05). AA in other brain areas did not differ between experimental groups. Our data suggest that the testes of the male-oriented ram have reduced capacity for T production. In other species, T controls in situ estrogen formation not only by providing substrate for aromatization but also by up-regulating P450arom mRNA in the POA. Because the POA is part of a neural circuitry that mediates male sexual behavior in many species, we hypothesize that the capacity for aromatization influences sexual orientation of these rams.


Asunto(s)
Hormonas Esteroides Gonadales/sangre , Homosexualidad Masculina , Conducta Sexual Animal/fisiología , Ovinos , 17-alfa-Hidroxiprogesterona/metabolismo , Androstenodiona/sangre , Animales , Aromatasa/metabolismo , Encéfalo/enzimología , Dihidrotestosterona/sangre , Estradiol/sangre , Estrona/sangre , Femenino , Masculino , Área Preóptica/enzimología , Progesterona/metabolismo , Testículo/metabolismo , Testosterona/biosíntesis , Testosterona/sangre
14.
Horm Behav ; 29(1): 31-41, 1995 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-7782061

RESUMEN

This study examined endocrine components of sexual orientation of male sheep. Sexual orientation of adult rams was identified through standardized sexual performance tests. Four rams that copulated with ewes, four rams that never mounted females and copulated with males, and eight ewes were used in the experiments. Exogenous estradiol benzoate (50 micrograms, i.m.) stimulated (P < .05) a preovulatory-like LH surge 16-22 hr after administration to females. Estradiol did not (P > .05) affect LH release of heterosexual or homosexual rams. Thirty days after the estradiol challenge, sheep were euthanized and areas of the amygdala (AMY), hypothalamus (HYP), anterior pituitary (AP), and preoptic area (POA) of the hypothalamus were collected. Occupied and unoccupied content of estradiol receptors (ER) was determined. The content of ER in the amygdala of both homosexual rams and ewes was similar, but less than (P < .05) the content of ER in heterosexual rams. The ER content measured in other brain regions did not differ by sex or orientation. In summary, results from these data show that the preovulatory LH surge mechanism that is a characteristic of the female does not occur in either homosexual or heterosexual rams. Conversely, the ER content of the AMY of homosexual rams is similar to that of ewes and differs from the heterosexual male. Differences in ER content between heterosexual and homosexual rams imply that the amygdala serves as a link for input from potential mates. These data suggest that the amygdala not only plays a role in sexual behavior but may be involved in sexual orientation of rams.


Asunto(s)
Encéfalo/fisiología , Homosexualidad Masculina , Hormona Luteinizante/sangre , Receptores de Estradiol/fisiología , Conducta Sexual Animal/fisiología , Ovinos/fisiología , Animales , Mapeo Encefálico , Copulación/fisiología , Estradiol/fisiología , Femenino , Masculino , Ovulación/fisiología , Medio Social
15.
Domest Anim Endocrinol ; 11(3): 271-9, 1994 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-7956174

RESUMEN

Effects of the opiate agonist, morphine, and antagonist, naloxone, on LH release, courtship behavior and ejaculation frequency of mature, sexually active or sexually inactive rams were investigated. Plasma LH concentrations were monitored from blood samples collected every 15 min for 10 hr (0800 to 1800 hr) from eight rams that were isolated from or in contact with estrous females. Plasma LH concentration was higher (P < .05) in sexually active rams exposed to receptive females compared with hormone concentration of rams isolated from ewes. Intravenous infusion of morphine sulphate (1 mg/kg) into rams 4 and 6 hr after exposure to ewes reduced (P < .05) plasma LH concentration as compared to rams given saline. Morphine did not affect (P > .05) courtship behavior (investigatory sniff, mount attempt, foreleg kick, flehmen, vocalization) but diminished (P < .05) number of ejaculations. In another trial, LH concentrations were higher (P < .05) in seven sexually active rams given naloxone iv or when given to three rams through an intracerebroventricular cannula (icv) as compared to LH response of sexually inactive rams. LH did not differ (P > .05) in seven sexually inactive rams before or after administration of naloxone. Investigatory sniffs by sexually active rams were increased (P < .03) after treatment with the opiate antagonist. Four of the seven sexually active rams had more ejaculations after naloxone compared with the pretreatment period, but mean ejaculation frequency after treatment did not differ (P = .31). Naloxone did not stimulate courtship behavior of sexually inactive males.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Hormona Luteinizante/metabolismo , Morfina/farmacología , Naloxona/farmacología , Conducta Sexual/efectos de los fármacos , Ovinos/fisiología , Animales , Eyaculación/efectos de los fármacos , Infusiones Intravenosas , Inyecciones Intraventriculares , Hormona Luteinizante/sangre , Masculino , Morfina/administración & dosificación , Naloxona/administración & dosificación
16.
J Anim Sci ; 72(1): 51-5, 1994 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-8138503

RESUMEN

The objective of this study was to test whether the sexual behavior of the ram affects the ram effect. Rams exhibiting either high (HP) or low (LP) levels of sexual performance (on the basis of serving capacity tests) were exposed to 89 anestrous ewes for 28 d. Thirty-two anestrous ewes were not exposed to rams. The objective of this study was to compare the efficacy of estrus induction by HP (n = 4) vs LP (n = 4) rams. Plasma progesterone concentration was used as an index of ovarian activity. Groups of ewes were exposed to either an HP or an LP ram in a .32-ha pasture. Courtship behaviors of rams were recorded for 6 h on the initial day of exposure and for 30-min periods on alternate days thereafter. A greater percentage of ewes exposed to HP rams ovulated (95%) compared with ewes exposed to LP rams (78%) (P < .02). On the 1st d of exposure, the HP rams exhibited more courtship behavior and spent more time near the ewes (P < .04). The HP rams spent more time within 1 m of ewes during the 28-d exposure. There were no differences in the amount of contact with rams (LP or HP) between rise in progesterone indicate of ovulation tended to occur earlier (P = .06) in ewes penned with HP rams. A greater percentage of ewes exposed to LP rams (P = .03) had early elevations of progesterone with no concurrent sexual behavior. These data imply that in addition to a pheromone the sexual behavior of the ram may be important in initiating ovarian cycle activity.


Asunto(s)
Anestro/fisiología , Sincronización del Estro , Ovulación/fisiología , Conducta Sexual Animal , Ovinos/fisiología , Animales , Femenino , Masculino , Progesterona/sangre , Distribución Aleatoria
17.
Physiol Behav ; 54(6): 1191-4, 1993 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-8295963

RESUMEN

The mechanisms underlying diet selection of ruminants are less studied than those for monogastrics. However, recent studies have shown that these mechanisms may be more similar in ruminants and monogastrics than previously believed. Food aversion learning is observed in both monogastrics and ruminants, and the hypothalamic-pituitary-adrenal axis appears to be involved in avoidance learning. Using leafy spurge (Euphorbia esula), an introduced weed whose expansion has costly ecological and economic implications in western North America, as a model for underconsumed plant species, we hypothesized that sheep experience increased cortisol levels when they first consume leafy spurge and that this may be related to their reluctance to graze it. We also hypothesized that preexposure to leafy spurge would attenuate the development of a spurge-based aversion. Correspondingly, we hypothesized that preexposed sheep would not experience increased blood cortisol levels with leafy spurge gavage during an aversion trial. None of our hypotheses were disproved by the experiments. Our results lend support to the hypothesis that stress is required for the development of conditioned taste aversions and extend it to ruminants. We suggest that activity of the hypothalamic-pituitary-adrenal axis is integral to food aversion learning in ruminants.


Asunto(s)
Nivel de Alerta/fisiología , Conducta Alimentaria/fisiología , Sistema Hipotálamo-Hipofisario/fisiología , Sistema Hipófiso-Suprarrenal/fisiología , Ovinos/fisiología , Estrés Psicológico/complicaciones , Animales , Reacción de Prevención/fisiología , Condicionamiento Clásico/fisiología , Femenino , Hidrocortisona/sangre , Masculino
18.
Horm Behav ; 27(3): 296-307, 1993 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-8225254

RESUMEN

Rams, characterized over a 3-year period as being high (n = 8) or low (n = 10) sexual performers, were euthanized to determine if differences in sexual behavior were associated with differences in hypophyseal and hypothalamic receptors for estradiol. Rams were exposed to estrous ewes and courtship behavior was recorded for 5 hr prior to tissue collection. Blood samples for determination of serum concentrations of luteinizing hormone (LH) were collected every 15 min during the behavior testing period. Hourly blood samples were analyzed for serum concentrations of estradiol (E) and testosterone (T). Rams characterized as high (HP) or low (LP) sexual performers had similar LH profiles; there were no differences noted in basal concentration, number of pulses, or pulse amplitude of LH. There were no differences in serum concentrations of T or E during the behavior testing period between HP and LP rams. Unoccupied receptors for E (moles E bound x 10(-15)) in the stalk-median eminence (SME) (P < 0.05) in HP rams (15.1 +/- 3.1) were greater than those in LP rams (4.6 +/- 1.9). Occupied receptors for E (moles E bound x 10(-15)) in the preoptic area (POA) (P < 0.1) in HP rams (6.0 +/- 0.8) tended to be greater than those in the LP rams (3.8 +/- 0.8). The proportion of total E receptors (occupied+unoccupied) in the POA that were occupied was greater (P < 0.05; 0.41 +/- 0.03 vs 0.23 +/- 0.04) for HP than for LP rams. In contrast, HP rams had less (P < 0.05) occupied E receptors (moles E bound x 10(-15)) in the anterior pituitary gland (AP) than LP rams (152.0 +/- 38.5 vs 337.3 +/- 51.7). The proportion (%) of E receptors that were occupied in the AP in HP rams also tended to be less (P < 0.06) than that in LP rams (8 +/- 2 vs 14 +/- 1). No differences were detected in occupied or unoccupied E receptors in the medial basal hypothalamus, medial amygdala, or stalk-median eminence. In conclusion, differences in occupied receptors for E in the POA and the AP, and unoccupied receptors for E in the SME, were associated with differences in ram sexual behavior.


Asunto(s)
Sistema Hipotálamo-Hipofisario/fisiología , Libido/fisiología , Receptores de Estradiol/fisiología , Conducta Sexual Animal/fisiología , Ovinos/fisiología , Amígdala del Cerebelo/fisiología , Animales , Mapeo Encefálico , Estro/fisiología , Femenino , Hormona Luteinizante/sangre , Masculino , Eminencia Media/fisiología , Adenohipófisis/fisiología , Área Preóptica/fisiología , Testosterona/sangre
19.
J Anim Sci ; 71(3): 618-24, 1993 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-8463148

RESUMEN

Thirty-four white-face wethers (avg BW 56 kg) were used in two experiments to investigate differences in plasma cortisol, forage intake, fecal output, and BW change associated with two methods of estimating fecal output. The methods were fecal collection bags (B) and marker estimates of fecal output (U). A control treatment (C) was included in each experiment in which wethers were not bagged or dosed with the marker. Experiment 1 was conducted with wethers grazing dormant sagebrush-bunchgrass range. Experiment 2 was conducted with wethers housed in metabolism crates. In Exp. 1, the following differences were detected: 1) basal and mean integrated (following ACTH challenge) plasma cortisol levels were higher (P < .05) for U wethers than for C wethers, 2) no differences (P > .05) between B and C wethers were detected for basal or mean integrated plasma cortisol, 3) both B and U wethers gained (P < .05) weight, whereas C wethers lost weight, and 4) no differences (P > .05) between B and U wethers were detected for cortisol measurements, weight change, or fecal output. No differences (P > .05) were noted for any of the variables tested in Exp. 2. When treatments were combined within experiment to test Exp. 1 vs 2, time to peak cortisol levels was longer (P < .05) and mean integrated cortisol levels and weight change were lower (P < .05) for wethers in confinement than for wethers on range. No difference (P > .05) was detected for basal cortisol levels.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Peso Corporal , Defecación , Ingestión de Alimentos , Hidrocortisona/sangre , Ovinos/fisiología , Animales , Masculino , Análisis de Regresión , Ovinos/sangre , Ovinos/crecimiento & desarrollo , Manejo de Especímenes/veterinaria
20.
J Anim Sci ; 70(9): 2722-5, 1992 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-1399886

RESUMEN

The purpose of this study was to determine the extent to which sexual performance (serving capacity) tests can be used to predict the sexual behavior and reproductive success of rams in the context of pen mating. Standard serving capacity tests were used to select four low (LP) and four high-performing (HP) rams from a population of 94 yearling males. Each selected ram was then exposed to approximately 30 estrus-synchronized ewes for a 9-d period. Ejaculations observed and mounting marks left on ewes confirmed the greater (P less than .001) sexual activity of the HP rams in the field. In addition, ewes exposed to HP rams had a higher lambing percentage, more lambs born, and more live lambs born per ewe. Ram classification was not related (P greater than .60) to the number of lambs born per ewe lambing (prolificacy). It was concluded that serving capacity tests, properly conducted, can be used to predict ram mating performance and thus aid in establishing more efficient ram-to-ewe stocking rates.


Asunto(s)
Cruzamiento , Fertilidad , Conducta Sexual Animal , Ovinos/fisiología , Animales , Eyaculación , Sincronización del Estro , Femenino , Fertilidad/genética , Masculino , Ovinos/genética
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...