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1.
Epidemiol Infect ; 147: e266, 2019 09 09.
Artículo en Inglés | MEDLINE | ID: mdl-31496454

RESUMEN

We studied trends in the incidence of health care-associated infections (HAIs) in LTCFs between 2009 and 2015 and determined the effect of participation in our network. Elder-care physicians reported weekly the number of cases of influenza-like illness, gastroenteritis, (probable) pneumonia, urinary tract infections (UTIs) and all-cause mortality. Trends in the incidence of infection and mortality in relation to LTCF characteristics were calculated using multilevel univariate and multivariate logistic regression. Thirty LTCF participated for 3 years or more, 16 for 2 years and the remaining 12 LTCF for 1 year. During the study period, the median number of beds decreased from 158 to 139, whereas the percentage of residents with private bedrooms increased from 14% to 87%. UTIs were the most frequently reported infections, followed by (probable) pneumonia and gastroenteritis. Adjusted for calendar year and season, we observed a statistically significant decrease in the incidence of influenza-like illness (odds ratio (OR) = 0.8, P < 0.01) and (probable) pneumonia (OR = 0.8, P < 0.01) for each extra year an LTCF participated. Although there are other likely contributors, such as more private rooms and enhanced infection control measures, the decreasing trend of HAI in LTCFs participating in surveillance implies that surveillance is a valuable addition to current strategies to optimise infection control.


Asunto(s)
Infección Hospitalaria/epidemiología , Monitoreo Epidemiológico , Cuidados a Largo Plazo , Infección Hospitalaria/mortalidad , Instituciones de Salud , Humanos , Incidencia , Países Bajos/epidemiología , Análisis de Supervivencia
2.
Animal ; 17 Suppl 2: 100904, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37500376

RESUMEN

The search for new, alternative and sustainable feeding sources, including insects, has become an important challenge on the feed market. In 2017, the European Union (EU) started to allow the use of insect meals as feeds for fish. In addition, in 2021, the EU also authorised the use of insect meal for pig and poultry farming. However, the adoption of insect meal by the European aquaculture sector is still limited, and this is mostly due to the lack of availability of insects and their higher costs than conventional feed ingredients. Thus, the insect-based feed industry is still in its infancy, and its successful development and integration in the food value chain depend on several factors. Among these, the technical feasibility and production of quality products, and acceptance by European consumers and farmers are relevant factors. To address these points, this narrative review describes the state of the art of the potential role of insect-based feeds. The stakeholders' and consumers' perspectives are investigated, along with the effects of insect-based feeds on the production and nutritional values of fish, poultry (meat and eggs), and pork. Indeed, matching the nutritional values of insect products with conventional feeds is one of the future challenges of the insect sector, as their nutritional composition is highly dependent on the rearing substrates, and thus, their use in animal feeding needs to be investigated carefully. Feeding animals with insect-based diets affects their growth performances and the chemical composition of the derived products (fish fillets, meat, and eggs). Whether these effects can be considered positive or negative seems to depend to a great extent on the percentage of insects included in their diets and the chemical composition of the ingredients. The use of insect-based feeds has also shown a potential to improve the nutritional features and values of animal products and even to add new ones. Finally, many of the acceptance studies on the use of insects in feeds have focused mostly on the consumers' perception rather than on industry stakeholders (e.g., farmers). Future research should focus more on the farmers' perceptions on and market analyses of these innovative feeds. Even though it is likely that the upscaling of the insect sector will lead to a decrease in prices and an increase in market availability, it is still critical to understand the potential barriers and drivers for the implementation of insects as feeds from a production point of view.


Asunto(s)
Insectos , Óvulo , Animales , Porcinos , Insectos/química , Alimentación Animal/análisis , Agricultura , Dieta
3.
Infection ; 40(2): 225-8, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-21877178

RESUMEN

Healthcare-associated infections (HAI) are considered to be the most frequent adverse event in healthcare delivery. Active efforts to curb HAI have increased across Europe thanks to the growing emphasis on patient safety and quality of care. Recently, there has been dramatic success in improving the quality of patient care by focusing on the implementation of a group or "bundle" of evidenced-based preventive practices to achieve a better outcome than when implemented individually. The project entitled IMPLEMENT is designed to spread and test knowledge on how to implement strategic bundles for infection prevention and management in a diverse sample of European hospitals. The general goal of this project is to provide evidence on how to decrease the incidence of HAI and to improve antibiotic use under routine conditions.


Asunto(s)
Infección Hospitalaria/prevención & control , Hospitales/normas , Control de Infecciones/métodos , Antibacterianos/farmacología , Notificación de Enfermedades/normas , Farmacorresistencia Microbiana , Europa (Continente) , Humanos , Seguridad del Paciente , Guías de Práctica Clínica como Asunto , Garantía de la Calidad de Atención de Salud/normas , Factores de Riesgo , Encuestas y Cuestionarios
4.
Neuromuscul Disord ; 32(10): 829-835, 2022 10.
Artículo en Inglés | MEDLINE | ID: mdl-36192279

RESUMEN

Myotonic dystrophy type 1 is a neuromuscular disorder affecting multiple organ systems and is characterized by a variety of clinical presentations. Anticipation leads to an earlier and more severe phenotype in subsequent generations. Early-onset cataract is a common initial manifestation of the late or adult-onset type of myotonic dystrophy 1. Due to its multicausal nature, early-onset cataract is often not recognized as a feature of this disease, leading to diagnostic delay resulting in consequences for successive generations, treatment and counseling. A qualitative study with semi-structured interviews was performed with purposive sampling of eight participants with myotonic dystrophy type 1 and early-onset cataract to investigate the physical and psychosocial consequences experienced due to diagnostic delay. Prior to the early-onset cataract, all participants experienced other multisystem symptoms that could have been explained by myotonic dystrophy. The diagnostic delay had severe hereditary consequences: a subsequent generation with more severely affected (grand)children was born resulting in large emotional burden for the patients. To conclude, early-onset cataract is a warning sign and ophthalmologists play a crucial role in the early detection of myotonic dystrophy type 1 by recognizing this symptom and preventing the birth of severely affected children leading to emotional and psychosocial consequences.


Asunto(s)
Catarata , Distrofia Miotónica , Humanos , Distrofia Miotónica/genética , Diagnóstico Tardío , Investigación Cualitativa , Fenotipo , Catarata/diagnóstico
5.
BJOG ; 116(13): 1773-81, 2009 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-19832827

RESUMEN

OBJECTIVE: To identify antepartum and intrapartum indicators of obstetric interventions during the expulsive second-stage arrest of labour. DESIGN: Retrospective cohort study. SETTING: The Netherlands. POPULATION: A cohort of 389,086 women with singleton, cephalic, term, live-birth deliveries from 2002 to 2004 who had entered the expulsive second stage of labour. Of all these deliveries, 37,899 (9.7%) were complicated by expulsive second-stage arrest of labour. Women with a prior Caesarean section or women undergoing an elective Caesarean section were excluded. METHODS: All deliveries in the Netherlands from 2002 to 2004 were registered in the Netherlands Perinatal Registry, which contains the linked and validated data of three databases. Uni- and multivariable logistic regression analyses were performed. MAIN OUTCOME MEASURES: Ante- and intrapartum indicators for interventions during expulsive second-stage arrest of labour. RESULTS: Primiparous delivery was the most important antepartum indicator for intervention during expulsive second-stage arrest. Using multivariable analysis the following antepartum indicators were associated with intervention for expulsive second-stage arrest of primiparous labour: maternal age, gestational age, diabetes, hypertension and labour induction. Prominent intrapartum indicators for primiparous deliveries were fetal head position and oxytocin augmentation. CONCLUSION: Multiple significant antepartum and intrapartum indicators associated with intervention for expulsive second-stage arrest of labour were identified in this large retrospective study. Prominent were the associations of parity, maternal age and fetal head position with expulsive second-stage arrest. The identified factors should be further evaluated in prospective studies that aim to develop prediction models.


Asunto(s)
Distocia/etiología , Adolescente , Adulto , Complicaciones de la Diabetes/epidemiología , Distocia/epidemiología , Distocia/cirugía , Métodos Epidemiológicos , Femenino , Edad Gestacional , Humanos , Hipertensión/complicaciones , Hipertensión/epidemiología , Presentación en Trabajo de Parto , Trabajo de Parto Inducido/efectos adversos , Edad Materna , Países Bajos/epidemiología , Paridad , Embarazo , Complicaciones del Embarazo/epidemiología , Adulto Joven
6.
Ned Tijdschr Geneeskd ; 152(46): 2514-8, 2008 Nov 15.
Artículo en Holandés | MEDLINE | ID: mdl-19055259

RESUMEN

OBJECTIVE: To investigate differences among pregnant women from various ethnic groups in terms of pregnancy care and the place of delivery. DESIGN: Descriptive, retrospective study. METHOD: Data from the Dutch Perinatal Registries during the period 1995-2002, representing a total of 1,401,892 pregnancies, were linked and analysed for perinatal care, the place of the delivery and the ethnic group of the mother. The ethnic categories defined in the registries were: Dutch, Mediterranean, other European, African, Hindu, Asian and unknown. RESULTS: Other European women and Asian women often started pregnancy care with a midwife and were not often referred to secondary care with an obstetrician. These two groups most often completed the delivery under the care of a midwife (45.3% of other European women and 44.6% of Asian women). As Hindu and African women often started pregnancy care directly with an obstetrician due to medical reasons and were often referred to secondary care during pregnancy or birth, these two groups were least likely to complete their births under the primary care of a midwife (33.1% and 28.0%, respectively). 39% of the Dutch women completed delivery with a midwife. Of those women who started the delivery under the care of a midwife, 3 out of 4 Dutch women, 1 out of 3 Mediterranean women and only 1 out of 5 Hindu women ultimately elected for a home birth. CONCLUSION: Large ethnic differences exist in both pregnancy care and preference for place of delivery and, ultimately, place of birth. This should be taken into account in policy-making and in the provision of information regarding the Dutch midwifery system.


Asunto(s)
Etnicidad , Parto Domiciliario/estadística & datos numéricos , Partería/métodos , Atención Perinatal/estadística & datos numéricos , Mortalidad Perinatal/etnología , Atención Prenatal/estadística & datos numéricos , Adulto , Femenino , Parto Domiciliario/métodos , Parto Domiciliario/normas , Hospitalización/estadística & datos numéricos , Humanos , Recién Nacido , Países Bajos , Atención Perinatal/normas , Embarazo , Resultado del Embarazo , Atención Prenatal/normas , Atención Primaria de Salud/estadística & datos numéricos , Estudios Prospectivos
7.
Ned Tijdschr Geneeskd ; 152(50): 2728-33, 2008 Dec 13.
Artículo en Holandés | MEDLINE | ID: mdl-19192586

RESUMEN

OBJECTIVE: To gain insight in recent perinatal mortality figures in The Netherlands and their relation with important risk factors, risk groups and risk selection among pregnant women. DESIGN: Retrospective cohort study. METHOD: The National Obstetrical Registrations and the National Neonatal Registration were linked into The Netherlands Perinatal Registry to prevent double counting. From this database, data on 1.3 million births in the years 2000-2006 were analysed with perinatal mortality as outcome measure. RESULTS: In 2006, perinatal mortality was 9.8 per 1000 total births (foetal mortality 6.8 per 1000 births and early neonatal mortality 3.1 per 1000 live births). Maternal age (< 20 and > or = 40 years) and high multiparity (> or = 4) were risk factors for perinatal mortality but showed low prevalence (< 3%). Non-Western ethnicity and nulliparity were important risk factors (relative risk of both 1.4) with a prevalence of 16% and 46%, respectively. The very preterm births (22.0-25.6 weeks of gestation) provided 29% ofall perinatal mortality with a mortality risk of 935 per 1000 births. Full-term births (> or = 37.0 weeks) accounted for 26% of all perinatal mortality with a mortality risk of 2.8 per 1000 births. In the full-term born group, perinatal mortality was 0.4 per 1000 births in home births, 2.7 per 1000 births in outpatient clinics and 4.5 per 1000 births when the women were referred to the gynaecologist before start of labour. CONCLUSION: At a population level, low or high maternal age and high parity are less important risk factors than expected. More detailed research is indicated into the mortality ofvery preterm births but also offull-term born children.


Asunto(s)
Mortalidad Fetal , Mortalidad Infantil , Edad Materna , Paridad , Mortalidad Perinatal , Sistema de Registros/estadística & datos numéricos , Adulto , Estudios de Cohortes , Etnicidad , Femenino , Mortalidad Fetal/etnología , Mortalidad Fetal/tendencias , Edad Gestacional , Humanos , Mortalidad Infantil/etnología , Mortalidad Infantil/tendencias , Recién Nacido , Masculino , Países Bajos , Mortalidad Perinatal/etnología , Mortalidad Perinatal/tendencias , Embarazo , Estudios Retrospectivos , Factores de Riesgo , Adulto Joven
8.
J Hosp Infect ; 98(2): 212-218, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-28690117

RESUMEN

BACKGROUND: Healthcare workers (HCWs) face specific challenges in infectious disease outbreaks, which provide unusual, new events with exposure risk. The fear of infection or new, unknown tasks in an unfamiliar setting, for example, may complicate outbreak management. AIM: To gain insight into how healthcare organizations can prepare to meet the needs of their HCWs by capturing the experiences of HCWs with patients with suspected Ebola virus disease. METHODS: We conducted 23 in-depth interviews with HCWs, of whom 20 worked in a Dutch university hospital and three worked in a regional ambulance service. We invited HCWs who cared for patients with suspected Ebola or who were on the team preparing for admission of such patients in the period 2014-2015. FINDINGS: The HCWs were stressed and anxious, but most rated their overall experience as positive. We categorized the reported experiences in three main themes, namely, experiences related to: (i) the novelty of the threat, (ii) the risk of infection and fear of transmission, and (iii) the excessive attention. Our results underline the importance of a supportive working environment suitable for crises. CONCLUSION: The experiences of HCWs dealing with patients with suspected Ebola can direct improvements in generic preparedness for highly transmissible diseases.


Asunto(s)
Control de Enfermedades Transmisibles/métodos , Manejo de la Enfermedad , Conocimientos, Actitudes y Práctica en Salud , Personal de Salud/psicología , Fiebre Hemorrágica Ebola/diagnóstico , Fiebre Hemorrágica Ebola/terapia , Exposición Profesional , Transmisión de Enfermedad Infecciosa/prevención & control , Femenino , Fiebre Hemorrágica Ebola/psicología , Fiebre Hemorrágica Ebola/transmisión , Hospitales Universitarios , Humanos , Entrevistas como Asunto , Masculino , Países Bajos
9.
J Hosp Infect ; 100(2): 183-189, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29649558

RESUMEN

BACKGROUND: Various technologies have been developed to improve hand hygiene (HH) compliance in inpatient settings; however, little is known about the feasibility of machine learning technology for this purpose in outpatient clinics. AIM: To assess the effectiveness, user experiences, and costs of implementing a real-time HH notification machine learning system in outpatient clinics. METHODS: In our mixed methods study, a multi-disciplinary team co-created an infrared guided sensor system to automatically notify clinicians to perform HH just before first patient contact. Notification technology effects were measured by comparing HH compliance at baseline (without notifications) with real-time auditory notifications that continued till HH was performed (intervention I) or notifications lasting 15 s (intervention II). User experiences were collected during daily briefings and semi-structured interviews. Costs of implementation of the system were calculated and compared to the current observational auditing programme. FINDINGS: Average baseline HH performance before first patient contact was 53.8%. With real-time auditory notifications that continued till HH was performed, overall HH performance increased to 100% (P < 0.001). With auditory notifications of a maximum duration of 15 s, HH performance was 80.4% (P < 0.001). Users emphasized the relevance of real-time notification and contributed to technical feasibility improvements that were implemented in the prototype. Annual running costs for the machine learning system were estimated to be 46% lower than the observational auditing programme. CONCLUSION: Machine learning technology that enables real-time HH notification provides a promising cost-effective approach to both improving and monitoring HH, and deserves further development in outpatient settings.


Asunto(s)
Instituciones de Atención Ambulatoria , Infección Hospitalaria/prevención & control , Adhesión a Directriz , Higiene de las Manos , Aprendizaje Automático , Costos y Análisis de Costo , Humanos , Proyectos Piloto , Factores de Tiempo
10.
Acta Paediatr Suppl ; 404: 65-71, 1994 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-7841636

RESUMEN

Two cohorts of substance-using women were compared retrospectively. From 1969 to 1979 a very high perinatal mortality rate (PMR 9.8%) was found among 92 polydrug-using women (1 twin excluded). Preterm delivery occurred in 25% of all pregnancies and in 30% of the children birth weight was below the 10th percentile. Nineteen women using heroin only had a worse fetal outcome (PMR 32%, preterm delivery in 47%, birth weight < 10th percentile in 42%). These results led to a strict surveillance system. In the period 1980-1989, 240 women (4 twins excluded) delivered after 16 weeks. Total fetal loss decreased to 2.1% and PMR to 0.4%, which was similar to results in controls. However, 22% of the women still delivered before 37 weeks and 27% delivered a child < 10th percentile. Methadone-using women were able to halve their dosage during pregnancy and 16 were detoxified. Multivariate analysis within the substance users of the second cohort showed that the neonatal abstinence syndrome, but not the (registered) amount of opiates used, was related to a lower birth weight. Not coping with prenatal care was related to a shorter pregnancy length. Multivariate analysis, including the controls, showed a significant relation of birth weight (345 g lower) with substance use. Also, head circumference was 0.8 cm smaller. Length of pregnancy however was related to smoking. This study shows that it is difficult to make substance users attend prenatal care, but also that women coping with prenatal care reduce substance intake. Opiate use might be responsible for lower birth weight, although not in a clear dose-response relationship, whereas lifestyle, as represented by not coping with prenatal care and the quantity of cigarette smoking, shortens the length of pregnancy.


Asunto(s)
Complicaciones del Embarazo , Resultado del Embarazo , Trastornos Relacionados con Sustancias/complicaciones , Adulto , Estudios de Cohortes , Femenino , Humanos , Recién Nacido , Masculino , Análisis Multivariante , Síndrome de Abstinencia Neonatal/inducido químicamente , Síndrome de Abstinencia Neonatal/epidemiología , Países Bajos/epidemiología , Vigilancia de la Población , Embarazo , Complicaciones del Embarazo/epidemiología , Complicaciones del Embarazo/psicología , Resultado del Embarazo/epidemiología , Atención Prenatal , Estudios Retrospectivos , Trastornos Relacionados con Sustancias/epidemiología , Trastornos Relacionados con Sustancias/psicología
11.
Acta Paediatr Suppl ; 404: 32-5, 1994 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-7531040

RESUMEN

To study the effects of cocaine use in pregnancy in Amsterdam, clinical data on cocaine-using pregnant women (n = 21) and their offspring (n = 23) were obtained retrospectively (1987-1994) at the Academic Medical Center, Amsterdam. Infants exposed to cocaine had a median gestational age of 39 weeks and a median birth weight of 3090 g. There were six preterm infants, two small-for-gestational-age infants and five infants with a small head circumference. Three infants had a congenital malformation. One infant (Potter's syndrome) died shortly before birth. One infant had congenital syphilis, four had intracerebral abnormalities on ultrasound and four had abnormal neurologic symptoms in the neonatal period. One infant died after 21 days of life. At follow-up four infants showed abnormal development. In 12 of the 23 infants (52%), one or more possible effects of cocaine were found.


Asunto(s)
Cocaína , Complicaciones del Embarazo/epidemiología , Trastornos Relacionados con Sustancias/epidemiología , Hijo de Padres Discapacitados , Discapacidades del Desarrollo/inducido químicamente , Discapacidades del Desarrollo/epidemiología , Femenino , Estudios de Seguimiento , Humanos , Lactante , Recién Nacido , Masculino , Países Bajos/epidemiología , Vigilancia de la Población , Embarazo , Resultado del Embarazo/epidemiología , Estudios Retrospectivos , Trastornos Relacionados con Sustancias/complicaciones , Salud Urbana
12.
J Hosp Infect ; 87(4): 203-11, 2014 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-24973016

RESUMEN

BACKGROUND: There is evidence that meticillin-resistant Staphylococcus aureus (MRSA) bacteraemia can be reduced with improved infection control and antibiotic stewardship. AIM: To survey infection control and antibiotic stewardship practices within European hospitals and to identify initiatives that correlate with reduced MRSA prevalence. METHODS: Online questionnaires were sent to European hospitals about their surveillance, hand hygiene, intravenous device management, admission screening, isolation, antibiotic prescribing, hospital demographics and MRSA blood culture isolates during 2010. FINDINGS: In all, 269 replies were received from hospitals in 29 European countries. Lower MRSA prevalence showed significant association with presence of incidence surveillance, performance of root cause analysis, mandatory training requirements for hand hygiene, accountability measures for persistent non-compliance, and multi-stakeholder teamwork in antibiotic prescribing. Presence of policies on intravenous catheter insertion and management showed no variation between different MRSA prevalence groups. However, low-prevalence hospitals reported more competency assessment programmes in insertion and maintenance of peripheral and central venous catheters. Hospitals from the UK and Ireland reported the highest uptake of infection control and antibiotic stewardship practices that were significantly associated with low MRSA prevalence, whereas Southern European hospitals exhibited the lowest. In multiple regression analysis, isolation of high-risk patients, performance of root cause analysis, obligatory training for nurses in hand hygiene, and undertaking joint ward rounds including microbiologists and infectious disease physicians remained significantly associated with lower MRSA prevalence. CONCLUSION: Proactive infection control and antibiotic stewardship initiatives that instilled accountability, ownership, teamwork, and validated competence among healthcare workers were associated with improved MRSA outcomes.


Asunto(s)
Bacteriemia/prevención & control , Infección Hospitalaria/prevención & control , Utilización de Medicamentos/normas , Control de Infecciones/métodos , Staphylococcus aureus Resistente a Meticilina/aislamiento & purificación , Infecciones Estafilocócicas/prevención & control , Antibacterianos/uso terapéutico , Bacteriemia/epidemiología , Bacteriemia/microbiología , Infección Hospitalaria/epidemiología , Infección Hospitalaria/microbiología , Estudios Transversales , Europa (Continente) , Política de Salud , Hospitales , Humanos , Prevalencia , Infecciones Estafilocócicas/epidemiología , Infecciones Estafilocócicas/microbiología , Encuestas y Cuestionarios
13.
Bull Entomol Res ; 95(4): 341-7, 2005 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-16048682

RESUMEN

Development and reproductive success of the solitary egg parasitoid Uscana lariophaga Steffan were examined after development in eggs of the bruchid storage pest Callosobruchus maculatus Fabricius reared at either low or high densities on cowpea seeds and laid at day 1 and 4 of maternal life. Both bruchid larval competition and maternal age negatively affected egg size, but the latter more than the former. Uscana lariophaga reared in small hosts developed slower, were smaller and produced fewer eggs compared to parasitoids reared in large hosts. Fecundity of the parasitoid was heavily influenced by host egg size. This was reflected in the values for the intrinsic rate of increase of U. lariophaga, which differed for wasps that developed in host eggs laid by bruchid females of different age. Wasps allocated marginally more female offspring to larger hosts.


Asunto(s)
Escarabajos/parasitología , Himenópteros/fisiología , Oviposición/fisiología , Animales , Fabaceae/parasitología , Femenino , Fertilidad/fisiología , Interacciones Huésped-Parásitos , Masculino , Óvulo/parasitología , Densidad de Población , Semillas/parasitología , Razón de Masculinidad
14.
J Chem Ecol ; 31(7): 1537-53, 2005 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-16222791

RESUMEN

As a response to attack by herbivores, plants can emit a variety of volatile substances that attract natural enemies of these insect pests. Predators of the banana weevil, Cosmopolites sordidus (Germar) (Coleoptera: Curculionidae) such as Dactylosternum abdominale (Coleoptera: Hydrophilidae) and Pheidole megacephala (Hymenoptera: Formicidae), are normally found in association with weevil-infested rotten pseudostems and harvested stumps. We investigated whether these predators are attracted to such environments in response to volatiles produced by the host plant, by the weevil, or by the weevil plant complex. We evaluated predator responses towards volatiles from banana pseudostem tissue (synomones) and the synthetic banana weevil aggregation pheromone Cosmolure+ in a two-choice olfactometer. The beetle D. abdominale was attracted to fermenting banana pseudostem tissue and Cosmolure+, whereas the ant P. megacephala was attracted only to fermented pseudostem tissue. Both predators were attracted to banana pseudostem tissue that had been damaged by weevil larvae irrespective of weevil presence. Adding pheromone did not enhance predator response to volatiles from pseudostem tissue fed on by weevils. The numbers of both predators recovered with pseudostem traps in the field from banana mats with a pheromone trap were similar to those in pseudostem traps at different distance ranges from the pheromone. Our study shows that the generalist predators D. abdominale and P. megacephala use volatiles from fermented banana pseudostem tissue as the major chemical cue when searching for prey.


Asunto(s)
Escarabajos/fisiología , Conducta Alimentaria , Musa/parasitología , Aceites Volátiles/farmacología , Nervio Olfatorio/efectos de los fármacos , Feromonas/farmacología , Animales , Interacciones Huésped-Parásitos
15.
Bull Entomol Res ; 95(3): 231-41, 2005 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-15960877

RESUMEN

Host finding and parasitization by Uscana lariophaga Steffan, a potential biocontrol agent of the storage pest Callosobruchus maculatus (Fabricius), were investigated in stored cowpea. Host finding was shown to be a function of distance, time, host patch size and the spatial position of U. lariophaga relative to the host patch. Uscana lariophaga females were able to find hosts up to 75 cm horizontal distance from the host patch, which was the largest distance tested. The probability that a host patch was found when an individual U. lariophaga female was released at 2.5 cm horizontal distance from the host patch ranged from 0.6 after 2 h foraging time to 0.9 after 8 h foraging time. At 10 cm from the host patch, host finding probability ranged from 0.2 to 0.45 at these respective foraging times. Finding probabilities doubled compared to horizontal distances when U. lariophaga was released below the host patch, and halved when it was released above the host patch. The negative geotaxic response was shown not to be an artefact of the release method. The median net displacement rate in the direction of the host patch was two beans per hour (1.4 cm h(-1)). The results suggest that U. lariophaga females start searching for hosts regardless of the quality of the olfactory information they receive. Additional observations indicated that U. lariophaga is adapted to a host with a patchy distribution, which implies that host finding over larger distances is relevant for U. lariophaga.


Asunto(s)
Escarabajos/parasitología , Conducta Exploratoria/fisiología , Avispas/fisiología , Animales , Demografía , Fabaceae , Interacciones Huésped-Parásitos , Modelos Logísticos , Orientación/fisiología , Estadísticas no Paramétricas , Factores de Tiempo
16.
Annu Rev Entomol ; 45: 631-59, 2000.
Artículo en Inglés | MEDLINE | ID: mdl-10761592

RESUMEN

African agriculture is largely traditional--characterized by a large number of smallholdings of no more than one ha per household. Crop production takes place under extremely variable agro-ecological conditions, with annual rainfall ranging from 250 to 750 mm in the Sahel in the northwest and in the semi-arid east and south, to 1500 to 4000 mm in the forest zones in the central west. Farmers often select well-adapted, stable crop varieties, and cropping systems are such that two or more crops are grown in the same field at the same time. These diverse traditional systems enhance natural enemy abundance and generally keep pest numbers at low levels. Pest management practice in traditional agriculture is a built-in process in the overall crop production system rather than a separate well-defined activity. Increased population pressure and the resulting demand for increased crop production in Africa have necessitated agricultural expansion with the concomitant decline in the overall biodiversity. Increases in plant material movement in turn facilitated the accidental introduction of foreign pests. At present about two dozen arthropod pests, both introduced and native, are recognized as one of the major constraints to agricultural production and productivity in Africa. Although yield losses of 0% to 100% have been observed on-station, the economic significance of the majority of pests under farmers' production conditions is not adequately understood. Economic and social constraints have kept pesticide use in Africa the lowest among all the world regions. The bulk of pesticides are applied mostly against pests of commercial crops such as cotton, vegetables, coffee, and cocoa, and to some extent for combating outbreaks of migratory pests such as the locusts. The majority of African farmers still rely on indigenous pest management approaches to manage pest problems, although many government extension programs encourage the use of pesticides. The current pest management research activities carried out by national or international agricultural research programs in Africa focus on classical biological control and host plant resistance breeding. With the exception of classical biological control of the cassava mealybug, research results have not been widely adopted. This could be due to African farmers facing heterogeneous conditions, not needing fixed prescriptions or one ideal variety but a number of options and genotypes to choose from. Indigenous pest management knowledge is site-specific and should be the basis for developing integrated pest management (IPM) techniques. Farmers often lack the biological and ecological information necessary to develop better pest management through experimentation. Formal research should be instrumental in providing the input necessary to facilitate participatory technology development such as that done by Farmer Field Schools, an approach now emerging in different parts of Africa.


Asunto(s)
Control de Insectos/métodos , África , Agricultura , Animales , Artrópodos , Ecosistema , Humanos , Plaguicidas
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