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The rearing of fall armyworm, Spodoptera frugiperda larvae in cohorts is usually associated with high levels of cannibalism-induced mortalities especially in the later instar larvae. To avoid this problem, rearing is done using an individual-based method that often requires relatively more man-hours, man power and laboratory space. To substantially reduce cannibalism-induced mortalities in cohort-based laboratory cultures of S. frugiperda, the primary factors influencing intra-instar cannibalism must be properly elucidated. In this study, the effect of food quantity, number of larvae reared (larval population density) and size of rearing container on cannibalism-induced mortalities was investigated at the fifth, early sixth and late sixth (fully mature) instar stages of S. frugiperda. Results showed that at each instar stage, larval population density rather than food quantity, significantly (p < 0.0001) influenced cannibalism-induced mortalities. In addition, no significant interactions (p > 0.11) were observed between both factors. At the late sixth instar, the highest cannibalism-induced mortality (74.67%) occurred when 15-larvae fed only two grams of food were reared together. However, when food quantity increased to five grams, observed mortality was 52.00%. While higher mortalities were generally observed in small rearing containers, the size of larval-rearing container was not a significant (p = 0.01) factor influencing cannibalism-induced mortalities at the three instar stages. The foregoing suggests that while food quantity may not be the most important factor influencing intra-instar cannibalism in S. frugiperda, it nonetheless plays a synergistic role with the number of larvae being reared, and is more important than the size of rearing container. [ABSTRACT FROM AUTHOR]

Abstract The fall armyworm, Spodoptera frugiperda J.E Smith, is a highly destructive insect pest of maize that first invaded Africa in 2016 and has since posed additional constraints to maize production and food security in the region. This study thus investigated the seasonal difference in the abundance of S. frugiperda egg masses and larvae on 25 maize varieties during the early and late planting seasons of 2018 and 2019 in Ibadan, southwest Nigeria. The relationship between larva abundance and foliar damage was also investigated at three-, five- and seven weeks after planting (3WAP, 5WAP, and 7WAP). Results showed that abundance was higher in 2018, in the early season, and at 3WAP. Though foliar damage occurred weekly in both seasons, the relationship between foliar damage severity and larva abundance at 7WAP was consistently weak and insignificant. Also, in both seasons, most of the observed kernel damage was caused by stem borer and not fall armyworm larvae. To make timely fall armyworm management decisions, regular field scouting, especially within the first three weeks after planting, is recommended. [ABSTRACT FROM AUTHOR]

Detailed information on insect pests of stored grains in Nigeria is lacking. A two-year survey was conducted to determine the species composition and abundance of insects associated with maize, millet, rice, sorghum and tamarind in eighteen locations across five agro-ecological zones in Nigeria. Sixteen coleopteran, lepidopteran and hymenopteran species were associated with stored products, with high species richness on cereal grains but low species richness on tamarind. Most of these insects are polyphagous on cereal grains, whereas the tamarind weevil Sitophilus linearis (Herbst, 1797) (Curculionidae), and Caryedon serratus (Oliver, 1790) (Chrysomelidae) were found only on tamarind in this study. The maize weevil Sitophilus zeamais (Motschulsky, 1758), rice weevil Sitophilus oryzae (Linneaus, 1763), lesser grain borer Rhyzopertha dominica (Fabricius, 1792) (Bostrichidae), rusty grain beetle Cryptolestes ferrugineus (Stephens, 1831) (Laemophloeidae) and red flour beetle Tribolium castaneum (Herbst, 1797) (Tenebrionidae) were most abundant on stored grains. The tamarind weevil, C. serratus and the sawtoothed grain beetle Oryzaephilus surinamensis (Linneaus, 1758) (Silvanidae) were most abundant on tamarind. The hymenopterans Theocolax elegans (Westwood, 1874) (Pteromalidae), Anisopteromalus calandrae (Howard, 1881) (Pteromalidae) and Cephalonomia waterstoni (Gahan, 1931) (Bethylidae) were the dominant parasitoids of larvae and pupae of the storage pests. Simpson index of diversity of insect species across locations ranged from low (0.63) to high (0.89). [ABSTRACT FROM AUTHOR]

The article focuses on a study which investigated the mass culture of the maize weevil Sitophilus zeamais that were fed on an artificial maize-cassava diet. The artificial diet utilized in the study was compounded from different proportions of maize variety TZPB-SW-R, cassava variety TMS-2110, and amino acid supplements. The study described the mineral and vitamin composition of artificial diet pellets.

There has been no previous systematic, epidemiological study of the reproductive risk factors for uterine fibroids (UF) in African populations despite African women having the highest burden of UF in the world. Improved knowledge of the associations between UF and reproductive factors would contribute to better understanding of the etiology of UF and may suggest novel opportunities for prevention and therapeutic interventions. We used nurse administered questionnaires to survey the demographic and reproductive risk factors of UF among 484 women who are members of the African Collaborative Center for Microbiome and Genomics Research (ACCME) Study Cohort in central Nigeria, and who had transvaginal ultrasound diagnosis (TVUS). We used logistic regression models to the evaluate associations between reproductive risk factors and UF, adjusted for significant covariates. In our multivariable logistic regression models, we found inverse associations with number of children (OR = 0.83, 95%CI = 0.74–0.93, p-value = 0.002), parity (OR = 0.41, 95%CI = 0.24–0.73, p-value = 0.002), history of any type of abortion (OR = 0.53, 95%CI = 0.35–0.82, p-value = 0.004), duration of use of Depot Medroxyprogesterone Acetate (DMPA) (p-value for trend = 0.02), menopausal status (OR = 0.48, 95%CI = 0.27–0.84, p-value = 0.01), and a non-linear positive association with age (OR = 1.04, 95%CI = 1.01–1.07, p-value = 0.003). Other reproductive risk factors that have been reported in other populations (age at menarche and menopause, and oral contraceptives) were not associated with UF in this study. Our study confirms some of the reproductive risk factors for UF that have been found in other populations and shows that some of them are stronger in the Nigerian population. The associations we found with DMPA suggest opportunities for further research to understand the mechanisms of action of progesterone and its analogues in the etiology of UF, their potential use for prevention and treatment of UF. [ABSTRACT FROM AUTHOR]

Self-report of uterine fibroids (UF) has been used for epidemiologic research in different environments. Given the dearth of studies on the epidemiology of UF in Sub-Saharan Africa (SSA), it is valuable to evaluate its performance as a potential tool for much needed research on this common neoplasm in SSA women. We conducted a cross-sectional study of self-report of UF compared with transvaginal ultrasound diagnosis (TVUS) among 486 women who are members of the African Collaborative Center for Microbiome and Genomics Research (ACCME) Study Cohort in central Nigeria. We used log-binomial regression models to compute the classification, sensitivity, specificity, and predictive values of self-report compared to TVUS, adjusted for significant covariates. The prevalence of UF on TVUS was 45.1% (219/486) compared to 5.4% (26/486) based on self-report of abdominal ultrasound scan and 7.2% (35/486) based on report of healthcare practitioner's diagnosis. Self-report correctly classified 39.5% of the women compared to TVUS in multivariable adjusted models. The multivariable adjusted sensitivity of self-report of healthcare worker diagnosis was 38.8%, specificity was 74.5%, positive predictive value (PPV) was 55.6%, and negative predictive value (NPV) was 59.8%. For self-reported abdominal ultrasound diagnosis, the multivariable adjusted sensitivity was 40.6%, specificity was 75.3%, PPV was 57.4%, and NPV was 60.6%. Self-report significantly underestimates the prevalence of UF and is not accurate enough for epidemiological research on UF. Future studies of UF should use population-based designs and more accurate diagnostic tools such as TVUS. [ABSTRACT FROM AUTHOR]

Background: Escalation in the global rates of labour interventions, particularly cesarean section and oxytocin augmentation, has renewed interest in a better understanding of natural labour progression. Methodological advancements in statistical and computational techniques addressing the limitations of pioneer studies have led to novel findings and triggered a re-evaluation of current labour practices. As part of the World Health Organization's Better Outcomes in Labour Difficulty (BOLD) project, which aimed to develop a new labour monitoring-to-action tool, we examined the patterns of labour progression as depicted by cervical dilatation over time in a cohort of women in Nigeria and Uganda who gave birth vaginally following a spontaneous labour onset.Methods and Findings: This was a prospective, multicentre, cohort study of 5,606 women with singleton, vertex, term gestation who presented at ≤ 6 cm of cervical dilatation following a spontaneous labour onset that resulted in a vaginal birth with no adverse birth outcomes in 13 hospitals across Nigeria and Uganda. We independently applied survival analysis and multistate Markov models to estimate the duration of labour centimetre by centimetre until 10 cm and the cumulative duration of labour from the cervical dilatation at admission through 10 cm. Multistate Markov and nonlinear mixed models were separately used to construct average labour curves. All analyses were conducted according to three parity groups: parity = 0 (n = 2,166), parity = 1 (n = 1,488), and parity = 2+ (n = 1,952). We performed sensitivity analyses to assess the impact of oxytocin augmentation on labour progression by re-examining the progression patterns after excluding women with augmented labours. Labour was augmented with oxytocin in 40% of nulliparous and 28% of multiparous women. The median time to advance by 1 cm exceeded 1 hour until 5 cm was reached in both nulliparous and multiparous women. Based on a 95th percentile threshold, nulliparous women may take up to 7 hours to progress from 4 to 5 cm and over 3 hours to progress from 5 to 6 cm. Median cumulative duration of labour indicates that nulliparous women admitted at 4 cm, 5 cm, and 6 cm reached 10 cm within an expected time frame if the dilatation rate was ≥ 1 cm/hour, but their corresponding 95th percentiles show that labour could last up to 14, 11, and 9 hours, respectively. Substantial differences exist between actual plots of labour progression of individual women and the 'average labour curves' derived from study population-level data. Exclusion of women with augmented labours from the study population resulted in slightly faster labour progression patterns.Conclusions: Cervical dilatation during labour in the slowest-yet-normal women can progress more slowly than the widely accepted benchmark of 1 cm/hour, irrespective of parity. Interventions to expedite labour to conform to a cervical dilatation threshold of 1 cm/hour may be inappropriate, especially when applied before 5 cm in nulliparous and multiparous women. Averaged labour curves may not truly reflect the variability associated with labour progression, and their use for decision-making in labour management should be de-emphasized. [ABSTRACT FROM AUTHOR]

Objective: "Negotiated standards" describe a level of quality of care that is acceptable and achievable within a specific health system, based on consensus between key stakeholders. This paper presents the development of negotiated standards for effective labor and childbirth care in selected hospitals and communities in Nigeria and Uganda.Methods: A four-step development process involving different methodologies. The process included: (1) review and synthesis of internationally recognized intrapartum clinical principles and practices; (2) primary qualitative research to assess values and preferences of women and healthcare providers, and practices that align with these preferences; (3) draft contextualization of effective and ineffective behaviors to reflect values and preferences; and (4) WHO-mediated negotiations between relevant stakeholders, including community members, providers, and administrators.Results: The primary outcomes of this process were a comprehensive set of effective behaviors and clinical practices covering the main domains of quality of care, which are practical and easy to communicate, implement, and audit across all levels of healthcare delivery.Conclusion: The process demonstrates that health facilities and providers can be motivated to adopt standards of care that uphold the values and preferences of both service users and providers, while adhering to international best practices. [ABSTRACT FROM AUTHOR]

Objective: To determine risk factors for perinatal mortality among hospital-based deliveries in Nigeria.Methods: The WHO Global Maternal and Perinatal Health Survey was implemented in Nigeria as a first step in establishing a global system for monitoring maternal and perinatal health. Twenty-one health facilities with more than 1000 deliveries annually were selected by a stratified multistage cluster sampling strategy. Information was recorded on all women who delivered and their neonates within a 3-month period.Results: Overall, there were 9208 deliveries, comprising 8526 live births, 369 fresh stillbirths, 282 macerated stillbirths, 70 early neonatal deaths, and 721 perinatal deaths. The stillbirth and perinatal mortality rates were, respectively, 71 and 78 per 1000 deliveries; the early neonatal death rate was 8 per 1000 live births. Approximately 10% of all newborns weighed less than 2500 g, and 12.3% were born at less than 37 weeks of gestation. Predictors of perinatal mortality were mother's age, lack of prenatal care, unbooked status, prematurity, and birth asphyxia.Conclusion: The perinatal mortality rate remains unacceptably high in Nigeria. Fresh stillbirth accounted for most perinatal deaths. Interventions to improve the utilization and quality of prenatal care, in addition to the quality of intrapartum care, would considerably reduce perinatal death. [ABSTRACT FROM AUTHOR]