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Featured researches published by David A. Bunn.


Nutrition Reviews | 2014

Eggs: the uncracked potential for improving maternal and young child nutrition among the world's poor

Lora Iannotti; Chessa K. Lutter; David A. Bunn; Christine P. Stewart

Eggs have been consumed throughout human history, though the full potential of this nutritionally complete food has yet to be realized in many resource-poor settings around the world. Eggs provide essential fatty acids, proteins, choline, vitamins A and B12 , selenium, and other critical nutrients at levels above or comparable to those found in other animal-source foods, but they are relatively more affordable. Cultural beliefs about the digestibility and cleanliness of eggs, as well as environmental concerns arising from hygiene practices and toxin exposures, remain as barriers to widespread egg consumption. There is also regional variability in egg intake levels. In Latin American countries, on average, greater proportions of young children consume eggs than in Asian or African countries. In China and Indonesia, nutrition education and social marketing have been associated with greater amounts of eggs in the diets of young children, though generally, evidence from interventions is minimal. Homestead chicken-and-egg production with appropriate vaccination, extension service, and other supports can simultaneously address poverty and nutrition in very poor rural households. With undernutrition remaining a significant problem in many parts of the world, eggs may be an uncracked part of the solution.


Tropical Animal Health and Production | 2010

Implementing poultry vaccination and biosecurity at the village level in Tanzania: a social strategy to promote health in free-range poultry populations

David A. Bunn; Amandus P. Muhairwa; M.M.A. Mtambo; H. Mwamhehe; Ayubu Omari Msago; M. R. S. Mlozi; Carol J. Cardona

A social strategy was tested for implementing Newcastle disease (ND) vaccination and biosecurity improvements among free-ranging chicken at village level in Tanzania. In addition to training the local poultry vaccinators, data recorders and poultry-keepers, the strategy involved training and empowering leaders at the district, ward and village level. The trainings covered poultry health, management, and marketing of village chickens, with an emphasis on ND vaccination and improving biosecurity against avian influenza (AI), The study sites included villages in one ward in each of three each three districts (Iringa, Mtwara-Mikindani, and Mvomero) of mainland Tanzania. Ninety-six local leaders at district level and 101 leaders at ward levels were trained. In addition, 196 farmers (households) were trained, as well as 86 vaccinators and 26 data recorders. Data recorders were also trained as poultry first aid workers. ND vaccination was conducted by the vaccinators, supervised by their local leaders with technical assistance from veterinarians. A total of 158,343 village chickens were vaccinated in three rounds of vaccination three months apart. The training and empowerment of local leaders and local implementers was the key element for success as it fostered the feeling of local ownership of the program and prevented conflicts with other development activities within the villages. We conclude that most animal health programs will increase their odds of success by involving local leaders and by addressing the current challenges facing the farmers. Further assessment on the usefulness of this approach is needed.


Scientific Reports | 2013

Modeling highly pathogenic avian influenza transmission in wild birds and poultry in West Bengal, India.

Pranav Pandit; David A. Bunn; Satish Pande; Sharif S. Aly

Wild birds are suspected to have played a role in highly pathogenic avian influenza (HPAI) H5N1 outbreaks in West Bengal. Cluster analysis showed that H5N1 was introduced in West Bengal at least 3 times between 2008 and 2010. We simulated the introduction of H5N1 by wild birds and their contact with poultry through a stochastic continuous-time mathematical model. Results showed that reducing contact between wild birds and domestic poultry, and increasing the culling rate of infected domestic poultry communities will reduce the probability of outbreaks. Poultry communities that shared habitat with wild birds or those indistricts with previous outbreaks were more likely to suffer an outbreak. These results indicate that wild birds can introduce HPAI to domestic poultry and that limiting their contact at shared habitats together with swift culling of infected domestic poultry can greatly reduce the likelihood of HPAI outbreaks.


Clinical and Vaccine Immunology | 2017

Novel mechanisms revealed in the trachea transcriptome of resistant and susceptible chicken lines following infection with Newcastle disease virus

Melissa S. Deist; Rodrigo A. Gallardo; David A. Bunn; Terra R. Kelly; Jack C. M. Dekkers; Huaijun Zhou; Susan J. Lamont

ABSTRACT Newcastle disease virus (NDV) has a devastating impact on poultry production in developing countries. This study examined the transcriptome of tracheal epithelial cells from two inbred chicken lines that differ in NDV susceptibility after challenge with a high-titer inoculum of lentogenic NDV. The Fayoumi line had a significantly lower NDV load postchallenge than the Leghorn line, demonstrating the Fayoumi lines classification as a relatively NDV-resistant breed. Examination of the trachea transcriptome showed a large increase in immune cell infiltration in the trachea in both lines at all times postinfection. The pathways conserved across lines and at all three time points postinfection included iCOS-iCOSL signaling in T helper cells, NF-κB signaling, the role of nuclear factor of activated T cells in the regulation of the immune response, calcium-induced T lymphocyte apoptosis, phospholipase C signaling, and CD28 signaling in T helper cells. Although shared pathways were seen in the Fayoumi and Leghorn lines, each line showed unique responses as well. The downregulation of collagen and the activation of eukaryotic translation initiation factor 2 signaling in the Fayoumis relative to the Leghorns at 2 days postinfection may contribute to the resistance phenotype seen in the Fayoumis. This study provides a further understanding of host-pathogen interactions which could improve vaccine efficacy and, in combination with genome-wide association studies, has the potential to advance strategies for breeding chickens with enhanced resistance to NDV.


Journal of Wildlife Diseases | 2012

HEMATOLOGY AND PLASMA BIOCHEMISTRY VALUES FOR THE GIANT GARTER SNAKE (THAMNOPHIS GIGAS) AND VALLEY GARTER SNAKE (THAMNOPHIS SIRTALIS FITCHI) IN THE CENTRAL VALLEY OF CALIFORNIA

Raymund F. Wack; Eric Hansen; Marilyn Small; Robert H. Poppenga; David A. Bunn; Christine K. Johnson

Hematology and plasma biochemistry parameters are useful in the assessment and management of threatened and endangered species. Although reference ranges are readily available for many mammalian species, reference ranges for snakes are lacking for most species. We determined hematology and plasma biochemistry reference ranges for giant garter snakes (Thamnophis gigas) and valley garter snakes (Thamnophis sirtalis fitchi) living in four management areas in the Central Valley of California. White blood cell, heterophil, lymphocyte, and azurophil counts in giant garter snakes were approximately twice the values of valley garter snakes. Statistically significant differences in aspartate aminotransferase, globulin, and potassium between the two species did not appear clinically significant. No significant differences were found in the measured parameters between male and female giant garter snakes. Some differences were found among collection sites. These reference ranges provide baseline data for comparisons over time and between collection sites.


Avian Diseases | 2010

Detection and Prevention of Highly Pathogenic Avian Influenza in Communities with High Poultry Disease Burdens

Carol J. Cardona; Denis K. Byarugaba; P G Mbuthia; George Aning; Sabi Sourou; David A. Bunn

Abstract The implementation of strategies to detect, prevent, and control highly pathogenic avian influenza (HPAI) in developing countries presents several challenges, one of which is the presence of other diseases in poultry populations. Training workshops in developing countries using the Avian Flu School have revealed that in areas with heavy Newcastle disease burdens, smallholder poultry keepers do not recognize HPAI as an immediate threat. We have developed a strategy to address the more proximal needs and priorities of communities with free-ranging poultry flocks as a means to create value in poultry, and thus to improve disease detection and prevention overall. To this end, we have created the Poultry Health and Well-Being for Development project, which trains graduate veterinarians and paraprofessionals in poultry disease diagnosis, control, and treatment. These trainees then serve their local communities to improve poultry health and to implement disease detection and management programs.


Avian Diseases | 2010

Preparation for the prevention and control of highly pathogenic avian influenza in rural Tanzanian village settings.

David A. Bunn; Amandus P. Muhairwa; M.M.A. Mtambo; Hamza Mwamhehe; Ayubu Omari Msago; Malongo Mlozi; Carol J. Cardona

Abstract Free-ranging local chicken flocks are important for the livelihood of resource-poor rural farmers in Tanzania, as they provide a critical source of animal protein and a ready source of income through the sale of chickens and eggs. An occurrence of highly pathogenic avian influenza (HPAI) in the village setting of Tanzania would result in a disastrous loss of livelihood. This paper attempts to offer an alternative method for preventing and controlling HPAI in village settings of Tanzania through community-based approaches.


Public Health Reports | 2008

Avian Flu School: A Training Approach to Prepare for H5N1 Highly Pathogenic Avian Influenza

Daniel Beltrán-Alcrudo; David A. Bunn; Christian Sandrock; Carol J. Cardona

Since the reemergence of highly pathogenic avian influenza (H5N1 HPAI) in 2003, a panzootic that is historically unprecedented in the number of infected flocks, geographic spread, and economic consequences for agriculture has developed. The epidemic has affected a wide range of birds and mammals, including humans. The ineffective management of outbreaks, mainly due to a lack of knowledge among those involved in detection, prevention, and response, points to the need for training on H5N1 HPAI. The main challenges are the multidisciplinary approach required, the lack of experts, the need to train at all levels, and the diversity of outbreak scenarios. Avian Flu School addresses these challenges through a three-level train-the-trainer program intended to minimize the health and economic impacts of H5N1 HPAI by improving a communitys ability to prevent and respond, while protecting themselves and others. The course teaches need-to-know facts using highly flexible, interactive, and relevant materials.


Preventive Veterinary Medicine | 2011

Integrating surveillance and biosecurity activities to achieve efficiencies in national avian influenza programs

David A. Bunn; Daniel Beltrán-Alcrudo; Carol J. Cardona

Based on the HPAI experience, efforts to improve global capacity to prevent and control zoonotic diseases should consider new and more efficient models for integrating prevention and surveillance activities.


Scientific Reports | 2018

Novel analysis of the Harderian gland transcriptome response to Newcastle disease virus in two inbred chicken lines

Melissa S. Deist; Rodrigo A. Gallardo; David A. Bunn; Terra R. Kelly; Jack C. M. Dekkers; Huaijun Zhou; Susan J. Lamont

Behind each eye of the chicken resides a unique lymph tissue, the Harderian gland, for which RNA sequencing (RNA-seq) analysis is novel. We characterized the response of this tissue to Newcastle disease virus (NDV) in two inbred lines with different susceptibility to NDV across three time points. Three-week-old relatively resistant (Fayoumi) and relatively susceptible (Leghorn) birds were inoculated with a high-titered (107EID50) La Sota strain of NDV via an oculonasal route. At 2, 6, and 10 days post infection (dpi) Harderian glands were collected and analyzed via RNA-seq. The Fayoumi had significantly more detectable viral transcripts in the Harderian gland at 2 dpi than the Leghorn, but cleared the virus by 6 dpi. At all three time points, few genes were declared differentially expressed (DE) between the challenged and nonchallenged birds, except for the Leghorns at 6 dpi, and these DE genes were predicted to activate an adaptive immune response. Relative to the Leghorn, the Fayoumi was predicted to activate more immune pathways in both challenged and nonchallenged birds suggesting a more elevated immune system in the Fayoumis under homeostatic conditions. Overall, this study helped characterize the function of this important tissue and its response to NDV.

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Huaijun Zhou

University of California

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Terra R. Kelly

University of California

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