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

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

Genetic parameters and genomic regions associated with growth rate and response to Newcastle disease in local chicken ecotypes in Ghana and Tanzania

Local chicken breeds play an important role in the livelihoods of people in both rural and urban areas of Africa. One of the main constraints to the poultry sector in many sub-Saharan countries is disease, with Newcastle disease (ND) being the most important. Because vaccination does not adequately control ND, selective breeding offers an effective complement, provided there is genetic variation in resistance, tolerance and/or response to ND. We investigated this topic by challenging 6 local ecotypes from Ghana and Tanzania with a lentogenic (vaccine) strain of Newcastle disease virus (NDV), then measuring growth, anti-NDV antibody levels, and viral load from hatch to 38 days of age. We estimated variance components and performed a genome-wide association study using 2800 birds genotyped with the 600K Affymetrix chicken genotyping array. Heritabilities were moderate to high (0.14 – 0.55) for all the traits studied, which indicates that selection to improve these breeds for resistance to ND can be feasible. GWAS also revealed several genomic regions that explained ≥0.5% of the genetic variance, including a candidate gene region for antibody response on GGA1. We conclude that all traits investigated in this study appear to be highly polygenic in nature. Future studies will characterize differences between the breeds/ecotypes, determine if large breed-specific quantitative trait loci can be identified, and evaluate the response of the same birds to endemic, velogenic NDV strains

Investigation of Genetic Resistance to Newcastle Disease in Local Chickens in Tanzania using Natural Challenge by Field Velogenic NDV Strains

Genetic resistance to Newcastle disease among three ecotypes of Tanzanian local chickens, Ching’wekwe, Kuchi and Morogoro MEDIUM was investigated by natural challenge with endemic velogenic strains of Newcastle disease virus (vNDV). The study was designed to determine variations in susceptibility and response to NDV among the three ecotypes. Naturally NDV-infected seeders were introduced into flocks of susceptible chickens under a controlled environment. For each bird, body weights were measured at 0, 7, 9, 11, 13, 15, 17, and 25 days post-exposure. Flock mortality was assessed every 8 hours for the first three days and then every 12 hours thereafter until 29 days post-exposure. Date and time of death was recorded, and post-mortem examinations performed for each dead chicken. Lesions on the trachea, proventriculus, intestines, and caecal tonsils were scored for severity ranging from 0 to 3. Linear models were used for survival days, post-exposure growth rate and average lesion score. Preliminary results indicate that post-exposure weight reduction in Ching’wekwe was significantly less than in Morogoro Medium and Kuchi. No significant differences were observed in the lesion scores and survival times among the three ecotypes after exposure. More data is being collected for more comprehensive analysis

Phenotypic and genotypic diversity of selected Free Range Local Chickens in Tanzania

Free range local chickens are an important source of protein as meat and eggs in Tanzania. Few studies have been done to improve their productivity. To this end, this paper focuses on characterizing three common Tanzanian local chicken ecotypes. Morphologic and genetic diversity studies show that the Kuchi have relatively higher body dimension measures than Ching’wekwe and Morogoro medium and that the Ching’wekwe ecotype is genetically more related to Morogoro medium than to the Kuchi ecotype. These differences indicate variation in traits that call for further research and opportunities to improve productivity of free range local chickens

Molecular characterization of Newcastle disease virus obtained from Mawenzi live bird market in Morogoro, Tanzania in 2020–2021

DATA AVAILABLILITY : All the data generated during this study are included in this manuscript.Newcastle disease (ND) is among the most important poultry diseases worldwide. It is the major threat to poultry production in Africa and causes major economic losses for both local and commercial chickens. To date, half of ND class II genotypes have been reported in Africa (I, IV, V, VI, VII, XI, XIII, XIV, XVII, XVIII, and XXI). The information on the circulating NDV genotypes is still scarce despite the endemic nature of ND in most countries on the African continent.A total of 659 oro-cloacal swabs were collected from local chickens in Mawenzi live bird market located in Morogoro, Tanzania, between June 2020 and May 2021. Newcastle disease virus was detected by using reverse transcription real-time polymerase chain reaction (RT-qPCR) and conventional PCR followed by sequencing of PCR products. The prevalence of NDV in the surveilled live bird markets was 23.5%. Sequencing and phylogenetic analysis revealed the presence of sub-genotype VII.2. The detected sub-genotype VII.2 has phylogenetic links to Zambian NDV strains implying a Southeast dissemination of the virus, considering that it was first detected in Mozambique. This study underscores the need of active NDV surveillance to determine the distribution of this NDV genotype in the country and monitor its spread and contribution to the emergence of new ND viruses.The American people through the United States Agency for International Development (USAID) Feed the Future Innovation Lab for Genomics to Improve Poultry. The RT-qPCR screening and Ion Torrent sequencing was provided by the South African National Research Foundation (NRF)/Department of Science and Innovation (DSI).https://link.springer.com/journal/42770am2024Production Animal StudiesSDG-02:Zero HungerSDG-03:Good heatlh and well-bein

Prevalence and antibiotic susceptibility of thermophilic Campylobacter isolates from free range domestic duck (Cairina moschata) in Morogoro municipality, Tanzania

Tropical animal health production June 2009Prevalence and antibiotic susceptibility of thermophilic Campylobacter isolated from freeranging ducks was determined in Morogoro Municipality, Tanzania. Ninety intestinal contents from ducks were screened for thermophilic Campylobacter using Skirrow’s protocol. Of the Campylobacter jejuni isolates, 50 were tested for sensitivity to 12 antibiotics. Overall prevalence of thermophilic Campylobacter was 80%. The prevalence of Campylobacter in adult ducks (91.3%) was significantly (p<0.05) higher than ducklings (68.2%). The isolation rate of C. jejuni (81.9%) was significantly (P<0.001) higher than C. coli (18.1%). All C. jejuni isolates were susceptible to streptomycin, nitrofurantoin and amikacin. Forty eight percent, 74% and 82% of isolates were resistant to cefuroxime sodium, tetracycline and ampicillin respectively. Between 20–50% of isolates were resistant to erythromycin, gentamicin, cloxacillin and amoxicillin. Norfloxacin and ciprofloxacin had lower C. jejuni resistance of 10% and 16% respectively. C. jejuni isolates from adult ducks showed significantly higher rates of resistance (p< 0.05) to most antibiotics than did duckling isolates.High prevalence of thermophilic Campylobacter in ducks could be of public health significance in Morogoro municipality. The observed multidrug resistance in this study poses a threat of transfer of antibiotic resistance to human pathogens because of the close contact between ducks and human

Prevalence and antibiotic susceptibility of thermophilic Campylobacter isolates from free range domestic duck (Cairina moschata) in Morogoro municipality, Tanzania

Tropical animal health production June 2009Prevalence and antibiotic susceptibility of thermophilic Campylobacter isolated from freeranging ducks was determined in Morogoro Municipality, Tanzania. Ninety intestinal contents from ducks were screened for thermophilic Campylobacter using Skirrow’s protocol. Of the Campylobacter jejuni isolates, 50 were tested for sensitivity to 12 antibiotics. Overall prevalence of thermophilic Campylobacter was 80%. The prevalence of Campylobacter in adult ducks (91.3%) was significantly (p<0.05) higher than ducklings (68.2%). The isolation rate of C. jejuni (81.9%) was significantly (P<0.001) higher than C. coli (18.1%). All C. jejuni isolates were susceptible to streptomycin, nitrofurantoin and amikacin. Forty eight percent, 74% and 82% of isolates were resistant to cefuroxime sodium, tetracycline and ampicillin respectively. Between 20–50% of isolates were resistant to erythromycin, gentamicin, cloxacillin and amoxicillin. Norfloxacin and ciprofloxacin had lower C. jejuni resistance of 10% and 16% respectively. C. jejuni isolates from adult ducks showed significantly higher rates of resistance (p< 0.05) to most antibiotics than did duckling isolates.High prevalence of thermophilic Campylobacter in ducks could be of public health significance in Morogoro municipality. The observed multidrug resistance in this study poses a threat of transfer of antibiotic resistance to human pathogens because of the close contact between ducks and human