Financial impact of an outbreak of clinically diagnosed blackleg – a case study from Lao PDR

Abstract

Blackleg ( BL ) is an acute to peracute highly fatal infectious disease of mainly large ruminants characterised by lesions of myonecrosis caused by Clostridium chauvoei, usually presenting as a sudden onset of sporadic mortalities. In Southeast Asia, ‘ BL ’ is considered a cause of occasional outbreaks of a subacute febrile illness, although there are few published reports available. Investigation of a major outbreak of clinically diagnosed BL occurring in large ruminants (cattle and buffalo) in three neighbouring villages in central Laos in mid‐2017, was conducted to determine the financial impacts of BL on smallholder livelihoods. Owners of BL ‐infected large ruminants in the three affected villages were interviewed ( n = 27) and financial losses including losses due to mortality, morbidity and costs of treatments, were determined. The reports of clinical signs of subcutaneous swelling with palpable crepitus in febrile animals were considered consistent with a diagnosis of BL . The outbreak occurred in 47 of a total 449 households with large ruminants across the three villages, affecting 147 of a total population of 3505 ‘at risk’ large ruminants with 71 deaths reported. At the household level, the mean morbidity and mortality rates were 5 ± 4(95% CI : 3–6) and 3 ± 2(95% CI : 1–4) heads per household, respectively. The estimated financial losses due to BL per affected household was USD 822 ± 692(95% CI : 518–1125), being 122% of their annual household income from large ruminant sales. The comparison between the estimated losses due to BL per village and cost of annual BL vaccination programmes, indicated a potential economic benefit of USD 3.09 and USD 12.37 for every dollar invested in the vaccination programme, if BL outbreaks occur every 20 and 5 years, respectively. This study indicates that clinically diagnosed BL can cause significant losses to smallholder households, and requires Lao animal health authorities to consider vaccination interventions to prevent losses from re‐emergence of BL in the known endemically affected areas.

Improved Milk Production from Supplementation of Swamp Buffalo with Molasses Nutrient Blocks Containing 10% Urea

“…Increasing demand for buffalo meat and more recently milk in both domestic and neighbouring markets offers important opportunities for smallholders to gain more income from their buffalo, enhancing food security and reducing rural poverty. However, improving buffalo production requires numerous constraints to be addressed, including nutritional deficits; low reproductive performance and presence of reproductive pathogens; high slaughter rates of pregnant cows; undeveloped trade and marketing systems; limited veterinary and extension service capacity, health issues, including parasitism (particularly Toxocara vitulorum), endemic diseases (particularly haemorrhagic septicaemia (HS) and in some locations blackleg control), and transboundary diseases, especially foot and mouth disease (FMD) due to poor biosecurity controls, and potentially, climate change and policy impacts [6][7][8].…”

<p>Managing Welfare and Antimicrobial-Resistance Issues in Treating Foot-and-Mouth Disease Lesions: A New Therapeutic Approach</p>

“…Although the isolates from Luang Prabang in 2019 remain untyped, it is presumed they are PanAsia topotype, as this was the predominant serotype circulating in the region at that time. 1,17 The challenge of achieving laboratory confirmation of outbreaks of disease in developing countries where veterinary services remain underresourced is well recognized, with priorities directed to large-scale projects externally funded by international donor agencies. Previous experience in Mekong countries has required that important field observations based on detailed clinical observations of disease outbreaks, including blackleg in Laos, 18 and hemorrhagic septicemia in Cambodia, 19 be successfully reported in the literature, despite the absence of laboratory confirmation due to the numerous challenges in achieving otherwise-routine analyses.…”

Is Improved Milk Production from Supplementation of Buffalo with Molasses Nutrient Blocks Containing 10% Urea, a Greenhouse Gas Emissions Mitigation Strategy?

“…There is also enormous potential for improved rural smallholder livelihoods from milk production from buffalo, particularly in countries such as Laos where there has been limited supply and use of milk, despite a clear need for increased ASF to improve childhood nutrition. However, for smallholders to exploit these opportunities, there are many challenges that need to be addressed [6,8,25]. Most livestock farmers in developing countries have low animal husbandry skills, minimal nutritional, biosecurity, animal disease and reproductive management knowledge, poor access to markets, and high rates of illiteracy.…”

“…These dry season ADGs were considerably lower than both the early and late wet season ADGs of 223 to 282g/day and ADGs of 123 to 247g/day in buffalo, respectively [6]. Decreased animal condition in the dry season has implications for on-farm production efficiency and profitability, with post-partum anoestrus contributing to extended inter-calving intervals, estimated at 19-26 months in buffalo [6,8,11].…”

“…The total meat consumption in Laos and China was approximately 21 kg and 58 kg per capita in 2009, with an annual growth rate forecast of 4.5% and 3.1% [6] Increasing demand for buffalo meat and more recently milk in both domestic and neighbouring markets offers important opportunities for smallholders to gain more income from their buffalo, enhancing food security and reducing rural poverty. However, improving buffalo production requires numerous constraints to be addressed, including: nutritional deficits; low reproductive performance and presence of reproductive pathogens; high slaughter rates of pregnant cows; undeveloped trade and marketing systems, limited veterinary and extension service capacity, health issues, including parasitism (particularly Toxocara vitulorum), endemic diseases (particularly haemorrhagic septicaemia (HS) and in some locations blackleg control), and transboundary diseases, especially foot and mouth disease (FMD) due to poor biosecurity controls and potentially, climate change and policy impacts [6,7,8].…”