Edited by: Julio Alvarez, Visavet Health Surveillance Centre (UCM), Spain
Reviewed by: Kimberly VanderWaal, University of Minnesota Twin Cities, United States; Hans-Hermann Thulke, Helmholtz Centre for Environmental Research (UFZ), Germany
This article was submitted to Veterinary Epidemiology and Economics, a section of the journal Frontiers in Veterinary Science
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Live animal markets are common hotspots for the dispersal of multiple infectious diseases in various production systems globally. In Cameroon livestock trade occurs predominantly via a system of livestock markets. Improving the understanding of the risks associated with livestock trade systems and markets is, therefore, key to design targeted and evidence-based interventions. In the current study, official transaction records for a 12-month period were collected from 62 livestock markets across Central and Southern Cameroon, in combination with a questionnaire-based survey with the livestock markets stakeholders. The available information collected at these markets was used to characterize their structural and functional organization. Based on trade volume, cattle price and the intensity of stakeholder attendance, four main classes of livestock markets were identified. Despite an evident hierarchical structure of the system, a relatively limited pool of infectious diseases was consistently reported as predominant across market classes, highlighting homogeneous disease risks along the livestock supply chain. Conversely, the variable livestock management practices reported (e.g., traded species, husbandry practices, and transhumance habits) highlighted diverse potential risks for disease dissemination among market classes. Making use of readily available commercial information at livestock markets, this study describes a rapid approach for market characterization and classification. Simultaneously, this study identifies primary diseases and management practices at risk and provides the opportunity to inform evidence-based and strategic communication, surveillance and control approaches aiming at mitigating these risks for diseases dissemination through the livestock supply chain in Cameroon.
Trade of live animals is a major component of the agricultural sector in sub-Saharan Africa (SSA) (
Live animal markets along the livestock value chain are trading sites where various economic agents (e.g., individuals or businesses) actively interact and negotiate (
Livestock markets in diverse farming systems globally, represent hotspots for the transmission and dispersal of multiple infectious diseases and can play critical roles in epidemic outbreaks (
In this study we analyzed two datasets collected in the Soudano-Sahelian areas of Cameroon from some of the main livestock production regions of the country, where ruminants are by far the most widespread livestock (
The main objectives of this study were (1) to uncover the structural and functional organization of live animal markets, (2) to identify the predominant diseases as reported by livestock stakeholders and (3) to characterize the key trading and management practices at risk for disease spread. An increased knowledge and understanding of markets structure, diseases of primary concern and key management practices will provide evidence to better inform and support the Veterinary Authorities in the conception and design of targeted interventions to improve animal health management along the livestock value chain.
Live animal markets in major livestock production and consumption areas of Cameroon were included in the study. These markets were located mainly across the production areas of the West, North-West and Adamawa Regions but also included markets in densely human populated and high consumption areas in the Central, Litoral and South Regions of the country (
Study area and market locations. The Regions where the data collection was conducted are highlighted in yellow. The location of individual livestock markets visited between September 2014 and May 2015 are indicated by red dots.
The data collection, was carried out between September 2014 and May 2015 at all the livestock markets trading large and small ruminants and listed in the registers obtained from the relevant Regional Delegation of the Ministry of Livestock, Fisheries and Animal Industries (MINEPIA) in the West, North-West and Adamawa Regions of Cameroon (
At each of the 62 markets semi-structured interviews were carried out with the relevant veterinary officer, and with the other stakeholders engaged in the trading activities (herders, traders and butchers). In Cameroon, at the time of the study, details of cattle transactions carried out at markets were handwritten on paper. Simultaneously to the questionnaire-based survey, these trade records at each of these markets were scanned and all cattle transaction data recorded in these official records was extracted for a 12-month period from September 2013 to August 2014.
The administered questionnaires investigated livestock species traded at the market, diseases affecting the traded small and large ruminants and livestock management practices (e.g., number of traded or unsold cattle, the time between purchase of the animal at the market place and the introduction in the new herd, transhumance habits). The eligible population consisted of all the stakeholders conducting live animal negotiations at the market place and, therefore, the sampled population included livestock owners, traders, butchers and intermediaries. However, the context of the livestock markets, where various stakeholders are actively and intensely engaged in negotiations and transactions did not allow for selection of respondents based on representative/random sampling. The survey was, therefore, based on a convenience sampling of livestock markets stakeholders. Each questionnaire-based interview took between 5 and 10 min and was administrated either in French, English or Fufulde depending on the language of the interviewee. Details of the questionnaires used with (i) the veterinary officers and with (ii) the other livestock stakeholders are provided in the
From the 62 markets included in the study, all data related to cattle transactions were extracted from official records for a 12-month period, between September 2013 and August 2014. Market records were scanned using a portable device, archived as
A combination of descriptive analytic approaches was used to characterize the structure and functioning of the livestock marketing system. Temporal trends and variations in the volumes, commercial values as well as the proportions of the type of traded cattle over the 12 months of study were visualized using data from the markets transaction records. This descriptive approach was applied to the data collected through the questionnaire-based survey conducted with the market stakeholders and the relative key livestock management practices.
Groups, or classes, of markets were identified using the 3 key types of information available at the livestock markets. These were (i) the size of the market, given by the total number of traded cattle over a 12-month period, (ii) the mean price of traded cattle over a 12-month period and (iii) the mean number of stakeholders attending a marketing day. The data on the size of the markets and on the mean price per head were obtained from the official documentation, and the information on the number of stakeholders attending the markets (including herders, traders and butchers) from the interviews with the veterinary officer. Clustering was performed combining the 3 information into a unique multidimensional matrix and the Euclidean distance was used to calculate the distance/similarity between the objects/markets. Hierarchical clustering analysis method (
Data processing and analysis was carried out using scripts within the R statistical environment (
Records of a total of 351,345 cattle, traded between the 1st of September 2013 and August the 31st 2014, were collected within the 62 cattle markets across the study area (
Number of cattle markets and number of questionnaires carried out. For each market, one animal health officer representative of the veterinary services was interviewed (
Adamawa | 31 (50.0%) | 332 (55.4%) |
West | 6 (9.8%) | 42 (7.2%) |
North-West | 22 (35.4%) | 196 (32.7%) |
Central | 1 (1.6%) | 10 (1.6%) |
Littoral | 1 (1.6%) | 11 (1.8%) |
South | 1 (1.6%) | 8 (1.3%) |
Total | 62 (100%) | 599 (100%) |
The overall volume of traded cattle and the fluctuation of the mean price per animal across the 12-month period are shown in
Monthly trends of traded cattle and of the mean price per head at markets in the study area. The months of the observation period between September 2013 and August 2014 are displayed on the x axis: yellow bars refer to months during the dry season and blue bars to months during the rainy season.
Four main sub-groups of markets were identified based on the size of the market, given by the total number of traded cattle over a 12-month period, the mean price of traded cattle over a 12-month period and the mean number of stakeholders attending a marketing day (
Classes of cattle markets within the study area. The four major classes of markets identified through hierarchical clustering analysis are highlighted by the four colored quadrants. The classes where named arbitrarily, although taking into consideration the visual details and qualitative and observational information gathered during the inspection at the market sites. The blue quadrant includes “local” markets, the yellow one “sub-regional” markets, the red one “regional” markets and the green one “primary” markets.
Classes of livestock markets across the study area and relative characteristics.
Primary ( |
South | Kye-ossi | 55,836 | 512,000 | 156 |
Central | Yaounde | (9,792–87,347) | (476,000–536,000) | (95–190) | |
Littoral | Douala | ||||
Regional ( |
Adamawa | Ngaoundere, Ngaoundal, Tello, | |||
Banyo, Ngaoui, Likok, Samba | |||||
Mbang Foulbe, Nyambaka | 7,532 | 242,500 | 154 | ||
North-West | Bamenda, Takija | (1,395–19,498) | (202,000–311,000) | (105–223) | |
West | Foumban | ||||
Sub-Regional ( |
Adamawa | Alme, Libong, Dir, Meiganga, | |||
Margol, Mayo Baleo, Dibi, | 2,720 | 220,400 | 87 | ||
Mbanti Katarko, Kognoli, Garga, | (1,066 - 6,528) | (162,000 - 257,000) | (65 – 200) | ||
Mayo Darle, Martap, Galdi | |||||
North-West | Misaje, Binshua, Binka, Dumbu, | ||||
Sabongari, Esu, Wum, Bafut | |||||
West | – | ||||
Local ( |
Adamawa | Mbe, Dang, Dangfili, Djalingo, | |||
Lougga, Belel, Beka Gotto, | |||||
Tourningal, Sambo Labo | 1,529 | 223,300 | 42 | ||
North-West | Kimbi, Subum, Ntumbaw, Mbiame, Weh, | (283–3,863) | (142,000–333,000) | (22–60) | |
Wainamah, Acha Tugi, Fundong, Lassin, | |||||
Saje-Babungo, Tingume-Babungo, Konene | |||||
West | Tayandi, Bafang, Bangambi, | ||||
Maloua, Ngon-Kham |
Examples and images of markets belonging to each of the identified classes are shown in
Examples of different livestock market classes across the study area.
Types of cattle traded across the four classes of livestock markets in the study area. On the x axis are the months of the year from the trading records (between September 2013 and August 2014), while the y axis reports the proportions over the total number of traded cattle per month. Blue refers to adult bulls, yellow to adult cows, red to steers, gray to young bulls and green to heifers.
The presence of other livestock species varied between market classes but showed overall consistent trends across “local,” “sub-regional,” and “regional” markets (
Livestock species, other than cattle, traded at the four classes of markets in the study area. The x axis reports the other livestock species traded at the different market classes (sheep, goats and poultry). On the y axis the green color refers to the percentages of markets where cattle and the other reported livestock are traded but do not mix in the sales pen. The orange color, by contrary, refers to the percentages of markets where the different species are sold in the same sales pen, therefore mixing with each other.
The interviewees indicated a wide range of infectious diseases and health conditions observed affecting animals traded through the marketing system. Dermatophilosis and foot and mouth disease (FMD) were consistently the most commonly reported infectious diseases across market classes (22–36% of interviewees) (
Major livestock diseases and health conditions reported at the different market classes. For each market class the reported diseases and health conditions affecting traded livestock are displayed on the x axis. The y axis indicates the percentage of markets where each specific conditions was reported as a problem affecting the animals (FMD, foot and mouth disease; CBPP, contagious bovine pleuro pneumonia; LSD, lumpy skin disease; bTB, bovine tuberculosis).
Overall, a number of other infectious diseases and health conditions were reported affecting traded animals, as shown in
Unsold animals at livestock markets were reported by a variable proportion of interviewees which were selling animals on the day of the interview. At “sub-regional” and “regional” markets the majority of the interviewees reported not having sold all of the cattle taken to the market (53 and 69%, respectively) (
Key livestock management practices across the market classes. On the x axis respondents are grouped by market class, while the y axis is reporting the proportion of respondents per answer (
When asked about the introduction in the herd of newly purchased animals, 27% of interviewees which were buying animals on the day of the interview reported introducing the acquired animal(s) on the same day as the purchase, and overall 87% introduced newly purchased animals into their herds within a week (
The livestock transhumance was reported as a seasonal management practice by about 30% of all interviewees, regardless if they were selling or buying animals on the day of the interview. This proportion was relatively consistent at “sub-regional,” “regional,” and “primary” markets (range: 27–31%;
At “local” markets, transhumance as a seasonal management practice was reported by a higher proportion of interviewees (45%) (
Livestock markets are central aggregation events along the livestock supply chain in diverse farming systems (
In SSA, particularly, there are still wide knowledge gaps, and very little published literature, on the characteristics of animal markets (
Cattle were by far the most common livestock traded at the live animal markets in the study area. Nevertheless, in about one third of the markets other livestock species were also sold (mainly small ruminants). Over the 12-month period of observation, the peak of cattle traded in the market system was recorded in December, however, the monthly trade volume was consistently larger during the rainy season (May-September). An increase in the live animals supply it is not uncommon concomitant with national and religious festivities (
Our study could only refer to a single year of observation and did not investigate drivers of livestock price. Nevertheless, we could observe that the period at which mean prices per head were higher, visually coincided with the period during which pasture productivity is lower (i.e., the dry season) and animal body conditions poorer. As age and gender of the traded animal are known determinants of live cattle price also in Cameroon (
Based on the cattle trade volumes, their mean commercial values and the intensity of stakeholder attendance at markets, four main classes of markets could be identified in the study area. “Local” and “sub-regional” markets are generally located in rural or semi-rural areas and considered as collection markets where about one out of two traded cattle tend to be a young animal (heifer or young bull) and where both cattle and small ruminants are often traded. “Regional” markets are generally located in, or close to, regional administrative or commercial hubs or in towns strategically located along key transport infrastructures (e.g., tar roads or railway). Higher numbers of animals are traded, compared to “local” and “sub-regional” markets, and only about 1/3 of the cattle supply over the year are young animals (heifer and young bull). These markets also represent terminal trading points where live animals are directly sold for human consumption or further traded toward “primary” markets in Cameroon, where traded cattle are almost exclusively adult males, or toward neighboring countries (
The variable proportions of cattle types traded across market classes might reflect different drivers for trading live cattle. More commercially valuable adult males at “regional” and “primary” markets are more suitable for human consumption (
Animal age, while being a key driver of livestock price formation as discussed above (
Unfortunately, the epidemiology of zoonotic diseases in Cameroon is still largely unknown and, despite evidence of the presence in the livestock populations of diseases such as brucellosis, leptospirosis, Q fever and Rift Valley Fever (RVF) (
The trade volumes, their seasonal variations, the diverse livestock species, as well as the variety of infectious diseases reported to affect traded animals are key features contributing to making livestock markets hotspots for the dispersal of infectious diseases (
Improving basic management practices at herd and market levels is, therefore, a priority. At market level, despite potential infrastructural constraints, correct separation between escorting and trading animals, and between different livestock species, is a relatively simply applicable measure. Effective segregation of new animals before herd introduction is also a measure which can be easily implemented for risk mitigation at herd level, and that could be effectively communicated to livestock stakeholders attending the markets.
Seasonal transhumance is another important management practice in SSA, in particular for coping with environmental constraints (
Although the list of reported diseases is likely not to be exhaustive of the health conditions affecting livestock in the country, to our knowledge, this is the first investigation listing and providing a quantitative assessment of predominant diseases affecting animals along the livestock supply chain in SSA. However, an obvious limitation of these specific findings is that disease reporting was only anecdotal and without any supporting diagnostic evidence. Additionally, this is not a complete representation of the livestock market system in Cameroon, particularly because we could not complete the study in the North and Extreme-North of the country. Another shortcoming of this survey was the convenient sampling, as a more robust sampling design could not be applied in this context where multiple stakeholders are hectically engaged in negotiations and transactions.
Animal markets have important socio-economic functions for livestock smallholders and producers, particularly in agricultural sectors with limited resources such as in SSA. Formal quantitative approaches are increasingly needed to understand the interactions between livestock production and trade systems, pathogen transmission and the wider environment. The design of cost-effective disease management strategies benefits of prior epidemiological knowledge, and this study aimed at providing the baseline for more evidence-based interventions where live animal trading constitutes a major risk for disease introduction and dissemination. Despite the strategic position of markets within the livestock supply chain, epidemiologists and risk managers face major constraints in accessing information on livestock markets characteristics, transactions, and management practices. Nevertheless, markets provide the opportunity for targeted mechanisms to manage risks associated with livestock production (e.g., demand and supply fluctuations) and animal health (e.g., spread of animals and zoonotic diseases). Based on information readily available at livestock markets in Cameroon, we proposed a rapid approach (1) to characterize major markets classes along the livestock supply chain, and we have (2) defined a relatively limited pool of infectious diseases predominantly affecting traded animals, as reported by livestock stakeholders. Furthermore, the identified (3) management practices at high risk for disease transmission, combined with the seasonal variations in trade volumes, offer the opportunity to inform evidence-based and strategic communication, surveillance and control approaches targeting the diverse market classes. These may include the establishment of a targeted surveillance system in the areas surrounding key markets, improving disease reporting by raising awareness and strengthening the reporting mechanisms, as well as improving management and biosecurity measures at the market and herd levels. Altogether, these findings also offer information to provide initial guidance for more evidence-based strategies to reduce animal and public health risks along the livestock supply chain.
This research was authorized by the Ministry of Scientific Research and Innovation (Research permit number: 0119/MINRESI/B00/C00/C010/nye), and approved by the Cameroon Academy of Sciences (approval number 0371/CAS/PR/ES/PO). In the United Kingdom approval was given by the Veterinary Ethical Review Committee of the Royal (Dick) Veterinary School of the University of Edinburgh (approval number 28/14). All methods for data collection were performed in accordance with the relevant regulations, and in compliance with the received guidelines. Interviewers were trained to provide the information regarding the consent process to be communicated to the participants and the informed consent was obtained from all subjects. Oral consent was obtained due to the variable level of literacy of the respondents. Prior to interviewing, the study objectives, procedures and the content of the questionnaires were also explained to the participants who were made aware that they were under no obligation to participate if they did not want to. Questionnaires were treated anonymously, therefore, they were assigned an identification number relative to the market and the date of collection.
PM, TP, VT, and BB: designed the study. PM, VN, and SH: performed the field work. PM: conducted the analyses, interpreted the results and drafted the manuscript. PM, TP, IH, KM, VT, and BB: revised and reviewed the manuscript.
The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.
Importantly the authors would like to thank all the herds owners, traders and other livestock stakeholders for their participation in the realization of this study. In addition, the authors gratefully acknowledge all the Delegates, veterinarians and personnel of the MINEPIA for their participation and collaboration in this study.
The Supplementary Material for this article can be found online at: