Occurrence of Eimeria Species Parasites on Small-Scale Commercial Chicken Farms in Africa and Indication of Economic Profitability

Abstract

Small-scale commercial poultry production is emerging as an important form of livestock production in Africa, providing sources of income and animal protein to many poor households, yet the occurrence and impact of coccidiosis on this relatively new production system remains unknown. The primary objective of this study was to examine Eimeria parasite occurrence on small-scale commercial poultry farms in Ghana, Tanzania and Zambia. Additionally, farm economic viability was measured by calculating the farm gross margin and enterprise budget. Using these economic measures as global assessments of farm productivity, encompassing the diversity present in regional husbandry systems with a measure of fundamental local relevance, we investigated the detection of specific Eimeria species as indicators of farm profitability. Faecal samples and data on production parameters were collected from small-scale (less than 2,000 birds per batch) intensive broiler and layer farms in peri-urban Ghana, Tanzania and Zambia. All seven Eimeria species recognised to infect the chicken were detected in each country. Furthermore, two of the three genetic variants (operational taxonomic units) identified previously in Australia have been described outside of Australia for the first time. Detection of the most pathogenic Eimeria species associated with decreased farm profitability and may be considered as an indicator of likely farm performance. While a causal link remains to be demonstrated, the presence of highly pathogenic enteric parasites may pose a threat to profitable, sustainable small-scale poultry enterprises in Africa.

Eimeria species occurrence varies between geographic regions and poultry production systems and may influence parasite genetic diversity

“…In northern India 43% of samples were positive for E necatrix , in contrast with just 15% in southern India. The high pathogenicity and economic cost associated with this parasite indicates greater risk of losses to north Indian poultry farmers (Fornace et al, 2013). More surprisingly, farms in the north Indian layer cluster were at a higher risk for many pathogenicity groups than those in the northern indigenous cluster.…”

“…Eimeria species were categorised into different pathogenic levels as described previously (Fornace et al, 2013). Specifically, E. necatrix was considered to be very highly pathogenic, E. brunetti and E. tenella were highly pathogenic, E. acervulina and E. maxima medium, with E. mitis and E. praecox primarily presenting a low pathogenicity risk.…”

Loop-mediated Isothermal Amplification (LAMP) Assays for the Species-specific Detection of <em>Eimeria</em> that Infect Chickens

“…One prime example are the Eimeria species, ubiquitous protozoan parasites which can cause the enteric disease coccidiosis 1 . Wherever chickens are reared one or more Eimeria species are likely to be common [2][3][4] . In the developed world Eimeria are primarily controlled by chemoprophylaxis, employing shuttle or rotation programmes to minimise the impact of resistance 5 .…”

“…In the developing world vaccination is rare and drug application frequently less well informed. As a consequence sub-clinical and clinical coccidiosis is more common and exerts a significant economic impact 3 .…”

“…Characterised by relative resistance to many PCR inhibitors, high sensitivity and specificity, LAMP assays have been developed for a wide range of pathogens including infectious bursal disease virus, Clostridium perfringens and Cryptosporidium . Applications for the new assays include monitoring parasite occurrence, of particular value given the association of species such as Eimeria maxima or Eimeria necatrix with poor economic performance 3,4 . Other applications include assessing the efficacy of a farm's anticoccidial strategy, diagnosis of sub-clinical infection or clinical disease and evaluation of risk posed by Eimeria to a farm.…”