Prevalence and diversity of ecto- and endoparasites in backyard chickens (Gallus gallus domesticus) in households in Brazzaville (Republic of Congo)

Technical Summary: Prevalence and Diversity of Ecto- and Endoparasites in Backyard Chickens in Brazzaville

Problem Statement
Backyard poultry production serves as a critical source of animal protein and household income across sub-Saharan Africa. However, the productivity of these flocks is frequently constrained by parasitic infections. Despite the economic and nutritional importance of these birds, there is a need to characterize the specific parasitic burdens affecting backyard chickens in the Republic of the Congo to inform management strategies.

Methodology
This study was conducted in households in Brazzaville, Republic of the Congo, between September 2023 and March 2024. The research focused on a sample size of 37 backyard chickens (Gallus gallus domesticus). The investigation employed a dual approach to parasitological assessment:

• Ectoparasites: Collected via direct physical examination of the birds.
• Endoparasites: Identified through coprological (fecal) analyses.
  The study quantified prevalence, diversity, and relative abundance, while also analyzing infection patterns based on host age (young vs. adults) and sex (female vs. male). Ecological indices were calculated to assess parasite diversity.

Key Results
The study revealed a high overall parasite prevalence of 86.5% among the examined flock.

• Ectoparasite Profile:

  • A total of 3,594 ectoparasite specimens were collected.
  • Lice were the overwhelmingly dominant group, constituting 98.64% of all ectoparasites.
  • Fleas and mites represented minor proportions at 1.22% and 0.14%, respectively.
  • Menopon gallinae was identified as the most abundant ectoparasite species.
  • Ecological indices indicated moderate diversity within the ectoparasite community.

• Endoparasite Profile:

  • A total of 124 endoparasites were identified.
  • The community was dominated by protozoa (70.16%), followed by nematodes (27.42%) and mites (2.42%).
  • Eimeria spp. was the predominant taxon among endoparasites.
  • Endoparasite diversity was noted to be lower than that of ectoparasites, reflecting the dominance of specific taxa.

• Infection Patterns:

  • Multiple infections were highly frequent, accounting for 85.47% of all mixed infections observed.
  • Demographic Susceptibility: Young chickens exhibited higher infestation rates compared to adults. Additionally, female chickens were more affected than males.

Key Contributions
This work provides the first detailed assessment of the prevalence, diversity, and relative abundance of both ecto- and endoparasites in backyard chickens specifically within Brazzaville. It establishes a baseline data set characterizing the specific parasite taxa (notably Menopon gallinae and Eimeria spp.) and quantifies the high rate of co-infections in this specific urban/sub-urban context.

Significance and Claims
The paper asserts that parasitic infections are widespread in backyard chickens in Brazzaville. The findings underscore the necessity for improved parasite control measures and enhanced sanitary management practices. The authors conclude that addressing these parasitic burdens is essential to improving poultry health and, consequently, the productivity of backyard flocks in the region. The study does not propose specific new treatments or future experimental protocols but rather emphasizes the immediate need for better management based on the documented prevalence.