Prevalence of Select Intestinal Parasites in Alabama Backyard Poultry Flocks

Abstract

Keeping chickens as backyard pets has become increasingly popular in the United States in recent years. However, biosecurity is generally low in backyard flocks. As a consequence, they can serve as reservoirs for various pathogens that pose a risk for commercial poultry or human health. Eighty-four fecal samples, 82 from chickens and two from turkeys, from 64 backyard flocks throughout the state of Alabama were collected in the summers of 2017 and 2018. Coccidia oocysts were seen in 64.1% of flocks with oocyst counts in most samples below 10,000 oocysts per gram. Eggs of Ascaridia spp. or Heterakis gallinarum were observed in 20.3% of the flocks, and eggs of Capillaria spp. in 26.6% of the flocks. Egg counts were low, rarely exceeding 1000 eggs per gram. DNA extracted directly from fecal samples was investigated by PCR for other relevant parasites. The results showed that 4.7% of flocks were positive for Histomonas meleagridis, 18.8% of flocks for Tetratrichomonas gallinarum, 18.8% of flocks for Cryptosporidium spp. and 87.5% of flocks for Blastocystis spp. The results will help to provide information that can be used to design outreach programs to improve health and wellbeing of birds in backyard flocks.

Implementation of Mini-FLOTAC in Routine Diagnosis of Coccidia and Helminth Infections in Domestic and Exotic Birds

“…Organic layers from the poultry farm had a moderate Eimeria spp. prevalence (41%), similar to previous research in free-range/organic broiler and layer flocks, which highlights the importance of regular monitoring of birds’ health status, namely through periodic blood and fecal samplings for parasitological analysis [ 6 , 9 , 10 ]. These birds were not subjected to any antiparasitic drug program since organic animal production is extremely regulated in the European Union, and it is forbidden to use antiparasitic drugs for prophylactic purposes, which therefore poses a higher risk of developing parasitic diseases in organic flocks.…”

“…Coccidia belonging to the genus Eimeria were the most prevalent intestinal parasites in organic layers and peacocks from all locations, which confirms this group of parasites as ubiquitous in several species of domestic and exotic Galliformes [ 6 , 8 , 23 , 28 ].…”

“…However, the overall Eimeria spp. shedding in these birds was considerably low (24 OPG), which can be explained by the advanced age of the flock (16 months) and the low stocking density, reflecting a potential equilibrium between the parasite and the host immune system, which is common in older domestic birds [ 6 , 9 , 29 , 30 ].…”

“…Free-range poultry and captive wild birds are commonly housed in limited areas with high animal stocking and access to the environment and co-habit with other bird species and wild avifauna, consequently being exposed to a wide variety of generalist or host-specific gastrointestinal (GI) parasites, namely coccidia and helminths, which are still responsible for severe health and economic concerns in poultry farms and zoological collections worldwide [ 1 , 2 , 3 , 4 , 5 , 6 ].…”

“…Coccidia infections in Galliformes from free-range farms, zoos and public gardens can reach prevalence and shedding values of up to 80% and 15,000 oocysts per gram of feces (OPG), respectively [ 1 , 6 , 7 , 8 , 9 , 10 ]. Avian helminth infections are also a reality in traditional free-range farms, private exotic collections and public gardens, with ascarids (e.g., Ascaridia galli ), heterakids (e.g., Heterakis gallinarum and H. isolonche ), Trichostrongylus tenuis , Strongyloides spp.…”