Reduction rate of nematode egg counts and third-stage larvae development from sheep and goat faeces preserved at 4οC

Abstract

ABSTRACT. Gastrointestinal nematode parasites cause major production losses to small ruminants. The most common way to diagnose or monitor the worm burdens in sheep and goats remains the quantitative parasitological examinations, i.e. the faecal egg counts. However, the reliability of the results of such methods depends greatly on the conditions and duration of the storage of the faecal samples prior to examination. The aim of this research was to evaluate the reduction rate and the maximum storage period, without significant losses, of nematode egg counts and third-stage larvae development from sheep and goat faeces preserved at 4οC. Towards this end, a pooled faecal sample was formed by collecting faeces from naturally infected sheep and goats (separately). Faecal egg counts and coprocultures were performed on fresh faeces and on preserved ones every week and up to 119 days post sampling. It was concluded that the preservation at 4 o C, i.e. into a refrigerator, of fresh faeces from sheep and goats for parasitological examinations poses danger of misdiagnosis, if not performed in a period not exceeding 3 weeks of time. The rate of reduction of the faecal nematode egg counts starts to be significant lower than the ones performed with fresh samples, for both sheep and goats, after the third week of storage. The percentage of the gastrointestinal nematode larvae developing to the infective third-stage alters significantly for the Haemonchus genus, soon after the first week of storage (p<0.05). Keywords

Both candidate gene and neutral genetic diversity correlate with parasite resistance in female Mediterranean mouflon

“…Variables considered included the year and the Julian date of sampling to account for intra and inter-annual variations in environmental conditions and population densities. We corrected for part of the sampling variance by adding the number of days between sampling and coproscopic analyses in the models since it can impact the number of fecal egg and oocyst counted [159, 160]. We only considered individuals for which less than 30 days elapsed between the sampling and laboratory analyses.…”

Reproductive females and young mouflon (Ovis gmelini musimon×Ovissp.) in poor body condition are the main spreaders of gastrointestinal parasites

“…Faecal eggs counts (FEC) and faecal oocysts counts (FOC) tend to decrease as the time elapsed between faeces collection (i.e. sampling date) and coproscopic analyses increases (Drimtzia and Papadopoulos, 2016;Portanier et al, 2019), but the date in which coproscopic analyses were performed was nevertheless not available for all the samples. During the study period, the number of persons available to analyse the faecal samples varied.…”

“…According to the seasonality of parasitism (Wilson et al, 2004;Magi et al, 2005;Balicka-Ramisz et al, 2017), we expected to observe an influence of the sampling date on FEC and FOC and thus included the day of year of sampling in models (sampling date). We also tested for an influence of the time elapsed between faeces collection and coproscopic analyses (delay) (Drimtzia and Papadopoulos, 2016;Portanier et al, 2019). Only samples with a delay ⩽30 days were considered in the analyses.…”