Prevalence and seasonal variation of Fasciola hepatica in slaughtered cattle: the role of climate and environmental factors in Mexico

Abstract

The objective of this study is to determine the prevalence of Fasciola hepatica infection in cattle slaughterhouses, as well as its association with climatic/environmental factors (derived from satellite data), seasonality and climate regions in two states in Mexico. Condemned livers from slaughtered animals were obtained from three abattoirs in the states of Puebla and Veracruz. The overall prevalence of the parasite in cattle between January and December of 2017 was 20.6% (1407 out of 6834); the highest rate of condemnation was observed in Veracruz (26.3%; tropical climate), and the lowest rate was found in Puebla (15.5%; temperate climate). The seasonal prevalence of fluke infection was 18.6%, 14.8% and 28.4% during the wet season, and 17.1%, 12.4% and 22.8% during the dry season in the three abattoir sites, located in the districts of Zacatlán, Teziutlán and Ciudad Alemán, respectively. Liver condemnations due to bovine fasciolosis were prevalent in the Zacatlán, Teziutlán and Ciudad Alemán districts during summer, autumn and summer, respectively. Using generalized estimating equations analysis, we determined six variables – rainfall (wet/dry), land surface temperature day, land surface temperature night, normalized difference vegetation index, seasonality and climate regions (temperate/tropical) – to be significantly associated with the prevalence of condemned livers. Climate region was the variable most strongly associated with F. hepatica infection (odds ratio (OR) 266.59; 95% confidence interval (CI): 241.90–353.34), followed by wet and dry seasons (OR 25.56; 95% CI: 20.56–55.67).

High Prevalence of Bovine Cardiac Cysticercosis in Upper Egypt: An Epidemiological and Histopathological Study

“…Before entering the slaughterhouses, most animals have been grazing in surrounding pastures, while imported breeds are reared through intensive farming breeding systems. It is important to note that the prevalence of cysticercosis may be influenced by various factors, including climate and animal husbandry practices [ 28 ]. Regarding seasonal variation, there is limited information available on the seasonal prevalence of C. bovis in Egypt.…”

Prevalence, coinfection, and risk factors associated with Fasciola hepatica and other gastrointestinal parasites in cattle from the Peruvian Amazon

“…The presence of more than ten worms in the liver has a sensitivity and specificity of 80%-90% [39][40][41], respectively. As mentioned in the materials and methods section, the feces were collected between November and January (the beginning of winter), when the release of F. hepatica eggs rises [42]. Thus, it is highly probable that more animals tested positive for this parasite.…”

Prevalence of flukes (Fasciola hepatica and paramphistomids) in cattle in south-eastern Mexico

“…In slaughterhouse studies show a higher prevalence for F. hepatica due to the presen ce of eggs in the bile content (39.4 %) and lower prevalence due to the presence of adult parasites in the bile ducts (32.4 %) and the egg count (15.5 %) in faeces (Giraldo Forero et al, 2016). However, studies in slaughterhouses show a great variability in results with values as low as 12 % and up to 30 % with the condemnation of livers due to the presence of F. hepat ica (Hernández-Guzmán et al, 2021). The low prevalence of F. hepatica (1 %) in the slaughterhouses of the present study can be associated with the fact that they were the result of samplings carried out at fixed times and not of the systematic registration of all animals that entered the slaughterhouses.…”

“…In the case of rumen flukes, there was a five times greater probability of infection in flood-prone areas than in the hills. Environmental conditions have been considered as one of the main factors affecting the distribution of F. hepatica (Hernández-Guzmán et al, 2021), among which the type of soil, precipitation and altitude stand out (Jiménez-Rocha et al, 2017), as confirmed by a study in Bangladesh (Khan et al, 2017). These factors affect the distribution of both liver and rumen flukes and their intermediate host, snails of species as Gal ba truncatula (Jones et al, 2022) Lymnaea glabra (Dreyfuss et al, 2014;Naranjo-Lucena et al, 2018) and in Mexico the presence of Fossaria humilis and F. bulimoides (Cruz-Mendoza et al, 2004) is related with the presence of F. hepatica.…”

“…In the place of origin, differences were observed in the prevalence of both trematodes, which is the result of multiple factors that affect the presence of the parasite, as suggested by studies that address the diagnosis of these trematodes (Hernández-Guzmán et al, 2021;Jiménez-Rocha et al, 2017;Jones et al, 2022;Naranjo-Lucena et al, 2018). Females presented higher prevalence than males because this last receive different health and nutritional management that females, especially when they are destined for slaughter.…”