Diversity of Eimeria (Apicomplexa: Eimeriidae) species and risk factors associated in natural infecting calves at the Southern Agreste Microregion in the State of Pernambuco, Brazil

Abstract

Eimeria species have importance to calves because of the economic losses. The aim of this study was to identify the species of Eimeria that affect calves and the risk factors associated with its natural infection. Fecal samples (387) were collected from dairy farms in the southern Agreste of Pernambuco. The feces were evaluated using the Gordon & Whitlock technique and were cultured in 2.5% potassium dichromate for sporulation of oocysts. Odds ratio (OR) were calculated to assess risk factors. Eimeria spp. were detected in 50.65% (196/387) of the samples. Eleven species were identified, being Eimeria bovis (26.64%; 548/2057), Eimeria zuernii (19.69%; 405/2057) and Eimeria ellipsoidalis (14.49%; 298/2057) those more frequent. Small herds (OR = 1.93), calves aged up to six months (OR = 2.12), absence of manure pit (OR = 7.52), fortnightly cleaning (OR = 4.71), collective calf pens (OR = 3.26), manual milking (OR = 2.16) and absence of veterinary care (OR = 2.28) were considered to be risk factors. The data revealed pathogenic species in more than 50% of the farms. Thus, the importance of adopting sanitary measures to reduce the spread of these protozoa in herds should be done, because of economic losses associated with its infection.

Molecular identification of Eimeria species in cattle from Veracruz, Mexico

“…Veracruz is the state with the highest number of registered heads of cattle, approximately 4.5 million (SIAP, 2020). Livestock farms are under extensive grazing conditions, so one of the limiting factors is the presence of parasites (Zhao et al, 2005 The diagnosis of Eimeria species has been carried out mainly through morphological identi cation using taxonomic keys (Floriáo et al, 2016;Ekawasti et al, 2021;Santos et al, 2022); but the authors agree that it can be subjective and ambiguous if trained personnel are not available to perform the identi cation (Floriáo et al, 2016) or because some species are di cult to differentiate between them. Also, there is the possibility of morphological changes due to the application of some antiparasitic treatment before sampling or due to the manipulation of the samples in the sporulation process (Li et al, 2010).…”