# Systematic review of the prevalence of Gastrointestinal helminths in ruminants in Mexico

## TL;DR

This paper reviews the prevalence of gastrointestinal helminths in ruminants in Mexico over 37 years to inform control measures.

## Contribution

A systematic review of helminth prevalence in Mexican ruminants using PRISMA guidelines and multiple databases.

## Key findings

- Haemonchus contortus had a prevalence of 38.8% in ruminants.
- Mecistocirrus prevalence in cattle was estimated at 40.5%.
- Cooperia and Strongyloides were the most prevalent nematodes in cattle's small intestine.

## Abstract

In Mexico, the abundance of endoparasites that affect the health of ruminants and the economy of the farmer, so the objective of this review was to determine the prevalence of the main genera and species of ruminant helminths that have been identified in Mexico in the last 37 years. A systematic search was carried out following the PRISMA 2020 guidelines and supported by the Elsevier platform (Scopus and ScienceDirect), Google Scholar, Redalyc and Scielo tools. In addition, information was sought in the proceedings Congress of the Buiatrics and Veterinary Parasitologists. A database was created with 36 documents containing information on the prevalence of gastrointestinal parasites in Mexico. Research studies that included treatments that affected prevalence were not included, nor were those of an experimental nature that did not aim to study prevalence. The prevalence for Haemonchus contortus, the main abomasal nematode in ruminants, was 38.8%. In the case of Mecistocirrus, only four studies indicated the prevalence in cattle, which was estimated at 40.5%. In the small intestine, the most prevalent nematode in cattle were Cooperia and Strongyloides. In goats and sheep, the presence of Trichostrongylus, and Toxocara were indicated. The main cecal nematodes include Trichuris and in the colon Oesophagostomum and Chabertia. The high prevalence of gastrointestinal nematodes in ruminants makes it essential to consider control measures to reduce their prevalence.