Haemonchosis: A Challenging Parasitic Infection of Sheep and Goats

Abstract

The paper reviews the challenges about haemonchosis—a significant and common parasitic infection of small ruminants. Haemonchus contortus is a highly pathogenic parasite that localises in the abomasum of affected animals and exerts its pathogenicity by blood-sucking activity, adversely affecting the health and productivity of animals. The first challenge is the uneven distribution of the infection globally, this being more prevalent in tropical and subtropical and warm temperate and summer rainfall regions than in cool and cold temperate and arid regions; hence, this leads in differences in the approaches required for its control. Another challenge is the widespread presence of Haemonchus strains resistant to the various anthelmintics available: Benzimidazoles, imidazothiazoles, macrocyclic lactones, closantel and monepantel, which makes the control of the infection difficult. The third challenge refers to the difficulty of diagnosing the disease, given that field evidence can provide suspicion about the infection, which needs to be subsequently confirmed by laboratory tests through parasitological or molecular techniques. The final challenge relates to the difficulties in the control of the infection and the necessity to use pharmaceutical products cautiously and with a planned approach, to avoid further development of anthelmintic resistance, also given that use of a recently licenced vaccine is not widespread. In conclusion, at the moment, we should be concerned, but not worried, about this infection, and apply correctly the appropriate health management plans.

Antinematode Activity of Abomasum Bacterial Culture Filtrates against Haemonchus contortus in Small Ruminants

“…Haemonchus contortus has a great financial significance causing serious disease and death of cattle and ruminants [ 2 ]. Resistance to the available antihelmintic drugs has become a severe threat to livestock production [ 7 ].…”

“…This disease is caused by three species of the genus Haemonchus, namely, H. similis , H. placei , and H. contortus . Among these, H. contortus is one of the most prevalent nematode parasites that infect the abomasum of small ruminants worldwide [ 2 ]. It is commonly known as a red stomach worm, the wire worm, or the barber’s pole worm.…”

Recent Advances in the Control of Helminths of Domestic Animals by Helminthophagous Fungi

“…The internal parasites of ruminants is considered one of the main causes of important economic losses in cattle kept under pasture conditions, mainly in tropical and subtropical regions, due to the conditions of high temperature and humidity [41,42]. The absence of adequate anthelmintic control can lead to significant losses responsible for the decrease in food consumption, gastrointestinal disturbances, and compromised animal development, which can result in death in extreme cases [43,44].…”

Effect of Intensification Practices, Lambing Period and Environmental Parameters on Animal Health, and Milk Yield and Quality in Dairy Sheep Production Systems on Crete

“…Overall, results suggest that the relatively low levels of GIN disease pressure should allow further reductions in anthelmintic use in Crete by adopting FEC monitoring-based health management regimes [47]. H. contortus, which is a significant problem for the flocks in arid regions and was described as an "arising crisis" in Europe [48,49], was only identified in a small proportion (~12%) of faecal samples.…”