Topic:Anthelmintic Treatment
Anthelmintic treatment involves the use of drugs to control parasitic worm infections in horses. These treatments target various types of internal parasites, such as strongyles, ascarids, and tapeworms, which can affect equine health and performance. The administration of anthelmintics is a common practice in equine management to reduce parasite burdens and minimize the risk of disease transmission. Different classes of anthelmintics, including benzimidazoles, macrocyclic lactones, and pyrantel, are used based on the specific parasitic threats and resistance patterns. This page compiles peer-reviewed research studies and scholarly articles that explore the efficacy, resistance development, and management strategies associated with anthelmintic treatment in horses.
Evaluation of cambendazole paste against nematodes in horses in a field trial. The anthelmintic canbendazole (CBZ), adminis-
tered in several formulations to horses in critical
trials, has been shown to have high effcacy
against intestinal nematodes (3, 4, 6). There are
two reports of field trials with CBZ (2, 5), and
although a large number of horses were involved,
the efficacies reported were for a restricted
number of nematodes. Recently, CBZ paste was
administered to horses in another field trial and
the findings on rxdatability, safety and efficacy
against a wide range of nematodes are presented.
Studies on the faecal egg output of horses after treatment with fenbendazole. Examination of faecal egg counts in horses and ponies has shown that after treatment with fenbendazole at dose levels of 7.5, 45 and 60 mg/kg, faeces remained free from strongyle eggs for periods of 6 to 18 weeks. The significance of these results is discussed in relation to routine anthelmintic treatment of horses. In particular, the activity of fenbendazole against mucosal stages of strongyle parasites allows for treatment to be recommended at less frequent intervals than when using other anthelmintics.
Methods in the evaluation of antiparasitic drugs in the horse. The critical test is the primary method used for the efficacy evaluation of drugs against the major internal parasites (bots, ascarids, large strongyles, small strongyles, and pinworms) of the horse. The critical test determines: (1) spectrum of activity, (2) effectiveness of removal, (3) pattern of discharge, and (4) physical condition of each species of these parasites. General characteristics of the major parasitisms of the horse are discussed briefly. Criteria of the critical test also are considered including: (1) number of tests, (2) strain variation and drug resistance, (3) selection of...
[Cyathostominosis: a form of severe strongylidosis (author’s transl)]. A form of strongyle infection in young horses and ponies, observed during the period from November to May, is described. Large numbers of larvae of Cyathostominae in the fourth or early fifth stage of development are found to be present in the (often watery) faeces. This excretion of larvae is not affected by treatment with anthelmintics. A large number of these patients die from the sequelae of verminous enteritis.
Critical anthelmintic trials in ponies with four benzimidazoles: mebendazole, cambendazole, fenbendazole, and albendazole. The comparative efficacy of four benzimidazoles against gastrointestinal parasites of ponies was evaluated by the critical test method. Mebendazole (8.8 mg/kg), cambendazole (20 mg/kg), fenbendazole (5 mg/kg), and albendazole (2.5 and 5 mg/kg) given in single oral doses were highly effective against adult large strongylids (Strongylus vulgaris, S. endentatus, S. equinus) and adult small strongylids (genera identified in order of frequency: Cylicostephanus, Cylicocyclus, Cyathostomum, Triodontophorus, Poteriostomum, Oesophagodontus, Cylicodontophorus, Gyalocephalus, and Craterostomum). Limited ...
Critical tests of the antiparasitic activity of thiabendazole and trichlorfon sequentially administered to horses via stomach tube. Thirteen critical tests were conducted in horses naturally infected with helminths and bots. Single doses of thiabendazole (44 mg/kg of body weight) and trichlorfon (40 mg/kg of body weight) powder formulations were administered as suspensions sequentially given via stomach tube to evaluate the efficacy of the combination against the large parasites of horses. Parasite removal efficacies were 100% against 2nd instar Gasterophilus intestinalis and 2nd and 3rd instar Gasterophilus nasalis and 82 to 100% against 3rd instar G intestinals. There were complete removals of mature and immature Parasca...
Reproductive function in stallions treated with cambendazole. Twenty stallions were used to determine if the anthelmintic cambendazole affected seminal characteristics, spermatogenesis, concentration of testosterone in blood serum, or weights of the reproductive orgrans. With minor exceptions, significant differences were not found between values for 10 control and 10 stallions treated with a single oral dose (40 mg/kg body weight) of cambendazole. The treatment did not affect reproductive function and it was concluded that the drug should have no effect on the fertility of stallions.
An evaluation of ethyl-6-ethoxybenzothiazole-2-carbamate (Sch 18099) for anthelmintic activity in domestic animals. Ethyl-6-ethoxybenzothiazole-2-carbamate (Sch 18099) was evaluated for efficacy against natural helminth infections in ponies, pigs, lambs and chickens. Sixteen critical trials were conducted in ponies at dosages of 15 to 150 mg/kg. At 15 mg/kg, efficacy against adult and larval Oxyuris equi was 100% and 91% and against small strongyles it was 98%. Efficacy levels were 95% against Strongylus vulgaris and S. edentatus at the 20 mg/kg dosage. In two trials at 100 mg/kg efficacy against Parascaris equorum was 77%. No efficacy was observed against Gastrophilus spp. or Anoplocephala spp. In swine si...
Strongyle infections in ponies. I. Response to intermittent thiabendazole treatments. A group of seven ponies naturally infected with large numbers of small strongyles and raised under conditions to minimize reinfection were treated periodically over a three year span with thiabendazole at the rate of 44 mg/kg body weight. Based on the absence of worm eggs in the feces following each treatment, thiabendazole removed the adult strongyles present with a new population subsequently developing by maturation of inhibited larvae. It took as many as four or five treatments to eliminate or reduce significantly the worm burdens present in the ponies under the conditions of this study. S...
Strongyle infections in ponies. II. Reinfection of treated animals. Five of seven ponies whose strongyle worm burdens had previously been removed or markedly reduced by repeated thiabendazole treatments were reinfected with doses ranging from 100,000 to 500,000 small strongyle infective larvae. Reinfection of ponies resulted in the development of clinical signs characterized by abnormal feces, marked loss of weight and delayed shedding of winter hair coats. An abrupt increase in circulating eosinophils occurred during the first three weeks following reinfection. Patent infections developed in all ponies with worm eggs appearing in the feces from 12 to 15 weeks...
A practical health programme for prevention of parasitic and infectious diseases in horses and ponies. A scheme of combined anthelmintic treatment and vaccination is described. The seasonal veterinary activities are as follows: March (all horses); parasitological examination of faeces, anthelmintic treatment, immunization against influenza and tetanus (booster dose). June: parasitological faeces examination of foals, anthelmintic treatment of all horses, immunization of foals against tetanus (1st dose). August: anthelmintic treatment of all horses and immunization of foals against influenza (1st dose) and tetanus (2nd dose). October: parasitological faeces examination and anthelmintic treatment...
Critical tests of anthelmintic activity of a paste formulation of thiabendazole in horses. Critical tests of the activity on large strongyles, ascarids, mature pinworms, and bots were carried out in 11 horses intraorally treated with a paste formulation of thiabendazole. The dose level of 44 mg/kg was administered to 3 horses, and the dose level of 88 mg/kg to 8 horses. Removals of Strongylus vulgaris and mature Oxyuris equi were 100% at the 2 dose levels, and efficacy against Strongylus edentatus varied from 95 to 99% and 89 to 100% for the 44- and the 88-mg/kg dose levels, respectively. Strongylus equinus was completely removed from the 1 infected horse treated at the dose level o...
Critical tests with oxibendazole against gastrointestinal parasites of ponies. Twenty ponies were allotted to 4 groups of 5 ponies each, and oxibendazole was orally administered at dose levels of 5, 10, 15, and 20 mg/kg. In the 3 groups of ponies given the largest doses, efficacy against 3 species of Strongylus was between 92 and 100% and that against small strongylids of the genera Cyathostomum, Cylicocyclus, Cylicodontophorus, and Cylicostephanus was more than 99%. All adults and 95 to 100% of larvae of the pinworm Oxyuris equi were removed. In the group of ponies given 5 mg/kg, 86 to 100% of the large strongylids and 84 to 100% of the small strongylids were removed, a...
Effect of antiparasitic medication in ponies on pasture. Twenty Shetland ponies, 6 to 7 months old, were naturally infected with gastrointestinal nematodes and stomach bots. The ponies were allotted to 2 groups of 10 and were maintained on separate similar pastures that were free of infective larvae at the beginning of the study. The ponies in 1 group were treated monthly for 17 months with a therapeutic dose of a thiabendazole and piperazine mixture; those in the other group were not treated. During the 3rd and 5th months of the experiment, the ponies in the treated group were also given therapeutic doses of dichlorvos to remove bots. Various physi...
Oxibendazole: critical anthelmintic trials in equids. The efficacy of oxibendazole against gastrointestinal parasites of horses was evaluated by the critical test method. Naturally infected ponies of various ages were given single oral doses of 5, 10, or 15 mg-kg of bodyweight. The drug was highly effective against adult large strongylids (Strongylus vulgaris, S edentatus, S equins), adult small strongylids (especially species of the genera Cylicostephanus, Cylicocyclus, Cyaathostomum, and Triodontophorus), and adult and larval stages of the large pinworm, Oxyuris equi. There was no apparent dose-related differences in efficacy. Oxibendazole was ...
[Concerning the toxicity of parbendazole (Helmatac 30) to horses and ponies (author’s transl)]. The toxicity of parbendazole in different doses was investigated with 52 horses and 16 ponies, in twelve groups. Side effects observed with the anthelmintic were laxation (soft dung, diarrhoea), anorexia, and listlessness. The seriousness of these symptoms depended greatly on the dose used. Half the therapeutic dose of parbendazole (2.5 to 3.75 mg/kg) administered on two consecutive days led, as a rule, to only slight toxic symptoms and proved highly effective with regard to gastro-intestinal nematodes occurring in horses and ponies. The utilisation of "standard powders" (not commercially avai...