nitrophenols and disophenol

This paper describes an exceptional spectrum of multiple anthelmintic resistance in two strains of Haemonchus contortus in South Africa, one from Howick in KwaZulu-Natal, and the other from Badplaas, in Mpumalanga. Apparently for the first time, a helminth strain is described with resistance to compounds from all five of the modern anthelmintic groups used for nematode control in sheep; also, two strains of H. contortus show resistance to the two substituted phenols, dinitrophenol and nitroxynil. Only closantel at 5 mg kg-1 of nine compounds tested appears to have undiminished efficacy against the Howick strain, but even in the case of closantel, the residual activity and minimal effective level need to be tested before it can be concluded that its efficiency is unaffected. The exceptional resistance of the Howick strain is demonstrated by the fact that sequential daily drenching of sheep infected with the strain, with levamisole at 18 mg kg-1, oxfendazole at 20 mg kg-1, levamisole at 20 mg kg-1 and a mixture of fenbendazole at 10 mg kg-1 plus trichlorfon at 132 mg kg-1 on the fourth day, failed to clear sheep of the infection. There are strong indications that side-resistance occurs between dinitrophenol and nitroxynil, on the one hand, and the salicylanilides, on the other, and it is suggested that, before long, strains of H. contortus will be found with high levels of resistance to all the currently available anthelmintics.

Topics: Animals; Antinematodal Agents; Drug Resistance, Multiple; Female; Haemonchiasis; Haemonchus; Male; Nitrophenols; Nitroxinil; Salicylanilides; Sheep; Sheep Diseases; South Africa

Topics: Albendazole; Animals; Anthelmintics; Brazil; Drug Resistance, Multiple; Feces; Fenbendazole; Haemonchiasis; Haemonchus; Ivermectin; Levamisole; Nematoda; Nematode Infections; Nitrophenols; Parasite Egg Count; Salicylanilides; Sheep; Sheep Diseases; Trichostrongylosis; Trichostrongylus

Outbreaks of tetanus, in which 297 beef cattle and 50 sheep were affected and died, were associated with the injection of a Clostridium tetani-contaminated anthelmintic (disophenol). The disease was observed on five farms in Rio Grande Sul, Brazil.

Topics: Animals; Brazil; Cattle; Cattle Diseases; Disease Outbreaks; Equipment Contamination; Female; Male; Nitrophenols; Sheep; Sheep Diseases; Tetanus; Vaccines

Sheep grazed on natural pastures heavily infested with infective larvae of Haemonchus contortus. Sixty-eight weaned Merinos were divided into 6 groups on Day 0 (23 November 1977), and on Day +14 (7 December) 79 Merinos were divided into 7 groups. There were 2 groups of undosed controls and other groups were either dosed with infective larvae of Trichostrongylus axei (bovine strain) only on Days 0 and +14, or in combination with H. contortus, or with subsequent doses of H. contortus, 28 days later. One group (Group 12) was dosed with T. axei and treated with a subcutaneous injection of di-iodonitrophenol (DNP) on Day +14. With the exception of 2 sheep, the sheep of the first 6 groups survived until slaughter in March and April 1978, while many sheep (43) of the latter 7 groups died or were killed in extremis from March-May. T. axei dosed on 23 November (Day 0) protected Group 2 by greater than 50% in greater than 50% of sheep. In the latter 7 groups the best results were achieved when DNP was combined with predosing with T. axei. The poor results were probably due either to delayed predosing with T. axei or a massive challenge in the wettest summer on record.

Topics: Animals; Cattle; Feces; Haemonchiasis; Haemonchus; Host-Parasite Interactions; Nitrophenols; Parasite Egg Count; Sheep; Sheep Diseases; Trichostrongyloidea; Trichostrongyloidiasis; Trichostrongylosis

A man with massive Capillaria hepatica infection survived after treatment with prednisone, disophenol, and pyrantel tartrate. He remained well during an 8-year follow-up.

Topics: Adult; Antinematodal Agents; Capillaria; Drug Therapy, Combination; Humans; Male; Nematode Infections; Nitrophenols; Prednisone; Pyrantel; Pyrantel Tartrate

Topics: Ancylostoma; Ancylostomiasis; Animals; Anthelmintics; Dichlorvos; Dog Diseases; Dogs; Feces; Larva; Nitrophenols; Prednisolone

Haematological parameters and liver specific serum enzymes were examined in pigs during the first 12 weeks of liver migration of larvae following experimental infection with 1000 infective Stephanurus dentatus larvae. No significant changes in total red blood cell counts, packed cell volume, or haemoglobin content were observed. Total white blood cell counts and circulating eosinophils rose rapidly from days 5 and 19 after infection, respectively. Treatment with a mixture of levamisole (LEV) at 10 mg/kg and flubendazole (FLU) at 50 mg/kg in feed four weeks after infection halted the leucocyte response and returned values to normal in two weeks. Disophenol (DIP) at 15 mg/kg subcutaneously restricted the leucocyte response but it was only terminated following FLU treatment alone on day 61. No effects of S dentatus or either anthelmintic treatments on liver specific serum enzymes glutamate dehydrogenase, sorbitol dehydrogenase or gamma-glutamyl transpeptidase were found. Animals killed seven, 26 and 54 days after treatment showed significant resolution of fibrotic liver lesions after LEV + FLU but not after DIP. We conclude that LEV + FLU is an effective treatment for prepatent stephanuriasis but that liver damage is insufficiently traumatic to release sufficient enzymes into serum to be pathognomonic or to assess anthelmintic efficacy.

Topics: Animals; Anthelmintics; Benzimidazoles; Levamisole; Liver; Mebendazole; Nematode Infections; Nitrophenols; Strongylida Infections; Swine; Swine Diseases

Topics: Animals; Drug Interactions; Electrocardiography; Heart; In Vitro Techniques; Male; Mitochondria, Heart; Myocardial Contraction; Nitrophenols; Polymers; Prostaglandins; Prostaglandins B; Prostaglandins, Synthetic; Rats

Topics: Adult; Capillaria; Drug Therapy, Combination; Humans; Liver; Male; Nematode Infections; Nitrophenols; Prednisone; Pyrantel; Pyrantel Tartrate

A subcutaneous injection of 2,6-diiodo-4-nitrophenol (Disophenol) at 10 mg/kg sheep leaves a residue bound to serum albumin which is lethal to Haemonchus contortus for 3 months after treatment. In the larval anthelmintic test, susceptible worm free sheep are dosed so that either third stage larvae (L3), or fourth stage larvae (L4) or 5th and adult stages are present on the day of treatment but slaughter is delayed to allow these larval stages to develop to adults because the larger worms are more easily seen, identified and counted. The larval anthelmintic test in sheep had to be altered and sheep killed within a few days of treatment, because the residues may be more effective against subsequent stages of development. Disophenol was greater than 60% effective against L3 of Oesophagostomum columbianum and L4 of H. contortus in greater than 60% of sheep (Class B). It rose to greater than 80% effective against adult H. contortus in greater than 80% of sheep (Class A). Against H. contortus it maintained Class A for 32 days, fell to Class B from 45--76 days and Class C (greater than 50% effective in greater than 50% of sheep) at 91 days after treatment respectively. In the RSA a treatment in December followed by another in March would protect sheep adequately against H. contortus for the entire season.

Topics: Animals; Anthelmintics; Delayed-Action Preparations; Drug Evaluation; Feces; Haemonchiasis; Helminthiasis; Helminthiasis, Animal; Larva; Nitrophenols; Oesophagostomiasis; Parasite Egg Count; Sheep; Sheep Diseases

Two long-acting anthelmintics, closantel and disophenol, were tested by treatment 90, 60 and 30 days before challenge with a thiabendazole selected laboratory strain of Haemonchus contortus. The sheep were slaughtered 28 days after infection for total worm counts. A significant reduction in the number of adults remaining at autopsy was recorded after treatment with both anthelmintics 30 and 60 days before challenge but there was zero efficacy when the animals were treated 90 days before challenge. No significant difference was exhibited between the two compounds. Variability in response was recorded between animals on the 60 day period of treatment, which for disophenol may be dose related because animals receiving the lower volumes showed higher worm counts. For both anthelmintics a variability in the rate of metabolism may be responsible. The possibility offered by both anthelmintics for treating benzimidazole resistant strains of H contortus is discussed.

Topics: Animals; Anthelmintics; Drug Resistance; Haemonchiasis; Haemonchus; Nitrophenols; Salicylamides; Salicylanilides; Sheep; Sheep Diseases; Thiabendazole; Trichostrongyloidiasis

A group of 12 10-month-old, worm-free Merino lambs were given a single injection of disophenol at 10 mg/kg. This group and another group of 12 worm-free lambs were infested with infective larvae of Haemonchus contortus 1-3 times a week with a maximum dose of 4000/week from 0-91 days. From 95-168 days the dose was increased to a maximum of 6000/week. Every 7 days faeces were examined for worm eggs and blood samples for haematocrit (Ht). Worm egg counts in the controls rose from 21-56 days, fluctuated, and rose to another peak at 84 days, while the Ht fell from 28 days to rise again after 105 days. In the group treated with disophenol egg counts were negative until 161 days and Ht remained at normal values throughout.

Topics: Animals; Anthelmintics; Feces; Haemonchiasis; Hematocrit; Nitrophenols; Parasite Egg Count; Sheep; Sheep Diseases; Time Factors; Trichostrongyloidiasis

Topics: Acute Disease; Animals; Haemonchiasis; Nitrophenols; Parasite Egg Count; Rain; Seasons; Sheep; Sheep Diseases; Trichostrongyloidiasis

Six critical tests with disophenol were conducted in July, 1978, in fur seal pups (Callorhinus ursinus) naturally-infected with adult hookworms, Uncinaria lucasi, and infested with various stages of two species of sucking lice, Proechinopthirus fluctus (Ferris) and Antarctophthirus callorhini (Osborn). Disophenol at a dose rate of 12.5 mg/kg was administered subcutaneously to each of six pups. Each pup was contained in an individual cage for 60 h posttreatment at which time pups were exmained at necropsy. Efficacy against hookworms ranged from 2% to 88% and of both species of lice ranged from 26% to 90% for the six pups. Disophenol removed approximately 90% of all adult lice but only slightly more than 60% of all nymphs. The only sign of toxicosis was a probable drug related fluid-like feces for four pups from 12 to 60 h posttreatment.

Topics: Alaska; Animals; Caniformia; Fur Seals; Hookworm Infections; Lice Infestations; Nitrophenols

Twelve doses of Ancylol Disophenol at 0.05 ml per pound body weight administered subcutaneously was shown to be an effective chemotherapeutic agent against migrating stage of G. spinigerum in cats. A further investigation is required to determine whether this regimen is the minimum effective therapeutic dosage. None of eight cats treated with 12 doses of 0.02 to 0.05 ml per pound body weight showed signs or symptoms of toxicity due to the treatment and there were not gross pathological changes of the organs observed on necropsy of the animals.

Topics: Animals; Cat Diseases; Cats; Dose-Response Relationship, Drug; Gnathostoma; Injections, Subcutaneous; Nematode Infections; Nitrophenols

The result of a field trial investigating the anthelmintic effect of disophenol against H. contortus in sheep raised under Asian small farming practice is reported. it was clearly shown that a single injection of disophenol suppressed the numbers of H. contortus to very low levels for periods up to 3 months despite the presence of large populations of H. contortus infective larvae available on pasture and herbage grasses.

Topics: Animals; Anthelmintics; Feces; Female; Haemonchiasis; Haemonchus; Indonesia; Male; Nitrophenols; Parasite Egg Count; Sheep; Sheep Diseases; Trichostrongyloidiasis

Topics: Animals; Anthelmintics; Biotransformation; Chemical Phenomena; Chemistry; Dinitrophenols; Dogs; Necrosis; Nitrophenols; Rats

One controlled and six critical tests were conducted in July, 1977 with northern fur seal pups (Callorhinus ursinus) to determine the efficacies of a single dose of dichlorvos capsules at 29.3 to 32.8 mg/kg, tablets at 10.5 to 11.5 mg/kg, or disophenol at 9.9 mg/kg given subcutaneously against natural infections of adult Uncinaria lucasi. In the controlled test, 20 pups were treated and 10 pups were nontreated. Removal of hookworms in this test was 99% for five pups receiving dichlorvos capsules, 99% for five pups receiving dichlorvos tablets, and 77% for 10 pups receiving disophenol. Also, both formulations of dichlorvos and the formulation of disophenol were highly active against natural infestations of two species of sucking lice (Proechinophthirus fluctus and Antarctopthirus callorhini). In critical tests with four pups treated with dichlorvos capsules at 28.6 to 30.6 mg/kg, removal of hookworms was uniformly 100%. Disophenol at 9.9 mg/kg removed 100% and less than 1% of hookworms in two pups, respectively, in critical tests.

Topics: Alaska; Animals; Caniformia; Dichlorvos; Female; Fur Seals; Hookworm Infections; Lice Infestations; Male; Nitrophenols

Topics: Animals; Antinematodal Agents; Coronary Circulation; Electrocardiography; Freezing; Heart; Heart Rate; Histocytochemistry; In Vitro Techniques; Lactates; Male; Myocardial Contraction; Myocardium; Nitrophenols; Perfusion; Phosphorylases; Rats

Topics: Age Factors; Animals; Cataract; Dog Diseases; Dogs; Nitrophenols

Disphenol was administered to sheep infected with Haemonchus contortus in order to prevent the development of populations of adult worms, and studies were made of the pathogenicity of the arrested fourth-stage larvae which remained. The treated sheep showed elevated plasma pepsinogen and abomasal pH, predominantly negative dry-matter balance, and evidence of greater fluid loss, including plasma, into the gastro-intestinal tract. It was concluded that arrested larvae may cause damage to the abomasal mucosa.

Topics: Abomasum; Animals; Haemonchiasis; Haemonchus; Larva; Male; Nitrophenols; Pepsinogens; Sheep; Sheep Diseases; Trichostrongyloidea; Trichostrongyloidiasis

Topics: Animals; Anthelmintics; Dog Diseases; Dogs; Nematode Infections; Nitrophenols; Thelazioidea

Topics: 2,4-Dinitrophenol; Blood Cell Count; Blood Chemical Analysis; Dinitrophenols; Dogs; Injections; Injections, Intraperitoneal; Injections, Intravenous; Injections, Subcutaneous; Mice; Nitrophenols; Pharmacology; Rats; Research; Toxicology; Urine

Topics: Ancylostomatoidea; Animals; Anthelmintics; Dog Diseases; Dogs; Hookworm Infections; Nitrophenols