Efficacy Of Diclazuril Research Articles

Assessment of the feed additive consisting of diclazuril (Clinacox® 0.5%) for chickens for fattening and chickens reared for laying for the renewal of its authorisation (Elanco GmbH).

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety and efficacy of diclazuril (Clinacox® 0.5%) as a coccidiostat for chickens for fattening and chickens reared for laying. The additive currently on the market complies with the existing conditions of authorisation. The additive remains safe for the target species and the consumer under the authorised conditions of use. The additive is irritant to skin, eyes and respiratory tract but is not a skin sensitiser. Exposure by inhalation cannot be excluded. The FEEDAP Panel cannot conclude on the safety for the environment of diclazuril from Clinacox® 0.5% due to lack of data. Diclazuril from Clinacox® 0.5% at a concentration of 1 mg diclazuril/kg complete feed has the potential to control coccidiosis in chickens for fattening. This conclusion is extended to chickens reared for laying. Development of resistance to diclazuril of field Eimeria spp. strains isolated from chickens should be monitored.

Experimental infection with Toxoplasma gondii in broiler chickens (Gallus domesticus): seroconversion, tissue cyst distribution, and prophylaxis.

Toxoplasma gondii is a widespread zoonotic protozoan that infects most species of mammals and birds, including poultry. This study aimed to investigate the course of T. gondii infection and the efficacy of diclazuril and Artemisia annua in preventing infection in experimentally infected chickens. Seventy-five 1-month-old chickens, female and male, were randomly divided into five groups (n = 15 each) as follows: (1) uninfected untreated (negative control, NC); (2) infected with T. gondii genotype II/III isolated from a wild cat (group WC); (3) infected with T. gondii genotype II isolated from a domestic cat (group DC); (4) infected with T. gondii domestic cat strain and treated with the anticoccidial diclazuril (group DC-D); and (5) infected with T. gondii domestic cat strain and treated with the medicinal plant Artemisia annua (group DC-A). Clinical signs, body temperature, mortality rate, weight gain, feed conversion ratio, hematological parameters, and the presence of T. gondii-specific IgY antibodies were recorded in all groups. Five chickens per group were euthanized 28days post-infection (p.i.) and their brains, hearts, and breast muscle tested for T. gondii by mouse bioassay and polymerase chain reaction (PCR). No clinical signs related to the experimental infection were observed throughout the study period. T. gondii-specific antibodies were detected by day 28 p.i., but not in all infected chickens. Overall, T. gondii DNA was detected (bioassay or tissue digests) in all infected and untreated chickens (10/10), while viable parasite (bioassay) was isolated from 7 out of 10 chickens. The parasite was most frequently identified in the brain (7/10). There were no differences in the T. gondii strains regarding clinical infection and the rate of T. gondii detection in tissues. However, higher antibody titers were obtained in chickens infected with T. gondii WC strain (1:192) comparing with T. gondii DC strain (1:48). A. annua reduced replication of the parasite in 3 out of 5 chickens, while diclazuril did not. In conclusion, broiler chickens were resistant to clinical toxoplasmosis, irrespective of the strain (domestic or wild cat strain). The herb A. annua presented prophylactic efficacy by reduced parasite replication. However, further studies are required aiming at the efficacy of diclazuril and A. annua for the prevention of T. gondii infection in chickens using quantitative analysis methods.

Efficacy of diclazuril and toltrazuril in the prevention of coccidiosis in dairy calves under field conditions

A blinded, controlled, randomised field study was undertaken on two commercial dairy farms in Germany to compare the efficacy of the anticoccidials, diclazuril and toltrazuril in the prevention of bovine...

Scientific Opinion on the safety and efficacy of diclazuril (Clinacox® 0.5 %) as feed additive for chickens reared for laying

Clinacox® 0.5 % is a feed additive containing 0.5 % diclazuril and is used to control coccidiosis in poultry. The previous conclusion on the safety of diclazuril in chickens for fattening at the use level of 1 mg/kg complete feed is extended to chickens reared for laying. Chickens reared for laying are in a similar physiological stage as chickens for fattening. The use level proposed for diclazuril in feed is the same for both categories of birds. Consequently, the metabolic fate and residue status of this additive described for chickens for fattening can be extrapolated to chickens reared for laying. Feeding diclazuril at 1 mg/kg complete feed to chickens reared for laying for the first 16 weeks of life would result in negligibly low or absent residues of diclazuril in the first eggs for production. Therefore, maximum residue levels (MRLs) for eggs are not necessary. The previous assessment of consumer safety for the use of diclazuril in chickens for fattening is confirmed and extended to chickens reared for laying. The same MRLs for tissues as already established can be applied. Clinacox® has a low irritation potential for the eye and skin. Skin sensitisation was not observed. Considering the particle size (particle of respirable size) and dusting potential, exposure by inhalation cannot be excluded, although workers’ exposure has been calculated to be low in comparison with the ADI. In the absence of any data on respiratory toxicity, a hazard from inhalation of dust cannot be entirely excluded and appropriate protective measures should be taken. The use of Clinacox® at 1 mg/kg complete feed does not pose a risk to the terrestrial or aquatic environment. One mg diclazuril/kg complete feed is effective in controlling coccidiosis in chickens reared for laying.

Activity of diclazuril against coccidiosis in growing rabbits: experimental and field experiences

The efficacy of diclazuril in growing rabbits was investigated under experimental and field conditions. In a first experimental trial, the susceptibility of recent isolated French Eimeria field strains to in-feed use of diclazuril, salinomycin and robenidine was studied in fattening rabbits. Rabbits were challenged at the age of 31 d with a mixed inoculum of Eimeria magna, E. media and E. perforans. Production data and oocyst excretion were compared with an infected-untreated control group and an uninfected-untreated control group. Infection resulted in significantly lower production data and higher oocyst excretion in the infected-untreated control group. Salinomycin and diclazuril treated rabbits were able to control the infection, demonstrated also by comparable weight gain and final weight to those of the uninfected-untreated control rabbits and significantly higher than those of the infected-untreated control rabbits. Based on the production data and oocyst excretion, robenidine was not able to control the infection adequately. Economic performance (weight gain, feed intake, feed conversion) and oocyst excretion were significantly worse than in the uninfected-untreated controls. In a second trial, a 1 yr longitudinal study was carried out in Italy to evaluate the excretion of coccidia in growing rabbits from 8 meat farms applying a 2-phase anticoccidial programme (diclazuril and robenidine). Parasitological parameters (oocyst counts and species identification) were measured monthly. Seven of the 11 known coccidial rabbit species were identified. Variable levels of oocysts per gram were detected in the farms, but on all farms lower oocyst per gram and a reduced number of Eimeria spp. in rabbit faeces were recorded in the 8-mo treatment period with diclazuril.

THE EFFECT OF DICLAZURIL AND MADURAMICIN ALONE OR TOGETHER IN CONTROLLING CECAL COCCIDIOSIS IN CHICKENS

Coccidiosis in chicken farms are considered as one of the most serious problems affecting both small and large poultry producers. Eimeria tenella now is consider as one of the most pathogenic and important Eimeria species affecting about 90% of intensive broiler production. This study was carried out to evaluate the efficacy of maduramicin (5ppm), diclazuril (2.5ppm) and both drugs together on healthy and experimentally infected chicken with E.tenella (50000 sporulated oocyst) on 15th day of age after the symptoms of infection had appeared on 5th day of infection for 3 successive days from 20th day to 22nd day and from 30th day to 32nd day of age. The results revealed that the infected group treated with both of maduramicin and diclazuril did not show any antagonistic interaction between them but leading to the best results among all infected treated groups by overcome clinical signs, decrease mortality rate, lesion scoring, give the lowest count of oocyst shedding and represented the best improvement in biochemical parameters throughout the experiment. This reflects the synergistic interaction between them without any significant adverse effect. The efficacy of diclazuril was superior to maduramicin in treatment of cecal coccidiosis by marked improvement on cecal integrity and reduction of the oocyst shedding. Non infected treated groups did not show any significant difference than negative control group during the experimental period and this reflects the safe use of both drugs either individually or together

The efficacy of diclazuril (liquid formulation) in the prevention and control of coccidiosis in broiler chicken.

This study was carried out to evaluate the efficacy of water soluble formulation of diclazuril (1%) in the prevention and control of mixed Eimeria infection in two experimental (semifield) trials and testing efficacy of this medicament in controlling of natural field case of mixed Eimeria infection. The experimental (semifield) trials carried out each on 150-day-old broiler chicks, as they were divided into 3 equal separate subgroups. Infected groups were orally received 1ml of an inoculum containing 50.000 sporulated oocysts of Eimeria tenella, E. acervulina and E. necatrix/ chick at 14 days of age. Diclazuril (1%) liquid at dose of 1 ml / 4 liter of drinking water for 2 successive days just after appearance of bloody dropping (at the 5th day post infection). Birds were given prophylactic diclazuril dose (1 ml / 8 liter) at the 7th day before the experimental inoculation. In both trials were oocyst count (shedding) in the dropping, dropping score, lesion score, body weight gain % and mortality rate were evaluated. Groups treated with diclazuril either in the prophylactic and curative studies gave significant and satisfactory improvement in the assessment criteria when compared with infected non medicated groups. A field trial was conducted 2 commercial broiler chicken farm consisted of 2 flocks aged 33 days; 6000 birds each. Flock (1) was kept as control positive infected non medicated group, whereas flock (2) was medicated with diclazuril (1%) at dose of 1 ml / 4 liter of the drinking water for 2 successive days. The results revealed more reduction in total oocyst count, lesion score and the mortality rate in the medicated than the infected non-treated group. The results proved that diclazuril (1%) liquid is effective in prevention and control of both experimental and field infection field circulating Eimeria species still sensitive to the drug.

Efficacy of Diclazuril in Comparison with Chemical and Ionophorous Anticoccidials Against Eimeria spp. in Broiler Chickens in Floor Pens

Two 42-d floor pen studies were conducted with commercial broiler chickens to measure the efficacy of 1 ppm diclazuril in the starter or grower diet in shuttle programs with 66 ppm salinomycin. Study 1 compared a salinomycin to diclazuril (starter to grower diet) shuttle treatment with salinomycin to salinomycin, salinomycin to 100 ppm monensin, salinomycin to 99.8 ppm lasalocid, and unmedicated treatments. Study 2 compared a diclazuril to salinomycin (starter to grower) shuttle treatment with 125 ppm nicarbazin to salinomycin, 79.2 ppm narasin + nicarbazin to salinomycin, 125 ppm zoalene to salinomycin, and unmedicated treatments. Fifty 1-d-old chicks were randomly allotted to each of 10 pens per treatment in each study using a randomized complete block design. Starter (Days 0 to 21) and grower (Days 22 to 37) diets in each study contained 55 ppm bacitracin methylene disalicylate. The finisher diet (Days 38 to 42) in each study was unmedicated. Birds were inoculated via their feed on Day 22 (Study 1) or Day 15 (Study 2) with a mixed inoculum of Eimeria acervulina, Eimeria maxima, and Eimeria tenella. Four birds per pen (two male and two female) were randomly selected in each study for coccidial lesion scores on Day 6 postinoculation. These studies demonstrated that the use of 1 ppm diclazuril in shuttle programs was highly efficacious against a mixed inoculum of Eimeria spp. in comparison with nicarbazin, narasin + nicarbazin, and zoalene in starter diets and salinomycin, monensin, and lasalocid in grower diets.

Efficacy of Diclazuril against Eimeria dispersa in Turkeys

Diclazuril, a new anticoccidial drug, was tested for its efficacy against Eimeria dispersa in turkeys. A dose-titration study indicated that diclazuril at dosages of 0.5, 1, and 2 ppm in the feed was highly effective in terms of weight gain and suppression of lesions, abnormal droppings, and oocyst shedding.

Anticoccidial efficacy of diclazuril in pheasants.

Diclazuril, a new anticoccidial drug, was tested in young pheasants artificially infected with the three most common pathogenic species of Eimeria, E colchici, E duodenalis and E phasiani. In two replicate experiments each with 40 birds the mortalities in the infected controls were 50 and 25 per cent. Diclazuril was administered in the feed at dose levels of 1, 2 and 4 ppm from the day before the inoculation of coccidia until the end of the test on day 6 after infection. The 1 ppm dose failed to inhibit the development of the parasite completely, as was shown by a reduction of the weight gain of the birds and the output of a small number of oocysts. Diclazuril at 2 or 4 ppm adequately controlled the infection, with weight gains similar to those of the uninfected controls. At all dose levels, mortality, intestinal lesions and diarrhoea were prevented.

Efficacy of diclazuril in the prevention and cure of intestinal and hepatic coccidiosis in rabbits

The efficacy of diclazuril against intestinal and hepatic coccidiosis was studied in artificially infected rabbits. Prophylaxis against intestinal coccidiosis was evaluated using a mixed infection of Eimeria intestinalis, Eimeria magna and Eimeria perforans. Continuous medication in the feed at 1 p.p.m. was 100% effective in reducing oocyst output and faecal scores, and weight gain and feed efficiency were normal. Hepatic coccidiosis induced by Eimeria stiedai was prevented at 0.5 and 1 p.p.m. as shown by negative oocyst counts, normal liver weight, absence of liver lesions, and normal body-weight gain and feed efficiency. Medication at 1 p.p.m. for 7 consecutive days during the prepatent phase of hepatic coccidiosis resulted in large reductions in oocyst counts and lesion scores with a normal liver weight and growth performance. Diclazuril at 1 p.p.m. in the feed prevented both intestinal and hepatic coccidiosis in rabbits and can be advocated for safe mass medication.

Efficacy of Diclazuril against Turkey Coccidiosis in a Floor-Pen Experiment

Diclazuril, a new anticoccidial drug, was tested for its efficacy in turkeys against mixed Eimeria infections. A floor-pen trial indicated that diclazuril at dosages of 0.5 ppm and 1 ppm in the feed was highly effective against the major pathogenic species E. adenoeides, E. gallopavonis, and E. meleagrimitis in suppressing intestinal and cecal lesions and oocyst shedding. Weight gain and feed conversion improved, particularly at 1 ppm.

Efficacy of diclazuril against robenidine resistant Eimeria magna in rabbits.

Efficacy of diclazuril against robenidine resistant Eimeria magna in rabbits.