Evaluation of the Fasciolicidal/Nematicidal Efficacy of an Intramuscular Combination of Clorsulon/Levamisole in Naturally Infected Dairy Cattle

The aim of the present study was to assess the fasciolicidal and nematicidal efficacy of a new combination of clorsulon/levamisole, which was formulated for intramuscular administration, in dairy cattle. For the study, sixteen Holstein-Freisian dairy cows were selected for inclusion in the trial based on finding Fasciola hepatica eggs or gastrointestinal nematodes (GIN) in the feces. Ten of these cows were naturally infected with F. hepatica, and 6 were naturally infected with GIN. On Day 0 (zero), all animals were treated with a combination of clorsulon (2.5 mg/kg/IM and levamisole (2.5 mg/kg/IM) administered at the dose recommended by the manufacturer (1 ml/20kg/bw). Subsequently, their feces were analyzed on days 0, 7, 14 and 21 post treatments by the Flukefinder sedimentation method and McMaster technique to determine the percentages of egg reduction in the animals, with reference to the egg load count on day 0. The results obtained in the current work indicated an efficacy of 100% that was determined by the percentage reduction of eggs of F. hepatica and/or GIN. This new fasciolicide/nematicide formulation exerted a remarkable effect and can be considered a new alternative to control F. hepatica and gastrointestinal worms in dairy cattle.

Additive Efficiency of Fipronil + Methoprene Compared to Fipronil Alone against <i>Rhipicephalus sanguineus</i>Ticks in Naturally Infested Dogs

The acaricidal efficiency of fipronil alone and fipronil + methoprene compared to commercial fipronil and commercial fipronil + methoprene, applied by the epicutaneous route (spot-on) in dogs naturally infested with ticks, was assessed. Thirty dogs infested with high loads of ticks were used. On day 0, the dogs were divided into 5 groups of 6 animals each. Each animal was duly identified for individual and group monitoring. Treatments were made based on body weight according to manufacturer’s instructions. Group 1 (G1) received 10.0% fipronil at a single dose of a pipette applied by epicutaneous route in the base of the neck. G2 received 10% fipronil + 10% methoprene in single application similarly to G1. G3 was treated with 9.8% commercial fipronil as before mentioned. G4 received commercial 9.8% fipronil + 9.8% methoprene applied as in previous groups. G5 served as an infected untreated control. Animals were examined by thumb tick counts on days 0 (Treatment day), 3, 7, 14, 21 and 28. Efficacy was measured as a percentage of tick reduction in the treated groups relative to the untreated control. Results indicated an overall efficacy of 88.2%, 93%, 90.4% and 99.3%, respectively. There was no significant statistical difference between the treated groups (P < 0.05), neither in sex nor in weight. Engorged ticks were the most frequent, followed by the nymph group. However, by the end of the study these data were reversed due to the fact that only small larvae were found, which we interpreted came from engorged ticks that released their progeny before dying and a month later their offspring began to be observed presently and in full development. It is concluded that the combined formulations of fipronil + methoprene compared to fipronil applied alone, showed an additive effect against Rhipicephalus sanguineus ticks in naturally infested dogs kept in captivity.

Maximum Entropy Ecological Niche Prediction of the Current Potential Geographical Distribution of <i>Eimeria</i>Species of Cattle, Sheep and Goats in Mexico

Coccidiosis is a gastrointestinal disease caused by parasites of the genus Eimeria. To produce the ecological niche model for the geographic distribution of Eimeria species, the maximum entropy algorithm (MaxEnt) was used and 19 bioclimatic variables with a spatial resolution of 30 arc-seconds (approximately 1 km2) were downloaded from the World Climate Database. These were reduced to BIO2, BIO3, BIO4, BIO7 and BIO15 for each species after examining cross-correlations among them to account multicollinearity. A jackknife analysis was included to assess the contribution of five bioclimatic variables and the fit of the model was evaluated with the area under receiver operating characteristic curve (AUC). Under a current climate scenario, the jackknife evaluation of the MaxEnt model showed that BIO4 (temperature seasonality) made the greatest contribution to the distribution model for 22 Eimeria species;whereas BIO7 (temperature annual range) was the most important factor that contributes to the distribution model of 10 species. The habitat suitability model based on the maximum entropy theory was supported by AUC values higher than 0.9 and predicted that the suitable habitats for different species of Eimeria are present in southern, eastern and western areas of Mexico. Our study may support future studies exploring factors that constrain the distribution of Eimeria as well as strategies aimed at reducing the disease prevalence.

Comparison of Two Pour-On Formulations of Ivermectin against Gastrointestinal Worms, Fleas and Lice in Naturally Infected Stray Dogs

The aim of the present study was to evaluate the efficacy of two commercial pour-on ivermectin formulations against intestinal parasites (IP), fleas and lice in naturally infested stray dogs. Eighteen crossbreed dogs with eggs of IP as well as adult fleas and lice were included in the trial. On day 0, the dogs were randomly divided into 3 groups of 6 animals each: a group receiving a single pour-on treatment with 0.5% ivermectin (500 mcg/kg), a group treated similarly with 0.2% iver-mectin (200 mg/kg), and a control group. Fecal and skin analyses were carried out on days 0, 7, 14, 21 and 28 to determine the reduction of eggs and the number of fleas and lice. Weight gain was also measured on day 28. On day 30, the dogs were humanely sacrificed in order to count adult IP. Efficacy was measured as the percentage of the reduction of eggs per gram fecal mass (EPGF), of adult IP, fleas and lice relative to the control group. For the eggs of IP, ivermectin at 0.5% showed an efficacy of 100% against ascarids and 79% against Ancylostoma caninum. ivermectin at 0.2% removed 90.2% of the ascarids and 50.4% of A. caninum. For adult IP, the efficacy of 0.5% iver-mectin against Toxocara canis and A. caninum was 100%, and for 0.2% ivermectin it was 62.4% and 76.4% for T. canis and A. caninum, respectively. Both compounds were 100% effective against lice and 96% and 71.1% efficacious against fleas, respectively. However, neither treatment was effective against Dypilidium caninum. Weight gain in treated dogs was statistically different from that of the controls (p < 0.05). We concluded that 0.5% pour-on ivermectin showed better efficacy than 0.2% pour-on ivermectin in the reduction of eggs and adult intestinal parasites and fleas;it was similarly efficacious against lice.

Comparison of the Anthelmintic Efficacy of Three Commercial Products against Ascarids and Capillaria SPP. in Fighting Cocks

The aim of the present study was to evaluate the anthelmintic efficacy of three commercial compounds against ascarids and Capillaria spp. in naturally infected fighting cocks from Mexico. First experiment.- Forty cocks were selected on the basis of eggs per gram (EPG) counts quantified by the McMaster method. On day 0 the birds were divided into four groups of 10 cocks, each subjected to the treatments. Group 1 received a single oral dose of 1 mg of ivermectin, 25 mg of praziquantel and 40 mg of fenbendazole given in tablets according to body weight (b.w). Group 2 was treated with a single oral dose of 1 mg of ivermectin, 25 mg of praziquantel and 40 mg of fenbendazole given in tablets/b.w. but formulated with a different excipient. Group 3 received a single tablet containing 0.2 mg of abamectin and 30 mg of albendazole. Group 4 served as a non-treated control. Fecal analyses were carried out on days 0 (day of treatment), 7, 14, 21 and 28, being collected from the floor where the cocks were individually caged. Efficacy was measured on the percentage of egg reduction from day 0 with respect the EPG counts from the control group. In a second experiment the study was similarly performed using another cock-farm located at approximately 300 km away from the first one. Results indicated an overall efficacy of 100%, 94.0% and 100% for groups 1, 2 and 3 in the first experiment and 100%, 100%, 100% for groups 1, 2 and 3 of the 2nd experiment, respectively. It is concluded that all drugs used exerted high efficacy in fighting cocks naturally infected with helminths.

Comparative Efficacy of Three Commercial Ectoparasiticides against Fleas in Naturally Infested Dogs

Fleas that infest pets are considered important parasites of both animals and humans. These insects cause irritation and can also transmit zoonotic diseases. Research has led to a rapid expansion in the development of flea control products. In the face of a market that offers dozens of commercial ectoparasiticides for dogs and cats, pet owners and veterinarians must be provided with evidence to support their decision to select a product to control fleas. To compare the efficacy of three commercially available products against companion animal fleas, a trial was conducted on naturally-infested dogs in order to validate their pulicidal activity. Thirty-two flea-infested dogs with fleas were divided into 4 groups (n = 8) for each treatment. Group 1 received one pipette of permethrin as a spot-on dose of 650 mg/ml. The second group received 9.7% fipronil as a spot-on formulation. Group 3 was treated with a spot-on formulation of permethrin 7.40% plus piperonyl butoxide at 7.40%. Group 4 remained as the untreated control. Fleas of all experimental dogs were examined and counted on days 0, 3, 7, 14, 21 and 28 to determine the percentage of flea reduction. Results showed a 100% efficacy for all tested products. Identified species were: Ctenocephalides felis (75.7%), Ctenocephalides canis (15.9%) and Pulex irritans (9.5%). Based on these results, it was concluded that the three anti-flea products evaluated under the conditions of this study, produced an excellent efficacy as from the third day after treatment.

Effectiveness of the Experimental Fosfatriclaben in Comparison with Two Commercial Fasciolicides in Cattle

The aim of the present study was to compare the fasciolicidal efficacy in cattle of an experimental water-soluble compound, named fosfatriclaben, a prodrug of triclabendazole, with two commercial fasciolicides. For this, twenty-four cross mixed milking cows, aged between 1 to 3 years, naturally infected with Fasciola hepatica, were used. To apply the treatment, animals were divided into 4 groups of 6 animals each being ranked according to their fecal fluke-egg count from the highest to the lowest number of eggs. The compounds were administered in the groups with a single dose. Group 1 (G1) was treated with 6 mg/kg/IM of fosfatriclaben, G2 was treated with triclabendazole at 12 mg/kg/PO;G3 was treated with 5% closantel at 10 mg/kg/SC and G4 was administered with 5 mL/IM of deionized water and served as untreated control. Fecal samples were analyzed on days—8, 0 (treatment day), 7, 14, 21 and 28 to count the number of fasciola eggs before and after the treatment using the sedimentation test. The efficacy was assessed as the percentage of fluke-egg reduction on treated groups relative to the untreated control. The resulting data were analyzed by the Kruskal-Wallis non-parametric test, using the statistical IBM SPSS 24.0 (2016) program. Results indicated a fluke-egg reduction of 100% for fosfatriclaben along the study;triclabendazole showed an efficacy of 99.7% - 100% from day 7 to day 28. In the case of closantel, values from 98.8% to 99.6% were recorded from day 7 to day 28. No statistical differences between treatments were observed (P < 0.05). It was concluded that the experimental fosfatriclaben administered at 6 mg/kg/IM to naturally infected cattle exerted a fasciolicidal efficacy similar to the drugs of choice for the treatment of fasciolosis (triclabendazole) when administered at 12 mg/kg/ PO, and closantel injected at 10 mg/kg/SC.

Comparison of the Efficacy of Two Commercial Coccidicidal Compounds on Experimentally Infected Dogs

The aim of the present study was to compare the coccidicidal efficacy of two commercial compounds for artificially infected dogs. Eighteen cocccidia-free dogs, male and female aged between 2 and 4 months old, were infected each with 20,000 Cystoisospora oocists cultured under laboratory conditions. When the poppies showed high counts of oocysts per gramm (OPG) (McMaster method), they were divided into 3 groups (G). G1 was treated with a compound named One&reg (Lab. Bio Zoo) containing 150 mg of toltrazuril/tablet, administered daily/5days dosing 1 tablet per 10 kg b.w. G2 received Giacoccide&reg (Pet’s Pharma) containing 250 mg of sulfadimetoxine and 165 mg of dimetridazole dosing 1 tablet per 10 kg b.w. twice a day for 10 days. G3 served as an untreated control. The puppies were coprologically monitored on Days 0, 3, 5, 10, 15, 20 and 25 to determine the percentage of OPG. Efficacy was measured based on the OPG reduction on treated animals relative to the untreated control. The results indicated an efficacy for compound One of 78.4%, 100%, 100%, 100%, 100% and 100%, for Days 3, 5, 10, 15, 20 and 25, respectively and for Giacoccide 40.6%, 45.5%, 47.4%, 65.9%, 90.4% and 92.7%, for Days 3, 5, 10, 15, 20 and 25, respectively. No statistical difference was observed on the weight of the treated puppies (p < 0.764), but the control group was statistically different to the treated ones (p < 0.014). It was concluded that compound One showed greater efficacy than Giacoccide for the treatment of canine coccidiosis in artificially infected dogs.

<i>In Vivo</i>and <i>in Vitro</i>Evaluation of Permethrin, Cypermethrin or Zeta-Cypermethrin Mixed with Plant Extracts against Susceptible and Resistant (San Alfonso) <i>Rhipicephalus (Boophilus) microplus</i>(Acari: Ixodidae) Strains

Acaricide resistance is a major problem that hinders the control of the cattle tick Rhipicephalus (Boophilus) microplus in Mexico. Permethrin (P), cypermethrin (C) and zeta-cypermethrin (Z) have been used to control R. (B.) microplus, and tick populations have developed resistance to these acaricides. The aim of the present study was to evaluate the effectiveness of a mixture containing P, C, or Z mixed with plant extracts through in vitro laboratory bioassays, using susceptible and triple resistant (San Alfonso) R. microplus strains. Untreated controls received only water. Results of laboratory bioassays using larval packet tests revealed an efficacy of 100% (P), 100% (Z), and 98.03% (C) using susceptible larvae, and an efficacy of 88.67% (P), 91.51% (C), and 99.27% (Z) on triple-resistant larvae. Egg laying, larvae hatching and efficacy was assessed using ticks collected from treated and untreated animals. Product Z produced a 92.04% efficacy on engorged ticks collected from experimentally-infested cattle, whereas C and P exerted 80.66% and 20.04% efficacy, respectively. Engorged females collected exclusively from control animals were challenged in vitro with the experimental products, and efficacy was as follows: 91.37% (Z), 85.95% (C), and 13.58% (P). Adding plant extracts to a pyrethroid formulation led to dramatic increases of percent reduction of both susceptible and resistant immature ticks in contrast to untreated larvae and susceptible adults. Results from this study may lead to suggesting the adoption of an acari-cide-botanical mixture strategy for tick control worldwide.