Enzyme-linked immunoelectrotransfer blot analysis of excretory-secretory proteins of Fascioloides magna and Fasciola hepatica

Fasciola hepatica is a parasite of cattle (Bos taurus), but not of white-tailed deer (Odocoileus virginianus), while Fascioloides magna is a parasite of white-tailed deer which also infects cattle as dead-end host. Adult parasites were collected from naturally infected white-tailed deer or cattle. Excretory-secretory proteins (ESP) were obtained from each parasite. Protein banding patterns were analysed on sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) and probed using sera from experimentally infected deer of cattle using enzyme-linked immunoelectrotransfer blot (EITB, also known as Western blot) analysis. Protein banding patterns of the two species were different. EITB analysis of Fascioloides magna ESP using sera from Fascioloides magna infected deer or cattle identified three bands of approximately 17, 22 and 27 kDa of which the 27 kDa antigen cross-reacted with sera from Fasciola hepatica infected cattle. EITB analysis of Fasciola hepatica ESP probed with sera from Fasciola hepatica infected cattle identified three bands of approximately 15, 26 and 46 kDa. The 46 and 26 kDa ESP cross-reacted with sera from Fascioloides magna infected cattle, but not with sera from Fascioloides magna infected deer. The band at 15 kDa which reacted specifically for Fasciola hepatica infected cattle sera consisted of two protein bands close to each other as seen on the SDS-PAGE gel. The EITB reaction at approximately 17 kDa and 22 kDa of Fascioloides magna ESP, and at approximately 15 kDa of Fasciola hepatica ESP can be used for species specific diagnosis.

Use of bait containing triclabendazole to treat Fascioloides magna infections in free ranging white-tailed deer

Triclabendazole-medicated corn bait was given to white-tailed deer (Odocoileus virginianus) on the Welder Wildlife Refuge, Sinton, Texas (USA), at a dose of 11 mg/kg body weight per deer per day for seven days, for control of Fascioloides magna. Medicated bait was offered for one week each during the winters of 1987, 1988, and 1989. Deer collected from treated areas, from baited control and from unbaited control areas were examined before the start of the study in 1987, and four weeks after the end of the baiting period in each of three years. Prior to the study, prevalence of fluke infection was 68%. After treatment with triclabendazole medicated corn, 13 (56%) of 23 deer collected were infected with flukes of which 15% had live parasites; this was evidence for therapeutic treatment. Of the deer collected in the baited and unbaited control areas, 63% and 80%, respectively, were infected only with live flukes. Prevalence of live flukes in deer was significantly (P < 0.05) lower in the treatment pasture than in the baited or unbaited control areas in each of the three years. Efficacy of the baiting system over the three years was 63% when comparing the treatment area and the baited control area.

Use of albendazole in feed to control Fascioloides magna infections in captive white-tailed deer (Odocoileus virginianus)

Thirty-six adult white-tailed deer (Odocoileus virginianus) naturally infected with Fascioloides magna were captured and randomly assigned to four groups. Each group was fed pelleted feed coated with albendazole for each of seven consecutive days to deliver the drug at a dose rate of approximately 0.0, 5.0, 8.5, or 16.5 mg/kg bodyweight/day. At 7 wk posttreatment, each animal was euthanized and necropsied. Effects of albendazole treatment included significant reduction (P less than 0.05) in parasite egg count per gram of feces and increase in serum albumin concentration (P less than 0.05). Smaller parasites or remains of dead parasites were seen at the end of migratory tracks in the treated groups. Efficacy of the drug was 82 to 84%.

Efficacy of triclabendazole against fascioloidiasis (Fascioloides magna) in naturally infected white-tailed deer (Odocoileus virginianus)

The efficacy of triclabendazole was evaluated in the treatment of naturally acquired Fascioloides magna infections in white-tailed deer (Odocoileus virginianus). Twenty white-tailed deer were captured on the Welder Wildlife Refuge (Sinton, San Patricio County, Texas, USA) and maintained in a 64 x 64 m deer enclosure. Ten deer were given a 5% suspension of triclabendazole orally at a dosage of 10 mg/kg body weight and 10 deer were given a placebo. Three wk later the deer were euthanized and examined for parasites. At necropsy 19 deer were infected. All specimens of F. magna from the tissues of the triclabendazole treated deer were dead or severely affected by the drug as indicated by changes in their size, color, movement and texture relative to those from control deer. The drug was considered 100% effective against this parasite. Adverse reactions of the deer to the drug were not observed.

Efficacy of clorsulon and albendazole against Fascioloides magna in naturally infected white-tailed deer

The efficacy of clorsulon and of albendazole against Fascioloides magna were evaluated in 36 naturally infected white-tailed deer (Odocoileus virginianus) in southern Texas. A single oral dose of clorsulon suspension (12 to 30 mg/kg of body weight; mean = 24 mg/kg) was given to each deer and killed 153 (92%) of 167 mature flukes and 4 (80%) of 5 immature flukes recovered at necropsy. A single oral dose of albendazole paste (17 to 46 mg/kg; mean = 26 mg/kg) was given to each deer and killed 148 (89%) of 167 mature flukes and 4 (67%) of 6 immature flukes recovered at necropsy. In 82 nontreated control deer, 271 live flukes were recovered; dead flukes were not recovered.

Anthelmintic activity of albendazole in white-tailed deer

Albendazole at dose rates of 11 to 54 mg/kg (mean of 25 +/- 11 SD) of body weight was highly effective (greater than 99%) against Haemonchus contortus, Ostertagia odocoilei, O mossi, Trichostrongylus askivali and Nematodirus odocoilei in 22 white tailed deer (Odocoileus virginianus) in southern Texas. It was 38% effective against mature and immature deer liver flukes (Fascioloides magna). Toxicoses associated with treatment were not observed. Large numbers of abomasal nematodes (mean of 2,949 +/- 3.147 SD) were recovered from 16 untreated control deer, indicating these may have had a potential impact on herd health and indicating the importance of treatment or other management alternatives.