Treatment efficacy and regulatory host responses in chronic experimental Schistosoma bovis infections in goats

• Published in: Parasitology 2006-08, Vol.133 (2), p.151-158
• Main Authors: MONRAD, J., SÖRÉN, K., JOHANSEN, M. V., LINDBERG, R., ØRNBJERG, N.
• Format: Article
• Language: English
• Subjects: Animals; anthelmintics; Anthelmintics - therapeutic use; Biological and medical sciences; Body weight; Cattle; Chronic Disease; chronic infection; chronic infections; disease resistance; drug efficacy; Egg production; Eggs; experimental infection; fecal egg count; Feces - parasitology; Fundamental and applied biological sciences. Psychology; General aspects; General aspects and techniques. Study of several systematic groups. Models; Goat Diseases - drug therapy; Goats; hemoglobin; Hemoglobins - analysis; immune response; Invertebrates; lesions (animal); Liver; Liver - parasitology; Liver - pathology; liveweight gain; Male; Mammalia; Parasite Egg Count; Parasitology; praziquantel; Praziquantel - therapeutic use; praziquantel treatment; Production capacity; Random Allocation; resistance; Schistosoma; Schistosoma bovis; schistosomiasis; Schistosomiasis - drug therapy; Schistosomiasis - veterinary; Studies; Tissues; Treatment Outcome; Vertebrates: general zoology, morphology, phylogeny, systematics, cytogenetics, geographical distribution; Weight Gain; West African Dwarf (goat breed); worm burden; Worms
• ISSN: 0031-1820; 1469-8161
• DOI: 10.1017/S0031182006000102

The aim of this study was to elucidate the regulatory responses and the long-term effect of praziquantel treatment in chronically Schistosoma bovis-infected West African Dwarf goats. Forty-two goats were used and the design comprised a primary infection followed by treatment at week 13, challenge infection at week 36 and termination at week 52. Dependent variables included clinico-pathological data, worm numbers, faecal and tissue egg counts, and gross pathology of the liver. The results showed that primary infections remained suppressed for up to 52 weeks and, although challenge infections imposed on 36-week-old primary infections established fully, the impairment of their egg production capacity provided protection against clinico-pathological consequences measured by body weight and haemoglobin levels. The study also confirmed a high efficacy (97·7%) of praziquantel for treatment of S. bovis infection in goats and showed that anthelminthic removal of primary infections does not interfere with the ability of the goat to elicit a marked resistance to a subsequent challenge infection. Although treated goats had more fibrous scarring of livers than untreated goats, no negative effects of liver lesions were reflected in weight gains of treated goats. This study provides strong evidence for the beneficial effects of anthelminthic treatment of young domestic stock as an element of treatment and preventive programmes.