Efficacy of a morantel sustained-release bolus for control of gastrointestinal parasites in winter-grazed steers in Mississippi.

Abstract

From Nov 22, 1983 through May 15, 1984, 36 crossbred steers were allotted into 3 treatment groups (12/group) and were grazed on separate 3.4-hectare pastures. On Nov 22, 1983, the steers were administered a single morantel sustained-release bolus (MSRB), orally (group 1), or a single dose of thiabendazole (TBZ; 66 mg/kg of body weight, orally; group 2), or were left untreated (group 3; controls). Animal weights, nematode egg counts in fecal specimens, and plasma pepsinogen concentrations were monitored monthly. At the termination of the study, 4 steers from each treatment group were slaughtered and necropsied and worm counts were determined. A set of parasite-free tracer calves (3/treatment group) were grazed with each treatment group for 1 month, beginning on Nov 22, 1983; a second set of tracer calves (3/group) were grazed with each treatment group for 1 month, beginning Apr 3, 1984. At the end of their respective grazing periods, tracer calves were held for 3 weeks and then were slaughtered and necropsied and their worm counts were determined. Mean nematode egg counts in fecal specimens of group 1 (MSRB treated) were significantly lower (P less than 0.05) than that of the TBZ-treated or nontreated steers. Differences in worm counts were not found between treatment groups. Differences in worm counts of tracer calves were not found among the 3 groups for November 1983 nor for April 1984. Steers treated with the MSRB had a higher mean weight gain (P less than 0.06) than did the control or TBZ-treated steers.

• Authors: J A Hawkins, R R Evans, C E Taylor, C E Couvillion, E F Illyes, C P Wilkins, M H Johnson-Delivorias, T D Tyler
• Journal: American journal of veterinary research (Am J Vet Res) Vol. 48 Issue 5 Pg. 848-51 (May 1987) ISSN: 0002-9645 [Print] United States
• PMID: 3592388 (Publication Type: Comparative Study, Journal Article)

Chemical References

• Delayed-Action Preparations
• Pyrimidines
• Morantel
• Thiabendazole

Topics

• Animals
• Cattle
• Cattle Diseases (parasitology, prevention & control)
• Delayed-Action Preparations
• Gastrointestinal Diseases (parasitology, prevention & control, veterinary)
• Intestinal Diseases, Parasitic (prevention & control, veterinary)
• Male
• Mississippi
• Morantel (therapeutic use)
• Pyrimidines (therapeutic use)
• Thiabendazole (therapeutic use)