Oxfendazole treatment of non-parasitized lambs and its effect on the immune system

Abstract

Ten parasite-free lambs were drenched with oxfendazole on days 0 and 28 and, one day after each drench, were injected with human erythrocytes and ovalbumin. Ten other antigen-injected lambs were not drenched (controls). Lymphocytes collected 3 days after each antigen injection and cultured in RPMI 1640 plus 5% fetal calf serum (FCS) and lymphocytes collected 3 days after the first and 3 and 7 days after the second antigen injection and cultured in 50% autologous serum had decreased blastogenic activity compared with control lymphocytes. After the second drench, decreased blastogenesis was seen with lymphocytes collected on days 3 and 7 and cultured in 5% FCS and concanavalin A (Con A) and on day 3 when cultured in 5% FCS and phytohaemagglutinin (PHA). Decreased blastogenesis was also seen with lymphocytes collected 7 and 29 days after the second injection of antigen and cultured in 50% autologous serum plus Con A and on days 3, 7 and 29 when cultured in 50% autologous serum and PHA. Significantly depressed antibody responses to both antigens were seen after the second drench. The serum complement level was depressed 3 days after the second injection of antigen. Serum nitric oxide levels were significantly depressed 3 and 21 days after the first and 7 and 21 days after the second injection of antigen. There were no differences in levels of growth-promoting hormones but the drenched lambs gained significantly more weight than the controls.

Oxfendazole Treatment of Sheep with Naturally Acquired Hydatid Disease

“…However, this hypothesis is difficult to substantiate, given the low number of animals in the daily group and the lack of relevant clinical parameters on those animals that died. These results do parallel unexplained findings in a recent study in which oxfendazole-drenched lambs (two doses of 4.5 mg/kg) gained significantly more weight than the controls with no difference in levels of growth-promoting hormones (24). Increased intestinal parasite loads in the controls relative to treatment groups do not explain these weight gain differences, because the daily group weight gain was four times that of any other treatment group; monthly or weekly dosing should have effectively controlled intestinal parasites in these groups.…”

“…In another study, 2 of 10 sheep died of acute septicemia or pneumonia with bone marrow depression following daily treatment with albendazole (19). Recent work with oxfendazole in parasite-free lambs suggests that oxfendazole may depress humoral and cellular immunity even at much lower doses (4.5 mg/kg at 0 and 28 days) (24). Although the deaths of two of the sheep can be attributed to trauma, the most likely cause of the remaining deaths in the daily group remains immunosuppression secondary to the stress of daily dosing and inclement weather conditions, exasperated by the potential immunosuppressive effect of oxfendazole.…”

Treatment of mice with fenbendazole attenuates allergic airways inflammation and Th2 cytokine production in a model of asthma

“…6 In direct contrast, others have shown that FBZ treatment of healthy mice attenuates the numbers of splenic CD4 + and CD8 + T cells. 7 In other species, treatment of healthy lambs reduces the ability of circulating lymphocytes to proliferate, particularly during secondary immune responses, 8,9 and FBZ has also been shown to block mitosis of cultured human lymphocytes. 10 These data suggest that FBZ may also affect aspects of mouse immunology.…”

Immunisation of lambs with drug-abbreviated Haemonchus contortus infections: protection against homologous and heterologous challenge

“…The older Romney lambs that were used in our experiment gave a protective response to the abbreviated infections. Another reason for the discrepancy could be the anthelmintic used, as OFZ has some stimulatory ability that could have helped the development of protective immunity in lambs (Stankiewicz et al 1994(Stankiewicz et al , 1996b. The protective response obtained seems primarily to operate at reducing the fecundity of H. contortus.…”