Efficacy of beer fermentation residue containing Saccharomyces cerevisiae cells for ameliorating aflatoxicosis in broilers.

This study aimed to determine the aflatoxin B1 (AFB1) binding capacity of a beer fermentation residue (BFR) containing Saccharomyces cerevisiae cells, and the efficacy of BFR to ameliorate the toxic effects of AFB1 on performance, serum biochemistry, and histology of broilers. The BFR was collected from a microbrewery, and the yeast cells were counted, dried, and milled before it was used in the study. In vitro evaluation of the BFR was conducted using different concentrations of AFB1 (2.0, 4.0, 8.0, 16.0, and 32.0 µg AFB1/mL) and 100 mg/10 mL of BFR at pH 3.0 or 6.0. Two hundred 1-day-old male broilers (Ross 308) were assigned to chick batteries and allowed ad libitum access to feed and water. A completely randomized design was used with 5 replicate pens of 5 chicks assigned to each of 4 dietary treatments from hatch to 21 d, which included: 1) basal diet (BD), with no BFR or AFB1; 2) BD supplemented with 1% BFR; 3) BD supplemented with 2 mg AFB1/kg of feed; and 4) BD supplemented with 2 mg AFB1/kg feed and 1% BFR. Performance variables were determined weekly, while serum analyses were performed on d 14 and 21. At the end of the study, chicks were anesthetized with carbon dioxide, euthanized by cervical dislocation, and the kidney, liver, and bursa of Fabricius were removed for determination of relative weights, and for histological evaluation. In vitro assays showed that the higher the initial AFB1 concentration in solution, the greater the AFB1 amount adsorbed by BFR at both pHs tested. Feed intake, BW gain, and concentrations of albumin, total protein, and globulin increased (P < 0.05) in broilers fed BFR+AFB1 (Diet 4), when compared to the birds receiving only AFB1 (Diet 2). Although BFR was not able to reduce or prevent the effects of AFB1 on relative weights of kidneys and liver, it reduced the severity of histological changes in the liver and kidney caused by AFB1.

The Plasmodium falciparum chloroquine in vivo test: extended follow-up is more important than parasite counting.

349 in vivo tests of the susceptibility of Plasmodium falciparum to chloroquine, 25 mg/kg, were analysed. In some surveys, standard in vitro tests were also carried out. The proportions of sensitive and resistant infections in different areas found by the 2 methods were similar, but, within a given area, correlation between the two methods was often poor. Two RI cases and one RII/RIII case were sensitive in vitro, and it is suggested that the extended in vivo test may sometimes be more sensitive than the in vitro test, and that even in endemic areas, where reinfection is possible, patency on day 14 will nearly always be due to resistance. Parasite density data were analysed by calculating the geometric mean of each day's parasite density as a percentage of the day 0 parasite density + 0.1. Most resistant and sensitive infections attained minimal values on day 4, and it is proposed that assessment of sensitivity based on parasite densities should use day 4 values. Contrasts between materials were more clearly defined statistically when comparisons were based on ranking in vivo test classifications, than when based on day 4 parasitaemia. It is therefore suggested that, for epidemiological purposes, extension of tests to at least 14 d is more important than parasite counting. Parasitaemia above 20-25% of the day 0 value on day 2 in a severely ill patient, or persistent patency on day 4 in a symptomatic patient, are both indications for a change of treatment.