The effects of grain storage containers on aflatoxin production, and the relationship between the level of aflatoxin and the number and weight of fluorescing kernels were determined in corn (Zea maize) stored in controlled climate regimes. Two hundred and forty 100-g samples were held up to 3 mos using four types of storage containers placed in four climates. Storage containers included corn placed in metal cans, paper bags, plastic bags, and paper bags placed in plastic bags. Climates were constant during the duration of the project and included a combination of temperatures and humidities. Temperatures were 29-32 C and 14-18 C; relative humidities were 85-88% and 35-40%. In addition, corn was exposed to environmental conditions conductive for aflatoxin production and 100 g samples were randomly collected, examined under ultraviolet light for fluorescence, and then quantified for aflatoxin levels. Corn samples tested negative for aflatoxin at the beginning of the project. Main (i.e., container, climate, and month) and interactive effects were not observed. Mean levels of aflatoxin ranged from 0 to 151 microg/kg. Aflatoxin was produced regardless of type of storage container, time of storage, and climatic conditions; however, only 8% of the samples produced aflatoxin levels that exceeded 50 microg/kg. Fluorescing corn ranged from 0 to 19 kernels per sample, while aflatoxin levels ranged from 0 to 1,375 microg/kg for the same samples. No relationships were found between the number and weight of fluorescing kernels of corn and aflatoxin levels. The black light test yielded a false negative rate of 23% when in fact the aflatoxin concentrations exceeded 50 microg/kg. Therefore, quantifying fluorescing grain under UV light should not be considered a feasible alternative for aflatoxin testing of grain intended for wildlife.
Experiments on timing the oral treatment of calves for cattle grub control with Trolene at 100 mg./kg. were carried out on ranches near Lethbridge, Alberta, and Kamloops, British Columbia. Groups of 30 and 25 calves, respectively, were treated in November, January, March, and April at Lethbridge and in December, January, February, and March at Kamloops.Control of the pre-hypodermal grubs was equally effective on the first three treatment dates, varying from 94 to 98 per cent mortality. However, variations in the numbers of grubs precluded stating the mortality more precisely than within a range of 95 to 100 per cent at Lethbridge and 89 to 100 at Kamloops.There was no significant difference in mortality between the two species of cattle grubs. However, the third hypodermal instar larvae of both species were less affected by the treatment (P <.01) than those of the preceding instars. Early autumn treatments are recommended to avoid the presence of third-instar larvae and to forestall early damage caused by the hypodermal grubs.Slight symptoms of toxicity, in the form of lethargy and reduced food consumption at Kamloops and ataxia of the hindquarters at Lethbridge, were observed in the calves treated in December and January, respectively. The symptoms disappeared within 48 hours of treatment without the use of antidotes at either locality. The level of treatment used in this study was lower than that reported in the literature to produce first symptoms of toxicity.
ABSTRACTprimarily desi larEe herds. or l#*i-r.rtial.i,fr ii;;.ffi ;1;d'ii"-J.t'.iiii"i"a""got,'tvlor$gcontrolor bid-nc flies, The rieated animals received three applicati_o_ns ot Uo-Kal as e i'i;7-"*'iLr'ri-.i.i,1". *"iili"" ; 3-week
Calves were fed individually for 18 days on a ration of crushed oats treated with Trolene to give a daily dosage of 10 mg./kg. This treatment produced 94 per cent mortality of pre-hypodermal cattle grubs. This was not significantly different from 97 per cent mortality obtained with a single treatment by boluses at 100 mg./kg. The low-level treatment had no effect on the mortality of the pre-hypodermal grubs during the first week of treatment but reached its full effect before the beginning of the third week. Of the hypodermal grubs present at the time of treatment, 94 per cent died and the remainder pupated. The only symptom of toxicity observed was mild diarrhoea in the low-level-treated calves.In a field experiment, two groups of calves that had consumed treated range blocks daily at averages of 7.7 and 4.2 mg. Trolene/kg. for 93 and 64 days showed 95 and 88 per cent mortality, respectively, of the pre-hypodermal grubs. By comparison, another group of calves, treated with boluses at 110 mg. Trolene/kg., showed 80 per cent mortality. The average number of grubs surviving the three treatments were significantly different from each other and from the untreated controls (P <.01). All treatments were begun before hypodermal grubs had appeared. No symptoms of toxicity were seen in the calves of the two low-level-treated groups; ataxia of the hindquarters was observed in the bolus-treated calves on the day following treatment, but these symptoms disappeared on the same day without the use of an antidote.
Aqueous suspensions of 0.25, 0.5, and 0.75 per cent (weight on volume) of CO-RAL in wettable powder were sprayed on Hereford calves for the control of prehypodermic cattle grubs. Two types of CO-RAL sprays were used, one with anionic and the other with a combination of anionic and non-ionic surfactants. They were applied at pressures of 50 and 400 lb. per square inch, and when the lower pressure was used the spray gun was equipped with a hair rake to ruffle the hair. One gal. of spray per head was applied once to the backs and sides of each calf. Sprays containing 0.75 per cent CO-RAL reduced the number of grubs in treated calves by 86 and 90 per cent (P > 0.01) as compared with the number in the untreated group. There was no difference in larvicidal effects between 0.25 and 0.5 per cent sprays, both of which reduced the number of grubs by 60 to 70 per cent. Neither the surfactants used nor the pressures employed had any effect on larvicidal properties of CO-RAL sprays.None of the treated calves showed signs of organophosphorous poisoning, but an outbreak of shipping fever was noticed in the herd. Question is raised if the stress of CO-RAL sprays, which are cholinergic in effect, lowered the resistance of the treated calves to shipping fever, against which they had been vaccinated previously.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.