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Detection of twelve mycotoxins in mixed animal feedstuffs, using a novel membrane cleanup procedure.
B A Roberts D S Patterson 《Journal of the Association of Official Analytical Chemists》1975,58(6):1178-1181
A multimycotoxin thin layer chromatographic screening method is described which is applicable to most animal feedstuffs. Interference from nonspecific lipid, pigment, and other components of simple and mixed feeds is reduced to a minimum by using a membrane cleanup step. Aflatoxins B1, B2, G1, and G2, citrinin, diacetoxyscirpenol, ochratoxin A, patulin, penitrem A, sterigmatocystin, T-2 toxin, and zearalenone may be reliably detected. The sensitivity of the method is generally low for mixed feeds but even so aflatoxin B1 can be detected at a level of 3 ppb and ochratoxin A at 80 ppb. While the basic method is less sensitive for sterigmatocystin (330 ppb), patulin (600 ppb), zearalenone (1000 ppb), and the trichothecenes (1000-4000 ppb), it may be adapted so as to reduce the above detection limits when the presence of these toxins is suspected. Lower levels may be detected in extracts of simple feeds. 相似文献
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Abstract – The persistent effects of embryonic temperature stress and individual parentage on fry swimming performance were examined in a cross‐fertilisation experiment using sockeye salmon (Oncorhynchus nerka). A fixed‐velocity test of burst swimming was used to assess the endurance capacity and behavioural performance of individual fry from 10 offspring families incubated at 12, 14 or 16 °C to hatch and then reared through yolk absorption and exogenous feeding stages in a common posthatch environment (average 6.9 °C). Fry burst swim time (BST) was influenced by an interaction between incubation temperature and family identity. Average BST was longer for fry from the 12 °C prehatch treatment compared to 14 and 16 °C, although differences were largely attributable to temperature effects on average fry size. Behavioural observations revealed that fish incubated at 16 °C performed more poorly, having a larger proportion of individuals that required stimulation to swim, fatigued more frequently or were classified as ‘nonswimmers’. Within all three incubation temperature treatments, mean BST varied significantly among offspring families, independent of fry mass and length. An interesting relationship was observed within the 16 °C treatment, whereby families with higher survivorship were characterised with lower mean BSTs. Collectively, these findings demonstrate that exposure to high temperatures in early sockeye salmon development can result in persistent, parentally mediated effects on fry performance. As such, these results provide important insight into how elevated temperature events during egg incubation may affect early life history selection processes and survival in stages beyond when the stressor is experienced. 相似文献
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Strauch TA Scholljegerdes EJ Patterson DJ Smith MF Lucy MC Lamberson WR Williams JE 《Journal of animal science》2001,79(3):574-581
The objectives of this study were to evaluate the effects of pre- and postpartum undegraded intake protein (UIP) supplementation on body condition score (BCS), BW, calf weight, milk production, serum IGF-I concentrations, and postpartum interval in primiparous beef heifers (n = 44). Heifers were maintained on endophyte-free stockpiled tall fescue (11.7% CP, 38% ADF) and individually fed supplement daily beginning 60 d prepartum. Pre- and postpartum supplements provided 19.3% CP, 83.4% TDN (UIP); 14.1% CP, 84.1% TDN (Control); 21.5% CP, 81.5% TDN (UIP); and 14.6% CP, 81.4% TDN (Control); respectively. Blood meal (146 g/d) was the source of UIP. Six heifers were removed from the study due to calf loss unrelated to treatment; therefore, postpartum measurements are based on 19 animals per treatment. Statistical analyses using ANOVA and a split-plot design revealed no effects of treatment (P > 0.2) on BCS, BW, calf weight, milk production, or postpartum interval. There tended to be a treatment x time interaction on BCS (P < 0.09) with UIP heifers having higher BCS than Control at wk 5, 7, and 9 postpartum. There was a treatment x time interaction on serum IGF-I (P < 0.06) during the first 35 d postpartum. In UIP heifers, serum IGF-I was greater at calving compared with Control heifers (117.5 vs 92.4 ng/mL, respectively); however, these differences were not related to changes in BCS or BW. Although serum IGF-I concentrations were increased at calving in heifers receiving UIP, there were no treatment effects on postpartum interval (P > 0.7). During the first 30 d postpartum, IGF-I differed (P < 0.01) among heifers with postpartum intervals defined as short, < 50 d (128.9 ng/mL); medium, 51 to 65 d (115.2 ng/mL); and long, 66 to 130 d (52.9 ng/mL). When analyzed as a regression, a 1 ng/mL increase in IGF-I (UIP and Control heifers) at calving (P < 0.05) and throughout the postpartum period (P < 0.01) corresponded to a decrease in postpartum interval of 0.13 d. Based on the results of this study, the inclusion of UIP in diets for primiparous heifers and its effects on postpartum interval warrant further evaluation. 相似文献
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L J Patterson K K Shappell M B Hurtig 《Journal of the American Veterinary Medical Association》1989,195(1):101-102
Mandibular condylectomy was effective in improving mastication and stopping weight loss in a horse. The horse had a history of intermittent purulent drainage from a facial wound and unilateral ankylosis of the temporomandibular joint. 相似文献
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Four species of adult Diptera, Rhagoletis pomonella (Walsh), Drosophila melanogaster Mg., Drosophila hydei Sturt., and Musca domestica L. showed varying degrees of reduced fecundity when sublethal doses of arsenic were included in their food. The possible influence of the frequent use of arsenicals on arthropod populations is discussed. 相似文献
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