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1.
The horse milk gains increasing interest as a food product for sensitive consumers, such as children with food allergies or elderly people. We investigated the plasma and milk disposition, faecal excretion and efficacy of per os ivermectin (IVM) and pour‐on eprinomectin (EPM) in horses. Ten mares were divided into two groups. The equine paste formulation of IVM and bovine pour‐on formulation of EPM were administered orally and topically at dosage of 0.2 and 0.5 mg/kg bodyweight. Blood, milk and faecal samples were analysed using high‐performance liquid chromatography. The plasma concentration and persistence of IVM were significantly greater and longer compared with those of EPM. Surprisingly, EPM displayed a much higher disposition rate into milk (AUCmilk/plasma: 0.48) than IVM (AUCmilk/plasma: 0.19). IVM exhibited significantly higher faecal excretion (AUCfaeces: 7148.54 ng·d/g) but shorter faecal persistence (MRTfaeces: 1.17 days) compared with EPM (AUCfaeces: 42.43 ng·d/g and MRTfaeces: 3.29 days). Faecal strongyle egg counts (EPG) were performed before and at weekly intervals after treatment. IVM reduced the EPG by 96–100% for up to 8 weeks, whereas the reduction in the EPM group varied from 78 to 99%. In conclusion, due to the relatively low excretion in milk, EPM and IVM may be used safely in lactating mares if their milk is used for human consumption. Nevertheless, much lower plasma and faecal availabilities of EPM could result in subtherapeutic concentrations, which may increase the risk of drug resistance in nematodes after pour‐on EPM administration compared with per os IVM.  相似文献   
2.
The development, fecundity and survival ofStethorus gilvifrons Mulsant (Coleoptera: Coccinellidae) fed onTetranychus cinnabarinus Boisduval (Acari: Tetranychidae) were recorded at three constant temperatures (20, 25 and 30±1°C) and 50±10% relative humidity, under two photoperiods (16:8 L:D and 8:16 L:D) produced using artificial light (4000 lux). The development rate for the egg stage (r[Te]) increased linearly with increasing temperature (r[Te]=0.0132*T ? 0.0955; R2=0.95). The theoretical egg-development threshold was estimated to be 7.24°C; 75.75 degree-days (DD) were required for hatching. The total development time (r[Tt]) also decreased linearly with increasing temperature (r[Tt]=0.0039*T ? 0.0325; R2=0.98). The development threshold was estimated to be 8.33°C and full development from egg to adult required 256.41 DD. Higher temperatures resulted in a shorter generation time (T 0) and decreased net reproductive rate (R 0). The length of the previposition and postoviposition period, as well as longevity, decreased significantly with increasing temperature under both photoperiods. The oviposition and postoviposition periods, longevity, and total fecundity were not significantly affected by photoperiod. The values of both the intrinsic rate of increase (r m ) andR 0 were highest under the long-day photoperiod at 25°C. The mortality rate was lowest at 20°C under the short-day photoperiod. Of the conditions tested, the optimum temperature for rearingS. gilvifrons was 25°C and the optimum photoperiod was 16:8 L:D.  相似文献   
3.
The aim of this study was to test the applicability of electrical stimulation of lumbar spinal nerve roots and obtain normative electrical root stimulation (ERS) data for L7 nerve root and sciatic nerve in dogs. For that purpose ERS and sciatic nerve stimulations were performed consecutively, in totally 40 healthy dogs. ERS was applied in the L7/S1 intervertebral space via monopolar needle electrodes. Muscle responses were recorded from the gastrocnemius muscles on the left and right hind limbs. Sciatic nerve stimulation was performed at the greater trochanter level on the left hind limb, with records obtained from the left gastrocnemius muscle. Mean root latencies of the left and right side were 5.22?±?0.49 ms and 5.29?±?0.53 ms, respectively. There was no significant difference in root latency between the right and left sides. The mean terminal latency was 3.82?±?0.46 ms. The proximal motor nerve conduction velocity of the sciatic nerve was 63.15?±?3.43 m/s. The results of this study show that ERS provides objective data about the integrity of lumbar spinal nerve roots by evaluating the entire population of motor fibres and total length of the motor axon in dogs. ERS can be considered a useful diagnostic method for confirmation of diagnoses of lumbosacral diseases.  相似文献   
4.
Since there is no registered anthelmintic drug available for use in goats, extra-label use of drugs is a common practice in most countries. The aim of the present study was to compare the pharmacokinetic disposition of levamisole (LVM)-oxyclozanide (OXZ) combination in sheep and goats following per os administration. Goats (n = 8) and sheep (n = 8) 12- to 16-months-old were used for this study. The animals received tablet formulation of LVM and OXZ combination orally at a dose of 7.5 mg/kg and 15 mg/kg body weight, respectively. Blood samples were collected by jugular vein at different times between 5 min and 120 h after drug administrations. The plasma concentrations of LVM and OXZ were analyzed by HPLC following liquid-liquid phase extraction procedures. The plasma concentrations and systemic availabilities of both LVM and OXZ in goats were lower and the plasma persistence of LVM was shorter compared with those observed in sheep. Terminal half-lives (t1/2λz) of both molecules are shorter in goats compared with those in sheep. Goats treated with LVM-OXZ combination at the recommended dose for sheep may result in a reduced efficacy, because of under-dosing, which may increase the risk of drug resistance in parasites. Increased or repeated dose could be a strategy to provide higher plasma concentration and thus to improve the efficacy against the target parasites in goats compared with sheep. However, some adverse reactions may occur since LVM has relatively very narrow therapeutic index due to its nicotine-like structure and effect.  相似文献   
5.
Functional properties of conventional oat materials are relatively poor with respect to foam and emulsion formation and stabilization. This is largely due to the poor solubility of oat proteins and the presence of lipids in aqueous extracts of oats. In the experimental part of this study, extracts were prepared from different type oat flours (oat endosperm flour, oat fine flour, CO2-defatted whole oat flour and CO2-defatted oat flour) with a buffered aqueous extraction procedure at acidic (pH 4.5 and 6.5) and basic (pH 8.5 and 10.5) regions. The solubility of proteins was the highest at pH 10.5 and NaCl concentration of 2%. Among the extracts, CO2-oat flour showed improved foaming and emulsifying properties at basic pH values. The presence of 0.1% NaCl resulted in the lowest foam volumes, but the emulsion activity and stability values being the highest. Sucrose addition resulted in increased foam and emulsion stability of suspensions. Heat treatment at 80 °C impaired foam properties, whereas the stability of emulsions increased with the increase in temperature from 20 °C to 80 °C. CO2-extracted oats can be useful raw materials in beverages and other aqueous applications where protein functionality plays an important role.  相似文献   
6.
Aflatoxins spiked at three different levels (6.5, 13.0, and 19.5 microg/kg) in tahini, a sesame butter, were analyzed by using three different methods: high-performance liquid chromatography (HPLC), fluorometry, and enzyme-linked immunosorbent assay (ELISA). An immunoaffinity column was used for cleanup and purification of extracts prior to detection by HPLC and fluorometry. All methods were statistically evaluated for accuracy, precision, and simple correlations. Additionally, 14 tahini samples randomly obtained from Turkish retail markets were analyzed using an immunoaffinity column cleanup procedure coupled with the HPLC detection method. The fluorometric determination method involving an immunoaffinity column cleanup step was found to be highly correlated with the HPLC method (r = 0.978). Both methods were found to be effective due to their high recoveries and low variance for the prediction of total aflatoxin contamination in tahini samples. The ELISA method, due to its high variation in replicates, was found to be applicable only as a screening method. The survey study demonstrated the need for control of aflatoxin contamination of foodstuffs involving sesame seeds as an ingredient.  相似文献   
7.
8.
Human milk fat (HMF) analogue containing docosahexaenoic acid (DHA) and arachidonic acid (ARA) at sn-1,3 positions and palmitic acid (PA) at sn-2 position was produced. Novozym 435 lipase was used to produce palmitic acid-enriched hazelnut oil (EHO). EHO was then used to produce the final structured lipid (SL) through interesterification reactions using Lipozyme RM IM. Reaction variables for 3 h reactions were temperature, substrate mole ratio, and ARASCO/DHASCO (A:D) ratio. After statistical analysis of DHA, ARA, total PA, and PA content at sn-2 position, a large-scale production was performed at 60 °C, 3:2 A:D ratio, and 1:0.1 substrate mole ratio. For the SL, those results were determined as 57.3 ± 0.4%, 2.7 ± 0.0%, 2.4 ± 0.1%, and 66.1 ± 2.2%, respectively. Tocopherol contents were 84, 19, 85, and 23 μg/g oil for α-, β-, γ-, and δ-tocopherol. Melting range of SL was narrower than that of EHO. Oxidative stability index (OSI) value of SL (0.80 h) was similar to that of EHO (0.88 h). This SL can be used in infant formulas to provide the benefits of ARA and DHA.  相似文献   
9.
Brans of specialty sorghum varieties (high tannin, black, and black with tannin) were used to investigate the effects of sorghum phenolic compounds on starch digestibility of soft and hard sorghum endosperm porridges. Endosperms of varieties with the highest and lowest grain hardness index were mixed with brans of specialty sorghum varieties in the ratio of 85:15 and cooked into porridges with distilled water using a Rapid Visco Analyzer. Brans of condensed tannin containing sorghum varieties (high‐tannin and black with tannin sorghums) significantly (P < 0.05) decreased starch digestibility and estimated glycemic index (EGI) and increased resistant starch (RS) content of endosperm porridges. However, the addition of phenolic‐rich tannin‐free (mostly anthocyanins) black sorghum bran significantly (P < 0.05) increased starch digestibility and EGI but did not affect RS content of endosperm porridges. The disparate effects with black bran may, in part, result from its larger particle size and different bran structure compared with other sorghum varieties evaluated. Thus, our study showed that not only presence of phenolic compounds in the brans but also structural differences of specialty sorghum brans can have significant effects on starch digestibility.  相似文献   
10.
AIMS: To determine the plasma disposition and concentrations of ivermectin (IVM) in eggs produced by laying hens following S/C, oral and I/V administration.

METHODS: Twenty-four laying hens, aged 37 weeks and weighing 1.73 (SD 0.12) kg were allocated to three groups of eight birds. The injectable formulation of IVM was administered either orally, S/C, or I/V, at a dose of 0.2?mg/kg liveweight, following dilution (1:5, v/v) with propylene glycol. Heparinised blood samples were collected at various times between 0.25 hours and 20 days after drug administration. Eggs produced by hens were also collected daily throughout the study period. Samples of plasma and homogenised egg were analysed using HPLC.

RESULTS: Maximum concentrations of IVM in plasma and mean residence time of IVM were lower after oral (10.2 (SD 7.2) ng/mL and 0.38 (SD 0.14) days, respectively) than after S/C (82.9 (SD 12.4) ng/mL and 1.05 (SD 0.24) days, respectively) administration (p<0.01). The time to maximum concentration and elimination half-life were shorter following oral (0.14 (SD 0.04) and 0.23 (SD 0.11) days, respectively) than S/C (0.25 (SD 0.00) and 1.45 (SD 0.45) days, respectively) administration (p<0.01). IVM was first detected in eggs 2 days after treatment in all groups and was detected until 8 days after oral and I/V administration, and until 15 days after S/C administration. Peak concentrations of IVM were 15.7, 23.3 and 1.9?µg/kg, observed 2, 5 and 4 days after I/V, S/C and oral administration, respectively.

CONCLUSIONS AND CLINICAL RELEVANCE: The low plasma bioavailability of IVM observed after oral administration in laying hens could result in lower efficacy or subtherapeutic plasma concentrations, which may promote the development of parasitic drug resistance. Due to high IVM residues in eggs compared to the maximum residue limits for other food-producing animal species, a withdrawal period should be necessary for eggs after IVM treatment in laying hens.  相似文献   
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