ABSTRACT
A method for the simultaneous determination of three commonly used coccidiostats in chicken liver was developed, comprising a multi-residue QuEChERS (quick, easy, cheap, effective, rugged and safe) extraction step, and a liquid chromatography-ultra violet-fluorescence (HPLC-UV/FL) analysis. The QuEChERS extraction was optimized using an experimental design approach that includes a screening step to obtain the critical variables, an optimization step using multiple response surface analysis and the calculation of a desirability parameter. The optimized method was validated with fortified samples, reaching an average recovery of 91% and an overall precision of 5.5% (mean of three analytes at three levels). Limits of detection calculated on fortified samples were 20 µg kg-1 for lasalocid, 15 µg kg-1 for nicarbazin and 120 µg kg-1 for diclazuril. These values resulted at least one order of magnitude lower than the maximum allowed residue limit (MRL) of the studied coccidiostats for chicken liver.
Subject(s)
Chickens , Coccidiostats/analysis , Lasalocid/analysis , Nicarbazin/analysis , Nitriles/analysis , Triazines/analysis , Animals , Chromatography, High Pressure Liquid/methods , Coccidiostats/isolation & purification , Feasibility Studies , Food Safety , Lasalocid/isolation & purification , Liquid-Liquid Extraction , Liver/chemistry , Nicarbazin/isolation & purification , Nitriles/isolation & purification , Poultry , Research Design , Time Factors , Triazines/isolation & purificationABSTRACT
Here we evaluate the effects of BpLec, a C-type lectin isolated from Bothrops pauloensis snake venom, on Toxoplasma gondii parasitism. BpLec (0.195-12.5 µg/mL) did not interfere with HeLa (host cell) viability by MTT assay, whereas higher doses decreased viability and changed HeLa morphology. In addition, the host cell treatment before infection did not influence adhesion and proliferation indexes. BpLec did not alter T. gondii tachyzoite viability, as carried out by trypan blue exclusion, but decreased both adhesion and parasite replication, when tachyzoites were treated before infection. Galactose (0.4 M) inhibited the BpLec effect on adhesion assays, suggesting that BpLec probably recognize some glycoconjugate from T. gondii membrane. Additionally, we performed cytokine measurements from supernatants collected from HeLa cells infected with T. gondii tachyzoites previously treated with RPMI or BpLec. MIF and IL-6 productions by HeLa cells were increased by BpLec treatment. Also, TGF-ß1 secretion was diminished post-infection, although this effect was not dependent on BpLec treatment. Taken together, our results show that BpLec is capable of reducing T. gondii parasitism after tachyzoite treatment and may represent an interesting tool in the search for parasite antigens involved in these processes.
Subject(s)
Bothrops/metabolism , Coccidiostats/chemistry , Coccidiostats/pharmacology , Lectins, C-Type/chemistry , Toxoplasma/drug effects , Venoms/chemistry , Animals , Cell Line , Cell Survival/drug effects , Coccidiostats/isolation & purification , Cytokines/metabolism , HeLa Cells , Humans , Lectins, C-Type/isolation & purificationABSTRACT
The classical and the most commonly used approach for the prevention of coccidiosis in chickens is the incorporation of synthetic coccidiostats into their feed during the first weeks of their life. This approach has been challenged by consumers, objecting against residual antimicrobials and drug resistant microorganisms that may contaminate poultry products. Moreover, the coccidiostat application approach has been challenged in the last decade by the emerging regulations in the developed world, targeting the cessation of such a practice. The pressures from the consumers as well as from regulation agencies resulted in a great need for alternative methods to reduce, or completely replace the use of coccidiostats in modern chicken production. This replacement requires seeking for safer products that do not have any negative impact on the consumer's health. Such products are very much in demand, especially in organic poultry farming. The purpose of this review is to present approaches for the replacement of coccidiostat application in chickens through improvements in poultry house management, research in vaccine developments, and application of holistic natural products for the prevention of the economic losses resulting from coccidiosis.(AU)
Subject(s)
Animals , Birds/growth & development , Coccidiostats/analysis , Coccidiostats/isolation & purificationABSTRACT
The classical and the most commonly used approach for the prevention of coccidiosis in chickens is the incorporation of synthetic coccidiostats into their feed during the first weeks of their life. This approach has been challenged by consumers, objecting against residual antimicrobials and drug resistant microorganisms that may contaminate poultry products. Moreover, the coccidiostat application approach has been challenged in the last decade by the emerging regulations in the developed world, targeting the cessation of such a practice. The pressures from the consumers as well as from regulation agencies resulted in a great need for alternative methods to reduce, or completely replace the use of coccidiostats in modern chicken production. This replacement requires seeking for safer products that do not have any negative impact on the consumer's health. Such products are very much in demand, especially in organic poultry farming. The purpose of this review is to present approaches for the replacement of coccidiostat application in chickens through improvements in poultry house management, research in vaccine developments, and application of holistic natural products for the prevention of the economic losses resulting from coccidiosis.