The use of genetic engineering techniques to improve the lipid composition in meat, milk and fish products: a review

Cows as Bioreactors for the Production of Nutritionally and Biomedically Significant Proteins

Dairy and beef cattle make a vital contribution to global nutrition, and since their domestication, they have been continuously exposed to natural and artificial selection to improve production characteristics. The technologies of transgenesis and gene editing used in cattle are responsible for generating news characteristics in bovine breeding, such as alteration of nutritional components of milk and meat enhancing human health benefits, disease resistance decreasing production costs and offering safe products for human food, as well as the recombinant protein production of biomedical significance. Different methodologies have been used to generate transgenic cattle as bioreactors. These methods include the microinjection of vectors in pronuclear, oocyte or zygote, sperm-mediate transgenesis, and somatic cell nuclear transfer. Gene editing has been applied to eliminate unwanted genes related to human and animal health, such as allergy, infection, or disease, and to insert transgenes into specific sites in the host genome. Methodologies for the generation of genetically modified cattle are laborious and not very efficient. However, in the last 30 years, transgenic animals were produced using many biotechnological tools. The result of these modifications includes (1) the change of nutritional components, including proteins, amino acids and lipids for human nutrition; (2) the removal allergic proteins milk; (3) the production of cows resistant to disease; or (4) the production of essential proteins used in biomedicine (biomedical proteins) in milk and blood plasma. The genetic modification of cattle is a powerful tool for biotechnology. It allows for the generation of new or modified products and functionality that are not currently available in this species.

Milk production related to price of raw cow’s milk in selected european countries

Dairy industry and its production contributes to the economies of many regions and countries worldwide. Except the milk production there is also number of other impacts such as the human nutrition, landscape creation and environment among the others. The European dairy sector undergoes numerous changes a period of crises and regulations in last few decades. After abolition of milk quota system, the European milk producing countries started to be exposed to the milk prices of the world market. In the submitted article, the impact of five explanatory variables, which cow's milk, butter, milk powder, cheese, and farm milk production belong among, is analysed to the explained variable the price of raw cow's milk coming from the countries whose data is available in the Eurostat database; that is, Austria, Belgium, Croatia, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, and the United Kingdom. Regression analysis of panel data with territorial and time dimensions is applied using three techniques, which the pooling, the random, and the between approach belong to. Supplementary analytical approach represented by the cluster analysis resulted into triplet of clusters, selected for the further modelling process. Results of the regression analysis showed no influence of butter production to the level of raw cow's milk. The visualised outcome signifies the distribution of the individual countries among the examined clusters. It underlines the fact that the cheaper raw cow's milk price causes a concentration on the specific part of the production that is easier to produce. It is important to realise that the coefficient of determination of the regression models reveal their statistical significance as a whole. Obtained results can serve as the background for further analysis of impact of other milk products as the factors influencing the raw cow's milk prices.

Simultaneous determination of eugenol, isoeugenol and methyleugenol in fish fillet using gas chromatography coupled to tandem mass spectrometry

Gas chromatography (GC) coupled with triple quadrupole tandem mass spectrometry (MS/MS) operated in electron ionization mode (EI) has been shown to have advantages in the trace analysis of chemical compounds. Employing the instrument, a method has been built to simultaneously determine eugenol, isoeugenol' and methyleugenol, which have been widely used as fish anesthetic, in the fish fillet. Procedure for the sample preparation was achieved by using hexane extraction followed by phenyl solid phase extraction (SPE) cleanup, which was free of such steps as rotary evaporation and nitrogen blowing by taking the volatility of eugenol and its isomers into consideration. The method was validated by conducting recovery studies on fortified fish fillet samples at four concentrations. The linearity in the range of 5-500μg·L(-1) was forced through the origin giving a coefficient of determination (r(2)) greater than 0.9982. Limits of detection (LODs) for eugenol, isoeugenol' and methyleugenol were 0.4, 1.2' and 0.2μg·kg(-1), respectively. The limits of quantification (LOQs) were 1.2, 4' and 0.7μg·kg(-1) for eugenol, isoeugenol' and methyleugenol, respectively. The recoveries for eugenol and its isomers ranged from 76.4 to 99.9% with relative standard deviations (RSD) in a range from 2.18 to 15.5%. This method is quick, simple and suitable for determining the residues of eugenol, isoeugenol and methyleugenol simultaneously in batch samples of fish fillet.