Animal factors affecting fatty acid composition of cow milk fat: A review

The review summarizes literature dealing with the effects of animal factors (breed, cow individuality, parity and stage of lactation) on fatty acid (FA) composition of milk fat. Genetic parameters affecting the composition of the FAs in milk are reviewed and the possibilities for altering milk fat composition are discussed. Cow individuality and the stage of lactation appear to be the main animal factors affecting milk fat composition. Breed and parity affect the variability in FA composition to a limited extent. Some of these factors can be used effectively to alter milk fat composition. Polymorphism of the enzymes, stearoyl-CoA desaturase (SCD) and acyl-CoA-diacylglycerol acyltransferase (DGAT) can explain to some extent the variability among cows. The great individual differences, probably given by varying SCD activities, may be used in breeding programmes, supported by the heritability estimates determined for individual FAs. Effective results can also be achieved through the combined effect of several factors. For instance, the level of conjugated linoleic acid could be increased not only by feed factors, but also through thorough knowledge of rumen biohydrogenation or by cow selection using information on SCD and DGAT polymorphism. The animal factors that are discussed are closely related to milk yield, particularly fat content. Both parameters can change FA composition. Thus, it is necessary in breeding programmes to take these relationships into consideration, along with known genetic correlations.Keywords: Breed, genetic correlations, heritability, milk and fat yield, parity, single nucleotide polymorphism, stage of lactatio

The effect of cattle breed, season and type of diet on the fatty acid profile of raw milk

The aim of the study was to determine the effect of cow breed, season and type of diet on the fatty acid (FA) profile of raw milk. A 2-year study was conducted on bulk milk samples collected from eight herds consisting of Czech Fleckvieh (CF, four herds) and Holstein (H, four herds) breeds. One half of the herds of each breed was grazed (G), while the other half was not (N). Samples were collected twice in winter (W) and twice in summer (S). Milk yield in CF (5385.50 kg) was lower than in H (7015.15 kg, <i>P</i> &lt;  0.05). The effect of breed was found in odd-chain, branch-chain and hypercholesterolemic FAs (<i>P</i> &lt;  0.05). The content of fat was lower in summer (S) than in winter (W), being 3.71 and 3.91 g 100 g⁻¹, respectively (<i>P</i> &lt;  0.05). The proportion of saturated and polyunsaturated FAs was lower in S than in W (<i>P</i> &lt;  0.05). The content of monounsaturated FAs was higher in S (30.69 g 100 g⁻¹) than in W (27.72 g 100 g⁻¹, <i>P</i> &lt;  0.05). Milk yield in grazing herds (G, 5197.50 kg) was lower (<i>P</i> &lt;  0.05) than in non-grazing herds (N, 7203.75 kg). The sum of saturated and hypercholesterolemic FAs was lower and the sum of monounsaturated and odd-chain FAs was higher in G than in N (<i>P</i> &lt;  0.05). Content of conjugated linoleic acid (CLA) and C18:3n3 was higher in G (0.93 and 0.64 g 100 g⁻¹) than in N (0.42 and 0.39 g 100 g⁻¹, respectively, <i>P</i> &lt;  0.001)

Carlina acaulis and Trachyspermum ammi essential oils formulated in protein baits are highly toxic and reduce aggressiveness in the medfly, Ceratitis capitata

Essential oil (EO)-based botanical insecticides are considered a promising option for Integrated Pest Management (IPM). However, the sublethal effects of EO-based insecticides are understudied. No information is available on the potential effects of EO exposure on insect aggressive traits. In this study, the toxicity of two EOs with documented efficacy on insect vectors and agricultural pests, and which were obtained from the roots of silver thistle (Carlina acaulis L., Asteraceae) and seeds (i.e. schizocarps) of ajwain (Trachyspermum ammi (L.) Sprague, Apiaceae), was evaluated against adults of the Mediterranean fruit fly, Ceratitis capitata (Wiedemann) (medfly), a cosmopolitan frugivorous pest. Both EOs were formulated in a mucilaginous solution containing sucrose and hydrolyzed proteins, suitable for "attract and kill" tests. After testing the EO ingestion toxicity on medflies, lethal concentrations LC10, and LC30 were calculated. Behavioral tests were carried out to assess the effect of EO feeding on the medfly aggressive traits. Both EOs formulated in protein baits showed promising insecticidal activity on medflies. Lethal concentrations 50 (LC50) of C. acaulis and T. ammi EOs were 1094 ppm and 3963 ppm, respectively. Medflies fed on protein baits treated with EO LC10 and LC30 showed a significant reduction in the overall abundance of aggressive interactions at the population level, as well as shorter aggression duration over control flies. Concerning aggression scores, no differences were found between treated and control flies. This study underlines the promising potential of C. acaulis and T. ammi EOs for the development of eco-friendly formulations to be used in medfly “attract and kill” approaches. It also outlined how exploiting food sources contaminated by low EO concentrations can strongly impact medfly aggressiveness, which is of key importance for the successful reproduction of this important fruit pest

Endogenous and food-derived polyamines: determination by electrochemical sensing

olyamines (PAs) are involved in a variety of fundamental physio-pathologic processes. The concentration of these polycations in organs and tissues depends on their endogenous production and oxidation rates, and on their intake from foods. Besides being largely accepted as markers for the progress of several pathologies, PAs may exert themselves different effects on humans, ranging from being positive to be drastically detrimental depending on the organism conditions. Thus, if the determination of polyamines content in tissue samples is of great importance as they could be indicators of several diseases, their quantification in food is fundamental for modulating the diet to respond to a specific human health status. Thus, the determination of PA content in food is increasingly urgent. Standard analytical methods for polyamine quantification are mainly based on chromatography, where high-performance liquid chromatography and gas chromatography are the most often used, involving pre-column or post-column derivatization techniques. Driven by the growing need for rapid in situ analyses, electrochemical biosensors, comprising various combinations of different enzymes or nanomaterials for the selective bio-recognition and detection, are emerging as competitors of standard detection systems. The present review is aimed at providing an up-to-date overview on the recent progresses in the development of sensors and biosensors for the detection of polyamines in human tissues and food samples. Basic principles of different electrochemical (bio)sensor formats are reported and the applications in human tissues and in foods was evidenced