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Bovine colostrum is potentially valuable source of essential fatty acids (FAs), but so far only few studies have made the effort to estimate FA composition of this potential resource. The aim of current research was to fill this gap with selecting and validating an accurate procedure for the analysis of the composition of the FAs in bovine colostrum. We used colostrum samples of Holstein-Friesian cattle from Märja experimental farm as a test material. The validated method includes derivatization, in which FAs are sent through esterification with the acidic catalyst boron trifluoride. Formed methyl esters of fatty acids (FAMEs) were analysed using GC-FID. The obtained LOD and the LOQ of FAMEs were 0.11-0.68 and 0.37-2.27ppm, respectively. The analysis of fortified samples showed very good and similar recoveries, indicating that the method proposed here can be routinely used for determination and investigation of the fatty acids in dairy products.

Nucleation, as well as the processes affecting it, is a constant source of interest for scientists dealing with crystallisation. The majority of published material focuses on secondary nucleation because of the complexity of the crystallisation process. The influence of temperature and different levels of concentration, from highly supersaturated solutions down to lactose solutions below the supersaturated level, on lactose primary cluster was investigated using the dynamic light scattering (DLS) method. The minimum particle size in the solution was found; it varied from 0.89 to 1.17 nm and matched the size of a single lactose molecule (1.18 nm), which was estimated by using molecular modelling techniques. Using the DLS technique, it was confirmed that particle size increased with the decrease of temperature and increasing of concentration of the solution. Theoretical calculations were made to estimate a predicted number of molecules that form particles of primary clusters with different sizes.

Scotta is a by-product from the Ricotta cheese production, which has been studied insufficiently, and that may be the reason of scotta not being widely used for the industrial purpose. The aim of the following research was to study scotta as a raw material for the lactose production and the process of crystallization at different pH levels and concentration factors. In the case, crystallization was carried out at six different pH levels and five concentration factors. The optimum acidity for lactose crystallization was determined close to be at pH 4; at higher or lower pH levels the growth of crystals was inhibited. The relationship between the dimensions of crystals and the concentration factor corresponded to data provided in the literature for the conventional cheese whey. The qualitative properties of the crystals obtained under the examined and recommended conditions were similar to the qualitative properties of crystals reported in the related literature about the cheese whey. It was demonstrated that scotta has a great potential for lactose production, and our results can be used for optimizing the industrial process.

The aim of the present study was to monitor the occurrence of Campylobacter spp. in broiler chicken production in Estonia from 2002 to 2007. Campylobacter spp. was isolated in 163 (12.3%) of 1320 broiler chicken meat samples form 2002 to 2007 and in 115 (6.3%) of 1819 cecal samples in 2005–2007. Campylobacter jejuni was the most commonly isolated species (98.2%), followed by Campylobacter coli (1.4%) and Campylobacter lari (0.4%). The seasonal peak of Campylobacter contamination was from July to September. Our findings showed that Campylobacter contamination at all levels of broiler chicken production in Estonia was low.

The aim of this study was to evaluate the effect of ù-3 PUFA-rich linseed-supplemented diet on the ù-6/ù-3 PUFA content and IGF-I mRNA expression in broiler tissues. Broilers (50 of 21 d old and 90 of 42 d old) were divided into groups according to dietary additives: 1.5% linseed oil (LO), 3.0% LO, 15% linseed cake (LC) and 30% LC and to the duration of modified feeding (1–21, 1–42 and 22–42 days). PUFA content in breast muscles was assayed by gas chromatography and IGF-I mRNA content in liver, muscle and leukocytes was measured by one step RT-PCR. The experimental diets improved the ù-6/ù-3 PUFA ratio through a threefold increase in the ù-3 PUFA content in the breast muscle. The changes in PUFA content were accompanied by changes in IGF-1 gene expression levels in tissues. Therefore, both paracrine and autocrine manner of IGF-1 action are likely to be involved. 15% LC at starting period or 1.5% LO in final diet can be advised as optimal for enriching broiler meat with ù-3 fatty acids.

Most of the acute intestinal diseases are caused by foodborne pathogens with infants and elderly people being at major risk. The aim of this study was to develop a procedure to simultaneously detect 20 foodborne pathogens in complex alimentary matrices such as milk, cheese and meat. The list of targets include, among the others, Listeria spp., Salmonella spp., Shigella spp., Escherichia coli spp., Campylobacter spp., Clostridium spp. and Staphylococcus aureus. The accuracy of detection was determined by using ATCC strains as positive and negative controls. The achieved sensitivity of each of assays was 1 pg of genomic DNA, which was equivalent to ∼1 cfu. The working ranges of the TaqMan(®) Real-time PCR assays, when used quantitatively on cheese and meat samples inoculated with serial dilution of Listeria spp., Listeria monocytogenes, S. aureus, Salmonella enterica, Shigella boydii, E. coli O157:H7, Bacillus cereus, Campylobacter coli, Yersinia enterocolitica, Enterobacter sakazakii and Pseudomonas aeruginosa was 10(8) cfu/g to 10(4) cfu/g. No matrix interferences were observed.

Quail are highly important poultry in regional agricultural poultry meat and egg production (Tikk et al., 2009, 2011). Linseed oil and linseed cake provide components to increase n3- polyunsaturated fatty acid (n3 PUFA) content in poultry products. As described in olive oil and conjugated linoleic acid example, the modification of feed fat composition may result in adverse effects in bird physiological status (Aydin et al. 2001; Karus et al., 2007). Insulinlike growth factors have been well studied and the effect of IGF-1 has been shown to play a significant role in chicken muscle development in all phases (Kocamis and Killefer 2003; Saprokina et al., 2009). The aim of the study was to examine IGF-1 gene-expression and IGF-1 protein content in different feeding conditions in quail blood.

The development of antimicrobial resistance in Campylobacter jejuni and Campylobacter coli is a matter of increasing concern. Because campylobacteriosis is transmitted to humans usually via food of animal origin, the presence of antimicrobial-resistant campylobacters in broiler chickens has important public health implications. The aim of our study was to analyze resistance patterns of C. jejuni isolated from fecal samples collected at a large Estonian chicken farm, from cecal contents collected at slaughterhouses, and from meat samples collected at the retail establishments in 2005 and 2006. A total of 131 C. jejuni isolates were collected over a 13-month period and tested by the broth microdilution VetMIC method (National Veterinary Institute, Uppsala, Sweden) to determine the MICs of various antimicrobials. Resistance to one or more antimicrobials was detected in 104 (79.4%) of the 131 isolates. High proportions of the isolates were resistant to enrofloxacin (73.3%) and nalidixic acid (75.6%). Multidrug resistance (resistance to three or more unrelated antimicrobials) was detected in 36 isolates (27.5%), all of which were resistant to enrofloxacin. Multidrug resistance was significantly associated with enrofloxacin resistance (P < 0.01), and the use of enrofloxacin may select for multiresistant strains.

We studied the dynamics of immune reactions to trekrezan in mouse pups after vaccination of adult mice during pregnancy and mouse pups at different terms after birth with Salmonella typhimurium 34-96. The preparation modulated activity of the immune system and stimulated antibody production in the pre- and postnatal period.