The aim of this paper was to compare the microbiological and sensory quality of Polish and Thailand multifloral honeys. The honeys selected for testing were classified into the multifloral honey group on the basis of a pollen analysis. The microbiological analyses of multifloral honey samples confirmed a good microbiological quality of the honey samples tested. No presence of pathogenic bacteria of the species Salmonella has been demonstrated. The total number of aerobic mesophilic microorganisms and the number of mesophilic bacteria of the species Bacillus were less than the permissible microbiological limits for bee products. A significant excess of yeasts and moulds was found in one Thailand honey sample, which produced undesirable sensory factors as a result of honey fermentation. The tests performed revealed that lime and multifloral honeys were the varieties most preferred by consumers and that most consumers presented a neutral attitude towards imported honeys. A consumer sensory test showed differences in the quality of the honey samples tested. Three samples of domestic multifloral honeys and one sample of imported honey were assessed as the most attractive. Two Thailand honey samples were characterized by a significantly lower sensory quality than the other samples tested in the study. The method of sensory profiling applied in this study made it possible to be obtained precise information on the reasons for consumers’ preferences identified during the hedonic test. The results for the most unattractive samples obtained by this method were confirmed by the results of microbiological and physicochemical analyses.

The aim of the study was to determine the relationship between the quality of colostrum and the formation of intestinal bacterial microflora in calves from birth to day 7. Seventy-five multiparous Polish Holstein–Friesian cows were selected. Colostrum samples were collected individually up to two hours after calving. The analysis was carried out on 75 calves; which were divided into three groups based on the colostrum quality class of the first milking. Faecal samples were collected rectally from each calf on its seventh day of life. Calves were weighed twice; on days 0 and 7 of life. It has been shown that with a higher concentration of colostrum protein fraction, primarily immunoglobulins, the colonisation of anaerobic bacteria occurs faster. Colostrum with a density >1.070 g/cm3 promoted the significant development of Lactobacilli and Bifidobacterium spp. which at the same time contributed to the reduction of unfavourable microflora, such as Coliforms or Enterococci. Regardless of the initial body weight, daily weight gains were highest for calves fed with colostrum with a density >1.070 g/cm3. The study showed a significant influence of colostrum quality class on the formation of the intestinal microflora and the daily weight gains of calves.

The aim of the study was to determine the effect of linseed cake supplementation during the winter period as a factor influencing the level of some bioactive components (milk composition, fatty-acid profile, and fat-soluble vitamins) in the milk fat fraction in cows kept on an organic farm. Forty multiparous (second and third lactation) Holstein–Friesian cows were selected that had 81 ± 12 days in milk and produced 15.08 ± 1.20 kg of milk/day. Two groups were created for the experiment: control (CTL; n = 20) and experimental (LC; n = 20). The experiment was divided into two periods: an initial period lasting 7 days in which the experimental group was habituated to the new supplement in their diet; the proper experimental phase, lasting 6 weeks, in which the cows in the experimental group received an individual daily dose of linseed cake (300 g/day/cow). Linseed cake supplementation had a positive impact on the levels of bioactive components (fatty-acid profile and fat-soluble vitamins) in the milk fat fraction. At the end of the trial, the concentration of C18:2 cis9 trans11, C18:1 trans11, α-retinol, α-tocopherol, and total antioxidant status increased 1.59-, 1.94-, 3.12-, 3.38-, and 3.09-fold, respectively, relative to the control levels. The use of linseed cake in winter on organic farms makes it possible to increase the antioxidant potential of milk, thereby eliminating the disparity in the quality of milk from the summer season compared to the winter season.

A b s t r a c t The aim of this study was to develop an effective method of overwintering reserve honey bee queens in two-storey mini-plus mating nuclei and in 3-comb nuclei (frames 36 x 26 cm, Wielkopolski hive). The assay was performed during three wintering seasons (2005 -2008) parallel at two centers in Poland: the Division of Apiculture at the University of Life Sciences (SGGW) in Warsaw, and the Apiculture Division at the University of Warmia and Mazury (UWM) in Olsztyn. The results showed that 59% of queens overwintered in mini-plus nuclei and 77% in 3-comb nuclei. Among queens in mini-plus nuclei 63% overwintered in bee yard and only 55% in cellar. Within queens in 3-comb nuclei, 62% overwintered in Olsztyn and 91% in Warsaw. The highest survival rate of 93% was observed in Warsaw during the first season. Due to low survival rate, it is not recommended to overwinter the queens in miniplus nuclei.

The aim of the study was to evaluate the variability of morphological characteristics of native middle-European bees (Apis m. mellifera) of the ‘Northern M’ line. The research covered characteristics of breed (the length of proboscis, the cubital index), body size (the width of tergite 4 and the sum of widths of tergites 3 and 4) and wing size (length and width). The study compared bees harvested from a leading apiary and from collaborating apiaries participating in a program for the protection of genetic resources of bees of this line. The material for the study was harvested in 10 consecutive years. The samples were collected by the “cluster drawing” method (the multi-stage method of clustering described by Zee et al. in 2013). Each sample consisted of 25 to 30 bees. The frames were loaded in an instrument for the morphological measurement of bees (Apimeter). Seven measurements were taken on prepared body parts of each bee. The length and width of the wing and the length of the cubital vein were measured on the right front wing (hereinafter referred to as the “wing”). In addition, the width of abdominal tergites 3 and 4 and the length of proboscis were measured in each instance. In total, 4 291 bees were harvested and 30 037 measurements were taken. The conclusion is that the program for the protection of genetic resources of bees of the ‘Northern M’ line can be implemented in Poland based on the leading apiary and on the collaborating apiaries, and bees of this line display characteristics of middle-European bees. Moreover, the study demonstrated a consistency of values of the studied characteristics of the ‘Northern M’ line with the applicable references of morphological characteristics for Apis m. mellifera. In addition, based on a review of results of the author’s research and based on collected literature originating from the 1960s, the study proves that a dwarfing trend has emerged among middle-European bees.