The milk freezing point (MFP) is used for the control of milk food chain quality especially for possible adulteration with water. A crucial issue is the acceptance of the legislative discrimination limit (RLDL) of MFP for standard quality. The aim was to explain the relations between MFP and spectrum of milk indicators (MI) and possible impacts of MFP on technological milk properties. 76 bulk milk samples (BMS) from Holstein (1, <I>n</I> = 36) and Czech Fleckvieh (2, <I>n</I> = 40) cattle were analyzed for 48 MIs. The dairy cows were relatively healthy as for the occurrence of production disorders. BMSs were taken from February to June. Extraneous water was excluded. 44 MIs were correlated with the MFP. The relations were not regularly consistent between breeds. Milk yield was connected with MFP (<I>r</I> = 0.40; <I>P</I> < 0.05). It shows the necessity of modification of RLDL of MFP in dependence on dairy cow breeding. Further relations (<I>P</I> ≤ 0.05) were among MFP and: total milk solids (<I>r</I> = –0.50); solids-non-fat (–0.33); crude protein (–0.32); true protein (–0.43); whey protein (–0.47); milk fat (–0.46); electrical conductivity (–0.35); lactose (–0.35); somatic cell count (–0.36); fat/protein ratio (–0.36); milk citric acid (0.47); Na (–0.34). The poor relations (<I>P</I> > 0.05) were among MFP and casein, milk urea and acetone. The cheese-making indicators were not affected by MFP. The MFP was related to milk fermentation indicators (<I>r</I> = from –0.34 to –0.39, <I>P</I> < 0.05). It is important for the control of milk food chain quality by MFP and for the estimation of its RLDL.

Abstract. 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, P < 0.05). The effect of breed was found in odd-chain, branch-chain and hypercholesterolemic FAs (P < 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 (P < 0.05). The proportion of saturated and polyunsaturated FAs was lower in S than in W (P < 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 , P < 0.05). Milk yield in grazing herds (G, 5197.50 kg) was lower (P < 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 (P < 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, P < 0.001).

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The possible genetic impact of sire on cattle populations, herd milk yield and milk traits (fat and protein) have been described in the literature along with its impact on some milk indicators (MIs) as somatic cell count, urea and ketones. There is a dearth of information on the impact on a series of other MIs (physical, chemical, health, technological). The goal of this study was to assess the possible effect of sire on a wide range of MIs including technological properties in Czech Fleckvieh to suggest future possible breeding trends. A series of MIs (n=37) was investigated in individual milk samples (MSs). 191 effective daughters (MSs) were included. The sire groups (n=13) were well balanced in terms of herd, lactation stage and sampling season. Only sires with >5 daughters were ranked. A linear model of analysis variance with the fixed effects, sire and combined factor (herd × year × season) was used. 19 MIs as log count of streptococci in fermentation ability of milk (log FAM-CS), FAM-CS, log total fine microflora count in FAM (log FAM-TCM), FAM-TCM, solids non fat (SNF), iodine content, citric acid (CA), titration acidity in FAM, lactose (L), crude protein (CP), true protein (TP), casein (CAS), dry matter, Mg and P content, milk alcohol stability, electrical conductivity (EC), titration acidity, casein numbers (for CP and TP), log count of lactobacilli in FAM (log FAM-CL), FAM-CL and pH in FAM were influenced by sire (P<0.05). However SNF, CA, L, CAS and perhaps EC could be newly reflected as information for genetic improvement of dairy cattle with connection to dairy milk recovery and cow health. CA (10.08±1.92 mmol×l −1 ) deserves special attention. The model variablity explanation moved from 6.97 (SCC) over 29.51 (CA) to 48.32 % (pH) for MIs. This is one of few studies to assess the impact of sire over a wide range of MIs and the results warrant careful evaluation and further study.

The milk analyse result reliability is important for assurance of foodstuff chain quality. There are more direct and indirect methods for milk composition measurement (fat (F), protein (P), lactose (L) and solids non fat (SNF) content). The goal was to evaluate some reference and routine milk analytical procedures on result basis. The direct reference analyses were: F, fat content (Röse-Gottlieb method); P, crude protein content (Kjeldahl method); L, lactose (monohydrate, polarimetric method); SNF, solids non fat (gravimetric method). F, P, L and SNF were determined also by various indirect methods: -MIR (infrared (IR) technology with optical fi lters), 7 instruments in 4 labs; -MIR-FT (IR spectroscopy with Fourier's transformations), 10 in 6; -ultrasonic method (UM), 3 in 1; -analysis by the blue and red box (BRB), 1 v 1. There were used 10 reference milk samples. Coeffi cient of determination (R 2 ), correlation coeffi cient (r) and standard deviation of the mean of individual diff erences (MDsd, for n) were evaluated. All correlations (r; for all indirect and alternative methods and all milk components) were signifi cant (P ≤ 0.001). MIR and MIR-FT (conventional) methods explained considerably higher proportion of the variability in reference results than the UM and BRB methods (alternative).