[Relation of lactose levels in milk and indicators of mammary gland health in the first third of lactation].

A total of 662 bucket milk samples from cows of two breed groups were examined: red and white breed = Bohemian Pied cattle with different genetic proportions of Ayrshire and Red Holstein improvement breeds; black and white breed = Black and White Lowland breed and different degree of absorptive crossing with a genetic proportion of the Holstein breed. Samples of daily milk yields were taken in the first three months of lactation once a month within a year. A possibility of using lactose content as an auxiliary indicator for detection of the mammary gland secretion disorders in the initial lactation stage was evaluated.

[The effect of aging of milk samples on the accuracy of infrared analysis of milk composition].

The effect of a decrease (and/or fermentation) in the lactose content during milk storage under different conditions was investigated on the accuracy of the results obtained on a Milko-Scan apparatus to contribute to the present knowledge of this problem. The results were in agreement with some results cited in the literature. These wavelengths are used for infrared spectrophotometry on the above apparatus: for fat 3.

[Comparison of the effectiveness of Milkofix, a preservative preparation, with traditional preservative agents in the determination of somatic cell count in milk samples using a fluoro-optic-electronic method].

Milkofix (M), a health friendly preservative substance, to be used for milk sample preservation (Trzický, 1990), was compared with other preservatives. Untreated milk samples (N) were tested against samples treated with sodium azide (A; 0.0085 g NaN3 and 0.

[Testing Milkofix, a new preservative preparation for milk samples used for infrared analysis of milk components. II. Verification of its preservative effects in relation to infrared analysis].

For the purposes of the infrared analysis of the basic milk composition, Milkofix, an ecologically friendly preparation used for milk sample preservation (Trzický, 1990), was compared with untreated samples (N) and with samples preserved with sodium azide (A), bronopol (B) and potassium dichromate (C) at a storage temperature of 20 degrees C (I) and 4 degrees C (II) in samples kept for 14 and 18 days. Pursuant to the recommendations cited in literature, the preservatives had these concentrations: A = 0.0085 g NaN3 and 0.

[Tests of Milkofix, a new preservative preparation for milk samples used for infrared analysis of milk components. I. Verification of its bacteriostatic and bacteriocidal effects and its interference effects].

Hygienic, ecological and health problems of sample preservation for an analysis of basic milk components make us continually to develop a safer chemical preservative substance which will preserve the original sample composition for the time required and which will not influence the analyses. Trzický (1990) proposed Milkofix (M), a preservative substance on the basis of silver compound. The author reports on minimum risks of the use of this preparation, in comparison with traditional preservatives.