Routine tests of milk composition and quality

Milk fatty acid analysis

Milk fats are formed from two sources. Approximately 50% of bovine milk fats are synthesized from feed, so by changing feeds and creating optimal conditions for the activity of rumen microorganisms, it is possible to alter the composition of milk fats.

Results of research conducted by scientists from the Veterinary Academy of the Lithuanian University of Health Sciences, related to the impact of feeding on the composition of milk fats, showed that the milk from pasture-grazed cows was more valuable than that of cows fed solely with feed mixtures, as it contained more polyunsaturated fatty acids essential for the human body.

As doctors claim, these acids are crucial for the prevention of cardiovascular diseases, inhibit the development of atherosclerosis, suppress inflammatory processes and diabetes.

Milk fats consist of more than 400 different fatty acids. The majority is composed of saturated fatty acids (65-70%). Monounsaturated fatty acids account for 27-33%, primarily oleic acid. Polyunsaturated fatty acids make up 3.5-5%, and milk fats are relatively rich in short-chain saturated fatty acids (10%).

The laboratory identifies these important groups of fatty acids:

Saturated Fatty Acids (SFA)
Unsaturated Fatty Acids (UFA)
Monounsaturated Fatty Acids (MUFA)
Polyunsaturated Fatty Acids (PUFA)

The analysis includes categories of fatty acids: de novo, mixed origin and pre-formed acids.

You can order the analysis along with a commercial milk composition test. Just write + fatty acids (FA) on the invoice or add an additional request.

For those with a contract, the cost of the milk composition and fatty acid analysis is only €1.69 excluding VAT (€2.05 including VAT). For those without a contract, the cost is only €2.43 excluding VAT (€2.94 including VAT).

Determination of fat, protein, lactose, urea content, pH and somatic cell count

Test of fat, protein, lactose, urea content and pH is carried out with mid-infrared analyser LactoScope FTIR. Test of somatic cell count is carried out with Somascope analyser working on the basis of flow cytometry method.

Total bacteria count analysis

Total bacteria count is determined through flow cytometry method by using Bentley Bactocount IBC analyser.

Inhibiting substance analysis

Delvotest SP-NT test is a standard wide-range diffusion test for determination of inhibiting substances in the milk. The method is based on the fact that proliferation of Geobacillus stearothermophilus var. calidolactis spores that are sensitive to antibiotics and sulphamides leads to the formation of acid that changes the colour of the medium from violet to yellow. This method allows detection of penicillin of more than 4 µg/kg and sulphamides as well as other content of antibiotics specified by the company manufacturer. Delvotest SP-NT sensitivity to antibiotics is provided by the manufacturer in Technical Bulletin issued on 26 January 2016.

Identification of antimicrobial substances

In carrying out tests of raw cow’s milk for safety and quality monitoring and control and detection of inhibiting substances through the microbiological method, Delvotest, from 02.05.2019 antimicrobial substances are identified in raw milk samples through a modified immunoenzyme analysis method by using InfiniPlex test (504MET26:2019, issue 1, approved on 02.05.2019).

Antimicrobial substances are medicinal preparations, such as antibiotics, anti-inflammatory substances, anthelmintics, toxins and other residues inhibiting the growth of micro-organisms. Immunoenzyme test with chemiluminescence by using automated biolust technology is based on the competition of antimicrobial substance with antibodies adsorbed into separate areas of biolust. The method is qualitative, test results are expressed respectively: no residues of antimicrobial substances have been detected or one or several specific antimicrobial substances have been identified.

List of antimicrobial substances determined through InfiniPlex test for milk was approved by manufacturer of the test – Randox Laboratories Ltd (United Kingdom) on 17.04.2019.

Test of milk freezing point

Test of milk freezing point is carried out with Lactoscope FTIR analysers. This method for determination of milk freezing point is assigned to the sorting method and is used to select the samples with suspected presence of side water, i.e. the freezing temperature is above minus 515 moC. The exact freezing point of milk samples is determined by analysing the selected samples with thermistor cryoscope method according to LST EN ISO 5764:2009.

Polymerase chain reaction (PCR) test for causative agents of mastitis according to the DNA

PCR is a very precise, fast and sensitive method where the DNA of mastitic agent is extracted.

It is possible to find out the prevalence of cows infected with:

  • Staphylococcus aureus,
  • Streptococcus agalactiae,
  • Streptococcus uberis,
  • Mycoplasma bovis,
  • ß-Lactamase gene (blaZ gene),
  • Coagulase Negative staphylococcus (CNS),
  • Streptococcus dysgalactiae,
  • Other mycoplasma species,
  • Escherichia coli,
  • Escherichia coli,
  • Klebsiella,
  • Prototheca,
in the herd from the bulk tank milk sample.
Container sample   Causative agents   DNR - PCR   Prevalence in the herd

This method is extremely useful not only for its precision, but also for a possibility to determine the prevalence of infected cows in the herd by analysing the bulk tank milk sample!!!

Evaluation of the prevalence of infected cows in the herd according to the Ct value
Auksinis stafilokokas   Kiti sukėlėjai
Ct reikšmė Papiltimas, %   Ct reikšmė Paplitimas, %
Ct ≥ 37 nėra   Ct ≥ 37 nėra
34 ≤ Ct < 37 <5%   30 ≤ Ct < 37 <5%
25 ≤ Ct < 34 5-25%   25 ≤ Ct < 30 5-25%
Ct < 25 >25%   Ct < 25 >25%

UAB Pieno tyrimai carries out laboratory PCR tests to determine the presence of 12 microorganisms (Streptococcus uberis, Streptococcus agalactiae, Staphylococus aureus, Mycoplasma bovis, etc.) in the selected bulk tank milk sample. These tests are carried out through an innovative molecular polymerase chain reaction method (PCR) that is widely applied in the diagnostics around the world enabling fast and precise determination of udder infection at its very start as well as evaluation of the prevalence of micro-organisms in the herd.

Determination of causative agents of mastitis and their sensitivity to antibiotics

Mastitis caused by various pathogens can manifest in various forms and it is also complicated to identify the causative agent responsible for the specific case of mastitis. Mastitis always requires fast and effective treatment in order for the cow to be able to give a considerable amount of good quality milk in the future. To reduce the treatment costs and to achieve the best results, it is particularly important to evaluate the pathogens of causative agents of mastitis. UAB Pieno tyrimai determines the type of agent of mastitis and pathogenicity from the cow’s milk, forms antibiograms – the sensitivity of causative agent to separate groups of antibiotics, selects the most appropriate medication. It consults on the matters of treatment and evaluates the effectiveness of the treatment of cow after the treatment course according to the results of somatic cell count test.

The milk sample for determination of causative agents of mastitis can be taken by the owner of the cow or the veterinary doctor according the owner’s request. We recommend to use the containers prepared by UAB Pieno tyrimai with a preservative (blue coloured) that can be ordered in advance. The samples of milk may be delivered straight to the laboratory of UAB Pieno tyrimai or handed over to the driver of the laboratory. For any additional information, please contact the information manager (ph.: 8 37 363653, mob. ph. 8 687 15553). Samples have to be taken as described and the cover letter for the determination of causative agents of mastitis shall be filled.

Sampling for determination of causative agents of mastitis and their sensitivity to antibiotics

      1. The sample of milk is taken from each quarter of udder into a sterile container or containers with a preservative (blue coloured) prepared by the laboratory for the determination of presence of causative agent of mastitis. The sample should be taken at the start of milking. The 40 ml sample shall be labelled according to the procedure:
      2. The udder shall be dry and clean. Please wash and disinfect your hands before taking the sample.
      3. Clean the tips of teats. Clean the tip of each teat with a cotton or a gauze soaked in 70% alcohol solution or any other disinfectant.
      4. Start the sampling from the closest teat by milking 4-5 streams of milk from each teat. This allows to avoid bacteria from inter-channel, as the sample from the milk gland is necessary.
      5. By holding the test-tube in a hand, remove the cover without contaminating it. Do not place the cover on the floor or any other surface to avoid contamination.
      6. Keep the test-tube angled to prevent the contact with the tip of the teat. After taking the sample, close the container quickly and tumble several times.
      7. Cold-kept samples shall be delivered to the laboratory within 12 hours from sampling. The samples of milk may be delivered to the laboratory by a customer himself or handed over to the driver of UAB Pieno tyrimai.

IMPORTANT: when taking milk samples from more than 1 animal, it is necessary to disinfect and wash hands to avoid transferring any infection to another animal and contaminating the sample.

  • The causative agents of mastitis identified in the laboratory include Staphylococcus aureus, coagulase-negative staphylococci (CNS), Streptococcus agalactiae, groups set for other streptococci according to Lancefield classification (A, B, C, D, F, G), Escherichia coli, etc.
  • The sensitivity of causative agents of mastitis to amoxicicline, amoxicicline with clavulanic acid, cephalexin, enrofloxacin, gentamicin, neomycin, cloxacilllin, kanamycin, penicillin, ampicillin, streptomycin, bacitracin, lincomycin, tetracycline is evaluated. The list of indicated antibiotics is subject to change.

The test for causative agents of mastitis is carried out and their sensitivity to antibiotics is determined by using a method based on the ability of causative agents of mastitis to form the characteristic colonies on a solid agarised nutrition medium which are then tested by identifying the type of the causative agent and their sensitivity to individual antibiotics through a disk diffusion method.

The results of the tests performed are presented to the customer by issuing a document of a specified form – test protocol in a way coordinated with the customer (sent by e-mail, regular mail, handed over when taking other milk samples from the customer). In case of need to receive test results by regular mail, the customer must cover the postal costs.

Find out the in-calf cows and not-in-calf cows

Easy - Fast - Precise

Test from the milk is the easiest way to find out and detect in-calf and not-in-calf cows

The determination of in-calf cows from milk through immunoenzyme method by using the Alertys Milk Pregnancy test allows to avoid contact between the animals through diagnostic tools. Intervention methods for determination in-calf cows (rectal palpations, ultrasound) ensure precise (up to 98%) determination of pregnant cows. However, these are the most expensive methods as well, taking into account the price of specialised veterinary services. Furthermore, in case of complicated pregnancy, the application of these methods may lead even to the embryonic mortality.

1-minute video about milk pregnancy test

Sets of feed tests 


- includes at least such indices as dry matter, raw ash, digestibility of organic matter, raw protein, raw fibres, raw fats, sugar, starch, fibre washed in neutral solution, evaluation of nutritional value according to the German system, evaluation of forage value according to the Danish and NorFor systems.

The test is carried out with near-infrared spectrometer (NIRS method).


- in addition to parameters listed in the standard set, this also includes at least such indices as active acidity (pH), acetic acid, lactic acid, ammonia content, nitrates, soluble raw proteins, starch non-degradable in the forestomach, fibre washed in neutral solution – digestibility, fibre washed in neutral solution without nitrogen, acid-washed fibre and acid-washed lignine, chlorides.

Feed nutritional value analysis via Eurofins Agro (BLGG, the Netherlands)

Professional + recommendations

- presentation of metabolism energy and digestibility characteristics, influence of feed on the production of milk, recommendations for silos preparation, adjustment of ration.
1. The sample shall be taken from 4-5 different places of the tested area (4-5 kg) and shall be mixed well.
2. 1 kg of mixed feed shall be separated and placed into a bag.
  • After the feed is placed into the bag, please remove the air from the bag first and then seal it by removing the protective strip.
  • Do not take the sample from the rotten part of the feed.
  • The samples shall be taken only after the completion of fermentation process.

Address: Radvilu Dvaro str. 31
LT-48331, Kaunas, Lithuania
Phone: (+370 37) 361181

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