RU2804852C1 - Prevention of mastitis in lactating cows - Google Patents

Abstract

FIELD: veterinary medicine.

SUBSTANCE: invention is related in particular, to a method for preventing mastitis in lactating cows. The method includes the use of an immunomodulator. Proautovac drug is used as an immunomodulator, which is administered from the first day after calving three times with a 24-hour interval at a dose of 10 ml per animal.

EFFECT: invention makes it possible to increase the efficiency of prevention of mastitis in cows during lactation.

1 cl, 6 tbl

Description

The invention relates to veterinary medicine, in particular to veterinary obstetrics, and can be used to prevent mastitis in lactating cows.

The relevance of the proposed method is determined by the high incidence of mastitis in lactating cows, which has recently tended to increase and amounts to up to 80% [Ekhorutomven O.T., Medvedev G.F., Stukina A.I. Causes, frequency of mastitis in cows and their milk productivity // Animal husbandry and veterinary medicine. 2022. No. 1 (44). - P. 7-11].

The main factors contributing to the occurrence and development of mastitis are the technical imperfection of milking installations, violation of the technology and rules of machine milking of cows. At the beginning, irritation occurs, which, when repeated many times, turns into latent aseptic inflammation. General and local resistance is reduced, conditions are created for the penetration and reproduction of various opportunistic and pathogenic microflora in the tissues of the mammary gland, which causes the development of inflammation in a subclinical form, which occurs independently over one or two lactations and leads to atrophy, or transforms into clinical severe (serous, catarrhal, purulent-catarrhal, etc.) mastitis. To date, more than 100 different types of microorganisms have been isolated from the secretions of the mammary gland of cows with mastitis [Immunological aspects of the fight against cow mastitis / V.I. Slobodyanik, N.T. Klimov, L.V. Cheskidova, E.V. Zverev. - Voronezh: Istoki Publishing House, 2020. - 222 p.].

Currently, mainly foreign-made vaccines (Mastivak, Startvak, Vakolin) are used to prevent mastitis in lactating cows. However, they do not always give the desired effect, since they are specific only to 2-4 of the microorganisms that have etiological significance [Tarasenko M.N. Improving methods for preventing mastitis in highly productive cows: 02/06/02; diss. ...cand. vet. Sci. - Yekaterinburg, 2016. - 172 p.]. In connection with the increased requirements for the quality of milk and the widespread distribution of drug-resistant strains of microorganisms that cause the development of mastitis, it is necessary to further study new drugs that stimulate the general nonspecific resistance of the body, factors of local protection of the mammary gland of cows, and thereby eliminate the inflammatory process in the mammary gland or prevent its occurrence in clinically healthy animals.

Such drugs include immunomodulators - drugs that affect the activity of the immune system and, in accordance with the existing classification, the following groups of immunomodulators are distinguished: drugs based on natural factors (immunoglobulin drugs, peptide drugs, drugs based on cytokines, drugs of microbial origin, etc.) and synthetic drugs (cyclic compounds, synthetic analogues of natural immunomodulators, etc.) [Yarilin A.A. Fundamentals of immunology. M.: Medicine, 1999. - 608 pp.].

There is a known method for the prevention and treatment of mastitis in cows, including intracisternal administration of an antimicrobial substance with oxygen. Ozonated refined deodorized vegetable oil is used as an antimicrobial substance in a dose of 10-20 ml, and the injection is carried out into each quarter of the udder on the 4th day of launch and 1-15 days before calving [RU 2201756 C2, A61K 33/00, A61K 35 /78, 04/10/2003 Bulletin. No. 10].

The disadvantage of this method of preventing mastitis in cows is that the drug is used only for dry cows (two months before calving).

There is a known method for the prevention and treatment of mastitis in cows, which involves the introduction of a tissue preparation, which is used as a filtrate of the mammary gland extract of healthy animals, stabilized with mannitol. For prophylactic purposes, the drug is administered twice 20-30 and 10 days before calving subcutaneously at a dose of 0.1-0.2 ml per kg body weight [RU 2201758 C2, A61K 35/48, A61P 15/00, 04/10/2003 Bulletin . No. 10].

The disadvantage of this method of preventing mastitis in cows is that industrial production of this drug has not been established and it is prepared independently (handicraft), as a result of which each batch differs in biological activity and, therefore, effectiveness.

There is a known method for the prevention of mastitis in cows, which involves the monthly use of bovine recombinant α- and γ-interferons, which are administered intramuscularly at a dose of 2.5 ml with an interval of 24 hours monthly from the first day after calving [RU 2683289 C1, A61K 38/21, A61P 15 /00, 03/27/2019 Bulletin. 9].

The disadvantage of this method is the repeated monthly administration of the drug and low preventive effectiveness.

The closest analogue, taken as a prototype, is a method for the prevention of mastitis in lactating cows, involving the use of the immunomodulator Imunofan, which is administered intramuscularly from the first day after calving in a dose of 5 ml per animal three times with an interval of 48 hours and repeated quarterly [RU 2731476 C1, A61D 99/00, 09/03/2020 Bulletin. 25].

The disadvantages of this method are the high labor costs for repeated administration of the drug, as well as its insufficient preventive effectiveness.

The technical result of the invention is to increase the effectiveness of the method for preventing mastitis in lactating cows while reducing the frequency of administration of the immunomodulatory drug and, as a result, reducing labor costs.

The technical result is achieved by the fact that in the method of preventing mastitis in cows during lactation, including the use of an immunomodulator, according to the invention, the drug Proautovac is used as an immunomodulator, containing in 1 ml bovine recombinant α- and γ-interferons with a total activity of at least 1000 IU, bovine recombinant GM-CSF - 0.005 mg, vitamin A - 25000 IU, vitamin E - 25 mg, vitamin C - 50 mg, sodium benzoate - 0.5 mg, polyethylene glycol - 0.1 ml and water for injection - up to 1 ml, Moreover, Proautovac is administered to cows from the first day after calving three times with a 24-hour interval at a dose of 10 ml/animal.

Proautovac is an immunomodulator with antioxidant and immunocorrective effects. A mixture of α- and γ-interferons of bovine recombinants acts as an inducer of bactericidal and lysozyme activity in blood serum, has an anti-inflammatory effect, increases the resistance of the animal body to the effects of DNA and RNA containing viruses and pathogenic microorganisms, exhibits an anti-stress effect, increases immune tension and relieves post-vaccination syndrome during vaccinations.

GM-CSF (granulocyte-macrophage colony-stimulating factor) - participates in the regulation of physiological and biochemical functions of various body systems at the gene level. GM-CSF is involved in hematopoiesis, differentiation of myeloid cells, affects the functional activity of immunocompetent (lymphocytes, macrophages, neutrophils, dendritic cells) and tissue cells. GM-CSF and its recombinant forms are used in hematology, immunology, oncology, reproductology and in the treatment of systemic autoimmune processes and infectious diseases [Immunobiological properties of granulocyte-macrophage colony-stimulating factor and synthetic peptides of its active center / A.V. Zurochka, V.A. Zurochka, M.A. Dobrynina, V.A. Gritsenko // Medical immunology. 2021. T. 23, No. 5. - P. 1031-1054].

Vitamin A is involved in redox processes, regulation of the synthesis of proteins, sex hormones, interferon, immunoglobulin A and lysozyme; promotes normal metabolism, the function of cellular and subcellular membranes, plays an important role in the formation of bones and teeth, fat deposits; necessary for the growth of new cells, slows down the aging process.

Vitamin E, being one of the most powerful natural antioxidants, inhibits the development of free radical reactions, prevents the formation of peroxides that damage cellular and subcellular membranes, which is important for the development of the body, the normal function of the nervous and muscular systems. Tocopherol is an antihypoxant, which is explained by its ability to stabilize the mitochondrial membrane and save oxygen consumption by cells.

Vitamin C performs the biological functions of a reducing agent and a coenzyme of certain metabolic processes; participates in the formation of collagen, serotonin, catecholamines, the synthesis of corticosteroids, the conversion of cholesterol into bile acids, restores ubiquinone and vitamin E, stimulates the synthesis of interferon.

Sodium benzoate is used in medicines as a preservative.

Polyethylene glycol is used as a solvent, stabilizer, viscosity regulator, and binder.

Water for injection is used as a solvent in the preparation of dosage forms.

We explain the essence of the technical solution with examples.

During the research, 35 fresh cows were included in the experiment. Cows of the first group (n=12) were injected with the drug Proautovac three times with a 24-hour interval at a dose of 10 ml per animal, starting from the first day of the postpartum period, the second (n=12) - Biferon-B three times with a 24-hour interval at a dose of 5 ml per animal, the third (n=11) were not administered any drugs; they served as a negative control.

On the 14th day after calving, the animals included in the experiment were subjected to a diagnostic test for mastitis with a 2% Masttest solution and a clinical examination, the results of which determined the effectiveness of the use of drugs for the prevention of postpartum mastitis.

It was found that in the negative control group 18.2% of animals developed catarrhal mastitis (Table 1). After double administration of Biferon-B, catarrhal mastitis was recorded in 8.3% of cows. When Proautovac was administered three times, 8.3% of cows also developed mastitis, but the inflammation occurred in a subclinical form.

In addition, blood and milk samples were taken from cows from each group before the administration of drugs and on the 14th day after calving for laboratory tests.

The results obtained by studying changes in the morphological, biochemical and immunological status of cows on the 14th day after calving are presented in Table 2.

It was found that in animals that were administered Biferon-B, compared with animals in the negative control group on the 14th day after calving, the content of leukocytes was lower by 21.9%, eosinophils - by 32.8%, band neutrophils - by 28.7% , monocytes - by 22.2%, total immunoglobulins - by 18.3%, circulating immune complexes (CIC) - by 33.3%, with an increase in serum lysozyme activity (LAS) by 23.5%, phagocytic index (PI ) - 1.5 times and phagocytic number (PN) - 1.6 times.

After using Proautovac, changes in indicators of morphological, biochemical and immunological status are more pronounced. Thus, the content of leukocytes was lower by 27.1%, eosinophils - by 43.1%, band neutrophils - by 36.1%, monocytes - by 33.3%, total immunoglobulins - by 19.8%, circulating immune complexes - by 25.6%, with an increase in the level of lysozyme activity of blood serum - by 41.2%, the phagocytic index - by 1.7 times and the phagocytic number - by 1.8 times, which indicates the activation of the general nonspecific resistance of the body of cows.

The results of studying changes in the level of endogenous intoxication in cows on the 14th day after calving when using immunocorrective drugs are presented in Table 3.

It was found that in cows that were administered Biferon-B, compared with animals in the negative control group on the 14th day after calving, the concentration of malondialdehyde (MDA) was lower by 21.8%, average weight molecules (MSM) - by 27.2% , with an increase in catalase activity by 22.0% and glutathione peroxidase (GPO) by 48.5%.

After using Proautovac, a decrease in the level of malondialdehyde was recorded by 24.0%, nitric oxide metabolites ( _NOx ) by 21.4%, average weight molecules by 31.7% and the endogenous intoxication index (IEI) by 24.8%, with an increase in the concentration of vitamin E by 35.5%, vitamin C by 32.9%, catalase activity by 27.5% and glutathione peroxidase by 53.6%, which indicates a decrease in endogenous intoxication and simultaneous activation of the enzymatic and non-enzymatic components antioxidant protection.

Indicators of udder secretion of cows after the use of immunocorrective drugs for the prevention of mastitis are presented in Table 4.

It was found that in the milk of animals of all groups before the start of the experiment, the content of somatic cells (SC), total immunoglobulins, circulating immune complexes and lysozyme corresponded to the indicators of clinically healthy animals and did not differ significantly between groups.

Two weeks from the start of the experiment, in the remaining clinically healthy animals of all groups, the indicators of udder secretion also corresponded to the indicators of clinically healthy animals. At the same time, in the milk of animals treated with Biferon-B, in relation to animals in the control group, a lower content of circulating immune complexes was noted by 36.3% and somatic cells by 32.9%.

More pronounced changes compared to the control group were noted with the use of Proautovac: a decrease in the content of circulating immune complexes by 44.7% and somatic cells by 46.1%.

The species composition of the microflora 1-2 hours after calving and 14 days after birth when using immunocorrective drugs is presented in Table 5.

Bacteriological studies of colostrum samples from new-calf cows of the control group identified pathogenic Staphylococcus aureus in association with Escherichia coli and Staphylococcus epidermidis in 40.0% of cases, and pathogenic Agalactic streptococcus in various associations with Staphylococcus epidermidis and Escherichia coli in 60.0% of cases. During the period of the experiment, no changes were noted in the microflora of the milk of cows of the third group.

Before the start of the experiment, the mammary gland of animals of the second group was contaminated in 60.0% of cases with pathogenic Staphylococcus aureus in combination with E. coli and enterococcus, and in 40.0% with pathogenic agalactic streptococcus in various associations with E. coli and enterococcus. At the end of the experiment, E. coli was isolated from the mammary gland in 60.0% of cases.

The mammary gland of animals of the first group (Proautovac) on the first day after calving was contaminated in 60.0% of cases with Staphylococcus aureus in association with Escherichia coli, Staphylococcus epidermidis and Enterococcus, in 40% with Agalactic streptococcus in association with Staphylococcus epidermidis and Enterococcus. 14 days after using Proautovac, Escherichia coli, Staphylococcus aureus and Streptococcus agalactii were not isolated; enterococcus was isolated from 40.0% of animals.

Changes in bacterial contamination of milk when using immunocorrective drugs for the prevention of mastitis are presented in Table 6.

The degree of microbial contamination of milk from animals in the control group did not change significantly during the study period.

In the group of animals treated with Biferon-B, there was a 3.1-fold decrease in milk contamination with microflora. In the group of animals treated with Proautovac, contamination of milk with microflora decreased by 8.7 times.

At the end of the study, in animals that were administered Biferon-B, bacterial carriage in the mammary gland was established in 60.0% of animals treated with Proautovac - in 40.0%, and in the control group - in 100.0%.

Consequently, double administration of Biferon-B to fresh cows at a dose of 5 ml from the first day after calving ensures a 3.2-fold reduction in microbial contamination of milk and reduces the number of bacteria carriers by 1.7-fold.

The most pronounced effect was exerted by the use of Proautovac; its three-time use in a dose of 10 ml with a 24-hour interval from the first day after calving ensured a reduction in microbial contamination of milk by 5.4 times, and contributed to a reduction in the number of bacteria carriers by 2.5 times.

Thus, three-time administration of Proautovac to cows at a dose of 10 ml per animal with a 24-hour interval, starting from the first day of the postpartum period, reduces the incidence of postpartum mastitis by 2.2 times due to the reduction of endogenous intoxication, lipid peroxidation while simultaneously activating antioxidant protection and general nonspecific resistance of the body of cows.

Claims (1)

A method for the prevention of mastitis in cows during lactation, including the use of an immunomodulator, characterized in that the drug Proautovac is used as an immunomodulator, containing in 1 ml bovine recombinant α- and γ-interferons with a total activity of at least 1000 IU, bovine recombinant GM-CSF - 0.005 mg, vitamin A - 25000 IU, vitamin E - 25 mg, vitamin C - 50 mg, sodium benzoate - 0.5 mg, polyethylene glycol - 0.1 ml and water for injection - up to 1 ml, and Proautovac is administered to cows from the first days after calving three times with a 24-hour interval at a dose of 10 ml/animal.