Respiratory mycoplasmosis of calves and piglets. Mycoplasmosis of young animals: epizootology, diagnosis and treatment. Sources and routes of infection

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8.4. Mycoplasma mastitis

Pathogen – Mycoplasma bovigenitalium, Mycoplasma agalactiae var. bovis (M. bovimastitidis) belong to the genus Mycoplasma.

In sick cows, the udder lobes are hard and swollen, and milk production is sharply reduced. When settling, milk quickly separates into two fractions: liquid and dense. The general condition of the cows is satisfactory.

Mycoplasma mastitis is difficult to treat. In some animals, the disease lasts for one year or more, and mycoplasmas are systematically found in milk, joints, blood, internal organs, and even in aborted fetuses.

Cows from the herd suffering from mastitis must be isolated and assigned to separate staff.

8.5. Mycoplasma arthritis of calves

Pathogen – Mycoplasma bovigenitalium, Mycoplasma agalactiae var. bovis (M. bovimastitidis), Mycoplasma bovirhinis, mycoplasma bovis belong to the genus Mycoplasma.

Clinically, the disease is manifested by a stiff gait, lameness, loss of appetite, fever, enlargement of the wrist, hip and knee joints.

It is believed that arthritis may be the main systemic manifestation of mycoplasma mastitis in dairy cattle, and that young non-lactating animals subsequently become ill.

Arthritis in animals is associated with respiratory diseases and most often occurs against a background of stress.

8.6. Mycoplasma conjunctivitis of cattle

The causative agent – ​​Mycoplasma bovirhinis, mycoplasma bovis, mycoplasma oculli belong to the genus Mycoplasma.

Many diseases caused by mycoplasmas are often accompanied by keratitis and keratoconjunctivitis: mastitis and arthritis of cattle.

8.7. Immunity against mycoplasmosis in cattle

After recovering from the disease and vaccination, animals acquire active immunity.

Mycoplasma infections are latent, or chronic infections; however, infected organisms typically exhibit symptoms of immunodeficiency. In the mammalian body, mycoplasmas, like other infectious agents, trigger specific and nonspecific immune reactions. The results of studies of the characteristics of the reaction of immunocompetent cells to mycoplasma infections indicate that the interaction of mycoplasmas with the mammalian immune system can lead to immunopathology associated with nonspecific stimulation or inhibition of immunocytes, as well as autoimmune reactions as a result of a breakdown in tolerance to the host’s own antigens.

The characteristic morphological features of mycoplasmas, their miniature size and plasticity allow them to penetrate the crypts of the plasma membranes of infected cells. This localization provides mycoplasmas with mechanical protection from phagocytes. Therefore, mycoplasmas are either not phagocytosed at all, or phagocytosis is ineffective, including due to a lack of specific antibodies or complement.

8.8. Selection of pathological material for the diagnosis of mycoplasmosis in cattle, diagnosis and treatment

♦ blood concentrated with 6% EDTA (Trilon B), 1/20 by volume;

♦ blood serum;

♦ discharge and washings from the nasal cavity, conjunctiva, genitals, sperm, breast secretions;

♦ pieces of parenchymal organs, trachea, mucous membranes of the nasal cavity;

♦ synovial fluid of joints;

♦ fecal samples.

Samples are placed in a thermos with ice and delivered to the laboratory.

Based on data from the epizootic situation on the farm, a clinical study of the farm’s livestock, post-mortem examinations and laboratory studies:

1. Isolation of the pathogen on special serum media.

2. Detection of a specific antigen in pathological material using serological reactions (RDP, ELISA).

3. Detection of antibodies in the blood serum of sick animals (RSC, RNGA, ELISA).

Mycoplasmas are sensitive to antibiotics: dioxociline, monocycline, erythromycin, roxithromycin, azithromycin, etc. (Table 27).

You need to know that antibiotic therapy for mycoplasmosis leads to clinical well-being, but is not necessarily associated with the removal of the pathogen from the body, and often only contributes to the transition of the acute form of the disease to the latent one. Persistent mycoplasmas can become active again under the influence of factors that weaken the body’s immune status. In addition, mycoplasmas quickly acquire resistance to antibacterial agents.

Mycoplasmas are absolutely insensitive to cephalosporins, penicillin, ampicillin, rimfapin, polymyxin, glycopeptides, and sulfonamides.

8.9. Prevention

Table 27 - Minimum inhibitory concentrations of antibiotics effective against mycoplasmas.

To prevent the introduction of infection, it is necessary to comply with the entire range of organizational, economic, zoohygienic, and veterinary measures at the enterprise.

For specific prevention, a vaccine has been developed from the attenuated MA strain - VNIIVViM.

9. Immunocorrection for ARVI, chlamydia and bovine mycoplasmosis

When the body is infected with bovine ARVI pathogens, a protective role is played by specific and nonspecific humoral and cellular immunity factors associated with the participation of antibodies, macrophages, lymphocytes and leukocytes, and interferon. It should be taken into account that bovine ARVI often occurs with lifelong persistence of the pathogen with periodic exacerbations of the disease and remissions, and is a secondary immunodeficiency state.

Virus-neutralizing antibodies, whose activity is enhanced in the presence of complement, play a more important role in antiviral immunity and persist for a longer time than complement-binding antibodies. The mechanism of action of antibodies on infected cells is associated with inhibition of the release of the virus into the environment. In bovine ARVI, the formation of virus-antibody complexes is observed.

The pathogenetic role of immune complexes is associated with their possible participation in the development of immunopathological damaging changes in the body and with the influence on the functions of various effector cells. It is possible that in case of recurrent bovine ARVI, the ineffectiveness of serum antiviral antibodies is associated with the formation of similar infectious virus-antibody complexes. Antibodies can lyse infected cells in combination with complement T-lymphocytes and macrophages.

Thus, during ARVI in cattle, the synthesis of a wide range of antibodies, represented by IgM, IgG, IgA, IgE, is observed. The leading role in immunity is played by antibodies against the envelope antigens of the virus and membrane virus-specific antigens of infected cells.

In case of rota-coronavirus infection, it has been established that the presence of antibodies in the blood serum does not play a significant role in providing protection against infection. In newborn animals, antibodies obtained from milk play a protective role. Antibodies to rota-coronaviruses are detected in relatively high titers in colostrum immediately after birth, but their amount in milk quickly decreases within the first day, and after 4–6 days they are not detected at all.

The mechanism of immunity in chlamydia has not yet been fully revealed, however, there are features - post-infectious immunity is not developed. If infection occurs in the embryonic period, then after birth the calves lose the ability to produce antibodies against chlamydia. This is a special type of immunological reactivity - immunological tolerance, which is also observed in cattle VD.

With a long course of chlamydial infection, the immunogenic activity of the macroorganism is disrupted, which is expressed by a sharp decrease in the number of T-lymphocytes in blasts. Such disorders in the immune system lead to the development of immunodeficiency syndrome.

After contracting mycoplasmosis, animals acquire active immunity.

Mycoplasma infections are latent, or chronic infections; however, infected organisms typically exhibit symptoms of immunodeficiency. In the mammalian body, mycoplasmas, like other infectious agents, trigger specific and nonspecific immune reactions. The results of studies of the characteristics of the reaction of immunocompetent cells to mycoplasma infections indicate that the interaction of mycoplasmas with the immune system of mammals can lead to immunopathology associated with nonspecific stimulation or inhibition of immunocytes, as well as to autoimmune reactions as a result of a breakdown in tolerance to the host’s own antigens.

The characteristic morphological features of mycoplasmas, their miniature size and plasticity allow them to penetrate the crypts of the plasma membranes of infected cells. This localization provides mycoplasmas with mechanical protection from phagocytes. Therefore, mycoplasmas are either not phagocytosed at all, or phagocytosis is ineffective, including due to a lack of specific antibodies or complement

For the prevention and treatment of ARVI, chlamydia and bovine mycoplasmosis, immunocorrection plays an important role. Immunocorrection suggests the use of pharmacological agents to increase the functional activity of the immune system. It can increase or decrease the level of the immune response. Specific immunocorrection is limited to the action of one antigen, while nonspecific immunocorrection causes more general changes in the immune response.

Immunomodulators are divided into four groups - biological substances, drugs derived from microbes, synthetic and herbal.

Currently, the biological activity of the main thymus hormones, which stimulate the T-cell activity of the immune system, has been well studied. This group of drugs includes thymosin, thymopoietin, thymulin.

Opioid peptides synthesized by the pituitary gland (endorphins) and adrenal glands (encephalins) also have a stimulating effect on lymphocyte function. They maintain the level of the immune response by promoting T- and B-cell correction. Endophins and encephalins, together with andrenocorticotropic hormones, reduce the body's stress response.

Not only the antiviral, but also the immunomodulatory effect of interferon is well known. Interferon modulates the activity of cells of the immune system by activating macrophages and biostimulating T cells.

Mixoferon is a mixture of genetically engineered alpha interferons obtained by microbiological synthesis. The drug has high immunomodulatory and antiviral properties - priming interferonogenesis, activation of macophages and natural killer cells, imparting antiviral status to cells and viral replication.

Synthetic polynucleotides with antiviral and immunomodulatory properties include drugs such as immunofan, ribotan, ligaverin, polyxidonium, which are used according to the attached instructions.

Adaptogens are widely used in the practice of health-improving measures for acute respiratory infections in cattle. Adaptogens are a group of substances, mainly of plant origin, that increase the resistance of the animal body, stimulate the synthesis of a number of endogenous biostimulants that activate the immune system and have an antiviral effect (Erocond, Vivaton, Vidor, Vitadaptin, Germivit, Guvitan-S).

Interest in immunostimulating therapy has increased sharply in recent years and is associated primarily with solving problems of infectious pathology. Research in this area allows for a new approach to the selective modulation of certain links, and serves as a theoretical basis for the development of drugs with selective action.

Based on experimental data and results obtained from the use of the drugs Mixoferon, Erocond, Vivaton, Vidor, Vitadaptin Guvitan-S and the feed additive Germivit, schemes for their use were developed on farms in the Sverdlovsk Region, the Udmurt Republic, and the Komi Republic for preventive and therapeutic purposes.

Thus, active immunization of mother cows against bovine acute respiratory infections against the background of the introduction of the above-mentioned immunomodulators and feed additives promotes the accumulation of specific antibodies in colostrum and their subsequent transmission to their offspring, which prevents outbreaks of bovine acute respiratory infections among newborn calves. Immunocorrection of pregnant cows with these drugs reduces the number of complications during pregnancy and childbirth (stillbirth, abortion, endometritis) by 3.8–9.2 times, which serves as the basis for a possible increase in the efficiency of insemination of cattle with their help.

Treatment of young animals with immunomodulators in combination with the use of feed additives during weaning and transfer to groups prevents the negative consequences of stress.

Immunomodulators mixoferon, erocond, vivaton, vidor germivit, guvitan-S are harmless to animals, have a pronounced effect on stimulating specific immunity, increase the protective activity of vaccines, and feed additives - in addition - have a sedative effect on the central nervous system, weakening the negative effect stress factors on the body.

Drug Vidor– patent No. 2316329 dated 02/10/2008 “Method of preparing a drug for the prevention and treatment of diseases of viral etiology in cattle and a method of treating these diseases” (Travnik LLC under a license agreement with the Ural State Agricultural Academy, authors O.G. Petrova, Petrov A.E., Khamatov M.Kh.) – a preparation consisting of infusion and extract of medicinal herbs.

Vidor is characterized by high efficiency, breadth of immunopharmacological properties, and safety.

The fundamental difference from other immunotropic drugs is its high detoxifying activity; it is able to reduce the toxic properties of many compounds, including pharmacological drugs, that are dangerous to the animal’s body, and remove them from the body.

Studies have shown that Vidor is a true immunomodulator and normalizes both hypo- and hyperfunctions of the immune system.

The experience of clinical use of Vidor in more than 1000 heads of cattle indicates high clinical effectiveness and safety in the complex treatment of almost all immunodeficiency conditions of various origins that manifest themselves in cattle IRT.

Parenteral administration of Vidor in accordance with the schemes (see below) does not cause allergic reactions, does not have hepatonephrotoxic or toxic effects on the hematopoietic organs, and the drug is well tolerated by animals. According to general clinical and laboratory research methods, no side effects or complications were identified with the administration of the Vidora drug.

The use of Vidor in the complex therapy of animals with the genital form of bovine IRT is an effective way to reduce clinical manifestations in the acute phase, shorten the duration of relapses and noticeably reduce their frequency in the long-term period.

The use of the injection form of Vidor does not cause allergic reactions, side effects or complications. The drug does not have nephro- and hepatotoxic effects with this dosage regimen.

One of the nosological forms caused by the herpes virus in animals is respiratory, intestinal and genital herpes. Currently, these forms of infection are considered the most common diseases among other infections transmitted by airborne droplets and through artificial insemination. The peculiarity of bovine IRT is associated with asymptomatic virus carriage. There is evidence that 50 to 70% of newborn calves that develop neonatal herpes are born to mothers who are asymptomatic carriers.

Bovine RTI can cause reproductive dysfunction, abortions, and stillbirths.

Treatment of bovine IRT (genital form) has so far presented a certain difficulty, since:

2. herpes viruses persist for life in the axonoganglial structures of the central and peripheral nervous system.

The whole variety of methods for the treatment and prevention of bovine RTIs comes down to 3 main indicators: 1) immunoprophylaxis, 2) immunotherapy, 3) a combination of these methods.

The main target for the use of immunomodulatory drugs are secondary immunodeficiencies, manifested by frequent, recurrent, difficult-to-treat infectious and restorative processes of different localization. Such processes that require immunocorrection include recurrent herpesvirus infection, in particular its genital form.

Vidor, as an activator of the immune system, is used for the treatment and prevention of protective activity before vaccination in cases of bovine IRT, mastitis of herpes etiology, and enteritis caused by bovine IRT.

Perenteral administration of Vidor in combination with vaccine prophylaxis for bovine IRT is an effective way to reduce clinical relapses and noticeably reduce their frequency in a separate period.

Early administration of Vidor promotes faster re-epithelialization and a more pronounced prolongation of remission in cattle IRT.

In farms unaffected by bovine IRT, Vidor is administered subcutaneously to cows and calves at a dose of 0.025-0.03 cm 3 and 0.1-0.2 cm 3, respectively, per 1 kg of live weight before vaccination 24 hours before vaccination.

For the respiratory form of bovine IRT, sick calves are treated with Vidor at a dose of 0.1–0.2 cm 3 per 1 kg of live weight subcutaneously for 3–5 days once a day.

For the genital form of bovine IRT, cows are given Vidor subcutaneously at a dose of 0.025 ml per 1 kg of live weight and into the uterine cavity using a catheter syringe once a day, 20–25 cm 3 depending on the severity of the disease, for 3–5 days.

For mastitis, the drug is administered intramammary at a dose of 10.0 cm 3 twice a day with an interval of 48 hours for 3–7 days. In more severe cases of the disease, it is recommended to administer the drug not only to the affected quarter, but also to the remaining quarters of the udder, as well as subcutaneously, once a day, for 3–5 days, 10.0 cm 3.

To prevent the intestinal form of bovine IRT, newborn calves are given convalescent serum with Vidor orally - 20.0 cm 3 of Vidor is added to a bottle of serum of 200.0 cm 3 and administered at the dose indicated above. Vidor does not have a general or local adverse effect on the animal body. Store at temperatures between 4 and 15 °C.

Vitadaptin– a medicine based on raw materials of plant origin. As active ingredients, Vitadaptin contains carotenoids, ergosterol, vitamin E, linoleic, linolenic and arachidic acids of natural origin. It is used for the prevention and treatment of hypovitaminosis A, D, E, F, rickets, osteomalacia, toxic liver dystrophy, dermatitis, poorly healing wounds and ulcers, inflammatory processes, metabolic disorders, in order to improve immune status, stimulate reproductive function, animal growth and increasing the effectiveness of means of specific prevention of infectious diseases (ZAO “Pink Lotus”, Yekaterinburg).

For prophylactic purposes, Vitadaptin is administered intramuscularly once every three weeks, with therapeutic purposes once every seven days in doses: for breeding bulls - 10.0-15.0; cows – 10.0-15.0; calves 2.0–5.0 cm 3 / head.

In order to increase the effectiveness of specific ARVI prevention agents, the drug is injected 24 hours before the vaccine is administered.

Store Vitadaptin in its original packaging (100 cm3 dark glass bottles), in a dry place, protected from light, at a temperature of +5-25 °C.

Guvitan-S– a medicinal product based on sodium salts of humic acids of natural origin with high sorption capacity (Ariadna LLC, Yekaterinburg). Guvitan-S is used for therapeutic and prophylactic purposes for diseases of the gastrointestinal tract, metabolic disorders and to increase the resistance and productivity of animals.

The drug is administered orally in the form of an aqueous solution. In order to prevent gastrointestinal diseases and metabolic disorders, as well as to increase nonspecific resistance and productivity of animals, it is given at the rate of 0.5 ml/kg of animal weight 1–2 times a day for 20–30 days, after which a break is taken 15 days, then the cycle is repeated. For therapeutic purposes, an aqueous solution of Guvitan-S is used at a dose of 0.75 ml/kg of animal weight 2-3 times a day for 7-8 days. If necessary, the course of treatment is repeated.

The shelf life of the working solution of Guvitan-S in a tightly closed container at a temperature of +5 °C is 3 months, and packages with a dry preparation are 1 year.

Germivit– a high-energy feed additive (330 Kcal) of natural origin, manufactured using a unique patented technology, designed to enrich diets with nutrients (protein, fat) in order to increase the safety and productivity of farm animals and poultry (ZAO “Pink Lotus”, Yekaterinburg). It contains a complex of amino acids (17), vitamins (B 1, B 2, B 3, B 5, B 6, B 12, E (710 mg/kg), β-carotene), macroelements (calcium, phosphorus, sodium, magnesium , potassium), trace elements (manganese, iron, zinc, copper) and polyunsaturated fatty acids (11).

Addition rates (g/head/day): calves up to 2 months – 50–80, young cattle aged 2–6 months. – 80-150, over 6 months. and dairy herd - 150, dry and fresh cows - 150 and 250, respectively, sires - 300–400.

Vitadaptin, Guvitan-S and Germivit can be used individually to improve the health of the broodstock and obtain strong, viable offspring, but the most justified is the combined use of two veterinary drugs and a feed additive (Table 28).

Table 28 – Scheme for the use of Vitadaptin, Guvitan-S and Germivit on animals of the dead wood group

Observations and studies have shown that an integrated approach to solving the problem of improving the health of livestock of Sovkhoz Beregovoy LLC, Kaslinsky district, Chelyabinsk region from acute respiratory infections in cattle (subject to the use of Vidor and Vitadaptin in the scheme) increased the effectiveness of immunization against IRT, VD-BS, PG-3 (the average increase in antibody titer compared to conventional vaccination averaged 2.5–2.7 log 2). In addition, thanks to the use of feed additives Germivit, Guvitan-S and the veterinary drug Vitadaptin during the preparation of cows for calving, the levels of Ca, P, sugar, protein in the blood serum came into compliance with physiological standards, the functional activity of the liver was restored, and the concentration of immunoglobulins in the blood classes G, M, A increased by 22.5 on average; 33.33 and 23.80%, respectively, the ratio between T- and B-lymphocytes improved (on average by 23.4%), the live weight of calves at birth increased by 10.33%, while the incidence of postpartum complications decreased by 8.08 times, the average duration of the service period for the herd was established at 90.36 days (initially - 131.85 days), the milk productivity of cows during the milking period increased by 21.18% and the incidence of calves decreased by 85.70%. (digestive organs + respiratory organs) of the milk period.

As a result, the implementation of the entire complex of organizational, economic, technological and special measures made it possible to obtain an economic effect in the amount (data for 9 months of 2009) of 2.27 rubles per ruble of costs.

Preventive measures for acute respiratory viral diseases should begin with the creation of colostral immunity in newborn calves. The level of colostral antibodies depends on the time the calf received the first dose of colostrum and the amount of antibodies in the colostrum. With the intensive introduction of dairy farming, disturbances in the homeostasis of the cow's body undoubtedly lead to a decrease in the body's ability to produce antibodies.

The first numerous outbreaks of acute respiratory diseases, which caused significant damage to agricultural organizations in the Chelyabinsk region, were registered during the wintering period of 2003–2004. On 20 farms in 9 districts, 3,804 heads of cattle fell ill between November and April, including 1,208 cows. The death rate during the outbreak period in these farms amounted to 12 heads, of which 4 were cows. 237 heads of cattle were forced to be killed, including 55 cows. Infectious rhinotracheitis and parainfluenza type 3 were laboratory confirmed. Respiratory diseases were most widespread in the Chebarkul district (8 farms) and the Krasnoarmeysky district (4 farms). In 2003–2004, the Trivak vaccine was used in the region for the prevention of viral respiratory diseases (a polyvalent dry vaccine against infectious rhinotracheitis, viral diarrhea-disease of the mucous membranes, parainfluenza type 3, State Scientific Institution of All-Russian Research Institute of Virus named after Y.R. Kovalenko, Moscow). Since 2005, a number of farms in the Chelyabinsk region have been using the Kombovac series vaccines (inactivated, polyvalent vaccines against acute respiratory diseases of cattle (NPO Narvak, Moscow).

Despite the measures taken, respiratory diseases remain the main cause of economic losses in livestock farming in the Chelyabinsk region.

As a result of virological and serological studies on acute respiratory diseases of cattle, we studied the protective effect of some immunomodulators (Gumin-Eco, Vidor).

We were tasked with studying the effect of Gumin-Eco on the intensity of immunity to viruses of infectious rhinotracheitis, parainfluenza type 3 and on biochemical blood parameters in calves 10–28 days of age.

To study the effect of Gumin-Eco on the intensity of immunity to these viruses and the biochemical parameters of calves in 2 farms of the Chelyabinsk region, FSUE PKZ “Dubrovsky” and LLC “Beregovoy”, 2 groups of calves of 10 heads each (experimental and control) were taken from which blood from the jugular vein for serological and biochemical studies.

The calves of the experimental group were fed Gumin-Eco according to the instructions for its use 10–14 days before preventive vaccinations.

Humin-Eco is a complex preparation (Biohumus LLC, Yekaterinburg), consisting of free humic acids of at least 4.0 g/100 g, calcium of at least 180 mg/100 g, phosphorus of at least 25 mg/100 g , lysine not less than 20 mg/100 g, methionine not less than 30 mg/100 g. The drug combines all the positive properties of an immunomodulator. It increases the reactivity of immunocompetent cells due to the presence of humic acids. The drug was given to calves with water or milk at the rate of 0.2 g per kg of live weight once a day for a month. The studies were carried out in the regional veterinary laboratory of Chelyabinsk. The results are presented in table. 29.

Table 29 - Biochemical blood parameters in calves

The table data shows that Gumin-Eco has a beneficial effect on the biochemical parameters of the blood serum of calves. In the experimental group, compared to the control group, during the entire period of the experiment there was a significant decrease in the content of total protein, which can be explained by the normalization of protein metabolism in the calf’s body. During the period of the experiment, there was an increase in albumin content in the blood of calves in the experimental group, with a constant level of gamma globulins and a decrease in the level of alanine aminotransferase, which indicates normalization of liver function. The amount of glucose in the blood of the experimental calves increased significantly by the end of the experiment.

Serological studies of blood serum before the introduction of Gumin-Eco revealed titers of antibodies to infectious rhinotracheitis viruses, parainfluenza type 3 – 3.1±0.19 lg 2, 2.18±0.3 lg 2, respectively. After the administration of this drug, seroconversion to viruses to the above listed pathogens was noted in titers of 3.38 ± 0.27 lg 2, 4.68 ± 1.14 lg 2, which is higher by 4.03 ± 0.51 lg 2 compared to the control group, respectively (the difference is significant at P? 0.05).

Humin-Eco normalizes homeostasis, which has a beneficial effect on the development of immunity, forming a uniform and intense antiviral immunity during acute respiratory viral infections of cattle.

This infectious disease is considered one of the most dangerous and widespread in the Russian Federation. Mycoplasmosis of cattle and pigs is most often diagnosed, but the pathology can also affect birds. The peculiarity of the disease is that its causative agents are microorganisms that lack a cell wall. Because of this feature, mycoplasmosis is poorly treated with traditional antibiotics of previous generations, and therefore requires the use of the latest effective drugs. The lack of timely veterinary intervention is fraught with the development of many complications, leading farms to large economic losses. Mortality can be 10-15% of the total number of sick individuals.

Causes of animal mycoplasmosis

In nature, there are more than 10 types of mycoplasmas - microorganisms similar to bacteria, but differing in structure.

The main causes of the disease include:

• violation of hygiene in the place where animals are kept;
• dampness, high air humidity in the premises;
• decreased immunity of individuals due to poor microclimate and nutrition;
• purchasing an infected individual with hidden clinical manifestations of the disease into the herd (the incubation period of microorganisms reaches 27 days).

Infection occurs aerogenously - through breathing. Young individuals are especially sensitive. Most often, piglets between 3 and 10 weeks of age are affected. Mycoplasmosis in calves usually develops between 15 and 60 days of age.

Symptoms of mycoplasmosis

Among the common manifestations of pathology are:

• inflammation, pain in the knee and wrist joints with the formation of fistulas;
• lameness;
• redness of the eyes;
• apathy, lack of appetite;
• increase in body temperature to 40.1-40.5°C;
• sneezing, mucous discharge from the nose;
• cough, difficulty breathing (more often in piglets).

In adult cows, the disease affects the udder, so the milk becomes yellow, its consistency becomes uneven, and milk yield decreases.

Infection leads to numerous complications:

• in cows - mastitis, endometritis, vulvovaginitis, premature termination of pregnancy, birth of underdeveloped offspring;
• in calves - arthritis, pneumonia, meningitis, rhinitis, conjunctivitis;
• in bulls - epididymitis, orchitis;
• in pigs - pneumonia, respiratory diseases.

If left untreated, cows may develop infertility. Piglets with respiratory complications may die from suffocation.

Diagnostics

Diagnosis is made on the basis of external examination, clinical manifestations and laboratory tests of tissues, secretions, aborted or stillborn fetuses. In the laboratory, the PCR method is used to detect the pathogen.

Treatment of mycoplasmosis

The only effective treatment is the use of antibiotics. For mycoplasmosis, drugs of the latest generation are used, since the microorganisms that cause mycoplasmosis develop resistance to traditional antibiotics.

The NITA-FARM company proposes to use a drug for mycoplasmosis - an antibiotic of the latest generation of fluoroquinolones.

• It is based on levofloxacin, a substance belonging to the third generation fluoroquinolones.
• Treatment of a wide range of infections that are resistant to previous generation antibiotics.
• The bioavailability of the drug is 99%.
• Within 2 hours after use it reaches maximum effectiveness, penetrating well into the tissue.
• 100% effectiveness within 24-48 hours.
• Equally effective in the treatment of mycoplasmosis in pigs and cattle.
• One daily injection is enough for a 3-5 day course.
• Within 2 days it is completely eliminated from the body, mainly in the urine.
• Already 48 hours after using the drug, milk can be used for food purposes.

The effectiveness is confirmed by clinical studies and relevant documents. You can order Lexoflon directly from NITA-FARM.

Prevention

Veterinarians and farm workers should follow the following recommendations:

• maintain cleanliness in areas where animals are kept;
• feed calves with milk tested for the absence of mycoplasmas;
• pay special attention to cases of mastitis, rhinitis and check the animal for infection;
• take care of a nutritious diet to improve immunity;
• Avoid stress factors such as increased humidity and temperature changes.

Bovine mycoplasmosis is a contagious disease caused by mycoplasmas, microorganisms whose structure does not fit the description of viruses or bacteria. This disease is characterized by damage to the respiratory system, the development of pneumonia, keratoconjunctivitis, arthritis, endometritis, and mastitis. The disease causes significant economic damage to the farm in which it is registered, in the form of loss of livestock, loss of live weight and costs of treatment and preventive measures. It is important to understand what are the reasons for the development of mycoplasmosis, how it manifests itself in cows, and how it is treated.

Causes

Infection with mycoplasmosis occurs in different ways - nutritional, airborne or intrauterine. Both adults and young animals can get sick. Sick animals or carriers of the pathogen release it into the external environment with saliva, urine, mucus from the nose, milk, and feces. The source of infection may be food, bedding, or equipment. Often the carriers of pathogens are small rodents and insects.

Outbreaks of mycoplasmosis occur more often in the fall and winter when cows are kept in stalls. Favorable conditions for infection are:

1. Overcrowding of animals.
2. Dampness.
3. Poor diet, which leads to a decrease in the resistance of the cows’ body.

Attention! To protect your farm from mycoplasma infection, it is important to quarantine all newly arrived animals on the farm for 30 days.

Symptoms

Mycoplasmas affect different systems of the animal body, so the symptoms for different forms of the disease differ. Most often, the pathogen affects the respiratory system. In this case, we are talking about respiratory mycoplasmosis. The symptoms of the disease are as follows:

1. General oppression.
2. Loss of appetite.
3. Sneezing, discharge from the nose, first of a transparent mucous secretion, and later of a purulent one.
4. A dry cough that becomes wet over time.
5. Rapid breathing.
6. Wheezing.

If treatment is not started, the animal's condition gradually worsens. In the future, the development of polyarthritis is possible. The joints become inflamed, hot, and painful. Sick animals lame. Cows often develop mastitis. Mycoplasmosis can be complicated by a bacterial infection, then the disease occurs in an even more acute form and often ends in death.

In some calves, mycoplasmosis manifests itself as inflammation of the conjunctiva and cornea of ​​the eyes. In this case, the symptoms of the disease are as follows:

1. Fear of light.
2. Anxiety.
3. Tearing.
4. Redness of the cornea of ​​the eyes, the appearance of gray and cloudy spots on it.

Attention! When inflammation from the conjunctival sac spreads to the cornea, keratitis develops, and photophobia manifests itself even more acutely. As a result of the development of keratitis, blindness can occur.

Diagnostics

Diagnosis requires an integrated approach. When making a diagnosis, it is necessary to exclude infectious rhinotracheitis, adenoviral infection, as well as brucellosis, pasteurellosis, leptospirosis, and chlamydia.

When making a diagnosis, not only the clinical signs of the disease are taken into account, but also the results of a pathological autopsy of animal corpses, as well as the results of laboratory testing of biomaterial. For analysis, material is taken from individuals who died from the disease and did not receive treatment. It is important to collect samples for research no later than 3-4 hours after death. Fragments of internal organs - liver, brain, spleen, as well as joints of dead cows - are used as biomaterial.

As material for testing for mycoplasmosis, blood plasma, milk (for signs of mastitis), and nasal discharge are taken from living individuals. Using various methods, the presence of the pathogen is detected in samples taken for analysis. The diagnosis is considered confirmed if the titers of antibodies to mycoplasma in the blood serum increase more than 4 times.

Treatment

There is no specific treatment regimen against mycoplasmosis. Therapy is carried out comprehensively and includes the use of:

1. Antibiotics.
2. Expectorant drugs.
3. Vitamins.
4. Immunostimulants.

Attention! Diet is an essential part of treatment.

Antibiotics for cattle against mycoplasmosis are used intramuscularly or orally. In the event of the spread of respiratory mycoplasmosis in a herd, it is advisable to use them in the form of aerosols for a whole group of sick animals. List of drugs used to combat mycoplasma:

• Levomycetin;
• Enroflon;
• Tetracycline;
• Tetravet;
• Biomutin;
• Tiamulin;
• Dibiomycin;
• Terravitin.

Reference. The course of antibiotic treatment is continued for up to 7 days. The dosage is prescribed by the veterinarian.

An approximate treatment regimen for a group of calves infected with mycoplasmosis looks like this. Terravitin 500 is given orally at a dosage of 20-40 mg/kg in the morning and evening. At the same time, Trimerazin is given orally twice a day (dosage - 1 mg for every 15 kg of weight). The long-acting drug Biovit is given with food once a day, 3-5 g to each calf. Along with these medications, it is necessary to include ascorbic acid in the treatment regimen at a rate of 1 g per day.

Norsulfazole solution is administered intravenously. It is prepared like this:

1. 600 ml distilled water.
2. Glucose solution at a concentration of 40% - 300 ml.
3. Rectified alcohol 96% - 300 ml.
4. Norsulfazole in powder form – 40 g.

The prepared solution is administered once a day to each sick individual into a vein, 50 or 60 ml for 3 days. The next 4 days use a different solution for intravenous injection. It is administered to sick calves once a day, and is prepared from the following components:

1. Calcium chloride in the form of a solution at a concentration of 10% - 15 ml.
2. Glucose solution 40% - 25 ml.
3. Hexamethylenetetraamine solution 40% - 10 ml.
4. The fourth component is a solution of caffeine sodium benzoate (20%) - up to 3 ml.

To stimulate the discharge of sputum from the upper respiratory tract, animals are given mucolytics and expectorants to drink. To strengthen the body's resistance, the treatment regimen for mycoplasmosis includes B vitamins (mainly B12), as well as globulins or plant immunostimulants, for example, Eleutherococcus.

Important! To improve intestinal function and restore microflora, it is advisable to give cows probiotics.

Prevention

To protect your livestock from mycoplasmosis, you must strictly adhere to the following rules:

1. Never import animals to form a herd from farms considered unaffected by mycoplasmosis. Do not accept inventory items from them.
2. When accepting cows to the farm, keep them in quarantine for one month, carefully examine newly arrived individuals for signs of disease development, paying special attention to the respiratory system.
3. It is important to treat barns against insects that can carry the causative agent of mycoplasmosis.
4. If rodents are found in premises where livestock are kept, it is necessary to carry out deratization.

If a case of mycoplasmosis infection is registered on the farm, sick cows are separated into an isolation ward and treatment is started immediately. All individuals that have been in contact with infected cows are treated with antibacterial agents. Premises, equipment, bedding, feeders and drinking bowls are disinfected.

Attention! Milk from animals that have tested positive for mycoplasmosis requires heat treatment.

Bovine mycoplasmosis is a dangerous infectious disease, but it can be controlled. Treatment of this disease is most effective at the initial stage, so it is important to constantly monitor the health of animals on the farm. If signs of mycoplasmosis are detected in a cow, you need to report this fact to the veterinary service. The farm will be quarantined. It will be removed 2 months after the last animal has recovered and final disinfection has been carried out.

Bovine mycoplasmosis is one of the most common diseases in the world, affecting both adult cows and calves, including newborn young animals.

Bovine mycoplasmosis manifests itself in the form of conjunctivitis (inflammation of the mucous membrane of the eyes), joint disease (arthritis), various respiratory diseases, spontaneous abortion and the birth of still calves, as well as mastitis and endometritis. Calves are especially seriously ill: they lose their appetite, become lethargic, then they develop purulent discharge from the respiratory tract and inflamed joints. Calves are infected from the first days of life. In cows, the udder is more often affected: the milk becomes yellow and heterogeneous, and milk yield drops sharply. The animal's temperature rises.

The cause of the development of all these dangerous ailments are microorganisms that are similar to both bacteria and viruses, but at the same time have their own characteristic signs and properties.

So, for example, mycoplasmas are not afraid of severe frosts, but die in the sun within 5 hours. When dried, they remain viable for five years, and in rotting remains they are active for almost two weeks. At the same time, mycoplasmas “do not like” cleanliness and disinfectants. Routine cleaning and treatment with bleach in barns and calf barns is an excellent prevention of the development of this disease, which is dangerous for cattle.

A characteristic feature of mycoplasmosis in cattle is its localization: animals of the same farm are affected. At the same time, bovine mycoplasmosis has been diagnosed for decades.

Infection occurs through contact with sick animals. In this case, the causative agent of the disease can be carried by insects: flies and mosquitoes.
The incubation period lasts from 7 to 27 days. For this reason, all new animals taken from other farms must undergo quarantine, including sanitary treatment and separate housing for a month. The rule is simple: bovine mycoplasmosis is much easier to prevent than to treat.

When treating mycoplasmosis in calves and cows, it is important to correctly diagnose and exclude diseases with similar symptoms. For this purpose, laboratory tests are mandatory.

There are no effective drugs developed specifically for the treatment of mycoplasmosis in cows. Sick animals should be treated comprehensively, using antibiotics and only under constant medical supervision.

Enzootic pneumonia is caused by the bacterium Mycoplasma hyopneumoniae. It is widespread in swine populations and is present endemically in most herds around the world. It is transmitted either through contact between sick and healthy pigs, or by air over a distance of up to 2.5-3 km, if climatic conditions permit.

The bacterium quickly dies in the external environment, especially when dried. In humid conditions it lasts for two to three days. The incubation period ranges from two to eight weeks. Under good conditions and management, the course of the disease without complications does not pose a threat to the body.

However, mycoplasmosis can have more serious consequences in the presence of diseases such as actinobacillus pleuropneumonia (APP), pasteurellosis, hemophilosis, PRRS or influenza. Mycoplasmosis always affects the apical and cardiac lobes, sometimes the accessory or middle part of the diaphragmatic lobe, causing an increase in the density of the lung tissue up to the soft tissue and liver.

If more than 15% of the lungs are affected, then it is very likely that mycoplasmosis is present in the population. In herds free from M. hyopneumoniae, the number of affected lungs ranges from 1 to 2% and the volume of compacted tissue is very small.

If mycoplasmosis is absent, then the effects caused by other pathogenic microorganisms are greatly reduced. Therefore, it is believed that M. hyopneumoniae opens the gates of infection for other diseases.

Clinical symptoms

Acute form

The acute form can usually be observed when M. hyopneumoniae is first introduced into a herd. Between six and eight weeks after infection, severe acute pneumonia, cough, respiratory failure, fever, and high mortality occur in all age groups. This clinical form is extremely rare and is often complicated by other pathogens.

Chronic form

Under normal conditions, the pathogen can persist in the herd for a long period. Maternal antibodies are passed through colostrum to the piglets and they develop colostral immunity, which lasts from seven to twelve weeks, after which clinical symptoms begin to appear. The disease is accompanied by a long, incessant cough, some animals have difficulty breathing and signs of pneumonia appear.

Diagnostics

In most cases, the diagnosis is based on the clinical picture and post-mortem diagnosis of the lungs in pigs.

For laboratory confirmation, one or more studies are carried out: ELISA test, histological examination of stained lung preparations, complement fixation reaction, polymerase chain reaction, enzyme immunoassay or isolation of a pure culture of the pathogen.

Slight compaction of the anterior lobes of the lungs can be caused by other pathogens, such as influenza, PRRS, hemophilia, some viruses or other mycoplasmas.

Treatment

In disadvantaged farms, treatment should be based on the following principles:

• separate keeping of animals aged from 10 to 20 weeks;
• antibiotic therapy (lincomycin, tetracycline, tiamulin, tylosin);
• culling of seriously ill animals;
• symptomatic therapy.

Antibiotics only prevent the development of clinical signs, but do not free the animal’s body from the pathogen.

Prevention and management

The basis for the prevention and recovery of mycoplasmosis is vaccination of piglets.

For mycoplasmosis-free farms

The main place in disease prevention is given to veterinary, sanitary and zoohygienic measures. Pigs for farm stocking should be purchased only from safe farms, quarantined after import and carefully examined to identify mycoplasma carriers.

It is necessary to create optimal housing and feeding conditions, observe pig breeding cycles, stocking density standards, and carry out technological sanitary breaks when housing animals.

The increase in incidence is associated with:

• excessive density of animals in pens and premises;
• temperature changes and drafts;
• hypothermia;
• high environmental humidity;
• high levels of carbon dioxide and ammonia indoors;
• poor sanitation;
• high dust content in the air;
• moving and mixing pigs, stress;
• lack of feeding places;
• poor quality or inadequate feeding;
• sudden change in diet;
• less than 3 cubic meters of air space and 0.7 square meters. metro area on the head;
• lack of air circulation in the room;
• the presence of diseases such as PRRS, Aujeszky's disease, APP, influenza.

To control mycoplasmosis and respiratory diseases in disadvantaged farms:

• vaccination;
• optimization of the number of animals in pens and premises;
• strict control over sanitation and hygiene in the premises;
• control of dust in premises, optimization of feed grinding to reduce it;
• ventilation optimization;
• do not allow mixing and simultaneous keeping of pigs of different age groups;
• strict adherence to the “empty-occupied” technology and implementation of a technological gap.