Quantitative determination of retrovirus-specific immune complexes

The article presents the results of studying the dynamics of the formation of antibodies and immune complexes, reveals the prospects for improving the early diagnosis of cattle leukaemia. Studies were conducted for 6 months on an experimental group of animals consisting of 12 cows. The titers of free and bound antibodies in blood serum and milk were determined by enzyme-linked immunosorbent assay. The results of studies showing that changes in titers of anti-leukaemia antibodies in the blood serum of cows naturally infected with BLV (bovine leukaemia virus) are significantly different from experimental infection data are adduced. In cows infected with BLV, there is no definite relationship between antibody titers in milk and in blood serum. With sufficiently high titers of serum antibodies, antibody titers in milk can be minimal for the same cows; conversely, with low titers of serum antibodies, there can be high antibody titers in milk. In the titers of antibodies free and bound in the immune complexes in blood serum with the development of the disease, a certain dependence is traced. With a decrease in titers of free antibodies, in most cases, an increase in titers of “bound” antibodies is observed, i.e., the degree of formation of circulating immune complexes (CECs) increases. There is no clearly defined dependence in the dynamics of changes in titers free and bound in immune complexes of antibodies in milk samples. They can remain at the same level for a long time, both at low and rather high levels.

Section: Introductionmentioning

confidence: 99%

Features of humoral immunity in cows infected with the leukaemia virus

Yakupov

Valiev

Zinnatov

et al. 2020

“…In this context, the development of new ef icient adapt genic agents with poly functional properties, providing the body resistance to radiation and to numerous unfavorable environmental factors, remain relevant. In this context, creating biopharmaceuticals based on naturally biological active substances is considered prospective (Schetters et al, 1990).…”

Section: Introductionmentioning

confidence: 99%

Study of radioprotective properties of chitosan at gamma-irradiation

Фролова

Gryn

Kovaleva

et al. 2020

The objective of this study was the analysis of adaptogenic effects of chitosan at gamma-irradiation. The study of radioprotective properties of chitosan was carried out on male mice having the weight of 20-25 g, exposed to gamma-irradiation at the doses of up to 800 bar at the Gamma Panorama unit (radiation source – Cs137, gamma dose rate – 14 R/min, duration of irradiation – 58.5 min). 4 experimental and 2 control groups with 7 animals in each have been formed. The medicine dose schedule, allowing to identify both the prophylactic effect and the therapeutic effect of chitosan, was used in the experiment. It was found out in experiments on white mice, with the purpose of determining 50% lethal dose (LD50) that chitosan belongs to the substances of hazard class 4 because its LD50 considerably exceeds 5000 mg/kg; at this, the toxicity of chitosan decreases parallel to its molecular weight decrease. The prophylactic and therapeutic effect of low-molecular chitosan (molecular weight 5-10 kDa) as abdominal injection at the doses of 200 mg/kg of body weight. It has been demonstrated that the mice from the experimental group I that received chitosan 3 days before the irradiation remained alive throughout the entire observation period (30 days). In the animals of II, III, IV experimental groups that received chitosan in 3, 9 and 22 days after the irradiation, the survival rate by the experiment end was 86, 43 and 29%, respectively, with the 100% death of animals in the control group I (irradiated animals without the use of chitosan) and full safety of animals in the control group II (non-irradiated animals).

“…Today, the entire territory of the republic is endemic for this disease (Yakobson et al, 1998). The presence of a large number of anthrax cattle burial grounds, including those not established (Schetters et al, 1990), as well as permanently dysfunctional sites, their high density and speci ic gravity, create constantly persisting high risks in the republic of a possible aggravation of the situation (Jaworski et al, 2016). The existing system for the preven-tion of anthrax is not capable of completely eliminating it, since there are currently no effective and harmless methods of sanitizing the soil foci of infection, and the question of the appropriateness of their use remains open.…”

Section: Introductionmentioning

confidence: 99%

Analysis of the epizootic situation and improvement of the scheme for the specific prevention of anthrax

Ivanova

Melnikova

Rodionov

et al. 2020

The article shows the epizootic situation for three periods (decades): from 1990 to 1999, from 2000 to 2009 and from 2010 to 2019. As a result of the studies, it has been established that since 1990, the 26 sporadic outbreaks of anthrax have occurred in the territory of the republic, 13 of them in territories where the disease was not previously recorded, which indicates the spread of the pathogen in the environment. Due to the special situation of anthrax, which consists of a large number of unidentified anthrax cattle burial grounds, as well as high density and activity of dysfunctional sites, the republican veterinary service recommended vaccinating an adult cattle population twice a year with an interval of 6 months: in spring and autumn, to create the maximum percentage of immune animals. In addition, a method has been introduced in the republic for assessing specific prophylaxis of anthrax, based on the detection of specific antibodies in the blood serum of an immunized livestock by an indirect hemagglutination test. This method allows the detection of animals that were skipped during vaccination and tolerant animals. Thanks to the joint work of veterinarians and scientists who improved the specific scheme for the prevention of anthrax, the republic managed to reduce the number of outbreaks of infection by 15 times, which allows us to predict further improvement in the epizootic situation for this infection.