Influence on Mycotox® NG effects on relative weights of some internal organs in Pekin ducks with experimentally reproduced aflatoxicosis В1

Contamination of poultry feeds with mycotoxins is a global problem faced by poultry industry due to increased demands and availability of poor-quality cereals. The aim of the present study was to evaluate the beneficial effects of a mycotoxin binder (Mycotox NG) on relative weights of internal organs in Pekin ducks with experimental aflatoxicosis. The birds were divided into one control and six experimental groups (n=10) as follows: group І (0 mg/kg AFB1 without Mycotox NG); group ІI (0.5 g/kg Mycotox NG); group ІІI (1.0 g/kg Mycotox NG); group IV (0.2 mg/kg AFB1); group V (0.4 mg/kg AFB1); group VI (0.2 mg/kg AFB1 + 0.5 g/kg Mycotox NG) and group VII (0.4 mg/kg AFB1 + 1.0 g/kg Mycotox NG). Trial duration was 42 days. It was established that ducks fed AFB1-contaminated feed had increased relative weights of liver, kidneys, pancreas, heart, gizzard and proventriculus compared to the control group. At the same time, the relative weights of immunocompetent organs (thymus, spleen and bursa of Fabricius) were reduced. The addition of Mycotox NG to the feed contaminated with AFB1 compensated partly the changes in relative weights of visceral organs. The results from the present study demonstrated that the tested toxin binder could be effective for reduction of toxic effects of aflatoxins in domestic ducks.

Composition of peripheral blood leukocytes and immunocompetent organs of white char in the lake Kronotskoye

The composition of leukocytes reflects the species features of fish. The ratio of individual cell types reflects the functional state of the organism and the nature of the influence of biotic and abiotic stress factors. Kronotskoye Lake is located in the Far East on the territory of the Kronotsky State Natural Biosphere Reserve (Kamchatka). Due to the peculiarities of the hydrological regime and the relief of the Kronotskaya River basin, anadromous migration along it is limited. Therefore, anadromous fish do not return to the lake after the marine period of their life cycle. The lake basin is inhabited by at least six reproductively isolated forms (species) of chars. White char, Salvelinus albus Glubokovsky, 1977, at the early stages of ontogenesis feeds on invertebrates, and as it grows up, it goes on to a predatory lifestyle. White char migrates around the lake: spawning occurs in the tributaries, and feeding takes place in the lake itself. This work is devoted to the study of the intensity of leukopoiesis and leukocyte composition of the blood, head kidney and spleen of the white char of Lake Kronotskoye. Seven individuals caught using gill nets from July 8 to August 14, 2011 were studied. Peripheral blood was sampled from the tail vein. Sampling also included spleen and head kidney tissues, blood smears and organ-imprinted smears of kidney and spleen. The leukocyte formula and the frequency of occurrence of leukocytes in a peripheral blood smears were calculated using light microscope. The composition of white blood cells in the white char is similar to that of other fish species (lymphocytes, monocytes, neutrophils, and blast cell forms). No basophils or eosinophils were found. In organ-imprinted smears of immunocompetent organs (kidney, spleen), the percentage of lymphocytes is lower and the percentage of blast forms is higher than in the blood leukogram. The abundance index differed from the data obtained in the study of other fish species. English version of the article is available at URL: https://panor.ru/articles/composition-of-peripheral-blood-leukocytes-and-immunocompetent-organs-of-the-white-char-of-lake-kronotskoye-kamchatka/68317.html

Possibilities of intestinal dysfunction treatment in period of convalescence of COVID-19

The article presents a clinical example of the treatment of persistent intestinal dysfunction in a patient with a relapse and in the period of COVID-19 convalescence. Differential approaches to the clinical and laboratory diagnosis of gastrointestinal disorders in patients with COVID-19 or SARS-CoV-2 infection and with a high risk of pseudomembranous colitis are considered. The role of bacteriophages in restoring the normal function of the gastrointestinal tract is considered. The total duration of treatment of a patient with a gastrointestinal disorder on the background of relapse and subsequent convalescence of COVID-19 from the moment of treatment was 8 weeks with the active use of anti-inflammatory, sorbing, anticoagulant, antiviral and antibacterial therapy. A significant contribution to the process of clinical improvement was made by the use of intestinal bacteriophage, reducing the risk of pseudomembranous colitis.Conclusions. COVID-19 is a disease characterized by a multisystem lesion and long-term consequences for immunocompetent organs, including the gastrointestinal tract. This fact forces us to reconsider some aspects of traditional therapy for intestinal dysfunction and provides opportunities for new, less aggressive treatments.

Human immunocompetent Organ-on-Chip platforms allow safety profiling of tumor-targeted T-cell bispecific antibodies

Traditional drug safety assessment often fails to predict complications in humans, especially when the drug targets the immune system. Here, we show the unprecedented capability of two human Organs-on-Chips to evaluate the safety profile of T-cell bispecific antibodies (TCBs) targeting tumor antigens. Although promising for cancer immunotherapy, TCBs are associated with an on-target, off-tumor risk due to low levels of expression of tumor antigens in healthy tissues. We leveraged in vivo target expression and toxicity data of TCBs targeting folate receptor 1 (FOLR1) or carcinoembryonic antigen (CEA) to design and validate human immunocompetent Organs-on-Chips safety platforms. We discovered that the Lung-Chip and Intestine-Chip could reproduce and predict target-dependent TCB safety liabilities, based on sensitivity to key determinants thereof, such as target expression and antibody affinity. These novel tools broaden the research options available for mechanistic understandings of engineered therapeutic antibodies and assessing safety in tissues susceptible to adverse events.

Human immunocompetent Organ-on-Chip platforms allow safety profiling of tumor-targeted T-cell bispecific antibodies

Traditional drug safety assessment often fails to predict complications in humans, especially when the drug targets the immune system. Here, we show the unprecedented capability of two Organs-on-Chips to evaluate the safety profile of T-cell bispecific antibodies (TCBs) targeting tumor antigens. Although promising for cancer immunotherapy, TCBs are associated with an on-target, off-tumor risk due to low levels of expression of tumor antigens in healthy tissues. We leveraged in vivo target expression and toxicity data of TCBs targeting folate receptor 1 (FOLR1) or carcinoembryonic antigen (CEA) to design and validate human immunocompetent Organs-on-Chips safety platforms. We discovered that the Lung-Chip and Intestine-Chip could reproduce and predict target-dependent TCB safety liabilities, based on sensitivity to key determinants thereof, such as target expression and antibody affinity. These novel tools broaden the research options available for mechanistic understandings of engineered therapeutic antibodies and assessing safety in tissues susceptible to adverse events.

Composition of peripheral blood leukocytes and immuno-competent bodies of the cross carp “Petrovsky” in different periods of the fishing season

Crossing is an effective method of increasing agricultural production. In addition to the productive qualities of the resulting crosses, it is important to maintain and enhance their immune resistance. Breeding for immunity to pathogens of various diseases provides a decrease in economic losses and an increase in breeding efficiency. Cross “Petrovsky” (breeding achievement No. 9153820) is a reciprocal hybrid of Anish Mirror and Chuvash scaled productive carp species. It has been established that this cross is superior to the parental forms in terms of growth intensity and survival of juveniles. The work is devoted to a comparative analysis of the leukocyte composition of peripheral blood and immunocompetent organs of the carp cross “Petrovsky” in different periods of the fish-breeding season. The studies were carried out in late May and early October 2019 in the Kirya breeding farm, Chuvashia (2nd fish breeding zone). In fish, peripheral blood was sampled from the tail vein and tissues of the spleen and head kidney. Blood smears and organ-imprinted smears were taken for the study. The preparations were examined under a light microscope and the leukocyte formula was determined. The study of leukograms of immunocompetent organs and tissues of fish helps to judge the functional state and immune resistance of fish. To determine the index of the abundance of leukocytes in a peripheral blood smear, 100 visual fields were examined in different areas. This indicator allows you to record the intensity of leukopoiesis and indirectly assess the level of leukocytes in a unit of blood volume. Studies have established differences in the proportion of certain types of leukocytes and the intensity of leukopoiesis in different periods of the fish-breeding season. Fish tissues and organs differed in the proportion of lymphocytes, monocytes, and neutrophils. The obtained data can be used in carrying out selection and breeding work aimed at increasing productivity and enhancing the resistance of fish to infectious diseases.

EVALUATION OF THE IMMUNOCORRECTIVE EFFECT OF VESELKA ON CHANGES IN IMMUNOCOMPETENT ORGANS OF ANIMALS

The immunocorrective properties of the basidial fungus Phallus impudicus were evaluated in order to further use the drug in various dosage forms for batch control according to the indicator "Biological activity" in the conditions of control services laboratories.

Veterinary sanitary assessment of the quality of meat products and the morphofunctional characteristics of the muscle tissue of pigs fed a mineral adaptogen

Pigs are the most susceptible to stress. Therefore, the purpose of our research was to assess the effect of the mineral adaptogen on animal health and the quality of meat products. Research methods. The studies were conducted on piglets of a large white breed. With the use of hematological, immuno-biochemical, morphological methods of research and veterinary and sanitary assessment of the quality of meat products obtained. Results. It was found that the mineral adaptogen has a positive effect on the immune system, metabolic processes, and the reduction of stress-dependent glucose and cortisol levels. Scientific novelty. For the first time, comprehensive studies have been conducted showing the effect of mineral adaptogen not only on immunocompetent organs and immune indicators, but also a complex effect on stress resistance, reduction of toxigenic activity of feed, stabilization of metabolic processes in animals, and veterinary-sanitary and micromorphological assessment of the quality of meat products.

Effect of β-mannanase enzyme supplementation on the morphofunctional state of broiler chickens’ immunocompetent organs

Identifying and eliminating factors that interfere with the nutrient absorption from feed is essential for successful poultry rearing. The nutritional value of feed mixtures used in the poultry industry can be increased by the use of enzyme supplements, in particular β-mannanase (Hemicell), which breaks down the anti-nutrients β-mannans that are present in significant quantities in soy products. For the study, two groups of 50 broiler chickens were formed. In the control group a standard feed mixture from cereals was used, particularly soybeans, and in the experimental group 0.05% β-mannanase enzyme supplement (Hemicell) in addition to the compound feed was used. Production indicators were established (average daily gain, survival rate, feed costs). On the 15th, 25th and 42nd days of rearing, lymphatic organs (cloacal bursa and spleen) were collected from seven chickens of each group, followed by macro, microscopic and morphometric evaluation. It was found that the addition of an enzyme supplement promotes an increase in the production indicators of poultry rearing, reduces feed use, does not affect the macroscopic characteristics of the lymphatic organs. β-mannanase (Hemicell) contributes to the maintenance of an active morphofunctional state of the cloacal bursa and spleen during the entire period of poultry rearing. This was manifested by high indices of the absolute and relative organ masses, a moderate development degree of tissue components and cloacal bursa histological structures (number, shape and average length of lymphatic nodules, density of lymphocytes in the cortex and medulla) and spleen (number and diameter of lymphatic nodules and periarterioal lymphatic sheaths). In the control group, at all stages of rearing, the morphofunctional state of the bursa was found to be lower and signs of immunosuppression were revealed by the end of the rearing period (a sharp decline in the bursa absolute mass, organ mass index, a decrease in the average length of nodules, change in their shape, thinned cortical layer and delymphotisation). The morphofunctional state of the spleen of chickens from the control group remained high throughout the entire study period. So use of the β-mannanase enzyme supplement (Hemicell) while rearing broiler chickens not only increased the efficiency of their rearing but also contributed to maintaining a high morphological and functional state of the cloacal bursa.

Pathomorphology of certain organs of immunogenesis by experimental reproduction of coronavirus infection in dogs

The article, based on the results of histological studies, presents data on the microscopic structure of the immune system – thymus, spleen, lymph nodes of dogs with experimental infection with coronavirus enteritis. Pathomorphological studies of immunocompetent organs from the dead (n = 5) puppies crossed Labrador breeds with outbred, infected with a coronavirus field isolate cultured on heterologous cell cultures (kidney kidney hamster (BHK-21), rabbit kidney (RK-13) and the renal mumps (SPEV). Pathological dissection of dogs was performed by partial evisceration in the usual sequence. Prepared histological sections were stained with hematoxylin and eosin according to standard recipes. The general histological structure and microstructural changes of histo- and cytostructures of organs in histological samples were studied under a light microscope. During coronavirus enteritis in dogs, pathomorphological changes in immunocompetent organs were found, which characterize the suppression of immunogenesis function during an infectious disease of viral etiology. Thus, in the spleen there are spotted hemorrhages, lymph nodes, moderate hyperplasia, with signs of hemorrhagic inflammation. Active proliferation of lymphoid cells, which leads to hyperplasia, is one of the markers of the pathogen's effect on the macroorganism in the form of an inflammatory process in regional lymph nodes, which indicates the multiplication of the virus and the development of immunological processes. Based on our analysis of literature sources, monitoring results and our own research, it was found that viral enteritis occupies a leading place in the infectious pathology of dogs and causes significant harm to animal owners. Thus, the need for additional research to clarify, supplement and summarize data on the pathomorphology of various organs and tissues in canine corona viridae enteritis, current immunoprophylaxis and treatment can significantly reduce the incidence and mortality from infection. We found a set of histological changes in the immune system during the experimental reproduction of coronavirus infection, can be considered a characteristic criterion for pathomorphological differential diagnosis of coronavirus enteritis in dogs.