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16«©oyyomum-jmtmail» mm / veterinary sciences
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Lvivskoho natsionalnoho universytetu veterynarnoi medytsyny ta biotekhnolohii im. S. Z. Gzhytskoho, 16(3), 335-339. URL:
http://nbuv.gov.ua/UJRN/nvlnu_2014_16_3%281%29__4 8 (in Ukrainian).
21. Varkholiak, I. S., Gutyj, B. V., Leskiv, Kh. Ya., Kushnir, V. I., Hariv, I. I., Martyshuk, T. V., &
Guta, Z. A. (2021). The effect of bendamine on antioxidant protection of rats' myocardium in doxorubicin intoxication. Colloquium-journal, 7(94), 18-21. doi: 10.24412/2520-6990-2021-794-18-21.
22. Vlizlo, V. V. (2012). Laboratorni metody* doslidzhen u biologiyi, tvary'nny'cztvi ta vet-ery'narnij medy'cy'ni: dovidnyk. L'viv: Spolom (in Ukrainian).
Said W.S.1, Gytyj B. V. 1, Kushnir I.M. 2, Hunchak V.M.1, Hunchak A. V. 3, Khalak V.l. 4, Kushnir V.l. 2, Martyshuk T. V.1, Leskiv Kh. Ya.1, Gyta Z. A. 1
'Stepan Gzhytskyi National University of Veterinary Medicine and Biotechnologies of Lviv, Ukraine 2State Research Control Institute of veterinary medicinal products and feed additives, Lviv, Ukraine
3Institute of Animal Biology NAAS, Lviv, Ukraine 4State Institution Institute of Grain Crops NAAS of Ukraine, Dnipro, Ukraine
DOI: 10.24412/2520-6990-2022-18141-10-16 MORPHOLOGICAL PARAMETERS OF DOGS' BLOOD, WITH EXPERIMENTAL INFESTATION
WITH TOXOCARIASIS AND "FENBENZYL"
Abstract
The study aimed to determine the effect of "Fenbenzyl" on the morphological parameters of dogs' blood during experimental infestation with toxocariasis. The tests were performed on 18 dogs aged 2-4 months. It was found that with the use of fenbenzyl in infected dogs, the erythrocytes number and hemoglobin content on 25 and 30 days of the trial ranged within physiological values. The drug "Fenbenzyl" decreases the number of leukocytes within 10 days of the experiment. In the second group, the leukocyte number was more likely to decline compared with the control group. Such changes are due to the antiparasitic effect of the "Fenbenzyl" and the cessation of Toxocara toxins on the bone marrow. Eosinophils, neutrophils, and monocytes were significantly reduced in all groups when "Fenbenzyl" was administered to animals compared to untreated infected dogs. The lymphocyte number of the experimental dogs probably increased from the 15th day of the trial. On 25 and 30 test days, the lymphocyte number grew to physiological values in dogs treated with "Fenbenzyl". In our opinion, this is due to the reduction of the immunosuppressive effect of Toxocara and hepatoprotective, immunostimulatory and antiox-idant effects of milk thistle.
Keywords: toxocariasis, dogs, "Fenbendazole", "Fenbenzyl", leukogram, milk thistle.
Introduction
Among the invasive diseases of dogs, the most common in our country and abroad are helminths of the digestive tract, among which the top place is toxocariasis - nematode infestation of the order Ascaridata [1-3, 6, 24]. Infection of puppies mainly occurs in utero by transplacental transmission of larvae from mother to fetus in the second half of pregnancy or the first days of life with milk [7, 26]. The direct route of infection is by swallowing Toxocara eggs directly from the soil or contaminated soil. In the stomach or small intestine, larvae emerge from the eggs, similar to the larvae of A. suum in pigs [10, 11]. Through the intestinal mucosa, second-stage larvae enter the intestine and portal vein system venous vessels and enter the liver. Then into the inferior vena cava, right half of the heart, and pulmonary artery to the pulmonary capillaries, where the second molt occurs. From pulmonary capillary vessels, larvae of the third stage actively reach bronchioles, bronchial tubes, and trachea. Then, with mucus, they get to an oral cavity and are swallowed with saliva. In the small intestine, there are two more molts. In 4-5 weeks after infection, the parasites reach sexual maturity. This migration path is mainly registered in puppies under five weeks [2, 8, 25].
In adult dogs (older than one year), the larvae do not fully develop. It stops in the larvae of the second stage. Some larvae, reaching the lungs, and penetrating
the pulmonary vein, migrate through the heart into the great circle of blood circulation. The arterial system enters various organs and tissues (lungs, liver, kidneys, muscles), where they incise, maintaining viability for many years. In the case of reduced resistance or changes in hormone levels (pregnancy, lactation), the larvae leave their habitats [9, 22].
For treating carnivorous animals with toxocariasis are widely used drugs based on fenbendazole [15, 16, 20, 21]. They do not have sensitizing, carcinogenic, embryotoxic, mutagenic, teratogenic, and allergenic effects, do not irritate the skin and mucous membranes of animals and do not affect the course of pregnancy [18, 21].
Scientists have established the stimulating effect of milk thistle on animals' antioxidant and immune status under various negative factors [5, 17]. However, the complex application of milk thistle and fenbendazole on morphological and biochemical parameters of the blood of infected dogs is currently insufficiently covered in the scientific literature.
The study aimed to determine the effect of "Fenbenzyl" on the morphological parameters of dogs' blood during experimental infestation with toxocariasis.
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Material and methods of research
The research was performed on 18 dogs, 2-4 months of age. Three groups were formed of six animals each: control (C) and two experimental (E) groups. Puppies of all groups were experimentally infected with toxocariasis at a dose of 5,000 invasive T. canis eggs per kg. The control group of dogs was as untreated. Puppies of the Ei group were fed the drug "Fenbendazole" at 150 mg per 3 kg of animal weight once a day for three days in a single dose. Puppies of the E2 group were fed the drug "Fenbenzyl" (TU U 00492990-027: 2020 The drug "Fenbenzyl") [19] at a dose of 350 mg per 3 kg of animal weight once a day for three days.
The drug "Fenbenzyl" contains fenbendazole and milk thistle fruits. It was developed at the Department of Pharmacology and Toxicology and the Department of Parasitology and Ichthyopathology of S. Z. Gzhyt-sky National University of Veterinary Medicine and Biotechnology Lviv.
The erythrocyte and leukocyte numbers were counted on the Goryaev grid of the counting chamber according to the generally accepted method. The hemoglobin level in the blood was determined by the cyan-hemoglobin method using FEC-M by the method of G. V. Derviz and A.G. Vorobyov. Differential counting of leukocytes - microscopic examination of blood smears [23].
The analysis of research results was performed using the software package Statistica 6.0. The student's t-
Before 5 th day 10 th day treatment
Fig. 1.
With the decrease in the erythrocyte number, a decrease in hemoglobin was found. On the 10th and 15th days, the hemoglobin level of the C group declined by 15.6 and 19.8% compared with the initial values (Fig. 2). The use of "Fenbendazole" and "Fenbenzyl" in infected dogs showed a slight increase in the hemoglobin level on the 5th day. We noticed the rise in this indicator of the E1 group by 9.9%, E2 group - by 14.0% relative to the C group on the 10th day. The hemoglobin
test assessed the probability of differences. The results of the mean values were considered statistically significant at * - P <0.05, ** - P <0.01, *** - P <0.001 (ANOVA).
Results and discussion
It was found that the number of erythrocytes in the blood of the C group decreased throughout the experiment. On the 25 and 30 test days, we note a decline in the erythrocyte number relative to the initial values by 33.8 and 38.5%. However, the number of erythrocytes in the E1 group increased slightly with the "Fenbendazole" treatment. On the 20th day, the increase of this indicator by 15.2% compared to the indicators of the C group was set (Fig. 1).
The use of "Fenbenzyl" in infected dogs shows a more likely increase in the erythrocytes number compared to the E1 group. In the E2 group was found a probable growth in the erythrocytes number, starting from the 15th day of the research. According to the C group, this figure increased by 18.0%. The erythrocytes number in the blood of dogs treated with "Fenbenzyl" continued to grow. On the 20th and 25th days, this indicator raised by 30.4 and 44.2% compared with the C group. On the 30th day of the experiment, the erythrocytes number of the E1 group fluctuated within physiological values.
15 th day 20 th day 25 th day 30 th day
level was probably higher in the blood of dogs treated with the drug "Fenbencil" on the 20th day. During this experiment period, in the E2 group of dogs, the hemoglobin level was 118.6 ± 0.85 g / l, while in the E1 and C, it was 105.9 ± 1.14 and 95.1 ± 0.57 g/l. The highest hemoglobin level was on the 25th day in the E2 compared with the control group, which increased by 34.2%.
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toxocariasis (M ± m, n = 6)
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In toxocariasis, invasion in dogs showed an increase in the number of leukocytes, whereas, respectively, the control group of dogs found an increase in the studied index to 15.4 ± 0.30 G/l.
Analysis of the leukogram data of dogs infected with the toxocariasis pathogen showed that the ratio of certain classes of leukocytes changes significantly. For
example, in the C group of dogs, eosinophils increased to 13.98 ± 2.44%. At the same time, at the beginning of the research, this figure was 5.31 ± 1.14% (Fig. 3). The growth in the eosinophils number in the blood of the C group of dogs is characteristic of parasitological diseases.
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toxocariasis (M ± m, n = 6)
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Fig. 4. The "Fenbendazole" and "Fenbenzyl" effect on the eosinophils number in the blood of dogs infected
with toxocariasis (M ± m, n = 6)
After using fenbendazole in dogs of the E1 group, the eosinophils number in blood ranged from 7.83 ± 1.98 - 5.63 ± 2.45%. The highest number of eosinophils in the blood of this group was on the 20th day of the test. Using "Fenbenzyl" in infected dogs reduced the number of eosinophils in the E2 group throughout the research. Thus, on the 10th, 15th, and 20th days, this figure decreased by 2.34, 4.38, and 5.17%, compared with the C group of dogs.
The "Fenbendazole" and "Fenbenzyl" effect on the number of neutrophils in the blood of dogs infected with the toxocariasis pathogen is shown in fig. 5. It was found that the percentage of Escherichia coli neutrophils in the blood of infected dogs increases. Thus, the
7 -
number of rod neutrophils in the C group grew by 2.27% compared to baseline. Drug use showed a probable reduction in the indicator studied throughout the research. The number of rod neutrophils on the 15th day declined by 0.55% in the E1 group and 1.0% in the E2 group compared with the C group. On the 20th day, this indicator in the E2 group was 4.37 ± 0.86, significantly lower than in the E1 group5.34 ± 0.75%. The lowest number of rod-shaped neutrophils was in dogs of the E2 group at 25 and 30 days of the experiment, compared with the control group; this figure decreased by 1.62 and 2.0%.
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Fig. 5. The "Fenbendazole" and "Fenbenzyl" effect on the number of rod neutrophils in the blood of dogs
infected with toxocariasis (M ± m, n = 6)
Similar changes were found in determining the number of segmental neutrophils. They increased in animals of the C group to 62.13 ± 3.31% (Fig. 6). Decreased segmental neutrophils in the blood of dogs of both experimental groups were found when prescribing
"Fenbendazole" and "Fenbenzyl". However, when using the drug "Fenbenzyl" the number of segmental neutrophils declined slightly more than in animals of the E1 group. On the 25th day, the number of segmental neutrophils in the E1 group was 58.34 ± 2.78%, while in the E2 group 57.56 ± 3.19%.
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Fig. 6. The "Fenbendazole" and "Fenbenzyl" effect on the segmental neutrophils in the blood of dogs infected
with toxocariasis (М ± m, n = 6)
With the development of toxocariasis in dogs, a decrease in lymphocytes was found. The lymphocyte number throughout the experiment decreased by 10.8 days on the 10th day of the experiment. On the 15th day - by 10.49%, 20th day - by 13.39%, 25th day - by 16, 58%, 30 days - by 19.18% relative to the C group (Fig. 7). Reduces lymphocyte counts in sick animals indicate the development of secondary immunodeficiency.
When "Fenbendazole" and "Fenbenzyl" were used in dogs of the experimental groups, it was found
35
that the lymphocytes number was slightly higher than in the C group. Thus, with "Fenbendazole", on the 15th day, this number increased by 6.4%, while with the "Fenbenzyl" - by 8.77% relative to the C group. On the 20th and 25th day, we note the growth in this indicator in the E2 group, relative to the C group, increased by 10.81 and 13.57%, respectively.
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Fig. 7. The "Fenbendazole" and "Fenbenzyl" effect on the lymphocytes number in the blood of dogs infected
with toxocariasis (М ± m, n = 6)
Monocytes are part of the phagocytic system, which is involved in inflammatory processes. It was found that experimental toxocariasis in dogs increased their percentage in the blood to 6.59 ± 0.94%, while at the beginning of the trial, it was 4.35 ± 0.87%, respectively (Fig. 8). The "Fenbendazole" and "Fenbenzyl"
treatment shows that on the 10th day the monocyte number decreased by 0.45 and 0.8% relative to the C group. On the 15th day, this indicator of the E1 group was 4.98 ± 0.71%, while in the E2 - 4.56 ± 0.55%.
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10 th day 15 th day 20 th day 25 th day 30 th day
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Fig. 8. The "Fenbendazole" and "Fenbenzyl" effect on the monocytes number in the blood of dogs infected with
toxocariasis № ± m, n = 6)
The lowest number of monocytes was found on the 25th research day in the E2 group compared to the C group; this indicator decreased by 1.81%. In the Ei group, the number of monocytes in this period was 4.76 ± 1.01%, while in the C group - 6.21 ± 0.97%.
Conclusions
The "Fenbendazole" and "Fenbenzyl" introduction to dogs affects the TOrmalization of hematological parameters. It is indicated by an increase in the erythrocytes number, hemoglobin levels, and a decrease in the leukocytes number in their blood. It is also worth noting the positive changes in the leukogram of infected dogs using "Fenbendazole" and "Fenbenzyl". Finally, it should be noted that the best effect of the combined use of the drug "Fenbenzyl" is such active substances as "Fenbendazole" and milk thistle.
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