Seasonal and age dynamics of rabbits infestation with spirochetosis in the southern and northern regions of Ukraine

Abstract

In the age and seasonal aspect, the peak of spirochetosis infection is observed in rabbits aged 3–4 months in the autumn. A significant increase in the extent and intensity of damage to rabbits by the pathogen spirochetosis was registered from July to October with a peak in September (EI = 69.81 %, II = 1080.19 ± 83.40 pathogens per 1 g of feces). The average infestation of rabbits by pathogen Treponema cuniculi was 24.82 %. The largest number of sick animals was registered in the Cherkasy region. The goal of the work: determining the influence of age and seasons on the dynamics of the disease of spirochetosis of rabbits of the Californian breed of yard maintenance in different natural and climatic zones. The work was carried out during 2014–2020 in the conditions of a private enterprise for breeding rabbits of the Californian breed, which used cage keeping of animals without air conditioning in compliance with all zoohygienic requirements. Darkfield microscopy was used to detect Treponema cuniculi. The obtained results and calculated averages for animal age and seasons were counted using Microsoft Excel-16. The results of parasitological studies indicate that spirochetosis in rabbits is registered during the year, but the maximum incidence of animals was established in the summer-autumn period of the year, when EI reached 39.92 % and 46.15 %, for II 423.57 ± 52.50 ekz./g and 628.21 ± 50.86 ekz./g. In winter, the rates of animal infestation reached the minimum values (EI = 8.17 %, II = 12.74 ± 2.96), and with the onset of spring rose again (EI = 13.64%, II = 22.73 ± 3.93), in the summer the rise continued (EI = 39.92%, II = 423.57 ± 52.50), reaching a maximum in autumn (EI = 46.15 %, II = 628.21 ± 50.86). A significant increase in the extent of damage to rabbits by the causative agent of spirochetosis was registered from July to October with a peak in September (EI = 69.81 %). In November, the infestation decreased sharply and remained low in winter until mid-spring, with the lowest value observed in February (6.86 %). The peak level of spirochetes in rabbits was registered in September and was equal to 1080.19 ± 83.40 pathogens in 1 g of feces, and a decrease in the biopotential of parasites is observed in February (II = 9.80 ± 4.06 pathogens in 1 g of feces). It was found that the invasiveness of Treponema cuniculi rabbits increases with age from 2–4 months of age (EI from 88.23 % to 88.89 %, with the intensity of the lesion from 794.11 ± 108.62 to 1688.89 ± 253.01 pathogens in 1 g of feces. From 5 months of age to 1–2 years, the rates of infection are gradually reduced: EI to 82.75 %, with the intensity of the lesion to 924.14 ± 109.26 pathogens in 1 g of feces. During the studying period, rabbits of private households located in the Forest-Steppe zone were found. Rabbits of private households, which were located in the Forest-Steppe zone, were the most unfavourable for spirochetosis during the study period.