Intestinal Helminths and the Influence of Environmental Factors on Cattle Infection in the Altai Mountains

Abstract

The purpose of the research: comparative assessment of cattle infection with intestinal helminths in various provinces and characteristics of the relationship between abiotic and anthropogenic environmental factors with the level of infection and the number of helminths in the Altai Mountains. Materials and methods. According to the results of long-term (2010–2019) ovolarvoscopic examinations, more than 2.4 thousand heads of cattle from 7 regions of the Altai Republic characterized by extensity of infection (EI) and the number of helminth eggs in 1 g of feces (NHE/g) in animals. By correlation analysis, the association of animal EI with helminths, NHE/g and abiotic and anthropogenic environmental factors in the context of farms and regions of the Altai Mountains is shown. The following parameters are estimated: long-term average annual temperature, long-term average annual rainfall, longterm average summer temperature, long-term average summer rainfall, altitude above the sea level, population density of the host, the effect of parasiticidal treatments of animals on parasite infection. Results and discussion. It was found that animals are mostly infected with intestinal helminths in the Choy region, where the EI was 61.7% when detecting NHE/g 81.8 pcs. Minimal infection of cattle by helminths was recorded in the Kosh-Agach region – 38.8% with NHE/g of 22.9 pcs. In the whole country, EI of animals is 51.8% with an egg number of 44.1 individuals in 1 g of feces. Within the physical-geographical provinces, cattle are mostly infected in Central Altai (EI – 56.5%, NHE/g – 43.6 pcs.), to a lesser extent in Southeast Altai (EI – 38.8%, NHE/g – 22.9 pcs.). According to the results of ovoscopic examinations, it was found that the most significant factors affecting the infection of animals with intestinal helminths in farms are the long-term average annual precipitation (r = 0.60 and 0.34) and the degree of anthropogenic pressure (r = -0.52 and -0.59), in the context of districts, long-term average annual temperatures (r = 0.65 and 0.55), average annual summer rainfall (r = 0.74 and 0.65). According to larvoscopy, the most significant environmental factors affecting cattle infection are long-term average annual temperature (r = 0.62 and 0.72), long-term average annual rainfall (r = 0.76) and elevation (r = -0.71 and -0.73), in farms – the degree of anthropogenic press (r = -0.65 and -0.78).