No abstract

The article presents data on the peculiarities of the bacteriocenoses formation in calves in different technological periods of raising and different animal housing systems. It has been shown that in calves up to three days of age the quantitative content of microorganisms is minimal. The amount of bifidobacteria and lactobacilli does not exceed 3 log CFU/g. In calves older than three days of age, their level increased, and depending on the method of housing, ranged from 5 log CFU/g (in calves with group housing) to 8 log CFU/g (in calves with individual housing). The microbiocenosis in calves with an individual housing system was characterized by a more constant and less variable composition of Escherichia coli (4 ± 0.8×102 CFU/g) and bacillary spore microflora (3 ± 1.3×101 CFU/g). In case of the group housing of calves, the content of bifidobacteria was lower (20.9 ± 5.5×106 CFU/g), and the content of E. coli and saprophytic microorganisms of the genus Bacillus was high and more variable (30 ± 20.4×105 CFU/g and 31 ± 11.3×102 CFU/g respectively). In calves older than fifteen days of age, the amount of lactobacilli ranged from 6 to 8 log CFU/g, and the number of bifidobacteria ranged from 7 to 10 log CFU/g. Thus, to exclude dysbiotic disorders, it is necessary to maintain the optimal composition and quantitative level of the main microflora of the intestinal tract, in particular the number of lactobacilli should be at least 6 log CFU/g, bifidobacteria at least 7 log CFU/g, E. coli no more than 7 log CFU/g (except for calves under three days of age)

The article presents the results of determining the feasibility and efficiency of the vaccine for the prevention of associated diseases in a farm with a high level of animal morbidity and the circulation of multidrug-resistant pathogens. The incidence of pneumoenteritis in calves was 38.0%, the incidence of various forms of mastitis and endometritis in cows was 48.2% and 76.2%, respectively. The causative agents of escherichiosis (Escherichia coli), staphylococcosis (Staphylococcus aureus), anaerobic enterotoxemia (Clostridium perfringens), and a number of opportunistic pathogens that were involved in complicating the associated course of the disease, were isolated from sick animals. The isolated microflora was resistant to penicillin drugs, aminoglycosides, macrolides, amphenicols, lincosamides, cephalosporins and even to some fluoroquinolones. In addition, it was found that probiotic cultures of the genus Bacillus had more pronounced antagonistic activity against isolated pathogens, so it is advisable to use them in disease outbreaks to displace pathogenic microflora from the source of infection. In the prevention of the disease and for normalization of the microflora after the use of antibacterial drugs, it is advisable to use probiotics based on lactobacilli, as they have the highest adhesion (from 6.4 ± 0.6 to 8.9 ± 0.4). Vaccination has contributed to a decrease in animal morbidity. The incidence in vaccinated cows was lower than in the control group, in particular the incidence of mastitis was lower by 15–25%; manure retention — by 15–32.7%, endometritis — by 17–30%. Double vaccination of dry cows provides the formation of colostral immunity in calves and 20% decrease in the incidence of respiratory and gastrointestinal diseases in calves. In addition, vaccination of cows helped to improve the quality of milk by the degree of its contamination with bacterial microflora