Search

Silage is one of the most common feedstuffs used in modern dairy and beef farms, but silage quality is often measured without assessing the presence of pathogens. However, poorly prepared or contaminated silage can contain pathogens that reduce animal performance, cause bovine disease, and pose a threat to human health. The aim of this study was to analyse changes in the diversity of the silage microbial community during the ensiling process and to evaluate the effectiveness of two strains of promising microorganisms for use as inoculants. As a result of the study, it was shown that epiphytic microbiota has less potential to rapidly create and, most importantly, maintain high acidity conditions. The highest proportion of lactic acid bacteria was found in the variants with the introduction of strains of Lactobacillus plantarum and Bacillus subtilis at almost all stages of ensiling, indicating that the ensiling process was proceeding correctly in these variants. The lowest number of bacteria belonging to the Enterobacteriaceae family was found in the variant with the L. plantarum strain. Some microorganisms were detected in the silage, including mammalian pathogens: representatives of the genera Staphylococcus, Erysipelothrix, and Fusobacterium.

Diseases that occur in such a multifactorial system as animal husbandry are determined not only by internal factors of the body, for example, the composition of the microflora of the digestive system, but also by external factors, such as feed. The aim of the study was to analyze the similarity of the microbiota of silage fed to cows with the composition of the microflora of their rumen and milk using the NGS sequencing method. The experiment was carried out on one of the commercial farms of the Leningrad region. The bacterial community of the contents of rumen, milk and silage from perennial cereals and legumes was evaluated by NGS sequencing on the MiSeq platform (Illumina, Inc., USA) with primers for the V3-V4 region of the 16S rRNA gene. As a result of the study, 22 phylum of attributed microorganisms were found in the microflora of silage, 24 to 30 phylum of rumen, 18 phylum of milk. Similar taxa of microorganisms were identified in silage, rumen and milk, the main difference was noted in quantitative ratios (P≤0.05). For example, the amount of Firmicutes in silage was 52.9 ± 3.45%, in milk - 11.8 ± 0.78%. This suggests that there may be some relationship between the studied biotopes. Pathogenic microorganisms, including the causative agents of mastitis, were present in many samples. The genera Staphylococcus, Acinetobacter, Streptococcus and Fusobacterium were identified by us as the most represented (P≤0.05) in the composition of the milk microflora. Their content was 0.24±0.023, 1.8±1.23, 1.0±0.06 and 0.35±0.031%, respectively. Probably, the microflora of the rumen can influence the formation of the milk microbiota.

The aim of the study was to study the effect of different concentrations of glyphosate on meat productivity and differential expression of genes for immunity and broiler productivity. Broilers were divided into groups: Control I, who received a diet without the introduction of glyphosate, Experimental II, who received a diet with the addition of glyphosate at a dose of 10 mg/kg of feed (0.5 MPC for food); Experimental III, who received a diet with the addition of glyphosate at a dose of 20 mg/kg of feed (1 MPC); Experimental IV, who received a diet with the addition of glyphosate at a dose of 100 mg/kg of feed (5 MPC). Transcriptome analysis was performed by RNA-seq on the Illumina Miseq platform, using the TruSeq Stranded mRNA kit (Illumina, USA). In the 22-28-day period of broiler rearing, a decrease in live weight gain (83 g less) was observed in Experimental group III compared to Control I (P≤0.05). It has been shown that glyphosate at the level of 1 and 5 MPC for food causes activation (P≤0.05) of the proinflammatory response genes (IL15, IL1B, IL34, IL22) and apoptosis (Casp1, Casp2, Casp6, Casp7, Casp8, Casp9) up to 31.1 times, which probably leads to the redistribution of nutrients in in the body towards the immune system, reducing the functions of absorption in the intestine. In parallel, there is an inhibition (P≤0.05) of the expression of genes that have a direct effect on growth and development, which ultimately leads to a decrease in poultry meat productivity. Exposure to glyphosate is an important but unaccounted-for risk factor for reducing meat productivity in birds, acting through a change in gene expression.

Despite the attention given in the recent years to the microbiological causes of endometritis and the potential sources of uterine microbiota infestation, more questions than answers remain in this research field. This paper describes an experiment carried out at the livestock farm of the Leningrad region on 6 dairy cows of the Holsteinized Russian Black Pied breed of the second lactation in the period after calving. The animals were divided into two groups (n = 3): Group 1 included clinically healthy animals, Group 2 included animals diagnosed with purulent-catarrhal post-calving endometritis. Metagenomic sequencing was performed using the MiSeq genomic sequencer (Illumina, Inc., USA) with the MiSeq Reagent Kit v3 (Illumina, Inc., USA). Based on the next-generation sequencing of microbiota of endometrial scrapings, 7 phyla of microorganisms were detected in clinically healthy cows and only 4 phyla of microorganisms in cows diagnosed with endometritis. The increase in the proportion of Fusobacteriota taxon bacteria permanently present in endometrial scrapings and the decrease in Bacteroidota phylum bacteria in the group of animals with endometritis could be related to the occurrence of this disease. Bacteria Alloprevotella, Campylobacter, Caviibacter, Falsiporphyromonas, Veillonella present only in the endometrial tissue of sick cows may be the etiological origin of endometritis. In the rumen of animals with endometritis, there was an increase in Bacteroidota phylum microorganisms (p≤0.05) against a decrease in Firmicutes phylum bacteria (p≤0.05) compared to the clinically healthy group. Using the PICRUSt2 software package (v.2.3.0), it was shown that the microbiome of cows diagnosed with endometritis showed inhibition (p≤0.05) of the potential of 9 metabolic pathways compared to healthy animals. This could have negative consequences for the body of animals and be a consequence of metabolic disorders.

To increase the production efficiency and competitiveness of livestock products, the rearing of young calves is important, one of the main conditions of which is a full-fledged feeding. An indispensable task is to create conditions in the rumen of ruminants in which feed mixtures are maximally digested and assimilated, and also serve as preventive measures against diseases. For these purposes, on the basis of two farms of the Vologda Oblast (Ltd "Zazerkal'e" and SPK "Kolkhoz Andoga") we conducted a scientific-economic experience of using the probiotic preparation "Rumit" in feeding the Russian Black Pied calves during dairy rearing period. For this purpose, we formed two groups of animals at the age of 2 months in experimental farms by paired-analogy method; each group contained 10 animals. The experimental group was fed Rumit supplement in addition to the basic diet at the rate of 15 g per day per head. The duration of feeding the probiotic was 90 days. We found that the calves of Ltd "Zazerkal'e", which received the biological preparation in addition to the basic ration, in comparison with the control group showed the increase in the total blood protein content by 5.3% (p>0.95) and decrease in the urea and creatinine concentration by 8.2 and 8.1% respectively. In SPK "Kolkhoz Andoga", we noted an increase of total protein content in blood by 7.8% (p>0.95), glucose by 21.5% (p>0.95). We established that blood urea decreased by 12.5% (p>0.95), bilirubin and cholesterol by 5.5 and 11.8% (p>0.95) respectively. When analyzing the calf growth dynamics during the dairy rearing period, the calves of the experimental groups were characterized the higher absolute and average daily growth. Calves in SPK "Kolkhoz Andoga" had a difference of 3.8 and 4.6% compared to the control group, in Ltd "Zazerkal'e" - 4.8 and 4.5% respectively. Consequently, the use of the probiotic based on cellulolytic bacteria in calf feeding had a positive effect on the level of metabolic processes and growth rate of young animals. [ABSTRACT FROM AUTHOR]

The main purpose of the research was to study the effect of "Rumit" enzyme-probiotic additive, obtained on the basis of reindeer rumen microorganisms (Rangifer tarandus), on the population and generic diversity of rumen protists of lactating Russian Black Pied and Ayrshire cows. In the conditions of one farm with the same feeding rations, control and experimental groups of two breeds of 15 animals each were formed. For 90 days, the experimental groups received 50 g per day of a probiotic preparation in addition to the main diet. At the beginning and at the end of the experiment, the contents of the rumen were selected for counting and determining the generic composition of the ciliate fauna. At the beginning of the experiment, the same density and uniform population of protists were determined in all groups. The use of the probiotic contributed to the growth of the rumen microfauna. In the experimental group of the Russian Black Pied cattle, the density of the ciliate fauna was 2 times higher than in the control group (p>0.95). In cows of the Ayrshire breed of the experimental group, in the cicatricial content, the population of ciliates exceeded this indicator of the control by 237.2 thousand ind./ml. Also, the use of probiotics led to the emergence of new genera of protists and their active reproduction. It was concluded that the drug "Rumit" had a positive effect on the density and generic composition of the ciliate fauna of the rumen of cows, which indicates the optimal parameters of its functioning and the state of health of animals in general. [ABSTRACT FROM AUTHOR]