Numerous gram-negative phytopathogenic and zoopathogenic bacteria utilise acylated homoserine lactone (AHL) in communication systems, referred to as quorum sensing (QS), for induction of virulence factors and biofilm development. This phenomenon positions AHL-mediated QS as an attractive target for anti-infective therapy. This review focused on the most significant groups of plant-derived QS inhibitors and well-studied individual compounds for which in silico, in vitro and in vivo studies provide substantial knowledge about their modes of anti-QS activity. The current data about sulfur-containing compounds, monoterpenes and monoterpenoids, phenylpropanoids, benzoic acid derivatives, diarylheptanoids, coumarins, flavonoids and tannins were summarized; their plant sources, anti-QS effects and bioactivity mechanisms have also been summarized and discussed. Three variants of plant-derived molecules anti-QS strategies are proposed: (i) specific, via binding with LuxI-type AHL synthases and/or LuxR-type AHL receptor proteins, which have been shown for terpenes (carvacrol and l-carvone), phenylpropanoids (cinnamaldehyde and eugenol), flavonoid quercetin and ellagitannins; (ii) non-specific, by affecting the QS-related intracellular regulatory pathways by lowering regulatory small RNA expression (sulphur-containing compounds ajoene and iberin) or c-di-GMP metabolism reduction (coumarin); and (iii) indirect, via alteration of metabolic pathways involved in QS-dependent processes (vanillic acid and curcumin).

The results of a study of hematological parameters of bulls from the Simmental (group I) and Limousin (group II) breeds and their crossbreeds of different generations are given: ½ Limousin ½ Simmental (group III generation I), ¾ Limousin ¼ Simmental (group IV generation II), ⅞ Limousin ⅛ Simmental (group V generation III) in summer and winter seasons. It was established that the total protein content in blood serum of calves from groups I and IV increased in summer period by 5.40 g/l (7.9%) and 2.01 g/l (2.9%) compared with winter season. n insignificant decrease in the studied indicator was noted in young animals of other groups. The concentration of albumin in blood serum of bulls from experimental groups was like a change in the content of total protein. The change in the total amount of globulins in blood of bulls with different genotypes was not the same. So, in summer compared to winter, their number in calves of the Simmental breed increased by 2.09 g/l (5.6%), and in Limousins and crossbreeds it decreased by 0.53 g/l (1.4%) and by 0.85-5.02 g/l (2.2-13.8%). It was established that the crossbreed bulls had more intensive process of increasing aminotransferase activity than purebred young animals.

The development of research methods of sampling of beef cattle hair are given in the article. Data on filthiness, growth and elemental composition of different components of hair were taken into account. Hair from mature beef cattle (Bos Taurus) was used. Animals were of Hereford and Angus breeds. Hair sampling of one and the same animals was performed in winter and summer period. Hair for study was cut from six areas: back of head, the first tail vertebra, projection of the 12th rib median line, dewlap, withers, switch. Elemental composition of hair and its components was tested by 25 chemical elements. It was observed that guard hair from withers is the fastest growing (0.38±0.033 mm/d). Hair from withers (8.14±1.02% in winter period and 4.80±0.83 in summer period) and dewlap were with less dirt. No correlation between area of samples and its elemental composition was observed. Down hair contained more cobalt, manganese and nickel compared to guard hair of the animals. It was found that average sample of hair from withers is more preferable for research of elemental composition. It is recommended to use the developed method in science and agricultural industry for assessment of elemental composition of beef cattle hair.

This study was designed to investigate the synergistic effect of the combined action of probiotic bacterial strains

The cecal microbial community plays an important role in chicken growth and development via effective feed conversion and essential metabolite production. The aim of this study was to define the microbial community’s variants in chickens’ ceca and to explore the most significant association between the microbiome compositions and poultry farming productivity. The meta-analysis included original data from 8 control broiler chicken groups fed with a standard basic diet and 32 experimental groups supplemented with various feed additives. Standard Illumina 16S-RNA gene sequencing technology was used to characterize the chicken cecal microbiome. Zootechnical data sets integrated with the European Production Effectiveness Factor (EPEF) were collected. Analysis of the bacterial taxa abundance and co-occurrence in chicken cecal microbiomes revealed two alternative patterns: Bacteroidota-dominated with decreased alpha biodiversity; and Bacillota-enriched, which included the Actinomycetota, Cyanobacteriota and Thermodesulfobacteriota phyla members, with increased biodiversity indices. Bacillota-enriched microbiome groups showed elevated total feed intake (especially due to the starter feed intake) and final body weight, and high EPEF values, while Bacteroidota-dominated microbiomes were negatively associated with poultry farming productivity. The meta-analysis results lay the basis for the development of chicken growth-promoting feed supplementations, aimed at the stimulation of beneficial and inhibition of harmful bacterial patterns, where relevant metagenomic data can be a tool for their control and selection.

Background and Aim: Progressive antibiotic resistance has become the primary threat to public health. The search for alternative substances with similar effects is now a global challenge for poultry farming. The aim of this study was to investigate the action of the probiotic Bacillus cereus (BC) and coumarin (CO) on broiler productivity, biochemical indicators of blood, and muscular and liver tissues. Materials and Methods: The trial of this study included Arbor Acres cross broiler chickens that were grown up to the age of 42 days. The experiment was conducted on 200 broiler chickens divided into four experimental groups of 50 individuals each: The control group received ration without additives (main ration [MR]), the first experimental group received MR+BC, the second received MR+CO, and the third received –MR+BC+CO. A biochemical and hematological analyzer was used to estimate elemental concentrations using inductively coupled plasma mass spectrometry and inductively coupled plasma atomic emission spectrometry. Results: Inclusion of CO and CO+BC in the diet improved growth rates and reduced feed consumption (FC) per kg of live weight gain. Decreased white blood cell count, increased creatinine and triglycerides (CO), changes in aminotransferase and transpeptidase activity, and increases in chemical elements in the liver and pectoral muscles (BC+CO) were observed. The inclusion of BC+CO in the diet contributed to increases in a greater number of chemical elements in the liver (calcium [Ca], K, magnesium, Mn, Si, and Zn) and the pectoral muscles (Ca, Na, Co, Cu, Fe, Mn, Ni, and Zn). Conclusion: The inclusion of CO and CO+BC in the diet improves growth rates and reduces FC in broilers against a background of the absence of mortality during the experiment.