Genetic diversity and phylogenetic relationships of Streptococcus thermophilus isolates from traditional Turkish yogurt: multilocus sequence typing (MLST).

Yogurt, a globally consumed fermented dairy product, is recognized for its taste and potential health benefits attributed to probiotic bacteria, particularly Streptococcus thermophilus. In this study, we employed Multilocus Sequence Typing (MLST) to investigate the genetic diversity and phylogenetic relationships of 13 S. thermophilus isolates from traditional Turkish yogurt samples. We also assessed potential correlations between genetic traits and geographic origins. The isolates were identified as S. thermophilus using VITEK® MALDI-TOF MS, ribotyping, and 16S rRNA analysis methods. MLST analysis revealed 13 different sequence types (STs), with seven new STs for Turkey. The most prevalent STs were ST/83 (n = 3), ST/135 (n = 2), and ST/134 (n = 2). eBURST analysis showed that these isolates mainly were singletons (n = 7) defined as sequence types (STs) that cannot be assigned to any group and differ at two or more alleles from every other ST in the sample. This information suggests that the isolates under study were genetically distinct from the other isolates in the dataset, highlighting their unique genetic profiles within the population. Genetic diversity analysis of ten housekeeping genes revealed polymorphism, with some genes showing higher allelic variation than others. Tajima's D values suggested that selection pressures differed among these genes, with some being more conserved, likely due to their vital functions. Phylogenetic analysis revealed distinct genetic diversity between Turkish isolates and European and Asian counterparts. These findings demonstrate the genetic diversity of S. thermophilus isolates in Turkish yogurt and highlight their unique evolutionary patterns. This research contributes to our understanding of local microbial diversity associated with yogurt production in Turkey and holds the potential for identifyic strains with enhanced functional attributes.

Comprehensive analysis of the CRISPR-Cas systems in Streptococcus thermophilus strains isolated from traditional yogurts.

Phage resistance is crucial for lactic acid bacteria in the dairy industry. However, identifying all phages affecting these bacteria is challenging. CRISPR-Cas systems offer a resistance mechanism developed by bacteria and archaea against phages and plasmids. In this study, 11 S. thermophilus strains from traditional yogurts underwent analysis using next-generation sequencing (NGS) and bioinformatics tools. Initial characterization involved molecular ribotyping. Bioinformatics analysis of the NGS raw data revealed that all 11 strains possessed at least one CRISPR type. A total of 21 CRISPR loci were identified, belonging to CRISPR types II-A, II-C, and III-A, including 13 Type II-A, 1 Type III-C, and 7 Type III-A CRISPR types. By analyzing spacer sequences in S. thermophilus bacterial genomes and matching them with phage/plasmid genomes, notable strains emerged. SY9 showed prominence with 132 phage matches and 30 plasmid matches, followed by SY12 with 35 phage matches and 25 plasmid matches, and SY18 with 49 phage matches and 13 plasmid matches. These findings indicate the potential of S. thermophilus strains in phage/plasmid resistance for selecting starter cultures, ultimately improving the quality and quantity of dairy products. Nevertheless, further research is required to validate these results and explore the practical applications of this approach.

Meta-analysis to predict the effects of probiotics on meat quality of broiler.

The demand for chicken meat has surged globally due to its status as a primary protein source in human diets. However, ensuring high-quality meat products has become an increasingly important subject to consumers. In this study, 21 articles from PubMed and Web of Science databases published between 2005 and 2023 were examined to assess the influence of probiotic supplementation on broiler meat quality. The meta-analysis revealed significant findings across various meat quality parameters. Specifically, probiotics were found to significantly affect meat colour parameters, including redness, yellowness, and lightness, in both breast and thigh meat samples. Moreover, significant differences were observed in parameters such as water-holding capacity (p < 0.001), cook loss (p = 0.047), and shear force (p = 0.025) between control and probiotic groups. However, it's essential to note the considerable heterogeneity among the studies, emphasising the need for a cautious interpretation of the results. Despite this variability, the study underscores the potential of probiotics to positively influence broiler meat quality, highlighting avenues for further research and standardisation in poultry production practices. These findings also contribute to a better understanding of probiotics' role in improving meat quality and meeting consumer preferences for nutritious and high-quality poultry products.

Clostridium perfringens Contamination in Retail Meat and Meat-Based Products in Bursa, Turkey.

This study examined the incidence of Clostridium perfringens in raw, ready-to-cook (RTC), and ready-to-eat (RTE) meat and meat-based products (N = 306) collected from restaurants, supermarkets, and butcher shops in Bursa, Turkey. In addition, we investigated the presence of the C. perfringens enterotoxin (CPE), as well as cpe genes and their source (chromosomal or plasmid borne). In this study, tryptose sulfite cycloserine (TSC) agar for classic culture isolation and API and real-time polymerase chain reaction (RT-PCR) techniques were used to identify C. perfringens and detect cpa and cpe genes from these products, respectively. Seventeen C. perfringens isolates (5.6%) were isolated and identified with API 20A. In addition, 42 of 81 suspicious isolates (51.9%) were identified as C. perfringens using RT-PCR. Of the 81 suspicious isolates tested by RT-PCR, 22 (27.2%) carried the cpe gene either on the plasmid or chromosome. Twenty-one isolates were positive for chromosomal cpe (C-cpe), and one was positive for plasmid-borne cpe (P-cpe). CPE was detected in 31.8% (7/22) of the cpe positive isolates by the PET-RPLA test. In conclusion, C. perfringens and their CPEs were present in raw, RTC, and RTE meat and meat-based foods in this study. It is emphasized that the presence of C. perfringens and the cpe gene in these foods may be a potential risk for human health.

Effects of Supplemental Mannanoligosaccharides on Growth Performance, Faecal Characteristics and Health in Dairy Calves.

Twenty Holstein calves were used to investigate the effects of mannanoligosaccharides (MOS) supplementation in the whole milk on growth performance, faecal score, faecal pH, selected faecal bacterial populations and health during the preweaning period. Healthy calves selected by clinical examination were allocated to one of the two groups (control [CG] and experimental [EG]) at 5 days old. Each group consisted of 5 male and 5 female calves. Each calf in EG was supplemented with 7 g/d of a MOS product (Celmanax) from 5 days to 56 days of age. MOS supplement was mixed with the whole milk once in the morning and administered to the calves in EG via nipple bottle, whereas the calves in CG were fed the whole milk without MOS. Calves were weaned at 56 days of age. The final body weight, average daily weight gain (ADG) and average daily feed intake (ADFI) were statistically similar (p>0.05) but were higher by 3.70%, 6.66%, and 10.97%, respectively, in MOS than in control calves. Feed efficiency (ADG/ADFI) was also similar in two calves group. While faecal scores did not differ on day 5, 7, 14, 21, 28, 42, 49, and 56 between groups, EG had a higher faecal score (p = 0.05) than CG on day 35. Faecal concentration of Lactobacillus was lower (p<0.05) in EG compared with CG. No differences (p>0.05) in faecal concentrations of Bifidobacterium, Clostridium perfringens, and Escherichia coli were found between groups. Although there were no significant differences (p>0.05) in the incidence of diarrhoea, treatment days for diarrhoea and the costs associated with diarrhoea treatments between groups, collectively, the observed reductions in treatment days and the cost of diarrhoea treatments accompanying increases in final body weight, ADG and ADFI for EG may indicate potential benefit of MOS in treatment of diarrhoea.

The concentrations of adipokines in goat milk: relation to plasma levels, inflammatory status, milk quality and composition.

The main objectives of our study were to measure the major adipokines adiponectin, leptin and resistin in goat milk, to assess their interrelationships and to assess their relationships with the plasma and serum concentrations of total protein, cholesterol, total lipids, plasma C-reactive protein (CRP), milk somatic cell count (SCC), milk total aerobic colony and lactobacillus count, and milk components in lactating Saanen goats. The study was performed on eighteen lactating Saanen goats. Milk and blood samples were collected on days 20, 35, 50, 65 and 80 of lactation postpartum. The milk and plasma adiponectin levels on days 50, 65 and 80 postpartum were significantly higher than those on day 20. The milk and plasma leptin levels were lower on day 20 than on days 35, 50, 65 and 80. The milk concentrations of these major adipokines were positively intercorrelated. The milk and plasma concentrations of these three adipokines were also positively correlated. The plasma CRP concentrations correlated positively with milk leptin and resistin concentrations and inversely with milk adiponectin concentration. Milk adiponectin concentration was inversely related with its SCC. These data confirm that adiponectin, leptin and resistin are present in goat milk. The milk concentrations of these three adipokines were interrelated and interacted with the general inflammatory marker, CRP. The inverse relationship between milk adiponectin concentrations and its SCC suggests that variations in milk adiponectin might be involved in the udder health of lactating goats, but clinical trials are needed to support this hypothesis.

Major causes of organ/carcass condemnation and financial loss estimation in animals slaughtered at two abattoirs in Bursa Province, Turkey.

An abattoir survey was conducted from July 2012 to December 2012 to determine the major causes of organ and carcass condemnation and to estimate the associated direct financial loss at two abattoirs in Bursa Province in Turkey. A total of 22,872 sheeps and 5363 cattle were examined by postmortem inspection using standard inspection procedures. The total economic loss in two abattoirs was estimated from the summation of organ and carcass condemnation in six-month period. The retail prices of offal (lung, liver, kidney, heart, and spleen) and kg price of cattle and sheep carcasses were obtained from local markets. The results of postmortem examination indicated that a total of 658 (2.33%) offals and 93 (0.32%) carcasses were condemned. While the main causes of organ condemnation were hydatidosis and fasciolosis, carcasses were condemned mainly due to tuberculosis and jaundice. The total revenue in 2012 for all animals (164,080 sheeps and 56,035 cattle) slaughtered in 15 abattoirs in Bursa Province was 144,401,765 USD. This study showed that financial loss due to organ and carcass condemnations at two abattoirs in six-month period was 245,483 USD (0.17% of the total annual revenue of all slaughtered animals at 15 abattoirs). In sheep, six-month financial loss was estimated at 3281 USD and 4015 USD from organ condemnation due to fasciolosis and hydatidosis, respectively. In cattle, total loss was calculated as 4042 USD and 12,321 USD due to fasciolosis and hydatidosis, respectively. A common cause of carcass condemnation in cattle was tuberculosis, totalling 214,995 USD in losses, whereas condemnation due to tuberculosis was not determined in sheep. The current study also showed that six-month monetary losses from carcass condemnation of sheep and cattle due to jaundice were 8099 USD and 6026 USD, respectively. From the data obtained in this study, it can be concluded that bacterial and parasitic diseases remain common and cause considerable economic loss in Bursa Province, Turkey. The result of this abattoir study provided regional information on major causes of organ and carcass condemnation in sheep and cattle slaughtered at two abattoirs as well as giving an estimation of the direct financial losses.