A comparative study of the bacterial diversity and composition of nursery piglets' oral fluid, feces, and housing environment

The oral cavity is the portal of entry for many microorganisms that affect swine, and the swine oral fluid has been used as a specimen for the diagnosis of several infectious diseases. The oral microbiota has been shown to play important roles in humans, such as protection against non-indigenous bacteria. In swine, studies that have investigated the microbial composition of the oral cavity of pigs are scarce. This study aimed to characterize the oral fluid microbiota of weaned pigs from five commercial farms in Brazil and compare it to their respective fecal and environmental microbiotas. Bacterial compositions were determined by 16S rRNA gene sequencing and analyzed in R Studio. Oral fluid samples were significantly less diverse (alpha diversity) than pen floor and fecal samples (P < 0.01). Alpha diversity changed among farms in oral fluid and pen floor samples, but no differences were observed in fecal samples. Permutational ANOVA revealed that beta diversity was significantly different among sample types (P = 0.001) and farms (P = 0.001), with separation of sample types (feces, pen floor, and oral fluid) on the principal coordinates analysis. Most counts obtained from oral fluid samples were classified as Firmicutes (80.4%) and Proteobacteria (7.7%). The genera Streptococcus, members of the Pasteurellaceae family, and Veillonella were differentially abundant in oral fluid samples when compared to fecal samples, in which Streptococcus was identified as a core genus that was strongly correlated (SparCC) with other taxa. Firmicutes and Bacteroidota were the most relatively abundant phyla identified in fecal and pen floor samples, and Prevotella_9 was the most classified genus. No differentially abundant taxa were identified when comparing fecal samples and pen floor samples. We concluded that under the conditions of our study, the oral fluid microbiota of weaned piglets is different (beta diversity) and less diverse (alpha diversity) than the fecal and environmental microbiotas. Several differentially abundant taxa were identified in the oral fluid samples, and some have been described as important colonizers of the oral cavity in human microbiome studies. Further understanding of the relationship between the oral fluid microbiota and swine is necessary and would create opportunities for the development of innovative solutions that target the microbiota to improve swine health and production.

Difficulties in Establishing the Adverse Effects of β-Casomorphin-7 Released from β-Casein Variants-A Review

β-Casomorphin-7 (BCM-7) is a peptide released through the proteolysis of β-casein (β-CN), which is considered a bioactive peptide displaying evidence of promoting the binding and activation of the μ-opioid receptor located in various body parts, such as the gastrointestinal tract, the immune system and potentially the central nervous system. The possible effects of BCM-7 on health are a theme rising in popularity due to evidence found in several studies on the modulation of gastrointestinal proinflammatory responses that can trigger digestive symptoms, such as abdominal discomfort. With the advancement of studies, the hypothesis that there is a correlation of the possible effects of BCM-7 with the microbiota-gut-brain axis has been established. However, some studies have suggested the possibility that these adverse effects are restricted to a portion of the population, and the topic is controversial due to the small number of in vivo studies, which makes it difficult to obtain more conclusive results. In addition, a threshold of exposure to BCM-7 has not yet been established to clarify the potential of this peptide to trigger physiological responses at gastrointestinal and systemic levels. The proportion of the population that can be considered more susceptible to the effects of BCM-7 are evidenced in the literature review. The challenges of establishing the adverse effects of BCM-7 are discussed, including the importance of quantifying the BCM-7 release in the different β-CN genotypes. In summary, the reviewed literature provides plausible indications of the hypothesis of a relationship between β-CN A1/BCM-7 and adverse health effects; however, there is need for further, especially in vivo studies, to better understand and confirm the physiological effects of this peptide.

Effect of cow’s milk with different PUFA n-6: n-3 ratios on performance, serum lipid profile, and blood parameters of grower gilts

The concern with human health has increased the interest in producing foods enriched with polyunsaturated fatty acids (PUFA), directly or naturally, by inclusion in the animals’ diet. The positive effects such as antithrombotic, anti-inflammatory, and hypolipidemic have been observed in pigs and rats, used as human models for study. The present study evaluated the effect of cow’s milk with different lipid profiles on performance, serum fatty acid profile, biochemical analysis, and a complete blood count of gilts used as a human model. At 34 days, thirty gilts were equally distributed in three treatments. Experimental treatments were milk from cows without the oil supplementation (C), milk from cows fed an enriched diet with linseed oil (n-3), and milk from cows fed an enriched diet with soybean oil (n-6). Milk supplementation was performed until 190 days old, provided once in the morning. The n-3 and n-6 milk reduced the concentration of myristic acid in the blood and increased the leukocytes. Milk enriched with n-3 compared to n-6 reduced the stearic acid. In conclusion, milk with a better PUFA profile can reduce saturated fatty acids in the blood and alter the concentration of cells in the defense system.

Effect of selenium and vitamin E supplementation on the metabolic status of dairy goats and respective goat kids in the peripartum period

This study aimed to examine the effects of selenium (Se) and vitamin E (vitE) supplementation on blood cell counts and blood metabolite concentrations in goats and their kids. Fifteen Saanen goats (average age 6 years of age; average initial body weight of 70 ± 10 kg) and 21 ½ Saanen × ½ Pardo Alpine crossbred goat kids (average body weight of 3.70 ± 0.64 kg) were used. Animals were distributed in a completely randomized design with five replicates per diet for mother goats and seven for goat kids and randomly assigned into three groups in the following diets: CON, control basal diet; Se, inclusion of 3.2 mg of Se/kg DM; SevitE, inclusion of 3.2 mg Se/kg DM and 1145 IU/day vitE/kg DM. Effects of time were observed on red blood cells, hemoglobin, hematocrit, mean corpuscular volume, and mean corpuscular hemoglobin in goats and goat kids. Effects of time were observed on differential counts of leucocytes, lymphocytes, and monocytes in goat kids. Interaction was observed for high-density lipoprotein and total protein in goats and for triglycerides, beta-hydroxybutyrate (BHBA), and gamma-glutamyltransferase (GGT) in goat kids. Effects of time were observed on low-density lipoprotein, triglycerides, glucose, lactate, BHBA, non-esterified fatty acids (NEFA), creatinine, aspartate-aminotransferase, and GGT in goats and all blood metabolites in goat kids. Selenium, vitE, or association in the evaluated levels are not sufficient to change blood cell counts when supplied in diets for goats or goat kids. However, the effect of time or interaction between time and diets change the blood metabolite concentrations in the animals.

Effect of Castor and Cashew Nut Shell Oils, Selenium and Vitamin E as Antioxidants on the Health and Meat Stability of Lambs Fed a High-Concentrate Diet

Functional oils are known for their compounds with antioxidant, antimicrobial and anti-inflammatory properties, and are used in ruminant nutrition as alternatives to chemicals in order to improve performance. This study aimed to compare the influence of castor and cashew nut shell oils with pure organic selenium (hydroxy-selenomethionine) plus vitamin E, which are known and well-stablished antioxidants, on the performance traits, shelf life and microbial quality of the meat, physiological functions and oxidative stress control of lambs. Thirty-two Dorper x Santa Ines lambs (initial bodyweight of 22.42 ± 3.9 kg and 60 days of age) were submitted to a diet consisting of Cynodon dactylon hay (6%) and concentrate (94%). The animals were divided into four treatments: control, without additives; functional oils (FO), 0.50 g/kg DM of castor and cashew nut shell oils; hydroxy-selenomethionine and vitamin E (SeE), 0.50 mg/kg of organic selenium and 100 IU/kg DM of vitamin E; FO plus SeE, at the same doses as the other groups. Blood samples were collected after 1, 30 and 53 days on feed. After 54 days, the lambs were slaughtered and rumen health, carcass and meat traits, shelf life, and microbiological quality were evaluated. There were no differences in performance or carcass traits. A higher muscle and serum Se concentration (p < 0.0001), lower lipid peroxidation in meat during display (p < 0.0001), and a lower count of psychrotrophic microorganisms on day 5 were observed in the SeE and FO plus SeE groups. The treatments reduced the counts of Enterobacteriaceae, and Staphylococcus spp. FO animals showed higher GSH-Px activity on day 30, while the peroxidase activity was higher in FO plus SeE animals (p = 0.035). SeE and FO plus SeE animals had lower serum ALT and AST levels. Functional oils improved the microbiological quality of meat. Hydroxy-selenomethionine and vitamin E prevented oxidative stress, lipid peroxidation, and microbial spoilage.

First isolation and whole-genome sequencing of a Shewanella algae strain from a swine farm in Brazil

BACKGROUND

Infections caused by Shewanella spp. have been increasingly reported worldwide. The advances in genomic sciences have enabled better understanding about the taxonomy and epidemiology of this agent. However, the scarcity of DNA sequencing data is still an obstacle for understanding the genus and its association with infections in humans and animals.

RESULTS

In this study, we report the first isolation and whole-genome sequencing of a Shewanella algae strain from a swine farm in Brazil using the boot sock method, as well as the resistance profile of this strain to antimicrobials. The isolate was first identified as Shewanella putrefaciens, but after whole-genome sequencing it showed greater similarity with Shewanella algae. The strain showed resistance to 46.7% of the antimicrobials tested, and 26 resistance genes were identified in the genome.

CONCLUSIONS

This report supports research made with Shewanella spp. and gives a step forward for understanding its taxonomy and epidemiology. It also highlights the risk of emerging pathogens with high resistance to antimicrobial formulas that are important to public health.

Comparative genomic survey of Bacillus cereus sensu stricto isolates from the dairy production chain in Brazil

The genomes of 262 Bacillus cereus isolates were analyzed including 69 isolates sampled from equipment, raw milk and dairy products from Brazil. The population structure of isolates showed strains belonging to known phylogenetic groups II, III, IV, V and VI. Almost all the isolates obtained from dairy products belonged to group III. Investigation of specific alleles revealed high numbers of isolates carrying toxin-associated genes including cytK (53.62%), hblA (59.42%), hblC (44.93%), hblD (53.62%), nheA (84.06%), nheB (89.86%) and nheC (84.06%) with isolates belonging to groups IV and V having significant higher prevalence of hblACD and group IV of CytK genes. Strains from dairy products had significantly lower prevalence of CytK and hblACD genes compared to isolates from equipment and raw milk/bulk tanks. Genes related to sucrose metabolism were detected at higher frequency in isolates obtained from raw milk compared to strains from equipment and utensils. The population genomic analysis demonstrated the diversity of strains and variability of putative function among B. cereus group isolates in Brazilian dairy production, with large numbers of strains potentially able to cause foodborne illness. This detailed information will contribute to targeted interventions to reduce milk contamination and spoilage associated with B. cereus in Brazil.

Efficiency of Different Disinfectants on Bacillus cereus Sensu Stricto Biofilms on Stainless-Steel Surfaces in Contact With Milk

The species of the Bacillus cereus group have the ability to adhere to and form biofilms on solid surfaces, including stainless steel, a material widely used in food industries. Biofilms allow for recontamination during food processing, and the "clean-in-place" (CIP) system is largely used by industries to control them. This study thus proposes to evaluate the efficacy of peracetic acid and sodium hypochlorite against biofilms induced on stainless-steel surfaces. The SAMN07414939 isolate (BioProject PRJNA390851), a recognized biofilm producer, was selected for biofilm induction on AISI 304 stainless steel. Biofilm induction was performed and classified into three categories: TCP (Tindalized, Contaminated, and Pasteurized milk), TCS (Tindalized milk Contaminated with Spores), and TCV (Tindalized milk Contaminated with Vegetative cells). Subsequently, the coupons were sanitized simulating a CIP procedure, on a pilot scale, using alkaline and acid solutions followed by disinfectants (peracetic acid and sodium hypochlorite). Microorganism adhesion on the surfaces reached 6.3 × 105 to 3.1 × 107 CFU/cm-2. Results did not show significant differences (p > 0.05) for surface adhesion between the three tested categories (TCP, TCS, and TCV) or (p > 0.05) between the two disinfectants (peracetic acid and sodium hypochlorite). Microbial populations adhered to the stainless-steel coupons are equally reduced after treatment with peracetic acid and sodium hypochlorite, with no differences in the control of B. cereus s.s. biofilms on AISI 304 stainless-steel surfaces.

Bacillus cereus group: genetic aspects related to food safety and dairy processing

ABSTRACT: Bacillus cereus group includes not pathogenic and high pathogenic species. They are considered as a risk to public health due to foodborne diseases and as an important cause of economic losses to industries due to production of spoilage enzymes. Some researches have been performed in order to assess the possible factors that contribute to put public health into risk because of consumption of food contaminated with viable cells or toxins which have complex mechanisms of production. The control of these bacteria in food is difficult because they are resistant to several processes used in industries. Thus, in this way, this review focused on highlighting the risk due to toxins production by bacteria from B. cereus group in food and the consequences for food safety and dairy industries.

Bacteria from the Bacillus cereus group as contaminants in requeijão curd cheeses and especialidade láctea tipo requeijão

ABSTRACT: This study aimed to evaluate the occurrence of Bacillus cereus group in requeijões and especialidades lácteas tipo requeijão (regular and light) and to verify if there is differences in relation to this occurrence among different categories of these products. A set of 14 (35%) lots was contaminated with this bacterial group from the 40 lots with low counts (maximum 3.1 × 10 CFU/g), and no significant difference regarding counts or presence/absence were observed among the categories of the products. It can be concluded that contamination by B. cereus group in these products is unable to consist in risk to consumers, regarding adequate refrigeration during selling. This study was the first one to report this bacteria group for these dairy products and highlights the needs of further investigations to evaluate the impact of its spoilage during shelf life.

Spatial distribution, prevalence and epidemiological risk factors of cysticercosis in cattle from state of São Paulo, Brazil, slaughtered for human consumption

This present research focused on establishing the prevalence, geospatial distribution and epidemiological risk factors for bovine cysticercosis in the state of São Paulo, Brazil, in cattle slaughtered for human comsumption. Data about the inspection of 104,180 bovine carcasses from 215 farms and from 70 municipalities were gathered between January and December of 2012. A cluster analysis was performed in order to correlate some variables: prevalence of bovine cysticercosis, total coffee harvesting area (hectares), orange producing areas (hectares) and Human Development Index. Afterwards, distribution maps were created in order to help the results interpretation. An average prevalence of 2.9% was established in the state of São Paulo during the studied period. The Administrative regions of São José do Rio Preto and Campinas had higher risk for cysticercosis (OR >1 and 95% CI >1). The cluster analysis showed a grouping (G1 cluster) of the variables: prevalence of bovine cysticercosis, total area of sugar cane harvested, total area of orange harvested and total area of coffee harvested. This agrroupment allows us to infer that cyticercosis cases in this region are correlated with those variables distribution. Such aspects indicate that the presence of temporary rural workers and other socioeconomic and cultural features in each region can contribute to bovine cysticercosis dissemination in some areas.

Spatial analysis of bovine cysticercosis in the state of Mato Grosso do Sul, Brazil - The needs of interventions in animal and human populations

The Taenia saginata-cysticercosis complex is an important zoonosis for public health and an important cause of economical losses for beef supply chain in developing and industrialized countries. Despite some risk factors for high-occurrence areas have already been described, further studies are required to better understand its global epidemiology. So, this study focused on establishing the prevalence, spatial distribution and environmental and human population aspects correlated with bovine cysticercosis prevalence in the state of Mato Grosso do Sul, Brazil. To this, we used data of 7,415,998 animals slaughtered from all 79 municipalities located in this state. Cysticercosis prevalence showed spatial distribution dependence (Moran Index=0.375, p=0.01) and some areas presented higher risk. Positive correlations of bovine cysticercosis prevalence with human population density (R=0.5712, p=3.85 e-08) and rainfall index (R=0.631, p=0.03) were observed. A negative correlation (R=-0.4637, p=2.096 e-05) with cattle population size was also established. These results highlight the importance of adopting sanitary measures to prevent environment contamination, besides other prophylactic measures like the treatment of human patients in order to reduce the Taenia saginata-cysticercosis complex occurrence.