Evaluation of homeopathic and biotherapic treatments in a swine farm to control Escherichia coli infection: a long term study

Background: Escherichia coli is the most important etiological agent in neonatal diarrhea in swine, and Enterotoxigenic Escherichia coli (ETEC) is the most commonly isolated. Regarding to virulence factors, five main types of fimbriae were already described in swine samples: F4 (K88), F5 (K99), F6 (987P), F18 and F41. Thermolabile (LT) and thermostable enterotoxins (ST), as well as shiga-like toxin or verotoxin (Stx2) are also found in isolates of swine origin, related to diarrhoea process. Methods: This long term study has been developed in a swine farm (Mato Grosso, Brazil), in which 93 piglets were studied and 184 fecal samples were evaluated in two steps, with the aim to search the presence of Escherichia coli and to prepare a specific biotherapic medicine. Each step had one year of interval each other. Concurrently, for each step, a detailed anamnesis was made for choosing the ideal homeopathic medication for each step (Phosphorus 30 CH and Pulsatilla 30 CH, respectively). In each step, four groups consisting of 11-12 piglets and the respective primiparous mother pig were formed, and the treatments happened simultaneously: control group (antimicrobial treatment, the same used in the swine farm), homeopathic medication, E. coli biotherapic and homeopathic medication associated to biotherapic. The medications were made according to the Brazilian Homeopathic Pharmacopeia and the treatment lasted 12 days. After 24 days, in the weaning, the weight gain of each bath was also evaluated. Considering both steps, the research of virulence factors and enterotoxins was carried out in 99 Escherichia coli colonies through Polymerase Chain Reaction - PCR. Results: In both steps, the homeopathy treated groups passed from 75.0% of diarrhea incidence to 8.3% at the end of the treatment (p

Sporadic Dissemination of tet (X3) and tet (X6) Mediated by Highly Diverse Plasmidomes among Livestock-Associated Acinetobacter

Recently identified plasmid-borne tet (X) genes have greatly challenged the efficiency of tigecycline, a last-resort antibiotic for severe infection, while the dissemination pattern of the plasmid-borne tet (X) genes remains unclear. In this study, we identified a clonal dissemination of tet (X3)-positive A. towneri isolates on a swine farm, while the tet (X6)-positive A. towneri strains mainly disseminated sporadically on the same farm.

Global dissemination of tet(X3) and tet(X6) among livestock-associated Acinetobacter is sporadically mediated by highly diverse plasmidomes

The emergence of plasmid-borne tet(X) genes mediates high-level resistance of tigecycline largely threatening its clinical effectiveness. Currently, the dissemination pattern of plasmid-borne tet(X) genes remains unclear. In this study, 684 fecal and environmental samples were collected at six livestock farms, and 15 tet(X)-positive Acinetobacter isolates were recovered, mainly including 9 tet(X3)- and 5 tet(X6)-positive A. towneri strains. A clonal dissemination of tet(X3)-positive A. towneri was detected in a swine farm, while the tet(X6)-positive A. towneri strains mainly sporadically disseminated in the same farm. A tet(X3)-carrying plasmid (pAT181) was self-transmissible from a tigecycline-susceptible A. towneri strain to A. baumannii ATCC17978, causing a 128-fold and 64-512-fold increase in the MIC values of tigecycline and the other tetracyclines, respectively. Worrisomely, pAT181 was stably maintained and increased the growth rate of ATCC17978. Further identification of tet(X)s in 10,680 Acinetobacter genomes retrieved from GenBank revealed that, tet(X3) (n=249) followed by tet(X5)-like (n=61) and tet(X6) (n=53) are the prevalent alleles mainly carried by four species, and most of them are livestock associated. Phylogenetic analysis showed that most of tet(X3) and tet(X6)-positive isolates disseminate sporadically. The structures of tet(X3) and tet(X6) plasmidomes are highly diverse and no epidemic plasmids have emerged yet. However, cross-species and cross-region transmissions of tet(X3) might have been mediated by several plasmids in a small proportion of strains. Our study evidence that tet(X3) and tet(X6) currently disseminate sporadically in Acinetobacter. Continuous surveillance for tet(X)s in the context of One Health is necessary to prevent them from transmitting to humans.

Airborne Spread of Methicillin Resistant Staphylococcus aureus From a Swine Farm

Spread of livestock-associated methicillin resistant Staphylococcus aureus (LA-MRSA) to farmworkers has been recognized as a risk when working in LA-MRSA positive stables, due to LA-MRSA being present on airborne dust particles. Based on this, airborne spread of LA-MRSA through stable vents is a concern that is addressed in this study. The aim of the investigation was to quantify the airborne spread of LA-MRSA from a MRSA positive swine farm. In order to achieve this, a method for sampling large volumes of air was applied. The results were compared to meteorological data and bacteriological investigation of samples from the air inside the swine barn, soil outside the farm, and nasal samples from the individuals participating in the sampling process. MRSA was detected up to 300 m (the maximal measuring distance) from the swine farm in the air but only at low levels at distances above 50 meters (0.085 CFU/m3 at a distance of 50 m in the wind plume). MRSA was detected in sock samples obtained at the soil surfaces up to 400 m (the maximal measuring distance) from the farm building. The proportion of MRSA positive soil samples decreased from ~80 to 30% with increasing distance from the farm. A total of 25 human nasal samples were sampled after the farm visits after the participants had stayed in the surroundings of the farm for an average of 10.5 h. When leaving the farm, only two of the samples (8%) were LA-MRSA-positive both obtained from one individual who was the one who had sampled the ventilation shafts. In conclusion, airborne spread of MRSA from swine farms does not seem to be an important route for human contamination for individuals staying a whole working day outside a swine farm.

Complete Coding Genome Sequence of a Novel Porcine Reproductive and Respiratory Syndrome Virus 2 Restriction Fragment Length Polymorphism 1-4-4 Lineage 1C Variant Identified in Iowa, USA

A porcine reproductive and respiratory syndrome virus 2 strain was identified in lung samples from nursery piglets associated with a 17.15% mortality rate on a swine farm in Iowa, USA. Open reading frame 5 (ORF5) sequencing indicated that this strain is a restriction fragment length polymorphism (RFLP) 1-4-4 lineage 1C variant strain, and its complete coding genome sequence was determined.

54 Relationships Between Heat Stress and Behavioral Responses with Reproductive Traits of Maternal-line Gilts

Heat stress (HS) during summer months can negatively affect reproductive efficiency and sow productivity. This study was designed to evaluate potential relationships between HS sensitivity and behavior with litter characteristics in replacement gilts. A total of 61 replacement gilts (108.8± 10.4 kg BW; 8 repetitions; 9d/repetition), were tested from February to May 2020 at the USDA-ARS Food Animal Behavior Laboratory in West Lafayette, IN. Pigs were housed (2/pen) in thermoneutral (TN; 22.6± 1.6⁰C) conditions and their behavior was recorded for 5 d. On d 6, gilts were subjected to an open field test and novel object test. Heart rate, number of escape attempts, and vocalizations were recorded during behavior testing. Vaginal temperature monitors were inserted to record body temperature (TB) every 15 min. Gilts were individually housed and exposed to cyclic HS (28.2± 0.97⁰C nighttime to 36.9± 1.9⁰C daytime; 46± 15.4% relative humidity) on d 7 to 9. Feed was provided ad libitum and feed intake was recorded daily. During the HS challenge, respiration rate (RR), skin (ear, shoulder, rump, and tail) temperature, and posture were recorded every 2 h from 0800 to 2000 h. Following the HS challenge, gilts were transported to the Purdue University swine farm, and gilts that displayed signs of estrus were artificially inseminated (253±29 d of age) between May and September 2020. At farrowing, litter characteristics were obtained and included total number of piglets born, total number of piglets born alive, average litter birth weight, total number of piglets weaned, and average weaning weight of the litter. Correlations between behavior, HS response, and litter characteristics were obtained using JMP 15 software. The preliminary analysis indicated no significant interactions (P < 0.05) between RR or TB with litter characteristics. However additional records are currently being collected, which might reveal important trends among the traits analyzed.

Mitigation of Odor and Gaseous Emissions from Swine Barn with UV-A and UV-C Photocatalysis

UV-A (ca. 365 nm wavelength, a.k.a. ‘black light’) photocatalysis has been investigated to comprehensively mitigate odor and selected air pollutants in the livestock environment. This study was conducted to confirm the performance of UV-A photocatalysis on the swine farm. The objectives of this research were to (1) scale-up of the UV-A photocatalysis treatment, (2) evaluate the mitigation of odorous gases from swine slurry pit, (3) test different UV sources, (4) evaluate the effect of particulate matter (PM) and (5) conduct preliminary economic analyses. We tested UV-A photocatalysis at a mobile laboratory-scale capable of treating ~0.2–0.8 m3·s−1 of barn exhaust air. The targeted gaseous emissions of barn exhaust air were significantly mitigated (p < 0.05) up to 40% reduction of measured odor; 63%, 44%, 32%, 40%, 66% and 49% reduction of dimethyl disulfide, isobutyric acid, butanoic acid, p-cresol, indole and skatole, respectively; 40% reduction of H2S; 100% reduction of O3; and 13% reduction of N2O. The PM mitigation effect was not significant. Formaldehyde levels did not change, and a 21% generation of CO2 was observed. The percent reduction of targeted gases decreased as the airborne PM increased. Simultaneous chemical and sensory analysis confirmed that UV-A treatment changed the overall nuisance odor character of swine barn emissions into weaker manure odor with ‘toothpaste and ‘mint’ notes. The smell of benzoic acid generated in UV-A treatment was likely one of the compounds responsible for the less-offensive overall odor character of the UV-treated emissions. Results are needed to inform the design of a farm-scale trial, where the interior barn walls can be treated with the photocatalyst.

Can portable analyzers be reliable for biogas characterization?

Anaerobic digestion for treatment of swine wastewater is an attractive alternative, among other aspects, for the generation of biogas. This gas is composed predominantly of methane and can be converted into electrical and thermal energy. However, the knowledge of the biogas composition is of paramount importance, especially regarding the methane content due to its energetic properties. The alternatives for this determination usually require high cost and specialized technicians. Therefore, the search for simple and low cost alternative solutions and techniques can improve the biogas use as an energy source and favor energy sustainability in pig farming. The present study aimed to compare the results of the methane composition of a portable analyzer with that of a Gasboard gas analyzer. The biogas was collected and characterized in a full cycle swine farm from January to December 2019 in the municipality of Teixeiras (MG), Brazil. The methane composition values did not differ statistically for a 5% significance level between the evaluated methods. The use of the portable kit is a simple and low cost alternative in determining the methane content in biogas and can be used reliably.