Transmission of pathogenic respiratory bacteria to specific pathogen free pigs at slaughter

The purpose of this study was to evaluate the transmission of pathogenic respiratory bacteria to thirteen 5-month-old specific pathogen free (SPF) pigs, during the slaughtering process in a commercial slaughterhouse. Before transportation, the SPF pigs and the lorry were checked to confirm the absence of pathogenic respiratory bacteria.

Nine SPF pigs (group 1) were in contact in a conventional slaughterhouse with finishing pigs, during 4 h before slaughtering. Four SPF pigs (group 2) were slaughtered immediately at arrival in the slaughterhouse.

Five bacterial pathogens (Mycoplasma hyopneumoniae, Actinobacillus pleuropneumoniae, Pasteurella multocida, Haemophilus parasuis and Streptococcus suis) were detected by PCR, after slaughtering, from nasal cavities, tonsils and trachea in the two groups of pigs. Lung samples were PCR negative. Three and four bacterial species were isolated from the pigs of group 2 and group 1, respectively. Cultures were negative from the lungs.

All the bacterial species present in the SPF pigs were detected by PCR. P. multocida was isolated, from three samples of scalding water before the onset of slaughtering.

Our results suggest that the SPF pigs became contaminated mainly by the slaughterhouse environment and the scalding water. Histological examinations revealed that during scalding, contaminated water could reach the trachea and the lungs of pigs. Checks conducted at slaughter for respiratory disorders have to be carried on, but nasal cavities and tonsils are not appropriate for bacteriological investigations. Moreover, bacteriological results obtained from the lungs of slaughtered pigs have to be used with carefulness.     

Optimal management of molds in stored corn

Long term storage of corn is becoming more common due to the recent increase in the demand for corn by ethanol plants. Infection of maize kernels by toxigenic fungi remains a challenging storage problem despite decades of research. Experts in storage management propose the use of a combination of preventive and monitoring-based responsive strategies in response to mold risks. In this paper, a stochastic dynamic programming model is solved to determine the expected profitability and optimal combination, timing, and intensity of the proposed mold management strategies using farmers’ existing infrastructure. The results show that even with relatively high monitoring costs, maintaining high quality grain using a monitoring-based optimal mold management strategy costs less than the benefit it fetches. The current typical practice by Indiana farmers of aerating the grain until the end of December and doing nothing thereafter bears a high risk of economic losses if grain is to be stored until later during the summer. Generally, the optimal mold management strategy depends on monitoring the biophysical conditions of the grain and the time period under consideration. If the in-bin temperature is high and less than 5% of kernels are mold damaged, then aerating when the outside temperature is at least 3 °C less than the in-bin temperature and continuing to store the grain is the optimal strategy.     

Quantification of five isoflavones and coumestrol in various solid agroenvironmental matrices using ¹³c₃-labeled internal standards

We developed and validated three different sample preparation and extraction methods followed by HPLC-MS/MS (negative electrospray ionization) analysis for the quantification of estrogenic isoflavones (formononetin, daidzein, equol, biochanin A, and genistein) and coumestrol in red clover, soil, and manure. Plant and manure samples were solid-liquid extracted, whereas soil was extracted with accelerated solvent extraction. Absolute recoveries were between 80 and 93%, 20 and 30%, and 14 and 91% for plant, soil, and manure samples, respectively. Relative recoveries ranged from 75 to 105% for all matrices, indicating that isotope-labeled internal standards (13C?-formononetin, 13C?-daidzein, 13C?-equol, 13C?-biochanin A, and 13C?-genistein) were capable to compensate for losses during analysis. The limits of detection in red clover, soil, and manure were 3-9 μg/g(dryweight(dw)), 0.6-8.2 ng/g(dw), and 34.2 ng/g(dw) to 17.0 μg/g(dw), respectively. Formononetin was the most dominant compound in red clover plants (up to 12.5 mg/g(dw)) and soil (up to 3.3 μg/g(dw)), whereas equol prevailed in manure (up to 387 μg/g(dw)).     

Tocopherol and ascorbate have contrasting effects on the viability of microencapsulated Lactobacillus rhamnosus GG

The antioxidants, sodium ascorbate and tocopherol, have contrasting effects on the viability of microencapsulated Lactobacillus rhamnosus GG (LGG) spray-dried powders during storage (4 and 25 °C; 32, 57, and 70% relative humidity). The addition of tocopherol improved probiotic viability during storage, while the incorporation of Na-ascorbate alone or in combination with tocopherol had detrimental effects on probiotic survival. The beneficial effect of tocopherol is a consequence of its chemical antioxidative action. The reduced viability in Na-ascorbate containing microcapsule formulations is hypothesized to be due primarily to the production of acetic acids arising from chemical degradation reactions and the catabolism of ascorbate by LGG. This study highlights the importance of considering the detrimental consequences of degradative chemical reactions and the metabolic fate of additives on the viability of probiotics when designing probiotic encapsulant formulations.     

A 24-Year Retrospective Study of Equine Abortion in Normandy (France)

The main causes of abortion in mares in France were studied from 1,822 cases submitted for necropsy. The cause of abortion was established in 74.9% of cases (n = 1,365). Fetoplacental infections (n = 869) represented 63.7% of diagnosed abortions. A noninfectious cause was found in 27.2% of cases (n = 496). Of the infectious causes of abortion, the vast majority were caused by bacteria (n = 695; 79.9%), followed by viruses (15.1%), and then fungi (1.8%). In 27 cases (3.1%), no specific pathogenic agent could be identified despite the presence of lesions. Of the noninfectious causes of abortion, umbilical cord abnormalities were the most frequent (n = 300; 60.5%). Placental villous hypoplasia represented the second most frequent cause (17.3%). This was followed by lethal congenital malformations (6.9%). The causes of placental insufficiency other than placental villous hypoplasia—twins, placental edema, placental premature separation, and body pregnancy—were less frequent. The diagnosis of equine abortion cases examined in Normandy seemed to be somewhat in agreement with the findings reported in Kentucky and the United Kingdom. In this study, about 60% of the cases were associated with a condition involving the allantochorion or the umbilical cord. Thus, to enhance diagnostic success, it is of prime importance to submit the fetal membranes along with the fetus for necropsy.     

Antiproliferative Properties of Scandium Exopolysaccharide Complexes on Several Cancer Cell Lines

Antimetastatic properties on both murine and human osteosarcoma cell lines (POS-1 and KHOS) have been evidenced using exopolysaccharide (EPS) derivatives, produced by Alteromonas infernus bacterium. These derivatives had no significant effect on the cell cycle neither a pro-apoptotic effect on osteosarcoma cells. Based on this observation, these EPSs could be employed as new drug delivery systems for therapeutic uses. A theranostic approach, i.e., combination of a predictive biomarker with a therapeutic agent, has been developed notably by combining with true pair of theranostic radionuclides, such as scandium ⁴⁷Sc/⁴⁴Sc. However, it is crucial to ensure that, once complexation is done, the biological properties of the vector remain intact, allowing the molecular tropism of the ligand to recognize its molecular target. It is important to assess if the biological properties of EPS evidenced on osteosarcoma cell lines remain when scandium is complexed to the polymers and can be extended to other cancer cell types. Scandium-EPS complexes were thus tested in vitro on human cell lines: MNNG/HOS osteosarcoma, A375 melanoma, A549 lung adenocarcinoma, U251 glioma, MDA231 breast cancer, and Caco2 colon cancer cells. An xCELLigence Real Cell Time Analysis (RTCA) technology assay was used to monitor for 160 h, the proliferation kinetics of the different cell lines. The tested complexes exhibited an anti-proliferative effect, this effect was more effective compared to EPS alone. This increase of the antiproliferative properties was explained by a change in conformation of EPS complexes due to their polyelectrolyte nature that was induced by complexation. Alterations of both growth factor-receptor signaling, and transmembrane protein interactions could be the principal cause of the antiproliferative effect. These results are very promising and reveal that EPS can be coupled to scandium for improving its biological effects and also suggesting that no major structural modification occurs on the ligand.     

Role of marine biology in glacial-interglacial CO2 cycles

It has been hypothesized that changes in the marine biological pump caused a major portion of the glacial reduction of atmospheric carbon dioxide by 80 to 100 parts per million through increased iron fertilization of marine plankton, increased ocean nutrient content or utilization, or shifts in dominant plankton types. We analyze sedimentary records of marine productivity at the peak and the middle of the last glacial cycle and show that neither changes in nutrient utilization in the Southern Ocean nor shifts in plankton dominance explain the CO2 drawdown. Iron fertilization and associated mechanisms can be responsible for no more than half the observed drawdown.     

Mineral nutrition of Gypsophila in vitro root culture

Mineral nutrition of panicled gypsophila roots (Gypsophila paniculata L.) (Caryophyllaceae) cultivated in vitro in two media with different mineral composition, a classical Gamborg's B5 medium and a modified MH3 medium, was studied over a growth cycle of 28 days, by continuous measurement of mineral element consumption, without opening the culture flasks. The comparison between the total mineral element quantities consumed from media and those absorbed by roots at harvesting showed a good correspondence, proving the validity of the technique used and the absence of insolubilized mineral forms in the in vitro culture media. The mineral element composition of the MH3 medium was found to be better suited to Gypsophila paniculata root culture since all mineral nutrient elements are supplied in adequate quantities which are non‐limiting and non‐excessive. Culture on B5 medium showed that phosphorus (P) and copper (Cu) are probably the factors limiting growth and revealed an ammonium (NH₄ ⁺)/potassium (K⁺) ion antagonism. The in vitro roots, although uncoupled from the aerial part, behave like the roots of whole plants in several ways: the evolution of the medium pH corresponds to the form of the mineral nitrogen (N) consumed by the roots; sodium (Na) and chloride (Cl) are barely consumed and may be considered as non‐essential elements. Lastly, this in vitro root culturemodel makes itpossible to explain that the absorption of Na and Cl by the roots of whole plants is probably dependent on the transpiratory flow of the aerial part.