Determining the Phosphorus Release Curve for Sunphase HT Phytase from 250 to 2,000 FTU/kg in Nursery Pig Diets

A total of 280 pigs (DNA 241 × 600; initially 22.9 ± 0.52 lb BW) were used in a 21-d growth study to determine the available P (aP) release curve for Sunphase HT phytase (Wuhan Sunhy Biology Co., Ltd.; Wuhan, P.R. China). At approximately 19 d of age, pigs were weaned, randomly allotted to pens, and fed common starter diets. Pigs were blocked by average pen body weight (BW) and randomly allotted to 1 of 7 dietary treatments on d 21 post-weaning, considered d 0 of the study. Dietary treatments were derived from a single basal diet, and ingredients including phytase, monocalcium P, limestone, and sand were added to create the treatment diets. Treatments included 3 diets containing increasing (0.11, 0.19, and 0.27% aP) inorganic P from monocalcium P, or 4 diets with increasing phytase (250, 500, 1,000, or 2,000 FTU/kg) added to the diet containing 0.11% aP. All diets were corn-soybean meal-canola meal-based and were formulated to contain 1.24% SID Lys and an analyzed Ca:P ratio of 1.10:1. Prior to the beginning of the study, all pigs were fed a diet containing 0.11% aP for a 3-d period (d 18 to 21 post-weaning). At the conclusion of the study, 1 pig, closest to the mean weight of each pen, was euthanized and the right fibula, rib, and metacarpal were collected to determine bone ash and density. For the overall experimental period, pigs fed increasing levels of aP from inorganic P had improved (linear, P ≤ 0.014) ADG, F/G, and final BW. Similarly, pigs fed increasing phytase had increased (linear, P ≤ 0.011) ADG and final BW as well as improved (quadratic, P = 0.017) F/G. For fibula bone ash weight and percentage bone ash, rib bone ash weight and bone density, and all metacarpal bone properties, pigs fed increasing levels of aP from inorganic P exhibited a linear improvement (P ≤ 0.019), with a quadratic response (P ≤ 0.030) for fibula bone density and rib percentage bone ash. Additionally, pigs fed increasing phytase had increased (P \u3c 0.05) bone ash weight, percentage bone ash, and bone density in either a linear or quadratic fashion depending on the bone analyzed. The available P release curve generated for Sunphase HT for percentage bone ash combining values from right fibula, rib, and metacarpal is: aP = (0.360 × FTU) ÷ (2,330.250 + FTU)

Response of Freshwater Biofilms to Antibiotic Florfenicol and Ofloxacin Stress: Role of Extracellular Polymeric Substances

Antibiotic residues have been detected in aquatic environments worldwide. Biofilms are one of the most successful life forms, and as a result are ubiquitous in natural waters. However, the response mechanism of freshwater biofilms to the stress of various antibiotic residues is still unclear. Here, the stress of veterinary antibiotic florfenicol (FF) and fluoroquinolone antibiotic ofloxacin (OFL) on freshwater biofilms were investigated by determining the changes in the key physicochemical and biological properties of the biofilms. The results showed that the chlorophyll a content in biofilms firstly decreased to 46⁻71% and then recovered to original content under the stress of FF and OFL with high, mid, and low concentrations. Meanwhile, the activities of antioxidant enzymes, including superoxide dismutase and catalase, increased between 1.3⁻6.7 times their initial values. FF was more toxic to the biofilms than OFL. The distribution coefficients of FF and OFL binding in extracellular polymeric substances (EPS)-free biofilms were 3.2 and 6.5 times higher than those in intact biofilms, respectively. It indicated that EPS could inhibit the FF and OFL accumulation in biofilm cells. The present study shows that the EPS matrix, as the house of freshwater biofilms, is the primary barrier that resists the stress from antibiotic residues

Incidence of Lower Limb Deep Venous Thrombosis and Coagulation Status in Severe Patients after Thoracic Surgery

Background and objective The aim of this study was to analyze the incidence of lower limb deep venous thrombosis (DVT) and the corresponding coagulation status in severe patients after thoracic surgery. Methods Severe patients after thoracic surgery who received mechanical prophylaxis of lower limb DVT between July 2016 and June 2018 were analysed retrospectively. Their general information, disease species, surgical treatment, and coagulation index were reviewed. Results Fifty patients were finally included. There were 34 male and 16 female, aging from 22 to 80 years. The incidence of DVT was 22.0%, all of them were isolated calf DVT. The incidence was 29.4% in male patients, while 6.3% in female; 23.5% in malignant diseases and 18.6% in benign. All coagulation index presented no statistical difference between patients with and without DVT, except activated partial thromboplastin time (APTT). Conclusion Even on the basis of adequate mechanical prophylaxis, lower limb DVT is common in severe patients after thoracic surgery. Meanwhile, male patients and malignant diseases are more suscepted