 摘要： [Objective] The paper was to investigate the effects of substituting corn pellets with potato residue on the growth performance, rumen fermentation indicators and economic benefits of Xinjiang Brown cattle. [Method] A total of 80 Xinjiang Brown cattle, each 22 months old and with a similar body weight of (250±15) kg, were randomly assigned to four groups, with 20 cattle in each group, utilizing a single-factor experimental design. The total mixed diets for the experimental groups I, II, and III were formulated by substituting corn pellets with 2.00%, 4.00%, and 6.00% potato residue, respectively, while the diet in the control group was not substituted with potato residue. The duration of the test was 100 d, which comprised a pre-test period of 10 d and a formal test period of 90 d. During the test period, the average dry matter intake, average daily weight gain and feed-gain ratio were assessed at 30-day intervals, and body size indicators were measured on days 0 and 90. Rumen fluid samples were collected from the oral cavity on days 0, 30, 60, and 90 to assess rumen fermentation parameters. Additionally, jugular blood samples were obtained during the fasting period, and serum was separated for the analysis of total protein mass concentration, urea nitrogen, and glucose concentration. Furthermore, the economic benefits accrued during the test period were calculated. [Result] The dry matter intake in experimental group I was significantly higher than that in the control group from days 31 to 60 (P<0.05). In contrast, the differences in dry matter intake between experimental groups II and III and the control group were not statistically significant (P>0.05). From days 61 to 90, the dry matter intake in experimental group I remained significantly higher than that in the other groups (P<0.05). Throughout the entire experimental period, the average daily weight gain observed in experimental group I was significantly greater than that recorded in the other groups (P<0.05). Additionally, the total weight gain over the entire period was significantly higher than that of experimental group II (P<0.05) and markedly higher than that of both the control group and experimental group III (P<0.01). The feed-gain ratio in experimental group I was significantly lower than that in experimental group III (P<0.05). There were no statistically significant differences observed in body height, slope length, thoracic circumference, abdominal circumference, rumen pH, acetic acid, propionic acid, butyric acid, valeric acid, total volatile fatty acids, and ammoniacal nitrogen mass concentration among the groups (P>0.05). On the 90th day of the experiment, the serum urea nitrogen concentration in beef cattle from experimental groups I and II was significantly lower than that in the control group and experimental group III (P<0.05). Additionally, the profit margins in experimental groups I, II, and III were higher than those in the control group, and the profit margin in experimental group I was the highest. [Conclusion] The substitution of corn pellets with potato residue has the potential to enhance the average daily weight gain and total weight gain throughout the entire period in beef cattle, while simultaneously reducing the feed-gain ratio. However, this substitution does not appear to have a significant impact on body size indicators, rumen fermentation parameters, or the concentrations of serum total protein and glucose in beef cattle. Furthermore, this approach may yield improved breeding profitability, with a recommended substitution ratio of 2.00% based on the conditions of this experiment.

 摘要： [Objective] The aim of this work was to establish an analytical method for the determination of deoxynivalenol (DON) in feeds using automatic immunomagnetic beads (IMBs) clean-up coupled with high-performance liquid chromatography. [Method] Feed samples were extracted using ultra-pure water, purified by automatic IMBs, and subsequently analyzed via high-performance liquid chromatography, employing an external standard method for quantification. [Result] A satisfactory linearity was achieved for DON within the concentration range of 0.05 to 2.0 μg/mL, with the corresponding correlation coefficients (R2) exceeding 0.9999. The limit of detection (LOD) and limit of quantification (LOQ) for the proposed method were determined to be 0.03 and 0.1 mg/kg, respectively. The average recoveries of the fortified samples (0.1, 0.2 and 1.0 mg/kg) were 88.5%-100.6%, with the relative standard deviations (RSD) ranging from 2.1% to 9.7%. [Conclusion] In comparison with the traditional solid-phase extraction and immunoaffinity column purification methods, the IMBs technique consolidates the extraction, separation, and purification into a single process. This approach enables fully automated processing, which significantly enhances work efficiency and mitigates result deviations that may arise from manual operations. Consequently, this technique is particularly well-suited for the determination of DON in a large number of feed samples.

 摘要： [Objective] The study aimed to develop microecological preparations for poultry as potential substitutes for certain antibiotics. [Method] Acid-producing bacteria were isolated and purified from chicken cecal chyme, followed by evaluation of their antibacterial properties and molecular biological identification. Additionally, their in vitro tolerance and safety were experimentally assessed. [Result] A lactic acid bacterium with notable antibacterial properties was isolated and identified as Lactobacillus plantarum. This strain exhibited inhibitory effects against the pathogenic indicator bacteria Escherichia coli and Staphylococcus aureus, with maximum inhibition zone diameters measuring 8.95 and 6.43 mm, respectively. In vitro tolerance tests demonstrated that this strain was capable of growth within a pH range of 4-8, tolerated bile salt concentrations between 0.10% and 0.30%, and adapted to simulated gastric and intestinal fluid environments. Safety test revealed that the strain exhibited no hemolytic activity and was deemed safe in mouse safety assessments. [Conclusion] A chicken-derived L. plantarum strain has been identified, exhibiting notable antibacterial activity, stress tolerance, probiotic efficacy, and safety. This strain holds significant potential and market prospects for the development of microecological preparations.

 摘要： [Objective] The paper aimed to effectively reduce the occurrence of bacterial resistance associated with breeding practices and to mitigate food safety risks by controlling the illegal use of veterinary drugs in self-formulated feed at the source. [Method] A screening database comprising 274 illegally added chemical drugs in self-formulated feed was established utilizing ultra-performance liquid chromatography coupled with quadrupole/electrostatic field orbitrap high-resolution mass spectrometry (HPLC-Q-Exactive Focus/MS). Subsequently, 253 batches of self-formulated feed samples from various farms in Hebei Province were screened and quantitatively analyzed. [Result] The screening results indicated the presence of 8 pharmaceutical components across 10 batches of self-formulated feed samples, with a detection rate of 3.2% and concentrations ranging from 0.06 to 28 851.8 μg/g. [Conclusion] The application of high-resolution mass spectrometry is feasible and highly significant for the risk monitoring of illegally added drugs in self-formulated feed.

 摘要：  [Objective] The paper was to study the effects of estradiol (E2) and progesterone (P4) on the expression of interleukin-1β (IL-1β) mRNA in lipopolysaccharide (LPS)-induced acute salpingitis in ovariectomized mice, and preliminarily explore the anti-inflammatory mechanism associated with estrogen and progesterone. [Method] Healthy female KM mice were randomly assigned to several groups: the sham operation group (LPS+SHAM), the ovarian removal group (LPS+OVX), the ovarian removal + estradiol group (LPS+OVX+E2), the ovarian removal + progesterone group (LPS +OVX+P4), the LPS group and the control group (control). HE staining was conducted to assess the pathological changes in the fallopian tubes of each group. Additionally, the expression levels of IL-1β mRNA in the fallopian tubes of the mice were quantified using RT-qPCR. [Result] The histopathological changes in the fallopian tubes were examined. Estrogen and progesterone demonstrated a significant capacity to mitigate salpingitis induced by LPS. In comparison to the control group, the expression of IL-1β mRNA in the LPS group, LPS+SHAM group, and LPS+OVX+E2 group was significantly down-regulated (P<0.05). Furthermore, the expression of IL-1β mRNA in the LPS+OVX+P4 group exhibited an extremely significant down-regulation (P<0.01). When compared to the LPS+OVX group, the expression of IL-1β mRNA in the LPS+OVX+E2 group was significantly down-regulated (P<0.05), while the expression in the LPS+OVX+P4 group was extremely significantly down-regulated (P<0.01). [Conclusion] Estrogen and progesterone have the capacity to inhibit the expression of IL-1β mRNA in the inflammatory tissue of the fallopian tubes in mice, consequently diminishing the inflammatory response induced by LPS.

 摘要： [Objective] The paper was to investigate the artificial rearing of Pagiophloeus tsushimanus larvae and to propose a novel approach for addressing the challenges associated with test insects for pest research experiments. [Method] A study was conducted to investigate the effects of three semi-artificial diets on the rearing of P. tsushimanus larvae. [Result] The study revealed significant differences in the fitness performance of P. tsushimanus larvae reared on three distinct semi-artificial diets. Notably, larvae that were fed semi-artificial diets formulated from their natural host plant, Cinnamomum camphora, exhibited superior growth and developmental performance. In contrast, P. tsushimanus larvae that were provided with semi-artificial diets derived from Cinnamomum chekiangense and Phoebe chekiangensis, which are closely related species, demonstrated marked fitness costs. These costs were evidenced by a significant prolongation of the larval developmental duration, a substantial decrease in body weight and average daily weight gain, as well as a notable reduction in survival rate, pupation rate, and emergence rate. [Conclusion] Semi-artificial diets derived from the natural host plant, C. camphora, represent the most effective dietary regimen for the indoor rearing of P. tsushimanus larvae. This approach not only ensures a sufficient supply of test insects but also serves as a viable rearing method for research focused on the integrated prevention and control of P. tsushimanus.

 摘要： [Objective] The paper was to was to screen sensitive drugs and their combinations against biofilm formation of Escherichia coli strains isolated from Tibetan pigs and Tibetan chickens. [Method] Semi-quantitative modified crystal violet staining and the micro broth dilution method were employed to assess the biofilm-forming capacities of 152 E. coli strains, as well as their susceptibility to 12 commonly used antibiotics. Meanwhile, checkerboard dilution method was employed to evaluate the combined antibacterial activity of the sequential solvent fractions (methanol, dichloromethane, ethyl acetate, and petroleum ether) from four Tibetan veterinary medicinal plants (Spenceria ramalana Trimen, Thalictrum delavayi Franch., Gentiana sino-ornata Balf. f., Lonicera rupicola Hook.f. & Thomson), the ethyl acetate extract of two Enterococcus faecium strains and antibiotics with high resistance rates [chloramphenicol (CHL), oxytetracycline (OTC), ampicillin (AMP), and sulfamethoxazole (SMZ)] against ten selected multi-drug resistant E. coli strains (designated E1-E10). Lastly, the clearance effects of various drug combinations on E6 biofilms of E. coli were examined. [Result] The majority of the 152 E. coli strains exhibited moderate and no biofilm-forming capacities. The resistance rates to CHL, sulfamethazine (SM2), OTC, AMP, and SMZ exceeded 90%. In contrast, the resistance rates to difloxacin (DIF), ciprofloxacin (CIP), amikacin (AMK), ceftiofur (EFT), tobramycin (TOB), and ceftriaxone (CTR) were below 50%. Notably, these strains demonstrated a higher susceptibility to amikacin, with a drug resistance rate of only 19.90%. The MIC values for the E. coli strains E1-E10 were observed to range from 3.93 to 15.63 mg/mL for the methanol extract of S. ramalana, from 3.93 to 31.52 mg/mL for the ethyl acetate extract of T. delavayi, from 7.81 to 15.63 mg/mL for the methanol extract of G. sino-ornata, and from 7.81 to 31.52 mg/mL for the ethyl acetate extract of L. rupicola. Additionally, the ethyl acetate extracts from E. aecium strains S16 and S17 exhibited MIC values ranging from 0.42 to 13.38 mg/mL and from 0.45 to 3.63 mg/mL, respectively. The combinations of sequential solvent fractions derived from four Tibetan veterinary medicinal plants, the ethyl acetate extract of E. faecium, and antibiotics exhibiting high resistance rates demonstrated varying effects. At the MIC, all drug combinations exhibited a more pronounced biofilm clearance effect compared to their individual applications. The ethyl acetate extracts of L. rupicola and T. delavayi, when combined with OTC and AMP, demonstrated a greater inhibitory effect on the E6 biofilm compared to other combinations. Specifically, the ethyl acetate extracts of L. rupicola and T. delavayi inhibited the E6 biofilm by 48.92% and 42.58% in the presence of OTC, and by 48.58% and 47.84% in the presence of AMP, respectively. [Conclusion] The combined application of four selected Tibetan medicinal plants, probiotics, and antibacterial agents may offer a potential solution to address drug resistance and biofilm formation in E. coli isolated from Tibetan pigs and Tibetan chickens.