Comparison among methods of effective energy evaluation of corn silage for beef cattle

Objective This study was conducted to compare different methods on effective energy evaluation of corn silage for beef cattle. Methods Twenty Wandong bulls (Chinese indigenous yellow cattle) with initial body weight of 281±15.6 kg, were assigned to 1 of 5 dietary treatments with 4 animals per treatment in a randomized complete block design. Five dietary treatments included group 1 with corn silage only diet, group 2 with corn silage-concentrate basal diet (BD) and 3 groups with 3 test diets, which were the BD partly substituted by corn silage at 10%, 30%, and 60%. The total collection digestion trial was conducted for 5 d for each block after a 10-d adaptation period, and then an open-circuit respiratory cage was used to measure the gas exchange of each animal in a consecutive 4-d period. Results The direct method-derived metabolizable energy and net energy of corn silage were 8.86 and 5.15 MJ/kg dry matter (DM), expressed as net energy requirement for maintenance and gain were 5.28 and 2.90 MJ/kg DM, respectively; the corresponding regression method-derived estimates were 8.96, 5.34, 5.37, and 2.98 MJ/kg DM, respectively. The direct method-derived estimates were not different (p>0.05) from those obtained using the regression method. Using substitution method, the nutrient apparent digestibility and effective energy values of corn silage varied with the increased corn silage substitution ratio (p<0.05). In addition, the corn silage estimates at the substitution ratio of 30% were similar to those estimated by direct and regression methods. Conclusion In determining the energy value of corn silage using substitution method, there was a discrepancy between different substitution ratios, and the substitution ratio of 30% was more appropriate than 10% or 60% in the current study. The regression method based on multiple point substitution was more appropriate than single point substitution on energy evaluation of feedstuffs for beef cattle

Robust estimation of bacterial cell count from optical density

Optical density (OD) is widely used to estimate the density of cells in liquid culture, but cannot be compared between instruments without a standardized calibration protocol and is challenging to relate to actual cell count. We address this with an interlaboratory study comparing three simple, low-cost, and highly accessible OD calibration protocols across 244 laboratories, applied to eight strains of constitutive GFP-expressing E. coli. Based on our results, we recommend calibrating OD to estimated cell count using serial dilution of silica microspheres, which produces highly precise calibration (95.5% of residuals &lt;1.2-fold), is easily assessed for quality control, also assesses instrument effective linear range, and can be combined with fluorescence calibration to obtain units of Molecules of Equivalent Fluorescein (MEFL) per cell, allowing direct comparison and data fusion with flow cytometry measurements: in our study, fluorescence per cell measurements showed only a 1.07-fold mean difference between plate reader and flow cytometry data

Comparison of two housing systems on behaviour and performance of fattening pigs

The aim of this study was to compare the effects of different housing systems on behaviour and growth performance of fattening pigs. Forty Duroc × Meishan pigs aged 100 d were assigned into two housing systems: indoor deep litter (DL) housing (4 pens with 5 pigs/pen) and indoor pen with outdoor playground (PG; 4 pens with 5 pigs/pen). Pig behaviour, body weight, and feed intake were recorded and analysed. Results showed that DL pigs spent more time exploring (DL: 231.0 vs. PG: 178.0 s/h, P < .01), while PG pigs were more aggressive (PG: 6.6 vs. DL: 0.4 s/h, P < .01) and engaged in higher levels of abnormal behaviour (PG: 20.0 vs. DL: 3.2 s/h, P < .01), specifically stereotyped behaviour and mouth-holding/biting tail. No difference was observed for the final body weight and feed conversion efficiency. The results of this study suggest that the DL system improves pig welfare at aspects of exploratory behaviour and abnormal behaviour compared with the PG housing system under the conditions studied, providing a basis for the selection and design of optimum housing systems for pigs

Differences of hormones involved in adipose metabolism and lactation between high and low producing Holstein cows during heat stress

The experiment was conducted to evaluate hormonal involvement in the adipose metabolism and lactation between high and low producing dairy cows in a hot environment. Forty Holstein healthy cows with a similar parity were used and assigned into high producing group (average production 41.44 ± 2.25 kg/d) and low producing group (average production 29.92 ± 1.02 kg/d) with 20 cows in each group. Blood samples were collected from caudal vein to determine the difference of hormones related to adipose metabolism and lactation. The highest, lowest, and average temperature humidity index (THI), recorded as 84.02, 79.35 and 81.89, respectively, indicated that cows were at the state of high heat stress. No significant differences between high and low producing groups were observed in the levels of nonestesterified fatty acid (NEFA), β-hydroxybutyrate (β-OHB), total cholesterol (TCHO), and insulin (INS) (P > 0.05). However, the very low density lipoprotein (VLDL), apolipoprotein B100 (apoB-100), high-density lipoprotein (HDL-C) and estrogen (E2) concentrations in high producing group were significantly higher than those of low producing group (P  0.05), whereas high producing group had a rise in the insulin-like growth factor-1 (IGF-1) level compared with low producing group (P < 0.05). These results indicated that, during summer, high and low producing dairy cows have similar levels of lipid catabolism, but high producing dairy cows have advantages in outputting hepatic triglyceride (TG)

MICROSTRUCTURE AND PROPERTIES OF THE CU/CNTS COMPOSITE MATERIAL

Based on the synthesis of well-distributed Cu/CNTs composite powder,Cu/CNTs composite material was prepared by spark plasma sintering（ SPS）,and the sintering temperature is 650℃,the sintering pressure is 35 Mpa,the holding time is 10 min. We studied the microstructure and properties of Cu/CNTs composite material for various content of Cu/CNTs powder. The results show that CNTs distributed uniformly along the grain boundary in copper matrix and the CNTs-Cu interface with a certain binding force is formed and the conductivity、hardness、tensile strength are 82. 8% IACS、96. 4 HV、417 MPa,and the hardness as well as tensile strength are maximum when the percent of Cu/CNTs powder is 20%

Performance evaluation of liquid catalysts for removal of mercaptan

Multi-sulfonated cobalt phthalocyanine was synthesized by the reaction of cobalt phthalocynine with chlorosulfonic acid, and then a liquid catalyst (Cat.A) with 23.8%(w) of the multi-sulfonated cobalt phthalocyanine as the active component for the removal of mercaptans from gasoline was prepared by dissolving the active component in sodium hydroxide solution with a stabilizer and an antifreezer. Cat.A was characterized by sulfur content analysis, dynamic light scattering analysis and potentiometric titration to investigate its structure, size distribution and catalytic activity, and compared with imported and domestic liquid desulfurization catalysts. The experimental results show that the average sulfonic group number in the every multi-sulfonated cobalt phthalocyanine molecule in Cat.A is 3.4. The active component in the alkali solution has good dispersity, solubility and stability. The removal rate of the mercaptans in gasoline could reach 90% using Cat.A under the conditions of the catalyst mass concentration 100 μg/g, the catalyst dosage 3 mL, gasoline with 255 μg/g of mercaptan sulfur mass concentration 30 mL, reaction temperature 30°C and reaction time 30 min

MiR-218-5p Affects Subcutaneous Adipogenesis by Targeting ACSL1, a Novel Candidate for Pig Fat Deposition

As a centre enzyme in fatty acid activation, acyl-CoA synthetase long-chain family member 1 (ACSL1) plays an important role in body lipid homeostasis. However, the functions of ACSL1 in the subcutaneous adipogenesis of pigs are largely unknown. In the present study, we found that the expression of ACSL1 significantly increased during the process of porcine preadipocyte differentiation. Moreover, silencing of ACSL1 in preadipocytes decreased levels of triglyceride and adipogenic-related markers, including FABP4, APOE, and FASN (p &lt; 0.01), and simultaneously increased levels of lipolytic-related markers, such as ATGL and HSL (p &lt; 0.05). Conversely, overexpression of ACSL1 in preadipocytes increased levels of triglyceride and FABP4, APOE, and FASN (p &lt; 0.01), and reduced levels of ATGL and HSL (p &lt; 0.05). Luciferase reporter assays revealed that ACSL1 is a target of miR-218-5p, which can reduce the mRNA and protein levels of ACSL1 by directly binding the 3&prime; untranslated region of ACSL1. Furthermore, miR-218-5p has an inhibition role in porcine preadipocyte differentiation by suppressing ACSL1 expression. Taken together, these data provide insights into the mechanism of the miR-218-5p/ACSL1 axis in regulating subcutaneous fat deposition of pigs