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Toxoplasma gondii is a worldwide-distributed zoonotic protozoan parasite which causes toxoplasmosis and has a significant effect on public health. In the giant panda (Ailuropoda melanoleuca), toxoplasmosis can cause asymptomatic infections, reproductive disorder and even death, which poses a serious threat to the conservation of this rare protected species. Therefore, serological investigation of T. gondii is essential to understanding its risk to giant pandas, however, there are no specific testing kits for giant pandas. Previous research has used MAT as the reference method for screening T. gondii , to investigate this further, this study focused on the agreement comparing of MAT with ELISA and IHA tests for detecting T. gondii antibodies in 100 blood samples from 55 captive giant pandas in Chengdu, China. The results showed 87.0%, 87.0%, 84.0%, samples were sero-positive for T. gondii using ELISA (kits a, b, c), respectively, while MAT and IHA tests were 84.0% and 9.0% sero-positive, respectively. There was no significant difference between MAT and the three ELISA kits and these two methods had substantial agreement (0.61 < қ ≤ 0.80). Meanwhile, there was a significant difference (P < 0.001) between MAT and IHA, and these two methods had only a slight agreement (қ ≤ 0.20). The relative sensitivity of the ELISA (kits a, b, c) were 89.0%, 91.5% and 95.1%, and the specificity were 86.7%, 80.0% and 80.0%, respectively, which showed these three ELISA kits all had great accuracy. It is suggested that MAT is the recommended test method for primary screening T. gondii in giant pandas and then verified by ELISA. [Display omitted] • It's the first report to compare the agreement of the three test kits for detecting T. gondii antibodies in giant panda. • No significant difference and substantial agreement between MAT and ELISA, slight agreement, meanwhile, the contrary result between MAT and IHA. • The relative sensitivity of ELISA kits was 89%, 91.5% and 95.1%, and the specificity was 86.7%, 80% and 80%, respectively. • The two commonly used commercial MAT and ELISA kits tested were valuable tools for T. gondii diagnosis for giant panda. [ABSTRACT FROM AUTHOR]

Airborne bacteria and particulate matter (PM) emitted from animal houses may harm the environment and threaten on-farm and off-farm bio-security. Airborne transmission of PM and bacteria occurs more easily between double-tunnel ventilation layer hen houses with side-to-side arrangement due to the layout of inlet and outlet, and the accumulation of airborne contaminants in the intermediate region. This study practically applied shading nets for covering exhaust area and water disinfection for evaporative cooling system to prevent airborne transmission of PM and microbial aerosols between layer hen houses. Differences of PM and airborne culturable bacteria (CB) concentrations in control group and experimental group were used to evaluate the contaminants blocking effect of the treatment. PM and airborne microbial concentrations between houses were significantly higher than the upwind. Shading nets used as a barrier of PM and airborne bacteria had no significant effect on the reduction of inlet PM and airborne CB concentration of layer hen houses. The airborne CB concentration after evaporative cooling pads with water could be several times higher than that before. However, airborne CB concentration after the evaporative cooling pads with water disinfection was much lower than that before. Results indicated that shading net as a barrier of PM and airborne bacteria could hardly bring down contaminants concentrations near the inlet. Water disinfection for evaporative cooling system could largely reduce the inlet airborne CB concentration. Inlet air purification of animal houses is an effective way to prevent airborne microorganisms transmission. [ABSTRACT FROM AUTHOR]

Renal cell carcinoma (RCC) is the most common subtype of kidney cancer. Currently, there is a lack of efficient treatment for RCC. Bicyclol, an anti-hepatitis drug, has been demonstrated to possess anti-tumor properties. However, the effect of bicyclol in RCC remains elusive. Therefore, the aim of this study is to investigate the biological effects of bicyclol on RCC and the underlying mechanisms. The data from this study indicated that bicyclol markedly induced cell apoptosis and cell cycle arrest and increased the production of reactive oxygen species (ROS) in RCC cells. Moreover, bicyclol induced ER stress in a ROS-dependent manner, since the ROS scavenger NAC could block this effect. Taken together, the results of this study provide evidence that bicyclol may serve as a potential therapeutic agent for the treatment of human RCC. [ABSTRACT FROM AUTHOR]

Light is one of the essential environmental factors in the production process of laying hens, which can directly affect their behavior, growth and development, and production performance. The spectral sensitivity of humans is different from that of poultry, and the perceived illuminance units of human and poultry are lux and clux, respectively. If the light management of laying hen production is carried out according to human perceived illuminance, the growth and development of laying hens during pullet rearing may be adversely affected due to the discomfort of the perceived illuminance. Preliminary research has found that blue-green LED light can improve the immune function of laying hens during the brooding and rearing periods. However, the differences of the effects caused by blue-green light on the immune performance and bone development of laying hens during pullet rearing are still unclear for the 2 spectral sensitivities. A total of 120 Jinghong layer chickens were raised from 1 d to 13 wk of age in one of three groups with a white LED light (light intensity unit lux, WL) group, a blue-green LED light (light intensity unit lux, HBGL) group, and blue-green LED light (light intensity unit clux, PBGL) group, and unlimited feed and water were provided during the whole experiment. At 7 and 13 wk of age, the immune performance, bone parameters, and related gene expression were investigated. The results showed that compared with the WL groups, HBGL and PBGL increased the immunoglobulin A (IgA) content at 13 wk of age and the IgM content at 7 wk of age (P < 0.05). The bone mineral density (BMD) at 7 and 13 wk of age and tibial strength (TS) at 13 wk of age of the pullets in the WL group were significantly higher than those in the HBGL and PBGL group (P < 0.05). Osteoclastogenesis inhibitory factor gene (OPG mRNA) expression was increased in the layer chickens at the age of 7 and 13 wk for the WL group (P < 0.05). Compared with the WL group and PBGL group, the melanopsin gene (OPN4 mRNA) transcription level of hypothalamus and pineal gland of the chickens under HBGL significantly increased at 7 and 13 wk of age (P < 0.05). In conclusion, blue-green LED light with two perceived illuminance (human and poultry) can increase the Ig content and the immune performance of layer chickens, and blue-green LED light (light intensity unit lux) can promote the expression of OPN4 gene in the hypothalamus and pineal gland. In addition, white LED light can enhance bone quality by increasing tibia OPG gene expression. [ABSTRACT FROM AUTHOR]

• High-level CO 2 concentration was used during the early and late incubation. • Upregulation of CO 2 concentration shortened hatching time and hatch window. • Combined CO 2 regulation do not affect hatchability and hatchling quality. • Combined high-level CO 2 changes chicken embryo hormone levels and nutrient metabolism. • High-level CO 2 during incubation can be saving energy and improving animal welfare. Carbon dioxide (CO 2) is always maintained at ambient levels by ventilation in commercial egg incubators. However, elevated CO 2 levels during the early and late periods have been reported to improve the quality of chicks and shorten the hatch window. This study investigated the effect of precise CO 2 supplementation during the early and late periods of incubation on embryo growth and incubation performance by developing and using a CO 2 supplementation system to increase the CO 2 level in an experimental egg incubator. The CO 2 level was maintained at 1% in the early period (from the beginning to the 10th day of incubation, E0 – E10) and in the late period (from internal pipping (IP) to the 21st day of incubation (E21), IP–E21) in an incubator for the treatment group, whereas the CO 2 level was maintained at the ambient level in the other incubators for the control group. A comparative assessment of embryonic development, hatching characteristics, and hormone and nutrient levels was conducted for each trial. The experiment comprised three trials, with 300 Jing Hong No. 1 breeding eggs in each incubator. The elevated CO 2 treatment significantly shortened the chick hatching time (H0) by 4 h (P < 0.05) and the hatch window by 3 h (P < 0.05) without affecting hatchability, chick weight at 1 d of age, brooding period, or quality score. At external pipping (EP), the heart weight, intestinal weight, relative intestinal weight, and relative heart weight in the treatment group were significantly higher than those in the control group (P < 0.05). In addition, the embryonic intestine, relative intestine, and relative heart weights of the newly hatched chicks in the treatment group were significantly higher than those in the control group (P < 0.05) at H0. The treatment significantly increased the concentration of corticosterone in the embryonic plasma during the period from IP to EP (P < 0.05), promoted the secretion of triiodothyronine and tetraiodothyronine (P < 0.05), and increased the glycogen content of the embryonic liver on E21 (P < 0.05). This result indicates that elevated CO 2 (1%) during the early and late periods of incubation accelerated embryonic organ development and shortened the chick hatching time and hatch window without affecting hatchability or hatchling quality, which can be explained by the synergistic functions of the secretion of plasma corticosterone and thyroid hormones and the accumulation of liver glycogen between the early and late periods of incubation. [ABSTRACT FROM AUTHOR]

Conventional chemical disinfectants used for egg disinfection could result in toxic residue and endanger hatchability, chick quality, and pullet growth performance. Slightly acidic electrolyzed water (SAEW) is known as a novel disinfectant for egg sterilization due to its high efficiency and no residue. In this study, a comprehensive assessment of slightly acidic electrolyzed water and benzalkonium bromide solution (BBS) used in the disinfection channel was conducted to assess the microbial count, eggshell quality, and hatchability concomitantly. The results show that the sterilization efficiency of SAEW increased with an increase in available chlorine concentration (ACC), spraying volume, and sterilization duration. SAEW with an ACC of 150 mg/L and 10,000 mg/L benzalkonium bromide solution had the same sterilization rates of approximately 86.2% at a spraying volume of 0.5 mL/egg and sterilization duration of 180 s. Neither had significant effect on eggshell strength or thickness. The eggshell cuticle quality in the benzalkonium bromide group was significantly higher than the control group (no disinfection) and the 150 mg/L SAEW group. The embryo weight, relative embryo weight, hatchability, and embryonic mortality in the SAEW group had no significant differences of those in the benzalkonium bromide group. SAEW should be more popular because of its simple preparation, low cost, and no residue. Our results indicate SAEW is an alternative disinfectant for the sterilization of hatching eggs instead of conventional chemical disinfectants, such as benzalkonium bromide, and give a recommendation is using SAEW as a disinfectant with 150 mg/L ACC, 0.5 mL/egg spray volume, and disinfection for 180 s in the novel disinfection channel. [ABSTRACT FROM AUTHOR]

• PM and airborne bacteria were monitored based on respiratory tract deposition. • The quantitative relationship between PM and airborne bacteria was established. • Particles with diameters of 2.1–4.7 μm carry the most airborne bacteria in CAFOs. Bacterial loading aggravates the health and environmental hazards of particulate matter (PM), particularly in concentrated animal feeding operations. Understanding the association between PM and airborne bacteria is conducive to accurately assessing occupational exposure, providing fundamental data for exposure mitigation via engineering solutions, and providing information regarding the physical properties influencing the transmission of airborne microorganisms at emission sources. In this work, we conducted a joint study to systematically determine the concentrations and size distributions of PM and airborne bacteria, and establish the quantitative relationship between PM and airborne bacteria in laying hen houses. The association between PM and airborne bacteria was expressed as the load of airborne bacteria on PM in terms of the identical particle size interval based on the size-resolved respiratory tract deposition. The concentrations and size distributions of PM and airborne bacteria in laying hen houses were affected by the in-house space (upper and lower), chicken activity (day and night), and outside temperature. The size distributions of PM and airborne bacteria indicated that the mass concentration of large particles decreased with increasing outside temperature, while the concentration of airborne bacteria loaded on the small particles increased with increasing outside temperature. The results indicated that particles with diameters ranging from 2.1 to 4.7 μm carried the most airborne bacteria. Therefore, particles with diameters ranging from 2.1 to 4.7 μm should be the focus of future experimental research on occupational exposure, air quality improvement, and the airborne transmission of PM and airborne microorganisms originating from concentrated layer feeding operations. [ABSTRACT FROM AUTHOR]

Disease transmission across built environments has been found to be a serious health risk. Airborne transmission is a vital route of disease infection caused by bacteria and virus. However, tracing methods of airborne bacteria in both lab and field research failed to veritably express the transporting process of microorganism in the air. A new tracing method of airborne bacteria used for airborne transmission was put forward and demonstrated its feasibility by conducting a field evaluation on the basis of genetic modification and bioaerosol technology. A specific gene fragment (pFPV-mCherry fluorescent protein plasmid) was introduced into nonpathogenic E. coli DH5α as tracer bacteria by high-voltage electroporation. Gel electrophoresis and DNA sequencing proved the success of the synthesis. Genetic stability, effect of aerosolization on the survival rate of tracer bacteria, and the application of the tracer bacteria to the airborne bacteria transmission were examined in both lab and field. Both the introduced plasmid stability rates of tracer E. coli in pre-aerosolization and post-aerosolization were above 95% in five test days. Survival rate of tracer E. coli at 97.5% ± 1.2% through aerosolization was obtained by an air-atomizer operated at an air pressure of 30 Psi. In the field experiment, the airborne transmission of E. coli between poultry houses was proved and emitted E. coli was more easily transmitted into self-house than adjacent house due to the ventilation design and weather condition. Our results suggested that the tracing method of airborne bacteria was available for the investigation of airborne microbial transmission across built environments. • Both physical and biological characteristics of airborne bacteria were considered. • Field validation was conducted between animal houses and proved it feasible. • Airborne E. coli could be transmitted between adjacent animal buildings. • Relative biological decay is promising in the validation of disease transport model. [ABSTRACT FROM AUTHOR]

Slightly acidic electrolyzed water (SAEW) is well-known for its highly potent antibacterial properties and safe residue-free nature. In this study, a comprehensive evaluation was conducted on 2 disinfection methods for waterline cleaning in poultry houses: (1) continuously add SAEW into the waterline and (2) the conventional waterline disinfection method, which includes regular use of high-concentration chemical disinfectant for soaking the waterline and flushing with water. The evaluation focused on the effects of these methods on bacteria levels in laying hens' drinking water, the fecal normal rate of laying hens, egg quality, as well as the economic costs and water footprint associated with each method. The results show that the inhibition rate of the control group was 52.45% to 80.36%, which used 1500 mg/L sodium dichloroisocyanurate (DCCNa) for soaking and then flushing with water. The bacterial levels in the waterline returned to pre-treatment levels 26 h after cleaning. However, the experimental group with an available chlorine concentration (ACC) of 0.3 mg/L SAEW showed a higher inhibition rate (99.90%) than the control group (P < 0.05) and exhibited a sustained antimicrobial effect. Regarding eggshell thickness, eggshell strength, and Haugh units of the egg, there were no significant differences between the experimental and control groups. However, the experimental group had higher egg weight and darker yolk color (P < 0.05) than those of the control group. Besides, the experimental group exhibited a higher fecal normal rate and a lower water footprint than those of the control group. Hence, SAEW represents a favorable choice for disinfecting drinking water in poultry houses due to its ease of preparation, lack of residue, energy efficiency, and efficient antibacterial properties. To ensure adequate sanitation, it is recommended to incorporate SAEW with an ACC of 0.3 mg/L into the daily management of the drinking water system for laying hens. [ABSTRACT FROM AUTHOR]

Major limitations of chalcones as clinical anticancer agents are water insolubility and poor bioavailability, which may be improved by a classic phosphate prodrug strategy that targets non-specific alkaline phosphatase (ALP) for releasing the parent drug in vivo . In this study, we found that BOC26P , a phosphate prodrug of chalcone OC26 , exhibits excellent water solubility and improved plasma concentration in vivo by either i.v. or p.o. compared with the parent drug. In pace with decreased inhibitory activity of BOC26P against microtubule polymerization in vitro and in cells, the antiproliferative activity of BOC26P is attenuated in A549 and HLF cells. However, the antitumor effect of BOC26P increases in an A549 xenograft model as compared to the equimolar concentration of OC26 , suggesting that complex tumor microenvironment would be another important influence factor to regulate the antitumor activity of BOC26P in vivo . In conclusion, these observations showed that the traditional phosphate prodrug strategy would be a promising and easy method to increase water solubility and anticancer activity of chalcones for the clinical developments of anticancer agents. [ABSTRACT FROM AUTHOR]

Natural mating colony cage systems for parent-stock layer breeders have been widely adopted by many commercial farms in China. However, the environment is still relatively barren, so enrichment devices such as claw abrasives can be provided. Hens living in wire cages lack the opportunity to abrade their claws, resulting in uncontrolled claw growth. The objective of this study was to investigate the effects of claw abrasive devices (CADs). Three different CADs were investigated: abrasive strips (T1), metal plates with holes (T2) and rubber mats with grooves (T3); cages without CADs acted as controls (T4). Claw length and sharpness, foot health, feather coverage, fear and physiological stress and mortality of the layer breeders were evaluated. Twelve replicates were used for each treatment, a total of 48 identical cages. Results showed that CADs had significant effects on claw length and sharpness of both hens and roosters. Birds in the T1 group had the shortest claw length and bluntest claw sharpness at 22, 32, 42, and 52 wk of age (P < 0.05). T1, T2, and T3 had higher scores for claw condition and significantly better overall plumage condition on the back and rump than T4 (P < 0.05). Hens in the T4 group were more susceptible to the tonic immobility, novel object, and avoidance distance tests. No significant differences were found between groups in concentration of triiodothyronine, thyroxine or 5-HT, except a significantly higher concentration of corticosterone in T4 compared to T1, T2, and T3 (P < 0.05). Overall mortality and mortality from cannibalism were both significantly higher in T4 than in T1, T2, and T3 (P < 0.05). In conclusion, hens with access to CADs during the laying period had shorter and blunter claws, less damaged plumage, a lower plasma corticosterone secretion and mortality rate and were less fearful. [ABSTRACT FROM AUTHOR]

The proteasomal 19S regulatory particle (RP) associated deubiquitinases (DUBs) have attracted much attention owing to their potential as a therapeutic target for cancer therapy. Identification of new entities against 19S RP associated DUBs and illustration of the underlying mechanisms is crucial for discovery of novel proteasome blockers. In this study, a series of 4-arylidene curcumin analogues were identified as potent proteasome inhibitor by preferentially blocking deubiquitinase function of proteasomal 19S RP with moderate 20S CP inhibition. The most active compound 33 exhibited a major inhibitory effect on 19S RP-associated ubiquitin-specific proteases 14, along with a minor effect on ubiquitin C-terminal hydrolase 5, which resulted in dysfunction of proteasome, and subsequently accumulated ubiquitinated proteins (such as IκB) in several cancer cells. Remarkably, though both 19S RP and 20S CP inhibition induced significantly endoplasmic reticulum stress and triggered caspase-12/9 pathway activation to promote cancer cell apoptosis, the 19S RP inhibition by 33 avoided slow onset time, Bcl-2 overexpression, and PERK-phosphorylation, which contribute to the deficiencies of clinical drug Bortezomib. These systematic studies provided insights in the development of novel proteasome inhibitors for cancer treatment. [ABSTRACT FROM AUTHOR]

• Birds treated with white and red light showed mating behaviour more frequently. • White and red light increased the proportion of complete matings and fertility. • All components of mating behaviour and fertility declined from 30 to 50 wks of age. • No significant correlation was found between fertility and mating behaviour. Natural mating colony cages for parent-stock layer breeders, instead of conventional cages with artificial insemination, have been widely adopted by many commercial farms in China. However, the fertility rate of this system varies greatly among different cage tiers. We speculated that the difference in fertility rate might be caused by uneven illumination because vision appears to play a central role in birds' behaviour, including mating. The objectives of this study were to investigate the effects of 4 LED light colours (white: WL, red: RL, yellow-orange: YO, and blue-green: BG), each at 2 light intensities (10 lx, 25 lx), on mating frequency and fertility for layer breeders in natural mating colony cages. A total of 32 identical cages were involved in the 8 treatments, with 4 replicates for each treatment and 5 males and 45 females per cage. The results showed significant effects of age, light colour, light intensity and colour-intensity interaction on the frequency of mating behaviour, integrity of matings and fertility. Overall, flocks treated with WL and RL and a higher light intensity during the laying period showed more frequent mating behaviour, a larger proportion of relatively complete matings and a higher fertility. All components of mating behaviour and fertility declined from 30 wks to 50 wks of age, but no significant correlation was found between fertility and mating behaviour. In summary, the results of this study illustrate that differences in LED light colour and light intensity influenced the mating behaviour and fertility of layer breeders. WL and RL and a higher light intensity can increase the frequency of mating behaviour, the proportion of complete matings and fertility. No significant correlation was found between fertility and mating behaviour. Such knowledge can help to understand mating behaviour in natural mating colony cages and provide a basis for optimization of the light environment. [ABSTRACT FROM AUTHOR]

• Colony cages for layer breeders have been widely adopted by many farms in China. • Feather pecking and cloacal cannibalism are serious in the colony cage system. • Providing nests, claw abrasive devices may be an effective welfare-oriented method. • Large nests, abrasive strips can effectively reduce feather pecking and stress level. Natural mating colony cages for parent-stock layer breeders, instead of conventional cages with artificial insemination, have been widely adopted by many commercial farms in China. Although some natural mating behaviours can be expressed and broader activity space is provided compared with that of conventional artificial insemination cages, the environment is still relatively barren. The aim of this study was to investigate the effects of providing nest boxes and claw abrasive devices (CADs) in this colony cage system on feather pecking (FP), feather condition, fear and physiological stress in layer breeders. Twelve treatments were compared in a factorial arrangement, including 2 types of nests (large and small), 3 types of CADs (abrasive strips, rubber mat with grooves, and metal plates with holes), and the control (without the provision of nests and CADs). Nine cages per treatment were involved, with 10 roosters and 90 hens per cage. The results showed that the nests had a significant effect (P ≤ 0.05) on the frequency of severe feather pecking (SFP); environmental pecking (ENP); food pecking (FOP); back, rump, and belly coverage condition; tonic immobility (TI) duration; avoidance distance (AD); and corticosterone and 5-HT concentrations. Except for the blood parameters, the CADs had a significant effect (P ≤ 0.05) on the frequency of SFP and FOP; back, rump, tail coverage condition; duration and latency of TI test; hens' novel object (NO) recognition score; and distance in the AD test. In addition, significant nest × CAD interactions (P ≤ 0.05) were noted for SFP, ENP, and FOP; back, rump, and tail coverage condition; duration in the TI test; hens' novel object (NO) recognition score; distance in the AD test; and the concentration of corticosterone. Mortality was significantly (P ≤ 0.05) reduced by nests, CADs and their interaction. It was concluded that the nests and CADs that were equipped in our study could be regarded as rewarding environmental necessities that could alleviate FP activities, improve feather coverage condition, and reduce stress levels and mortality rates. Large nests and abrasive strips were the preferred choice over colony cages without nests and CADs. [ABSTRACT FROM AUTHOR]