Effect of the Severity of Short-Term Feed Restriction on Gut Function

The objective of this study was to evaluate whether different severities of short-term feed restriction (FR) affect the absorptive function of the reticulo-rumen and total tract barrier function in beef cattle and also to determine the timeline for recovery of these functions. Eighteen ruminally cannulated and ovariectomized Angus × Hereford heifers were blocked by BW and randomly assigned to 1 of 3 treatments differing in the severity of FR. Feed offered was restricted to 75, 50 and 25% of the ad libitum feed intake measured during FR relative to that measured during the 5-d baseline period (BASE). Feed restriction (FR) was imposed for 5 d followed by 3 consecutive wk of recovery in which cattle were fed ad libitum (REC1, REC2 and REC3). Throughout the study, heifers were housed in individual pens (9 m2) and were fed the same diet (60% forage: 40% concentrate) with free access to water. Dry matter intake (DMI) was measured daily and ruminal pH was measured every 2 min throughout the study. Ruminal fluid and blood samples were collected on d 3 of the BASE and FR and on d 5 of REC1 and REC3. The temporarily isolated and washed reticulo-rumen technique (WRR) was used to evaluate short-chain fatty acid (SCFA) absorption on the last day of BASE, FR, REC1 and REC3. Total tract barrier function was evaluated starting on d 2 of the BASE and FR and on d 4 of REC1 and REC3 using a pulse dose of chromium ethylenediaminetetraacetic acid (Cr-EDTA) followed by 48-h of total urine collection. Dry matter intake did not differ among treatments during BASE but, as imposed by the experimental model, DMI during FR relative to BASE equated to 70, 49, and 25%, which was close to the targeted values of 75, 50, and 25% (treatment × period, P < 0.001). A treatment × period interaction (P < 0.001) was also detected for SCFA concentration with the concentration decreasing as the severity of FR increased, whereas there were no differences during BASE. Absorption of SCFA across the reticulo-rumen tended to decrease with increasing severity of FR (P = 0.080). Acetate absorption (mmol/h) decreased (P = 0.050) by almost 70 mmol/h at 25 and 50% feed relative to BASE (322 mmol/h). Heifers restricted to 25% feed had greater urinary Cr recovery during FR than BASE while no changes were detected for those restricted to 75 and 50%. After FR, DMI (% BW) increased rapidly in REC1 for heifers restricted to 75 and 50%; however heifers restricted to 25% needed at least 2 wk to recover (treatment × period, P < 0.001). Regardless of the severity of FR, the duration that pH < 5.5 was highest during REC1 (period P < 0.001). A treatment × period interaction was observed for the absolute absorption rate of total SCFA (P = 0.009) where the total SCFA absorption rate was not different for heifers restricted to 75 and 50% across periods while an increase from FR and REC1 to REC3 was detected for heifers restricted to 25% of ad libitum intake. A treatment effect was observed for urinary Cr output (P = 0.027) indicating that heifers previously restricted to 25% of ad libitum intake had greater Cr excretion in urine during recovery. This study indicates that moderate short-term FR has negative effects on the absorptive function of the reticulo-rumen but more severe FR is required to compromise total tract barrier function in beef cattle. Severe FR also negatively affects the time required for recovery of reticulo-rumen absorptive function and total tract barrier function. Regardless of severity, FR increases risk for ruminal acidosis when heifers have free access to feed after FR

Brooding fathers actively consume viable embryos to take up nutrients in a monogamous syngnathid fish

Syngnathid fishes often experience a reduction in brood size and an increase in immunity during pregnancy. Researchers have studied the polygamous broad-nosed pipefish (Syngnathus typhle) and revealed that some eggs from low-quality females in the male’s brood pouch serve as nurse eggs that are absorbed by the father. It is unclear whether nurse eggs also exist in other syngnathid fishes, especially in monogamous syngnathid fishes. In monogamous syngnathid fishes, the male pouch only carries eggs from a single female. Thus, the question remains: do some eggs of monogamous syngnathid fishes also serve as nurse eggs? And if so, are these nurse eggs impaired eggs, or are they viable eggs that are consumed by the brooding father? In the present study, we used the monogamous lined seahorse (Hippocampus erectus) and asked whether nurse eggs exist in this species. We also explored whether nurse eggs potentially originate from viable versus inviable eggs. Using isotope labeling, we found that nutrients from embryos could be transferred to brooding fathers. Furthermore, we also found that brooding fathers with limited food had a higher isotope content and a smaller brood size compared to individuals with sufficient food. These results have demonstrated that nurse eggs exist in the lined seahorse, and also suggested that the brooding fathers actively consume viable embryos to absorb nutrients in response to low food availability. These findings help us better understand parent–embryo conflict, filial cannibalism, and male-only care in teleost fishes

Biodegradation of Dimethyl Phthalate by Freshwater Unicellular Cyanobacteria

The biodegradation characteristics of dimethyl phthalate (DMP) by three freshwater unicellular organisms were investigated in this study. The findings revealed that all the organisms were capable of metabolizing DMP; among them, Cyanothece sp. PCC7822 achieved the highest degradation efficiency. Lower concentration of DMP supported the growth of the Cyanobacteria; however, with the increase of DMP concentration growth of Cyanobacteria was inhibited remarkably. Phthalic acid (PA) was detected to be an intermediate degradation product of DMP and accumulated in the culture solution. The optimal initial pH value for the degradation was detected to be 9.0, which mitigated the decrease of pH resulting from the production of PA. The optimum temperature for DMP degradation of the three species of organisms is 30 ∘ C. After 72 hours&apos; incubation, no more than 11.8% of the residual of DMP aggregated in Cyanobacteria cells while majority of DMP remained in the medium. Moreover, esterase was induced by DMP and the activity kept increasing during the degradation process. This suggested that esterase could assist in the degradation of DMP

On-site and visual detection of sorghum mosaic virus and rice stripe mosaic virus based on reverse transcription-recombinase-aided amplification and CRISPR/Cas12a

Rapid, sensitive and visual detection of plant viruses is conducive to effective prevention and control of plant viral diseases. Therefore, combined with reverse transcription and recombinase-aided amplification, we developed a CRISPR/Cas12a-based visual nucleic acid detection system targeting sorghum mosaic virus and rice stripe mosaic virus, which cause harm to crop production in field. When the RT-RAA products were recognized by crRNA and formed a complex with LbCas12a, the ssDNA labeled with a quenched green fluorescent molecule will be cleaved by LbCas12a, and then a significant green fluorescence signal will appear. The entire detection process can be completed within 30 min without using any sophisticated equipment and instruments. The detection system could detect samples at a dilution of 107, about 104-fold improvement over RT-PCR, so the system was successfully to detect rice stripe mosaic virus in a single leafhopper, which is the transmission vector of the virus. Finally, the CRISPR/Cas12a-based detection system was utilized to on-site detect the two viruses in the field, and the results were fully consistent with that we obtained by RT-PCR in laboratory, demonstrating that it has the application prospect of detecting important crop viruses in the field

Numerical and experimental evaluation of nasopharyngeal aerosol administration methods in children with adenoid hypertrophy

Article no 12390

Perceção de mulheres grávidas relativamente à informação disponível acerca do consumo de álcool durante a gravidez

info:eu-repo/semantics/draf

Synthesis and Photoluminescence Properties of Porous Silicon Nanowire Arrays

Herein, we prepare vertical and single crystalline porous silicon nanowires (SiNWs) via a two-step metal-assisted electroless etching method. The porosity of the nanowires is restricted by etchant concentration, etching time and doping lever of the silicon wafer. The diffusion of silver ions could lead to the nucleation of silver nanoparticles on the nanowires and open new etching ways. Like porous silicon (PS), these porous nanowires also show excellent photoluminescence (PL) properties. The PL intensity increases with porosity, with an enhancement of about 100 times observed in our condition experiments. A “red-shift” of the PL peak is also found. Further studies prove that the PL spectrum should be decomposed into two elementary PL bands. The peak at 850 nm is the emission of the localized excitation in the nanoporous structure, while the 750-nm peak should be attributed to the surface-oxidized nanostructure. It could be confirmed from the Fourier transform infrared spectroscopy analyses. These porous SiNW arrays may be useful as the nanoscale optoelectronic devices