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Rye (Secale cereale) is a valuable gene donor for wheat improvement, especially for its resistance to diseases. Developing rye-derived resistance sources is important for wheat breeding. In the present study, two wheat-rye derivatives, designated JS016 and JS110, were produced by crossing common wheat cultivar Yangmai 23 with Pakistani rye accession W2A. Using sequential genomic in situ hybridization (GISH) and multicolor fluorescence in situ hybridization (mc-FISH), JS016 and JS110 were identified as a T6BS.6RL translocation line and a T6BS.6BL6RL translocation line, respectively. Ten newly 6RL chromosome arm-specific markers were developed and used to confirm the 6RL translocation. The wheat 55K single-nucleotide polymorphism (SNP) array further verified the molecular cytogenetic identification results above and clarified their breakpoints at 430.9 and 523.0 Mb of chromosome 6B in JS016 and JS110, respectively. Resistance spectrum and allelism test demonstrated that JS016 and JS110 possessed novel powdery mildew resistance gene(s) that was derived from the 6RL translocation but differed from Pm20. Moreover, JS016 and JS110 had better agronomic traits than the previously reported 6RL translocation line carrying Pm20. To efficiently transfer and detect the 6RL translocation from JS016 and JS110, one 6RL-specific Kompetitive allele specific PCR (KASP) marker was developed and validated in high throughput marker-assisted selection (MAS).

Abstract Powdery mildew, caused by Blumeria graminis f. sp. tritici (Bgt), is a serious fungal disease that critically threatens the yield and quality of wheat. Utilization of host resistance is the most effective and economical method to control this disease. In our study, a wheat breeding line ShiCG15–009, released from Hebei Province, was highly resistant to powdery mildew at all stages. To dissect its genetic basis, ShiCG15–009 was crossed with the susceptible cultivar Yannong 21 to produce F1, F2 and F2:3 progenies. After genetic analysis, a single dominant gene, tentatively designated PmCG15–009, was proved to confer resistance to Bgt isolate E09. Further molecular markers analysis showed that PmCG15–009 was located on chromosome 2BL and flanked by markers XCINAU130 and XCINAU143 with the genetic distances 0.2 and 0.4 cM, respectively, corresponding to a physic interval of 705.14–723.48 Mb referred to the Chinese Spring reference genome sequence v2.1. PmCG15–009 was most likely a new gene differed from the documented Pm genes on chromosome 2BL since its different origin, genetic diversity, and physical position. To analyze and identify the candidate genes, six genes associated with disease resistance in the candidate interval were confirmed to be associated with PmCG15–009 via qRT-PCR analysis using the parents ShiCG15–009 and Yannong 21 and time-course analysis post-inoculation with Bgt isolate E09. To accelerate the transfer of PmCG15–009 using marker-assisted selection (MAS), 18 closely or co-segregated markers were evaluated and confirmed to be suitable for tracing PmCG15–009, when it was transferred into different wheat cultivars.

Powdery mildew of wheat (Triticum aestivum), caused by Blumeria graminis f.sp. tritici (Bgt), is a destructive disease that seriously threatens the yield and quality of its host. Identifying resistance genes is the most attractive and effective strategy for developing disease-resistant cultivars and controlling this disease. In this study, a wheat breeding line Yannong 99102-06188 (YN99102), an elite derivative line from the same breeding process as the famous wheat cultivar Yannong 999, showed high resistance to powdery mildew at the whole growth stages. Genetic analysis was carried out using Bgt isolate E09 and a population of YN99102 crossed with a susceptible parent Jinhe 13–205 (JH13–205). The result indicated that a single recessive gene, tentatively designated pmYN99102, conferred seedling resistance to the Bgt isolate E09. Using bulked segregant exome capture sequencing (BSE-Seq), pmYN99102 was physically located to a ~33.7 Mb (691.0–724.7 Mb) interval on the chromosome arm 2BL, and this interval was further locked in a 1.5 cM genetic interval using molecular markers, which was aligned to a 9.0 Mb physical interval (699.2–708.2 Mb). Based on the analysis of physical location, origin, resistant spectrum, and inherited pattern, pmYN99102 differed from those of the reported powdery mildew (Pm) resistance genes on 2BL, suggesting pmYN99102 is most likely a new Pm gene/allele in the targeted interval. To transfer pmYN99102 to different genetic backgrounds using marker-assisted selection (MAS), 18 closely linked markers were tested for their availability in different genetic backgrounds for MAS, and all markers expect for YTU103-97 can be used in MAS for tracking pmYN99102 when it transferred into those susceptible cultivars.

Powdery mildew of wheat, caused by Blumeria graminis f. sp. tritici (Bgt), is a devastating disease that seriously reduces yield and quality worldwide. Utilization of plant resistance genes is an attractive and effective strategy for controlling this disease. Among the reported powdery mildew (Pm) resistance genes, Pm2 exhibits a diverse resistance spectrum among its multiple alleles. It has been widely used in China for resistance breeding for powdery mildew. To mine more Pm2 alleles and clarify their distribution, we screened 33 wheat cultivars/breeding lines carrying Pm2 alleles from 641 wheat genotypes using diagnostic and Pm2-linked markers. To further investigate the relationships within the Pm2 alleles, we compared their resistance spectra, polymorphism of marker alleles and gene sequences, and found that they have identical marker alleles and gene sequences but diverse resistance spectra. In addition, the diagnostic kompetitive allele-specific PCR (KASP) marker, YTU-KASP-Pm2, was developed and was shown to detect all the Pm2 alleles in the different genetic backgrounds. These findings provide valuable information for the distribution and rational use of Pm2 alleles, push forward their marker-assisted breeding (MAS), and hence improve the control of wheat powdery mildew.

Abstract Background The tongue-rolling behaviour of cows is regarded as an outward sign of stressed animals in a low welfare status. The primary aim of this observational study was to evaluate the association between the frequency of tongue-rolling behaviour and its physiological function. The secondary aim was to explore the relationship between general activities and the frequency of tongue-rolling behaviour of cows. A total of 126 scan sampling behavioural observations were collected over 7 d on 348 Holstein cows with the same lactation stage in the same barn. The tongue-rolling frequency was defined as the number of tongue-rolling observations as a percentage to the total observations per individual cow. According to their tongue-rolling frequency, the cows were grouped into the CON (no tongue-rolling), LT (frequency 1%), MT (frequency 5%), and HT (frequency 10%) groups. Six cows from each group were randomly selected for sampling. Serum samples, rumen fluid, milk yield, and background information were collected. The general behaviour data during 72 continuous hours of dairy cows, including eating time, rumination time, food time (eating time + rumination time), and lying time, were recorded by the collar sensor. Results Cortisol (P = 0.012), γ-hydroxybutyric acid (P = 0.008), epinephrine (P = 0.030), and dopamine (P = 0.047) levels were significantly higher in tongue-rolling groups than in the CON group. Cortisol levels and tongue-rolling frequency had a moderate positive correlation (linearly r = 0.363). With the increase in tongue-rolling frequency, the rumen pH decreased first and then increased (P = 0.013), comparing to the CON group. HT cows had significantly less food time than CON cows (P = 0.035). The frequency of tongue-rolling had a moderate negative relationship with rumination time (r = −0.384) and food time (r = −0.492). Conclusions The tongue-rolling behaviour is considered as a passive coping mechanism, as the stress response in cows with high tongue-rolling frequency increased. Food intake and rumination activities were all closely related to the occurrence of tongue-rolling behaviour.

Abstract Background Abnormal or stereotyped behaviours in dairy cows are common in large-scale indoor farms and are usually accompanied by high physiological stress levels. Feed tossing is an abnormal behaviour commonly seen in cows while being fed, making farm management difficult. However, the reasons behind this behaviour have not been sufficiently reported. The objective of this study was to explore the changes in rumen fermentation, serum indicators, inflammatory conditions and the performance of cows with feed tossing behaviour. Holstein cows with similar lactation stages in the same barn were subjected to behaviour observations two times per day for 21 consecutive days. Ten cows with feed tossing behaviour (FT) and ten cows without abnormal behaviours (CON) were selected for further sampling. Plasma samples, rumen fluid, milk yield data of cows, and an indoor environment temperature-humidity index (THI) were collected. Results There was no significant difference in average daily milk yield during the observation period between feed-tossing cows (n = 68) and the other cows (n = 112). The number of cows showing FT behaviour had a moderately strong negative linear correlation with the THI of the environment. Compared to the CON cows, the FT cows had higher cortisol, norepinephrine and urea nitrogen levels in plasma, as well as higher plasma levels of inflammatory indicators, including total protein, lactate dehydrogenase, albumin, aspartate aminotransferase levels, and the ratio of aspartate aminotransferase to alanine aminotransferase. The FT cows had no significant variations from the CON cows regarding their rumen fermentation indicators, such as pH, ammonia nitrogen, and volatile fatty acids. In addition, 16S rRNA analysis revealed that there might be no clear association between the diversity and abundance of rumen bacteria and feed tossing behaviour. Conclusions Our findings suggested that cows might have suffered from high levels of physiological stress and immune state for a long period when they exhibited FT behaviour. The environmental THI could affect the FT behaviour of cows; as the THI increases, the willingness of cows to throw decreases. This work provided the first evidence that feed tossing might be a response associated with high levels of physiological stress and immune. It also explored our insights into a commonly observed behavioural response to cow welfare traits.

Heat stress affects production and health in cows severely. Since it is difficult to define heat-tolerant animals, studies of response to heat stress are important for understanding dairy cows’ health and production. However, information on the impact of heat stress on various indicators in heat-tolerant and heat-sensitive cows is sparse. This study aimed to investigate the effects of heat stress (HS) on blood, production, and physiological indicators in heat-tolerant and heat-sensitive cows. A total of 43 dairy cows were used from 9 May to 7 August 2021, under Temperature–Humidity Index (THI) measurements that ranged from 65.9 to 86.7. We identified cows that were tolerant or sensitive to HS based on the slope of the response of physiological and production traits against THI during the HS period by using a clustering method. After HS, serum glucose (Glu), cortisol (COR), 5-hydroxytryptamine (5-HT), and interleukin-6 (IL-6) levels of cows in the heat-tolerant group were lower than in the heat-sensitive group (p < 0.05). With THI as the predictor, the R2 for predicting respiration rate (RR) and body surface temperature (BT) in heat-tolerant cows was 0.15 and 0.16, respectively, whereas the R2 for predicting RR and BT in heat-sensitive cows was 0.19 and 0.18, respectively. There were low to moderate, positive correlations between RR, BT, and MY with THI, with Pearson correlation coefficients ranging from r = 0.11 to 0.4 in the heat-tolerant group, and from r = 0.24 to 0.43 in the heat-sensitive group. There was a low positive correlation between VT and THI, with a Spearman correlation coefficient of r = 0.07 in the heat-sensitive group. The heat-tolerant dairy cows had lower MY losses and had lower MY (p = 0.0007) in mixed models. Heat-tolerant cows with low-stress levels, through upregulating RR rapidly, increased their adaptability to thermal environments. They have better thermoregulation capability; the hypothalamic–pituitary–adrenal (HPA) axis regulated the thermoregulatory in animals by releasing a variety of neurotransmitters and hormones.

The frequency synthesizer plays a crucial role in atomic clock technology. In this study, we demonstrate a direct microwave frequency synthesizer for a cesium atomic clock, employing frequency multiplication and a dual-phase-locked loop mode. A mathematical model of the frequency synthesis chain is established to estimate its performance. The phase-settling time and system stability are analyzed and studied in detail, and the obtained results are verified by experiments. An optimized realization of the frequency synthesizer shows that the phase-settling time can be adjusted within the range of 644.5 µs to 1.5 ms. Additionally, we measure the absolute phase noise values to be −63.7 dBc/Hz, −75.7 dBc/Hz, −107.1 dBc/Hz, and −122.5 dBc/Hz at 1 Hz, 10 Hz, 1 kHz, and 10 kHz offset frequencies, respectively.

Eye temperature (ET) has long been used for predicting or indicating heat stress in dairy cows. However, the region of interest (ROI) and temperature parameter of the eye have not been standardized and various options were adopted by previous studies. The aim of this study was to determine the best ROI for measuring ET as the predictor of heat stress in dairy cows in consideration of repeatability and validity. The ET of 40 lactating Holstein dairy cows was measured using infrared thermography. The mean and maximum temperature of five ROIs—medial canthus (MC), lateral canthus, eyeball, whole eye (WE), and lacrimal sac (LS)—were manually captured. The results show that the ET of left eyes was slightly higher than that of right eyes. The ET taken in MC, WE, and LS within 2 min had a moderate to substantial repeatability. The maximum temperature obtained at the LS had the highest correlation coefficients with respiration rate and core body temperature (all p < 0.001). Therefore, the maximum temperature of LS should be considered by future studies that want to use ET as the predictor or indicator of heat stress in dairy cows.

Non-nutritive oral behaviors, especially tongue rolling, are prevalent in the stabled cow population. These behaviors mean that the environment or management process might not suit the cows, suggesting low welfare. However, few researches have reported the physiological indicators or production performance of dairy cows with the stereotyped behavior. This study aimed to determine physical conditions, daily activity, rumen fermentation, and milk production of cows with tongue-rolling behavior. Three hundred and fifty nine Holstein cows in the same barn and lactation stage were subjected to scan sampling behavior observations 126 times for 7 days. Ten cows with high-frequency tongue-rolling behavior (TON) and 10 cows without abnormal oral behavior (CON) were selected for further study. Serum sample, ruminal fluid, milk sample, and behavior record video of TON and CON cows were collected. TON cows had more drinking behavior and more stable lying behavior than the CON cows during the daytime. The body condition score of the TON cows decreased, while the milk yield, yield of milk fat, protein, and lactose in the study period increased. The TON cows had lower ruminal fluid pH, acetate/propionate ratio, and total volatile acid. The bacterial diversity in the ruminal fluid was not different between the two groups. Compared to CON cows, the TON cows had a higher level of serum stress indicators, such as cortisol, thyroid hormone, and norepinephrine, which positively correlated to the frequency of tongue-rolling behavior. Meanwhile, the TON cows had a higher level of lactate dehydrogenase, serum glucose, total triglyceride, total cholesterol, and Interleukin 6. Overall, it means they suffer from higher levels of stress and have higher energy metabolism for a long time when cows show tongue-rolling behavior. TON cows had suffered a higher stress level and had higher energy metabolic status for a long time. The TON cows might have better heat tolerance to the thermal environment by more lying and drinking time. Our data revealed the changes in milk production, physiological stress indicators of dairy cows with high-frequency tongue rolling behavior, which will provide essential knowledge for the in-depth understanding of tongue rolling behavior in dairy cows.

Objective An experiment was conducted to evaluate the effects of Lonicera japonica extract (LJE) on milk production, rumen fermentation and blood biomarkers of energy metabolism, inflammation and oxidative stress during the perinatal period of Holstein dairy cows. Methods Eighteen Holstein dairy cows were used in a complete randomized design experiment with 3 dietary treatments and 6 cows per treatment. All cows received the same basal total mixed ration (TMR) including a prepartal diet (1.35 Mcal of net energy for lactation [NEL]/kg of dry matter [DM], 13.23% crude protein [CP]) from −60 d to calving and a postpartal diet (1.61 Mcal of NEL/kg of DM, 17.39% CP) from calving to 30 days in milk (DIM). The 3 dietary treatments were TMR supplemented with LJE at 0 (control), 1 and 2 g/kg DM, respectively. LJE was offered from 21 d before calving to 30 DIM. Dry matter intake (DMI) and milk production were measured daily after calving. Milk and rumen fluid samples were collected on 29 and 30 d after calving. On −10, 4, 14, and 30 d relative to calving, blood samples were collected to analyze the biomarkers of energy metabolism, inflammation and oxidative stress. Results Compared with control diet, LJE supplementation at 1 and 2 g/kg DM increased DMI, milk yield and reduced milk somatic cell count. LJE supplementation also decreased the concentrations of blood biomarkers of pro-inflammation (interleukin-1β [IL-1β], IL-6, and haptoglobin), energy metabolism (nonesterified fatty acid and β-hydroxybutyric acid) and oxidative stress (reactive oxygen metabolites), meanwhile increased the total antioxidant capacity and superoxide dismutase concentrations in blood. No differences were observed in rumen pH, volatile fatty acid, and ammonia-N (NH3-N) concentrations between LJE supplemented diets and the control diet. Conclusion Supplementation with 1 and 2 g LJE/kg DM could increase DMI, improve lactation performance, and enhance anti-inflammatory and antioxidant capacities of dairy cows during perinatal period.

Abstract Ruminal thiamine deficiencies occur when dairy cows are overfed with high-concentrate diet, and thiamine supplementation has been proved to attenuate high-concentrate diet induced SARA. However, there is limited knowledge of the relationship between thiamine supplementation in high-concentrate diets and ruminal fungi. In order to investigate the impacts of thiamine supplementation on ruminal fungi, twelve Chinese Holstein dairy cows were randomly assigned into three treatments: control diet (CON; 20% starch, dry matter basis), high-concentrate diet (HC; 33.2% starch, dry matter basis) and high-concentrate diet supplemented with 180 mg thiamine/kg dry matter intake. Dry matter intake and milk production were recorded during the experimental periods. On day 21, rumen fluid samples were collected at 3 h postfeeding and ruminal pH, thiamine concentration and volatile fatty acids were measured. Metagenome sequencing method was conducted to detect ruminal fungi composition. Feeding HC significantly decreased dry matter intake, milk production, ruminal pH, ruminal acetate and thiamine concentration, however, significantly increased propionate and isovalerate (P

Background: Thiamine supplementation in high-concentrate diets (HC) was confirmed to attenuate ruminal subacute acidosis through promoting carbohydrate metabolism, however, whether thiamine supplementation in HC impacts methane metabolism is still unclear. Therefore, in the present study, thiamine was supplemented in the high-concentrate diets to investigate its effects on ruminal methanogens and methanogenesis process. Methods: an in vitro fermentation experiment which included three treatments: control diet (CON, concentrate/forage = 4:6; DM basis), high-concentrate diet (HC, concentrate/forage = 6:4; DM basis) and high-concentrate diet supplemented with thiamine (HCT, concentrate/forage = 6:4, DM basis; thiamine supplementation content = 180 mg/kg DM) was conducted. Each treatment concluded with four repeats, with three bottles in each repeat. The in vitro fermentation was sustained for 48h each time and repeated three times. At the end of fermentation, fermentable parameters, ruminal bacteria and methanogens community were measured. Results: HC significantly decreased ruminal pH, thiamine and acetate content, while significantly increasing propionate content compared with CON (p < 0.05). Conversely, thiamine supplementation significantly increased ruminal pH, acetate while significantly decreasing propionate content compared with HC treatment (p < 0.05). No significant difference of ruminal methanogens abundances among three treatments was observed. Thiamine supplementation significantly decreased methane production compared with CON, while no significant change was found in HCT compared with HC. Conclusion: thiamine supplementation in the high-concentrate diet (HC) could efficiently reduce CH4 emissions compared with high-forage diets while without causing ruminal metabolic disorders compared with HC treatment. This study demonstrated that supplementation of proper thiamine in concentrate diets could be an effective nutritional strategy to decrease CH4 production in dairy cows.

As the co-enzyme of pyruvate formate-lyase under ruminal anaerobic condition, thiamine plays a critical role in carbohydrate metabolism in dairy cows. The objective of this study was to investigate the impacts of thiamine supplementation on ruminal carbohydrate-active enzymes. Twelve Holstein dairy cows were randomly assigned into three dietary treatments: control diet (CON; 20% starch, dry matter (DM) basis), high-concentrate diet (HC; 33.2% starch, DM basis) and a high-concentrate diet supplemented with 180 mg thiamine/kg DM (HCT; 33.2% starch, DM basis). Dry matter intake and milk production were recorded for 21 days. Rumen fluid samples were collected, and ruminal pH and volatile fatty acids (VFAs) were measured. The metagenome sequencing technique was used to detect the genes in ruminal microorganisms and identify putative carbohydrate-active enzymes. The total abundances of carbohydrate-active enzymes and fiber-degrading enzymes were both reduced by HC with no effect on starch-degrading enzymes compared with CON. However, the fiber-degrading enzymes and starch-degrading enzymes were both increased after thiamine supplementation. These results indicated that 180 mg thiamine /kg DM might effectively improve rumen carbohydrate metabolism through increasing the abundance of ruminal carbohydrate-active enzymes and consequently balanced the rumen volatile fatty acids and rumen pH, providing a practical strategy in preventing subacute ruminal acidosis in cows offered HC.

A series of 1,4-bis(2-substituted-1,3,4-oxadiazole)benzene derivatives has been designed to explore their optical, electronic, and charge transport properties for luminescent and charge transport materials. The frontier molecular orbitals (FMOs) analysis have turned out that the vertical electronic transitions of absorption and emission are characterized as intramolecular charge transfer (ICT). Both λabs and λfl of the derivatives with 2-thiophene and 2-1H-pyrrole fragments show bathochromic shifts compared with parent compound 2-pyridyl substituted derivative (1), while the corresponding values of the substituted derivatives with 4-pyridyl, 2-pyrazine, and phenyl fragments are similar to those of parent compound 1. Our results suggest that the substituted derivatives with 4-pyridyl, 2-pyrazine, phenyl, 2-thiophene, and 2-1H-pyrrole fragments are expected to be promising candidates for luminescent materials for OLEDs. Furthermore, the substituted derivatives with 4-pyridyl, 2-pyrazine, phenyl, and 2-thiophene fragments can be used as promising electron transport materials, while the substituted derivatives with 2-pyrazine and 2-1H-pyrrole fragments can be used as promising hole transport materials. In addition, the substituted derivative with 2-pyrazine fragment may be used as good candidate for ambipolar charge transport material for OLEDs.

Background: Kelp powder, which was rich in novel oligosaccharides and iodine might be utilized by the rumen microbiome, promoted the ruminal fermentation and finally enhanced the lactation performance of dairy cows. Therefore, the purpose of this study was to investigate the effects of kelp powder partially replacing dietary forage on rumen fermentation and lactation performance of dairy cows. (2) Methods: In the present study, 20 Chinese Holstein dairy cows were randomly divided into two treatments, a control diet (CON) and a kelp powder replacing diet (Kelp) for a 35-d long trial. Dry matter intake (DMI), milk production, milk quality, ruminal fermentable parameters, and rumen microbiota were measured to investigate the effects of kelp powder feeding on dairy cows. (3) Results: On the lactation performance, kelp significantly increased milk iodine content and effectively enhanced milk production and milk fat content. On the fermentable aspects, kelp significantly raised TVFA while reducing the ammonia-N content. On the rumen microbial aspect, kelp feeding significantly promoted the proliferation of Firmicutes and Proteobacteria while suppressing Bacteroidetes. (4) Conclusion: kelp powder as an ingredient of feedstuff might promote the rumen fermentation ability and effectively increase milk fat and iodine content, and consequently improve the milk nutritional value.

Rice stripe, a virus disease, transmitted by a small brown planthopper (SBPH), has greatly reduced production of japonica rice in East Asia, especially in China. Although we have made great progress in mapping resistance genes, little is known about the mechanism of resistance. By de novo transcriptome assembling, we gained sufficient transcript data to analyze changes in gene expression of early interaction in response to SBPH and RSV infection in rice. Respectively 648 and 937 DEGs were detected from the disease-resistant (Liaonong 979) and the susceptible (Fengjin) varieties, most of which were up-regulated. We found 37 genes related to insect resistance, which mainly included genes for jasmonate-induced protein, TIFY protein, lipoxygenase, as well as trypsin inhibitor genes and transcription factor genes. In the interaction process between RSV and rice, 87 genes were thought to be related to RSV resistance; these primarily included 12 peroxidase biosynthesis genes, 12 LRR receptor-like protein kinase genes, 6 genes coding pathogenesis-related proteins, 4 glycine-rich cell wall structural protein genes, 2 xyloglucan hydrolase genes and a cellulose synthase. The results indicate that the rice-pathogen interaction happened both in disease-resistant and susceptible varieties, and some genes related to JA biosynthesis played key roles in the interaction between SBPHs and rice. When rice was infected by RSV a hypersensitive reaction (HR) in the disease-resistant variety was suppressed, which resulted from an increase in peroxidase expression and down-regulation of LRR receptor-like protein kinase and pathogenesis-related proteins, while, the changes of peroxidase biosynthesis, glycine-rich cell wall structural protein, cellulose synthase and xyloglucan endotransglucosylase/hydrolase could lead to the strengthening of physical barriers of rice, which may be an important resistance mechanism to RSV in rice.