Patterns of alteration in boar semen quality from 9 to 37 months old and improvement by protocatechuic acid

Background Comprehending the patterns of alteration in boar semen quality and identifying effective nutritional interventions are crucial for enhancing the productivity of commercial pig systems.This study aimed to examine the alteration in semen quality in boars,and assess the impact of protocatechuic acid(PCA)on semen quality during the phase of declining semen quality.Methods In Exp.1,a total of 38 Pig Improvement Company(PIC)boars were selected and their semen quality data were recorded from the age of 9 to 37 months.In Exp.2,18 PIC boars(28 months old)were randomly assigned into three groups(n=6)and fed a basal diet,a basal diet containing 500 or 1,000 mg/kg PCA,respectively.The experiment lasted for 12 weeks.Results The semen volume,concentration,and total number of spermatozoa in boars exhibited an increase from 9 to 19 months old and showed a significant linear decreased trend in 28,24,and 22 months old.Sperm motility displayed an upward trajectory,reaching its peak at 20 months of age,and showed a significant linear decreased trend at 20 months old.Dietary supplementation of PCA demonstrated an effect to mitigate the decrease in semen volume,concentration of spermatozoa,total number of spermatozoa(P>0.05),and significantly increased the sperm motility(P<0.05).Moreover,supplementation of 1,000 mg/kg PCA significantly increased the sperm viability(P<0.05).Analysis on cellular signaling pathways revealed that PCA restored serum testosterone levels and alleviated oxidative damage by upregulating the expression of HO-1,SOD2,and NQO1 in testicular stromal cells.Notably,PCA can enhance phosphorylation by selectively binding to AMP-activated protein kinase(AMPK)protein,thereby improving sperm mitochondrial function and augmenting sperm motility via PGC-1/Nrf1.Conclusions These data elucidated the pattern of semen quality variation in boars within the age range of 9 to 37 months old,and PCA has the potential to be a natural antioxidant to enhance sperm quality through modulation of the AMPK/PGC-1/Nrf1 signaling pathway.

Pectin modulates intestinal immunity in a pig model via regulating the gut microbiota-derived tryptophan metabolite-AhR-IL22 pathway

Background Pectin is a heteropolysaccharide that acts as an intestinal immunomodulator,promoting intestinal development and regulating intestinal flora in the gut.However,the relevant mechanisms remain obscure.In this study,pigs were fed a corn-soybean meal-based diet supplemented with either 5%microcrystalline cellulose(MCC)or 5%pectin for 3 weeks,to investigate the metabolites and anti-inflammatory properties of the jejunum.Result The results showed that dietary pectin supplementation improved intestinal integrity(Claudin-1,Occludin)and inflammatory response[interleukin(IL)-10],and the expression of proinflammatory cytokines(IL-1β,IL-6,IL-8,TNF-α)was down-regulated in the jejunum.Moreover,pectin supplementation altered the jejunal microbiome and tryptophan-related metabolites in piglets.Pectin specifically increased the abundance of Lactococcus,Enterococcus,and the microbiota-derived metabolites(skatole(ST),3-indoleacetic acid(IAA),3-indolepropionic acid(IPA),5-hydroxyindole-3-acetic acid(HIAA),and tryptamine(Tpm)),which activated the aryl hydrocarbon receptor(AhR)pathway.AhR activation modulates IL-22 and its downstream pathways.Correlation analysis revealed the potential relationship between metabolites and intestinal morphology,intestinal gene expression,and cytokine levels.Conclusion In conclusion,these results indicated that pectin inhibits the inflammatory response by enhancing the AhR-IL22-signal transducer and activator of transcription 3 signaling pathway,which is activated through tryptophan metabolites.

Effects of dietary coenzyme Q10 supplementation during gestation on the embryonic survival and reproductive performance of high‑parity sows

Background Fertility declines in high-parity sows.This study investigated whether parity-dependent declines in embryonic survival and reproductive performance could be restored by dietary coenzyme Q10(CoQ10)supplementation.Methods Two experiments were performed.In Exp.1,30 young sows that had completed their 2nd parity and 30 high-parity sows that had completed their 10^(th)parity,were fed either a control diet(CON)or a CON diet supple-mented with 1 g/kg CoQ10(+CoQ10)from mating until slaughter at day 28 of gestation.In Exp.2,a total of 314 post-weaning sows with two to nine parities were fed the CON or+CoQ10 diets from mating throughout gestation.Results In Exp.1,both young and high-parity sows had a similar number of corpora lutea,but high-parity sows had lower plasma CoQ10 concentrations,down-regulated genes involved with de novo CoQ10 synthesis in the endome-trium tissues,and greater levels of oxidative stress markers in plasma and endometrium tissues.High-parity sows had fewer total embryos and alive embryos,lower embryonic survival,and greater embryo mortality than young sows.Dietary CoQ10 supplementation increased the number of live embryos and the embryonic survival rate to levels simi-lar to those of young sows,as well as lowering the levels of oxidative stress markers.In Exp.2,sows showed a parity-dependent decline in plasma CoQ10 levels,and sows with more than four parities showed a progressive decline in the number of total births,live births,and piglets born effective.Dietary supplementation with CoQ10 increased the number of total births,live births,and born effective,and decreased the intra-litter covariation coefficients and the percentage of sows requiring farrowing assistance during parturition.Conclusions Dietary CoQ10 supplementation can improve the embryonic survival and reproductive performance of gestating sows with high parity,probably by improving the development of uterine function.

Isolation of bacteria from fermented food and grass carp intestine and their efficiencies in improving nutrient value of soybean meal in solid state fermentation

Background: Soybean meal is an excellent and cost-effective protein source; however, its usage is limited in the piglet due to the presence of anti-nutritional factors and the antigens glycinin and β-conglycinin. The objective of the current study was to screen and select for bacteria that can be efficiently adopted to ferment soybean meal in order to solve this problem.Results: Bacteria were isolated from fermented soy foods and the grass carp intestine, and strains selected for high protease, cellulase and amylase activities. The isolated bacteria were characterized as Bacillus cereus, Bacillus subtilis and Bacilus amyloliquefacien, respectively. Fermentation with food-derived Isolate-2 and fish-derived F-9 increased crude protein content by 5.32% and 8.27%, respectively; improved the amino acid profile by increasing certain essential amino acids, broke down larger soy protein to 35 k Da and under, eliminated antigenicity against glycinin and β-conglycinin, and removed raffinose and stachyose in the soybean meal following a 24-h fermentation.Conclusions: Our results suggest these two B. amyloliquefaciens bacteria can efficiently solid state ferment soybean meal and ultimately produce a more utilizable food source for growing healthy piglets.

Dietary protocatechuic acid ameliorates inflammation and up-regulates intestinal tight junction proteins by modulating gut microbiota in LPS-challenged piglets

Background: Weaning is one of the major factors that cause stress and intestinal disease in piglets. Protocatechuic acid(PCA) is an active plant phenolic acid which exists in Chinese herb, Duzhong(Eucommia ulmoides Oliver), and is also considered as the main bioactive metabolite of polyphenol against oxidative stress and inflammation. This study aimed to investigate the effect of PCA on growth performance, intestinal barrier function, and gut microbiota in a weaned piglet model challenged with lipopolysaccharide(LPS).Methods: Thirty-six piglets(Pig Improvement Company line 337 × C48, 28 d of age, 8.87 kg ± 0.11 kg BW) were randomly allocated into 3 treatments and fed with a basal diet(CTL), a diet added 50 mg/kg of aureomycin(AUR), or a diet supplemented with 4000 mg/kg of PCA, respectively. The piglets were challenged with LPS(10 μg/kg BW) on d 14 and d 21 by intraperitoneal injection during the 21-d experiment. Animals(n = 6 from each group) were sacrificed after being anesthetized by sodium pentobarbital at 2 h after the last injection of LPS. The serum was collected for antioxidant indices and inflammatory cytokines analysis, the ileum was harvested for detecting mRNA and protein levels of tight junction proteins by PCR and immunohistochemical staining, and the cecum chyme was collected for intestinal flora analysis using 16 S rRNA gene sequencing.Results: Dietary supplementation of PCA or AUR significantly increased the expression of tight junction proteins including ZO-1 and claudin-1 in intestinal mucosa, and decreased the serum levels of thiobarbituric acid reactive substances(TBARS) and IL-6, as compared with CTL group. In addition, PCA also decreased the serum levels of IL-2 and TNF-α(P < 0.05). Analysis of gut microbiota indicated that PCA increased the Firmicutes/Bacteroidetes ratio(P < 0.05). Spearman's correlation analysis at the genus level revealed that PCA reduced the relative abundance of Prevotella 9, Prevotella 2, Holdemanella, and Ruminococcus torques group(P < 0.05), and increased the relative abundance of Roseburia and Desulfovibrio(P < 0.05), whereas AUR had no significant effect on these bacteria.Conclusions: These results demonstrated that both PCA and AUR had protective effect on oxidative stress, inflammation and intestinal barrier function in piglets challenged with LPS, and PCA potentially exerted the protective function by modulating intestinal flora in a way different from AUR.

The use of Career Growth Scale in Chinese nurses:Validity and reliability

Purpose:To test the validity and reliability of a modified Career Growth Scale(CGS)to assess nurse career growth.Method:A cross-sectional design was used to analyze the use of the CGS to survey 600 fulltime registered nurses from Grade A hospitals in Tianjin.Results:A modified scale we called Career Growth of Nurse Scale(CGNS)is acceptable,valid,and reliable for the evaluation of nurse career growth in Chinese hospitals.This scale measured three main factors(career goal,career capacity,and career opportunity)and showed that nurse career growth differed across age,work seniority,and professional title.Conclusions:A three-dimensional scale of nurse career growth was presented.The results revealed CGNS has good validity and reliability.

Expression of 6 MicroRNAs in Prostate Cancer and Its Significance

OBJECTIVE Numerous microRNAs (miRNAs) are deregulatedin human cancers. The experimental evidence supports thatmiRNAs plays a role in the initiation and progression of humanmalignancies.The present study was undertaken to evaluatethe differential expression of 6 miRNAs as biomarker for earlydetection of prostate cancer, and then to determine whether theexpression profiling of these miRNAs could predict the prognosisof prostate cancer.METHODS The expression profilings of these 6 miRNAs wereinvestigated using the method of locked nucleic acid (LNA)-modified oligonucleotide in situ hybridization (ISH). And thetechnology of tissue microarray (TMA) was employed using theformalin-fixed, paraffin-embedd (FFPE) specimens taken from52 patients with prostate carcinoma (PCa) and 38 patients withbenign prostatic hyperplasia (BPH).RESULTS The rates of positive expression for 6 miRNAs (miR-15b, miR-16, let-7g, miR- 96,miR-182 and miR-183) were 26.92%,15.38%, 15.38%, 67.31%, 61.54% and 71.15% in the specimens ofprostate cancer, and 57.89%, 76.32%, 68.42%, 44.74%, 31.58%,47.37% in the tissues of benign prostatic hyperplasia, respectively.The expressions of all 6 miRNAs between the prostate cancer andbenign prostatic hyperplasia tissues were significantly different(P < 0.05). The positive rate of these 6 miRNAs was significantlyrelated to the Gleason Grading of prostate cancer (P < 0.01). Therewas no significant correlation between the expression of thesemiRNAs and age and the concentration of serum PSA of thepatient (P >0.05). We also found that the expression of miR-15b,miR-96 and miR-182 correlated with clinical stages of tumor (P <0.05). The expression of miR-96 correlated with lobus prostatae oftumor invasion (P < 0.01), but the expressions of the remaining fivemiRNAs were not correlated with that (P >0.05). In addition, theexpression of miR-15b was negatively related to that of miR-96,miR-182 and miR-183, respectively (P < 0.01, r < 0.00).There wasa positive correlation among the expressions of miR-96, miR-182and miR-183 in prostate cancer (P < 0.01, r >0.00). The expressionof miR-16 was positively related to that of miR-let-7g (P < 0.01, r >0.00).CONCLUSION The results suggest that miRNA expressionprofiling could have relevance to the biological and clinicalbehavior of prostate cancer,and they might be importantbiomarkers for early detection and prognostic assessment ofprostate cancer.

Field measurement of wind characteristics and induced tree response during strong storms

Typhoons have caused considerable damage to individual tree and forest ecosystems.To reduce windinduced tree damage and better predict the risk of damage,improving our understanding of wind-tree interactions during strong wind conditions is important.To this purpose,wind characteristics and movements of an individual Betula platyphylla Suk.in a forest stand were monitored during three typhoons(Bavi,Maysak and Haishen).Results revealed that the average wind twists with increasing height,with a large twist gradient within the canopy and a small twist gradient outside the canopy.The maximum wind twist angle was approximately 110°.The disturbance of trees increases the turbulence intensity of the wind field in the canopy.The maximum power of the wind spectra and the turbulence anisotropy of the three turbulence components decrease with increasing height.B.platyphylla did not resonate with the wind in any of the typhoons but responded strongly to gusts near its free vibration peak frequencies.The peak frequency of the mechanical transfer function of B.platyphylla is essentially the same as the peak frequency of the response power spectra.The mechanical transfer func-tion of the wind-induced response of the tree is almost the same as the transfer function of the damped harmonic oscil-lator which has similar characteristics to coniferous trees.

Destruction of the lower crust beneath the North China Craton recorded by granulite and pyroxenite xenoliths

The lower crust beneath the North China Craton(NCC)was transformed during the craton destruction in the Mesozoic,however,the transformation processes are yet to be fully understood.Compositional and geochronological variations of granulite and pyroxenite xenoliths provided insights into the nature of the lower crust before and after the craton destruction.In this study,we summarized the latest results of geochemistry and zircon geochronology coupled with Hf-O isotopes from granulite and pyroxenite xenoliths hosted by Phanerozoic igneous rocks in NCC.Comparing previous studies on the granulite terranes and adakitic rocks of NCC,we aim to discuss the destruction processes of lower crust beneath the NCC.The granulite and pyroxenite xenoliths of NCC were divided into two and three groups,respectively,based on the differences of geochemical features.Group I granulite xenoliths from the NCC have silicic-basic compositions,with metamorphic ferrosilite.The Group I granulite xenoliths show relatively lower Mg#values of pyroxenes and whole-rock than that of the Group II granulite xenoliths,and enrichments of light rare earth elements and Sr-Nd isotopic compositions.Their zircons display Archean-Phanerozoic ages with three peaks of Neoarchean,Paleoproterozoic,and Mesozoic.Generally,Group I granulite xenoliths show close affinities to the granulite terranes of the NCC in terms of the major and trace elements and Sr-Nd isotopic compositions,with a consistent Archean-Proterozoic evolutionary history.However,Group I granulite xenoliths have abundant Phanerozoic zircons with variable Hf isotopic compositions from depleted to enriched,which could be formed by modifications of magma underplating.Therefore,Group I granulite xenoliths represent the modified ancient lower crust beneath the NCC.The Group II granulite and Group III pyroxenite xenoliths from the NCC have similar geochemical features and are basic in compositions,with metamorphic to magmatic orthopyroxenes.The Group II granulite and Group III pyroxenite xenoliths usually show higher MgO and lower incompatible elements compositions in minerals and bulk rocks than that in the granulite terranes and Group I granulite xenoliths,but their Sr-Nd isotopic compositions fall into the fields of granulite terranes and group I granulite xenoliths.Zircons from the Group II granulite and Group III pyroxenite xenoliths are predominantly Phanerozoic with subordinate ArcheanProterozoic ages,and the Hf-O isotopic compositions of zircons are similar to those in the Group I granulite xenoliths.Additionally,the trace element compositions of Group II granulite and Group III pyroxenite xenoliths are complementary to those of the adakitic rocks from the NCC.Furthermore,the similar Sr-Nd and zircon Hf isotopic compositions among Group II granulite and Group III pyroxenite xenoliths and adakitic rocks indicate that they are cognate.Therefore,we suggest that the Group II granulite and Group III pyroxenite xenoliths could be restites left after partial melting of the ancient basic lower crust that produced voluminous adakitic rocks.In contrast,Group I and II pyroxenite xenoliths from the NCC have cumulate and reaction origins,respectively.The Group I and II pyroxenite xenoliths commonly have magmatic enstatite and show higher Mg#values and depleted Sr-Nd isotopic compositions of minerals and bulk rocks relative to that in the granulite and Group III pyroxenite xenoliths.Formation of voluminous Group I pyroxenite cumulates in the crust-mantle transition zones implies extensive magma underplating beneath the NCC during the Mesozoic-Cenozoic,which also provided exotic materials and heat for the reworking of the ancient lower crust.Therefore,the destruction of the lower crust beneath the NCC could result from continuous modifications and remelting of the ancient lower crust triggered by magma underplating.These processes led to not only the transformations of some ancient basic lower crust into granulite and pyroxenite restites but also the compositional modifications of the ancient lower crust.Consequently,the lower crust beneath the NCC showed downward rejuvenation,similar to the lithospheric mantle.

Time-course effects of different fiber-rich ingredients on energy values,microbiota composition and SCFA profile in growing pigs

This study was to investigate time-course effects of different types of dietary fiber on the energy values,fecal microbiota and short-chain fatty acid(SCFA)concentration in growing pigs.A total of 24 barrows(initial body weight,19.8±0.5 kg)were assigned to 4 dietary treatments based on body weight(BW)in a completely randomized design,including a basal diet(CON)and 3 fiber-rich diets replacing corn,soybean meal and soybean oil in the CON diet with 20%sugar beet pulp(SBP),defatted rice bran(DFRB)or soybean hull(SBH),respectively.Fresh feces were sampled on d 7,14 and 21,followed by 5 d total feces and urine collections.The results showed that there were no differences in DE and ME between any of the fiber ingredients on d 7,14 or 21.However,fiber inclusion decreased the DE and ME of the diet(P<0.05)regardless of the time effect.Principal coordinate analysis(PCoA)revealed distinctly different microbial communities on the DFRB diet and SBH diet across different times(P<0.05)and the fecal microbiota of the 4 diet groups demonstrated notably distinct clusters at each time point(P<0.05).With adaptation time increased from 7 to 21 d,cellulose-degrading bacteria and SCFA-producing bacteria(e.g.,Ruminococcaceae_UCG-014,Rikenellaceae_RC9_gut_group and Bifidobacterium)increased in the fiber inclusion diets,and pathogenic genera(e.g.,Streptococcus and Selenomonas)were increased in the basal diet(P<0.05).Furthermore,the gut microbiota of growing pigs adapted more easily and quickly to the SBP diet compared to the DFRB diet,as reflected by the concentration of propionate,butyrate,isovalerate and total SCFA which increased with time for growing pigs fed the DFRB diet(P<0.05).Collectively,our results indicated at least 7 d adaptation was required to evaluate the energy values of fiber-rich ingredients,as the hindgut microbiota of growing pigs may need more time to adapt to a high fiber diet,especially for insoluble dietary fiber.

Differential expression analysis of the broiler tracheal proteins responsible for the immune response and muscle contraction induced by high concentration of ammonia using iTRAQ-coupled 2D LC-MS/MS

Ammonia has been considered the contaminant primarily responsible for respiratory disease in poultry. Even though it can cause tracheal lesions, its adverse effects on the trachea have not been sufficiently studied. The present study investigated tracheal changes in Arbor Acres broilers(Gallus gallus) induced by high concentration of ammonia using isobaric tag for relative and absolute quantification(iTRAQ)-based proteome analysis. In total, 3,706 proteins within false discovery rate of 1% were identified, including 119 significantly differentially expressed proteins. Functional analysis revealed that proteins related to immune response and muscle contraction were significantly enriched. With respect to the immune response, up-regulated proteins(like FGA) were pro-inflammatory, while down-regulated proteins participated in antigen processing and antigen presenting(like MYO1G), immunoglobulin and cathelicidin production(like fowlicidin-2), and immunodeficiency(like PTPRC). Regarding muscle contraction, all differentially expressed proteins(like TPM1) were up-regulated. An over-expression of mucin, which is a common feature of airway disease, was also observed. Additionally, the transcriptional alterations of 6 selected proteins were analyzed by quantitative RT-PCR. Overall, proteomic changes suggested the onset of airway obstruction and diminished host defense in trachea after ammonia exposure. These results may serve as a valuable reference for future interventions against ammonia toxicity.

Spatial distribution and sources of soil heavy metals in the outskirts of Yixing City,Jiangsu Province,China

City outskirts serve as the concentration centers for the pollutants discharged from various sources such as industry,agriculture and transportation.With the acceleration of industrialization and urbanization,the eco-environment of the city outskirts has become a hot spot of public concern.An analysis was conducted in this paper on the soil in the outskirts of Yixing City using frequency distribution functions.The heavy metal sources in this region had been divided into two components,i.e.natural background component and strong human disturbance component.The corresponding interpretation of the distribution pattern and features of heavy metal elements was presented by spatial analysis.The results showed that the strong human disturbance components of Hg,Pb,and Cu accounted for 36.9%, 26.7%,and 23.3%in their contents respectively,which indicated directly the serious effect of human activities on heavy metal contents.Hg and Pb,because of the human disturbance,showed the greatest spatial variability,and human activities intensified the heterogeneity of the spatial distribution.The anisotropic analysis showed the higher organisation of Hg and Zn in the direction of urban-rural transition,which indicated their spatial characteristics with urban-rural transition.Pb displayed distinctive structure in the vertical direction of urban-rural transition,which was largely controlled by highway distribution.Cu content in paddy fields was significantly higher than those of other land-use-types,and the agricultural non-point source pollution played an important role in the distribution pattern of Cu.

Dietary ferulic acid and vanillic acid on inflammation,gut barrier function and growth performance in lipopolysaccharide-challenged piglets

Ferulic acid(FA)and vanillic acid(VA)are considered as major phenolic metabolites of cyanidin 3-glucoside,a polyphenol that widely exists in plants that possess a protective effect against oxidative stress and inflammation in our previous study.This study aimed to investigate the effect of FA and VA on inflammation,gut barrier function,and growth performance in a weaned piglet model challenged with lipopolysaccharide(LPS).Thirty-six piglets(PIC 337×C48,28 d of age)were randomly allocated into 3 treatments with 6 replicate pens(2 piglets per pen).They were fed with a basal diet or a diet containing 4,000 mg/kg of FA or VA.Dietary supplementation of VA significantly increased average daily gain(ADG)(P<0.05).Both FA and VA decreased serum levels of thiobarbituric acid reactive substances(TBARS),interlukin(IL)-1β,IL-2,IL-6,and tumor necrosis factor(TNF)-α(P<0.05),and enhanced the expression of tight junction protein oclaudin(P<0.05).Analysis of gut microbiota indicated that both FA and VA increased the Firmicutes/Bacteroidetes ratio alongside reducing the relative abundance of the Prevotellaceae family including Prevotella 9 and Prevotella 2 genera,but enriched the Lachoiraceaea family including the Lachnospiraceae FCS020 group(P<0.05).Moreover,VA reduced the relative abundance of Prevotella 7 and Prevotella 1 but enriched Lachnospira,Eubacterium eligens group,and Eubacterium xylanophilum group(P<0.05),while FA showed a limited effect on these genera.The results demonstrated that both VA and FA could alleviate inflammation and oxidative stress,but only VA has a significant positive effect on the growth performance of LPS-challenged piglets potentially through modulating gut microbiota.

Effects of ammonia exposure on carcass traits and fatty acid composition of broiler meat

We aimed to study the effects of ammonia on carcass traits, organ indices and fatty acid composition of broilers. Four hundred 21-d-old male Arbor Acres broilers with initial weight 563.52 ± 2.82 g were randomly allotted to 1 of 4 groups treated with ammonia at <3 mg/kg(control),25 ± 3. 50 ± 3, and75 ± 3 mg/kg concentrations. Each group consisted of 4 replicates of 25 birds. Broilers from 21 to 42 d were reared on the net floor in the respiration-metabolism chambers where similar environmental conditions were maintained. At 32 and 42 d of age, carcass traits and organ indices were determined for4 birds per pen. At 42 d of age, fatty acid composition in the breast and thigh muscle of broilers was measured. Results showed as follows: 1) At 32 d, the dressing percentage of broilers exposed to 25 and75 mg/kg ammonia were lower than those in the control group(P < 0.05); eviscerated yield percentage of broilers in the 25 mg/kg ammonia group was also lower(P < 0.05). At 42 d, the dressing percentage of broilers in the ammonia treatments and the thigh muscle percentage of broilers in the 50 and 75 mg/kg ammonia groups were lower(P < 0.05) than those in the control. Breast muscle percentage of broilers exposed to 25 and 50 mg/kg ammonia and eviscerated yield percentage exposed to 50 mg/kg ammonia were lower than those in the control(P < 0.05). 2) The kidney index of broilers(d 32) exposed to ammonia was greater(P < 0.05) than that of the control. At 42 d, hepatic index of broilers exposed to ammonia was increased(P < 0.05), and spleen index was decreased(P < 0.05). 3) At 42 d, stearic(C18:0)and saturated fatty acids(SFA) in the thigh muscle of broilers were higher, while the unsaturated fatty acid:saturated fatty acid(U:F) ratio and unsaturated fatty acid(UFA) were lower in the 50 mg/kg ammonia treatment than in the control group(P < 0.05). In conclusion, ammonia over 25 mg/kg could decline carcass traits and immune organ indices and increase the kidney and hepatic indices. Further,exposure to 50 mg/kg ammonia could also decrease breast and thigh muscle yield percentage while increasing SFA content and decreasing UFA content in the thigh muscle of broilers.

Heat stress-induced mucosal barrier dysfunction is potentially associated with gut microbiota dysbiosis in pigs

Heat stress(HS)can be detrimental to the gut health of swine.Many negative outcomes induced by HS are increasingly recognized as including modulation of intestinal microbiota.In turn,the intestinal microbiota is a unique ecosystem playing a critical role in mediating the host stress response.Therefore,we aimed to characterize gut microbiota of pigs’exposure to short-term HS,to explore a possible link between the intestinal microbiota and HS-related changes,including serum cytokines,oxidation status,and intestinal epithelial barrier function.Our findings showed that HS led to intestinal morphological and integrity changes(villus height,serum diamine oxidase[DAO],serum D-lactate and the relative expressions of tight junction proteins),reduction of serum cytokines(interleukin[IL]-8,IL-12,interferongamma[IFN-g]),and antioxidant activity(higher glutathione[GSH]and malondialdehyde[MDA]content,and lower superoxide dismutase[SOD]).Also,16S rRNA sequencing analysis revealed that although there was no difference in microbial a-diversity,some HS-associated composition differences were revealed in the ileum and cecum,which partly led to an imbalance in the production of short-chain fatty acids including propionate acid and valerate acid.Relevance networks revealed that HS-derived changes in bacterial genera and microbial metabolites,such as Chlamydia,Lactobacillus,Succinivibrio,Bifidobacterium,Lachnoclostridium,and propionic acid,were correlated with oxidative stress,intestinal barrier dysfunction,and inflammation in pigs.Collectively,our observations suggest that intestinal damage induced by HS is probably partly related to the gut microbiota dysbiosis,though the underlying mechanism remains to be fully elucidated.

Chronic heat stress induces the disorder of gut transport and immune function associated with endoplasmic reticulum stress in growing pigs

Although high temperatures influence gut health,data on underlying mechanisms remains scant.Using a pig model,this study performed a global analysis on how chronic heat stress affects the transport and immune function of the gut through transcriptome,proteome,microbial diversity and flow cytometry.A total of 27 pigs with similar body weights were assigned into 3 groups,control(Con)group(23℃),chronic heat stressed(HS)group(33°C),and pair-fed(PF)group,in a controlled environment for 21 days.Our results showed that pigs in the HS group had reduced growth performance and diminished height of ileal villi(P<0.01).Transcriptome and proteome analyses demonstrated notable modification of expression of nutrients and ion transport-related transporters and gut mechanical barrier-related genes by chronic heart stress(P<0.05),suggesting damage of transport functions and the gut barrier.Chronic heat stress-induced endoplasmic reticulum stress also increased the synthesis of misfolded proteins,leading to upregulation of misfolded protein degradation and synthesis,as well as vesicle transport disorder(P<0.05).Energy supply processes were enhanced in the mitochondrion(P<0.05)to maintain biological processes with high energy demands.Furthermore,chronic heat stress activated complement cascade response-related genes and proteins in the gut mucosa(P<0.05).Our flow cytometry assays showed that the proportion of gut lymphocytes(CD4^(+)T cells,T cells,B cells in Peyer’s patch lymphocytes and CD4^(+)CD25^(+)T cells in intraepithelial lymphocytes)were significantly altered in the HS group pigs(P<0.05).In addition,the occurrence of gut microbial dysbiosis in the HS group pigs was characterized by increased potential pathogens(e.g.,Asteroleplasma,Shuttleworthia,Mycoplasma)and suppression of beneficial bacteria(e.g.,Coprococcus and Aeriscardovia),which are associated with gut immune function.Altogether,our data demonstrated that chronic heat stress induced gut transport and immune function disorder associated with endoplasmic reticulum stress in growing pigs.

Aerial ammonia exposure induces the perturbation of the interorgan ammonia disposal and branched-chain amino acid catabolism in growing pigs

Aerial ammonia exposure leads to tissue damage and metabolic dysfunction.However,it is unclear how different organs are coordinated to defend against aerial ammonia exposure.Twenty-four pigs were randomly divided into 4 groups,exposed to 0,10,25 or 35 mg/m^(3) ammonia respectively for 25 d.After above 25 mg/m^(3) ammonia exposure,decreased aspartate(P=0.016),glutamate(P=0.030)and increased ornithine(P=0.002)were found in the ammonia-removing liver,and after high ammonia(35 mg/m^(3))exposure,glutamine synthetase(GS)expression was increased(P=0.012).An increased glutamate(P=0.004)and decreased glutaminase(GLS)expression(P=0.083)were observed in the lungs after high ammonia exposure.There was also an increasing trend of glutamine in the kidneys after high ammonia exposure(P=0.066).For branched-chain amino acid(BCAA)catabolism,high ammonia exposure increased BCAA content in both the lungs and muscle(P<0.05),whereas below 25 mg/m^(3) ammonia exposure increased BCAA only in the lungs(P<0.05).The expression of BCAA transaminase(BCAT1/2)and dehydrogenase complex(BCKDHA/B and DBT)were inhibited to a varying degree in the liver,lungs and muscle after above 25 mg/m^(3) ammonia exposure,especially high ammonia exposure.The expression of BCKDH complex and glutamate-glutamine metabolism-related genes were highly expressed in the liver,followed by the lungs and muscle(P<0.01),whereas the BCAT2 expression was highest in the lungs(P=0.002).Altogether,low ammonia exposure sufficed to evoke the urea cycle to detoxify ammonia in the liver.The process of ammonia removal in the liver and potential ability of the lungs to detoxify ammonia were enhanced with increasing ammonia.Furthermore,high ammonia exposure impaired the BCAA catabolism and decreased the transcripts of the BCAA catabolism-related enzymes,resulting in high BCAA content in extrahepatic tissues.Therefore,with aerial ammonia increasing,an increased urea cycle and glutamine synthesis were ammonia defensive strategies,and high ammonia exposure impaired the BCAA catabolism.

Effects of dietary cellulose levels on the estimation of endogenous amino acid losses and amino acid digestibility for growing pigs

Two experiments were conducted to investigate the effects of dietary cellulose levels on the determination of the ileal endogenous losses(IEL) of amino acids(AA), apparent ileal digestibility(AID) and standardized ileal digestibility(SID) of AA in corn-soybean meal diets for growing pigs. In the first experiment, 28 pigs(BW, 45.1 ± 2.0 kg) that were fitted with simple T-cannulas at the distal ileum were fed 4 nitrogen-free diets consisting of 4 dietary cellulose levels(0, 3%, 6% and 9%) in a randomized complete block design. In the second experiment, 28 pigs(BW, 45.6 ± 2.0 kg) fitted with simple Tcannulas at the distal ileum were fed 4 corn-soybean meal diets consisting of 4 dietary cellulose levels(0,3%, 6% and 9%) in a randomized complete block design. There were 7 replicates per diet with 1 pig as a replicate in each treatment. Both experiments consisted of a 7-d adjustment period and a 2-d ileal digesta collection period on d 8 and 9. Chromic oxide was used as an indigestible marker to calculate IEL and digestibility of AA. The results showed that the IEL of AA for growing pigs was not influenced by dietary cellulose supplementation(P > 0.05). The AID of Thr, Ser, Glu, Cys, Ile, Tyr, Phe, Lys and His decreased with increasing cellulose supplementation levels for pigs fed corn-soybean meal diets(P < 0.05). The SID of Thr, Ser, Cys, Val, Ile, Tyr, Phe, Lys and His decreased with increasing cellulose supplementation levels in corn-soybean meal diets(P < 0.05). In summary, dietary cellulose levels had no effect on the estimation of IEL of AA for growing pigs. The AID and SID of most AA in corn-soybean meal diets decreased with increasing levels of dietary cellulose supplementation.

Evaluation of energy values of high-fiber dietary ingredients with different solubility fed to growing pigs using the difference and regression methods

The objective of this study was to compare the energy values of high-fiber dietary ingredients with different solubility(sugar beet pulp[SBP]and defatted rice bran[DFRB])in growing pigs using the difference and the regression methods.A total of 21 barrows(initial BW,40.5±1.2 kg)were assigned to 3 blocks with BW as a blocking factor,and each block was assigned to a 7×2 incomplete Latin square design with 7 diets and two 13-d experimental periods.The 7 experimental diets consisted of a corn-soybean meal basal diet and 6 additional diets containing 10%,20%,or 30%SBP or DFRB in the basal diet,respectively.Each of the exper-imental periods lasted 12 d,with a 7 d dietary adaptation period followed by 5-d total fecal and urine collection.Results showed that the digestible energy(DE)and metabolizable energy(ME)of the SBP determined by the difference method with different inclusion levels(10%,20%,or 30%)were 2,712 and 2,628 kcal/kg,2,683 and 2,580 kcal/kg,and 2,643 and 2,554 kcal/kg DM basis,respectively.The DE and ME in the DFRB evaluated by the difference method with 3 different inclusion levels were 2,407 and 2,243 kcal/kg,2,687 and 2,598 kcal/kg,and 2,630 and 2,544 kcal/kg DM basis,respectively.Different inclusion levels had no effects on the energy values of each test ingredient estimated by the difference method.The DE and ME of the SBP and the DFRB estimated by the regression method were 2,562 and 2,472 kcal/kg and 2,685 and 2,606 kcal/kg DM basis,respectively.The energy values of each ingredient determined by the regression method were similar to the values estimated by the difference method with the 20%or 30%inclusion level.However,the energy values of the SBP and DFRB estimated by the difference method with the 10%inclusion level were inconsistent with the values determined by the regression method(P<0.05).In conclusion,the regression method was a robust indirect method to evaluate the energy values for high-fiber ingredients with different solubility in growing pigs.If the number of experimental animals was limited,the difference method with a moderate inclusion level(at least 20%)of the test high-fiber ingredient in the basal diet could be applied to substitute the regression method.