Cyanea nozakii,a common jellyfish distributed in offshore China,has a complex trophic relationship with other zooplankton groups.However,few studies have reported the predation rates and prey selection patterns of C.n...Cyanea nozakii,a common jellyfish distributed in offshore China,has a complex trophic relationship with other zooplankton groups.However,few studies have reported the predation rates and prey selection patterns of C.nozakii medusae on different prey items.Research is also lacking on the intraguild predation of Aurelia coerulea(another common bloom jellyfish in offshore China)by C.nozakii.To address the knowledge gaps,the clearance rates of C.nozakii for different prey items,including copepods(small<1000μm and large>1000μm),fish larvae,and gelatinous prey(hydromedusae,A.coerulea ephyrae,and chaetognaths),were measured.The influence of predator size on the clearance rate was also determined.Additionally,we examined the intraguild predation of C.nozakii on A.coerulea medusae.The clearance rates of C.nozakii varied widely with prey organisms,being independent of prey concentrations.Gelatinous organisms,except for chaetognaths,were captured with considerably high efficiency,followed by fish larvae and copepods,indicating the preferential prey selection of gelatinous organisms by C.nozakii.The clearance rate increased linearly with the cross-sectional area of C.nozakii.Body size in medusae may,to some extents,underpin their capacity to capture more prey by increasing the encounter rate and capture success through ontogeny.C.nozakii preyed voraciously on A.coerulea in high feeding efficiency,but the clearance rate decreased with increasing A.coerulea(as prey)size.This phenomenon of intraguild predation suggests a speculative hypothesis of potential population regulation of A.coerulea by C.nozakii.The information regarding the feeding ecology of C.nozakii reported in this study is important for understanding plankton dynamics in marine ecosystems with extensive occurrences of this jellyfish.展开更多
Appropriate feeding practices are important during infancy for good health, growth and development of infants and children. WHO revised its earlier recommendation of Exclusive Breastfeeding (EBF) of infants from 4 to ...Appropriate feeding practices are important during infancy for good health, growth and development of infants and children. WHO revised its earlier recommendation of Exclusive Breastfeeding (EBF) of infants from 4 to 6 months of age to EBF until about 6 months of age, with the addition of complementary foods thereafter. This recommendation confirms that breast milk alone is sufficient to meet infants’ nutritional requirements for the first 6 months of life. The main objective of this study was to investigate the effect of various feeding practices on the Nutritional status of infants 0 - 12-month-old in the Kumba 1 Sub-Division. A descriptive cross-sectional study was conducted from December 2019 to August 2020. A total of 341 nursing mothers and their infants 0 - 12 months of age were recruited. Socio-demographic factors and the different feeding habits of the children were assessed using a semi-structured questionnaire. Nutritional status was assessed using anthropometric measurements. The overall proportion of infants who exclusively breastfed for 6 months was 69.2% and those who were mix-fed were 30.8% in the study area. The overall prevalence of malnutrition in the population was 61.0%. Among the malnourished children, 53.1% were underweight, 19.6% were wasted and 10.0% were stunted. Though not significant, the prevalence of wasting (21.0%) and underweight (58.3%) was higher among Mix-Fed (MF) children when compared to their EBF counterparts. Feeding practices affected the nutritional status of the infants. Underweight and wasting were observed among infants on Complementary Feeding (CF), although some exclusively breast-fed infants were stunted. Hence, nursing mothers should try as much as possible to practice EBF as recommended by WHO and can practice CF when the child is above six months.展开更多
BACKGROUND Gastric cancer is associated with significant undernutrition responsible for an increase in morbidity and mortality after gastrectomy.AIM To evaluate the impact of enteral nutrition by jejunostomy feeding i...BACKGROUND Gastric cancer is associated with significant undernutrition responsible for an increase in morbidity and mortality after gastrectomy.AIM To evaluate the impact of enteral nutrition by jejunostomy feeding in patients undergoing gastrectomy for cancer.METHODS Between 2003 and 2017,all patients undergoing gastrectomy for cancer treatment were included retrospectively.A group with jejunostomy(J+group)and a group without jejunostomy(J-group)were compared.RESULTS Of the 172 patients included,60 received jejunostomy.Preoperatively,the two groups were comparable with respect to the nutritional parameters studied(body mass index,albumin,etc.).In the postoperative period,the J+group lost less weight and albumin:5.74±8.4 vs 9.86±7.5 kg(P=0.07)and 7.2±5.6 vs 14.7±12.7 g/L(P=0.16),respectively.Overall morbidity was 25%in the J+group and 36.6%in the J-group(P=0.12).The J+group had fewer respiratory,infectious,and grade 3 complications:0%vs 5.4%(P=0.09),1.2%vs 9.3%(P=0.03),and 0%vs 4.7%(P=0.05),respectively.The 30-day mortality was 6.7%in the J+group and 6.3%in the J-group(P=0.91).CONCLUSION Jejunostomy feeding after gastrectomy improves nutritional characteristics and decreases postoperative morbidity.A prospective study could confirm our results.展开更多
BACKGROUND Early initiation of enteral feeding is recognized to play a crucial role in improving the outcomes of treatment of acute pancreatitis.However,the method of adminis-tration of enteral nutrition remains debat...BACKGROUND Early initiation of enteral feeding is recognized to play a crucial role in improving the outcomes of treatment of acute pancreatitis.However,the method of adminis-tration of enteral nutrition remains debatable.We present the experience of treating a patient with moderate-severe acute pancreatitis,at high risk of progressing to a severe or fatal condition,using a novel method of selective feeding with duodenal isolation.CASE SUMMARY A 27-year-old female patient presented to the emergency unit of the hospital with a typical manifestation of acute pancreatitis.Despite a conventional treatment,the patient’s condition deteriorated by day 2 of hospitalization.Using an endoscopic approach,a novel catheter PandiCathffwas placed to the duodenum of the patient,isolating its segment between the duodenal bulb and the ligament of Treitz.In the isolated area created,a negative pressure was applied,followed by introduction of early selective enteral feeding.The patient’s condition subsequently improved in a rapid manner,and no complications often associated with moderate-to-severe acute pancreatitis developed.CONCLUSION Within 48 h of starting treatment with the novel method,it can prevent the development of multiple organ failure and,when combined with minimally invasive drainage methods,help prevent infection.展开更多
Medicinal leeches have been utilized in therapy for thousands of years. However, the adaptation physiology between leeches and hosts is not fully understand. To disclose the molecular mechanisms of adaptation between ...Medicinal leeches have been utilized in therapy for thousands of years. However, the adaptation physiology between leeches and hosts is not fully understand. To disclose the molecular mechanisms of adaptation between leech and host, the body transcriptomes of hunger and fed blood-sucking Poecilobdella javanica, Haemadipsa cavatuses, and Hirudo nipponia leeches were obtained by RNA sequencing, after comparison, a stratified unigenes group was obtained, which closely correlated to body distension. In the group, Rfamide receptor decreased significantly (P < 0.05) while serotonin receptor increased significantly (P < 0.05). Moreover, four KEGG (Kyoto Encyclopedia of Genes and Genomes) pathways, including cardiac muscle contraction, complement and coagulation cascades, renin-angiotensin system, and hypertrophic cardiomyopathy were significantly enriched. The unigenes annotation, neuroregulators correlation analysis and induced function of the KEGG pathways, were consistently supported the same result as: vasoconstriction and systole reaction enhance in hunger leeches and vice versa vasodilation and diastole increase in fed leeches, meanwhile, Interspecific comparison and correlative analyses of physiological function showed that the strongest reaction of induced heart failure from four KEGG occur in strongest reaction of systole in hungry P. javanica and in strongest reaction of diastole in fed H. nipponia. Overall, heart failure is likely a physiological function involved in feeding behaviour.展开更多
Aim: Recently, the role of feeding coparenting has gained attention in the child eating research field. The Feeding Coparenting Scale (FCS), a measure of how caregivers interact with their partners when feeding their ...Aim: Recently, the role of feeding coparenting has gained attention in the child eating research field. The Feeding Coparenting Scale (FCS), a measure of how caregivers interact with their partners when feeding their children was developed in the United States in 2019. However, there is no valid and reliable measure to assess feeding coparenting among caregivers of school-aged children in Japan. Therefore, this study aimed to develop a Japanese version of the FCS (FCS-J) questionnaire for caregivers with school-aged children. Methods: This was a web-based cross-sectional survey completed by caregivers of children aged 10-12 years. A preliminary survey using interviews and a web-based survey was conducted and found that the translated items of the FCS into Japanese were understandable to Japanese people. The developed survey was administered to parents of children at an elementary school. The reliability of the survey was assessed using both test-retest reliability and internal consistency analysis. Exploratory factor analysis was used to test construct validity, and known population validity was examined in relation to attributes, marital satisfaction, and feeding tasks. Results: Findings with 135 parents of school-aged children showed good internal reliability and validity of the FCS-J. The mean score for the overall FCS-J score was 46.2 (SD = 6.2), with Cronbach’s α of 0.72. For the subscales, Cronbach’s α ranged from 0.75 to 0.79. In sum, the present study’s results support the three-factor structure of the FCS in Japanese caregivers in Japan. Conclusions: The developed FCS-J was found to have a certain degree of reliability and validity. In this study, a Japanese version of the FCS-J was developed. .展开更多
The aim of the study was to assess feeding practices and the use of lysine and methionine in pig rationing on intensified and semi-intensive pig breeding in the Koudougou and Bobo-Dioulasso areas. To this end, a cross...The aim of the study was to assess feeding practices and the use of lysine and methionine in pig rationing on intensified and semi-intensive pig breeding in the Koudougou and Bobo-Dioulasso areas. To this end, a cross-sectional survey was carried out on 87 breeding in these towns. A Discriminant Factorial Analysis (DFA) confirming a k-means classification of the data collected was used to retain 71 breeding divided into three breeding classes: Class A (32.4% of breeding), Class B (14.08%) and Class C (53.52%). The results show that the majority of pig breeders were men between the ages of 36 and 59. Average herd sizes were 35 ± 28;79 ± 42 and 89 ± 21 pigs for Classes A, B and C respectively. The main breeds of pig found on the breeding were crossbred, Large white, local, Landrace and Duroc. Class A (26.1%), B (30%) and C (15.8%) breeders were familiar with both lysine and methionine. Class A breeders distributed feed staggered (65.2%) and in rations (34.8%). Lysine (13%) and methionine (8.7%) were purchased at 5250 FCFA/kg. Those in class B distributed feed staggered (50%) and in the form of rations (50%), in which they incorporated lysine (30%) and methionine (30%) purchased at a cost of 2500 FCFA/kg and 3000 FCFA/kg respectively. Rationing and staggered feeding were practiced by 23.7% and 76.3% of Class C breeders respectively. Only lysine purchased at 3400 FCFA/kg was incorporated into rations by 10.5% of breeders. The high cost of lysine and methionine was incriminated by Class A (100%), B (33.3%) and C (50%) breeders. In conclusion, intensive pig breeding, the practice of rationing and the incorporation of the amino acids lysine and methionine are of ascending importance from classes C, A to B. The high cost of feedstuffs, particularly lysine and methionine, compromises their use in rations, which could have a negative impact on expected breeding performance. The screening and use of feeds rich in and/or enriched with these amino acids, through the development or adaptation of technologies, could improve the efficiency of rations and the productivity of intensive pig breeding in Burkina Faso.展开更多
Objective:To summarize the evidence of tube feeding intolerance in critically ill children,aiming to provide evidence-based information for clinical nursing staff.Methods:Evidence search was done in Chinese and Englis...Objective:To summarize the evidence of tube feeding intolerance in critically ill children,aiming to provide evidence-based information for clinical nursing staff.Methods:Evidence search was done in Chinese and English databases to guide network and professional associations at home and abroad.The search time limit was from January 2014 to January 2024,nearly 10 years of relevant literature,mainly including guidelines,consensus,expert advice,best practice,evidence summary,system evaluation,and meta-analysis.Literature quality evaluation and evidence extraction were independently performed by two researchers.Results:This paper included 13 articles,including three guidelines,three systematic evaluations,three expert opinions,and four expert consensus.Twenty-six pieces of evidence were summarized from 10 aspects of feeding intolerance definition,team building,nutritional assessment,nutritional preparation,feeding protocol,feeding route,feeding management,pipeline management,gastric residual volume,and drug application.Conclusion:This paper summarized the evidence of tube feeding intolerance in critically ill children,which can provide evidence-based information for clinical practice.The abdominal signs should be closely observed when evaluating feeding intolerance,focusing on the prevention and reduction of feeding interruption.展开更多
Background:Given that the formation of eating behaviors in childhood is largely dependent on parental feeding,it is necessary to consider eating behaviors along with feeding behaviors when exploring child nutrition.Re...Background:Given that the formation of eating behaviors in childhood is largely dependent on parental feeding,it is necessary to consider eating behaviors along with feeding behaviors when exploring child nutrition.Responsive feeding can not only promote the development of self-regulation ability,prevent overweight and obesity,and develop healthy dietary behaviors but also enhance the psychosocial ability,cognitive ability,and language ability of infants.it is of great significance for the growth and development of infants to identify whether the feeding behavior of caregivers is responsive feeding as early as possible.Methods:The progress of the literature summarizes the relevant concepts,evaluation tools,and the relationship between responsive feeding and dietary behavior.Results:This is a fact that China lacks the unified response feeding definition and responsive feeding evaluation tools suitable for homes in China.The relationship between responsive feeding and dietary behavior is in the stage of infancy,and systematic response feeding and dietary behavior have not been formed.Conclusion:It is time to pay attention to the dietary behavior of Chinese children.Intervening measures such as promoting the application of responsive feeding should be actively carry out,accordingly,childhood obesity can be prevented.展开更多
Ultrasonic vibration feeding(UVF) method which can quantitatively feed and precisely deposit fine powder is a potential technique for micro feeding.The excitation sources transmit vibration to capillary though the t...Ultrasonic vibration feeding(UVF) method which can quantitatively feed and precisely deposit fine powder is a potential technique for micro feeding.The excitation sources transmit vibration to capillary though the third medium for most UVF devices.The vibrator is directly touched with the capillary can transmit mechanical energy on the capillary as much as possible,and the powder feeding can be controlled more precise.However,there are few reports about it.A direct UVF system which integrates the function of micro feeding,process observing,and powder forming was developed in this work.In order to analyze the effect of the system factors on feeding,a group of L9(3^3) orthogonal experiments are selected to confirm the effect of level change of factors.The three factors are capillary nozzle diameter,amplitude and signal.The flow rate was stable for each combined factors,and the optimum combination for the minimum flow rate are choosing small capillary,small amplitude,and triangular wave orderly.The whole process of feeding includes start point,middle stage and stop stage.Starting of feeding was synchronized to vibration when the amplitude of capillary nozzle is larger than critical amplitude.Then,the feeding process enters the middle stage,the feeding state is observed by the CCD,and it is very stable in the middle stage.Overflow of feeding can't be eliminated during the stop stage.The features of the deposited powder lines are analyzed; the overflow can be diminished by choosing small capillary and appropriate ratio of the capillary nozzle diameter to the particle size.Chinese characters lattices were deposited to validate the ability of quantitatively feeding and fixed feeding of UVF.Diameters of all powder dots show normal distribution,and more than 60% dots are concentrated from 550 μm to 650 μm,and the average diameter for all the dots is 597 μm.Most dots positions are well approached to their scheduled positions,and the maximum deviation is 0.27 mm.The new direct UVF system is used to implement experiments,which confirms the precise controllable of feeding.According improve the feeding technique,it suits well for rapid prototyping,chemistry,pharmaceutics and many other fields,which require precise measurement and feed minim powder.展开更多
Global food production is expected to double by 2050 for feeding 9 billion people(Godfray et al.2010),but yields had stagnated or even collapsed in 24–39%of crop-growing areas over the period 1961–2008(Ray et al....Global food production is expected to double by 2050 for feeding 9 billion people(Godfray et al.2010),but yields had stagnated or even collapsed in 24–39%of crop-growing areas over the period 1961–2008(Ray et al.2012),展开更多
Background Body phosphorus metabolism exhibits a circadian rhythm over the 24-h daily cycle.The egg laying behavior makes laying hens a very special model for investigating phosphorus circadian rhythms.There is lack o...Background Body phosphorus metabolism exhibits a circadian rhythm over the 24-h daily cycle.The egg laying behavior makes laying hens a very special model for investigating phosphorus circadian rhythms.There is lack of information about the impact of adjusting phosphate feeding regimen according to daily rhythm on the phosphorus homeostasis and bone remodeling of laying hens.Methods and results Two experiments were conducted.In Exp.1,Hy-Line Brown laying hens(n=45)were sampled according the oviposition cycle(at 0,6,12,and 18 h post-oviposition,and at the next oviposition,respectively;n=9 at each time point).Diurnal rhythms of body calcium/phosphorus ingestions and excretions,serum calcium/phosphorus levels,oviduct uterus calcium transporter expressions,and medullary bone(MB)remodeling were illustrated.In Exp.2,two diets with different phosphorus levels(0.32%and 0.14%non-phytate phosphorus(NPP),respectively)were alternately presented to the laying hens.Briefly,four phosphorus feeding regimens in total(each included 6 replicates of 5 hens):(1)fed 0.32%NPP at both 09:00 and 17:00;(2)fed 0.32%NPP at 09:00 and 0.14%NPP at 17:00;(3)fed 0.14%NPP at 09:00 and 0.32%NPP at 17:00;(4)fed 0.14%NPP at both 09:00 and 17:00.As a result,the regimen fed 0.14%NPP at 09:00 and 0.32%NPP at 17:00,which was designed to strengthen intrinsic phosphate circadian rhythms according to the findings in Exp.1,enhanced(P<0.05)MB remodeling(indicated by histological images,serum markers and bone mineralization gene expressions),elevated(P<0.05)oviduct uterus calcium transportation(indicated by transient receptor potential vanilloid 6 protein expression),and subsequently increased(P<0.05)eggshell thickness,eggshell strength,egg specific gravity and eggshell index in laying hens.Conclusions These results underscore the importance of manipulating the sequence of daily phosphorus ingestion,instead of simply controlling dietary phosphate concentrations,in modifying the bone remodeling process.Body phosphorus rhythms will need to be maintained during the daily eggshell calcification cycle.展开更多
The aims of this study were to achieve working stability and continuity of the straw fibre extruder(D200)to improve the transportation efficiency of pretreated straw materials mulch film.Based on a theoretical analysi...The aims of this study were to achieve working stability and continuity of the straw fibre extruder(D200)to improve the transportation efficiency of pretreated straw materials mulch film.Based on a theoretical analysis of wheat straw friction characteristics and the mechanics model of wheat straw transport,a tilting variable-diameter spiral feeding device matched the designed straw fibre extruder(D200-type).Experimental researches were performed by using the orthogonal test method of the L16(45)to obtain the optimal parameter combination.The spiral angle,the speed of the screw shaft and the moisture content of straw raw materials were selected as influencing factors,and feeding efficiency was selected as the objective indicator.The results showed that the spiral angle,the rotating speed of screw shaft and the moisture content of straw raw materials had very significant effects on the feeding efficiency(p<0.01).The order of the extent of the influence of parameters on the feeding efficiency of wheat straw raw materials from high to low was the moisture content,the spiral angle and the speed of screw shaft.When the maximum transfer efficiency per unit time of the inclined spiral feeding device was 1040.8 kg·h-1,the spiral angle was 40?,the speed of screw shaft was 200 r·min-1 and the moisture content was 65%.Verification experiment proved the feasibility of straw fibre extruder designed.展开更多
The feeding habits of the cichlid Tilapia zillii (Gervais) in Lake Kinneret (Israel) were experimentally studied in indoor glass containers (2.5 hrs) and two trials in outdoor 5 m3 tanks (20 - 25 days). The trait of f...The feeding habits of the cichlid Tilapia zillii (Gervais) in Lake Kinneret (Israel) were experimentally studied in indoor glass containers (2.5 hrs) and two trials in outdoor 5 m3 tanks (20 - 25 days). The trait of food particle collection by adult fishes was measured. A survey was carried out in the littoral (0 - 1.0 m deep) zone and fingerlings were sampled by electro-chocker. The gut content of the fingerlings was analyzed. The feeding habits of T. zillii were indicated as planktivorous filtration with more enhancements of small zooplankters (Nauplius, Brachionid rotifers) and fewer of Cladocerans suppressions.展开更多
1 Scope This standard specifies the basic principles and age-specific guidance for complementary feeding, and requirements of complementary feeding preparation for the healthy full-term infants and toddlers from 6 to ...1 Scope This standard specifies the basic principles and age-specific guidance for complementary feeding, and requirements of complementary feeding preparation for the healthy full-term infants and toddlers from 6 to 24 months.This standard is applicable to nutritional guidance for complementary foods supplements for the infants and toddlers from 6 to 24 months.展开更多
Three experimental groups with different feeding frequencies,different feeding rates and compensatory feeding were set up to study their effects on the growth of Micropterus salmoides.The results showed that different...Three experimental groups with different feeding frequencies,different feeding rates and compensatory feeding were set up to study their effects on the growth of Micropterus salmoides.The results showed that different feeding rates of 2%,3%and 4%had no significant effects on the growth of M.salmoides.Therefore,before the individual weight of 50 g,the fish could be fed with a feeding rate of 4%,which could be gradually decreased to 2%in the later period.Under the condition of relatively fixed feeding rate,different feeding frequencies had an impact on the growth of M.salmoides.Under the conditions of suitable water temperature,it is reasonable to feed twice daily.The experimental fish fed for 5 d and then deprived of feed for 1 d showed fully compensatory growth,and there were no significant differences in weight gain rate,daily weight gain and specific growth rate compared with the continuous feeding group(P>0.05).Therefore,according to the feeding conditions of fish in the breeding process,stopping feeding for 1 d every 5 d could save feed and labor and improve breeding efficiency.展开更多
Substrate is an important abiotic factor for burrowing shellfish,as it not only provides them with shelter,but also impose significant effect on their physiological metabolism.However,the physiological responses of bu...Substrate is an important abiotic factor for burrowing shellfish,as it not only provides them with shelter,but also impose significant effect on their physiological metabolism.However,the physiological responses of burrowing clams within various substrates get less attention due to difficulty in carrying out physiological tests in buried conditions.Consequently,this study investigated the burrowing behavior,feeding physiology and energy budget of Paphia undulata,which is an important aquaculture bivalve species in south China.The clams were exposed to mud and sand substrates with variable physical properties in the laboratory,to determine the suitable substrate conditions for this species.The results showed that the percentage of burrowing clams,digging index,burrowing time,burrowing depth and scope for growth(SFG)were higher in mud substrates with≥40%water content.Likewise,burrowing percentage,digging index,and burrowing depths were higher in substrates with≤40%sand content.Moreover,the burrowing depth had significant effect on the feeding physiology and SFG of P.undulata as clams burrowed at 6.3±1.8 cm had higher clearance rates and SFG as compared to other buried depths.This study further revealed that low water content in the sediment inhibited physiological performances of P.undulata by impairing feeding or absorption,hence reducing the SFG.In conclusion,mud substrate with≥40%water content or with≤40%sand content is suitable for proper burrowing and growth of P.undulata.Our findings therefore provide fundamental knowledge that will be applicable in the improvement of bottom aquaculture and conservation of P.undulata.展开更多
Sea cucumber(Apostichopus japonicus)is an excellent model for investigating effects of bottom-dwellers on carbon mig-ration and transformation.However,the molecular mechanism of respiratory metabolism process variatio...Sea cucumber(Apostichopus japonicus)is an excellent model for investigating effects of bottom-dwellers on carbon mig-ration and transformation.However,the molecular mechanism of respiratory metabolism process variation caused by feeding rations is poorly understood.In this study,treatment groups set as 1%(about 0.63g),3%,and 7%of total body weight(named F1,F3 and F7 groups respectively).The potential molecular mechanisms behind the functions of respiratory tree and body wall were investigated by RNA-Seq.A total of 52411 expressed genes were identified from 89342 expressed transcripts.The results showed 759,254 and 334 genes were up-regulated,and 334,445 and 992 genes were down-regulated in respiratory tree of F1 vs.F3,F1 vs.F7 and F3 vs.F7,respectively.Meanwhile,2070,1601 and 896 genes were up-regulated,and 1303,1337 and 1144 genes were down-regulated in body wall between F1 vs.F3,F1 vs.F7 and F3 vs.F7,respectively.Differentially expressed genes were enriched in salivary secretion and ECM-receptor interaction pathways in respiratory tree,and in various types of N-glycan biosynthesis,ribosome and sphingolipid metabolism pathways in body wall.These results suggested respiratory tree and body wall were involved in activation of respiratory metabolisms in response to different feeding rations.Our research provided valuable knowledge for physiological differences in res-piratory metabolism.展开更多
Cladocera are filter feeders abundant in freshwaters,which consume phytoplankton particles in wide size and taxonomic ranges.The ability of cladocerans to control phytoplankton abundance by grazing is determined by va...Cladocera are filter feeders abundant in freshwaters,which consume phytoplankton particles in wide size and taxonomic ranges.The ability of cladocerans to control phytoplankton abundance by grazing is determined by various factors including the characteristics of phytoplankton.Freshwater salinization may reduce the strength of top-down grazing control of phytoplankton because of the detrimental effects of salinity on the grazing intensity of zooplankters.We performed grazing experiments with two species of Cladocera of different body lengths to test their ability to graze on phytoplankton in natural waters differing in salinity and size and taxonomic composition of food particles.Grazing experiments demonstrated that the grazing rate was mostly controlled by the abundance of phytoplankton in the medium.The grazing rate was reduced at salinity ca.above 3 g/L of NaCl in the medium.The lower grazing rate was observed in the medium with larger phytoplankton particles.Both species predominantly consumed phytoplankton particles with a diameter of 6-12μm,which may shift the size distribution of phytoplankton towards a larger average diameter of particles.The taxon-specific feeding was also observed,as both species predominantly consumed diatom algae.Thus,we found that because of grazing,the size and taxonomic characteristics of phytoplankton are shifted towards a less edible community.The detrimental effect of elevated salinity on grazing rate supports growing concern about freshwater salinization negatively affecting water quality,particularly reducing top-down grazing control of phytoplankton.展开更多
Fodder production in arid rangelands has been traditionally considered as the main source of nutrition for livestock.However,the production of these fodder may be influenced by some socio-economic and climatic factors...Fodder production in arid rangelands has been traditionally considered as the main source of nutrition for livestock.However,the production of these fodder may be influenced by some socio-economic and climatic factors.This study aims to identify the various rangeland use forms and determine the types of livestock feeding system in the El Ouara rangelands of Ben guarden District in southern Tunisia by analysing the importance of supplemental feeding and main determinants of this practice.Data were collected by a survey that targeted a sample of 50 breeders in the El Ouara rangelands.Descriptive statistics and binary logistic regression were used to analyse the data.The results showed that there are two types of association practiced by breeders:“Cherka”association practiced by 10.00% of breeders and cash payment association practiced by 53.00% of breeders.Then,transhumance,sedentary,and semi-urban forms are the main ways in which breeders use the rangelands.There are four livestock feeding systems in the El Ouara rangelands being used to feed livestock:natural rangeland,rangeland-based,mixed,and concentrate-based feeding systems.Supplemental feeding has become fundamental for the livestock feeding system in the El Ouara rangelands.The breeders with the largest camel size still use the natural rangeland feeding system,while the breeders who have the largest herd size practice the mixed feeding system.The logistic regression results reveal that breeder age,cereal area,herd size,migrant remittance,second activity,and agricultural development group membership can significantly impact the supplemental feeding.In summary,this study can help policy-makers plan innovative practices based on climatic change,ensure the sustainability of livestock feeding system,and make effective decisions for local development.展开更多
基金the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDA19060203)the National Natural Science Foundation of China(Nos.42076166,42130411)+4 种基金the Natural Science Foundation of Shandong Province(No.ZR2021QD061)the CAS-CSIRO Project Fund(No.GJHZ1888)the Mount Tai Scholar Climbing Plan to Song SUNthe Innovation Team of Fishery Resources and Ecology in the Yellow Sea and Bohai Sea(No.2020TD01)the Hainan Province Basic and Applied Basic Research Program(Natural Science Field)High-Level Talent Project(No.2019RC353)。
文摘Cyanea nozakii,a common jellyfish distributed in offshore China,has a complex trophic relationship with other zooplankton groups.However,few studies have reported the predation rates and prey selection patterns of C.nozakii medusae on different prey items.Research is also lacking on the intraguild predation of Aurelia coerulea(another common bloom jellyfish in offshore China)by C.nozakii.To address the knowledge gaps,the clearance rates of C.nozakii for different prey items,including copepods(small<1000μm and large>1000μm),fish larvae,and gelatinous prey(hydromedusae,A.coerulea ephyrae,and chaetognaths),were measured.The influence of predator size on the clearance rate was also determined.Additionally,we examined the intraguild predation of C.nozakii on A.coerulea medusae.The clearance rates of C.nozakii varied widely with prey organisms,being independent of prey concentrations.Gelatinous organisms,except for chaetognaths,were captured with considerably high efficiency,followed by fish larvae and copepods,indicating the preferential prey selection of gelatinous organisms by C.nozakii.The clearance rate increased linearly with the cross-sectional area of C.nozakii.Body size in medusae may,to some extents,underpin their capacity to capture more prey by increasing the encounter rate and capture success through ontogeny.C.nozakii preyed voraciously on A.coerulea in high feeding efficiency,but the clearance rate decreased with increasing A.coerulea(as prey)size.This phenomenon of intraguild predation suggests a speculative hypothesis of potential population regulation of A.coerulea by C.nozakii.The information regarding the feeding ecology of C.nozakii reported in this study is important for understanding plankton dynamics in marine ecosystems with extensive occurrences of this jellyfish.
文摘Appropriate feeding practices are important during infancy for good health, growth and development of infants and children. WHO revised its earlier recommendation of Exclusive Breastfeeding (EBF) of infants from 4 to 6 months of age to EBF until about 6 months of age, with the addition of complementary foods thereafter. This recommendation confirms that breast milk alone is sufficient to meet infants’ nutritional requirements for the first 6 months of life. The main objective of this study was to investigate the effect of various feeding practices on the Nutritional status of infants 0 - 12-month-old in the Kumba 1 Sub-Division. A descriptive cross-sectional study was conducted from December 2019 to August 2020. A total of 341 nursing mothers and their infants 0 - 12 months of age were recruited. Socio-demographic factors and the different feeding habits of the children were assessed using a semi-structured questionnaire. Nutritional status was assessed using anthropometric measurements. The overall proportion of infants who exclusively breastfed for 6 months was 69.2% and those who were mix-fed were 30.8% in the study area. The overall prevalence of malnutrition in the population was 61.0%. Among the malnourished children, 53.1% were underweight, 19.6% were wasted and 10.0% were stunted. Though not significant, the prevalence of wasting (21.0%) and underweight (58.3%) was higher among Mix-Fed (MF) children when compared to their EBF counterparts. Feeding practices affected the nutritional status of the infants. Underweight and wasting were observed among infants on Complementary Feeding (CF), although some exclusively breast-fed infants were stunted. Hence, nursing mothers should try as much as possible to practice EBF as recommended by WHO and can practice CF when the child is above six months.
文摘BACKGROUND Gastric cancer is associated with significant undernutrition responsible for an increase in morbidity and mortality after gastrectomy.AIM To evaluate the impact of enteral nutrition by jejunostomy feeding in patients undergoing gastrectomy for cancer.METHODS Between 2003 and 2017,all patients undergoing gastrectomy for cancer treatment were included retrospectively.A group with jejunostomy(J+group)and a group without jejunostomy(J-group)were compared.RESULTS Of the 172 patients included,60 received jejunostomy.Preoperatively,the two groups were comparable with respect to the nutritional parameters studied(body mass index,albumin,etc.).In the postoperative period,the J+group lost less weight and albumin:5.74±8.4 vs 9.86±7.5 kg(P=0.07)and 7.2±5.6 vs 14.7±12.7 g/L(P=0.16),respectively.Overall morbidity was 25%in the J+group and 36.6%in the J-group(P=0.12).The J+group had fewer respiratory,infectious,and grade 3 complications:0%vs 5.4%(P=0.09),1.2%vs 9.3%(P=0.03),and 0%vs 4.7%(P=0.05),respectively.The 30-day mortality was 6.7%in the J+group and 6.3%in the J-group(P=0.91).CONCLUSION Jejunostomy feeding after gastrectomy improves nutritional characteristics and decreases postoperative morbidity.A prospective study could confirm our results.
文摘BACKGROUND Early initiation of enteral feeding is recognized to play a crucial role in improving the outcomes of treatment of acute pancreatitis.However,the method of adminis-tration of enteral nutrition remains debatable.We present the experience of treating a patient with moderate-severe acute pancreatitis,at high risk of progressing to a severe or fatal condition,using a novel method of selective feeding with duodenal isolation.CASE SUMMARY A 27-year-old female patient presented to the emergency unit of the hospital with a typical manifestation of acute pancreatitis.Despite a conventional treatment,the patient’s condition deteriorated by day 2 of hospitalization.Using an endoscopic approach,a novel catheter PandiCathffwas placed to the duodenum of the patient,isolating its segment between the duodenal bulb and the ligament of Treitz.In the isolated area created,a negative pressure was applied,followed by introduction of early selective enteral feeding.The patient’s condition subsequently improved in a rapid manner,and no complications often associated with moderate-to-severe acute pancreatitis developed.CONCLUSION Within 48 h of starting treatment with the novel method,it can prevent the development of multiple organ failure and,when combined with minimally invasive drainage methods,help prevent infection.
文摘Medicinal leeches have been utilized in therapy for thousands of years. However, the adaptation physiology between leeches and hosts is not fully understand. To disclose the molecular mechanisms of adaptation between leech and host, the body transcriptomes of hunger and fed blood-sucking Poecilobdella javanica, Haemadipsa cavatuses, and Hirudo nipponia leeches were obtained by RNA sequencing, after comparison, a stratified unigenes group was obtained, which closely correlated to body distension. In the group, Rfamide receptor decreased significantly (P < 0.05) while serotonin receptor increased significantly (P < 0.05). Moreover, four KEGG (Kyoto Encyclopedia of Genes and Genomes) pathways, including cardiac muscle contraction, complement and coagulation cascades, renin-angiotensin system, and hypertrophic cardiomyopathy were significantly enriched. The unigenes annotation, neuroregulators correlation analysis and induced function of the KEGG pathways, were consistently supported the same result as: vasoconstriction and systole reaction enhance in hunger leeches and vice versa vasodilation and diastole increase in fed leeches, meanwhile, Interspecific comparison and correlative analyses of physiological function showed that the strongest reaction of induced heart failure from four KEGG occur in strongest reaction of systole in hungry P. javanica and in strongest reaction of diastole in fed H. nipponia. Overall, heart failure is likely a physiological function involved in feeding behaviour.
文摘Aim: Recently, the role of feeding coparenting has gained attention in the child eating research field. The Feeding Coparenting Scale (FCS), a measure of how caregivers interact with their partners when feeding their children was developed in the United States in 2019. However, there is no valid and reliable measure to assess feeding coparenting among caregivers of school-aged children in Japan. Therefore, this study aimed to develop a Japanese version of the FCS (FCS-J) questionnaire for caregivers with school-aged children. Methods: This was a web-based cross-sectional survey completed by caregivers of children aged 10-12 years. A preliminary survey using interviews and a web-based survey was conducted and found that the translated items of the FCS into Japanese were understandable to Japanese people. The developed survey was administered to parents of children at an elementary school. The reliability of the survey was assessed using both test-retest reliability and internal consistency analysis. Exploratory factor analysis was used to test construct validity, and known population validity was examined in relation to attributes, marital satisfaction, and feeding tasks. Results: Findings with 135 parents of school-aged children showed good internal reliability and validity of the FCS-J. The mean score for the overall FCS-J score was 46.2 (SD = 6.2), with Cronbach’s α of 0.72. For the subscales, Cronbach’s α ranged from 0.75 to 0.79. In sum, the present study’s results support the three-factor structure of the FCS in Japanese caregivers in Japan. Conclusions: The developed FCS-J was found to have a certain degree of reliability and validity. In this study, a Japanese version of the FCS-J was developed. .
文摘The aim of the study was to assess feeding practices and the use of lysine and methionine in pig rationing on intensified and semi-intensive pig breeding in the Koudougou and Bobo-Dioulasso areas. To this end, a cross-sectional survey was carried out on 87 breeding in these towns. A Discriminant Factorial Analysis (DFA) confirming a k-means classification of the data collected was used to retain 71 breeding divided into three breeding classes: Class A (32.4% of breeding), Class B (14.08%) and Class C (53.52%). The results show that the majority of pig breeders were men between the ages of 36 and 59. Average herd sizes were 35 ± 28;79 ± 42 and 89 ± 21 pigs for Classes A, B and C respectively. The main breeds of pig found on the breeding were crossbred, Large white, local, Landrace and Duroc. Class A (26.1%), B (30%) and C (15.8%) breeders were familiar with both lysine and methionine. Class A breeders distributed feed staggered (65.2%) and in rations (34.8%). Lysine (13%) and methionine (8.7%) were purchased at 5250 FCFA/kg. Those in class B distributed feed staggered (50%) and in the form of rations (50%), in which they incorporated lysine (30%) and methionine (30%) purchased at a cost of 2500 FCFA/kg and 3000 FCFA/kg respectively. Rationing and staggered feeding were practiced by 23.7% and 76.3% of Class C breeders respectively. Only lysine purchased at 3400 FCFA/kg was incorporated into rations by 10.5% of breeders. The high cost of lysine and methionine was incriminated by Class A (100%), B (33.3%) and C (50%) breeders. In conclusion, intensive pig breeding, the practice of rationing and the incorporation of the amino acids lysine and methionine are of ascending importance from classes C, A to B. The high cost of feedstuffs, particularly lysine and methionine, compromises their use in rations, which could have a negative impact on expected breeding performance. The screening and use of feeds rich in and/or enriched with these amino acids, through the development or adaptation of technologies, could improve the efficiency of rations and the productivity of intensive pig breeding in Burkina Faso.
文摘Objective:To summarize the evidence of tube feeding intolerance in critically ill children,aiming to provide evidence-based information for clinical nursing staff.Methods:Evidence search was done in Chinese and English databases to guide network and professional associations at home and abroad.The search time limit was from January 2014 to January 2024,nearly 10 years of relevant literature,mainly including guidelines,consensus,expert advice,best practice,evidence summary,system evaluation,and meta-analysis.Literature quality evaluation and evidence extraction were independently performed by two researchers.Results:This paper included 13 articles,including three guidelines,three systematic evaluations,three expert opinions,and four expert consensus.Twenty-six pieces of evidence were summarized from 10 aspects of feeding intolerance definition,team building,nutritional assessment,nutritional preparation,feeding protocol,feeding route,feeding management,pipeline management,gastric residual volume,and drug application.Conclusion:This paper summarized the evidence of tube feeding intolerance in critically ill children,which can provide evidence-based information for clinical practice.The abdominal signs should be closely observed when evaluating feeding intolerance,focusing on the prevention and reduction of feeding interruption.
文摘Background:Given that the formation of eating behaviors in childhood is largely dependent on parental feeding,it is necessary to consider eating behaviors along with feeding behaviors when exploring child nutrition.Responsive feeding can not only promote the development of self-regulation ability,prevent overweight and obesity,and develop healthy dietary behaviors but also enhance the psychosocial ability,cognitive ability,and language ability of infants.it is of great significance for the growth and development of infants to identify whether the feeding behavior of caregivers is responsive feeding as early as possible.Methods:The progress of the literature summarizes the relevant concepts,evaluation tools,and the relationship between responsive feeding and dietary behavior.Results:This is a fact that China lacks the unified response feeding definition and responsive feeding evaluation tools suitable for homes in China.The relationship between responsive feeding and dietary behavior is in the stage of infancy,and systematic response feeding and dietary behavior have not been formed.Conclusion:It is time to pay attention to the dietary behavior of Chinese children.Intervening measures such as promoting the application of responsive feeding should be actively carry out,accordingly,childhood obesity can be prevented.
基金supported by National Hi-tech Research and Development Program of China (863 Program, Grant No. 2008AA03A238)National Natural Science Foundation of China (Grant No. 51005186)Foundation for the Author of National Excellent Doctoral Dissertation of China (Grant No. 2007B39)
文摘Ultrasonic vibration feeding(UVF) method which can quantitatively feed and precisely deposit fine powder is a potential technique for micro feeding.The excitation sources transmit vibration to capillary though the third medium for most UVF devices.The vibrator is directly touched with the capillary can transmit mechanical energy on the capillary as much as possible,and the powder feeding can be controlled more precise.However,there are few reports about it.A direct UVF system which integrates the function of micro feeding,process observing,and powder forming was developed in this work.In order to analyze the effect of the system factors on feeding,a group of L9(3^3) orthogonal experiments are selected to confirm the effect of level change of factors.The three factors are capillary nozzle diameter,amplitude and signal.The flow rate was stable for each combined factors,and the optimum combination for the minimum flow rate are choosing small capillary,small amplitude,and triangular wave orderly.The whole process of feeding includes start point,middle stage and stop stage.Starting of feeding was synchronized to vibration when the amplitude of capillary nozzle is larger than critical amplitude.Then,the feeding process enters the middle stage,the feeding state is observed by the CCD,and it is very stable in the middle stage.Overflow of feeding can't be eliminated during the stop stage.The features of the deposited powder lines are analyzed; the overflow can be diminished by choosing small capillary and appropriate ratio of the capillary nozzle diameter to the particle size.Chinese characters lattices were deposited to validate the ability of quantitatively feeding and fixed feeding of UVF.Diameters of all powder dots show normal distribution,and more than 60% dots are concentrated from 550 μm to 650 μm,and the average diameter for all the dots is 597 μm.Most dots positions are well approached to their scheduled positions,and the maximum deviation is 0.27 mm.The new direct UVF system is used to implement experiments,which confirms the precise controllable of feeding.According improve the feeding technique,it suits well for rapid prototyping,chemistry,pharmaceutics and many other fields,which require precise measurement and feed minim powder.
文摘Global food production is expected to double by 2050 for feeding 9 billion people(Godfray et al.2010),but yields had stagnated or even collapsed in 24–39%of crop-growing areas over the period 1961–2008(Ray et al.2012),
基金supported by National Natural Science Foundation of China (32172759)Shaanxi Provincial Science and Technology Department (2022QFY11-05,2021KJXX-97,2021TD-30).
文摘Background Body phosphorus metabolism exhibits a circadian rhythm over the 24-h daily cycle.The egg laying behavior makes laying hens a very special model for investigating phosphorus circadian rhythms.There is lack of information about the impact of adjusting phosphate feeding regimen according to daily rhythm on the phosphorus homeostasis and bone remodeling of laying hens.Methods and results Two experiments were conducted.In Exp.1,Hy-Line Brown laying hens(n=45)were sampled according the oviposition cycle(at 0,6,12,and 18 h post-oviposition,and at the next oviposition,respectively;n=9 at each time point).Diurnal rhythms of body calcium/phosphorus ingestions and excretions,serum calcium/phosphorus levels,oviduct uterus calcium transporter expressions,and medullary bone(MB)remodeling were illustrated.In Exp.2,two diets with different phosphorus levels(0.32%and 0.14%non-phytate phosphorus(NPP),respectively)were alternately presented to the laying hens.Briefly,four phosphorus feeding regimens in total(each included 6 replicates of 5 hens):(1)fed 0.32%NPP at both 09:00 and 17:00;(2)fed 0.32%NPP at 09:00 and 0.14%NPP at 17:00;(3)fed 0.14%NPP at 09:00 and 0.32%NPP at 17:00;(4)fed 0.14%NPP at both 09:00 and 17:00.As a result,the regimen fed 0.14%NPP at 09:00 and 0.32%NPP at 17:00,which was designed to strengthen intrinsic phosphate circadian rhythms according to the findings in Exp.1,enhanced(P<0.05)MB remodeling(indicated by histological images,serum markers and bone mineralization gene expressions),elevated(P<0.05)oviduct uterus calcium transportation(indicated by transient receptor potential vanilloid 6 protein expression),and subsequently increased(P<0.05)eggshell thickness,eggshell strength,egg specific gravity and eggshell index in laying hens.Conclusions These results underscore the importance of manipulating the sequence of daily phosphorus ingestion,instead of simply controlling dietary phosphate concentrations,in modifying the bone remodeling process.Body phosphorus rhythms will need to be maintained during the daily eggshell calcification cycle.
基金Supported by Integrated Research and Demonstration of Chemical Fertilizer and Pesticide Reduction Technology for Soybean in Northeast China(2018YFD0201004)Funding from the Construction of Modern Agricultural Industrial Technology System(GARS-04)。
文摘The aims of this study were to achieve working stability and continuity of the straw fibre extruder(D200)to improve the transportation efficiency of pretreated straw materials mulch film.Based on a theoretical analysis of wheat straw friction characteristics and the mechanics model of wheat straw transport,a tilting variable-diameter spiral feeding device matched the designed straw fibre extruder(D200-type).Experimental researches were performed by using the orthogonal test method of the L16(45)to obtain the optimal parameter combination.The spiral angle,the speed of the screw shaft and the moisture content of straw raw materials were selected as influencing factors,and feeding efficiency was selected as the objective indicator.The results showed that the spiral angle,the rotating speed of screw shaft and the moisture content of straw raw materials had very significant effects on the feeding efficiency(p<0.01).The order of the extent of the influence of parameters on the feeding efficiency of wheat straw raw materials from high to low was the moisture content,the spiral angle and the speed of screw shaft.When the maximum transfer efficiency per unit time of the inclined spiral feeding device was 1040.8 kg·h-1,the spiral angle was 40?,the speed of screw shaft was 200 r·min-1 and the moisture content was 65%.Verification experiment proved the feasibility of straw fibre extruder designed.
文摘The feeding habits of the cichlid Tilapia zillii (Gervais) in Lake Kinneret (Israel) were experimentally studied in indoor glass containers (2.5 hrs) and two trials in outdoor 5 m3 tanks (20 - 25 days). The trait of food particle collection by adult fishes was measured. A survey was carried out in the littoral (0 - 1.0 m deep) zone and fingerlings were sampled by electro-chocker. The gut content of the fingerlings was analyzed. The feeding habits of T. zillii were indicated as planktivorous filtration with more enhancements of small zooplankters (Nauplius, Brachionid rotifers) and fewer of Cladocerans suppressions.
文摘1 Scope This standard specifies the basic principles and age-specific guidance for complementary feeding, and requirements of complementary feeding preparation for the healthy full-term infants and toddlers from 6 to 24 months.This standard is applicable to nutritional guidance for complementary foods supplements for the infants and toddlers from 6 to 24 months.
基金Supported by Key R&D Program of Hubei Province(2022BBA0058)。
文摘Three experimental groups with different feeding frequencies,different feeding rates and compensatory feeding were set up to study their effects on the growth of Micropterus salmoides.The results showed that different feeding rates of 2%,3%and 4%had no significant effects on the growth of M.salmoides.Therefore,before the individual weight of 50 g,the fish could be fed with a feeding rate of 4%,which could be gradually decreased to 2%in the later period.Under the condition of relatively fixed feeding rate,different feeding frequencies had an impact on the growth of M.salmoides.Under the conditions of suitable water temperature,it is reasonable to feed twice daily.The experimental fish fed for 5 d and then deprived of feed for 1 d showed fully compensatory growth,and there were no significant differences in weight gain rate,daily weight gain and specific growth rate compared with the continuous feeding group(P>0.05).Therefore,according to the feeding conditions of fish in the breeding process,stopping feeding for 1 d every 5 d could save feed and labor and improve breeding efficiency.
基金Supported by the Guangxi Science and Technology Base and Talent Special Project (No.AD23026114)。
文摘Substrate is an important abiotic factor for burrowing shellfish,as it not only provides them with shelter,but also impose significant effect on their physiological metabolism.However,the physiological responses of burrowing clams within various substrates get less attention due to difficulty in carrying out physiological tests in buried conditions.Consequently,this study investigated the burrowing behavior,feeding physiology and energy budget of Paphia undulata,which is an important aquaculture bivalve species in south China.The clams were exposed to mud and sand substrates with variable physical properties in the laboratory,to determine the suitable substrate conditions for this species.The results showed that the percentage of burrowing clams,digging index,burrowing time,burrowing depth and scope for growth(SFG)were higher in mud substrates with≥40%water content.Likewise,burrowing percentage,digging index,and burrowing depths were higher in substrates with≤40%sand content.Moreover,the burrowing depth had significant effect on the feeding physiology and SFG of P.undulata as clams burrowed at 6.3±1.8 cm had higher clearance rates and SFG as compared to other buried depths.This study further revealed that low water content in the sediment inhibited physiological performances of P.undulata by impairing feeding or absorption,hence reducing the SFG.In conclusion,mud substrate with≥40%water content or with≤40%sand content is suitable for proper burrowing and growth of P.undulata.Our findings therefore provide fundamental knowledge that will be applicable in the improvement of bottom aquaculture and conservation of P.undulata.
基金supported by the National Natural Science Foundation of China(No.31672657).
文摘Sea cucumber(Apostichopus japonicus)is an excellent model for investigating effects of bottom-dwellers on carbon mig-ration and transformation.However,the molecular mechanism of respiratory metabolism process variation caused by feeding rations is poorly understood.In this study,treatment groups set as 1%(about 0.63g),3%,and 7%of total body weight(named F1,F3 and F7 groups respectively).The potential molecular mechanisms behind the functions of respiratory tree and body wall were investigated by RNA-Seq.A total of 52411 expressed genes were identified from 89342 expressed transcripts.The results showed 759,254 and 334 genes were up-regulated,and 334,445 and 992 genes were down-regulated in respiratory tree of F1 vs.F3,F1 vs.F7 and F3 vs.F7,respectively.Meanwhile,2070,1601 and 896 genes were up-regulated,and 1303,1337 and 1144 genes were down-regulated in body wall between F1 vs.F3,F1 vs.F7 and F3 vs.F7,respectively.Differentially expressed genes were enriched in salivary secretion and ECM-receptor interaction pathways in respiratory tree,and in various types of N-glycan biosynthesis,ribosome and sphingolipid metabolism pathways in body wall.These results suggested respiratory tree and body wall were involved in activation of respiratory metabolisms in response to different feeding rations.Our research provided valuable knowledge for physiological differences in res-piratory metabolism.
基金supported by the State Assignment of the Ministry of Science and Higher Education of the RF(No.0287-2021-0019).
文摘Cladocera are filter feeders abundant in freshwaters,which consume phytoplankton particles in wide size and taxonomic ranges.The ability of cladocerans to control phytoplankton abundance by grazing is determined by various factors including the characteristics of phytoplankton.Freshwater salinization may reduce the strength of top-down grazing control of phytoplankton because of the detrimental effects of salinity on the grazing intensity of zooplankters.We performed grazing experiments with two species of Cladocera of different body lengths to test their ability to graze on phytoplankton in natural waters differing in salinity and size and taxonomic composition of food particles.Grazing experiments demonstrated that the grazing rate was mostly controlled by the abundance of phytoplankton in the medium.The grazing rate was reduced at salinity ca.above 3 g/L of NaCl in the medium.The lower grazing rate was observed in the medium with larger phytoplankton particles.Both species predominantly consumed phytoplankton particles with a diameter of 6-12μm,which may shift the size distribution of phytoplankton towards a larger average diameter of particles.The taxon-specific feeding was also observed,as both species predominantly consumed diatom algae.Thus,we found that because of grazing,the size and taxonomic characteristics of phytoplankton are shifted towards a less edible community.The detrimental effect of elevated salinity on grazing rate supports growing concern about freshwater salinization negatively affecting water quality,particularly reducing top-down grazing control of phytoplankton.
文摘Fodder production in arid rangelands has been traditionally considered as the main source of nutrition for livestock.However,the production of these fodder may be influenced by some socio-economic and climatic factors.This study aims to identify the various rangeland use forms and determine the types of livestock feeding system in the El Ouara rangelands of Ben guarden District in southern Tunisia by analysing the importance of supplemental feeding and main determinants of this practice.Data were collected by a survey that targeted a sample of 50 breeders in the El Ouara rangelands.Descriptive statistics and binary logistic regression were used to analyse the data.The results showed that there are two types of association practiced by breeders:“Cherka”association practiced by 10.00% of breeders and cash payment association practiced by 53.00% of breeders.Then,transhumance,sedentary,and semi-urban forms are the main ways in which breeders use the rangelands.There are four livestock feeding systems in the El Ouara rangelands being used to feed livestock:natural rangeland,rangeland-based,mixed,and concentrate-based feeding systems.Supplemental feeding has become fundamental for the livestock feeding system in the El Ouara rangelands.The breeders with the largest camel size still use the natural rangeland feeding system,while the breeders who have the largest herd size practice the mixed feeding system.The logistic regression results reveal that breeder age,cereal area,herd size,migrant remittance,second activity,and agricultural development group membership can significantly impact the supplemental feeding.In summary,this study can help policy-makers plan innovative practices based on climatic change,ensure the sustainability of livestock feeding system,and make effective decisions for local development.