The newly identified aquaporin coding sequences presented here pave the way for further insights into the plant–water relations in the commercial strawberry(Fragaria x ananassa).Aquaporins are water channel proteins ...The newly identified aquaporin coding sequences presented here pave the way for further insights into the plant–water relations in the commercial strawberry(Fragaria x ananassa).Aquaporins are water channel proteins that allow water to cross(intra)cellular membranes.In Fragaria x ananassa,few of them have been identified hitherto,hampering the exploration of the water transport regulation at cellular level.Here,we present new aquaporin coding sequences belonging to different subclasses:plasma membrane intrinsic proteins subtype 1 and subtype 2(PIP1 and PIP2)and tonoplast intrinsic proteins(TIP).The classification is based on phylogenetic analysis and is confirmed by the presence of conserved residues.Substrate-specific signature sequences(SSSSs)and specificity-determining positions(SDPs)predict the substrate specificity of each new aquaporin.Expression profiling in leaves,petioles and developing fruits reveals distinct patterns,even within the same(sub)class.Expression profiles range from leaf-specific expression over constitutive expression to fruit-specific expression.Both upregulation and downregulation during fruit ripening occur.Substrate specificity and expression profiles suggest that functional specialization exists among aquaporins belonging to a different but also to the same(sub)class.展开更多
Background:Commercial pre-weaning diets are formulated to be highly digestible and nutrient-dense and contain low levels of dietary fibre.In contrast,pigs in a natural setting are manipulating fibre-rich plant materia...Background:Commercial pre-weaning diets are formulated to be highly digestible and nutrient-dense and contain low levels of dietary fibre.In contrast,pigs in a natural setting are manipulating fibre-rich plant material from a young age.Moreover,dietary fibre affects gastrointestinal tract(GIT)development and health in older pigs.We hypothesised that supplemental diets that contain vegetal fibres are accelerating GIT development in suckling piglets in terms of size and functionality.From d 2 of life,sow-suckled piglets had access to a low fibre diet(CON),a diet with a fermentable long-chain arabinoxylan(lc-AXOS),a diet with a largely non-fermentable purified cellulose(CELL),or a diet containing both fibres.During the initial 2 weeks,the control diet was a high-density milk replacer,followed by a dry and highly digestible creep meal.Upon weaning at 25 d,15 piglets from each treatment group,identified as eaters and originating from six or seven litters,were sacrificed for post-mortem examination of GIT morphology,small intestinal permeability and metabolic profile of the digesta.The microbiota composition of the mid-colon was evaluated in a sub-set of ten piglets.Results:No major statistical interactions between the fibre sources were observed.Piglets consumed the fibrecontaining milk supplements and creep diets well.Stomach size and small intestinal permeability was not affected.Large intestinal fill was increased with lc-AXOS only,while relative large intestinal weight was increased with both fibre sources(P<0.050).Also,CELL decreased ileal pH and tended to increase ileal DM content compared to CON(P<0.050).Moreover,the concentration of volatile fatty acids was increased in the caecum(P<0.100)and midcolon(P<0.050)by addition of CELL.lc-AXOS only stimulated caecal propionate(P<0.050).The microbiota composition showed a high individual variation and limited dietary impact.Nonetheless,CELL induced minor shifts in specific genera,with notable reductions of Escherichia-Shigella.Conclusions:Adding dietary fibres to the supplemental diet of suckling piglets altered large intestinal morphology but not small intestinal permeability.Moreover,dietary fibre showed effects on fermentation and modest changes of microbial populations in the hindgut,with more prominent effects from the low-fermentable cellulose.展开更多
The recent completion of the rose genome sequence is not the end of a process,but rather a starting point that opens up a whole set of new and exciting activities.Next to a high-quality genome sequence other genomic t...The recent completion of the rose genome sequence is not the end of a process,but rather a starting point that opens up a whole set of new and exciting activities.Next to a high-quality genome sequence other genomic tools have also become available for rose,including transcriptomics data,a high-density single-nucleotide polymorphism array and software to perform linkage and quantitative trait locus mapping in polyploids.Rose cultivars are highly heterogeneous and diverse.This vast diversity in cultivated roses can be explained through the genetic potential of the genus,introgressions from wild species into commercial tetraploid germplasm and the inimitable efforts of historical breeders.We can now investigate how this diversity can best be exploited and refined in future breeding work,given the rich molecular toolbox now available to the rose breeding community.This paper presents possible lines of research now that rose has entered the genomics era,and attempts to partially answer the question that arises after the completion of any draft genome sequence:‘Now that we have“the”genome,what’s next?’.Having access to a genome sequence will allow both(fundamental)scientific and(applied)breeding-orientated questions to be addressed.We outline possible approaches for a number of these questions.展开更多
To create asymmetric somatic hybrids, the genome of the so-called donor protoplast is fragmented prior to protoplast fusion. As a result, only a limited amount of the donor genome is transferred to the fusion product....To create asymmetric somatic hybrids, the genome of the so-called donor protoplast is fragmented prior to protoplast fusion. As a result, only a limited amount of the donor genome is transferred to the fusion product. This technique can circumvent some commonly observed problems related to symmetric fusion and offers a practical breeding tool for asexual hybridization. Genomes are typically fragmented by irradiation, microprotoplast production or application of metabolic inhibitors such as iodoacetamide. Irradiation and microprotoplast production fragment the nuclear genome, whereas iodoacetamide inactivates the cytoplasmic genome. It can therefore be used to introduce cytoplasmic male sterility, an important practical application. For hybrid verification and genome characterization, molecular markers and cytogenetic techniques are applied. This review highlights and discusses progress made during the last decade in spermatophytes asymmetric protoplast fusion.展开更多
In this work,the thermal sterilization process in food cans has been analyzed using Computational Fluid Dynamics(CFD).STAR CCM+software has been used in order to develop a numerical model to study the heating process ...In this work,the thermal sterilization process in food cans has been analyzed using Computational Fluid Dynamics(CFD).STAR CCM+software has been used in order to develop a numerical model to study the heating process of standard and the recently proposed toroidal shaped cans.The model has been validated comparing the results with the ones obtained experimentally and numerically that can be found in the literature.A good agreement between the obtained numerical results and the experimental ones has been obtained.The results also agree with other numerical models previously developed in the literature.Once the model has been validated,taking advance of the possibility to easily introduce movement in the simulations,new variables have been analyzed in the system using this model,such as rotational movement of the can.The model developed has been used to study the efficiency of the sterilization process with the two types of cans by means of calculating the temperature inside the systems and calculating the F0 parameter.It can be seen that the efficiency of the sterilization process is better in the toroidal cans.It has been also checked that CFD models can be very helpful in analyzing the temperature profiles inside the cans and making sure that the correct temperature has been obtained inside the can and the sterilization process has been correctly carried out.展开更多
Ergot alkaloids are mycotoxins which can be found in food based on cereal-crops, due to a contamination of plants by fungi of the genus Claviceps. The ingestion of ergot contaminated cereal crops can lead to a severe ...Ergot alkaloids are mycotoxins which can be found in food based on cereal-crops, due to a contamination of plants by fungi of the genus Claviceps. The ingestion of ergot contaminated cereal crops can lead to a severe poisoning known as ergotism. For food and feed safety purposes, the extraction of ergot alkaloids from ergot contaminated flour was investigated. For the specific recognition of ergot alkaloids, DNA aptamer ligands specially selected for ergot alkaloids were grafted onto silica gel in order to construct a specific solid phase extraction system. The aptamer-functionalized silica gels were used to extract ergot alkaloids from a contaminated rye feed sample. The presence of ergot alkaloids eluted from the aptamer-functionalized silica gels was analyzed using LC-QTOF-MS. By using this simple system, it was possible to specifically extract ergosine, ergokryptine and ergocornine from an ergot contaminated rye feed sample. This aptamer-based extraction tool shows the applicability of aptamers for the specific extraction of toxins or natural compounds from turbid matrices in a one-step procedure.展开更多
Current study evaluated the effect of a fine and coarsely ground insoluble dietary fibre source on the gastrointestinal development of suckling pigs.Oat hulls(OH)were selected as a model feedstuff,rich in cellulose,li...Current study evaluated the effect of a fine and coarsely ground insoluble dietary fibre source on the gastrointestinal development of suckling pigs.Oat hulls(OH)were selected as a model feedstuff,rich in cellulose,lignin,and insoluble dietary fibre.Three experimental supplemental diets were formulated:a finely ground,low fibre and nutrient dense diet served as control(CON).For the 2 high fibre diets,15%heat-treated starch in CON was exchanged with OH,either finely(OH-f)or coarsely ground(OH-c).Litters of 10 primi-and multiparous sows(mean litter size 14.6±0.84)were used.Within a litter,experimental diets were allotted to triplets of 4 piglets.From approximately 12 d of age,piglets’individual feed intakes were recorded 2 times per day when separated from their dam for 70 min.Piglets could suckle with their dam for the remainder of the day.On d 24 and 25,from the total pool of 120 piglets,seven healthy well-eating piglets per treatment were selected for post-mortem evaluation,resulting in 14 replicates per treatment.Consumption of OH-c and OH-f did not impede clinical health and production performance of piglets.The full stomach weights tended to be greater for OH-c compared to OH-f whereas CON was intermediate(P=0.083).Supplementing OH significantly increased ileal villus height and caecal dry matter concentration(P<0.05).For the colon,OH increased its length,contents weight,short-chain fatty acid concentration and reduced total bacterial count as well asγ-proteobacteria count and proportion(P<0.05).The OH-c treatment specifically increased full gastrointestinal tract weight and caecum contents weight compared to piglets fed CON and OH-f.Furthermore,OH-c reduced colonic crypt depth when compared to OH-f(P=0.018).In conclusion,supplementing OH to a diet for suckling piglets exerted subtle developmental effects on gastrointestinal morphology and colonic microbial community.These effects were largely independent from the particle size of the OH.展开更多
Greenhouse Building Energy Simulation(BES)models were developed to estimate the energy load using TRNSYS(ver.16,University of Wisconsin,USA),a commercial BES program.Validation was conducted based on data recorded dur...Greenhouse Building Energy Simulation(BES)models were developed to estimate the energy load using TRNSYS(ver.16,University of Wisconsin,USA),a commercial BES program.Validation was conducted based on data recorded during field experiments.The BES greenhouse modeling is reliable,as validation showed 5.2%and 5.5%compared with two field experiments,respectively.As the next step,the heating characteristics of the greenhouses were analyzed to predict the maximum and annual total heating loads based on the greenhouse types and target locations in the Republic of Korea using the validated greenhouse model.The BES-computed results indicated that the annual heating load was greatly affected by the local climate conditions of the target region.The annual heating load of greenhouses located in Chuncheon,the northernmost region,was 44.6%higher than greenhouses in Jeju,the southernmost area among the studied regions.The regression models for prediction of maximum heating load of Venlo type greenhouse and widespan type greenhouse were developed based on the BES computed results to easily predict maximum heating load at field and they explained nearly 95%and 80%of the variance in the data set used,respectively,with the predictor variables.Then a BES model of geothermal energy system was additionally designed and incorporated into the BES greenhouse model.The feasibility of the geothermal energy system for greenhouse was estimated through economic analysis.展开更多
Nitrogen(N)excreted by poultry is converted to ammonia(NH3),presenting an environmental risk and a health risk to the farmer and animals.A study was performed to investigate the effect of reduced CP and feed form on b...Nitrogen(N)excreted by poultry is converted to ammonia(NH3),presenting an environmental risk and a health risk to the farmer and animals.A study was performed to investigate the effect of reduced CP and feed form on broiler performance and welfare,meat and litter quality,N utilization,and NH3 concentrations at litter level.A total of 2,232 Ross 308 male broilers was divided into 6 treatments and 6 replicates,which was fed diets in both pellet and mash forms with different CP levels of 205.0 g/kg(H,high),187.5 g/kg(M,intermediate)and 175.0 g/kg(L,low)in the grower phase and 195.0 g/kg(H),180.0 g/kg(M)and 165.6 g/kg(L)in the finisher phase.Individual amino acids(AA)were supplemented to maintain digestible AA-to-digestible lysine ratios.Decreasing dietary CP content to 187.5 g/kg in the grower phase and 180.0 g/kg in the finisher phase reduced NH3 concentrations at litter level(P<0.001),but a further reduction in dietary CP had no additional effect.Mash treatments had better litter qualities and lower incidences of foot and hock lesions than pellet treatments at d 38(P<0.001).In addition,treatments with reduced CP had lower incidence of foot lesions at d 38(P<0.001).Broilers fed pelleted diets had higher ADFI,ADG,and final BW,improved feed conversion ratio(FCR),and heavier carcasses(P<0.001)than those fed mash diets over a production period of 39 d.Performance could not be maintained when birds were fed L CP pelleted diets.This study demonstrated that,with the supplementation of AA to meet requirements,the concentration of dietary CP can be reduced to 187.5 and 180.0 g/kg in the grower and finisher phases respectively,without impairing broiler performance,meat yield and quality.Mash diets were favorable when considering the overall litter quality and welfare of the birds.However,they could not maintain the same broiler performance and slaughter yield as pelleted diets.Results from the present study may assist the poultry sector towards a socially acceptable lowemission farming system.展开更多
We compared a 3-and 5-phase feeding program in terms of ammonia concentrations measured at litter level,litter composition and quality,nitrogen(N)utilization,performance,welfare,and meat deposition in broilers.A total...We compared a 3-and 5-phase feeding program in terms of ammonia concentrations measured at litter level,litter composition and quality,nitrogen(N)utilization,performance,welfare,and meat deposition in broilers.A total of 744 Ross 308 male broilers was divided into 2 treatments,each with 6 replicates.The 3-phase diets were formulated to CP and digestible lysine contents of 205 and 11.5 g/kg(0 to 9 d),195 and 10.8 g/kg(9 to 24 d),and 183.3 and 10.15 g/kg(24 to 39 d),respectively.The 5-phase diets had additional phases from 17 to 24 d and 32 to 39 d with CP and digestible lysine contents of 188 and 10.4 g/kg and 177 and 9.8 g/kg,respectively.Feeding 5 phases reduced the NH3concentrations at litter level by37.95%and 20.81%at 23(P<0.05)and 37 d of age(P<0.05),respectively.There was a tendency for a lower litter total ammoniacal nitrogen concentration for the 5-phase treatment than the 3-phase treatment at 24 and 39 d of age(P<0.1 for both).Total N concentration of the litter also tended to be lower for the 5-phase treatment at 39 d of age(P<0.1).The lower NH3coincided with a lower average litter pH at 24 and 32 d of age(P<0.05 for both).Birds fed the 5-phase treatments had a lower incidence of foot lesions at 24 d of age(P<0.001).Performance as well as carcass yield could be maintained,except for FCR,which was higher for the 5-phase treatment between 17 and 24 d of age and the overall period(P<0.05 and<0.001,respectively).The impact of the 5-phase treatment regarding the utilization of N(digestibility,excretion,and retention)was less clear,however the NH3volatilized from the litter was significantly reduced.Feeding 5 phases may therefore potentially reduce the NH3emitted from broiler houses which has several environmental and health benefits.Although the 5-phase treatment resulted in a significant decrease in feed efficiency,growth performance and meat deposition were maintained.展开更多
文摘The newly identified aquaporin coding sequences presented here pave the way for further insights into the plant–water relations in the commercial strawberry(Fragaria x ananassa).Aquaporins are water channel proteins that allow water to cross(intra)cellular membranes.In Fragaria x ananassa,few of them have been identified hitherto,hampering the exploration of the water transport regulation at cellular level.Here,we present new aquaporin coding sequences belonging to different subclasses:plasma membrane intrinsic proteins subtype 1 and subtype 2(PIP1 and PIP2)and tonoplast intrinsic proteins(TIP).The classification is based on phylogenetic analysis and is confirmed by the presence of conserved residues.Substrate-specific signature sequences(SSSSs)and specificity-determining positions(SDPs)predict the substrate specificity of each new aquaporin.Expression profiling in leaves,petioles and developing fruits reveals distinct patterns,even within the same(sub)class.Expression profiles range from leaf-specific expression over constitutive expression to fruit-specific expression.Both upregulation and downregulation during fruit ripening occur.Substrate specificity and expression profiles suggest that functional specialization exists among aquaporins belonging to a different but also to the same(sub)class.
文摘Background:Commercial pre-weaning diets are formulated to be highly digestible and nutrient-dense and contain low levels of dietary fibre.In contrast,pigs in a natural setting are manipulating fibre-rich plant material from a young age.Moreover,dietary fibre affects gastrointestinal tract(GIT)development and health in older pigs.We hypothesised that supplemental diets that contain vegetal fibres are accelerating GIT development in suckling piglets in terms of size and functionality.From d 2 of life,sow-suckled piglets had access to a low fibre diet(CON),a diet with a fermentable long-chain arabinoxylan(lc-AXOS),a diet with a largely non-fermentable purified cellulose(CELL),or a diet containing both fibres.During the initial 2 weeks,the control diet was a high-density milk replacer,followed by a dry and highly digestible creep meal.Upon weaning at 25 d,15 piglets from each treatment group,identified as eaters and originating from six or seven litters,were sacrificed for post-mortem examination of GIT morphology,small intestinal permeability and metabolic profile of the digesta.The microbiota composition of the mid-colon was evaluated in a sub-set of ten piglets.Results:No major statistical interactions between the fibre sources were observed.Piglets consumed the fibrecontaining milk supplements and creep diets well.Stomach size and small intestinal permeability was not affected.Large intestinal fill was increased with lc-AXOS only,while relative large intestinal weight was increased with both fibre sources(P<0.050).Also,CELL decreased ileal pH and tended to increase ileal DM content compared to CON(P<0.050).Moreover,the concentration of volatile fatty acids was increased in the caecum(P<0.100)and midcolon(P<0.050)by addition of CELL.lc-AXOS only stimulated caecal propionate(P<0.050).The microbiota composition showed a high individual variation and limited dietary impact.Nonetheless,CELL induced minor shifts in specific genera,with notable reductions of Escherichia-Shigella.Conclusions:Adding dietary fibres to the supplemental diet of suckling piglets altered large intestinal morphology but not small intestinal permeability.Moreover,dietary fibre showed effects on fermentation and modest changes of microbial populations in the hindgut,with more prominent effects from the low-fermentable cellulose.
基金supported in part by the TKI polyploids project‘Novel genetic and genomic tools for polyploid crops’(BO-26.03-009-004 and BO-50-002-022).
文摘The recent completion of the rose genome sequence is not the end of a process,but rather a starting point that opens up a whole set of new and exciting activities.Next to a high-quality genome sequence other genomic tools have also become available for rose,including transcriptomics data,a high-density single-nucleotide polymorphism array and software to perform linkage and quantitative trait locus mapping in polyploids.Rose cultivars are highly heterogeneous and diverse.This vast diversity in cultivated roses can be explained through the genetic potential of the genus,introgressions from wild species into commercial tetraploid germplasm and the inimitable efforts of historical breeders.We can now investigate how this diversity can best be exploited and refined in future breeding work,given the rich molecular toolbox now available to the rose breeding community.This paper presents possible lines of research now that rose has entered the genomics era,and attempts to partially answer the question that arises after the completion of any draft genome sequence:‘Now that we have“the”genome,what’s next?’.Having access to a genome sequence will allow both(fundamental)scientific and(applied)breeding-orientated questions to be addressed.We outline possible approaches for a number of these questions.
文摘To create asymmetric somatic hybrids, the genome of the so-called donor protoplast is fragmented prior to protoplast fusion. As a result, only a limited amount of the donor genome is transferred to the fusion product. This technique can circumvent some commonly observed problems related to symmetric fusion and offers a practical breeding tool for asexual hybridization. Genomes are typically fragmented by irradiation, microprotoplast production or application of metabolic inhibitors such as iodoacetamide. Irradiation and microprotoplast production fragment the nuclear genome, whereas iodoacetamide inactivates the cytoplasmic genome. It can therefore be used to introduce cytoplasmic male sterility, an important practical application. For hybrid verification and genome characterization, molecular markers and cytogenetic techniques are applied. This review highlights and discusses progress made during the last decade in spermatophytes asymmetric protoplast fusion.
基金This work was carried out in the framework of the SUSFOOD2 funded InProVe Project and the Project“Procesamiento Innovador de Verduras y Patatas”(PCI2018-093129)of the Spanish GovernmentIt was also supported by the Research Group Program(IT1505-22)μ4F(KK-2021/00082)from the Basque Government.
文摘In this work,the thermal sterilization process in food cans has been analyzed using Computational Fluid Dynamics(CFD).STAR CCM+software has been used in order to develop a numerical model to study the heating process of standard and the recently proposed toroidal shaped cans.The model has been validated comparing the results with the ones obtained experimentally and numerically that can be found in the literature.A good agreement between the obtained numerical results and the experimental ones has been obtained.The results also agree with other numerical models previously developed in the literature.Once the model has been validated,taking advance of the possibility to easily introduce movement in the simulations,new variables have been analyzed in the system using this model,such as rotational movement of the can.The model developed has been used to study the efficiency of the sterilization process with the two types of cans by means of calculating the temperature inside the systems and calculating the F0 parameter.It can be seen that the efficiency of the sterilization process is better in the toroidal cans.It has been also checked that CFD models can be very helpful in analyzing the temperature profiles inside the cans and making sure that the correct temperature has been obtained inside the can and the sterilization process has been correctly carried out.
文摘Ergot alkaloids are mycotoxins which can be found in food based on cereal-crops, due to a contamination of plants by fungi of the genus Claviceps. The ingestion of ergot contaminated cereal crops can lead to a severe poisoning known as ergotism. For food and feed safety purposes, the extraction of ergot alkaloids from ergot contaminated flour was investigated. For the specific recognition of ergot alkaloids, DNA aptamer ligands specially selected for ergot alkaloids were grafted onto silica gel in order to construct a specific solid phase extraction system. The aptamer-functionalized silica gels were used to extract ergot alkaloids from a contaminated rye feed sample. The presence of ergot alkaloids eluted from the aptamer-functionalized silica gels was analyzed using LC-QTOF-MS. By using this simple system, it was possible to specifically extract ergosine, ergokryptine and ergocornine from an ergot contaminated rye feed sample. This aptamer-based extraction tool shows the applicability of aptamers for the specific extraction of toxins or natural compounds from turbid matrices in a one-step procedure.
文摘Current study evaluated the effect of a fine and coarsely ground insoluble dietary fibre source on the gastrointestinal development of suckling pigs.Oat hulls(OH)were selected as a model feedstuff,rich in cellulose,lignin,and insoluble dietary fibre.Three experimental supplemental diets were formulated:a finely ground,low fibre and nutrient dense diet served as control(CON).For the 2 high fibre diets,15%heat-treated starch in CON was exchanged with OH,either finely(OH-f)or coarsely ground(OH-c).Litters of 10 primi-and multiparous sows(mean litter size 14.6±0.84)were used.Within a litter,experimental diets were allotted to triplets of 4 piglets.From approximately 12 d of age,piglets’individual feed intakes were recorded 2 times per day when separated from their dam for 70 min.Piglets could suckle with their dam for the remainder of the day.On d 24 and 25,from the total pool of 120 piglets,seven healthy well-eating piglets per treatment were selected for post-mortem evaluation,resulting in 14 replicates per treatment.Consumption of OH-c and OH-f did not impede clinical health and production performance of piglets.The full stomach weights tended to be greater for OH-c compared to OH-f whereas CON was intermediate(P=0.083).Supplementing OH significantly increased ileal villus height and caecal dry matter concentration(P<0.05).For the colon,OH increased its length,contents weight,short-chain fatty acid concentration and reduced total bacterial count as well asγ-proteobacteria count and proportion(P<0.05).The OH-c treatment specifically increased full gastrointestinal tract weight and caecum contents weight compared to piglets fed CON and OH-f.Furthermore,OH-c reduced colonic crypt depth when compared to OH-f(P=0.018).In conclusion,supplementing OH to a diet for suckling piglets exerted subtle developmental effects on gastrointestinal morphology and colonic microbial community.These effects were largely independent from the particle size of the OH.
基金This work was carried out with the support of the“Cooperative Research Program for Agriculture Science&Technology Development(Project No.PJ009412)”Rural Development Administration,Republic of Korea.
文摘Greenhouse Building Energy Simulation(BES)models were developed to estimate the energy load using TRNSYS(ver.16,University of Wisconsin,USA),a commercial BES program.Validation was conducted based on data recorded during field experiments.The BES greenhouse modeling is reliable,as validation showed 5.2%and 5.5%compared with two field experiments,respectively.As the next step,the heating characteristics of the greenhouses were analyzed to predict the maximum and annual total heating loads based on the greenhouse types and target locations in the Republic of Korea using the validated greenhouse model.The BES-computed results indicated that the annual heating load was greatly affected by the local climate conditions of the target region.The annual heating load of greenhouses located in Chuncheon,the northernmost region,was 44.6%higher than greenhouses in Jeju,the southernmost area among the studied regions.The regression models for prediction of maximum heating load of Venlo type greenhouse and widespan type greenhouse were developed based on the BES computed results to easily predict maximum heating load at field and they explained nearly 95%and 80%of the variance in the data set used,respectively,with the predictor variables.Then a BES model of geothermal energy system was additionally designed and incorporated into the BES greenhouse model.The feasibility of the geothermal energy system for greenhouse was estimated through economic analysis.
基金This study wasfinancially supported by Flanders Innovation and Entrepreneurship(VLAIO)(project number 160778)and ILVO.
文摘Nitrogen(N)excreted by poultry is converted to ammonia(NH3),presenting an environmental risk and a health risk to the farmer and animals.A study was performed to investigate the effect of reduced CP and feed form on broiler performance and welfare,meat and litter quality,N utilization,and NH3 concentrations at litter level.A total of 2,232 Ross 308 male broilers was divided into 6 treatments and 6 replicates,which was fed diets in both pellet and mash forms with different CP levels of 205.0 g/kg(H,high),187.5 g/kg(M,intermediate)and 175.0 g/kg(L,low)in the grower phase and 195.0 g/kg(H),180.0 g/kg(M)and 165.6 g/kg(L)in the finisher phase.Individual amino acids(AA)were supplemented to maintain digestible AA-to-digestible lysine ratios.Decreasing dietary CP content to 187.5 g/kg in the grower phase and 180.0 g/kg in the finisher phase reduced NH3 concentrations at litter level(P<0.001),but a further reduction in dietary CP had no additional effect.Mash treatments had better litter qualities and lower incidences of foot and hock lesions than pellet treatments at d 38(P<0.001).In addition,treatments with reduced CP had lower incidence of foot lesions at d 38(P<0.001).Broilers fed pelleted diets had higher ADFI,ADG,and final BW,improved feed conversion ratio(FCR),and heavier carcasses(P<0.001)than those fed mash diets over a production period of 39 d.Performance could not be maintained when birds were fed L CP pelleted diets.This study demonstrated that,with the supplementation of AA to meet requirements,the concentration of dietary CP can be reduced to 187.5 and 180.0 g/kg in the grower and finisher phases respectively,without impairing broiler performance,meat yield and quality.Mash diets were favorable when considering the overall litter quality and welfare of the birds.However,they could not maintain the same broiler performance and slaughter yield as pelleted diets.Results from the present study may assist the poultry sector towards a socially acceptable lowemission farming system.
基金Flanders Innovation and Entrepreneurship(VLAIO)(project number 160778)and ILVO。
文摘We compared a 3-and 5-phase feeding program in terms of ammonia concentrations measured at litter level,litter composition and quality,nitrogen(N)utilization,performance,welfare,and meat deposition in broilers.A total of 744 Ross 308 male broilers was divided into 2 treatments,each with 6 replicates.The 3-phase diets were formulated to CP and digestible lysine contents of 205 and 11.5 g/kg(0 to 9 d),195 and 10.8 g/kg(9 to 24 d),and 183.3 and 10.15 g/kg(24 to 39 d),respectively.The 5-phase diets had additional phases from 17 to 24 d and 32 to 39 d with CP and digestible lysine contents of 188 and 10.4 g/kg and 177 and 9.8 g/kg,respectively.Feeding 5 phases reduced the NH3concentrations at litter level by37.95%and 20.81%at 23(P<0.05)and 37 d of age(P<0.05),respectively.There was a tendency for a lower litter total ammoniacal nitrogen concentration for the 5-phase treatment than the 3-phase treatment at 24 and 39 d of age(P<0.1 for both).Total N concentration of the litter also tended to be lower for the 5-phase treatment at 39 d of age(P<0.1).The lower NH3coincided with a lower average litter pH at 24 and 32 d of age(P<0.05 for both).Birds fed the 5-phase treatments had a lower incidence of foot lesions at 24 d of age(P<0.001).Performance as well as carcass yield could be maintained,except for FCR,which was higher for the 5-phase treatment between 17 and 24 d of age and the overall period(P<0.05 and<0.001,respectively).The impact of the 5-phase treatment regarding the utilization of N(digestibility,excretion,and retention)was less clear,however the NH3volatilized from the litter was significantly reduced.Feeding 5 phases may therefore potentially reduce the NH3emitted from broiler houses which has several environmental and health benefits.Although the 5-phase treatment resulted in a significant decrease in feed efficiency,growth performance and meat deposition were maintained.
