Interest in mung bean(Vigna radiata L.) as a functional food is growing; however, studies on the nutritional composition of major mung bean cultivars planted in China are limited.Twenty Chinese mung bean cultivars wer...Interest in mung bean(Vigna radiata L.) as a functional food is growing; however, studies on the nutritional composition of major mung bean cultivars planted in China are limited.Twenty Chinese mung bean cultivars were collected and their nutritional compositions including starch, fat, protein, and phytochemicals were analyzed. The cultivars were found to have a high amount of resistant starch, accounting for 16.1%–22.3% of total starch, and balanced amino acid constitutions. Palmitic acid and linoleic acid were the two dominant fatty acids, accounting for respectively 32.4% and 36.1% of all of the assayed fatty acids. Four bound phenolic acids(syringic, caffeic, p-coumaric, and ferulic acids) and two free phenolic acids(caffeic and ferulic acids) were identified by HPLC. The antioxidant activity of 70%ethanol extracts from the 20 mung bean cultivars was evaluated. Their DPPH and ABTS+free-radical-scavenging capacity ranged from 28.13 ± 2.24 to 35.68 ± 0.71 μmol g-1and from3.82 ± 0.25 to 13.44 ± 1.76 μmol g-1, respectively. Significant positive correlations of ABTS+free-radical-scavenging capacity with total phenolic acids and total flavonoid contents were observed. These results suggest that Chinese mung bean cultivars are rich in balanced nutrients and that their phytochemicals should be considered as potential sources of natural antioxidants.展开更多
The partial 16 S r RNA gene sequences（100 to 500 bp） were widely used to reveal rumen bacterial composition influenced by diets, while quantification of the changed uncultured bacteria was inconvenient due to diffic...The partial 16 S r RNA gene sequences（100 to 500 bp） were widely used to reveal rumen bacterial composition influenced by diets, while quantification of the changed uncultured bacteria was inconvenient due to difficult designing of specific primers based on short sequences. This study evaluated the effect of forage resources on rumen bacterial diversity and developed new strategy for primer design based on short sequences to quantify the changed uncultured bacteria. Denaturing gradient gel electrophoresis（DGGE） analysis and subsequent band sequencing were used to reveal the distinct rumen bacteria composition in cows fed with two forage sources（single corn stover vs. mixed forages including alfalfa hay and corn silage）. The bacterial diversity in the rumen of dairy cows fed with corn stover was lower than that with mixed forages（P0.05）. The bacterium named R-UB affiliating to uncultured Succinivibrionaceae was identified, and it was abundant in the rumen of cows fed with mixed forages compared to corn stover. The full length 16 S r RNA gene sequences with identity of 97% to the R-UB 16 S r RNA gene sequence were obtained from Gen Bank and used to design specific primers to quantify uncultured bacterium R-UB. All sequences of amplicon from the new primers were of 100% identity to R-UB sequences indicating the high specificity of new primers. Quantitative PCR confirmed that abundance of R-UB in the rumen of cows fed with corn stover was lower than those fed with mixed forages（P0.01）. New strategy for designing primers based on partial 16 S r RNA genes to quantify targeted uncultured bacteria was successfully developed. The rumen bacteria descending significantly in the cows fed corn stover compared to those fed mixed forages was identified as uncultured R-UB from Succinivibrionaceae.展开更多
Background:The transition period is a challenging period for high-producing dairy cattle.Cows in early lactation are considered as a group at risk of subacute ruminal acidosis(SARA).Variability in SARA susceptibility ...Background:The transition period is a challenging period for high-producing dairy cattle.Cows in early lactation are considered as a group at risk of subacute ruminal acidosis(SARA).Variability in SARA susceptibility in early lactation is hypothesized to be reflected in fecal characteristics such as fecal pH,dry matter content,volatile and odd-and branched-chain fatty acids(VFA and OBCFA,respectively),as well as fecal microbiota.This was investigated with 38 periparturient dairy cows,which were classified into four groups differing in median and mean time of reticular pH below 6 as well as area under the curve of pH below 6.Furthermore,we investigated whether fecal differences were already obvious during a period prior to the SARA risk(prepartum).Results:Variation in reticular pH during a 3-week postpartum period was not associated with differences in fecal pH and VFA concentration.In the postpartum period,the copy number of fecal bacteria and methanogens of unsusceptible(UN)cows was higher than moderately susceptible(MS)or susceptible(SU)cows,while the genera Ruminococcus and Prevotellacea_UCG-001 were proportionally less abundant in UN compared with SU cows.Nevertheless,only a minor reduction was observed in iso-BCFA proportions in fecal fatty acids of SU cows,particularly iso-C15:0and iso-C16:0,compared with UN cows.Consistent with the bacterial changes postpartum,the lower abundance of Ruminococcus was already observed in the prepartum fecal bacterial communities of UN cows,whereas Lachnospiraceae_UCG-001 was increased.Nevertheless,no differences were observed in the prepartum fecal VFA or OBCFA profiles among the groups.Prepartum fecal bacterial communities of cows were clustered into two distinct clusters with 70%of the SU cows belonging to cluster 1,in which they represented 60%of the animals.Conclusions:Inter-animal variation in postpartum SARA susceptibility was reflected in post-and prepartum fecal bacterial communities.Differences in prepartum fecal bacterial communities could alert for susceptibility to develop SARA postpartum.Our results generated knowledge on the association between fecal bacteria and SARA development which could be further explored in a prevention strategy.展开更多
Accurate assessment of feed's Carbohydrate( CHO) and protein nutritional values and rumen metabolism are significant for dairy production. Cornell Net Carbohydrate and Protein System( CNCPS) as an important method...Accurate assessment of feed's Carbohydrate( CHO) and protein nutritional values and rumen metabolism are significant for dairy production. Cornell Net Carbohydrate and Protein System( CNCPS) as an important method to evaluate feedstuff nutritional values,hasn't been widely used in China. In order to illustrate updates of CNCPS systems deeply,the following sections were reviewed:( i) CHO and protein fractions were updated,CA was subdivided into CA1,CA2,CA3 and CA4 in CNCPS v6. 1,protein was reclassified into PA1,PA2,PB1,PB2 and PC after CNCPS v6. 1. Content of CHO and protein fractions vary in different feedstuff and affected by feed processing;( ii) Degradation rates( Kd) values for the new CA expanded scheme were updated to 0,7,5,40- 60 % h^(-1)respectively,Kd for PA and PB1 decreased to 200 % h^(-1)and 10- 40 % h^(-1);( iii) Equations for passage rate( Kp) initially includes Kpf( Kp of forages) and Kpc( Kp of concentrates),and adjusted by effective NDF( e NDF),while in CNCPS v5. 0,Kpl( Kp of liquids) equation was added and e NDF was replaced by physically effective NDF( pe NDF). In CNCPS v6. 1,Fp BW and Cp BW were integrated into Kp equations and pe NDF was abandoned.( iv)The relationship and difference among Weende system of proximate analysis,Van Soest fiber analysis~[35],NRC( 2001)~[28]and CNCPS were analyzed. The first two systems laid the foundation for NRC( 2001) and CNCPS system. The latter two systems are different in CHO and protein division,also NRC( 2001) developed separate Kp equations for wet and dry forages but no equation for Kpl. CNCPS developed a Kp equation that work for wet and dry forages,and Kpl equation was established. In conclusion,the division and development of CHO and protein fractions,the update of Kd and Kp equation were reviewed systematically.展开更多
Possible ways to reduce antibiotic use in rabbit production are discussed, based on a literature survey. Several management strategies have been proven to successfully reduce disease pressure in rabbit production. The...Possible ways to reduce antibiotic use in rabbit production are discussed, based on a literature survey. Several management strategies have been proven to successfully reduce disease pressure in rabbit production. The primary way of reducing risk of disease is ＂all-in all-out＂ management, as it allows thorough cleaning and disinfection. A second tool is choosing reproduction stock with a minimal disease level. Animals with a near Specific-Pathogen-Free （SPF） status, or even entirely disease-free animals, lead to high-health-status farms where antibiotics are rarely used. To reduce the risk of enteritis, quantitative aspects in the early fattening stage are important, apart from some ,qualitative feed characteristics （especially the carbohydrate complex）. Finally, despite discussions about their effectiveness, pro/prebiotics and some other additives have shown some potential in reducing enteric problems. Alternatives to antibiotics are only useful, however, if the whole chain （reproduction stock producers, breeders, feed companies, slaughterhouses and even veterinarians） is convinced and forced into a globally consistent strategy. In the absence of such a consistent approach, both preventive and curative use of antibiotics remains the easiest and most inexpensive way to control disease in rabbit production.展开更多
Objective: To evaluate the expression of DNA plasmid-harboring modified antibody gene that produces neutralizing human monoclonal antibodies against four serotypes of dengue virus(DENV) without enhancing activity in B...Objective: To evaluate the expression of DNA plasmid-harboring modified antibody gene that produces neutralizing human monoclonal antibodies against four serotypes of dengue virus(DENV) without enhancing activity in BALB/c mice. Methods: We constructed pFUSE-based vectors(pFUSE1 G7 C2hVH and pFUSE1 G7 C2hVL) containing genes encoding the variable domains of the heavy or light chain of the anti-dengue virus antibody 1 G7 C2, a human IgG1 that has been characterized for its neutralizing activity to DENV-1-4. Leucine(L) at positions 234 and 235 on the Fc CH2 domain in pFUSE1 G7 C2hVH was mutated to alanine(A)(LALA mutation) by site direct mutagenesis, and the new plasmid was termed pFUSE1 G7 C2hVHLALA. An equal amount of pFUSE1 G7 C2hVL and 1 G7 C2hG1-LALA plasmids were co-transfected into Chinese hamster ovary cells(CHO-K1) and a single dose of 100 μg 1 G7 C2hG1-LALA plasmid was intramuscularly injected, followed by electroporation in BALB/c mice. The secreted 1 G7 C2hG1-LALA antibodies in cell culture supernatant and mouse serum were examined for their biological functions, neutralization and enhancing activity. Results: The co-transfection of heavy-and light-chain 1 G7 C2hG1-LALA plasmids in CHO-K1 cells produced approximately 3 900 ng/mL human IgG and neutralized 90%-100% all four DENV, with no enhancing activity. Furthermore, the modified human IgG was produced more than 1 000 ng/mL in mouse serum on day 7 post plasmid injection and showed cross-neutralization to four DENV serotypes. Subsequently, antibody production and neutralization decreased rapidly. Nevertheless, the secreted neutralizing 1 G7 C2hG1-LALA in mouse serum demonstrated complete absence of enhancing activities to all DENV serotypes. Conclusions: These findings reveal that a new modified 1 G7 C2h G1-LALA expressing plasmid based on gene transfer is a possible therapeutic antibody candidate against DENV infection.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
In this study,we investigated the transcriptional spatio-temporal dynamics of the taste 1 receptor(T1R)gene family repertoire in seabream(Sparus aurata[sa]),during larval ontogeny and in adult tissues.In early larval ...In this study,we investigated the transcriptional spatio-temporal dynamics of the taste 1 receptor(T1R)gene family repertoire in seabream(Sparus aurata[sa]),during larval ontogeny and in adult tissues.In early larval development,sa T1R expression arises heterochronously,i.e.the extraoral taste-related perception in the gastrointestinal tract(GIT)anticipates first exogenous feeding(at 9 days post hatching[dph]),followed by the buccal/intraoral perception from 14 dph onwards,supporting the hypothesis that the early onset of the molecular machinery underlying sa T1R expression in the GIT is not induced by food but rather genetically hardwired.During adulthood,we characterized the expression patterns of sa T1R within specific tissues(n=4)distributed in oropharingeal,GIT and brain regions substantiating their functional versatility as chemosensory signaling players to a variety of biological functions beyond oral taste sensation.Further,we provided for the first time direct evidences in fish for m RNA coexpression of a subset of sa T1R genes(mostly sa T1R3,i.e.the common subunit of the heterodimeric T1R complexes for the detection of“sweet”and“umami”substances),with the selected gut peptides ghrelin(ghr),cholecystokinin(cck),hormone peptide yy(pyy)and proglucagon(pg).Each peptide defines the enteroendocrine cells(ECCs)identity,and establishes on morphological basis,a direct link for T1R chemosensing in the regulation of fish digestive processes.Finally,we analyzed the spatial gene expression patterns of 2 taste signaling components functionally homologous to the mammalian G(i)a subunit gustducin,namely sa G(i)a1 and sa G(i)a2,and demonstrated their co-localization with the sa T1R3in EECs,thus validating their direct involvement in taste-like transduction mechanisms of the fish GIT.In conclusion,data provide new insights in the evolutionary conservation of gut sensing in fish suggesting a conserved role for nutrient sensors modulating entero-endocrine secretion.展开更多
The present study investigated the potential effects of an umami taste stimulator(UTS)on largemouth bass(Micropterus salmoides)fed a high plant protein diet.Two isonitrogenous and isolipidic diets were formulated with...The present study investigated the potential effects of an umami taste stimulator(UTS)on largemouth bass(Micropterus salmoides)fed a high plant protein diet.Two isonitrogenous and isolipidic diets were formulated with 40%fishmeal(positive control,PC)and 25%fishmeal(negative control,NC),respectively.The other three diets were supplemented with 0.10%,0.15%and 0.20%of the UTS based on NC group.Five groups of fish(mean initial weight 29.82±0.04 g)were fed twice daily for 64 days.The results indicated that feed intake,growth performance,and taste receptor and enteroendocrine-related genes expression(pyya,t1r1 and ghrl)in NC group were significantly reduced compared with PC group,which were improved with dietary supplementation of the UTS(at 0.15%and 0.20%).In addition,muscle thickness of midgut and hindgut,villus length of hindgut in the NC group were reduced compared to the PC group,but they improved with dietary UTS supplementation.Also,antioxidant capacity,and expression of genes involved in peptide and amino acid transport and target of rapamycin(TOR)pathway were reduced in the NC group compared to the PC group.However,the inclusion of UTS improved the total antioxidant capacity,superoxide dismutase and catalase compared with the NC group.Peptide and amino acid transporters(lat1,lat2,snat2 and pept2)and TOR pathway(tor,akt1,4ebp1 and s6)related genes’expression were also ameliorated by UTS addition compared to the NC group.In summary,UTS supplementation could improve the appetite,growth performance,and health status of largemouth bass,and the recommended additional amount of UTS was 0.15%-0.20%.展开更多
基金supported by the earmarked fund for China Agriculture Research System (No. CYTX-014)the Agricultural Science and Technology Innovation Program of CAAS+1 种基金the Program of Science and Technology Cooperation with Hong Kong, Macao, and Taiwan, China (No. 2013DFH30050)the special fund for Agro-scientific Research in the Public Interest (No. 201403063)
文摘Interest in mung bean(Vigna radiata L.) as a functional food is growing; however, studies on the nutritional composition of major mung bean cultivars planted in China are limited.Twenty Chinese mung bean cultivars were collected and their nutritional compositions including starch, fat, protein, and phytochemicals were analyzed. The cultivars were found to have a high amount of resistant starch, accounting for 16.1%–22.3% of total starch, and balanced amino acid constitutions. Palmitic acid and linoleic acid were the two dominant fatty acids, accounting for respectively 32.4% and 36.1% of all of the assayed fatty acids. Four bound phenolic acids(syringic, caffeic, p-coumaric, and ferulic acids) and two free phenolic acids(caffeic and ferulic acids) were identified by HPLC. The antioxidant activity of 70%ethanol extracts from the 20 mung bean cultivars was evaluated. Their DPPH and ABTS+free-radical-scavenging capacity ranged from 28.13 ± 2.24 to 35.68 ± 0.71 μmol g-1and from3.82 ± 0.25 to 13.44 ± 1.76 μmol g-1, respectively. Significant positive correlations of ABTS+free-radical-scavenging capacity with total phenolic acids and total flavonoid contents were observed. These results suggest that Chinese mung bean cultivars are rich in balanced nutrients and that their phytochemicals should be considered as potential sources of natural antioxidants.
基金supported by the National Natural Science Foundation of China(31261140365)the National Basic Research Program of China(2011CB100804)the Agricultural Science and Technology Innovation Program of Chinese Academy of Agricultural Sciences(ASTIP-IAS12)
文摘The partial 16 S r RNA gene sequences（100 to 500 bp） were widely used to reveal rumen bacterial composition influenced by diets, while quantification of the changed uncultured bacteria was inconvenient due to difficult designing of specific primers based on short sequences. This study evaluated the effect of forage resources on rumen bacterial diversity and developed new strategy for primer design based on short sequences to quantify the changed uncultured bacteria. Denaturing gradient gel electrophoresis（DGGE） analysis and subsequent band sequencing were used to reveal the distinct rumen bacteria composition in cows fed with two forage sources（single corn stover vs. mixed forages including alfalfa hay and corn silage）. The bacterial diversity in the rumen of dairy cows fed with corn stover was lower than that with mixed forages（P0.05）. The bacterium named R-UB affiliating to uncultured Succinivibrionaceae was identified, and it was abundant in the rumen of cows fed with mixed forages compared to corn stover. The full length 16 S r RNA gene sequences with identity of 97% to the R-UB 16 S r RNA gene sequence were obtained from Gen Bank and used to design specific primers to quantify uncultured bacterium R-UB. All sequences of amplicon from the new primers were of 100% identity to R-UB sequences indicating the high specificity of new primers. Quantitative PCR confirmed that abundance of R-UB in the rumen of cows fed with corn stover was lower than those fed with mixed forages（P0.01）. New strategy for designing primers based on partial 16 S r RNA genes to quantify targeted uncultured bacteria was successfully developed. The rumen bacteria descending significantly in the cows fed corn stover compared to those fed mixed forages was identified as uncultured R-UB from Succinivibrionaceae.
基金the financial support of Flanders Innovation&Entrepreneurship(VLAIOBelgium+3 种基金LA170830)the European Union’s Horizon 2020 research and innovation programme under grant agreement 101000213-Holo RuminantThe PhD research of Hong Yang and Xiaoping Jing was the Chinese Scholarship Council(CSC,China)the PhD research of Stijn Heirbaut was funded by a Ph D grant from the Special Research Fund of the Ghent University(Bijzonder Onderzoeksfonds,BOF,Belgium)。
文摘Background:The transition period is a challenging period for high-producing dairy cattle.Cows in early lactation are considered as a group at risk of subacute ruminal acidosis(SARA).Variability in SARA susceptibility in early lactation is hypothesized to be reflected in fecal characteristics such as fecal pH,dry matter content,volatile and odd-and branched-chain fatty acids(VFA and OBCFA,respectively),as well as fecal microbiota.This was investigated with 38 periparturient dairy cows,which were classified into four groups differing in median and mean time of reticular pH below 6 as well as area under the curve of pH below 6.Furthermore,we investigated whether fecal differences were already obvious during a period prior to the SARA risk(prepartum).Results:Variation in reticular pH during a 3-week postpartum period was not associated with differences in fecal pH and VFA concentration.In the postpartum period,the copy number of fecal bacteria and methanogens of unsusceptible(UN)cows was higher than moderately susceptible(MS)or susceptible(SU)cows,while the genera Ruminococcus and Prevotellacea_UCG-001 were proportionally less abundant in UN compared with SU cows.Nevertheless,only a minor reduction was observed in iso-BCFA proportions in fecal fatty acids of SU cows,particularly iso-C15:0and iso-C16:0,compared with UN cows.Consistent with the bacterial changes postpartum,the lower abundance of Ruminococcus was already observed in the prepartum fecal bacterial communities of UN cows,whereas Lachnospiraceae_UCG-001 was increased.Nevertheless,no differences were observed in the prepartum fecal VFA or OBCFA profiles among the groups.Prepartum fecal bacterial communities of cows were clustered into two distinct clusters with 70%of the SU cows belonging to cluster 1,in which they represented 60%of the animals.Conclusions:Inter-animal variation in postpartum SARA susceptibility was reflected in post-and prepartum fecal bacterial communities.Differences in prepartum fecal bacterial communities could alert for susceptibility to develop SARA postpartum.Our results generated knowledge on the association between fecal bacteria and SARA development which could be further explored in a prevention strategy.
基金Supported by National Natural Science Foundation of China(31572435)Creative Workgroup on Dairy Industry of Beijing City 2012
文摘Accurate assessment of feed's Carbohydrate( CHO) and protein nutritional values and rumen metabolism are significant for dairy production. Cornell Net Carbohydrate and Protein System( CNCPS) as an important method to evaluate feedstuff nutritional values,hasn't been widely used in China. In order to illustrate updates of CNCPS systems deeply,the following sections were reviewed:( i) CHO and protein fractions were updated,CA was subdivided into CA1,CA2,CA3 and CA4 in CNCPS v6. 1,protein was reclassified into PA1,PA2,PB1,PB2 and PC after CNCPS v6. 1. Content of CHO and protein fractions vary in different feedstuff and affected by feed processing;( ii) Degradation rates( Kd) values for the new CA expanded scheme were updated to 0,7,5,40- 60 % h^(-1)respectively,Kd for PA and PB1 decreased to 200 % h^(-1)and 10- 40 % h^(-1);( iii) Equations for passage rate( Kp) initially includes Kpf( Kp of forages) and Kpc( Kp of concentrates),and adjusted by effective NDF( e NDF),while in CNCPS v5. 0,Kpl( Kp of liquids) equation was added and e NDF was replaced by physically effective NDF( pe NDF). In CNCPS v6. 1,Fp BW and Cp BW were integrated into Kp equations and pe NDF was abandoned.( iv)The relationship and difference among Weende system of proximate analysis,Van Soest fiber analysis~[35],NRC( 2001)~[28]and CNCPS were analyzed. The first two systems laid the foundation for NRC( 2001) and CNCPS system. The latter two systems are different in CHO and protein division,also NRC( 2001) developed separate Kp equations for wet and dry forages but no equation for Kpl. CNCPS developed a Kp equation that work for wet and dry forages,and Kpl equation was established. In conclusion,the division and development of CHO and protein fractions,the update of Kd and Kp equation were reviewed systematically.
文摘Possible ways to reduce antibiotic use in rabbit production are discussed, based on a literature survey. Several management strategies have been proven to successfully reduce disease pressure in rabbit production. The primary way of reducing risk of disease is ＂all-in all-out＂ management, as it allows thorough cleaning and disinfection. A second tool is choosing reproduction stock with a minimal disease level. Animals with a near Specific-Pathogen-Free （SPF） status, or even entirely disease-free animals, lead to high-health-status farms where antibiotics are rarely used. To reduce the risk of enteritis, quantitative aspects in the early fattening stage are important, apart from some ,qualitative feed characteristics （especially the carbohydrate complex）. Finally, despite discussions about their effectiveness, pro/prebiotics and some other additives have shown some potential in reducing enteric problems. Alternatives to antibiotics are only useful, however, if the whole chain （reproduction stock producers, breeders, feed companies, slaughterhouses and even veterinarians） is convinced and forced into a globally consistent strategy. In the absence of such a consistent approach, both preventive and curative use of antibiotics remains the easiest and most inexpensive way to control disease in rabbit production.
基金supported by the Faculty of Tropical Medicine,Mahidol University,Thailand,Research Fund through a Research and Researcher for Industry(RRi,Grant Number PHD59I0063 for SB)TRF Grant for New Researcher(TRG,Grant Number TRG5980015 for CP)the Office of the National Research Council of Thailand-Japan Society for the Promotion of Science(JSPS)or NRCT-JSPS
文摘Objective: To evaluate the expression of DNA plasmid-harboring modified antibody gene that produces neutralizing human monoclonal antibodies against four serotypes of dengue virus(DENV) without enhancing activity in BALB/c mice. Methods: We constructed pFUSE-based vectors(pFUSE1 G7 C2hVH and pFUSE1 G7 C2hVL) containing genes encoding the variable domains of the heavy or light chain of the anti-dengue virus antibody 1 G7 C2, a human IgG1 that has been characterized for its neutralizing activity to DENV-1-4. Leucine(L) at positions 234 and 235 on the Fc CH2 domain in pFUSE1 G7 C2hVH was mutated to alanine(A)(LALA mutation) by site direct mutagenesis, and the new plasmid was termed pFUSE1 G7 C2hVHLALA. An equal amount of pFUSE1 G7 C2hVL and 1 G7 C2hG1-LALA plasmids were co-transfected into Chinese hamster ovary cells(CHO-K1) and a single dose of 100 μg 1 G7 C2hG1-LALA plasmid was intramuscularly injected, followed by electroporation in BALB/c mice. The secreted 1 G7 C2hG1-LALA antibodies in cell culture supernatant and mouse serum were examined for their biological functions, neutralization and enhancing activity. Results: The co-transfection of heavy-and light-chain 1 G7 C2hG1-LALA plasmids in CHO-K1 cells produced approximately 3 900 ng/mL human IgG and neutralized 90%-100% all four DENV, with no enhancing activity. Furthermore, the modified human IgG was produced more than 1 000 ng/mL in mouse serum on day 7 post plasmid injection and showed cross-neutralization to four DENV serotypes. Subsequently, antibody production and neutralization decreased rapidly. Nevertheless, the secreted neutralizing 1 G7 C2hG1-LALA in mouse serum demonstrated complete absence of enhancing activities to all DENV serotypes. Conclusions: These findings reveal that a new modified 1 G7 C2h G1-LALA expressing plasmid based on gene transfer is a possible therapeutic antibody candidate against DENV infection.
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.
基金covered by the National Research Agency(AEI,Spain)(grant number:PID2019-103969RB-C33)to Jos e M.Cerd a-Reverter。
文摘In this study,we investigated the transcriptional spatio-temporal dynamics of the taste 1 receptor(T1R)gene family repertoire in seabream(Sparus aurata[sa]),during larval ontogeny and in adult tissues.In early larval development,sa T1R expression arises heterochronously,i.e.the extraoral taste-related perception in the gastrointestinal tract(GIT)anticipates first exogenous feeding(at 9 days post hatching[dph]),followed by the buccal/intraoral perception from 14 dph onwards,supporting the hypothesis that the early onset of the molecular machinery underlying sa T1R expression in the GIT is not induced by food but rather genetically hardwired.During adulthood,we characterized the expression patterns of sa T1R within specific tissues(n=4)distributed in oropharingeal,GIT and brain regions substantiating their functional versatility as chemosensory signaling players to a variety of biological functions beyond oral taste sensation.Further,we provided for the first time direct evidences in fish for m RNA coexpression of a subset of sa T1R genes(mostly sa T1R3,i.e.the common subunit of the heterodimeric T1R complexes for the detection of“sweet”and“umami”substances),with the selected gut peptides ghrelin(ghr),cholecystokinin(cck),hormone peptide yy(pyy)and proglucagon(pg).Each peptide defines the enteroendocrine cells(ECCs)identity,and establishes on morphological basis,a direct link for T1R chemosensing in the regulation of fish digestive processes.Finally,we analyzed the spatial gene expression patterns of 2 taste signaling components functionally homologous to the mammalian G(i)a subunit gustducin,namely sa G(i)a1 and sa G(i)a2,and demonstrated their co-localization with the sa T1R3in EECs,thus validating their direct involvement in taste-like transduction mechanisms of the fish GIT.In conclusion,data provide new insights in the evolutionary conservation of gut sensing in fish suggesting a conserved role for nutrient sensors modulating entero-endocrine secretion.
基金financially supported by the China Agriculture Research System of MOF and MARA(CARS-46)Lucta(Guangzhou)Flavours Co.,Ltd.
文摘The present study investigated the potential effects of an umami taste stimulator(UTS)on largemouth bass(Micropterus salmoides)fed a high plant protein diet.Two isonitrogenous and isolipidic diets were formulated with 40%fishmeal(positive control,PC)and 25%fishmeal(negative control,NC),respectively.The other three diets were supplemented with 0.10%,0.15%and 0.20%of the UTS based on NC group.Five groups of fish(mean initial weight 29.82±0.04 g)were fed twice daily for 64 days.The results indicated that feed intake,growth performance,and taste receptor and enteroendocrine-related genes expression(pyya,t1r1 and ghrl)in NC group were significantly reduced compared with PC group,which were improved with dietary supplementation of the UTS(at 0.15%and 0.20%).In addition,muscle thickness of midgut and hindgut,villus length of hindgut in the NC group were reduced compared to the PC group,but they improved with dietary UTS supplementation.Also,antioxidant capacity,and expression of genes involved in peptide and amino acid transport and target of rapamycin(TOR)pathway were reduced in the NC group compared to the PC group.However,the inclusion of UTS improved the total antioxidant capacity,superoxide dismutase and catalase compared with the NC group.Peptide and amino acid transporters(lat1,lat2,snat2 and pept2)and TOR pathway(tor,akt1,4ebp1 and s6)related genes’expression were also ameliorated by UTS addition compared to the NC group.In summary,UTS supplementation could improve the appetite,growth performance,and health status of largemouth bass,and the recommended additional amount of UTS was 0.15%-0.20%.
