Two hundred and sixty four broiler breeder hens of 32 weeks of age were distributed randomly in four dietary treatments. The dietary treatments were T0: Broiler breeder ration containing 40 ppm zinc (basal 29.8 ppm + ...Two hundred and sixty four broiler breeder hens of 32 weeks of age were distributed randomly in four dietary treatments. The dietary treatments were T0: Broiler breeder ration containing 40 ppm zinc (basal 29.8 ppm + 10.2 ppm inorganic zinc), T1: T0 + organic zinc (zinc methionine) @ 20 ppm, T2: T0 + organic zinc @ 40 ppm and T3: T0 + organic zinc @ 60 ppm. The experiment was continued from 32 to 48 weeks of age. At 48 weeks, the weight of lymphoid organs, zinc levels in organs and immunity response were determined. The faecal zinc level was determined at monthly interval. The weight lymphoid organs of different treatment groups (both organic and inorganic zinc fed groups) of the broiler breeders did not differ significantly (P > 0.05). The cellular immune response of breeder birds to PHA-P was significantly (P 0.05) higher in group T3 than the rest of treated groups. The antibody titre to SRBC differed among the treated groups. The zinc content of serum of broiler breeders of all the groups did not differ significantly (P > 0.05) in all the periods of study. Zinc content in liver and tibia of broiler breeders in different dietary treatments of zinc differed significantly (P 0.05) with higher levels were obtained on increasing zinc concentration in the diet. The zinc level in the spleen and kidney of the broiler breeders in different dietary treatments did not differ significantly (P > 0.05). The average zinc content in the faeces of broiler breeder during 35 to 43 week of age did not differ significantly (P > 0.05) among the treated groups. At 48 weeks of age, zinc content of the faeces of T3 was found to be significantly (P 0.05) higher than the rest of treated groups. Similarly, during the overall experimental period analysis, it was found that zinc levels in the faeces of T2 and T3 were significantly (P 0.05) higher than T1 and T0.展开更多
The spread of antibiotic resistance, whether in the community or in the hospital, has recently become a major public health problem. Moreover, livestock seems to be a reservoir of resistant microorganisms such as porc...The spread of antibiotic resistance, whether in the community or in the hospital, has recently become a major public health problem. Moreover, livestock seems to be a reservoir of resistant microorganisms such as porcine methicillin resistant Staphylococcus aureus (P-MRSA) whose carriage and transmission was mainly demonstrated in persons with occupational exposure to pigs. Much uncertainty remains about the public health implications of P-MRSA. To address concerns that exist regarding the zoonotic risk that pig carriers pose to breeders, the prevalence of P-MRSA in pigs and pig breeders was determined among 152 pig breeders in three regions of Cameroon. Materials and Method: Participants in this study came from Adamawa, Far North and Littoral regions of Cameroon. A total of 152 pig breeders or farm workers participated in this study. After having collected some social and cultural data with the aid of a questionnaire, nasal swabs were collected from pigs (n = 275) and their breeders using the standard collection procedures and placed in cooler containing cold accumulators. For each sample, microbiological assays were done as well as antibiotic susceptibility tests. Results: MRSA was isolated from 25 out of 275 pigs sampled (9.09%) and from 32 out of 152 (21.05%) pig breeders sampled;33 breeders (21.71%) were carriers of S. aureus including 32 MRSA and one MSSA. The prevalence of MRSA nasal carriage was 21.05% ± 6.48. A significant negative association between body protection and nasal carriage of MRSA (OR = 0.29, 95% CI [0.093;0.93];p = 0.04) was observed. In each region, similar strains of MRSA were isolated both in pigs and their breeders with the same antibiotic resistant profile. Conclusion: The prevalence of MRSA though not high compared to European countries warrants further research as data on this zoonosis is scarce in our context. As such, transmission of MRSA from pigs to pig breeders or vice-versa constitutes a real danger, and this relationship may be a starting point for MRSA contamination in the community. Moreover, proper use of body protections and antibiotic medications as recommended will be a better protective measure against nasal MRSA carriage.展开更多
Salmonella is a ubiquitous pathogen which, in addition to causing poultry diseases, has a growing zoonotic impact. It has demanded the implementation of diverse control strategies, in which vaccines play a major role....Salmonella is a ubiquitous pathogen which, in addition to causing poultry diseases, has a growing zoonotic impact. It has demanded the implementation of diverse control strategies, in which vaccines play a major role. The understanding of the immune pathways elicited by the different vaccines is important, contributing for the establishment of strong immune correlates of protection, for instance. With the purpose of determining the dynamics of the humoral and cellular immune responses to vaccination, broiler breeders (Cobb Slow) were immunized with live or inactivated vaccines against Salmonella Enteritidis. Lymphocyte and macrophage subsets were analyzed in the peripheral blood by flow cytometry and antigen-specific circulating IgY and mucosal IgA were quantified. The markers analyzed by flow cytometry were CD8/CD28, CD4/TCRVβ1, Kul/ MHC II and Bu-1. Both live and inactivated vaccines induced an increase in the proportion of circulating monocytes (Kul+MHCII+) in some time points compared to non-vaccinated controls. However, whereas the live vaccine leads to an increase in CD8-CD28+ and Bu-1+ lymphocytescompared to the control group, the inactivated vaccine prompteda reduction in the percentage of severalleucocyte subsets (Kul-MHCII+, Bu-1+, CD8+CD28+, CD8-CD28+, CD4+TCRVβ1-, CD4+TCRVβ1+, CD4-TCRVβ1+) after the boost dose. Both vaccines induced specific serum IgY and mucosal IgA production;however, the inactivated vaccine stimulated higher titers in a shorter period. These results contribute to the understanding of mechanisms of action of live and inactivated Salmonella vaccines in chickens.展开更多
Background: Dietary canthaxanthin(CX), 25-hydroxycholecalciferol(25-OH-D3) and vitamins have been widely reported to be involved in productive and reproductive performance of broiler breeders. However, limited in...Background: Dietary canthaxanthin(CX), 25-hydroxycholecalciferol(25-OH-D3) and vitamins have been widely reported to be involved in productive and reproductive performance of broiler breeders. However, limited information is available for duck breeders. In this study, a total of 1,560 Cherry Valley SM3 duck breeder females and 312 males were used to assess if the addition of CX and 25-OH-D3 could increase the performance of duck breeders under two different dietary vitamin regimens. Four diets were used under a 2 × 2 factorial arrangement with 2 kinds of vitamin premixes(REGULAR and HIGH; HIGH premix had higher levels of all vitamins except K3 than REGULAR premix), and with or without the supplementation of the mixture of CX(6 mg/kg) and 25-OH-D3(0.069 mg/kg). The ducks were fed ad libitum with pelleted diets based on corn-soybean meal from 38 to 77 wk of age.Results: HIGH vitamin premix decreased malondialdehyde(MDA) level(P 〈 0.001) of egg yolk, increased hatchability of fertile eggs(P = 0.029), increased hatchability of total eggs(P = 0.029), and decreased serum protein carbonyl level(P = 0.037) of breeder males. The mixture of CX and 25-OH-D3 increased serum calcium of breeder females(P = 0.010), decreased the cracked egg rate(P = 0.001), increased the pigmentation of egg yolk(P 〈 0.001)and male bill(P 〈 0.001), and decreased MDA level of egg yolk(P 〈 0.001) and male serum(P = 0.034). Interactive effects were observed in cracked egg rate(P = 0.038), shell thickness(P = 0.011) and serum phosphorus(P = 0.026)of breeder females. HIGH vitamin premix together with the mixture of CX and 25-OH-D3 decreased cracked egg rate and increased shell thickness of duck breeders. Serum phosphorus was decreased in duck breeder females fed REGULAR vitamin premix without the addition of the CX and 25-OH-D3 mixture.Conclusions: Dietary HIGH vitamin premix increased antioxidant status of eggs and breeder males, and increased hatchability. The mixture of CX and 25-OH-D3 enhanced egg shell quality, and promoted pigmentation and antioxidant status of eggs and breeder males.展开更多
The effects of supplementing a blend of organic acids (OA) and a lactic acid bacteria (LAB) based-probiotic on egg to chick weight loss (%) and Salmonella spp. recovery counts in the litter of commercial broiler breed...The effects of supplementing a blend of organic acids (OA) and a lactic acid bacteria (LAB) based-probiotic on egg to chick weight loss (%) and Salmonella spp. recovery counts in the litter of commercial broiler breeders were examined in three independent trials during the years 2013, 2014 and 2015. In each trial, ten thousand birds were divided into two groups of 5000 birds (4500 females and 500 males in each group): Control non-treated group, receiving regular water or treated group, receiving OA and probiotic in the drinking water from 25 to 35 weeks of age. During the ten weeks of evaluation, one thousand fertile eggs or hatched chickens in each trial respectively, were evaluated to obtained, hatching set weight, transferred egg weight, and hatching chick weight, to estimate the difference between egg to chick weight loss (%). Besides, in trial 2 (2014) and trial 3 (2015), litter samples were collected to evaluate Salmonella spp. counts. The supplementation of OA and probiotic during ten consecutive weeks significantly decreased the egg to chick weight loss (%) when compared with the control non-treated groups in all three trials evaluated. Interestingly, at the end of the trials 2 and 3, no counts of Salmonella spp. in the litter were detected. In contrast, control-non treated groups resulted in 4.30 and 4.24 Log10 of Salmonella spp. in trials two and three respectively. The results of the present study suggest that supplementation of OA and a LAB-probiotic for ten consecutive weeks decrease the egg to chick weight loss (%) and reduce Salmonella spp. counts in the litter of commercial broiler breeders. Higher initial body weight in broiler chickens and reduction of Salmonella spp., clearly justify the use of the combination of these products, as alternatives to antibiotics.展开更多
[Objective]The paper was to verify whether chestnut bee pollen can be used as feed for breeding chickens and its appropriate addition proportion.[Method]A total of 92444-week-old Ross 308 broiler breeders of parent ge...[Objective]The paper was to verify whether chestnut bee pollen can be used as feed for breeding chickens and its appropriate addition proportion.[Method]A total of 92444-week-old Ross 308 broiler breeders of parent generation with a male to female ratio of 1∶10 were randomly divided into 4 groups,with 3 replicates in each group and 7 cocks and 70 hens in each replicate.The broiler breeders in the control group were fed with the basal diet,and those in experimental groups were fed with the diets supplemented with 0.5%,1.0%and 1.5%chestnut bee pollen.The feeding trial lasted 35 d.[Result]Addition of chestnut bee pollen at different proportions improved the laying rate of breeder hens in different degrees.The experimental group supplemented with 1.5%chestnut bee pollen increased the laying rate by 9.1%,reduced the rate of unqualified eggs(broken eggs,cracked eggs,thin shelled eggs and hard shelled eggs)by 71.4%,increased the fertilization rate of hatching eggs and healthy chick rate by 4.4%and 5.2%,and improved the concentrations of testosterone(T),follicle stimulating hormone(FSH)and luteinizing hormone(LH)in breeder cocks by 60.8%,32.3%and 61.4%,respectively.Statistical analysis showed that the results were significantly different.[Conclusion]Addition of chestnut bee pollen at certain concentration can improve the reproductive performance of breeder cocks and breeder hens,and improve the body immunity.展开更多
Hetero-element doped lithium orthosilicates have been considered as advanced tritium breeders due to the superior performances.In this work,Li_(4)Si_(1-x)Ti_(x)O_(4) ceramics were prepared by proprietary hydrothermal ...Hetero-element doped lithium orthosilicates have been considered as advanced tritium breeders due to the superior performances.In this work,Li_(4)Si_(1-x)Ti_(x)O_(4) ceramics were prepared by proprietary hydrothermal process and multistage reactive sintering.The reaction mechanism of Li_(4)Si_(1-x)Ti_(x)O_(4) was put forward.XRD and SEM analyses indicate that insertion of Ti leads to lattice expansion,which promotes the grain growth and changes the fracture mode.The compressive tests show that the crush load increases almost four times by increasing x from 0 to 0.2.However,the thermal conductivity and ionic conductivity are the best when x=0.05 and x=0.1,respectively.Thermal cycling stability of Li_(4)Si_(1-x)Ti_(x)O_(4) pebbles was further appraised through investigating the changes of microstructure and crush load.After undergoing thermal cycling,the Li_(4)Si_(1-x)Ti_(x)O_(4) still show higher crush load compared with Li_(4)SiO_(4),despite Ti segregation in some samples.The x=0.05 sample exhibits excellent thermal cycling stability.In summary,proper amount of Ti doping can improve the crush load,thermal and ionic conductivity,and thermal cycling stability of Li_(4)SiO_(4).展开更多
Colony cages for natural mating have been applied on many layer breeder farms.However,feather pecking and cloacal cannibalism are considered as prominent problems for these systems.This study aimed to investigate the ...Colony cages for natural mating have been applied on many layer breeder farms.However,feather pecking and cloacal cannibalism are considered as prominent problems for these systems.This study aimed to investigate the effects on feather pecking and vent pecking behaviors by providing layer breeders with nest boxes(0.90 m L×0.40 m W×0.60 m H)in colony cages for natural mating(4.80 m L×1.20 m W×0.71 m H).Video recording and artificial observation were adopted.The results showed that the usage of nest boxes gradually increased from the beginning of nest boxes providing at the age of 37 weeks to the end of the experiment at the age of 55 weeks.The utilization rates of nest boxes were 36.75%,44.75%and 50.38%at the ages of 41 weeks,47 weeks and 53 weeks,respectively.The hens in the cages without nest boxes showed significantly more frequent gentle feather pecks(both given and received)than hens in the cages with nest boxes at the ages of 41 weeks,47 weeks and 53 weeks.A decreasing trend of gentle feather pecking frequency(both given and received)was found with the increasing age for both the two groups.No significant difference was found in the number of given or received severe feather pecks at the age of 41 weeks.The hens in the cages without nest boxes showed a significantly higher frequency of given and received severe feather pecks than hens in the cages with nest boxes at the ages of 47 weeks and 53 weeks(p<0.05).Both cannibalistic injury occurrence and mortality rate in the cages with nest boxes were significantly lower than those in the cages without nest boxes.In conclusion,providing nest boxes in colony cages for natural mating could decrease abnormal pecking behaviors and improve animal welfare conditions of layer breeders.展开更多
Nuclear fusion energy is considered as a clean and safe energy source.As the fuel of deuterium-tritium(D-T)fusion reactor,T must be produced by the reaction between neutron and lithium(Li)in the breeders.The blanket o...Nuclear fusion energy is considered as a clean and safe energy source.As the fuel of deuterium-tritium(D-T)fusion reactor,T must be produced by the reaction between neutron and lithium(Li)in the breeders.The blanket of fusion reactor will work in a high-temperature and radioactive environment.The long-term contact between T breeders and structural materials in such a harsh environment will result in corrosion and microstructure modification of material surfaces,and then affect the mechanical properties and thermal conductivity of materials.To protect the structural materials from corrosion,coatings are applied to their surface.In addition,the coating also plays a role in preventing T permeation.The compatibility of T breeder materials with structural materials and coatings in the breeding blanket has always been a concern.In this paper,the up-to-date data on liquid and solid blanket of fusion reactors,the interaction behavior of T breeders with candidate structural materials,including reduced activation ferritic/martensitic steel,oxide dispersion-strengthened steel,silicon carbide and vanadium alloy,and coatings are reviewed.The corrosion mechanism is also expounded.Furthermore,the corrosion behavior between different types of materials is compared comprehensively.At the end,the research and development prospects on this topic are suggested.展开更多
An exogenous avian leukosis virus (ALV) strain SDAU09C1 was isolated in DF-1 cells from one of 240 imported 1-day-old white meat-type grand parent breeder chicks. Inoculation of SDAU09C1 in ALV-free chickens induced a...An exogenous avian leukosis virus (ALV) strain SDAU09C1 was isolated in DF-1 cells from one of 240 imported 1-day-old white meat-type grand parent breeder chicks. Inoculation of SDAU09C1 in ALV-free chickens induced antibody reactions specific to subgroup A or B. But gp85 amino acid sequence comparisons indicated that SDAU09C1 fell into subgroup A; it had homology of 88.8%-90.3% to 6 reference strains of subgroup A, much higher compared to other subgroups including subgroup B. This is the first report for ALV of subgroup A isolated from imported breeders.展开更多
Molecular markers,genome sequencing and genome editing are considered as efficient tools to accomplish demands of plant breeders for crop improvement programs.Morphological and biochemical markers have not been extens...Molecular markers,genome sequencing and genome editing are considered as efficient tools to accomplish demands of plant breeders for crop improvement programs.Morphological and biochemical markers have not been extensively used as these are greatly influenced by environmental factors.Different molecular markers and sequencing techniques are routinely used in evaluation of genetic diversity and evolutionary relationship,accurate classification or taxonomy,characterization of germplasm,identification of hybrids and phylogenetic studies.Desired and undesired traits controlled by genes can be identified through different molecular markers technology all over the globe.These molecular markers are well established and have successfully been used for genetic analysis of different plants during last two decades.Recently,advanced techniques of molecular markers have been developed,which provide advance genotypic platform and tends to merge valuable properties of many basic systems.New class of markers also includes little modifications in basic methods to enhance the sensitivity and resolution.Biotechnologists,plant breeders and strong investment are strongly linked for crop improvement purposes.Current review provides detailed description of different markers,genome sequencing and genome editing that have been utilized for different genetic analyses of horticultural crops.Genome editing technologies based on CRISPR/Cas are now successfully applied in horticultural crops.Moreover,current review encourages the use of molecular marker technology for DNA fingerprinting,bar coding,sequencing,re-sequencing QTL mapping,genome association mapping and genome editing.It is need of time that diverse germplasm should be identified with different molecular techniques and further utilized in breeding purposes to achieve higher yielding and resistant cultivars against biotic and abiotic stresses.展开更多
A study was conducted to determine the effects of dietary digestible amino acids of feedstuffs and true metabolizable energy corrected for nitrogen on broiler breeder performance in 50 weeks to 64 weeks of age. 140 fe...A study was conducted to determine the effects of dietary digestible amino acids of feedstuffs and true metabolizable energy corrected for nitrogen on broiler breeder performance in 50 weeks to 64 weeks of age. 140 females and 20 males broiler breeders in 4 treatments with 5 replicates (7 females with a male) were used in the form of a completely randomized trial design 2 ~ 2 factorial. Four experimental diets were formulation based on two factors, first factor was included, two types of Apparent and True Metabolizable Energy corrected for Nitrogen (AMEn and TMEn) and the second factor was included, two types of Total Amino Acids (TAA) and Digestible (DAA) of feedstuffs. The result showed that egg weight, egg production (%) and egg mass (g/hen/day) was significantly different which was affected by diets formulation based on energy and interaction between energy and amino acids (P 〈 0.01). Treatment 2 (AMEn + DAA) was at the highest level significantly different (P 〈 0.01) in egg weight 68.97 g, egg production 62.45%, and egg mass 43. i g/hen/day. Hatching eggs were significantly different which was affected by diet formulation based on amino acids. Fertility, hatchability and number of chicks per hen were significant different, that were affected by diet formulation based on energy (P 〈 0.05). Interaction between two factors, were significantly different in two reproductive traits fertility and hatchability (P 〈 0.05). This experiment showed that diet formulation based on AMEn and DAA for broiler breeder was better and significant on performance.展开更多
Mycoplasma synoviae (MS) is an economically important pathogenic agent of chickens, causing air sacculitis and synovitis. The diagnosis and monitoring of M. synoviae infection is usually made using serological assay...Mycoplasma synoviae (MS) is an economically important pathogenic agent of chickens, causing air sacculitis and synovitis. The diagnosis and monitoring of M. synoviae infection is usually made using serological assays, while confirmative diagnosis is made by isolation and identifcation of the organism, because of the cross reaction between M. gallisepticum and M. synoviae. This study was conducted from 2011 to 2013 during which l l broiler breeder flocks were sampled. These farms were located in all regions of morocco, The sampling was conducted as follows: Farms were visited on day one old chicks "day of importation from Europe". 20 to 60 "chicks" were randomly sampled. At the age of 8, 16, 32 and 56 weeks, 60 blood samples and 60 tracheal swabs were collected at each sampling. The serological screening was performed using Rapid Slide Agglutination (RSA) according the OIE protocol and Indirect EL1SA (IDEXX) according the manufacturer's instructions. The molecular diagnosis was performed using a commercial kit of a duplex real time PCR (Life Biotechnology). The results revealed that one day old chicks were negative to MS by RSA and PCR, however they have a variable stock of maternal antibodies (Ig-Y) detected by iELISA. The seroprevalence found by RSA is variable and increase with the age (Sth week: 55%, 16th week: 91%, 32tb and 56th week: 100%), the same profile was traced by PCR (Sth week: 36%, 16th week: 64%, 32th week: 82%, 56th week: 100%), however, all farms were positive by iELISA, from the first day to 56th weeks. These results show that MS infections are very frequent and very widespread among poultry breeder flocks, and showed a perfect agreement between serological tests and Real time PCR starting from 32th week of age.展开更多
Two experiments were conducted to investigate the effect of in ovo zinc (Zn) injection on the embryonic development, tissue Zn contents, antioxidation and related gene expressions of fertilized eggs of Arbor Acres b...Two experiments were conducted to investigate the effect of in ovo zinc (Zn) injection on the embryonic development, tissue Zn contents, antioxidation and related gene expressions of fertilized eggs of Arbor Acres broiler breeders. Experiment 1 was conducted to determine an optimal embryonic age for early in ovo injection. A total of 720 fertilized eggs with similar weights were randomly allotted to 4 treatments with 6 replicates per treatment and 30 eggs per replicate in a completely randomized design. The eggs were injected with 0.1 mL sterilized water at 3, 6 and 9 embryonic days of incubation (E3, E6 and E9) or non-injection (the control), respectively. The results from experiment 1 showed that E3 and E6 injections increased (P〈0.05) the embryonic mortalities, and decreased (P〈0.05) hatchabilities compared to the non-injected control, but no differences (P〉0.05) between E9 injection and the non-injected control were observed in either embryonic mortality or hatchability. The findings suggest that the E9 is the optimal embryonic age for early in ovo injection. In experiment 2, a total of 672 fertilized eggs with similar weights were randomly allocated to 7 treatments with 6 replicates per treatment and 16 eggs per replicate in a completely randomized design. The eggs were injected with 0 (the negative control), 50, 100, 150, 200, or 250 μg Zn/egg as reagent grade ZnSO4.7H20 in a 0.1-mL solution, or non-injection (the positive control), respectively at E9-10. The results from the experiment 2 demonstrated that no differences (P〉0.05) among 50 and 100 μg Zn/egg groups and the negative control were observed in the embryonic mortality and hatchability, however, the injection of 200 μg Zn/egg increased (P〈0.05) the embryonic mortality, and injections of 150 and 200 μg Zn/egg decreased (P〈0.05) hatchabilities compared with the controls. The embryonic tibia Zn contents at E20 were increased (P〈0.05) by injections of 150, 200 and 250μg Zn/egg. Zinc injection did not affect (P〉0.05) malonaldehyde (MDA) contents, copper- and Zn- containing superoxide dismutase (CuZnSOD) activities and mRNA expression levels in the liver and heart of chick embryos at E15 and E20. Compared with the negative control, injections of 50, 150 and 200 μg Zn/egg up-regulated (P〈0.05) themetallothionein (MT) mRNA expression levels in the embryonic liver at E20. These results indicated that in ovo Zn injections increased Zn contents in the embryonic tibia and MT mRNA expression levels in the embryonic liver at E20, however, injections of 150-200 μg Zn/egg were harmful to the embryonic development.展开更多
For the solid blanket concept of helium cooled ceramic breeder (HCCB) demonstration fusion power plant (DEMO), a feasible blanket structure with configuration 2×X is proposed as considering relatively low tempera...For the solid blanket concept of helium cooled ceramic breeder (HCCB) demonstration fusion power plant (DEMO), a feasible blanket structure with configuration 2×X is proposed as considering relatively low temperature limit of neutron multiplier beryllium pebbles. Based on that, preliminary design for the typical blanket module of HCCB DEMO has been carried out and verified by thermal-hydraulic analysis and structural analysis. Furthermore, the specific relationship of maximum temperature depended on the surface heating of blanket key part first wall (FW) is also analyzed.展开更多
[Objective] To investigate effects of different dietary crude protein levels on reproductive performance and find out the optimal additive proportion of crude protein. [Method] A total of 45 New Yangzhou breeder roost...[Objective] To investigate effects of different dietary crude protein levels on reproductive performance and find out the optimal additive proportion of crude protein. [Method] A total of 45 New Yangzhou breeder roosters at 21 weeks old were sampled and divided into three groups, namely, low-protein diet group, medium-protein diet group and high-protein diet group. They were fed with diets respectively at crude protein levels of 17.23%, 13.04% and 11.32%. The sperm volume, testicular traits and levels of reproductive hormones were analyzed during the whole repro- ductive period. [Result] The sperm volume, sperm motility and sperm density of the medium-protein diet group were higher than that of the other two groups, and the sperm deformity rate of the medium-protein diet group was lowest. The rooster's testicular traits including weight, volume and testis indexes were not significantly affected by different protein levels, but the testis shrank slowly with aging ( P 〈 0.05). The levels of testosterone (T), luteinizing hormone (LH) and follicule stimulating hormone (FSH) in plasma were respectively 6.34%, 19.64% and 3.88% higher in the lowprotein diet group than in the medium-protein diet group, and these indexes were respectively 7.20%, 17.54% and 9.84% higher in the low-protein diet group than in the high-protein diet group. But all these differences were not significant. [ Conclusion] The breeder roosters fed with the diet at the crude protein level of 13.04% show better reproductive performance and economic efficiency.展开更多
The aim of this work was to compare the use of local intrauterine moist heat infusion to intrauterine antibiotics infusion, for treatment of subclinical endometritis which affects reproduction and milk production. 42 ...The aim of this work was to compare the use of local intrauterine moist heat infusion to intrauterine antibiotics infusion, for treatment of subclinical endometritis which affects reproduction and milk production. 42 repeat breeder cows were divided into 4 groups, group 1 was the untreated control (=10 cows). Group 2 (=10 cows) was treated by 50 ml of Oxytetracycline 5% intrauterine for three successive weeks. Group 3 (=10 cows) intrauterine infusion with 30 ml saline adding to them 10 ml Gentamycin 10% and 10 ml penicillin and streptomycin for three successive weeks. Group 4 (=12 cows) intrauterine infusion with 50 ml sterile boiling water (≈100°C) was applied directly to the uterus for only one time. Leukogram was done before and after treatment, it showed leukocytosis and neutrophilia in all the study groups. After treatment for 36 hours and one week, there were no significant changes in the leukogram results of groups 1, 2 and 3. While in Group 4 showed decreasing in numbers of leukocytes (11.92 ± 0.75) and neutrophils (0.87 ± 0.16) to its normal limits after 36 hours and one-week post-treatment. Our new method gave the highest cumulative pregnancy rate 83.3% while other groups using antibiotics or antibiotics with saline gave lower pregnancy rate 40% and 50% respectively (P > 0.001). We named this new treatment method “Samia-treat;SAT”. SAT is a whole new and effective treatment for cases of repeat breeder which are caused by SCE in dairy cows;it caused increase in reproductive performance and cumulative pregnancy rate without over use of antibiotics.展开更多
The objective of this study is to presume cesium corrosion process and its dominant factors in SUS316 steel, a fuel cladding material for fast breeder reactor application, based on both experimental results of cesium ...The objective of this study is to presume cesium corrosion process and its dominant factors in SUS316 steel, a fuel cladding material for fast breeder reactor application, based on both experimental results of cesium corrosion out-pile test and thermodynamic consideration. The cesium corrosion test was performed in simulated environment of high burn-up fuel pin. And main corrosion products in the specimen after the corrosion test were specified by TEM (transition electron microscopy) and SEM (scanning electron microscopy) in order to formulate a hypothesis of the cesium corrosion process. At the end of this study, it was found that the dominant factors of the corrosion process are the amount of cesium on the surface of the specimen, chromium content in the alloy, the supply rate of oxygen and temperature.展开更多
India,under its breeding blanket R&D program for DEMO,is focusing on the development of two tritium breeding blanket concepts;namely the lead-lithium-cooled ceramic breeder and the helium-cooled ceramic breeder(HC...India,under its breeding blanket R&D program for DEMO,is focusing on the development of two tritium breeding blanket concepts;namely the lead-lithium-cooled ceramic breeder and the helium-cooled ceramic breeder(HCCB).The study presented in this paper focuses on the neutronic design analysis and optimization from the tritium breeding perspective of the HCCB blanket.The Indian concept has an edge-on configuration and is one of the variants of the helium-cooled solid breeder blanket concepts proposed by several partner countries in ITER.The Indian HCCB blanket having lithium titanate(Li2TiO3)as the tritium breeder and beryllium(Be)as the neutron multiplier with reduced-activation ferritic/martensitic steel structure aims at utilizing the low-energy neutrons at the rear part of the blanket.The aim of the optimization study is to minimize the radial blanket thickness while ensuring tritium self-sufficiency and provide data for further neutronic design and thermal-hydraulic layout of the HCCB blanket.It is found that inboard and outboard blanket thicknesses of 40 cm and 60 cm,respectively,can give a tritium breeding ratio(TBR)>1.3,with 60%6Li enrichment,which is assumed to be sufficient to cover potential tritium losses and associated uncertainties.The results also demonstrated that the Be packing fraction(PF)has a more profound impact on the TBR as compared to 6Li enrichment and the PF of Li2TiO3.展开更多
文摘Two hundred and sixty four broiler breeder hens of 32 weeks of age were distributed randomly in four dietary treatments. The dietary treatments were T0: Broiler breeder ration containing 40 ppm zinc (basal 29.8 ppm + 10.2 ppm inorganic zinc), T1: T0 + organic zinc (zinc methionine) @ 20 ppm, T2: T0 + organic zinc @ 40 ppm and T3: T0 + organic zinc @ 60 ppm. The experiment was continued from 32 to 48 weeks of age. At 48 weeks, the weight of lymphoid organs, zinc levels in organs and immunity response were determined. The faecal zinc level was determined at monthly interval. The weight lymphoid organs of different treatment groups (both organic and inorganic zinc fed groups) of the broiler breeders did not differ significantly (P > 0.05). The cellular immune response of breeder birds to PHA-P was significantly (P 0.05) higher in group T3 than the rest of treated groups. The antibody titre to SRBC differed among the treated groups. The zinc content of serum of broiler breeders of all the groups did not differ significantly (P > 0.05) in all the periods of study. Zinc content in liver and tibia of broiler breeders in different dietary treatments of zinc differed significantly (P 0.05) with higher levels were obtained on increasing zinc concentration in the diet. The zinc level in the spleen and kidney of the broiler breeders in different dietary treatments did not differ significantly (P > 0.05). The average zinc content in the faeces of broiler breeder during 35 to 43 week of age did not differ significantly (P > 0.05) among the treated groups. At 48 weeks of age, zinc content of the faeces of T3 was found to be significantly (P 0.05) higher than the rest of treated groups. Similarly, during the overall experimental period analysis, it was found that zinc levels in the faeces of T2 and T3 were significantly (P 0.05) higher than T1 and T0.
文摘The spread of antibiotic resistance, whether in the community or in the hospital, has recently become a major public health problem. Moreover, livestock seems to be a reservoir of resistant microorganisms such as porcine methicillin resistant Staphylococcus aureus (P-MRSA) whose carriage and transmission was mainly demonstrated in persons with occupational exposure to pigs. Much uncertainty remains about the public health implications of P-MRSA. To address concerns that exist regarding the zoonotic risk that pig carriers pose to breeders, the prevalence of P-MRSA in pigs and pig breeders was determined among 152 pig breeders in three regions of Cameroon. Materials and Method: Participants in this study came from Adamawa, Far North and Littoral regions of Cameroon. A total of 152 pig breeders or farm workers participated in this study. After having collected some social and cultural data with the aid of a questionnaire, nasal swabs were collected from pigs (n = 275) and their breeders using the standard collection procedures and placed in cooler containing cold accumulators. For each sample, microbiological assays were done as well as antibiotic susceptibility tests. Results: MRSA was isolated from 25 out of 275 pigs sampled (9.09%) and from 32 out of 152 (21.05%) pig breeders sampled;33 breeders (21.71%) were carriers of S. aureus including 32 MRSA and one MSSA. The prevalence of MRSA nasal carriage was 21.05% ± 6.48. A significant negative association between body protection and nasal carriage of MRSA (OR = 0.29, 95% CI [0.093;0.93];p = 0.04) was observed. In each region, similar strains of MRSA were isolated both in pigs and their breeders with the same antibiotic resistant profile. Conclusion: The prevalence of MRSA though not high compared to European countries warrants further research as data on this zoonosis is scarce in our context. As such, transmission of MRSA from pigs to pig breeders or vice-versa constitutes a real danger, and this relationship may be a starting point for MRSA contamination in the community. Moreover, proper use of body protections and antibiotic medications as recommended will be a better protective measure against nasal MRSA carriage.
文摘Salmonella is a ubiquitous pathogen which, in addition to causing poultry diseases, has a growing zoonotic impact. It has demanded the implementation of diverse control strategies, in which vaccines play a major role. The understanding of the immune pathways elicited by the different vaccines is important, contributing for the establishment of strong immune correlates of protection, for instance. With the purpose of determining the dynamics of the humoral and cellular immune responses to vaccination, broiler breeders (Cobb Slow) were immunized with live or inactivated vaccines against Salmonella Enteritidis. Lymphocyte and macrophage subsets were analyzed in the peripheral blood by flow cytometry and antigen-specific circulating IgY and mucosal IgA were quantified. The markers analyzed by flow cytometry were CD8/CD28, CD4/TCRVβ1, Kul/ MHC II and Bu-1. Both live and inactivated vaccines induced an increase in the proportion of circulating monocytes (Kul+MHCII+) in some time points compared to non-vaccinated controls. However, whereas the live vaccine leads to an increase in CD8-CD28+ and Bu-1+ lymphocytescompared to the control group, the inactivated vaccine prompteda reduction in the percentage of severalleucocyte subsets (Kul-MHCII+, Bu-1+, CD8+CD28+, CD8-CD28+, CD4+TCRVβ1-, CD4+TCRVβ1+, CD4-TCRVβ1+) after the boost dose. Both vaccines induced specific serum IgY and mucosal IgA production;however, the inactivated vaccine stimulated higher titers in a shorter period. These results contribute to the understanding of mechanisms of action of live and inactivated Salmonella vaccines in chickens.
基金National and Sichuan Provincial Science and Technology Projects(2014BAD13B02,2014NZ0030 and 2013NC0047)Academy of Kechuang Feed Industry in SichuanDSM(China)Ltd
文摘Background: Dietary canthaxanthin(CX), 25-hydroxycholecalciferol(25-OH-D3) and vitamins have been widely reported to be involved in productive and reproductive performance of broiler breeders. However, limited information is available for duck breeders. In this study, a total of 1,560 Cherry Valley SM3 duck breeder females and 312 males were used to assess if the addition of CX and 25-OH-D3 could increase the performance of duck breeders under two different dietary vitamin regimens. Four diets were used under a 2 × 2 factorial arrangement with 2 kinds of vitamin premixes(REGULAR and HIGH; HIGH premix had higher levels of all vitamins except K3 than REGULAR premix), and with or without the supplementation of the mixture of CX(6 mg/kg) and 25-OH-D3(0.069 mg/kg). The ducks were fed ad libitum with pelleted diets based on corn-soybean meal from 38 to 77 wk of age.Results: HIGH vitamin premix decreased malondialdehyde(MDA) level(P 〈 0.001) of egg yolk, increased hatchability of fertile eggs(P = 0.029), increased hatchability of total eggs(P = 0.029), and decreased serum protein carbonyl level(P = 0.037) of breeder males. The mixture of CX and 25-OH-D3 increased serum calcium of breeder females(P = 0.010), decreased the cracked egg rate(P = 0.001), increased the pigmentation of egg yolk(P 〈 0.001)and male bill(P 〈 0.001), and decreased MDA level of egg yolk(P 〈 0.001) and male serum(P = 0.034). Interactive effects were observed in cracked egg rate(P = 0.038), shell thickness(P = 0.011) and serum phosphorus(P = 0.026)of breeder females. HIGH vitamin premix together with the mixture of CX and 25-OH-D3 decreased cracked egg rate and increased shell thickness of duck breeders. Serum phosphorus was decreased in duck breeder females fed REGULAR vitamin premix without the addition of the CX and 25-OH-D3 mixture.Conclusions: Dietary HIGH vitamin premix increased antioxidant status of eggs and breeder males, and increased hatchability. The mixture of CX and 25-OH-D3 enhanced egg shell quality, and promoted pigmentation and antioxidant status of eggs and breeder males.
文摘The effects of supplementing a blend of organic acids (OA) and a lactic acid bacteria (LAB) based-probiotic on egg to chick weight loss (%) and Salmonella spp. recovery counts in the litter of commercial broiler breeders were examined in three independent trials during the years 2013, 2014 and 2015. In each trial, ten thousand birds were divided into two groups of 5000 birds (4500 females and 500 males in each group): Control non-treated group, receiving regular water or treated group, receiving OA and probiotic in the drinking water from 25 to 35 weeks of age. During the ten weeks of evaluation, one thousand fertile eggs or hatched chickens in each trial respectively, were evaluated to obtained, hatching set weight, transferred egg weight, and hatching chick weight, to estimate the difference between egg to chick weight loss (%). Besides, in trial 2 (2014) and trial 3 (2015), litter samples were collected to evaluate Salmonella spp. counts. The supplementation of OA and probiotic during ten consecutive weeks significantly decreased the egg to chick weight loss (%) when compared with the control non-treated groups in all three trials evaluated. Interestingly, at the end of the trials 2 and 3, no counts of Salmonella spp. in the litter were detected. In contrast, control-non treated groups resulted in 4.30 and 4.24 Log10 of Salmonella spp. in trials two and three respectively. The results of the present study suggest that supplementation of OA and a LAB-probiotic for ten consecutive weeks decrease the egg to chick weight loss (%) and reduce Salmonella spp. counts in the litter of commercial broiler breeders. Higher initial body weight in broiler chickens and reduction of Salmonella spp., clearly justify the use of the combination of these products, as alternatives to antibiotics.
文摘[Objective]The paper was to verify whether chestnut bee pollen can be used as feed for breeding chickens and its appropriate addition proportion.[Method]A total of 92444-week-old Ross 308 broiler breeders of parent generation with a male to female ratio of 1∶10 were randomly divided into 4 groups,with 3 replicates in each group and 7 cocks and 70 hens in each replicate.The broiler breeders in the control group were fed with the basal diet,and those in experimental groups were fed with the diets supplemented with 0.5%,1.0%and 1.5%chestnut bee pollen.The feeding trial lasted 35 d.[Result]Addition of chestnut bee pollen at different proportions improved the laying rate of breeder hens in different degrees.The experimental group supplemented with 1.5%chestnut bee pollen increased the laying rate by 9.1%,reduced the rate of unqualified eggs(broken eggs,cracked eggs,thin shelled eggs and hard shelled eggs)by 71.4%,increased the fertilization rate of hatching eggs and healthy chick rate by 4.4%and 5.2%,and improved the concentrations of testosterone(T),follicle stimulating hormone(FSH)and luteinizing hormone(LH)in breeder cocks by 60.8%,32.3%and 61.4%,respectively.Statistical analysis showed that the results were significantly different.[Conclusion]Addition of chestnut bee pollen at certain concentration can improve the reproductive performance of breeder cocks and breeder hens,and improve the body immunity.
基金supported by National Natural Science Foundation of China(No.51802257)Natural Science Foundation of Shaanxi Provincial Department of Education(18JK0570)China Postdoctoral Science Foundation(2019M663788).
文摘Hetero-element doped lithium orthosilicates have been considered as advanced tritium breeders due to the superior performances.In this work,Li_(4)Si_(1-x)Ti_(x)O_(4) ceramics were prepared by proprietary hydrothermal process and multistage reactive sintering.The reaction mechanism of Li_(4)Si_(1-x)Ti_(x)O_(4) was put forward.XRD and SEM analyses indicate that insertion of Ti leads to lattice expansion,which promotes the grain growth and changes the fracture mode.The compressive tests show that the crush load increases almost four times by increasing x from 0 to 0.2.However,the thermal conductivity and ionic conductivity are the best when x=0.05 and x=0.1,respectively.Thermal cycling stability of Li_(4)Si_(1-x)Ti_(x)O_(4) pebbles was further appraised through investigating the changes of microstructure and crush load.After undergoing thermal cycling,the Li_(4)Si_(1-x)Ti_(x)O_(4) still show higher crush load compared with Li_(4)SiO_(4),despite Ti segregation in some samples.The x=0.05 sample exhibits excellent thermal cycling stability.In summary,proper amount of Ti doping can improve the crush load,thermal and ionic conductivity,and thermal cycling stability of Li_(4)SiO_(4).
基金This research was funded by China Agricultural Research System(CARS-40)Beijing Science&Technology Committee Special Project(Z171100002217018).
文摘Colony cages for natural mating have been applied on many layer breeder farms.However,feather pecking and cloacal cannibalism are considered as prominent problems for these systems.This study aimed to investigate the effects on feather pecking and vent pecking behaviors by providing layer breeders with nest boxes(0.90 m L×0.40 m W×0.60 m H)in colony cages for natural mating(4.80 m L×1.20 m W×0.71 m H).Video recording and artificial observation were adopted.The results showed that the usage of nest boxes gradually increased from the beginning of nest boxes providing at the age of 37 weeks to the end of the experiment at the age of 55 weeks.The utilization rates of nest boxes were 36.75%,44.75%and 50.38%at the ages of 41 weeks,47 weeks and 53 weeks,respectively.The hens in the cages without nest boxes showed significantly more frequent gentle feather pecks(both given and received)than hens in the cages with nest boxes at the ages of 41 weeks,47 weeks and 53 weeks.A decreasing trend of gentle feather pecking frequency(both given and received)was found with the increasing age for both the two groups.No significant difference was found in the number of given or received severe feather pecks at the age of 41 weeks.The hens in the cages without nest boxes showed a significantly higher frequency of given and received severe feather pecks than hens in the cages with nest boxes at the ages of 47 weeks and 53 weeks(p<0.05).Both cannibalistic injury occurrence and mortality rate in the cages with nest boxes were significantly lower than those in the cages without nest boxes.In conclusion,providing nest boxes in colony cages for natural mating could decrease abnormal pecking behaviors and improve animal welfare conditions of layer breeders.
基金This study was financially supported by the Youth Innovation Promotion Association of Chinese Academy of Sciences(2018484).
文摘Nuclear fusion energy is considered as a clean and safe energy source.As the fuel of deuterium-tritium(D-T)fusion reactor,T must be produced by the reaction between neutron and lithium(Li)in the breeders.The blanket of fusion reactor will work in a high-temperature and radioactive environment.The long-term contact between T breeders and structural materials in such a harsh environment will result in corrosion and microstructure modification of material surfaces,and then affect the mechanical properties and thermal conductivity of materials.To protect the structural materials from corrosion,coatings are applied to their surface.In addition,the coating also plays a role in preventing T permeation.The compatibility of T breeder materials with structural materials and coatings in the breeding blanket has always been a concern.In this paper,the up-to-date data on liquid and solid blanket of fusion reactors,the interaction behavior of T breeders with candidate structural materials,including reduced activation ferritic/martensitic steel,oxide dispersion-strengthened steel,silicon carbide and vanadium alloy,and coatings are reviewed.The corrosion mechanism is also expounded.Furthermore,the corrosion behavior between different types of materials is compared comprehensively.At the end,the research and development prospects on this topic are suggested.
基金supported by a grant from Shandong province and a grant (200803019) from the Ministry of Agriculturesupported by a grant from Shandong province and a grant (20080019) from the Ministry of Agriculture
文摘An exogenous avian leukosis virus (ALV) strain SDAU09C1 was isolated in DF-1 cells from one of 240 imported 1-day-old white meat-type grand parent breeder chicks. Inoculation of SDAU09C1 in ALV-free chickens induced antibody reactions specific to subgroup A or B. But gp85 amino acid sequence comparisons indicated that SDAU09C1 fell into subgroup A; it had homology of 88.8%-90.3% to 6 reference strains of subgroup A, much higher compared to other subgroups including subgroup B. This is the first report for ALV of subgroup A isolated from imported breeders.
文摘Molecular markers,genome sequencing and genome editing are considered as efficient tools to accomplish demands of plant breeders for crop improvement programs.Morphological and biochemical markers have not been extensively used as these are greatly influenced by environmental factors.Different molecular markers and sequencing techniques are routinely used in evaluation of genetic diversity and evolutionary relationship,accurate classification or taxonomy,characterization of germplasm,identification of hybrids and phylogenetic studies.Desired and undesired traits controlled by genes can be identified through different molecular markers technology all over the globe.These molecular markers are well established and have successfully been used for genetic analysis of different plants during last two decades.Recently,advanced techniques of molecular markers have been developed,which provide advance genotypic platform and tends to merge valuable properties of many basic systems.New class of markers also includes little modifications in basic methods to enhance the sensitivity and resolution.Biotechnologists,plant breeders and strong investment are strongly linked for crop improvement purposes.Current review provides detailed description of different markers,genome sequencing and genome editing that have been utilized for different genetic analyses of horticultural crops.Genome editing technologies based on CRISPR/Cas are now successfully applied in horticultural crops.Moreover,current review encourages the use of molecular marker technology for DNA fingerprinting,bar coding,sequencing,re-sequencing QTL mapping,genome association mapping and genome editing.It is need of time that diverse germplasm should be identified with different molecular techniques and further utilized in breeding purposes to achieve higher yielding and resistant cultivars against biotic and abiotic stresses.
文摘A study was conducted to determine the effects of dietary digestible amino acids of feedstuffs and true metabolizable energy corrected for nitrogen on broiler breeder performance in 50 weeks to 64 weeks of age. 140 females and 20 males broiler breeders in 4 treatments with 5 replicates (7 females with a male) were used in the form of a completely randomized trial design 2 ~ 2 factorial. Four experimental diets were formulation based on two factors, first factor was included, two types of Apparent and True Metabolizable Energy corrected for Nitrogen (AMEn and TMEn) and the second factor was included, two types of Total Amino Acids (TAA) and Digestible (DAA) of feedstuffs. The result showed that egg weight, egg production (%) and egg mass (g/hen/day) was significantly different which was affected by diets formulation based on energy and interaction between energy and amino acids (P 〈 0.01). Treatment 2 (AMEn + DAA) was at the highest level significantly different (P 〈 0.01) in egg weight 68.97 g, egg production 62.45%, and egg mass 43. i g/hen/day. Hatching eggs were significantly different which was affected by diet formulation based on amino acids. Fertility, hatchability and number of chicks per hen were significant different, that were affected by diet formulation based on energy (P 〈 0.05). Interaction between two factors, were significantly different in two reproductive traits fertility and hatchability (P 〈 0.05). This experiment showed that diet formulation based on AMEn and DAA for broiler breeder was better and significant on performance.
文摘Mycoplasma synoviae (MS) is an economically important pathogenic agent of chickens, causing air sacculitis and synovitis. The diagnosis and monitoring of M. synoviae infection is usually made using serological assays, while confirmative diagnosis is made by isolation and identifcation of the organism, because of the cross reaction between M. gallisepticum and M. synoviae. This study was conducted from 2011 to 2013 during which l l broiler breeder flocks were sampled. These farms were located in all regions of morocco, The sampling was conducted as follows: Farms were visited on day one old chicks "day of importation from Europe". 20 to 60 "chicks" were randomly sampled. At the age of 8, 16, 32 and 56 weeks, 60 blood samples and 60 tracheal swabs were collected at each sampling. The serological screening was performed using Rapid Slide Agglutination (RSA) according the OIE protocol and Indirect EL1SA (IDEXX) according the manufacturer's instructions. The molecular diagnosis was performed using a commercial kit of a duplex real time PCR (Life Biotechnology). The results revealed that one day old chicks were negative to MS by RSA and PCR, however they have a variable stock of maternal antibodies (Ig-Y) detected by iELISA. The seroprevalence found by RSA is variable and increase with the age (Sth week: 55%, 16th week: 91%, 32tb and 56th week: 100%), the same profile was traced by PCR (Sth week: 36%, 16th week: 64%, 32th week: 82%, 56th week: 100%), however, all farms were positive by iELISA, from the first day to 56th weeks. These results show that MS infections are very frequent and very widespread among poultry breeder flocks, and showed a perfect agreement between serological tests and Real time PCR starting from 32th week of age.
基金supported by the Key International Cooperation Program of the National Natural Science Foundation of China (31110103916)the Agricultural Science and Technology Innovation Program, China (ASTIPIAS08)the earmaked fund for the China Agriculture Research System (CARS-42)
文摘Two experiments were conducted to investigate the effect of in ovo zinc (Zn) injection on the embryonic development, tissue Zn contents, antioxidation and related gene expressions of fertilized eggs of Arbor Acres broiler breeders. Experiment 1 was conducted to determine an optimal embryonic age for early in ovo injection. A total of 720 fertilized eggs with similar weights were randomly allotted to 4 treatments with 6 replicates per treatment and 30 eggs per replicate in a completely randomized design. The eggs were injected with 0.1 mL sterilized water at 3, 6 and 9 embryonic days of incubation (E3, E6 and E9) or non-injection (the control), respectively. The results from experiment 1 showed that E3 and E6 injections increased (P〈0.05) the embryonic mortalities, and decreased (P〈0.05) hatchabilities compared to the non-injected control, but no differences (P〉0.05) between E9 injection and the non-injected control were observed in either embryonic mortality or hatchability. The findings suggest that the E9 is the optimal embryonic age for early in ovo injection. In experiment 2, a total of 672 fertilized eggs with similar weights were randomly allocated to 7 treatments with 6 replicates per treatment and 16 eggs per replicate in a completely randomized design. The eggs were injected with 0 (the negative control), 50, 100, 150, 200, or 250 μg Zn/egg as reagent grade ZnSO4.7H20 in a 0.1-mL solution, or non-injection (the positive control), respectively at E9-10. The results from the experiment 2 demonstrated that no differences (P〉0.05) among 50 and 100 μg Zn/egg groups and the negative control were observed in the embryonic mortality and hatchability, however, the injection of 200 μg Zn/egg increased (P〈0.05) the embryonic mortality, and injections of 150 and 200 μg Zn/egg decreased (P〈0.05) hatchabilities compared with the controls. The embryonic tibia Zn contents at E20 were increased (P〈0.05) by injections of 150, 200 and 250μg Zn/egg. Zinc injection did not affect (P〉0.05) malonaldehyde (MDA) contents, copper- and Zn- containing superoxide dismutase (CuZnSOD) activities and mRNA expression levels in the liver and heart of chick embryos at E15 and E20. Compared with the negative control, injections of 50, 150 and 200 μg Zn/egg up-regulated (P〈0.05) themetallothionein (MT) mRNA expression levels in the embryonic liver at E20. These results indicated that in ovo Zn injections increased Zn contents in the embryonic tibia and MT mRNA expression levels in the embryonic liver at E20, however, injections of 150-200 μg Zn/egg were harmful to the embryonic development.
基金supported by the National Special Project of China for magnetic confined nuclear fusion energy(2015GB108004)
文摘For the solid blanket concept of helium cooled ceramic breeder (HCCB) demonstration fusion power plant (DEMO), a feasible blanket structure with configuration 2×X is proposed as considering relatively low temperature limit of neutron multiplier beryllium pebbles. Based on that, preliminary design for the typical blanket module of HCCB DEMO has been carried out and verified by thermal-hydraulic analysis and structural analysis. Furthermore, the specific relationship of maximum temperature depended on the surface heating of blanket key part first wall (FW) is also analyzed.
文摘[Objective] To investigate effects of different dietary crude protein levels on reproductive performance and find out the optimal additive proportion of crude protein. [Method] A total of 45 New Yangzhou breeder roosters at 21 weeks old were sampled and divided into three groups, namely, low-protein diet group, medium-protein diet group and high-protein diet group. They were fed with diets respectively at crude protein levels of 17.23%, 13.04% and 11.32%. The sperm volume, testicular traits and levels of reproductive hormones were analyzed during the whole repro- ductive period. [Result] The sperm volume, sperm motility and sperm density of the medium-protein diet group were higher than that of the other two groups, and the sperm deformity rate of the medium-protein diet group was lowest. The rooster's testicular traits including weight, volume and testis indexes were not significantly affected by different protein levels, but the testis shrank slowly with aging ( P 〈 0.05). The levels of testosterone (T), luteinizing hormone (LH) and follicule stimulating hormone (FSH) in plasma were respectively 6.34%, 19.64% and 3.88% higher in the lowprotein diet group than in the medium-protein diet group, and these indexes were respectively 7.20%, 17.54% and 9.84% higher in the low-protein diet group than in the high-protein diet group. But all these differences were not significant. [ Conclusion] The breeder roosters fed with the diet at the crude protein level of 13.04% show better reproductive performance and economic efficiency.
文摘The aim of this work was to compare the use of local intrauterine moist heat infusion to intrauterine antibiotics infusion, for treatment of subclinical endometritis which affects reproduction and milk production. 42 repeat breeder cows were divided into 4 groups, group 1 was the untreated control (=10 cows). Group 2 (=10 cows) was treated by 50 ml of Oxytetracycline 5% intrauterine for three successive weeks. Group 3 (=10 cows) intrauterine infusion with 30 ml saline adding to them 10 ml Gentamycin 10% and 10 ml penicillin and streptomycin for three successive weeks. Group 4 (=12 cows) intrauterine infusion with 50 ml sterile boiling water (≈100°C) was applied directly to the uterus for only one time. Leukogram was done before and after treatment, it showed leukocytosis and neutrophilia in all the study groups. After treatment for 36 hours and one week, there were no significant changes in the leukogram results of groups 1, 2 and 3. While in Group 4 showed decreasing in numbers of leukocytes (11.92 ± 0.75) and neutrophils (0.87 ± 0.16) to its normal limits after 36 hours and one-week post-treatment. Our new method gave the highest cumulative pregnancy rate 83.3% while other groups using antibiotics or antibiotics with saline gave lower pregnancy rate 40% and 50% respectively (P > 0.001). We named this new treatment method “Samia-treat;SAT”. SAT is a whole new and effective treatment for cases of repeat breeder which are caused by SCE in dairy cows;it caused increase in reproductive performance and cumulative pregnancy rate without over use of antibiotics.
文摘The objective of this study is to presume cesium corrosion process and its dominant factors in SUS316 steel, a fuel cladding material for fast breeder reactor application, based on both experimental results of cesium corrosion out-pile test and thermodynamic consideration. The cesium corrosion test was performed in simulated environment of high burn-up fuel pin. And main corrosion products in the specimen after the corrosion test were specified by TEM (transition electron microscopy) and SEM (scanning electron microscopy) in order to formulate a hypothesis of the cesium corrosion process. At the end of this study, it was found that the dominant factors of the corrosion process are the amount of cesium on the surface of the specimen, chromium content in the alloy, the supply rate of oxygen and temperature.
文摘India,under its breeding blanket R&D program for DEMO,is focusing on the development of two tritium breeding blanket concepts;namely the lead-lithium-cooled ceramic breeder and the helium-cooled ceramic breeder(HCCB).The study presented in this paper focuses on the neutronic design analysis and optimization from the tritium breeding perspective of the HCCB blanket.The Indian concept has an edge-on configuration and is one of the variants of the helium-cooled solid breeder blanket concepts proposed by several partner countries in ITER.The Indian HCCB blanket having lithium titanate(Li2TiO3)as the tritium breeder and beryllium(Be)as the neutron multiplier with reduced-activation ferritic/martensitic steel structure aims at utilizing the low-energy neutrons at the rear part of the blanket.The aim of the optimization study is to minimize the radial blanket thickness while ensuring tritium self-sufficiency and provide data for further neutronic design and thermal-hydraulic layout of the HCCB blanket.It is found that inboard and outboard blanket thicknesses of 40 cm and 60 cm,respectively,can give a tritium breeding ratio(TBR)>1.3,with 60%6Li enrichment,which is assumed to be sufficient to cover potential tritium losses and associated uncertainties.The results also demonstrated that the Be packing fraction(PF)has a more profound impact on the TBR as compared to 6Li enrichment and the PF of Li2TiO3.