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51.
Genetic correlations between phenotypically similar or related traits tested at young horse performance tests for Danish Warmblood (DWB) and Swedish Warmblood (SWB) horses were calculated using Multi-trait Across Country Evaluation (MACE). Data comprised stallions with an estimated breeding value (EBV) from the national genetic evaluations (NGE) based on at least 10 progeny tested in performance tests, and the ancestors of those stallions in two generations. The DWB data included 349 stallions and the SWB data 426 stallions. Of these, 28 had EBVs in both DWB and SWB. Additionally 151 pedigree animals were common between DWB and SWB. The dependent variables used were NGE results of stallions born 1980 and later, which reduced the number of common stallions with EBVs to 23. The genetic correlations were very high for jumping traits (0.99) and dressage related traits (0.89–0.97). For conformation traits correlations varied between 0.10 and 0.98. Because of the high genetic correlations and frequent use of same or closely related foreign stallions, breeders of both DWB and SWB would benefit from using the NGEs for performance traits across countries, although the genetic correlations do not consider differences in genetic merit levels between the populations. It would be feasible to perform a joint genetic evaluation using MACE, which would improve the reliability of estimated breeding values, and enable ranking of all stallions according to the national scale of each country. 相似文献
52.
Andrzej Pedryc Szabolcs Ruthner Rita Hermán Boris Krska Attila Hegedűs Júlia Halász 《Scientia Horticulturae》2009
Eight polymorphic simple sequence repeat (SSR) markers located in the G1 linkage group of apricot (Prunus armeniaca L.) were previously developed and evaluated in a small set of cultivars. Those primers were used for studying variability in 77 apricot cultivars belonging to five different geographical groups, such as Chinese, Asian (Irano-Caucasian and Central Asian), North American, Mediterranean and Western European as well as Middle European cultivars. Six of the markers were polymorphic and revealed a total of 71 alleles ranging from 5 (aprigms11) to 20 (aprigms1) alleles per locus with a mean value of 11.83 alleles per locus. In conclusion, the SSR loci located in the G1 linkage group show a level of polymorphism which is similar to loci dispersed throughout the entire genome. The total number of alleles and the number of unique alleles were the highest in Chinese apricots and the lowest in Middle European cultivars. Heterozygosity also showed a decrease from Asia and China to Middle Europe. No association could have been observed between any SSR markers tested and plum pox virus (PPV) resistant phenotype of cultivars. PPV resistant cultivars did not form a separate clade on the dendrogram obtained by UPGMA cluster analysis. Middle European and Chinese cultivars formed separate clusters while other genotypes formed smaller multiple sub-groups or scattered among different clusters. Our results support previous hypotheses on the origin of PPV resistance in North American apricots. The allele data was also presented in a form that allowed the easy observation of allele frequencies in each geographical group at each locus. Using this data field, differences and similarities between cultivar groups can be easily assessed. The analysis demonstrated the links between the North American and Mediterranean apricot germplasm and confirmed that the Chinese and Eastern European cultivars are distantly related. 相似文献
53.
Adrián J. Hernández Shuichi Satoh Viswanath Kiron 《Journal of the World Aquaculture Society》2012,43(5):688-696
This study was conducted to evaluate the effect of citric acid (CA) and amino acid chelated trace elements (AA) on the growth, phosphorus (P) utilization efficiency and loading in rainbow trout fed a diet formulated with a low‐fish meal (FM) concentration. A low‐FM basal diet with or without monocalcium phosphate supplementation served as positive and negative control correspondingly. Dietary treatments consisted of the basal diet supplemented either with 1% CA, AA (equivalent to 40 Zn, 20 Mn, and 4 Cu mg/Kg of diet instead of inorganic trace element mix) or a combination of both. Duplicate groups of 35 fish (13.2 g) were fed until apparent satiation during 12 wk. Group of fish fed diets supplemented with 1% CA or AA had a final growth and feed utilization similar to that observed in fish fed the positive control diet (P > 0.05). P absorption was increased with the addition of CA or AA. P retention efficiency rates for these diets were higher in comparison with the rest of the treatments consequently showing the lowest P loading values (P < 0.05). The results indicate that addition of 1% CA or AA, to a low‐FM diet without inorganic P supplementation enhanced fish growth, P retention, and decreased P load to the environment. 相似文献
54.
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56.
响应面法优化Xenorhabdus nematophila发酵培养基的研究 总被引:1,自引:0,他引:1
【目的】提高Xenorhabdus nematophilaYL001的抗菌活性,为该菌株杀菌活性成分的提取分离及生物农药的开发应用奠定基础。【方法】以YSG培养基为基础,采用单因子试验方法,对最佳碳源和氮源进行筛选,并采用全因子中心组合试验设计和响应面法对其最佳配比进行优化。【结果】YL001菌株的最佳碳源为玉米粉,氮源为豆饼粉,培养基的最佳组成为:玉米粉9.69 g/L,豆饼粉76.50 g/L,MgSO41.07 g/L,(NH4)2SO41.79 g/L,KH2PO40.63 g/L,K2HPO40.80 g/L,Na2SO41.25 g/L,在此条件下,YL001菌株抗菌活性达268.9 U/mL。【结论】培养基优化后YL001菌株的抗菌活性与试验的预测值接近,表明响应面法在培养基优化中十分有效,相对简单,且节省时间和材料。 相似文献
57.
Sandra Villagmez-Estrada Jos F Prez Diego Melo-Durn Francesc Gonzalez-Sol Matilde DAngelo Francisco J Prez-Cano David Sol-Oriol 《Journal of animal science》2022,100(6)
Modern hyperprolific sows must deal with large litters (16–20 piglets) which reduce piglet birthweight with a concomitant increase in the proportion of small and intrauterine growth retarded piglets. However, larger litters do not only have a greater variation of piglet weights, but also a greater variation in colostrum and milk consumption within the litter. To further understand the impact that body weight has on piglets, the present study aimed to evaluate the degree of physiological weakness of the smallest piglets at birth and during the suckling period (20 d) compared to their middle-weight littermates through their jejunal gene expression. At birth, light piglets showed a downregulation of genes related to immune response (FAXDC2, HSPB1, PPARGC1α), antioxidant enzymes (SOD2m), digestive enzymes (ANPEP, IDO1, SI), and nutrient transporter (SLC39A4) (P < 0.05) but also a tendency for a higher mRNA expression of GBP1 (inflammatory regulator) and HSD11β1 (stress hormone) genes compared to their heavier littermates (P < 0.10). Excluding HSD11β1 gene, all these intestinal gene expression differences initially observed at birth between light and middle-weight piglets were stabilized at the end of the suckling period, when others appeared. Genes involved in barrier function (CLDN1), pro-inflammatory response (CXCL2, IL6, IDO1), and stress hormone signaling (HSD11β1) over-expressed compared to their middle-weight littermates (P < 0.05). In conclusion, at birth and at the end of suckling period, light body weight piglets seem to have a compromised gene expression and therefore impaired nutrient absorption, immune and stress responses compared to their heavier littermates. 相似文献
58.
Fernández-Varón E Villamayor L Escudero E Espuny A Cárceles CM 《Veterinary journal (London, England : 1997)》2006,172(2):302-307
The pharmacokinetics of moxifloxacin was studied following intravenous (IV) and subcutaneous (SC) administration of 5 mg/kg to healthy lactating goats (n = 6). Moxifloxacin concentrations were determined by high performance liquid chromatography assay with fluorescence detection. The moxifloxacin plasma concentration versus time data after IV administration could best be described by a two compartment open model. The disposition of SC administered moxifloxacin was best described by a one-compartment model. The plasma moxifloxacin clearance (Cl) for the IV route was 0.43 +/- 0.02 L/kg (mean +/- SE). The steady-state volume of distribution (Vss) was 0.79 +/- 0.08 L/kg. The terminal half-life (t1/2lambdaz) was 1.94 +/- 0.41 and 2.98 +/- 0.48 h after IV and SC administration, respectively. The absolute bioavailability was 96.87 +/- 10.27% after SC administration. Moxifloxacin penetration from blood to milk was quick for both routes of administration and the high AUCmilk/AUCplasma and Cmax-milk/Cmax-plasma ratios reached indicated a wide penetration of moxifloxacin into the milk. From these data, it appears that a 5 mg/kg SC dose of moxifloxacin would be effective in lactating goats against bacterial isolates with MIC < or = 0.20 microg/mL in plasma and MIC < or = 0.40 microg/mL in milk. 相似文献
59.
Detection of challenge virus in fetal tissues by nested PCR as a test of the potency of a porcine parvovirus vaccine 总被引:1,自引:0,他引:1
Belák S. Rivera E. Ballagi-Pordány A. Hanzhong W. Widén F. Soós T. 《Veterinary research communications》1998,22(2):139-146
To estimate the potency of a porcine parvovirus (PPV) vaccine, three vaccinated and three non-vaccinated pregnant gilts were infected with PPV and the distribution of the virus was studied in the tissues of their 51 fetuses. Virus detection was attempted using haemagglutination (HA) and immunofluorescence (IF) assays, as well as by standard (single) and nested polymerase chain reactions (PCR). None of the detection methods yielded positive results when used to test for the presence of virus in suspensions of organs from the fetuses from the vaccinated gilts. However, the virus was detected in the fetuses from non-vaccinated gilts as follows: HA was positive in 14 cases out of 23 (60.8%), IF in 16/23 (69.5%), standard PCR in 12/20 (60%), and the nested PCR in 19/23 (82.6%). Although the correlation among the results of various methods of virus detection was rather close (r<0.83), the sensitivity of the nested PCR was the highest, both when testing dilutions of PPV and when analysing the fetal organs. The nested PCR therefore provides a reliable approach for studies of virus distribution in fetal organs, with special reference to potency tests on vaccines. 相似文献
60.
Radiographic features of the limbs of juvenile and subadult loggerhead sea turtles (Caretta caretta) 下载免费PDF全文
Ana Luisa Valente Ignasi Marco Maria Angeles Zamora Maria Luz Parga Santiago Lavín Ferran Alegre Rafaela Cuenca 《Canadian journal of veterinary research》2007,71(4):305-313
This study aimed to provide the normal radiographic anatomic appearance of the limbs of the loggerhead sea turtle, Caretta caretta. Dorsopalmar and dorsoplantar radiographs were taken of the forelimbs and hindlimbs of 15 juvenile and 15 subadult loggerhead sea turtles, 17 alive and 13 dead. For comparison, computed tomographic, gross anatomic, osteologic, and histologic studies were performed on the limbs of 5 of the sea turtles. Bones from the distal part of the fore and hind flippers were seen in detail with a mammographic film-screen combination. The pectoral and pelvic girdles, superimposed by the carapace, were better seen on standard radiographs with the use of rare-earth intensifying screens. Mammographic radiographs of the manus of 5 small juvenile turtles showed active growth zones. Visualization of bone contours in the distal part of the limbs was clearer than in mammals owing to the very few superimpositions. The presence of a substantial amount of cartilage in the epiphyses produced better visibility of limb ends. We conclude that use of a mammography film-screen combination is the best way to evaluate the bony and joint structures of the limbs of sea turtles. Radiography provides reliable images for clinical purposes. Considering the low cost and logistics of this technique, it is a practical ancillary test for marine animal rehabilitation centers to use. 相似文献