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11.
A polymorphic site of the growth hormone gene (AluI polymorphism) that results in an amino acid change at position 127 of the protein chain (leucine, L to valine, V) has been linked to differences in circulating metabolites and metabolic hormones of calves and bulls and to milk yield traits of lactating cows. Our objective was to investigate the interrelationship of this polymorphism with plasma concentrations of β-hydroxybutyrate, insulin, IGF-I and leptin in postpartum dairy cows. Blood samples were taken from clinically healthy, spring-calving, group-fed Holstein-Friesian cows (n = 257; 7 large-scale farms) 4–13 days after calving. Of all herds, 100 cows had plasma β-hydroxybutyrate levels above 1.2 mmol/l and 157 cows were normoketonemic. The proportion of valine carriers and LL cows was not different within groups of normo- and hyperketonemic animals. Genotype was not associated with plasma β-hydroxybutyrate, insulin, IGF-I and leptin levels either in all of the herds or in the two with the highest proportion of the valine allele carriers (n = 28, 72%). We found significantly lower insulin, IGF-I and leptin concentrations in the presence of hyperketonemia compared to normoketonemic cows. There were strong negative correlations between BHB and the other blood parameters, while insulin, IGF-I and leptin were positively related to each other. In conclusion, in the first two weeks after calving we could not demonstrate any effect of AluI polymorphism on plasma concentrations of β-hydroxybutyrate and metabolic hormones studied. Hyperketonemia was associated with a significant decrease in insulin, IGF-I and leptin blood levels. We infer that cows homozygous for the leucine allele or carrying the valine allele may have a similar endocrine and metabolic response to the challenge of increased nutrient demand early postpartum and that the presence of hyperketonemia is mainly linked to the hormonal and metabolic changes occurring at the onset of lactation.  相似文献   
12.
The quantity of available wheat gluten exceeds the current food use markets. Thermoforming is an alternative technical means for transforming wheat gluten. Thermoforming was applied here to wheat gluten under chemically reductive conditions to form pliable, translucent sheets. A wide variety of conditions, i.e., temperature, reducing agents, plasticizers and additives were tested to obtain a range of elastic properties in the thermoformed sheets. These properties were compared to those of commercially available polymers, such as polypropylene. Elasticity of the gluten formulations were indexed by Young's modulus and were in the range measured for commercial products when tested in the 30-70% relative humidity range. Removal of the gliadin subfraction of gluten yielded polymers with higher Young's modulus since this component acts as a polymer-chain terminator. At relative humidity less than 30% all whole gluten-based sheets were brittle, while above 70% they were highly elastic.  相似文献   
13.
Porcine circoviruses (PCV) are widespread in domestic pigs worldwide and there is growing information about the presence of PCV in other suid species. Based on serological studies with sera of wild boars, it was established that PCV1 was present in these animals and antibodies specific to PCV2 were also detected in wild boars living in captivity or in sylvatic areas, both with or without clinical signs of PMWS. Studies including PCV2 genome or antigen detection confirmed the previous findings. This is the first report about the presence of PCV in Transylvanian wild boar populations. Four hundred and sixty-nine samples were collected and grouped according to geographic origin, tested for the presence of PCV DNA using a real-time quantitative polymerase chain reaction assay, and 13.52% of the animals proved to be positive for one or in three cases both of the PCV genotypes. PCV2 was detected in all of the PCV-positive samples.  相似文献   
14.
Various antioxidant assays are used to characterize fruits consumed fresh or processed although an easy, reliable and cheap assay is not available to follow the changes in antioxidant power. This study tested the applicability of a recently developed antioxidant measuring system, Water-soluble (ACW) and Lipid-soluble (ACL) Antioxidant Capacity, using the PHOTOCHEM® instrument. Initially, 13 cultivars of 4 berry species were assayed with Photochem and compared with widely used methods based on single electron transfer reactions like ferric reducing ability of plasma, total polyphenolic content (TPC) and 2,2′-diphenyl-1-picrylhydrazyl radical-scavenging capacity. Assays based on hydrogen atom transfer reactions were also carried out including total radical-scavenger capacity (TRSC). The correlations among the results were all significant at P ≤ 0.05, except the one between TPC and ACW. The overall antioxidant capacity ranked on the order of strawberry < red currant < raspberry < black currant. However, significant differences could have been detected among genotypes and antioxidants assays used for the analysis. The Photochem instrument is not suitable for easy, cheap and high-throughput routine analysis of berry antioxidant capacity and hence is not preferable to other assays.  相似文献   
15.
Pot experiments were conducted in order to evaluate the effects of four different urea or ammonium containing polyolefin‐coated fertilizers (POCFs) on the nutritional quality of spinach (Spinacia olèracea L.) and to investigate the mechanisms of these effects in comparison with conventional, rapidly available fertilizer. Compared to the conventional fertilization method yield was decreased in all the four POCF treatments due to less available fertilizer nitrogen (N) and/or realized ammonium nutrition. However, application of POCFs decreased oxalate and nitrate contents and increased ascorbate concent in spinach. Decreased oxalate and nitrate contents were attributed to lower nitrate availability in the soil having caused by the controlled‐released characteristic of POCFs and/or ammonium nutrition. Increased ascorbate content was due to both decreased oxalate and decreased nitrogen contents of the spinach plants. It was concluded that band applications of urea or ammonium containing POCFs improved the nutritional quality of spinach due to realized ammonium nutrition and/or less amount of available fertilizer N.  相似文献   
16.
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   
17.
Two F2 generations of an intercross between Hampshire boars and Hungarian Large White sows were produced to estimate the effects of the porcine KIT genotypes (II, Ii and ii) on quantitative and qualitative haematological indices, on piglet birth weight and growth performance until weaning. Piglets carrying the I allele had significantly fewer lymphocytes (p = 0.041) than the ii homozygotes, heterozygotes had measures between the two homozygotes. KIT genotypes did not influence white blood cells, red blood cells, haemoglobin and haematocrite. II genotype piglets were significantly lighter at birth than the ones carrying the recessive i allele, the effect of KIT genotypes on gain until weaning was not significant, but II piglets tended to gain less. The results of this study support the hypothesis of M. Johansson, H. Ellegren, L. Marklund, U. Gustavsson, E. Ringmar‐Cederberg, K. Andersson, I. Edfors‐Lilja and L. Andersson [(1992) Genomics, 14 , 965] that the pleiotrophic effect of the porcine KIT mutations on haematopoietic cells must be mild.  相似文献   
18.
19.
An abdominal cystic lymphangiomatosis in a Mt. Carmel blind mole rat (Nannospalax (ehrenbergi) carmeli) is described. This case was most likely due to a congenital abnormality with long-term compensation by the animal. The case describes the clinical course and subsequent postmortem examination. The death in the animal was caused by an abscess in the peritoneal wall and subsequent peritonitis.  相似文献   
20.
Mitogen activated protein (MAP) kinases are key components in signalling networks. In Fusarium graminearum, one of the most devastating fungal plant pathogens, two MAP kinases are known to be involved in pathogenicity, Mgv1 and the Gibberella pathogenicity MAP kinase Gpmk1. ??gpmk1 mutants with a disrupted GPMK1 gene are unable to infect wheat spikelets. They exhibit altered secretion of several extracellular enzymes. Among those, the lipase FGL1 is known to be a major virulence factor of F. graminearum. FGL1 gene expression was decreased in ??gpmk1 strains during wheat head infection. To uncouple FGL1 expression from Gpmk1 activity, we generated ??gpmk1 strains that constitutively express FGL1 under control of the Cochliobolus heterostrophus glyceraldehyde 3-phosphate dehydrogenase (GPD) promoter. The level of extracellular lipolytic activity of these strains in culture was comparable to the wild-type. These mutants showed fully restored conidiation and partial complementation of defects in development that were reported from the ??gpmk1 mutant. They also partially complemented the apathogenic disease phenotype of the ??gpmk1 mutants causing lesions in directly inoculated wheat spikelets. But in contrast to wild-type, their growth was restricted to directly inoculated spikelets. A barrier-like formation was observed at the rachis node. Based on these results, we could show that the lipase FGL1 is necessary but not sufficient to restore complete pathogenicity to the apathogenic ??gpmk1 mutant. Hence, we hypothesize that the MAP kinase Gpmk1 is involved in the regulation of additional factors required for complete virulence of F. graminearum.  相似文献   
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