Abstract-Nuclear factor-B (NF-B) regulates many genes involved in vascular physiopathology. We have previously observed in vivo NF-B activation in injured vessels that diminished by angiotensin-converting enzyme inhibition. In the present work, we investigated the effect of angiotensin II (Ang II) on NF-B activity in rat vascular smooth muscle cells, evaluating the molecular mechanisms and the specific receptor subtype involved. Ang II increased NF-B DNA binding (5-fold, 10 Ϫ9 mol/L at 1 hour; electrophoretic mobility shift assay), nuclear translocation of p50/p65 subunits, and cytosolic inhibitor B␣ (IB␣) degradation. Ang II elicited NF-B-mediated transcription (transfection of a reporter gene) and expression of NF-B-related genes (monocyte chemoattractant protein-1 and angiotensinogen). AT 1 (DUP753) and AT 2 (PD123319 and CGP42112) receptor antagonists inhibited Ang II-induced NF-B DNA binding in a dose-dependent manner (Ϸ85% for each one; 10 Ϫ5 mol/L at 1 hour). The AT 2 agonist p-aminophenylalanine 6 -Ang II augmented NF-B binding (4.6-fold, 10 Ϫ9 mol/L at 1 hour), p65 nuclear levels, and transcription of an NF-B reporter gene. AT 1 antagonist markedly inhibited NF-B-mediated transcription and gene expression. Some differences between AT 1 /AT 2 intracellular signals were found. Antioxidants and ceramide inhibitors, but not protein kinase C inhibitors, diminished NF-B activation elicited by both Ang II and the AT 2 agonist, while tyrosine kinase inhibitors only decreased Ang II-induced NF-B activity. Our results demonstrate that Ang II activates NF-B via AT 1 and AT 2 , although NF-B-mediated transcription occurred mainly through AT 1 . Both receptors share some signaling pathways (oxygen radicals and ceramide); however, tyrosine kinases only participate in AT 1 /NF-B responses. These data provide novel insights into Ang II actions, suggesting a potential implication of the AT 2 in the pathobiology of vascular cells.
A total of 3,050 German Angus (Aberdeen Angus x German dual-purpose breeds), Charolais, Hereford, Limousin, and German Simmental calves were used to examine temperament traits of beef cattle using 2 different test procedures. The chute test and the flight-speed test have been validated in terms of routine on-farm applicability. Behavior tests were performed in 2006 and 2007 on 24 commercial beef cattle farms located in the northern and eastern part of Germany. A single, trained observer assigned subjective scores to characterize the behavior of each animal during restraint in the head gate (calm, restless shifting, squirming, vigorous movement, violent struggling) and when leaving the chute (walk, trot, run, jumping out of the chute). Breed was a significant source of variation in chute scores and flight-speed scores (P < 0.001). Charolais and Limousin cattle had the greatest scores in both traits, whereas Herefords had the least (P < 0.001) chute scores. German Angus and Hereford calves had the least (P < 0.001) flight-speeds, indicating that these breeds have a more favorable temperament. Temperament scores differed significantly between male and female calves (P < 0.01), with females scoring better for both traits. Average daily BW gains of the calves were significantly influenced by effects of breed (P < 0.001) and sex (P < 0.001) of the calves. Heritabilities were estimated for chute- and flight-speed scores of beef cattle. They were least for chute score and flight-speed score of Limousin cattle with values of 0.11. In contrast, greatest heritabilities were 0.33 for chute score and 0.36 for flight-speed score of Hereford cattle. Genetic correlations were estimated among both temperament traits, with values between 0.57 and 0.98. Chute scores and visual flight-speed scores were negatively correlated with daily BW gain of the calves in most breeds. The results presented in this paper indicate that on-farm evaluation of beef cattle temperament is possible, either using the chute test or the flight-speed test. Genetic selection seems to be promising to improve temperament traits of beef cattle without decreasing production traits like ADG of the calves.
The objective of this study was to compare a conventional dairy cattle breeding program characterized by a progeny testing scheme with different scenarios of genomic breeding programs. The ultimate economic evaluation criterion was discounted profit reflecting discounted returns minus discounted costs per cow in a balanced breeding goal of production and functionality. A deterministic approach mainly based on the gene flow method and selection index calculations was used to model a conventional progeny testing program and different scenarios of genomic breeding programs. As a novel idea, the modeling of the genomic breeding program accounted for the proportion of farmers waiting for daughter records of genotyped young bulls before using them for artificial insemination. Technical and biological coefficients for modeling were chosen to correspond to a German breeding organization. The conventional breeding program for 50 test bulls per year within a population of 100,000 cows served as a base scenario. Scenarios of genomic breeding programs considered the variation of costs for genotyping, selection intensity of cow sires, proportion of farmers waiting for daughter records of genotyped young bulls, and different accuracies of genomic indices for bulls and cows. Given that the accuracies of genomic indices are greater than 0.70, a distinct economic advantage was found for all scenarios of genomic breeding programs up to factor 2.59, mainly due to the reduction in generation intervals. Costs for genotyping were negligible when focusing on a population-wide perspective and considering additional costs for herdbook registration, milk recording, or keeping of bulls, especially if there is no need for yearly recalculation of effects of single nucleotide polymorphisms. Genomic breeding programs generated a higher discounted profit than a conventional progeny testing program for all scenarios where at least 20% of the inseminations were done by genotyped young bulls without daughter records. Evaluation of levels of annual genetic gain for individual traits revealed the same potential for low heritable traits (h 2 = 0.05) compared with moderate heritable traits (h 2 = 0.30), preconditioning highly accurate genomic indices of 0.90. The final economic success of genomic breeding programs strongly depends on the complete abdication of any forms of progeny testing to reduce costs and generation intervals, but such a strategy implies the willingness of the participating milk producers.
Somatic cell counts (SCC) are generally used as an indicator of udder health. Currently in Germany, 100,000 cells/mL is the threshold differentiating infected and noninfected mammary glands. The aim of our study was the detailed analysis of udder health in a representative part of the dairy cow population in Hesse, Germany. Between 2000 and 2008, 615,187 quarter foremilk samples were analyzed. In addition to evaluation of distribution of SCC and prevalence of mastitis pathogens, pathogen prevalence was also calculated depending on SCC. The data indicated that 38% of all samples had SCC >100,000 cells/mL and 62% showed SCC ≤ 100,000 cells/mL; 31% of all samples revealed SCC ≤ 25,000 cells/mL. Coagulase-negative staphylococci were the dominant pathogens in the Hessian quarter foremilk samples (17.17% of all samples) followed by Corynebacterium spp. (13.56%), Streptococcus uberis (8.7%), and Staphylococcus aureus (5.01%). Mastitis pathogens were detected in 83% of all samples with SCC >100,000 cells/mL. However, the prevalence of mastitis pathogens in the SCC range from 1,000 to ≤ 100,000 cells/mL was 8.5% (5.51% minor pathogens, 2.01% major pathogens, and 0.98% other pathogens). For farms producing high quality milk, exceptional hygiene management is compulsory. One of the farms randomly selected showed clearly different results from the Hessian survey. Fifteen percent more samples lay in the SCC range ≤ 100,000 cells/mL with a lower prevalence of mastitis pathogens of 1.91% (1.03% minor pathogens, 0.83% major pathogens, and 0.05% other pathogens). Based on these results, inflammatory processes can obviously be detected in mammary glands of udder quarters healthy according to the current definitions. However, we argue that such inflammation can be detected by examination of the relationship of immune cells in milk.
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