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71.
Pigs, intelligent and potentially destructive animals, can present unique challenges to laboratory animal caretakers trying to provide optimal housing and environmental enrichment. The authors developed an enrichment area in their facility for pigs that are neither preparing for nor recovering from surgery. They rotate pigs into the play area for periodic enrichment and socialization. 相似文献
72.
Ankit Magotra I. D. Gupta Archana Verma Rani Alex Vineeth MR Tavsief Ahmad 《Animal biotechnology》2019,30(1):75-81
The present study was conducted to identify polymorphisms in CACNA2D1 gene and their association with clinical mastitis and production traits. Exon 18 and its flanking regions were screened for the presence of SNPs. Statistical analysis was performed to identify association of period of birth, breed, and genotype with mastitis incidence on randomly selected 103 Sahiwal and 102 Karan Fries cattle. PCR-RFLP analysis revealed that g.38819398G?>?A mutation in exon 18 (269?bp amplicon) of CACNA2D1 gene resolved into AA, AG, and GG genotypes in Sahiwal and Karan Fries cattle. Wald chi-square analysis revealed that the period of birth, breed, and genotype were significantly associated with mastitis incidence. GG genotyped cattle were found to be less susceptible to mastitis. Least square analysis revealed that GG and AG genotype animals of G38819398A SNP of CACNA2D1 gene in Sahiwal as well as in Karan Fries cattle were associated with higher average milk yields during 1st, 2nd, and 3rd lactations (P?<?0.01). These observations and their differential association with the incidence of mastitis and production traits can be utilized as an aid to selection for simultaneous improvement of both antagonistic traits; however, validation of results on large number of animals is warranted. 相似文献
73.
Alvarez-Manilla G Warren NL Abney T Atwood J Azadi P York WS Pierce M Orlando R 《Glycobiology》2007,17(7):677-687
Analysis of oligosaccharides by mass spectrometry (MS) has enabled the investigation of the glycan repertoire of organisms with high resolution and sensitivity. It is difficult, however, to correlate the expression of glycosyltransferases with the glycan structures present in a particular cell type or tissue because the use of MS for quantitative purposes has significant limitations. For this reason, in order to develop a technique that would allow relative glycan quantification by MS analysis between two samples, a procedure was developed for the isotopic labeling of oligosaccharides with (13)C-labeled methyl iodide using standard permethylation conditions. Separate aliquots of oligosaccharides from human milk were labeled with (12)C or (13)C methyl iodide; the labeled and non-labeled glycans were mixed in known proportions, and the mixtures analyzed by MS. Results indicated that the isotopic labeling described here was capable of providing relative quantitative data with a dynamic range of at least two orders of magnitude, adequate linearity, and reproducibility with a coefficient of variation that was 13% on average. This procedure was used to analyze N-linked glycans released from various mixtures of glycoproteins, such as alpha-1 acid glycoprotein, human transferrin, and bovine fetuin, using MS techniques that included matrix assisted laser desorption ionization-time of flight MS and electrospray ionization with ion cyclotron resonance-Fourier transformation MS. The measured (12)C:(13)C ratios from mixtures of glycans permethylated with either (12)CH(3)I or (13)CH(3)I were consistent with the theoretical proportions. This technique is an effective procedure for relative quantitative glycan analysis by MS. 相似文献
74.
75.
Analytical and numerical models were developed to describe fluorescence resonance energy transfer (RET) in crowded biological membranes. It was assumed that fluorescent donors were linked to membrane proteins and that acceptors were linked to membrane lipids. No restrictions were placed on the location of the donor within the protein or the partitioning of acceptors between the two leaflets of the bilayer; however, acceptors were excluded from the area occupied by proteins. Analytical equations were derived that give the average quantum yield of a donor at low protein concentrations. Monte Carlo simulations were used to generate protein and lipid distributions that were linked numerically with RET equations to determine the average quantum yield and the distribution of donor fluorescence lifetimes at high protein concentrations, up to 50% area fraction. The Monte Carlo results show such crowding always reduces the quantum yield, probably because crowding increases acceptor concentrations near donor-bearing proteins; the magnitude of the reduction increases monotonically with protein concentration. The Monte Carlo results also show that the distribution of fluorescence lifetimes can differ markedly, even for systems possessing the same average lifetime. The dependence of energy transfer on acceptor concentration, protein radius, donor position within the protein, and the fraction of acceptors in each leaflet was also examined. The model and results are directly applicable to the analysis of RET data obtained from biological membranes; their application should result in a more complete and accurate determination of the structures of membrane components. 相似文献
76.
Rodrigo M Mota João S Luiz Moreira Marcelo R Souza M Fátima Horta Santuza MR Teixeira Elisabeth Neumann Jacques R Nicoli Álvaro C Nunes 《BMC biotechnology》2006,6(1):2-11
Background
The use of lactic acid bacteria as vehicles to delivery antigens to immunize animals is a promising issue. When genetically modified, these bacteria can induce a specific local and systemic immune response against selected pathogens. Gastric acid and bile salts tolerance, production of antagonistic substances against pathogenic microorganisms, and adhesive ability to gut epithelium are other important characteristics that make these bacteria useful for oral immunization. 相似文献77.
Willis RB Abney MR Holmes GJ Schultheis JR Kennedy GG 《Journal of economic entomology》2010,103(6):2087-2093
Three studies were conducted to determine the effect of preceding crop on wireworm (Coleoptera: Elateridae) abundance in the coastal plain of North Carolina. In all three studies, samples of wireworm populations were taken from the soil by using oat, Avena sativa L., baits. Treatments were defined by the previous year's crop and were chosen to reflect common crop rotations in the region. Across all three studies, eight wireworm species were recovered from the baits: Conoderus amplicollis (Gyllenhal), Conoderus bellus (Say), Conoderus falli (Lane), Conoderus lividus (Degeer), Conoderus scissus (Schaeffer), Conoderus vespertinus (F.), Glyphonyx bimarginatus (Schaeffer), and Melanotus communis (Gyllenhal). The effect of corn, Zea mays L.; cotton, Gossypium hirsutum L.; fallow; soybean, Clycine max (L.) Merr.; sweet potato, Ipomoea batatas (L.) Lam.; and tobacco (Nicotiana spp.) was evaluated in a small-plot replicated study. M. communis was the most frequently collected species in the small-plot study and was found in significantly higher numbers following soybean and corn. The mean total number of wireworms per bait (all species) was highest following soybean. A second study conducted in late fall and early spring assessed the abundance of overwintering wireworm populations in commercial fields planted to corn, cotton, peanut (Arachis hypogaea L.), soybean, sweet potato, and tobacco in the most recent previous growing season. C. lividus was the most abundant species, and the mean total number of wireworms was highest following corn and soybean. A survey was conducted in commercial sweet potato in late spring and early summer in fields that had been planted to corn, cotton, cucurbit (Cucurbita pepo L.), peanut, soybean, sweet potato, or tobacco in the most recent previous growing season. C. vespertinus was the most abundant species, and the mean total number of wireworms per bait was highest following corn. 相似文献
78.
Nanees F El-Malkey Amira E Alsemeh Wesam MR Ashour Nancy H Hassan Husam M Edrees 《Experimental biology and medicine (Maywood, N.J.)》2021,246(11):1307
Intestinal tissue is highly susceptible to ischemia/reperfusion injury in many hazardous health conditions. The anti-inflammatory and antioxidant glycoprotein fetuin-A showed efficacy in cerebral ischemic injury; however, its protective role against intestinal ischemia/reperfusion remains elusive. Therefore, this study investigated the protective role of fetuin-A supplementation against intestinal structural changes and dysfunction in a rat model of intestinal ischemia/reperfusion. We equally divided 72 male rats into control, sham, ischemia/reperfusion, and fetuin-A-pretreated ischemia/reperfusion (100 mg/kg/day fetuin-A intraperitoneally for three days prior to surgery and a third dose 1 h prior to the experiment) groups. After 2 h of reperfusion, the jejunum was dissected and examined for spontaneous contractility. A jejunal homogenate was used to assess inflammatory and oxidative stress enzymes. Staining of histological sections was carried out with hematoxylin, eosin and Masson’s trichrome stain for evaluation. Immunohistochemistry was performed to detect autophagy proteins beclin-1, LC3, and p62. This study found that fetuin-A significantly improved ischemia/reperfusion-induced mucosal injury by reducing the percentage of areas of collagen deposition, increasing the amplitude of spontaneous contraction, decreasing inflammation and oxidative stress, and upregulating p62 expression, which was accompanied by beclin-1 and LC3 downregulation. Our findings suggest that fetuin-A treatment can prevent ischemia/reperfusion-induced jejunal structural and functional changes by increasing antioxidant activity and regulating autophagy disturbances observed in the ischemia/reperfusion rat model. Furthermore, fetuin-A may provide a protective influence against intestinal ischemia/reperfusion complications. 相似文献
79.
M.R. Abney C.E. Sorenson F. Gould & J.R. Bradley Jr. 《Entomologia Experimentalis et Applicata》2008,126(1):46-52
Differences in the stable carbon isotope ratios of plants utilizing the C3 vs. C4 photosynthetic pathway have been used to broadly identify the natal host origins of herbivorous insects. This study explored whether adequate variation exists between the carbon isotope ratios of different C3 plants in the host range of Heliothis virescens (Fabricius) (Lepidoptera: Noctuidae) to enable accurate identification of natal host‐plant species. Isotope ratio mass spectrometry (IRMS) analysis of 13C/12C ratios of moths reared on four crop plant species [Gossypium hirsutum (L.), Nicotiana tabacum L., Glycine max (L.) Merrill, and Arachis hypogaea L.] and two common weed species [Geranium carolinianum L. and Linaria canadensis (L.) Chaz.] revealed a range of δ13C values within that expected for plants utilizing the C3 photosynthetic pathway. Analysis of vegetative and reproductive tissues from the plants utilized in the study resulted in statistically different δ13C values for some plant species; nevertheless, the range of δ13C values observed for many plant species overlapped. Significant differences in mean δ13C values were detected between groups of moths reared on different host‐plant species, but there was no significant correlation between the δ13C values of moths vs. the δ13C value of plant tissue on which they were reared. Feral tobacco budworm moths collected over 3 years were found to have carbon isotope ratios consistent with those having fed on C3 plants, confirming little utilization of C4 plant species by the insect. Results demonstrate that within the range of C3 host plants tested, carbon isotope signatures are not sufficiently unique to enable a reliable determination of natal origin of feral tobacco budworm with current IRMS technology. 相似文献
80.