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91.
92.
KATE ALEXANDER MARILYN DUNN ERIC NORMAN CARMEL JEAN‐PIERRE LAVOIE JÉRÔME R. E. DEL CASTILLO 《Veterinary radiology & ultrasound》2010,51(4):421-427
Glomerular filtration rate (GFR), an important parameter of renal function, is difficult to assess clinically. Serum creatinine and blood urea nitrogen measurements lack sensitivity, whereas radionuclide determination of GFR is not always available and requires postinjection patient isolation. GFR can be determined using computed tomography (CT), most commonly via Patlak plot analysis. Four adult cats, two adult dogs, and a foal underwent abdominal CT under general anesthesia for various diseases of the upper urinary tract. CT‐GFR was measured with a single‐slice dynamic acquisition and Patlak plot analysis. In five animals, the total CT‐GFR appeared to be below normal, corresponding with mild (two animals) and moderate (two animals) increases of serum creatinine in four. In the two animals with normal or increased CT‐GFR, serum creatinine was within the reference values. A significant negative logarithmic relationship was found between CT‐GFR and serum creatinine values (P=0.008; r2=0.75). No complications occurred during or following CT‐GFR. CT examination provided clinically relevant information in 3/5 patients with possible ureteral obstruction and in 3/3 patients with suspected ureteral calculi. Single‐slice dynamic CT‐GFR was practical and provided clinically useful information in this small series of patients undergoing CT of the upper urinary tract. There was a significant relationship between CT‐GFR and serum creatinine values, which supports the clinical potential of CT‐GFR and justifies further investigation of this technique. 相似文献
93.
Marina Novo Silvia Romo Manuel Rey María Jesús Prado María Victoria González 《Euphytica》2010,175(1):109-121
Fruit set in kiwifruit is strongly dependent on pollination, which is limited by the lack of efficient male pollen donors,
among other factors. We searched for molecular markers that could be polymorphic in relation to flowering time in order to
classify male kiwifruit plants to discard those that are not likely to perform as efficient pollen donors. Random amplified
polymorphic DNA (RAPD) and modified amplified fragment length polymorphism (AFLP) markers were generated using 41 male kiwifruit
plants in two flowering groups, early- and late-flowering males (with respect to the female cultivar ‘Hayward’). One RAPD
and nine modified-AFLP markers polymorphic between male plants exhibiting different flowering time were identified, sequenced
and analysed in databases. Unweighted pair group method with arithmetic average (UPGMA) clustering and multidimensional scaling
showed that these markers could be used to classify the male plants into flowering groups. Analysis of molecular variance
(AMOVA) agreed with this classification, showing that most of the genetic variation is found between flowering groups. Sequence
analysis based on a database search revealed that the polymorphism PolM contains a 7-nucleotide long element involved in the
repression of the phytochrome A gene, that Pol4 is a partial sequence of a phytochrome B gene, and that sequences Pol3, Pol5,
Pol7, and Pol9 show high identity with ESTs from kiwifruit buds treated with hydrogen cyanamide. Clustering analysis supported
the previous classification of males into flowering groups, making it feasible to predict male plants’ flowering times with
respect to the cultivar ‘Hayward’ based upon these molecular markers. 相似文献
94.
Adriano Carvalho Costa Hortência Aparecida Botelho Richardson Cesar da Silva Gomes Sergio Augusto de Sousa Campos Rafael Vilhena Reis Neto Marcio Balestre Fernanda Dotti do Prado Diogo Teruo Hashimoto Diego Galetti Martins Fbio Porto‐Foresti Mrio Lima Rilke Tadeu Fonseca de Freitas 《Aquaculture Research》2019,50(3):717-724
This work was carried out to predict the combining abilities, both general and specific, for performance traits and bodily yields of Serrasalmidae. Ninety‐six 30‐day‐old juveniles were purchased from two commercial fish farms, 12 of each of the following eight genetic groups: pacu, pirapitinga, tambaqui, tambacu, tambatinga, patinga, paqui and piraqui. Six fish from each genetic group were grown in 500‐L fibreglass tanks (two tanks per genetic group) until they were 495 days old. At the end of the growth period fish were weighed, subjected to morphometric analysis and processed to obtain their bodily yields. Two nuclear markers and one mitochondrial marker were used to confirm the identity of the animals. Combining abilities were obtained using the method proposed by Griffing in 1956 (Australian Journal of Biological Science, 4, 463–493) adapted to a mixed models analysis, environmental effects were estimated by the empirical best linear unbiased estimator method and genetic effects (general and specific combining abilities) were estimated with the empirical best linear unbiased predictor. Predictions of the combining abilities of advanced hybrids were obtained by the mixed models mixture method with normal distributions. Tambaqui showed higher general and specific combining abilities than the other groups for most of the variables, making it the most important genetic group. General combining ability makes a greater contribution to phenotypic variance than specific combining ability for most variables, indicating a predominance of genes with an additive effect in the control of evaluated traits. 相似文献
95.
Cesar Sary Fabiana Carbonera Michele Cristina da Silva Marina Oliveira Vanessa Lewandowski Humberto Todesco Jesuí Vergílio Visentainer Ivanor Nunes do Prado Ricardo Pereira Ribeiro 《Aquaculture Research》2019,50(2):673-679
This study evaluated the addition (0.35 and 0.70 g/kg feed) of clove (EOcl) or cinnamon (EOci) essential oils to Nile tilapia feed for 45 days to assess animal performance, antioxidant capacity and lipid oxidation in fillets. The design was completely randomised with five treatments and three replicates. Antioxidant capacity was determined by the oxygen radical absorbance capacity (ORACFL), 2,2‐diphenyl‐1‐picrylhydrazylhydrate (DPPH), ferric reducing ability power (FRAP) and 2,2’‐azino‐bis (3‐ethylbenzothiazoline‐6‐sulphonic acid) (ABTS) assays, and lipid oxidation was determined by the thiobarbituric acid‐reactive substances (TBARs) assay. Animal performance was not altered by adding the essential oils. The fillets treated with 0.35 g/kg of EOcl presented higher antioxidant capacity in the L‐ORACFL assay and a 40.3% reduction in lipid oxidation, whereas the EOci provided a pro‐oxidant effect relative to the control treatment. Based on these results, adding 0.35 g/kg of EOcl to the diet for 45 days before slaughter increased the antioxidant capacity and reduced the lipid oxidation of the fillets, contributing to product quality without altering animal performance. 相似文献
96.
97.
Control of nematode parasites with reduced reliance on the use of anthelmintics was studied in 16 ewes with suckling twin lambs on contaminated pasture in Denmark. Ewes and lambs were treated with albendazole at turn-out 3 May. Ewes were removed from the groups on 26 July, and lambs were slaughtered on 11 October. The animals were allocated to 4 groups of 8 lambs and their 4 ewes. Group TS was treated with albendazole at weeks 3, 6 and 8 after turnout and set-stocked; group TM was similarly treated but moved to clean pasture in conjunction with the last drenching; group US was untreated and set-stocked, and group UM was left untreated but moved to clean pasture week 8 after turn-out. Supplementary feed was offered in June and August due to scarcity of pasture. Strategic treatments of ewes and lambs weeks 3, 6 and 8 after turn-out, with or without a move to clean pasture, were highly effective in controlling nematode infections for most of the season. This was reflected in better weight gains and carcass characteristics in the treated compared to untreated lambs, resulting in an average increase in the value of the product by 36%. The effect of moving without treatment (UM) on faecal egg counts was limited but peak pasture infectivity was reduced to less than 10% compared to the set-stocked group and weight gains of lambs were significantly better despite poor feed availability in late season. The study showed that under set-stocked conditions repeated anthelmintic treatments of both ewes and lambs in early season may ensure sufficient nematode control whereas moving animals to clean pasture without dosing was less efficient. The latter may, however, still be a viable option in organic and other production systems where routine use of anthelmintics is banned, particularly if weaning and moving are combined or a second move is performed. 相似文献
98.
J. A. González M. Bruno M. Valoy F. E. Prado 《Journal of Agronomy and Crop Science》2011,197(2):81-93
Genotypic variations in leaf gas exchange and grain yield were analysed in 10 highland‐adapted quinoa cultivars grown in the field under drought conditions. Trials took place in an arid mountain region of the Northwest of Argentina (Encalilla, Amaicha del Valle, 22°31′S, 65°59′W). Significant changes in leaf gas exchange and grain yield among cultivars were observed. Our data demonstrate that leaf stomatal conductance to water vapour (gs) is a major determinant of net CO2 assimilation (An) because quinoa cultivars with inherently higher gs were capable of keeping higher photosynthesis rate. Aboveground dry mass and grain yield significantly varied among cultivars. Significant variations also occurred in chlorophyll, N and P content, photosynthetic nitrogen‐use efficiency (PNUE), specific leaf area (SLA), intrinsic water‐use efficiency (iWUE) and carboxylation capacity (An/Ci). Many cultivars gave promissory grain yields with values higher than 2000 kg ha?1, reaching for Sayaña cultivar 3855 kg ha?1. Overall, these data indicate that cultivars, which showed higher photosynthesis and conductances, were also generally more productive. Carbon isotope discrimination (Δ) was positively correlated with the grain yield and negatively with iWUE, but δ15N did not show significant correlations. This study provides a reliable measure of specific responses of quinoa cultivars to drought and it may be valuable in breeding programmes. 相似文献
99.
E van Engelen VNA Breeveld-Dwarkasing ME Everts GC van der Weyden MAM Taverne VPMG Rutten 《Reproduction in domestic animals》2009,44(2):303-311
The bovine cervix contains a large amount of smooth muscle cells distributed over an outer muscular layer and within a stromal layer. The stromal layer exhibits no electromyographic (EMG) activity at parturition. This leads to the question whether the stromal smooth muscle cells of the bovine cervix are prepared to contract with parturition, or whether they have another function. To this end, cervical biopsies were repeatedly taken from 10 pregnant cows at day-185 and -275 of gestation, at spontaneous, uncomplicated calving and at 30 days after calving. The smooth muscle bundles of the stroma were immunohistochemically analysed (n = 5) with regard to their integrity and cellular density, and the degree of staining for connexin-43, smooth muscle actin α (SMA), desmin and vimentin. Additionally, the mRNA expression for connexin-43, SMA, desmin and vimentin was determined with RT-PCR (n = 5). The smooth muscle tissue was arranged in bundles, also at parturition. However, the cellular density of these bundles and the SMA mRNA expression were decreased at parturition. Additionally, the SMA staining and connexin-43 expression and staining remained constant during pregnancy and at parturition. This might indicate that stromal smooth muscle cells are not prepared to contract with parturition, in contrast to the myometrial smooth muscle cells. The smooth muscle cells, stained for SMA, also expressed vimentin, and the proportion of co-expression was increased at day-275 of pregnancy. This suggests that the stromal smooth muscle cells predominantly have a secretory function in cows. 相似文献
100.
E van Engelen MW de Groot VNA Breeveld-Dwarkasing ME Everts GC van der Weyden MAM Taverne VPMG Rutten 《Reproduction in domestic animals》2009,44(5):834-841
The final stages of cervical ripening and parturition resemble an inflammatory process. Although the role of cytokines in both spontaneous and experimentally induced parturitions has been described in several small laboratory animals and humans, the involvement of pro‐inflammatory and regulatory cytokines in physiologic parturition in cows has not been determined. In this study, the cytokine expression profiles were assessed in bovine cervical tissue at several stages of pregnancy and at parturition. Serial biopsy samples of the cervix were obtained from 10 cows on day 185 and day 275 of pregnancy (which was on average 5.4 days before parturition) and at parturition. Messenger RNA expression levels of interleukin (IL)‐1β, IL‐6, IL‐8, IL‐10 and tumour necrosis factor (TNF)α were determined using real‐time polymerase chain reaction and the number of neutrophils and eosinophils was estimated by Luna and Sirius Red staining. At parturition, IL‐8 expression had increased 430‐fold (p < 0.001) when compared with that of the day 185 of pregnancy, large numbers of neutrophils had invaded the cervix while eosinophils remained scarce, IL‐1β had increased eightfold (p < 0.05) and IL‐6 had not changed significantly. Additionally, IL‐10 was increased by 10‐fold (p < 0.001) and TNFα decreased by 57% (p < 0.05) when compared with that of the day 185 of pregnancy. The large increase in expression of IL‐8, enabling the influx of neutrophils, is indicative of its important role in the final stage of cervical ripening and at parturition. As previous studies have shown that neutrophils excrete matrix metalloproteinases (MMP), this might contribute to softening of the cervix. In contrast, the only slightly increased levels of IL‐1, steady concentrations of IL‐6 and decreased TNFα, the potential consequences of increased IL‐10 expression, indicate that final cervical of cows in ripening at term parturition is an inflammatory process influenced by regulatory cytokines. 相似文献