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991.
German AJ Holden SL Mason SL Bryner C Bouldoires C Morris PJ Deboise M Biourge V 《Journal of animal physiology and animal nutrition》2011,95(3):368-373
Many pet cats and dogs are fed dry extruded kibbled food by measuring cup, yet the precision and accuracy of this feeding strategy is not known. Over 12 studies, we assessed precision and accuracy of weighing out food portions, of various dry kibbled foods, by measuring cup. Poor precision was noted in all studies, with intra- and inter-subject coefficients of variation ranging from 2 to 13% and 2 to 28% respectively. Variable accuracy was also noted, which ranged from an 18% under-estimate to an 80% over-estimate in portion size. No specific factors were associated with imprecision, but the degree of inaccuracy was negatively associated with portion size (R = -0.67, p = 0.022), and positively associated with the number of subjects participating in the study (R = 0.60, p = 0.048). This is the first study to document imprecision and inaccuracy of using measuring cups to estimate portions of extruded dry kibbled food. Over time, such errors could contribute to insidious weight gain in companion animals, potentially contributing to the development of obesity. Imprecision in measuring food portions could also contribute to failure of weight management programmes for obese animals. 相似文献
992.
Ragaller V Lebzien P Bigalke W Südekum KH Hüther L Flachowsky G 《Journal of animal physiology and animal nutrition》2011,95(6):730-743
To investigate the effects of a dietary pantothenic acid (PA) supplementation on duodenal nutrient flows, blood and milk variables and especially on duodenal PA flows and PA concentrations in blood and milk German Holstein cows, equipped with cannulas in the dorsal sac of the rumen and in the proximal duodenum were used. In the first experiment of the study two dry and six lactating cows received a diet with a forage to concentrate (F:C) ratio of 34:66 (high concentrate, HC), whereas in the second experiment a diet with a F:C ratio of 66:34 (high forage, HF) was fed to four dry and five lactating cows. The cows received both rations with or without 1 g PA/day. By supplementing PA to the HC ration, the molar percentage of acetic acid increased, whereas the concentration of total short chain fatty acids, the efficiency of microbial protein synthesis in the rumen and the serum glucose levels, decreased. With the HF ration the PA decreased the molar percentage of propionic acid and increased the amount of ruminally fermented organic matter. Furthermore, PA supplementation only increased the duodenal PA flow with the HF ration, while the serum and milk PA concentrations and milk PA yields were not affected. Based on the results of the present study, a rumen-unprotected supplementation of PA makes no sense. 相似文献
993.
Meganck V Govaere J Vanholder T Vercauteren G Chiers K de Kruif A Opsomer G 《Reproduction in domestic animals》2011,46(4):746-749
This paper describes two atypical cases of granulosa cell tumours (GCTs) in Belgian Blue heifers. In the first case, an 18-month-old heifer died after ovariectomy, and a granulosa-theca cell tumour was diagnosed post-mortem. The second heifer (31 months of age) was near term and was successfully treated surgically for a malignant granulosa cell tumour. Unfortunately, no further reproductive data are available, as the heifer was sold for slaughter. This is the first report describing GCTs in Belgian Blue beef cattle. 相似文献
994.
995.
Grieco V Banco B Ferrari A Rota A Faustini M Veronesi MC 《Reproduction in domestic animals》2011,46(5):920-923
Formalin-fixed, paraffin-embedded sections from 32 canine pairs of testes were immunohistochemically examined for Inhibin-α (INHα). Samples were subdivided into two groups (group 1, neonates; group 2, puppies and adults) and results statistically compared. Inhibin-α was significantly expressed only in Sertoli cells of neonatal testes, while in Leydig cells it was expressed without significant difference between groups. These results suggest that, in dogs, INHα expression switches from Sertoli to Leydig cells during testicular maturation and that, in adult, Leydig cells represent the main source of INHα. 相似文献
996.
Sattar A Rubessa M Di Francesco S Longobardi V Di Palo R Zicarelli L Campanile G Gasparrini B 《Reproduction in domestic animals》2011,46(6):1090-1097
The objectives of this work were to evaluate whether the sperm penetration speed is correlated to the in vitro fertility and whether adapting the gamete co-incubation length to the kinetics of the bull improves in vitro fertility and affects the sex ratio. In vitro matured oocytes were co-incubated with spermatozoa from four different bulls (A-D). At various post-insemination (p.i.) times (4, 8, 12, 16 and 20 h), samples of oocytes were fixed and stained with DAPI for nuclei examination, while the remaining ones were transferred into culture to evaluate embryo development. The blastocysts produced were sexed by PCR. Two bulls (A and B) had faster kinetics than the others (C and D), as shown by the higher penetration rates recorded at 4 h p.i. (43%, 30%, 11% and 6%, respectively for bulls A, B, C and D; p<0.01). The differences in the kinetics among bulls did not reflect their in vitro fertility. The incidence of polyspermy was higher for faster penetrating bulls (36%, 24%, 16% and 4%, respectively for bulls A, B, C and D; p<0.01) and at longer co-incubation times (0%, 16%, 19%, 30% and 34%, respectively at 4, 8, 12, 16 and 20 h p.i.; p<0.01). The fertilizing ability of individual bulls may be improved by adapting the co-incubation length to their penetration speed. A sperm-oocyte co-incubation length of 8 h ensured the greatest blastocyst yields for the two faster penetrating bulls. On the contrary, 16 h co-incubation was required to increase (p<0.01) cleavage rate of the two slower bulls. Bulls with a faster kinetics did not alter the embryo sex ratio towards males. The female/male (F/M) ratios recorded were 2.1, 1.4, 1.2, 1.3 and 1.6, respectively at 4, 8, 12, 16 and 20 h p.i. 相似文献
997.
Rosén LA Östman EM Shewry PR Ward JL Andersson AA Piironen V Lampi AM Rakszegi M Bedö Z Björck IM 《Journal of agricultural and food chemistry》2011,59(22):12139-12148
Rye products typically induce low insulin responses and appear to facilitate glucose regulation. The objective of this study was to investigate differences in postprandial glucose, insulin, and satiety responses between breads made from five rye varieties. Breads made from whole grain rye (Amilo, Rekrut, Dankowski Zlote, Nikita, and Haute Loire Pop) or a white wheat bread (WWB) were tested in a randomized cross-over design in 14 healthy subjects (50 g available starch). Metabolic responses were also related to the composition of dietary fiber and bioactive compounds in the breads and to the rate of in vitro starch hydrolysis. The Amilo and Rekrut rye breads induced significantly lower insulin indices (II) than WWB. Low early postprandial glucose and insulin responses (tAUC 0-60 min) were related to higher amounts of caffeic, ferulic, sinapic, and vanillic acids in the rye breads, indicating that the phenolic acids in rye may influence glycemic regulation. All rye breads induced significantly higher subjective feelings of fullness compared to WWB. A low II was related to a higher feeling of fullness and a lower desire to eat in the late postprandial phase (180 min). The data indicate that some rye varieties may be more insulin-saving than others, possibly due to differences in dietary fiber, rate of starch hydrolysis, and bioactive components such as phenolic acids. 相似文献
998.
Gonçalves R Mateus N De Freitas V 《Journal of agricultural and food chemistry》2011,59(21):11794-11802
The biological properties of procyanidins, in particular their inhibition of digestive enzymes, have received much attention in the past few years. Dietary carbohydrates are an environmental factor that is known to affect the interaction of procyanidins with proteins. This work aimed at understanding the effect of ionic food carbohydrates (polygalacturonic acid, arabic gum, pectin, and xanthan gum) on the interaction between procyanidins and trypsin. Physical-chemical techniques such as saturation transfer difference-NMR (STD-NMR) spectroscopy, fluorescence quenching, and nephelometry were used to evaluate the interaction process. Using STD-NMR, it was possible to identify the binding of procyanidin B3 to trypsin. The tested carbohydrates prevented the association of procyanidin B3 and trypsin by a competition mechanism in which the ionic character of carbohydrates and their ability to encapsulate procyanidins seem crucial leading to a reduction in STD signal and light scattering and to a recovery of the proteins intrinsic fluorescence. On the basis of these results, it was possible to grade the carbohydrates in their aggregation inhibition ability: XG > PA > AG ? PC. These effects may be relevant since the coingestion of procyanidins and ionic carbohydrates are frequent and furthermore since these might negatively affect the antinutritional properties ascribed to procyanidins in the past. 相似文献
999.
Stefanov I Baeten V Abbas O Colman E Vlaeminck B De Baets B Fievez V 《Journal of agricultural and food chemistry》2011,59(24):12771-12783
The feasibility of Raman spectroscopy in combination with partial least-squares (PLS) regression for the determination of individual or grouped trans-monounsaturated fatty acids (trans-MUFA) and conjugated linoleic acids (CLA) in milk fat is demonstrated using spectra obtained at two temperature conditions: room temperature and after freezing at -80 °C. The PLS results displayed capability for direct semiroutine quantification of several individual CLA (cis-9,trans-11 and trans-10,cis-12 C18:2) and trans-MUFA (trans-4-15 C18:1) in minor concentrations (below 1.0 g/100 g of milk fat). Calibration models were based on reference data cross-correlation or determined by specific scattering signals in the Raman spectra. Distinct bands for trans-MUFA (1674 cm(-1)) and CLA (1653 cm(-1)) from the trans isolated and cis,trans conjugated C ═ C bonds were identified, as well as original evidence for the temperature effect (new bands, peak shifts, and higher intensities) on the Raman spectra of fatty acid methyl ester and triacylglyceride standards, are supplied. 相似文献
1000.
Silva V Genta G Möller MN Masner M Thomson L Romero N Radi R Fernandes DC Laurindo FR Heinzen H Fierro W Denicola A 《Journal of agricultural and food chemistry》2011,59(12):6430-6437
The antioxidant capacity of propolis from the southern region of Uruguay was evaluated using in vitro as well as cellular assays. Free radical scavenging capacity was assessed by ORAC, obtaining values significantly higher than those of other natural products (8000 μmol Trolox equiv/g propolis). ORAC values correlated well with total polyphenol content (determined by Folin-Ciocalteu method) and UV absorption. Total polyphenol content (150 mg gallic acid equiv/g propolis) and flavonoids (45 mg quercetin equiv/g propolis) were similar to values reported for southern Brazilian (group 3) and Argentinean propolis. Flavonoid composition determined by RP-HPLC indicates a strong poplar-tree origin. Samples high in polyphenols efficiently inhibit low-density lipoprotein lipoperoxidation and tyrosine nitration. In addition, Uruguayan propolis was found to induce the expression of endothelial nitric oxide synthase and inhibit endothelial NADPH oxidase, suggesting a potential cardiovascular benefit by increasing nitric oxide bioavailability in the endothelium. 相似文献