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Kidneys from young fowl fed a salt deficient diet for up to five weeks were examined under the electron microscope. The presence of maculae densae (MD) were confirmed and the concentrations of nuclei in the MD and the remainder of the distal convoluted tubules were compared. In the proximal convoluted tubules, salt deprivation caused mitochondrial changes, an increase in intranuclear and cytoplasmic lipid and the deposition of urates. Regional thickening of the glomerular basement membrane was observed in many kidneys. In the normal kidney, there is an age dependent increase in the juxtaglomerular granules in the cortical glomeruli (P less than 0.02), but not in the juxtamedullary glomeruli. In salt deprived birds, juxtaglomerular granules were increased in the juxtamedullary glomeruli (P less than 0.01) but not in the cortical glomeruli. Salt deprivation also caused a significant reduction in bodyweight after five weeks (P less than 0.002) and increases in heterophil (P less than 0.02) and monocyte (P less than 0.05) counts in the blood. 相似文献
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In most species, large variations in body size necessitate dose adjustments based on an allometric function of body weight. Despite the substantial disparity in body size between miniature horses and light‐breed horses, there are no studies investigating appropriate dosing of any veterinary drug in miniature horses. The purpose of this study was to determine whether miniature horses should receive a different dosage of flunixin meglumine than that used typically in light‐breed horses. A standard dose of flunixin meglumine was administered intravenously to eight horses of each breed, and three‐compartmental analysis was used to compare pharmacokinetic parameters between breed groups. The total body clearance of flunixin was 0.97 ± 0.30 mL/min/kg in miniature horses and 1.04 ± 0.27 mL/min/kg in quarter horses. There were no significant differences between miniature horses and quarter horses in total body clearance, the terminal elimination rate, area under the plasma concentration versus time curve, apparent volume of distribution at steady‐state or the volume of the central compartment for flunixin (P > 0.05). Therefore, flunixin meglumine may be administered to miniature horses at the same dosage as is used in light‐breed horses. 相似文献
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Bielanski A. Simard C. Maxwell P. Nadin-Davis S. 《Veterinary research communications》2001,25(8):663-673
The association of bovine immunodeficiency virus (BIV) with embryos derived by in vitro fertilization from oocytes of experimentally infected heifers or oocytes/embryos exposed to the virus in vitro was investigated. Using a nested-PCR assay, proviral DNA of BIV was not detected in follicular fluid or in embryos derived from BIV-infected donors. In vitro exposure of oocytes to BIV during maturation or insemination with BIV-infected semen resulted in zona pellucida-intact embryos testing negative for BIV provirus. However, exposure of zona pellucida-free day-7 embryos to the virus resulted in a positive BIV assay for 28% of the batches of embryos, suggesting that the zona pellucida has a role in protecting against BIV infection. The presence of BIV in the IVF system had no apparent effect on the development of bovine embryos to the blastocyst stage. 相似文献
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Apple JK Wallis-Phelps WA Maxwell CV Rakes LK Sawyer JT Hutchison S Fakler TM 《Journal of animal science》2007,85(3):737-745
Crossbred pigs (n = 185) were used to test the effects of dietary Fe supplementation on performance and carcass characteristics of growing-finishing swine. Pigs were blocked by BW, allotted to pens (5 to 6 pigs/pen), and pens (5 pens/block) were allotted randomly to either negative control (NC) corn-soybean meal grower and finisher diets devoid of Fe in the mineral premix, positive control (PC) corn-soybean meal grower and finisher diets with Fe included in the mineral premix, or the PC diets supplemented with 50, 100, or 150 ppm Fe from Availa-Fe (an Fe-AA complex). When the lightest block averaged 118.2 kg, the pigs were slaughtered, and bone-in pork loins were collected during fabrication for pork quality data. During the grower-I phase, there was a tendency for supplemental Fe to reduce ADG linearly (P = 0.10), whereas in the grower-II phase, supplemental Fe tended to increase ADG linearly (P = 0.10). Even though pigs fed NC had greater G:F during the finisher-I phase (P < 0.05) and across the entire trial (P = 0.07), live performance did not (P > or = 0.13) differ among dietary treatments. There were linear increases in 10th-rib fat depth (P = 0.08) and calculated fat-free lean yield (P = 0.06); otherwise, dietary Fe did not (P > 0.19) affect pork carcass muscling or fatness. Moreover, LM concentrations of total, heme, and nonheme Fe were similar (P > 0.23) among treatments. A randomly selected subset of loins from each treatment was further fabricated into 2.5-cm-thick LM chops, placed on styrofoam trays, overwrapped with polyvinyl chloride film, and placed in coffin-chest display cases (2.6 degrees C) under continuous fluorescent lighting (1,600 lx) for 7 d. During display, chops from NC-fed pigs and pigs fed the diets supplemented with 100 ppm Fe tended to have a more vivid (higher chroma value; P = 0.07), redder (higher a* value; P = 0.09) color than LM chops of pigs fed 50 ppm of supplemental Fe. Moreover, greater (P < 0.01) redness:yellowness ratios in chops from pigs supplemented with 100 ppm Fe indicated a more red color than chops from PC-fed pigs or pigs fed diets supplemented with 50 ppm Fe. In conclusion, however, increasing dietary Fe had no appreciable effects on performance, carcass, or LM characteristics, suggesting that current dietary Fe recommendations are sufficient for optimal growth performance, pork carcass composition, and pork quality. 相似文献
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OBJECTIVE: To investigate feeding practices in infants under the age of 4 months in Liverpool, England with particular reference to the cost of infant feeding. DESIGN: A cross-sectional survey consisting of self-completion questionnaires and interviews. SETTING: Subjects' homes within Central and South Liverpool Primary Care Trust areas. SUBJECTS: One hundred and forty-nine women (aged 18 to 43 years) and their infants (mean age 13 weeks). RESULTS: The average weekly cost of breast-feeding was 11.58 pounds sterling compared with 9.60 pounds sterling for formula-feeding. Many breast- and formula-feeding women spent money however on items that were not needed or used only once or twice. This was especially true of first-time mothers. Characteristics significantly associated with higher spending were: feeding method - mothers that had or were partially breast-feeding (P=0.001), education - those educated to degree level (P=0.028), socio-economic status - those in social classes I and II (P=0.002) and age - those aged 30 years and over (P=0.003). CONCLUSIONS: This study demonstrates that while breast-feeding is often promoted as being free, this is not the case. Better information needs to be given to parents to avoid wasting money on items that are unnecessary, or where cheaper alternatives are available. 相似文献
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Eglinton G Douglas AG Maxwell JR Ramsay JN Ställberg-Stenhagen S 《Science (New York, N.Y.)》1966,153(3740):1133-1135
The most abundant free fatty acids present in a sample of shale from the Green River Formation (Eocene, about 60 x 10(6) years) from Sulfur Creek are the acylic C(19) and C(20) isoprenoid acids. The dominance of these acids parallels the abundance of the corresponding hydrocarbons pristane and phytane. 相似文献