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881.
882.
Julia E.  Tomlinson  BVSc  Kelly  Farnsworth  DVM  MS  Abby M.  Sage  DVM  MS  Tracy A.  Turner  DVM  MS  Julia H.  Wilson  DVM 《Veterinary radiology & ultrasound》2001,42(4):349-351
Ultrasound-guided percutaneous pyelography has previously been used in dogs to diagnose ectopic ureter. To the authors' knowledge its use has never been reported in the horse. This paper reports the technique used in a three-week-old filly with a suspected ectopic ureter. Pyelography can be performed under sedation and is a relatively simple, safe procedure. The technique enables assessment of individual renal function through collection and analysis of urine from each renal pelvis.  相似文献   
883.
The effect of Escherichia coli lipopolysaccharide (LPS) on the expression of major histocompatibility complex (MHC) class II molecules by bovine mammary macrophages was examined. The ability of LPS-treated mammary macrophages to support antigen-specific T-cell proliferation, as a measure of their antigen presentation ability, was also evaluated. For this purpose, control and LPS-treated macrophages were pulsed with heat-killed Staphylococcus aureus and then cultured with S. aureus-sensitized T-cells. Our data show that LPS had no significant effect on the expression of MHC class II molecules on the surface of mammary macrophages. Furthermore, LPS-induced macrophages were no more active in supporting T-cell proliferation on a per cell basis than unstimulated macrophages. The lack of macrophage response to LPS with respect to expression of MHC class II molecules and the antigen presentation ability is another example of the hyporesponsive nature of macrophages isolated from the bovine mammary gland.  相似文献   
884.
A case of hypertrophic osteopathy secondary to a pulmonary spindle cell sarcoma is described. The 9‐year‐old male cat presented with a 1‐month history of decreased appetite, decreased activity and progressive lameness with swelling and pain of all four limbs. Thoracic radiographs showed a soft tissue opaque mass in the left caudal lung lobe. Radiographs of all limbs showed extensive periosteal new bone formation of uniform opacity demonstrating a ‘palisading’ pattern. The lung mass was removed at exploratory thoracotomy; histopathological examination diagnosed a low‐grade spindle cell sarcoma. Prior to surgery, the cat had a non‐specific conjunctivitis that resolved spontaneously following lobectomy raising the possibility of a paraneoplastic association. The lameness also resolved; six months after surgery, the periosteal palisading of new bone on the long bones had remodelled, and there was no evidence of pulmonary metastases.  相似文献   
885.
The objectives of the study were to (a) develop a simple fecal progestin extraction and radioimmunoassay method to measure immunoreactive progestin in porcine feces and (b) to characterize fecal progestin profiles during the estrous cycle and postpartum. A simple extraction method was developed in trial 1 and the mean (+/- SD) progestin recovery of the method was 84.3 +/- 3.5%. Progesterone levels measured at five different spiked concentrations (50, 100, 200, 400, and 500 ng/0.5 g feces) showed no systematic error. The sensitivity of the assay was 0.16 nmol/L of the extract. Trial 2 involved collecting fecal samples from six cycling sows every second or third day, beginning on the day of estrus (day 0) and continuing until day 22. The mean (+/- SD) fecal progestin concentrations of these sows determined by the above assay during days 0-5, days 6-10, days 11-15, and days 16-21 were 87.1 +/- 17.5, 262.6 +/- 102.1, 1188.2 +/- 454.1, and 897.3 +/- 274.1 x 10(-3) nmol/g feces, respectively. In trial 3, fecal samples from six postpartum sows were collected at weekly intervals beginning from day 7 after farrowing until day 50. The mean (+/- SD) fecal progestin concentrations were 111.0 +/- 61.1, 74.1 +/- 21.3, 66.5 +/- 26.1, 122.7 +/- 58.8 and 533.5 +/- 244.2 x 10(-3) nmol/g feces, during days 7-10, days 11-20, days 21-30, days 31-40, and days 41-50 postpartum, respectively. The results indicate that simple fecal progestin extraction and assay are feasible alternatives to the standard blood progesterone assays for monitoring reproductive function in swine.  相似文献   
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The present study assessed effects of diets containing varying calcium–phosphorus (CaP) concentration and fermentable substrates on digestibility of diets, intestinal microbiota and immune system using 32 crossbred pigs (initial BW 54.7 kg). In a 2 × 2 factorial arrangement, pigs were fed either a corn–soybean meal (CSB) or corn–field pea (CFP) diet with either low [‐] (4.4 g Ca/kg; 4.2 g total P/kg) or high [+] (8.3 g Ca/kg; 7.5 g total P/kg; supplemented with monocalcium phosphate) CaP content for a period of 9 weeks. In week 8, blood samples were taken, and at the end of the trial, all pigs were euthanized to collect digesta and mesenteric lymphoid tissue. Apparent total tract digestibility (ATTD) of P was greater (p < 0.05) for pigs fed the CaP+ and CFP diets than CaP‐ and CSB diets. The myo‐inositol 1,2,3,4,5,6‐hexakis (dihydrogen phosphate) (InsP6) concentration in jejunal digesta was higher (p < 0.05) for CaP+ than in CaP‐ fed pigs. In addition, caecal and faecal InsP5 isomer concentration were greater (p < 0.05) for CSB than CFP diets. In the caecum, gene copy numbers of saccharolytic bacteria, such as Eubacterium rectale and Roseburia spp., as well as SCFA concentration were higher (p < 0.05) for CaP+ than CaP‐ diets. In particular, innate immune cell numbers, such as natural killer cells, dendritic cells, monocytes and neutrophils, were greater (p < 0.05) for CaP+ than CaP‐ fed pigs. Diets high in CaP resulted in higher abundance of potential beneficial bacteria and might promote the first line of defence enhancing the activation of the cellular adaptive immune response, thereby possibly decreasing the risk for intestinal disturbances. These results strongly suggest that both, CaP supply and dietary ingredients differing in fermentability, may beneficially affect gut health through increase in SCFA‐producing bacteria and/or bacteria with anti‐inflammatory properties.  相似文献   
888.
Chromosomal abnormalities are a major cause of infertility and reproductive problems in equids. Nowadays, their detection is rising due to the use of new diagnostic tools based on molecular markers instead of karyotyping. Reports of this kind of genetic aberrations in domestic donkeys (Equus asinus) are extremely scarce, despite their importance in human activities. In the present study, we analysed the implementation of a short‐tandem‐repeat (STR)‐based molecular method initially developed for horses, as a diagnostic tool to detect chromosomal abnormalities in donkeys. The frequency of five X‐linked (LEX003, LEX026, TKY38, TKY270 and UCEDQ502) and one Y‐linked (ECAYM2) molecular markers and one Y‐linked gene (sex‐determining region Y, SRY) was characterized in 121 donkeys from two diverse breeds, the Spanish Andalusian and the African Moroccan breeds. The molecular panel showed 100% sensitivity and 99.67% specificity in detecting 10 different chromosomal abnormalities in the species. In conclusion, this methodology is a valid, rapid and low‐cost tool for the detection and characterization of chromosomal abnormalities in domestic donkeys.  相似文献   
889.
890.
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