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排序方式: 共有227条查询结果,搜索用时 15 毫秒
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Fred A. Williams JR DVM Ronald M. Bright DVM MS Diplomate ACVS Gregory B. Daniel DVM MS Diplomate ACVR Kevin A. Hahn DVM PhD Steve A. Patton DVM MS Diplomate ACVP 《Veterinary surgery : VS》1999,28(5):348-354
OBJECTIVE: To determine if once-daily colonic irrigation results in fecal continence for a 24-hour period in dogs with colostomies and if colonic volume increased in response to the irrigation. STUDY DESIGN: A prospective controlled experimental study. ANIMALS: Four intact male and one intact female mixed breed dogs. MATERIALS: All dogs received left end-on paralumbar colostomies. Four dogs received once-daily colonic irrigation for 8 weeks, whereas the control dog did not. Daily fecal weights were recorded for the length of the study in all dogs. Barium enema studies and volumetric studies were used to determine colonic volumes. RESULTS: Daily fecal weights were significantly decreased in treatment dogs compared with the control dog. Colonic volume increased in irrigated dogs in response to daily irrigation over the 8 week period of the study. CONCLUSIONS: Colonic irrigation resulted in significantly decreased fecal production over a 24-hour period. Therefore management of dogs with colostomies would be more practical and cost effective. It did not result in complete fecal continence in this study. Further clinical studies are indicated to determine if longer periods of irrigation would result in complete continence. 相似文献
34.
Abstract This study on reef placement involves two aspects: (1) the development of a bioenergetics model for red snapper, Lutjanus campechanus (Poey), in Gulf of Mexico waters off the coast of Alabama, where significant numbers of artificial reefs are thought to exist, and (2) a fuzzy rough set model by which parameters determined from the bioenergetics model can provide a decision tool for optimally spacing artificial reefs during deployment. The bioenergetics and consumption rates of L. campechanus by age class foraging on artificial reefs in the Gulf of Mexico off the coast of Alabama provided input into the fuzzy rule‐based model. After conducting multiple simulations, highest certainty in optimal reef spacing was achieved for reef distances between 0.50 and 0.95 km such that no more than two fit within a 1‐km2 area. Results can inform fisheries managers about placement of artificial reefs to affect the health and survival of reef‐associated species. 相似文献
35.
E.L.C. BALLESTER P.C. ABREU R.O. CAVALLI M. EMERENCIANO L.
De ABREU W. WASIELESKY JR 《Aquaculture Nutrition》2010,16(2):163-172
Farfantepenaeus paulensis juveniles (72 ± 24 mg), were reared in a suspended microbial flocs system and fed practical diets containing increasing amounts of crude protein (250, 300, 350, 400 and 450 g kg?1 CP). Development of microbial flocs was promoted by high aeration rates and fertilization with wheat bran and molasses. Flocs were composed of detritus in the form of flocculated matter colonized by heterotrophic bacteria, cocoid and filamentous cyanobacteria, flagellate and ciliate protozoa and rotifers. Proximate composition analysis of the suspended microbial floc showed CP levels of 304 g kg?1. After 45 days, mean shrimp survival were above 89%, with no significant differences between treatments. Shrimp fed diets with 350 g kg?1 or higher CP content achieved significant higher (P < 0.05) final weight (0.66–0.68 g), weight gain (0.58–0.61 g) and instantaneous growth rate (0.049–0.050), with feed conversion rates (2.17–2.30) significantly lower (P < 0.05). Results show that, when rearing is carried out in a suspended microbial flocs system, dietary CP levels can be kept at 350 g kg?1. Furthermore, results confirm that microbial‐based systems allow shrimp culture without compromising the surrounding environment and shows the possible reduction of production costs and fish meal dependence. 相似文献
36.
Equine amnionitis and fetal loss: The case definition for an unrecognised cause of abortion in mares
KH Todhunter NR Perkins RM Wylie C Chicken AJ Blishen DJ Racklyeft G Muscatello MC Wilson PL Adams JR Gilkerson WL Bryden AP Begg 《Australian veterinary journal》2009,87(1-2):35-38
A series of abortions occurred in mares in New South Wales during 2004 that involved similar and unusual findings on post mortem examination of aborted fetuses and fetal membranes. The term Equine Amnionitis and Fetal Loss (EAFL) was developed to describe the condition. This form of abortion had not been previously recognised in Australia. The pathology alone is not specific for EAFL and diagnosis requires demonstration of a combination of certain pathological and bacteriological features. The purpose of this paper is to describe patterns considered consistent with EAFL cases as a working case definition for use by veterinarians and veterinary pathologists in identifying future cases of EAFL. More detailed papers are in preparation to fully describe the epidemiological, histopathological, and microbiological aspects of EAFL. 相似文献
37.
Organogenesis and foetal haemodynamics during the normal gestation of healthy black‐rumped agoutis (Dasyprocta prymnolopha,Wagler, 1831) bred in captivity
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FCA Sousa GT Pessoa LS Moura JR Araújo RPS Rodrigues MAPS Barbosa AN Diniz AB Souza EG Silva LU Lucena MP Sanches OF Silva‐Filho PC Guerra JM Sousa WC Neves FR Alves 《Reproduction in domestic animals》2017,52(1):60-66
The objective of this study was to define the patterns of organogenesis and foetal haemodynamics during the normal gestation of healthy agoutis (Dasyprocta prymnolopha) kept in captivity. Thirty pregnant agoutis that ranged in size from small to medium and weighed between 2.5 and 3 kg underwent B‐mode and Doppler ultrasonography for the biometric evaluation of the foetal organs. The foetal aortic blood flow proved to be predominantly systolic, and the measured flow velocity was 78.89 ± 2.95 cm/s, with a maximum pressure gradient of 2.12 ± 0.27 mmHg. The liver was characterized by its large volume, occupying the entire cranial aspect of the abdominal cavity, and it was associated cranially with the diaphragm and caudally with the stomach. The flow velocity in the portal vein was estimated to equal 12.17 ± 2.37 cm/s, with a resistivity index of 0.82 ± 0.05. The gallbladder was centrally located and protruded cranially towards the diaphragm. The spleen was visualized as an elongated structure with tapered cranial and caudal extremities, and the foetal kidneys were visualized bilaterally in the retroperitoneal region, with the right kidney positioned slightly more cranially than the left. The morphological characterization and hemodynamic analysis of the foetal organs of black‐rumped agoutis via B‐mode and Doppler ultrasonography allow determination of the vascular network and of reference values for the blood flow required for perfusing the anatomical elements essential for maintaining the viability of foetuses at different gestational ages. 相似文献
38.
Effect of exogenous progesterone administration on luteal sensitivity to PGF during the early development of the corpus luteum in mares and cows
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A Garcia‐Muñoz X Valldecabres‐Torres JR Newcombe J Cuervo‐Arango E Garcia‐Rosello 《Reproduction in domestic animals》2017,52(6):1074-1080
The objective of this study was to determine the effect of exogenous progesterone administration at ovulation and during the early development of the CL, on its future sensitivity to a single administration of PGF2a in mares and cows. Horse Retrospective reproductive data from an equine clinic in the UK during three breeding seasons were used. Mares were divided into: control group, cycles with single ovulations; double ovulation group cycles with asynchronous double ovulations; and PRID group: cycles with single ovulations and treatment with intravaginal progesterone device (CIDR) immediately after the ovulation. All mares were treated with d‐cloprostenol (PGF) at either: (i) 88 hr; (ii) 96 hr; (iii) 104 hr; or (iv) 112 hr after the last ovulation. Cattle A total of nine non‐lactating Holstein cows were used. All cows were administered PGF14 d apart and allocated to one of two groups control group GnRH was administered 56 hr after the second PGF administration. CIDR group CIDR was inserted at the same time of GnRH administration. All cows were administered PGF at 120 hr post‐ovulation. The complete luteolysis rate of mares with double ovulation (66.7%) and those treated with exogenous progesterone (68.4%) was significantly higher than the rate of mares with single ovulation (35.6%) at 104 hr. In the cow, however, the treatment with CIDR did not increase the luteolytic response in cows treated at 120 hr post‐ovulation. In conclusion, the degree of complete luteolysis can be influenced by increasing the concentration of progesterone during the early luteal development in mares. 相似文献
39.
TA Abdulkareem SAM Al‐Sharifi MA Ishak SM Eidan MA Alnimr CW Passavant JR Branen RG Sasser 《Reproduction in domestic animals》2011,46(3):455-462
This study was undertaken to detect pregnancy in Iraqi riverine buffalo (Bubalus bubalis) using three different methods (rectal palpation, plasma progesterone concentration and detection of the presence of pregnancy‐specific protein B (PSPB) with the BioPRYN® enzyme‐linked immunosorbent assay (ELISA) test. The aim of the study was to identify the most sensitive, early and accurate method for detecting pregnancy. Twenty‐two female riverine buffalo that were 6.0 ± 0.93 years old were used. Four blood samples per buffalo were taken via jugular venipuncture at days 22–24, 32–34, 42–44 and 58–61 post‐mating (PM) to measure the progesterone concentration (ng/ml) and to detect the presence of plasma PSPB. The rectal palpation method was employed to evaluate all buffalo on days 42–44 and 58–61 PM. The BioPRYN® test differed (p < 0.01) from the other tests with earlier accuracy for detecting pregnant and non‐pregnant buffalo. Eighty‐eight percent of pregnant and 76.9% of non‐pregnant buffalo were distinguished early (days 22–24 PM) using BioPRYN® and plasma PSPB‐ELISA level (2.09 ± 0.12 ng/ml) in relation to 66.7% and 53.9% detected using the progesterone assay at similar days (4.30 ± 0.40 ng/ml). In conclusion, these results described, for the first time, the early and accurate pregnancy detection of water riverine buffalo using BioPRYN® technology and provided the plasma levels of PSPB using an ELISA test. These findings will improve the reproductive and productive efficiency of Iraqi riverine buffalo by adapting the recent management and reproductive strategies in Iraq and in the world. 相似文献
40.
DM Magalhães DD Fernandes MBS Mororó CMG Silva GQ Rodrigues JB Bruno MHT Matos CC Campello JR Figueiredo 《Reproduction in domestic animals》2011,46(1):134-140
The aim of the present study was to evaluate the effects of different medium replacement intervals on the viability, antral cavity formation, growth and in vitro maturation (IVM) of oocytes from caprine and ovine pre‐antral follicles. Pre‐antral ovarian follicles (≥150 μm) were isolated from the ovarian cortex of goats and sheep and were individually cultured for 24 days using two different medium replacement intervals [2 days (T1) or 6 days (T2)]. Follicle development was evaluated on the basis of antral cavity formation, increases in follicular diameter and the presence of healthy cumulus oocyte complexes and fully grown oocytes. For caprine species, results showed a higher percentage (p < 0.05) of viable follicles in T1 than T2 from day 6 until the end of the culture. In addition, when comparing both treatments after the same culture duration, the rate of antrum formation was significantly higher in T1 than in T2 from day 12 onwards. Yet, in ovines, when both treatments were compared on day 24 of the culture, there were more viable follicles in T2 than in T1 (p < 0.05). In the caprine species, percentages of fully grown oocytes (≥110 μm) acceptable for IVM after 24 days of culture were significantly higher in normal follicles cultured in T1 (30.0%) than in T2 (6.7%; p < 0.05). On the other hand, in ovines, at the end of the culture, the percentage of oocytes destined for IVM was higher in T2 than in T1 (23.5% vs 2.9%; p < 0.05). In conclusion, under the same conditions, the frequency of medium replacement significantly affected the in vitro development of caprine and ovine pre‐antral follicles. To improve the efficiency of the culture system, the medium must be replaced every 2 and 6 days for goat and sheep pre‐antral follicles, respectively. 相似文献