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1.
The effect of organic phosphorus on metabolic, haematological and hormonal status, restoration of ovarian functions and conception rate in anoestrous Farafra ewes in subtropics were evaluated. Anoestrous Farafra ewes (n  = 24; 34.72 ± 0.52 kg body weight) were allocated into two equal groups: control and phosphorus groups. The ewes of phosphorus group were treated with sodium 4‐dimethylamino‐2‐methyl‐phenyl‐phosphonate as an organic bound phosphorous twice a week for successive 3 weeks. Ovarian follicle development and corpora lutea were checked three times a week till occurrence of oestrus using ultrasonography while pregnancy was confirmed at 30 days post‐service. Plasma metabolites, reproductive hormones, thyroid hormones and minerals were detected at weeks ?2, ?1, 0 (mating day) and + 4 weeks post‐oestrus. Phosphorus group had significantly (p  < .05) short interval to oestrous resumption if compared to control ewes (2.1 ± 0.8 weeks vs . 4.6 ± 1.1 weeks). In addition, phosphorous supplementation significantly (p  < .05) increased the number of antral follicles (developed and their sizes in addition to sizes of corpora lutea (8.72 ± 0.3 mm vs . 7.46 ± 0.9 mm) as well. Number of services per conception (2.6 vs . 1.4; p  < .01) was higher in control group than that of phosphorus group. Pregnancy rate (80 vs . 50%) was significantly (p  < .01) higher in phosphorus group when compared to control. White blood cells in treated ewes (10.8 ± 0.44; p  < .05) and monocytes (2.93 ± 0.13; p  < .01) were higher than that of control group (white blood cells; 9.53 ± 0.50 and monocytes; 2.24 ± 0.14). Metabolic parameters did not differ between phosphorus and control groups during different times of treatment. It could be concluded that phosphorous administration to anoestrous Farafra ewes in subtropics could improve reproductive performance and restore ovarian activity at the end of spring and early summer.  相似文献   
2.
畜产品安全与毒害物质残留研究进展   总被引:2,自引:0,他引:2  
论述了畜产品安全及其目前畜产品中的兽药、激素、重金属、生物毒素、农药、微生物等毒害物质的残留,并对畜产品安全现状及存在的问题进行了分析。  相似文献   
3.
Bupivacaine is available as a racemic mixture of its enantiomers, d -bupivacaine and l -bupivacaine (LB). The aim of this randomized, double-blind study was to investigate the clinical efficacy and safety of S(−)-bupivacaine compared with standard racemic bupivacaine (RB) in horses under caudal epidural analgesia. Two treatments were administered to each horse, with a 2-week interval between subsequent treatments. Treatment 1 consisted of 0.5% LB at a dose of 0.06 mg/kg of body weight, and treatment 2 consisted of 0.5% RB at a dose of 0.06 mg/kg of body weight. Epidural injections were given in all animals between the first and second coccygeal vertebra. Heart rate (HR), arterial pressures, respiratory rate (RR), rectal temperature (RT), analgesia, and motor blocking were determined before drug administration (basal) and 5, 10, 15 and 30 min after drug administration, and at 30 min intervals thereafter. There were no significant differences between the two treatments in the quality of sensory and motor block. The duration of analgesia was 320 ± 30 min (mean ± SD) for RB and 360 ± 42 min for LB. HRs and RRs, arterial pressures and RT did not change ( P  < 0.05) significantly from basal values after epidural administration of LB or RB. This study supports that 0.5% LB is an effective alternative to RB in caudal epidural analgesia in conscious, standing horses. The use of LB vs. RB warrants further investigation, particularly for long-lasting surgery in the perineal region.  相似文献   
4.
Four isocaloric‐isonitrogenous diets containing 0, 50, 100 and 190 g/kg corn protein concentrate (CPC) as replacement for dietary fish meal were fed to Nile tilapia Oreochromis niloticus fingerlings for 8 weeks. Tilapia growth parameters were not significantly (p > .05) different in fish fed diets with 0, 50 and 100 g/kg CPC and found to be superior compared to those fed on 190 g/kg CPC. Fish dressing ratios and body composition were similar among all treatments. The electron microscope indicated that the stomach size of control fish was slightly smaller and the wall was thinner while the stomach of the fish fed all other levels of CPC undergone a remarkable size increase and their walls were thicker after feeding diets with CPC. Total aerobic bacterial and coliform counts were significantly decreased in fish intestine when fed diets with 100 and 190 g/kg CPC compared with fish fed diets with 0 g/kg or 50 g/kg CPC. This study indicates that it is possible to replace up to 534 g/kg of dietary fish meal in tilapia fingerlings using 100 g/kg of CPC without any negative effect on fish growth and proximate body composition.  相似文献   
5.
Objective: To compare surgical times and perioperative complication rates of single portal access and 2-portal laparoscopic ovariectomy (LapOVE) in dogs using a bipolar vessel sealer/divider device, and to evaluate the performance of novice laparoscopists for right ovariectomy.
Study Design: Controlled clinical trial.
Animals: Female dogs (n=42).
Methods: Dogs were divided into groups: 1=single portal and 2=2 portal. LapOVE was performed using a 5 mm vessel sealer/divider device and a 10 mm operating laparoscope (Group 1) or a 5 mm laparoscope (Group 2). Dog characteristics (weight, body condition score, ovarian ligament fat score), operative time, and perioperative complication rate were compared between groups. Right ovariectomy duration was evaluated for 2 novice laparoscopists.
Results: No significant difference was found in mean total surgical time between group 1 (21.07 min/s) and group 2 (19.06 min/s). Factors significantly affecting times included body condition scores, ovarian ligament fat score, ovarian bleeding, and surgeon expertize. Minor complications (bleeding from ovaries or after splenic trauma) occurred and were similar in both groups. Bleeding was correlated to body condition score and ovarian ligament fat score. Interindividual differences were found among surgeons for right ovariectomy time.
Conclusions: Single portal access LapOVE using vessel sealer/divider device is feasible, safe, and does not significantly increase total surgical time in comparison with 2-portal approach. Laparoscopic skills may play a role in ability to perform single portal LapOVE.
Clinical Relevance: LapOVE can be performed using single portal access.  相似文献   
6.
We used a dataset assembled by the Peruvian Marine Research Institute (IMARPE) from 1961 to 2005, to examine the influence of seasonal, environmental (temperature and salinity), temporal (day–night and year) and location (north‐south and on‐off shelf) variables on the distribution and biovolume of zooplankton. Classification and regression trees (CART) showed that the zooplankton distribution can be divided into four time regimes: prior to 1974.5, 1974.5–1989.5, 1989.5–1997.5 and 1997.5–2005. These periods differ in overall biovolume but, more importantly, in having different spatial distributions of variables. Offshore‐onshore, seasonal, diel and north‐south patterns are all apparent in the temporal changes observed in zooplankton distribution. In the early period zooplankton biovolume was high throughout the Peruvian Humboldt Current Ecosystem, with enhanced biovolume in all seasons but winter. After 1974.5, biovolume was considerably lower. There was an increased difference between the shelf (lower biovolume) and offshore (higher biovolume), with a significant day–night effect offshore, due to diel migration and possibly diel catchability changes. After 1989.5, seasonal effects were more marked and biovolume appeared to be higher in the winter in the northern region. In other seasons, during the daytime, biovolume was highest farther offshore (greater than 65 km offshore of the 200‐m isobath) and, during the night, higher after 1997.5 than before. We relate these changes in distribution and biovolume to changes in large‐scale current patterns in different regimes and to the possible effect of the fishery in removing nutrients from the system.  相似文献   
7.
High-power and highly directional semiconductor microcylinder lasers based on an optical resonator with deformed cross section are reported. In the favorable directions of the far-field, a power increase of up to three orders of magnitude over the conventional circularly symmetric lasers was obtained. A "bow-tie"-shaped resonance is responsible for the improved performance of the lasers in the higher range of deformations, in contrast to "whispering-gallery"-type modes of circular and weakly deformed lasers. This resonator design, although demonstrated here in midinfrared quantum-cascade lasers, should be applicable to any laser based on semiconductors or other high-refractive index materials.  相似文献   
8.
A quantum-cascade long-wavelength infrared laser based on superlattice active regions has been demonstrated. In this source, electrons injected by tunneling emit photons corresponding to the energy gap (minigap) between two superlattice conduction bands (minibands). A distinctive design feature is the high oscillator strength of the optical transition. Pulsed operation at a wavelength of about 8 micrometers with peak powers ranging from approximately 0.80 watt at 80 kelvin to 0.2 watt at 200 kelvin has been demonstrated in a superlattice with 1-nanometer-thick AlInAs barriers and 4.3-nanometer-thick GaInAs quantum wells grown by molecular beam epitaxy. These results demonstrate the potential of strongly coupled superlattices as infrared laser materials for high-power sources in which the wavelength can be tailored by design.  相似文献   
9.
The purpose of the present study was to provide a detailed computed tomography (CT) and cross‐sectional anatomic reference of the normal metatarsus and digits for the camel and buffalo, as well as to compare between metatarsus and digits in these animals to outstand a basis for diagnosis of their diseases. Advantages, including depiction of detailed cross‐sectional anatomy, improved contrast resolution and computer reformatting, make it a potentially valuable diagnostic technique. The hind limbs of 12 healthy adult camel and buffalo were used. Clinically relevant anatomic structures were identified and labelled at each level in the corresponding images (CT and anatomic slices). CT images were used to identify the bony and soft tissue structures of the metatarsus and digits. The knowledge of normal anatomy of the camel and buffalo metatarsus and digits would serve as initial reference to the evaluation of CT images in these species.  相似文献   
10.
This study was conducted to characterize the daily profile of testosterone secretion and its mean concentrations in the four seasons as well as to evaluate the semen characteristics and testicular biometry of Mangalarga Marchador stallions throughout the year in a tropical region. Three stallions were submitted to semen collections and evaluation of testicular biometry every 14 days along a year. Blood samples were collected once at the middle of each season, in a 20‐min interval during 24 hr in order to evaluate the testosterone secretion profiles among seasons. Testosterone concentrations along the day were higher at the beginning of the afternoon (from 12:00 to 15:00 hr), but a circadian secretion was not clearly observed. Mean testosterone concentrations did not differ among seasons (p > .05), but a pattern of secretion along the day showed variations with higher concentrations in the afternoon during the winter. Ejaculate volume was higher during summer; however, sperm motility decreased in summer and spring. Total sperm in ejaculate, sperm morphology and testicular biometry kept constant along the year showing no differences among the seasons. The results demonstrated that in a tropical region, reproductive aspects of stallions did not show a clearly defined seasonal variation, and months of autumn and winter were not unsuitable for reproduction of the males.  相似文献   
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