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71.
A 13‐year‐old Romanov sheep presented for evaluation of vaginal discharge, depression and anorexia. Blood work demonstrated mature neutrophilia and marked hyperlactatemia. Transrectal and transabdominal ultrasound revealed echogenic fluid (pus) within the uterus. Purulent uterine fluid culture yield Escherichia coli. A diagnosis of pyometra was made. After medical treatment without clinical improvement, an exploratory laparotomy was performed, and a 360‐degree uterine left horn torsion was identified with the pyometra and multiple corpora lutea on both ovaries. Ovariohysterectomy was performed and the ewe recovered uneventfully.  相似文献   
72.
Second generation Penaeus vannamei broodstack, pond-reared and wild populations, were compared for spawning frequency and several variables associated with reproductive performance. For this purpose, 470 pond-reared and 237 wild-caught individually tagged females were stocked with males of the same origin in ten maturation tanks in a commercial hatchery, and several productivity variables were recorded over time. Results of the analysis indicate that wild shrimp had higher mating and spawning frequencies compared to pond-reared broodstock. The number of nauplii per spawn was higher for wild shrimp, but fertilization and hatching rates were higher for pond-reared spawners. A larger proportion of nonmating females were found in pond-reared shrimp; whereas, wild females had a higher potential for multiple matings. The spawn quality (fertilization and hatching rates, percentage of viable spawns, and number of nauplii) in consecutive matings did not decline substantially. The present study indicates that selection of females with multiple spawning capabilities can be an important commercial strategy to improve nauplii production over the short term. Pond-reared broodstock can be an adequate source for applying this strategy because of their year-round availability and an overall acceptable reproductive performance.  相似文献   
73.
Abstract— The effects of serotonin (5-HT) and the stress of repeated sampling on Penaeus vannamei hemolymph levels of glucose, lactate, triacylglycerol, cholesterol, and total protein were examined. For this purpose, a baseline hemolymph sample was taken and then shrimp were injected with 5-HT (50 μg/shrimp) or saline after which repeated individual samples were taken at 30, 60, and 120 min. Glucose levels tripled in both saline- and serotonin-treated shrimp when compared to baseline values, without any difference between both groups. In contrast, lactate level rose significantly only in the 5-HT group. The levels of this metabolite were significantly higher than in the salineinjection group for all time points. Triacylglycerol decreased in both groups and no substantial differences were observed in cholesterol and protein levels. The results indicate that repeated sampling stress produces strong hyperglycemia and that 5-HT does not produce an additional increase in glucose levels. However. this monoamine strongly increased lactate levels, a response that can be distinguished from stress and probably attributed to glycolysis.  相似文献   
74.
Region of provenance is defined as an area with uniform ecological conditions where stands with similar phenotypic or genetic features are found. This study assesses the effect of differing climate conditions of eight Spanish regions of provenance of Pinus nigra Arn. subsp. salzmannii on earlywood anatomical traits measured in samples from basal discs from mature trees. Results showed that variation in wood biometry between provenances was high and more pronounced than intrapopulation variation. When comparing P. nigra with other Mediterranean pines, high intertracheid wall strength values are associated with better adaptation of pines to arid conditions. However, the intraspecific variations of this parameter in P. nigra did not follow the same pattern, due to the influence of mechanical support requirements. Trees subject to greater aridity were characterised by short tracheids, apparently resulting from their poorer growth, and high frequency of rays and ray parenchyma cells, which would allow trees to store greater amounts of starch, which is the source of metabolites invested in minimising the limitations imposed by water stress. Severe winter cold spells were strongly associated with high axial resin canal frequency and large radial resin canals, creating a powerful, preformed defence system. Increased tracheid lumen involved an increase in the size of bordered pits, favouring sap flow between tracheids, in addition to an increase in the maximum diameter of cross-field pits, favouring the flow of water and metabolites between the axial and radial systems. The high influence of region of provenance on structural variation in P. nigra shows the importance of provenance in the selection of seed origin for reforestation.  相似文献   
75.
The objective of this study was to investigate differences on the endometrial immunoexpression of type I IFN receptor subunit 1 (IFNAR1) and oxytocin receptor (OTR) during the time of maternal recognition of pregnancy in sheep, when oestrus is synchronized with either prostaglandin analogues (group PG) or conventional progestagens (group P). Plasma progesterone was measured from day 0 to 21 post‐coitus (pc) (day 0 = day of oestrus). Immunohistochemistry was performed in samples of uterine horns from pregnant sheep on days 9pc, 13pc, 15pc, 17pc and 21pc to locate IFNAR1 and OTR expression in different endometrial compartments. Mean levels of plasma progesterone were different between treatments, obtaining higher levels in the PG group than in the P group (p < 0.05). Comparing days of pregnancy, IFNAR1 protein expression was different in the luminal epithelium (LE) (p < 0.05), while OTR was different in the LE and in the superficial glandular epithelium (SG) (p < 0.05). Temporal variation on the expression of both proteins from day 9pc to 21pc has been evidenced. IFNAR1 and OTR expression did not show significant differences between treatments. However, the response observed in the endometrium was highly inconsistent when prostaglandin analogues were used. Therefore, the protocol based on prostaglandin analogues still needs to be optimized before being considered as a better alternative to progestagens for oestrous synchronization in sheep.  相似文献   
76.
The objective of this study was to optimize protocols for the cryopreservation of sex‐sorted boar spermatozoa. In the experiment 1, we evaluated the effects of a standard boar sperm cryopreservation procedure (3% final glycerol concentration) on the in vitro characteristics of sex‐sorted sperm frozen at low sperm concentrations (20 × 106 sperm/ml; S20 group). Non‐sorted spermatozoa frozen at 1000 × 106 (C1000 group) and 20 × 106 (C20 group) sperm/ml were used as the freezing control groups. In experiment 2, the effects of different final glycerol concentrations (0.16%, 0.5%, 1.0%, 2.0% and 3.0%) on post‐thaw quality of the S20 and C20 groups were evaluated. In both experiments, the samples were evaluated prior to freezing (5°C) and at 30, 90 and 150 min after thawing. Experiment 1 indicated that freezing sperm at low concentrations decreased (p < 0.05) the total motility (TM) and progressive motility (PM) at 90 and 150 min after thawing regardless of whether the sperm were sorted or not. However, the sperm membrane integrity was not affected at any evaluation step. Inexperiment 2, significant effects on the TM and PM because of increased glycerol concentrations in the S20 and C20 groups were observed only at 90 and 150 min after thawing. The samples frozen in 3% glycerol showed lower (p < 0.05) TM and PM values when compared to those frozen in the presence of 0.5% and 1% glycerol. In both experiments, non‐sorted control samples displayed higher percentages of spermatozoa with damaged DNA than sorted spermatozoa. In conclusion, the optimization of cryopreservation conditions by decreasing the glycerol concentrations can improve post‐thaw motility of sex‐sorted spermatozoa frozen at low concentrations.  相似文献   
77.
This study was conducted to measure the concentration of cefquinome in the endometrium of mares after intrauterine treatment and to evaluate associated inflammation. Mares (n = 14) were randomly assigned to one of the following groups: (i) control (n = 4) were either not treated (n = 2) or received (n = 2) lactated Ringer's intrauterine for 1 or 3 days; (ii) treated mares (n = 10) received intrauterine cefquinome for 1 or 3 days. After at least 10 days had passed following the last treatment and ovulation, mares were given Prostaglandin F2α (PGF2α) and were randomly assigned to an alternate treatment. Endometrial biopsy samples were taken at 2, 8, 24 and 48 h, or at 4, 12 and 36 h, after the last treatment. Biopsy samples were taken at the same time points from control mares (n = 2) and lactated Ringer-treated mares (n = 2). Cefquinome concentrations were quantified using a high-performance liquid chromatography (HPLC) assay and inflammation was assessed using haematoxylin and eosin (H&E)-stained sections. Concentrations of cefquinome [559 (1 day) and 595 μg/g (3 days) at 2 h, and 403 (1 day) and 370 μg/g (3 days) at 4 h] were similar between treatment groups at 2 and 4 h after treatment (p > 0.05). At 8 h, as well as at 24 and 48 h, concentrations were greater in the 3-day group (17 vs 301 μg/g, 3 vs 80 μg/g and 0.1 vs 0.2 μg/g, respectively) (p < 0.05). No significant differences (p > 0.05) in the inflammatory response at 2–48 h after treatment were found between groups.  相似文献   
78.
Between June 2008 and March 2009, 87 cats in Australia developed symmetrical hindlimb ataxia, paraparesis, tetraparesis, paraplegia or tetraplegia in association with eating an imported, irradiated dry pet food. This communication reports the clinical signs and outcomes of those cats.  相似文献   
79.
The incidence of early foetal loss is increasing under intensive management systems for dairy cattle. The aims of the present study were to determine whether there is any peak period of pregnancy loss during the early foetal period and to evaluate possible differences between single and twin pregnancies. The study population consisted of 1442 pregnant cattle from a single herd. Pregnancy was diagnosed by transrectal ultrasonography between 36 and 42 days after insemination, and then weekly until day 90 of gestation or until pregnancy loss. A total of 1310 cows (90.8%) bore single embryos and 132 (9.2%) carried twins. Pregnancy loss was registered in 139 (9.6%) cows before day 90 of pregnancy: 101 (7.7%) in single and 38 (28.8%) in twin pregnancies. The average time of pregnancy loss for all animals was 58.4 ± 12.6 days and ranged from 45 to 90 days. Seventy‐five per cent of the pregnancy losses were registered between 45 and 60 days of gestation. The average time of pregnancy loss for cows with singletons was 52.1 ± 4.1 days and ranged from 45 to 61 days and that for those with twins was 75.1 ± 12.4 days and ranged from 46 to 90 days. Seventy‐five per cent of the twin pregnancy losses were registered between 68 and 90 days of gestation. Our data show that the foetal loss in singleton pregnancies occurs earlier than in twin pregnancies. Assessment of normal development of gestation on days 60 and 90 after insemination is suggested.  相似文献   
80.
In the absence of commercially viable methods for cryopreserving turkey spermatozoa, new processing methods are required to extend the functional life of stored turkey spermatozoa for artificial insemination. The present study evaluates the efficacy of a new extender (Turkey Semen Extend) and investigates the use of density gradient centrifugation in processing turkey spermatozoa for artificial insemination. The new extender is compared with two commercially available turkey semen extenders, Beltsville Poultry Semen Extender and Ovodyl. Turkey spermatozoa in Turkey Semen Extend were still motile 20 h after collection, representing a considerable improvement over the other semen extenders (40%, 0% and 8% for Turkey Semen Extend, Beltsville Poultry Semen Extender and Ovodyl, respectively). A field trial on a commercial turkey farm showed improved fertilization rates following insemination of turkey hens with semen extended in Turkey Semen Extend (89.7%) compared with Beltsville Poultry Semen Extender (86.9%). This difference is statistically significant (p < 0.05). Processing on a density gradient, optimized for turkey spermatozoa, also increased sperm survival (50% gradient-prepared spermatozoa still motile after 18 h compared with <10% non-processed spermatozoa). Preliminary studies indicate that gradient preparation of spermatozoa may aid survival during cryopreservation.  相似文献   
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