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1.
Spermatic and oxidative profile of domestic cat (Felis catus) epididymal sperm subjected to different cooling times (24, 48 and 72 hours) 下载免费PDF全文
DSR Angrimani KK Nagai BR Rui LC Bicudo JDA Losano MM Brito MCP Francischini M Nichi 《Reproduction in domestic animals》2018,53(1):163-170
Cooling stored epididymal samples for several days allows facilities to transport and process genetic material post‐mortem. Improvements to this practice allow the preservation of sperm from domestic cats, which are the ideal study model for wild felids. However, the modifications in spermatic features and the oxidative profile are not fully understood in cats. This information is necessary for the development of biotechniques, such as new extenders for cryopreservation. Therefore, the purpose of this study was to evaluate the spermatic and oxidative profile in samples from the epididymal cauda of domestic cats cooled at 5°C for 24, 48 and 72 hr. Spermatozoa were collected from the epididymis cauda. Evaluations consisted of computer‐assisted sperm analysis (CASA), plasma membrane integrity (eosin/nigrosin), acrosome integrity (fast green/rose bengal), sperm morphology, sperm DNA integrity (toluidine blue), mitochondrial activity (3′3 diaminobenzidine), activity of the antioxidant enzymes glutathione peroxidase (GPx) and superoxide dismutase (SOD), measurement of lipid peroxidation (TBARS) and protein oxidation. A decrease in sperm motility parameters was observed after 72 hr of cooling (i.e. total and progressive) with a higher percentage of minor (37.7 ± 6.3%) and total defects (53.4 ± 6.3%). Additionally, a decrease in high mitochondrial activity (Class I: 16.6 ± 2.2%) occurred after 72 hr. The decrease in motility rates after a long cooling time probably was caused by the increase in sperm abnormalities. A long cooling time causes cold shock and mitochondrial exhaustion, but there was no observed change with the oxidative stress condition. Therefore, cat epididymal sperm stored at 5°C appear to maintain a high quality for up to 48 hr of cooling time. 相似文献
2.
A fast,low‐cost and efficient method for the diagnosis of sperm DNA fragmentation in several species 下载免费PDF全文
BR Rui DSR Angrimani LC Bicudo JDA Losano M Nichi RJG Pereira 《Reproduction in domestic animals》2018,53(1):171-175
Sperm DNA fragmentation is a condition that interferes directly in the reproductive efficiency. Currently, there are several methods for assessing the sperm DNA integrity, such as Alkaline Comet, TUNEL and Sperm Chromatin Structure Assay. However, many of these techniques are laborious and require high‐precision equipment. Thus, the development of new techniques can optimize the evaluation of sperm DNA damage. Therefore, the aim of this study was to standardize the toluidine blue (TB) stain technique for the analysis of DNA fragmentation of dog, cat, bull, stallion and ram spermatozoa. For this purpose, we used six animals of each specie (n = 30), in reproductive age. Sperm was collected by different methods according to the particularities of each species, and such samples were divided into two aliquots: a sperm sample was kept at 5°C (considered as intact sperm DNA), and the remaining samples were submitted to the induction of DNA fragmentation by exposure to ultraviolet light for 4 hr. Samples were then mixed with the intact sample to obtain known and progressive proportions of sperm with fragmented DNA (0%, 25%, 50%, 75% and 100%). Semen smears were performed and subjected to staining with TB. Blue‐stained spermatozoa were considered to have DNA fragmentation. We observed high linear regression coefficients between the expected proportion of damaged DNA and the results of TB for dog, cat, ram, bull and stallion samples. In conclusion, TB stain was considered a fast and effective technique for the study of spermatozoa DNA in several species. 相似文献
3.
4.
Agreement of high definition oscillometry with direct arterial blood pressure measurement at different blood pressure ranges in horses under general anaesthesia 下载免费PDF全文
ObjectiveTo determine the agreement of high definition oscillometry (HDO) with direct arterial blood pressure measurements in normotensive, hypotensive and hypertensive horses during general anaesthesia.Study designExperimental study.AnimalsSeven healthy warmblood horses, aged 3–11 years, weighing 470–565 kg.MethodsMeasurements from a HDO device with the cuff placed around the base of the tail were compared with pressures measured invasively from the facial artery. High blood pressures were induced by intravenous (IV) administration of dobutamine (5 μg kg−1 minute−1) over ten minutes followed by norepinephrine (0.1 mg kg−1 IV) and low pressures by increasing the inspired fraction of isoflurane and administration of nitroglycerine (0.05 mg kg−1 IV). For analysis three pressure levels were determined: high (MAP>110 mmHg), normal (60 mmHg
5.
The effect of footrot on body weight and wool growth of sheep 总被引:1,自引:0,他引:1
Body weight and traits associated with production of wool were measured over a 2-year period between 1985 and 1987 in south-western New South Wales in a flock of Merino wethers experimentally infected with footrot. The disease was allowed to spread freely amongst 150 of the flock but kept at very low prevalence in the remaining 50 by preventive footbathing during transmission periods. Severe, underrunning footrot had a significant adverse effect on body weight, for each year of the trial. Body weight was most severely reduced at times of the year when footrot was spreading among animals and lesions were severe. The mean body weight of the infected group at the end of the 2 years of observation was 7.3 kg (11.6%) below that of the control group. Footrot also depressed wool growth, with the mean clean fleece weight of the infected group being 0.4 kg (8%) lighter than that of the controls at each of the 2 annual shearings. There were no consistent differences between the groups for the other wool characteristics measured. 相似文献
6.
Variation in seed production and its components was investigated between and within four cultivars of the pasture grass Setaria
sphacelata, in two experiments over two years, as a basis for future cultivar improvement. The study sought to determine the
basis for the considerable differences in seed production of the four cultivars Nandi, Narok, Solander and Kazungula, to determine
the extent of genetic variation in the four cultivars in attributes which contribute to seed yield, and to investigate genotypic
consistency in seed production over years and seasons. Each experiment comprised 50 genotypes of each cultivar. In the first
experiment, plants were harvested a set number of days after median flowering date whereas in the second experiment, which
was unreplicated, each genotype was harvested a set number of days after it had flowered. In the first experiment, seed yields
were generally highest for Kazungula, lowest for Narok and intermediate for Nandi and Solander. All measured attributes contributing
to seed yield exhibited a high order of variation between and within cultivars, but the basis for the large difference in
seed yield per plant between cultivars was tiller fertility rather that total tiller number. Averaged over the four harvests,
there was a six fold to > 100–fold intra-cultivar genetic range in seed production, associated with differences in tiller
fertility, which were associated with differences in date of first flowering. Broad sense heritability for seed yield averaged
0.68 for the four cultivars and showed little change over the four harvests. Genotypes which produced high seed yields in
summer were also more productive of seed in autumn and the 0ore productive genotypes in the first year were also more productive
in the second year. Cultivars differed in the relative importance of factors which contributed to the high seed yield of high-yielding
genotypes. In the second experiment, genotypes with a high seed yield also generally had the highest tiller fertility, even
though all genotypes were harvested the same number of days after first flowering. Within-cultivar correlations in seed yield
between the two experiments were generally significant and the elite 20% of genotypes from this experiment had 1.2–2.9 times
the seed yield of the same genotypes with a very different harvesting regime in the first experiment. It is concluded that
opportunities exist in all four cultivars for improvement in seed production and that the selection criterion offering the
best opportunity for advance would be fertile tiller number. In Narok, Solander and Nandi, this would result in increased
tiller fertility, whereas in Kazungula, it would result in an increase in total tiller number.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献
7.
D V Hacker N C Buyukmihci C E Franti R W Bellhorn 《American journal of veterinary research》1987,48(2):320-322
The mydriatic effect of 10% phenylephrine was evaluated in 9 horses. Base-line pupillary size in mesopic conditions and during light stimulation was ascertained before application of pharmacologic agents. In study 1, 10% phenylephrine was applied to each eye (n = 5 horses). After 15 minutes, the pupillary size was determined in both lighting conditions. Phenylephrine was again applied to each eye, and after an additional 15 minutes, the pupillary size was determined. In study 2, 1% tropicamide was applied to each eye (n = 4 horses), and after 30 minutes, the pupillary size was determined in both lighting conditions. Tropicamide and phenylephrine were applied to each eye immediately after determination of pupillary size, and after an additional 30 minutes, the pupillary size was determined. There was no significant change (P greater than 0.9) in pupillary size when phenylephrine was used alone or when phenylephrine was used in an eye that had been dilated with tropicamide. 相似文献
8.
Ocular angiosarcoma in four horses 总被引:2,自引:0,他引:2
D V Hacker P F Moore N C Buyukmihci 《Journal of the American Veterinary Medical Association》1986,189(2):200-203
In 4 horses with ocular angiosarcomas, the common characteristics were that all horses were aged, and the neoplasms developed initially on conjunctival surfaces, grew slowly, and metastasized despite excision and radiation treatment. Histopathologically, the neoplasms were of 2 types: a capillary pattern of scant stroma and endothelial-lined vascular channels, and a solid pattern composed of sheets of pleomorphic cells with hyperchromatic nuclei and poorly defined cytoplasmic borders. Definitive diagnosis was made by use of factor VIII:RAg, which stained the tissues intensely. 相似文献
9.
Liza Wittenberg-Voges Sabine BR. Kästner Marja Raekallio Outi M. Vainio Karl Rohn Klaus Hopster 《Veterinary anaesthesia and analgesia》2018,45(2):165-174
Objective
To compare the effects of MK-467 during isoflurane anaesthesia combined with xylazine or dexmedetomidine on global and gastrointestinal perfusion parameters.Study design
Prospective, randomized experimental trial.Animals
A total of 15 warmblood horses.Methods
Horses were divided into two groups for administration of either dexmedetomidine (D) or xylazine (X) for premedication (D: 3.5 μg kg?1; X: 0.5 mg kg?1) and as constant rate infusion during isoflurane anaesthesia (D: 7 μg kg?1 hour?1; X: 1 mg kg?1 hour?1). During anaesthesia, heart rate, mean arterial blood pressure (MAP), systemic vascular resistance index (SVRI) and cardiac index (CI) were measured. Microperfusion of the colon, jejunum and stomach was measured using laser Doppler flowmetry. After 2 hours of stabilization, MK-467 (250 μg kg?1) was administered, and measurements were continued for another 90 minutes. For statistical analysis, the permutation test and Wilcoxon rank-sum test were used (p < 0.05).Results
There were no differences in baseline measurements between groups. The MK-467 bolus resulted in a significant decrease in MAP (D: –58%; X: –48%) and SVRI (D: –68%; X: –65%) lasting longer in group D (90 minutes) compared to group X (60 minutes). While CI increased (D: +31%; X: +35%), microperfusion was reduced in the colon (D: –44%; X: –34%), jejunum (D: –26%; X: –33%) and stomach (D: –37%; X: –35%).Conclusions and clinical relevance
Alpha-2-agonist induced vasoconstriction was reversed by the MK-467 dose used, resulting in hypotension and rise in CI. Gastrointestinal microperfusion decreased, probably as a result of insufficient perfusion pressure. An infusion rate for MK-467 as well as an ideal agonist/antagonist ratio should be determined. 相似文献10.