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The objective of this study was to optimize recovery and cryopreservation of epididymal sperm from plains bison, as a model for wood bison. In Phase 1, cauda epididymides were recovered from bison (n = 14) immediately after slaughter, minced and incubated in Sp-TALPH buffer for 3 h at 36°C. The resulting sperm suspensions were cryopreserved in Triladyl® , using a protocol for bovine semen. In Phase 2, epididymal sperm were cryopreserved in either Triladyl® or Andromed® . The mean (±SD) estimated number of sperm recovered was 468 ± 207 × 106 . There was an increase (p < 0.05) in the proportion of sperm with normal morphology between initial recovery and after extension (52.4 ± 4.6 vs 69.7 ± 2.4%), with a concurrent decrease (p < 0.05) in the proportion of sperm with distal droplets. Median values for progressively motile sperm in post-thaw samples (60%) were lower (p < 0.05) than that after extension or after chilling (70% for both). The mean percentages of viable sperm and of sperm with an intact acrosome were lower (p < 0.05) for frozen-thawed samples (38.7 ± 2.8 and 85.2 ± 1.1) compared with extended (66.2 ± 2.2 and 92.4 ± 0.9) or chilled (63.7 ± 2.5 and 90.0 ± 1.0) samples. Rates of cleavage, morulae and blastocyst production were not significantly different for chilled (70.9, 38.7 and 8.0%) vs post-thaw sperm (73.0, 46.0 and 6.3%). There was no significant difference between extenders for most sperm characteristics. In conclusion, we developed a functional protocol for the recovery and cryopreservation of epididymal sperm from plains bison, which may have implications for the genetic preservation of wood bison. 相似文献
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Double-outlet right ventricle in a 10-month-old Friesian filly 总被引：1，自引：1，他引：0
LC Fennell S Church D Tyrell G Forbes JA Charles C McCowan CJ Savage 《Australian veterinary journal》2009,87(5):204-209
A 10-month-old Friesian filly had a presentation that was consistent with chronic left- and right-sided congestive heart failure. Clinical pathology findings included abnormal haematological and biochemical variables, abnormal blood gas values and increased serum concentration of cardiac troponin I. Echocardiography revealed cardiac chamber dilation and dextropositioning of the aorta. Radiography revealed a generally enlarged heart and pulmonary interstitial infiltration. These findings were supported at necropsy and the diagnosis of double-outlet right ventricle was confirmed. The pathological changes and physiological responses subsequent to double-outlet right ventricle have not previously been described in detail in horses. Clinical progression closely resembles that seen in humans, in whom antemortem diagnosis relies on echocardiography. In horses, complex cardiac disease presents a diagnostic challenge to the clinician. Appropriate therapy must be based on an accurate diagnosis. 相似文献
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This paper describes the pathologic features of a natural infection by Babesia bovis (B. argentina) in Brazil. Microscopic examination of cerebrum, midbrain, cerebellum, liver, kidney, heart and spleen of five fatal cases revealed variable degrees of congestion, particularly in the brain, liver and kidney. The packing of erythrocytes, the majority of which were parasitized, was most marked in the capillaries of brain, kidney and less in liver. Lymphocytic glomerulonephritis was observed. Variable degrees of fatty degeneration were noted in the liver, distention of hepatic canaliculi and biliary retention was marked. A strong activation of the mononuclear phagocytic system was evident in all the subjects studied. 相似文献
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Co‐Expression of c‐Fos with Oestradiol Receptor α or Somatostatin in the Arcuate Nucleus,Ventromedial Nucleus and Medial Preoptic Area in the Follicular Phase of Intact Ewes: Alteration after Insulin‐Induced Hypoglycaemia 
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Álvaro José de Almeida Bicudo Ricardo Yuji Sado & José Eurico Possebon Cyrino 《Aquaculture Research》2009,40(4):486-495
Haematopoiesis and blood cells' functions can be influenced by dietary concentration of nutrients. This paper studied the effects of dietary protein:energy ratio on the growth and haematology of pacu, Piaractus mesopotamicus . Fingerling pacu (15.5±0.4 g) were fed twice a day for 10 weeks until apparent saciety with diets containing 220, 260, 300, 340 or 380 g kg−1 crude protein (CP) and 10.88, 11.72, 12.55, 13.39, 14.22 MJ kg−1 digestible energy (DE) in a totally randomized experimental design, 5 × 5 factorial scheme ( n =3). Weight gain and specific growth rate were affected ( P <0.05) by protein level only. Protein efficiency ratio decreased ( P <0.05) with increasing dietary protein at all levels of dietary energy. Daily feed intake decreased ( P <0.05) with increasing dietary energy. Mean corpuscular haemoglobin concentration was affected ( P <0.05) by DE and interaction between dietary CP and DE. Total plasma protein increased ( P <0.05) with dietary protein and energy levels. Plasma glucose decreased ( P <0.05) with increasing dietary protein. The CP requirement and optimum protein:energy ratio for weight gain of pacu fingerlings, determined using broken-line model, were 271 g kg−1 and 22.18 g CP MJ−1 DE respectively. All dietary CP and DE levels studied did not pose damages to fish health. 相似文献
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RE Green BFS Santos CC Sicherle FC Landim-Alvarenga SD Bicudo 《Reproduction in domestic animals》2009,44(3):406-410
The aim of this study was to evaluate the viability in the effect of open pulled straw (OPS) vitrification procedure of sheep embryos after direct transference. Embryos were produced in vivo and cryopreserved in slow freezing or OPS vitrification. The survival rates of cryopreserved embryos were compared to non-frozen standard pattern. In a first set of experiments, embryos at morula and blastocyst stages were dived in ethylene glycol (1.5 M) and frozen in an automatic freezer. After being thawed, they were directly or indirectly transferred to ewes recipient. A second group of embryos were drawn into OPS and plunged into liquid nitrogen after being exposed at room temperature for 1 min and 45 s in 10% EG plus 10% dimethyl sulphoxide (DMSO), then again for 30 s in 20% EG + 20% DMSO + 0.5 M sucrose. After being warmed, embryos were also directly transferred using a French mini straw as the catheter for the transplantation process or after in vitro dilution of cryoprotectants (two-step-process). No significant difference was observed among fresh, frozen or vitrified embryos on pregnancy rate (50.0%, 38.6% and 55.8%). However, when we evaluated only the direct transference, the pregnancy rate of OPS vitrified embryos was higher than that of frozen embryos (57.1% vs 34.8%) (p = 0.07). In addition, vitrified morulae had a higher pregnancy rate than the one with frozen embryos (64.0% vs 38.9%) (p = 0.07). Finally, our results indicate that OPS vitrification technique in association with direct transference improves the viability of sheep embryos with potential applications to field conditions. 相似文献
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Objective To evaluate the reproductive efficiency of horse farms in north-east Victoria and identify aspects of management to be targeted for improving reproductive efficiency. Design Retrospective study. Procedure Records from seven Thoroughbred (TB) and four Standardbred (STB) studs in north-east Victoria from 1990 to 2001 were reviewed; 8813 cycles in 4455 mares were analysed. TB mares were inseminated by natural mating, whereas STB mares (89%) were artificially inseminated. Results The overall early pregnancy rate per cycle was 68.8% for TB mares and for STB mares, 68.3%. Multiple pregnancy per cycle was more frequent in TB (8.3%) than in STB (4.6%) mares (P < 0.001). Early embryonic death occurred in 7.1% of TB and 7.5% of STB pregnancies. TB mares had fewer inseminations per cycle (1.03) than STB mares (1.43) (P < 0.001). There was a significantly lower proportion of barren reproductive status within the TB than the STB mares. Pregnancy rate per cycle among stallions ranged from 48% to 79%. Conclusions On-farm pregnancy rates in both breeds were higher than previously reported and likely reflect improvements in reproductive management. The disparity between breeds in the inseminations per cycle and proportion of barren mares exposed the differing structures of the two industries, and presents a target for improving the reproductive efficiency in STBs. The difference between breeds in the multiple pregnancy rate per cycle likely reflects the higher ovulation rate of TB mares. The variability in pregnancy rate per cycle between the 22 stallions was associated with differences in individual inherent fertility and the quality of stallion management. 相似文献
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LC Venema JWG Wildoer JW Janssen SJ Tans HLJT Tuinstra LP Kouwenhoven C Dekker 《Science (New York, N.Y.)》1999,283(5398):52-55
Carbon nanotubes provide a unique system for studying one-dimensional quantization phenomena. Scanning tunneling microscopy was used to observe the electronic wave functions that correspond to quantized energy levels in short metallic carbon nanotubes. Discrete electron waves were apparent from periodic oscillations in the differential conductance as a function of the position along the tube axis, with a period that differed from that of the atomic lattice. Wave functions could be observed for several electron states at adjacent discrete energies. The measured wavelengths are in good agreement with the calculated Fermi wavelength for armchair nanotubes. 相似文献