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Commercially available OptiXcell® extender was compared with conventional extenders for freezability and in vivo fertility of bull semen. Semen was collected from three Friesian bulls for five weeks (replicate) and qualifying ejaculates (motility >60%, concentration >0.5 billion/mL, volume >lmL) were diluted (37°C; 50 x 10⁶ spermatozoa/ml) with OptiXcell®, tris-citric egg yolk and egg yolk-citrate extenders. Diluted semen was cooled to 4°C in 2 hours, equilibrated for 4 hours and filled in 0.5 ml straws. The straws were kept over liquid nitrogen vapours for 10 minutes and plunged into liquid nitrogen. Percentages of post thaw sperm motility and plasma membrane integrity were recorded higher (P<0.05) in OptiXcell® compared to tris-citric egg yolk followed by egg yolk-citrate extender. Sperm viability (%) were recorded higher (P<0.05) in OptiXcell® compared to tris-citric egg yolk and egg yolk citrate extender. Percentages of normal apical ridge and DNA integrity were higher (P<0.05) in OptiXcell® and tris-citric egg yolk extender compared to egg yolk-citrate extender. Higher (P<0.05) fertility rate was recorded with semen frozen in OptiXcell® compared to triscitric egg yolk and egg yolk-citrate extender. In conclusion, OptiXcell® is superior to conventional extenders for spermatozoa) quality of frozen-thawed bull semen and produced higher fertility rates under field conditions.
Breeding of (outbred) selective lines of laboratory mouse was initiated in Warsaw University of Life Sciences about 40 years ago. It bred Heavy (C) and Light (L) mice selected opposite for body weight at weaning (21st day of life), S mice line selected for higher testes weight, and control (K) mice without selection. All lines have identical genetic background, but different directions of selections caused diversification of specific phe-notypic traits between them. The purpose of this study was to compare semen quantity and quality parameters in outbred C, K, L and S male mice in the context of measurements of average body and testes weight for each line. Research materials were seminal fluids squeezed out of the vas deferens from 20 outbred C, K, L and S male mice (5 males per group). Animals had been euthanized, and necropsy was performed. Body and testes weight was measured. Also sperm concentration, viability (by Eosin test), cytoplasmic membrane integrity degree (HOS test), sperm head morphology and maturity were estimated. It was shown that S male mice, which have much higher testes weight, also have a significant increase of viable spermatozoa according to control line. Moreover, sperm concentration from S males is at least two times higher than in other selective lines.
The study was conducted to evaluate the effect of addition of L-cysteine to tris-citric acid (TCA) extender on the post-thaw quality of Sahiwal bull semen. For this purpose, two consecutive ejaculates were collected from three Sahiwal bulls using artificial vagina at weekly intervals for a period of three weeks (three replicates). Qualifying semen ejaculates were diluted (50×106 motile spermatozoa ml-1) in TCA extender having L-cysteine either 0.0 (control) or 0.5, 1.0 or 2.0 mM. Diluted semen was cooled to 4°C for 2 h, equilibrated for 4 h at 4°C, filled in straws at 4°C, kept in liquid nitrogen vapours for 10 min and then stored in the liquid nitrogen. Thawing was performed after 24 h of storage, at 37°C for 30 s. and the sperm motility, viability, plasma membrane and acrosomal integrity were assessed. Higher (P<0.05) sperm motility, viability, plasma membrane and acrosomal integrity were observed using extenders containing 1.0 or 2.0 mM compared to those containing 0.5 or 0.0 mM L-cysteine. It is concluded that addition of L-cysteine (to reach 1.0-2.0 mM) in TCA extender improves the post-thaw quality of Sahiwal bull semen.
This work aimed to establish correlation between concentration of zinc, copper and calcium in seminal plasma and characteristics of semen of stallions of various breeds (Thoroughbred -TB, Great Polish Horses -GPH, Polish Primitive Horses -PPH) and aged (≤ 11 years, > 11 years, > 14 years ). Measurements revealed interbreed differences in the concentration of zinc (TB:GPH, TB:PPH), copper (PPH:TB) and calcium (GPH:TB) in the seminal plasma of stallions. No age-dependent alterations in the element concentrations of plasma were found in stallions. There was a significantly (P<0.05) positive correlation between zinc and copper concentrations in the seminal plasma (PPH) and a positive correlation between selected characteristics of stallion semen, especially between zinc and concentration of spermatozoa, (GPH, PPH, stallions ≤ 11 years of age, > 11 years, all stallions), between calcium and spermatozoa with secondary changes (GPH, stallions ≤ 11 years of age, all stallions) and also a negative correlation between copper concentration and motile- and live spermatozoa (TB, GPH, stallions > 11 years of age, all stallions).
The aim of this study was to determine the effects of two dietary protein levels on testosterone, testicular parameters and semen quality in Kivircik ram lambs during pubertal development. Two experimental groups were formed. Following weaning, crude protein (CP) and metabolic energy (ME) levels were 12% CP, 2.54 Mcal/kg in group I (low protein diet) and 18% CP, 2.52 Mcal/kg in group II (high protein diet). Measurements of live weight and testicular characteristics and collection of blood samples for testosterone hormone concentrations were performed at 20 day intervals starting from 115-days- up to 195-days-of-age. There was an increase in semen volume, spermatozoa concentration and the percentage of progressively motile sperm in both groups between 135 and 195 days of age. Group I had significantly higher semen volume on day 175 (P < 0.05). Furthermore, spermatozoa concentrations were higher in group I than those in group II on days 155 and 175 (P < 0.05). Values of live weight, testicular diameter, testicular circumference, testicular length and testicular volume of ram lambs in group II (high protein diet) were higher than those in group I (low protein diet). Testicular length and testicular volume of group II were significantly higher than those of group I on day 195 (P < 0.05). Despite the fact that group II had an alternating testosterone hormone concentration, it was determined that Group II had better testosterone hormone concentration values than group I on day 115, 135 and 175. However, group I had a higher testosterone hormone level on day 155 and 195. Live weight and testicular characteristics of ram lambs fed with a high protein diet were affected positively during pubertal development. However, it was observed that feeding with a high protein diet had a negative effect on semen characteristics by impairing the thermoregulation mechanism and spermatogenesis in testicles because of excessive fat accumulation in the scrotum.
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