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Mammal spermatozoa demonstrate a wide morphologic variety resulting from the different histories of their genetic development. Alongside a general sperm classification including a head and tail there are significant differences between shape and size of head and length of tail between particular species. Regarding species peculiarity, the differences in the sperm can be determined not only with the quantity of genetic material in testicles possessing a particular shape and different grade of flattening, but also with: size, grade of acrosom diversity and other morphometric features of the remaining gamete parts: the neck and midpiece. During sperm morphology estimation it is crucial to consider the breeding season of particular species, because the quality of semen in moderate and cool climate animals is strongly influenced by the length of the day. While studying semen characteristics for particular species of wild animals, on account of differences in processes of spermatogenesis determined by a variety of factors, in the majority of cases the useful spermiograms for domestic animals cannot be applied.
The respective investigations were carried out at the Experiment Station Popielno, Polish Academy of Sciences on crosses heifer-calves and bull-callves of the genotypes of 50% Hereford, 25% black-and-white, 25% bison (16 heads) as well as 50% Charolais, 25% black-and-white and 25% bison (13 heads). The bull-calves were subjected to the control fattening from the 13th week of life to reaching the weight of 450 kg. It has been proved that cross bull-calves after bison x black-and-white dams with black-and-white x Hereford sires were significantly heavier at birth than their counterparts after Charolais sires. In later periods till the slaughter, no significant differences between both types of crosses in such traits, as body weight gains, carcass dressing, share of basic tissues in sides were found. Thus it may be concluded that both beef breeds can be successfully used for mating with F₁ crosses.
Cryopreservation of red deer sperm is essential for establishing the biodiversity of this species. The aim of the study was to test four extenders and two freezing methods on the cryosurvival of red deer spermatozoa. Semen collected with an artificial vagina from 4 stags was diluted with compared extenders: A (citrate- -fructose-egg yolk-glicerol), B (Tris-fructose-citric acid-egg yolk-glicerol), C (Triladyl® with egg yolk) and D (Bioxcell®). Sperm, loaded into 0.25 ml straws, was frozen in nitrogen vapor (method L) and in the Minicool 40 PC (method M) cryogenic unit. After thawing the motility of spermatozoa was evaluated subjectively. Viability was assessed using nigrosin-eosin (N-E test), SYBR-14 with propidium iodide (L/D test) and hypoosmotic swelling test (test HOS) to detect membrane integrity. The best post-thaw motility was obtained with the use of extender D (43.0 ± 14.2%). Similarly, more viable spermatozoa (p < 0.05) at N-E and L/D tests (42.4 ± 11.3% and 39.9 ± 14.0% respectively) were preserved in extender D. The lowest results in those tests were received in extender A. The percentage of HOST-responsive spermatozoa was higher (p < 0.05) in method M than in L (19.8 ± 9.8 % vs 14.3 ± 7.6 %), independently of the utilized extenders. In conclusion, the use of extender D in combination with freezing method M significantly improved freezability of red deer spermatozoa.
Autorzy prezentują wyniki badań dotyczące zawartości Cu, Zn, Pb i Cd w mięśniu piersiowym i wątrobie krzyżówek pozyskanych na Warmii i Mazurach w roku 2004. Analizowano próbki z 64 kaczek upolowanych w 8 różnych miejscowościach województwa warmińsko-mazurskiego. Stężenie Cd, Zn i Cu było większe w wątrobie niż mięśniu piersiowym. Zawartości metali ciężkich u krzyżówek pozyskanych na Warmii i Mazurach są porównywalne z ich analogami u ptaków fermowych i przyzagrodowych oraz nie zagrażają zdrowiu ewentualnych konsumentów. W porównaniu do innych obszarów Polski, Europy i Ameryki Północnej, świadczą jednocześnie o małym zanieczyszczeniu środowiska tego regionu Polski (ekspozycja na poziomie tła środowiskowego).
The material for this study was obtained from culled European bison (Linnaeus, 1758) originating from both captive breeding and free-ranging populations in Białowieża and Borecka Forests (north-east Poland), and was mostly collected from November until April. Mass difference between the right and left testis of the same individual up to 30% was considered to be physiological asymmetry, which proved typical of the species. Hypoplasia or atrophy of the testes exceeding 30% in size, were found in 37 males (13.6% of the examined animals;n=272). Cryptorchidism was recorded in 20 bison culled in Białowieża Forest at the age over 1 year (10.6% of individuals at the same age;n=188). We registered the weight of testes of 259 males aged 2 months to 20 years. In the examined males, no distinct predominance in size and weight between the right and left testes was observed. The weight of testes was significantly correlated with age (r=0.85,p < 0.0001) and body weight (r=0.93,p < 0.0001). The heaviest testicles belonged to older and sexually mature bulls aged 6–12 years (mean 216 g) and to old ones over 13 years (mean 242 g). Two testis measurements (length and width) were taken from 136 culled males, while two additional measurements (total length with the cauda of epididymis and circumference) from 65 males. The length and width of the testes were moderately correlated with age (r=0.31 andr=0.20,p < 0.01) and highly significantly correlated with testis (r=0.79,p < 0.001) and body weight (r=0.92,p < 0.001).
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