No abstract

No abstract

ABSTRACT:A good functional status of cryopreserved boar spermatozoa is very important for successful fertilization of porcine oocytes and in vitro embryo production. The purpose of the study was to evaluate the changes in functional status of boar spermatozoa separated from frozen-thawed semen and capacitated in vitro by caffeine. The effect of acrosome reaction development in spermatozoa on the efficiency of oocyte fertilization has been studied in boars A, B and C. Motile spermatozoa were separated by Percoll gradient, untreated (control) or treated with both 1mM and 2mM caffeine, and capacitated or co-cultured with matured oocytes. The motility, viability, chromatin and acrosome integrity, and fertilizing ability of spermatozoa were assessed. The separation significantly increased (P < 0.05) the percentage of viable spermatozoa in all tested boars and percentages of motile and acrosome intact spermatozoa in boars B and C. The capacitation significantly decreased (P < 0.05) the percentages of viable and motile spermatozoa, but after capacitation, the motility and viability were significantly higher (P < 0.05) for the caffeine-treated spermatozoa than for the untreated controls. A fall in the proportion of acrosome-intact spermatozoa was different for each caffeine concentration and each boar, but in all boars, acrosome reaction progress was faster and, similarly, monospermy and the total efficiency of fertilization were significantly higher (P < 0.01) for the spermatozoa treated with 1mM caffeine than for those treated with 2mM caffeine. It can be concluded that there is a potential relationship between the acrosome reaction progress in frozen-thawed boar spermatozoa and the efficiency of fertilization of porcine oocytes. A faster AR induced in spermatozoa by appropriate caffeine treatment resulted in a higher monospermy rate and total efficiency of fertilization. Thus, it is important to test sires before their semen is used for in vitro embryo production. The faster AR induced by 1mM caffeine was more effective in terms of monospermy and total efficiency of fertilization.

The aim of the present study was focused on analysis of reproductive traits in the painted stork (Mycteria leucocephala). The analysis of partial reproductive traits was intended to complete the knowledge necessary for ensuring reproduction of the painted stork in captivity on the required level. The observation was performed in the Zoo Zlín -Lešná from 2011 to 2014. The eggs were measured and weighed after laying and then in several-day intervals. Other observed traits were hatchability of the eggs, number of raised young birds and their weight after hatching. During whole observation period, a total of 90 eggs of the painted stork were evaluated from 12 parental pairs. The average share of fertilized eggs was 38.9 %. Average length of eggs was 68.57 mm, average width was 46.43 mm and average weight was 79.79 g. Average weight loss of eggs during their incubation was 9.87 g. Average hatchability of all the laid eggs was 27.8 %. Average hatchability of the fertilized eggs was 71.4 %. A total of 23 young painted storks were hatched during the observation period. Their average hatching weight was 57.04 g. The overall number of 11 individuals were raised during the four years of observation.

The efficiency of in vitro embryo production is highly variable amongst individual sires in cattle. To eliminate that this variability is not caused by sperm chromatin damage caused by separation or capacitacion, chromatin integrity was evaluated. Seventeen of AI bulls with good NRRs but variable embryo production efficiency were used. For each bull, motile spermatozoa were separated on a Percoll gradient, resuspended in IVF-TALP medium and capacitated with or incubated without heparin for 6 h. Samples before and after separation and after 3-h and 6-h capacitacion or incubation were evaluated by the Sperm Chromatin Structure Assay (SCSA) and the proportion of sperm with intact chromatin structure was calculated. Based on changes in the non-DFI-sperm proportion, the sires were categorized as DNA-unstable (DNA-us), DNA-stable (DNA-s) and DNA-most stable (DNA-ms) bulls (n=3, n=5 and n=9, respectively). In DNA-us bulls, separation produced a significant increase of the mean non-DFI-sperm proportion (p