No abstract

Due to continuous single nitrogen fertilization, we hypothesized a built-up deficiency of micronutrients in crops that would limit plant growth and crop quality. In 2-year field experiments using urea-N fertilized grain maize (Zea mays L.), hybrid KWS 2376 at 0, 120 and 240 kg N ha (1 crop uptake of Zn, Mn, Cu and Fe was studied at DC 32, DC 61 and in the grain harvested. Micronutrient contents at DC 32 stage Á 1st node (aboveground phytomass) and DC 61 Á flowering (ear leaf) were all at levels indicative of adequate micronutrient supply to the crop. At both sampling occasions the Fe:Zn and Fe:Mn ratios were adequate implying that Fe did not inhibit the uptake of Zn and Mn. The application of nitrogen increased the Fe content at the 1st sampling in both years; in the second year the same was also the case for the Zn content. Nitrogen nutrition increased the contents of Mn and Fe at the 2nd sampling only in year 2; in the other treatments no changes were observed in the micronutrient contents. Micronutrient correlations in the grain were discovered between Zn and Mn contents and between Fe and Mn contents. In the second year the highest N-rate significantly increased the Fe and Zn content of the grain compared with the lower rates of nitrogen fertilization. Grain yields were not affected by the rate of nitrogen and ranged between 13.65 and 14.34 t ha (1 (1st year) and between 13.68 and 14.18 t ha (1 (2nd year). Nitrogen fertilization did not reduce the content of micronutrients in the plant or grain of maize. It is evident that the continuous single use of N fertilization so far has not resulted in a micronutrient deficiency of the plants limiting the nutrient density of the grain or reducing its quality.

In two-year field experiments, nitrogen (N) in the form of urea (0, 120 and 240 kg N/ha) was applied to grain maize (Zea mays L.) hybrid KWS 2376. The two-year mean content of total grain N at harvest was 1.54%. The highest N dose reduced most of the 17 amino acids (AA) analysed in the grain compared with the other treatments. Possible reasons for this could be an adverse effect on the tricarboxylic acid cycle or deficiency of carbon skeletons for the assimilation of NH 4 + into amides and amino acids. The content of the limiting amino acid lysine was not influenced by N fertilisation, with a mean two-year content of 2.02 mg/g DM. Taking into account the differences in fertilisation, the effect of the year was seen in the maximal accumulation of amino acids serine, proline, methionine, threonine, arginine and lysine. Increasing rates of nitrogen reduced the accumulation of asparagine and glycine, and, on the contrary, increased the accumulation of tyrosine. Nitrogen rates have a significant effect on the maximal accumulation of valine, isoleucine, leucine, phenylalanine, histidine, cysteine and alanine and appeared as early as after the first increased rate of nitrogen (120 kg N/ha).

The effects of inbreeding level on service period (SP) and pregnancy length (PL) were monitored in Holstein and Czech Fleckvieh after the first calving. The levels of inbreeding (F X ) ranged from 1.25 to 25 %. SP and PL of inbred cows were compared with their outbred equals -half-sisters, sharing the same sire (n = 1824) and their first calving happened in the same farm and at the same time (± 3 month). Database with the number of 631 810 animals (year of calving 1985-2004) was used for analyses. Inbred cows were grouped according to F x coefficient (1.5-2.3 %; 3.0-5.0 %; 8.0-12.5 %; 25 %). The GLM with fixed effects (the breed, breeding value of the sire and monitored individual for milk production, year of calving, age at first calving) was applied to all data. The effect of inbreeding depression on SP was more pronounced at higher levels of inbreeding (+2.81; +3.35; +4.53; +8.23 d, respectively according to above mentioned F x groups) but non-significant. Differences in PL (+0.3; +0.32; -0.08 and 1.68 d) were not significant either. Average value of PL for inbred animals was 0.43 d higher. The correlation coefficient was +0.023 for SP and +0.0658 for PL. The F x coefficient increasing by 1 % extends the SP by 0.22 day and PL by 0.063 day. There was a higher variability of SP and PL in inbred cows. The length of calving interval between the first and second lactation is affected more by SP than PL.

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.