Czech Journal of Animal Science, 2008 (vol. 53), issue 7

Comparison of different traits to evaluate the growth of bulls

J. Přibyl, J. Přibylová, H. Krejčová, N. Mielenz

Czech J. Anim. Sci., 2008, 53(7):273-283 | DOI: 10.17221/357-CJAS  

The live weights of 8 243 performance-tested bulls from 100 to 400 days of age were analysed using random regression (RR) and single-trait animal models. Evaluations were done for live weight at 400 days of age and gains from 100 to 400 days of age at various monthly intervals. Estimates of variance components differed depending on the trait definition and model of analysis. Systematic environmental effects explained a higher proportion of variability in the RR for gains than for other definitions of growth. The expected average reliability of estimated breeding values was similar for all methods from 0.42 to 46, but the rankings of animals differed....

Analysis of non-genetic factors affecting calving difficulty in the Czech Holstein population

M. Fiedlerová, D. Řehák, M. Vacek, J. Volek, J. Fiedler, P. Šimeček, O. Mašata, F. Jílek

Czech J. Anim. Sci., 2008, 53(7):284-291 | DOI: 10.17221/355-CJAS  

The objective of this study was to analyze the effects of non-genetic factors affecting calving difficulty in the Holstein population of the Czech Republic for subsequent compilation of the model for genetic evaluation as well as for herd management practice. Calving difficulty recorded in 1997-2006 was assessed in three categories: 1 = normal, 2 = hard pull, 3 = complicated. The original observations were transformed to an underlying normal scale. A data set containing 409 255 records was analysed by a linear model with fixed effects of season, parity of dam, sex of calf and Holstein gene proportion. All these effects were significant, and their appropriate...

Activity of glutathione peroxidase (GSH-Px) in the blood of ewes and their lambs receiving the selenium-enriched unicellular alga Chlorella

J. Trávníček, J. Racek, L. Trefil, H. Rodinová, V. Kroupová, J. Illek, J. Doucha, L. Písek

Czech J. Anim. Sci., 2008, 53(7):292-298 | DOI: 10.17221/354-CJAS  

The effect of supplementation of selenium inorganic and organic forms on the activity of glutathione peroxidase (GSH-Px) was investigated for 7-8 months in three groups of ewes (by five animals each) and in born lambs. The basal feed ration contained 55 μg Se, the ewes of experimental group E1 received a supplement of 180 μg Se in sodium selenite, and the ewes of experimental group E2 were administered a supplement of 180 μg selenium bound in the biomass of the alga Chlorella. Control group C was without selenium supplement. The ewes were in the stage of non-pregnancy, pregnancy and lactation during the experiment. The average number...

Influence of n-3 and n-6 polyunsaturated fatty acids on sensory characteristics of chicken meat

J. Zelenka, A. Jarošová, D. Schneiderová

Czech J. Anim. Sci., 2008, 53(7):299-305 | DOI: 10.17221/356-CJAS  

The relationship between different levels of n-6 and n-3 PUFA in chicken breast and thigh meat and sensory characteristics of meat was studied. Chickens were fed diets containing 1, 3, 5 or 7 percent of oil made of seeds either of the linseed cultivar Atalante (A) with a high content of α-linolenic acid or of the cultivar Lola (L) with a predominating content of linoleic acid. The meat of chickens fed L showed better sensory characteristics than the meat of birds fed A. If the tissue contained more than 180 mg/100 g of n-3 PUFA, i.e. the thigh meat when chickens were fed 3% or more A and the breast meat when chickens were fed 7% A, significant...

Effect of dietary selenium on lipid oxidation, selenium and vitamin E content in the meat of broiler chickens

M. Skřivan, G. Dlouhá, O. Mašata, S. Ševčíková

Czech J. Anim. Sci., 2008, 53(7):306-311 | DOI: 10.17221/358-CJAS  

An experiment was conducted to compare the effect of dietary sodium selenite and selenomethionine on selenium and α-tocopherol concentration in breast meat, oxidative stability of meat in broilers, and on growth performance, but only as an unimportant criterion in this case. Sexed broiler cockerels Ross 308 were allocated to 3 dietary treatments, each comprising 100 chickens. The basal diet was supplemented with 0 (control) or 0.3 mg/kg Se from sodium selenite (SS) or selenomethionine (SM). Dietary supplementation with SM increased (P < 0.05) body weight, but only by about 3%. Breast muscle Se concentration was increased (P <...