Czech Journal of Animal Science, 2004 (vol. 49), issue 8

Differences between metabolic profiles of egg-type and meat-type hybrid hens

P. Suchý, E. Straková, B. Jarka, J. Thiemel, V. Večerek

Czech J. Anim. Sci., 2004, 49(8):323-328 | DOI: 10.17221/4316-CJAS  

The main objective of this study was to compare the metabolic profile (i.e. selected haematological and biochemical parameters in blood plasma) of production egg-type hybrid hens (E, MORAVIA BSL) with that of meat-type hybrid hens (M, COBB 500), and to evaluate dynamic changes occurring during the laying period from the 25th to 50th week of age. The study was prompted by both poultry farmers and veterinary practitioners since parameters defining the health of layers are absent. Selected parameters of the metabolic profile of layers were monitored regularly in 5-week intervals during egg laying. Samples of blood for haematological and biochemical examination...

Effects of rearing, sire and calving season on growth and milk efficiency in dairy cows

J. Brouček, P. Kišac, A. Hanus, M. Uhrinčať, V. Foltys

Czech J. Anim. Sci., 2004, 49(8):329-339 | DOI: 10.17221/4317-CJAS  

32 primiparous cows were used. We tested the hypotheses that live weight and milk efficiency were influenced by the system of rearing from the second week of life to weaning, by the sire, and by the season of calving. Three groups were created according to a rearing system (A - pens with automatic drinking cups, H - individual huts and N - pens with nursing cows). Primiparous cows originated from four sires and were divided according to the season of calving (spring, summer, autumn and winter). Group N had the highest LW (540.5 kg) and group A the lowest (504.8 kg) in the 1st month of the first lactation. In the 10th month of lactation, the weights...

Lysosomal proteolysis in skeletal muscles of bulls

S. J Rosochacki, T. Sakowski, J. Połoszynowicz, E. Juszczuk-Kubiak, A. Kowalik-Krupa, J. Oprządek

Czech J. Anim. Sci., 2004, 49(8):340-348 | DOI: 10.17221/4318-CJAS  

The relationship between lysosomal proteolytic enzyme activities involved in skeletal muscle proteolysis of the longissimus lumborum et thoracis muscle (MLLT) of bulls was described. Samples from the same region were obtained post mortem from 7 Piemontese (P) and 54 Black-and-White bulls (B-W) about 18 months old fed ad libitum. The activity of cathepsin D was determined as pepstatin (cathepsin D inhibitor) sensitive activity (PSCatD) towards 1% haemoglobin. Pepstatin-insensitive acid (PIA) and leupeptin-insensitive (thiol proteinase inhibitor) acid (LIA) autolytic activities were measured in the presence of 1 mM Mg⁺⁺....

Analysis of alternative models treating herd × year effects as fixed or random

I. Nagy, J. Sölkner, L. Csató, J. Farkas, L. Radnóczi

Czech J. Anim. Sci., 2004, 49(8):349-356 | DOI: 10.17221/4319-CJAS  

The analysis was conducted of the national database of station tests carried out between May 1996- February 2001, using the Hungarian Large White breed. Days of test, total amount of consumed feed and valuable cuts were taken into the analysis. Using the method of cross validation, small subsets of the data were excluded and then predicted using the remaining part of the data treating herd × year effects either as fixed or as random. The size of the data excluded was 50 or 10 records at a time and the process was repeated 100 or 500 times, respectively. Mean squared error, bias and correlation between the excluded and predicted observations were calculated...

Main sources of the economic efficiency of beef cattle production systems

M. Wolfová, J. Wolf, R. Zahrádková, J. Přibyl, J. Daňo, J. Kica

Czech J. Anim. Sci., 2004, 49(8):357-372 | DOI: 10.17221/4320-CJAS  

The economic efficiency of several beef production systems on pasture was investigated under different marketing strategies. All calculations were carried out with the computer program ECOWEIGHT. None of the considered production systems was profitable without government subsidies for the assumed economic input values. The subsidies granted when satisfying a set of conditions served for balancing the economic loss in systems selling all surplus weaned calves outside. A profitability of 10 to 25% was reached for this marketing strategy in dependence on the production system. When integrating feedlot, only the purebred system with mating female replacement...