Czech Journal of Animal Science, 2009 (vol. 54), issue 5

Relationships between milk urea and production and fertility traits in Holstein dairy herds in the Czech Republic

D. Řehák, R. Rajmon, M. Kubešová, M. Štípková, J. Volek, F. Jílek

Czech J. Anim. Sci., 2009, 54(5):193-200 | DOI: 10.17221/1664-CJAS  

The objective of this study was to determine how the concentration of milk urea (MU) and FPCM production affect reproduction in selected Holstein dairy herds in the Czech Republic. A retrospective, observational study comprising analyses of individual cow records from monthly dairy herd improvement (DHI) milk tests including milk urea (MU) concentration was conducted in six commercial Holstein dairy herds in cows that were bred from July 2000 to August 2003. A total of 1 333 cows with available breeding date, pregnancy status, and calving to first service interval from 31 to 150 days were selected. The data were evaluated using the mixed linear model...

Changes in fatty acid profile and iodine content in milk as influenced by the inclusion of extruded rapeseed cake in the diet of dairy cows

A. Veselý, L. Křížová, J. Třináctý, S. Hadrová, M. Navrátilová, I. Herzig, M. Fišera

Czech J. Anim. Sci., 2009, 54(5):201-209 | DOI: 10.17221/1721-CJAS  

The aim of the study was to evaluate the effect of extruded rapeseed cake in diets of dairy cows on changes in milk fatty acid profile and iodine content in milk and on the thyroid gland status. An experiment was carried out on four lactating Holstein cows divided into 2 groups - experimental (R) fed a diet based on extruded rapeseed cake and control (S) fed a diet based on extruded full-fat soya. The experiment was divided into 4 periods of 42 days (21 days of preliminary period and 21 days of experimental period). Samples of milk and blood were taken three times a week during the experimental period. DMI was not affected by the treatment (P...

Missense mutations in exon 2 of the porcine leptin receptor gene and their associations with litter size and body weight

C. Sun, L. Wang, D. F. Jiang, B. Zhang

Czech J. Anim. Sci., 2009, 54(5):210-216 | DOI: 10.17221/1663-CJAS  

Leptin receptor (LEPR) gene is regarded as a "candidate-gene" of production traits. The aims of this study were to detect polymorphisms of exon 2 within LEPR gene and to investigate their associations with production traits, litter size and live weight in Luchuan and Large White pig breeds. For this purpose, the single nucleotide polymorphisms (SNPs) of exon 2 within LEPR were detected using the PCR-SSCP procedure and their association with litter size and live weight was also analysed in Luchuan (n = 446) and Large White pigs (n = 405). The results showed that the C155T mutation was found in exon 2 of porcine LEPR...

Results of pig carcass classification according to SEUROP in the Czech Republic

J. Kvapilík, J. Přibyl, Z. Růžička, D. Řehák

Czech J. Anim. Sci., 2009, 54(5):217-228 | DOI: 10.17221/1662-CJAS  

Through data analysis of 7 571 883 pig carcasses slaughtered from 2004 to 2007 the means of quality classes (QC) 2.32, lean meat percentage (LM) 55.83%, carcass weight (CW) 87.21 kg, muscle thickness (MT) 61.95 mm and fat thickness (FT) 15.95 mm were determined. The highest correlation coefficients are between QC and LM (r = -0.920), LM and FT (-0.900) as well as QC and FT (0.828), the lowest between FT and MT (r = -0.084). Quality class as the dominant indicator is influenced mainly by LM, which explains from 77% to 89% of variability in the case of linear regression. Among the eight methods of pig carcass classification the FOM apparatus...

Effect of microbial oil and fish oil on rumen fermentation and metabolism of fatty acids in artificial rumen

D. Jalč, M. Čertík, K. Kundríková, P. Kubelková

Czech J. Anim. Sci., 2009, 54(5):229-237 | DOI: 10.17221/1765-CJAS  

The objective of this study was to examine the effect of microbial oil (MO, n-6 fatty acids) and fish oil (FO, n-3fatty acids) used in their blends as supplements (5% wt/wt) to the diet containing 80% of hay and 20% of barley on rumen fermentation and lipid metabolism in artificial rumen. Overall, three different ratios of n-6 and n-3 fatty acids (1:1, 3:1, and 5:1) as the blends of MO and FO were used. Two similar consecutive experiments were carried out within 2 months. Each experiment lasted for 12 days with 6 days of stabilization period. The addition of all three oil blends did not affect the parameters of fermentation such as degradation of dry...