Template-Type: ReDIF-Article 1.0 Author-Name: P. Šafus Author-Workplace-Name: Research Institute of Animal Production, Prague-Uhříněves, Czech Republic Author-Name: J. Přibyl Author-Workplace-Name: Research Institute of Animal Production, Prague-Uhříněves, Czech Republic Title: Comparison of long-term selection responses of breeding policy in dairy herds Abstract: Genetic and economic responses to genetic gain were evaluated for these breeding arrangements: single use of bulls under testing; single and repeated use of proved bulls for two years and for three years (in combination with selection intensity 1%, 5% or 10% of the best bulls for the use of proved bulls); negative selection of cows in the herd - 10%, 20% or 30% of animals are discarded from reproduction and the animals are left in the herd and used for breeding by beef bulls; negative selection of first-calvers in the herd - 10%, 20% or 25% of animals are discarded for slaughter; discarding of heifers and purchase of animals with higher breeding value, and embryo transfer - a group of selected recipients accounts for 10%, 20% or 30% of the cows with lover breeding value in the dairy herds. Simulations for single use of breeding arrangements and their consequences over a fifty-year period were carried out for the above models using the gene flow method. Only minimum changes will occur since the 25th year of observation. A comparison of the particular models showed the highest gain of proved bulls selected from 1% of the best bulls whose cumulative genetic gain was 41.558 kg of milk proteins on average per cow for the whole observed period. Single use of bulls under testing in the herd resulted in the second highest cumulative genetic gain. Use of proved bulls selected with lower selection intensity (5% or 10%) had worse results. Culling of cows and discarding of first-calvers for slaughter led to lower genetic and economic contribution. The gain of embryo transfer was also lower; moreover, it is not economically advantageous for its very high costs, so it should not be used in production herds generally. High genetic and economic gain was recorded for replacement of all heifers by animals with higher breeding value from other populations. Keywords: dairy cattle, breeding policy, selection, genetic contribution, economic contribution, gene flow Metod Journal: Czech Journal of Animal Science Pages: 439-449 Volume: 50 Issue: 10 Year: 2005 DOI: 10.17221/4246-CJAS File-URL: http://cjas.agriculturejournals.cz/doi/10.17221/4246-CJAS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/cjs-200510-0001.txt Handle: RePEc:caa:jnlcjs:v:50:y:2005:i:10:id:4246-CJAS Template-Type: ReDIF-Article 1.0 Author-Name: J. Třináctý Author-Workplace-Name: Research Institute for Cattle Breeding, Ltd., Rapotín, Pohořelice Workplace, Czech Republic Author-Name: M. Richter Author-Workplace-Name: Research Institute for Cattle Breeding, Ltd., Rapotín, Pohořelice Workplace, Czech Republic Author-Name: J. Pozdíšek Author-Workplace-Name: Research Institute for Cattle Breeding, Ltd., Rapotín, Pohořelice Workplace, Czech Republic Author-Name: Z.M. Kowalski Author-Workplace-Name: Department of Animal Nutrition, Agricultural University of Cracow, Cracow, Poland Author-Name: E. Fajmonová Author-Workplace-Name: Department of Animal Nutrition, Mendel University of Agriculture and Forestry, Brno, Czech Republic Title: A comparison of parameters of the passage of nylon capsules and digesta calculated from faecal excretion data obtained in lactating cows Abstract: The aim of the study was to compare parameters of passage of nylon capsules and digesta represented by Cr-labelled maize silage through the digestive tract of dairy cows. The capsules were made of nylon cloth (42 µm pore size, 10 mm outside diameter) and applied orally. The evaluation was carried out in dairy cows with milk yield of 19.0 kg/day. The diet (17.6 kg DM/day) consisted of maize silage, lucerne hay and concentrate. Total mean retention time (TMRT), delay time (τ), summarised compartmental mean retention time (CMRTS), and mean individual compartmental retention times (CMRT1 and CMRT2) were calculated. TMRT, τ, CMRTS, CMRT1 and CMRT2 values of nylon capsules and Cr-labelled silage were 36.2 and 45.4 h (P < 0.01), 16.2 and 8.3 h (P < 0.01), 20.1 and 37.2 h (P < 0.01), 7.8 and 8.5 h, 12.2 and 28.7 h (P < 0.05), respectively. The calculated mean retention time of nylon capsules in the reticulo-rumen (CMRTS) was shorter and in the intestines (τ) was longer than that of digesta. For this reason the estimation of digestibility using the nylon capsule method can be questionable. Keywords: nylon capsule, Cr-labelled silage, rate of passage, dairy cow Journal: Czech Journal of Animal Science Pages: 450-458 Volume: 50 Issue: 10 Year: 2005 DOI: 10.17221/4241-CJAS File-URL: http://cjas.agriculturejournals.cz/doi/10.17221/4241-CJAS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/cjs-200510-0002.txt Handle: RePEc:caa:jnlcjs:v:50:y:2005:i:10:id:4241-CJAS Template-Type: ReDIF-Article 1.0 Author-Name: P. Daněk Author-Workplace-Name: Research Institute of Animal Production, Prague-Uhříněves, Kostelec nad Orlicí Workplace, Czech Republic Author-Name: A. Paseka Author-Workplace-Name: Private consultant, Prague, Czech Republic Author-Name: J. Smola Author-Workplace-Name: Faculty of Veterinary Medicine, University of Veterinary and Pharmaceutical Sciences, Brno, Czech Republic Author-Name: J. Ondráček Author-Workplace-Name: Faculty of Veterinary Medicine, University of Veterinary and Pharmaceutical Sciences, Brno, Czech Republic Author-Name: R. Bečková Author-Workplace-Name: Research Institute of Animal Production, Prague-Uhříněves, Kostelec nad Orlicí Workplace, Czech Republic Author-Name: M. Rozkot Author-Workplace-Name: Research Institute of Animal Production, Prague-Uhříněves, Kostelec nad Orlicí Workplace, Czech Republic Title: Influence of lecithin emulsifier on the utilisation of nutrients and growth of piglets after weaning Abstract: The influence of supplementation of a lecithin emulsifier (0.1%) to the feed mixture for piglets after weaning was studied. 16 piglets in the control group (C - without lecithin) and 16 piglets in an experimental (E) group were monitored in three replications in a 28-day experimental period. We observed higher digestibility of monitored nutrients in the experimental group (crude fat: C = 66.28 ± 12.11, E = 69.75 ± 9.85%, crude protein: C = 78.72 ± 5.47, E = 82.17 ± 2.23%, crude fibre: C = 56.70 ± 12.85, E = 59.10 ± 12.04%, nitrogen free extract: C = 86.67 ± 3.32, E = 87.75 ± 3.00%, ash: C = 63.63 ± 11.59, E = 65.73 ± 10.35%). Statistically insignificantly higher daily average gain (C = 374.1 ± 107.0, E = 399.1 ± 104.7 g) of experimental groups and a lower feed conversion ratio (C = 2.285 ± 0.416, E = 1.768 ± 0.048 kg/kg) were found out. It was also confirmed in an additional field experiment (C = 279, E = 312 piglets from birth to 71 days of age) where average daily gain weight was 270 g in control and 290 g in experimental group. The influence of lecithin on the occurrence of haemolytic strains of Escherichia coli was not proved. This experiment confirmed a positive effect of the lecithin emulsifier supplement on the efficiency of piglets. Keywords: piglets, weaning, lecithin emulsifier, weight gain, feed conversion ratio, digestibility, E. coli Journal: Czech Journal of Animal Science Pages: 459-465 Volume: 50 Issue: 10 Year: 2005 DOI: 10.17221/4245-CJAS File-URL: http://cjas.agriculturejournals.cz/doi/10.17221/4245-CJAS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/cjs-200510-0003.txt Handle: RePEc:caa:jnlcjs:v:50:y:2005:i:10:id:4245-CJAS Template-Type: ReDIF-Article 1.0 Author-Name: D. Jalč Author-Workplace-Name: Institute of Animal Physiology, Slovak Academy of Sciences, Košice, Slovak Republic Author-Name: M. Čertík Author-Workplace-Name: Faculty of Chemical Technology, Slovak Technical University, Bratislava, Slovak Republic Title: Effect of microbial oil, monensin and fumarate on rumen fermentation in artificial rumen Abstract: The objective of this study was to investigate the effect of microbial oil on rumen fermentation of a diet composed of 60% hay and 40% barley in an artificial rumen (Rusitec). Microbial oil (MO) was produced by the fungus Thamnidium elegans. This fungus grew on the wheat bran/spent malt grains (3:1) mixture. The fatty acid composition of microbial oil was as follows: 0.7% C14:0, 15.4% C16:0, 10.1% C18:0, 50.9% C18:1, 13.9% C18:2 and 8.4% C18:3 (GLA, γ-linolenic acid). The effect of monensin MON (66 ppm) and fumarate FUM (6.25 mmol) with and without MO supplementation was also studied. The experiment in Rusitec lasted 11 days. After a stabilization period (5 days), MO was added to fermentation vessel V2 (6 days), MON to fermentation vessel V3 (6 days) and FUM to fermentation vessel V4 (6 days). MO was also added to V3 and V4 on the last day together with MON (V3) and FUM (V4). The fermentation vessel V1 served as control (without additives). The results showed that MO reduced (P < 0.05) mol% acetate and increased (P < 0.05) mol% propionate and n-butyrate. Methane production (mmol/day) was reduced numerically (NS). The efficiency of microbial synthesis (EMS) was also reduced numerically and nitrogen incorporated by the microflora (NM) was reduced significantly in MO supplementation. There were no differences in the rumen fermentation when MO was applied together with MON and FUM compared to the vessel where only MO was applied. No additive effect was observed in the relationship MO-ionophore or MO-FUM. Monensin and fumarate applied separately showed their typical effects on rumen fermentation in vitro. Keywords: microbial oil, monensin, fumarate, rumen fermentation, artificial rumen Journal: Czech Journal of Animal Science Pages: 467-472 Volume: 50 Issue: 10 Year: 2005 DOI: 10.17221/4238-CJAS File-URL: http://cjas.agriculturejournals.cz/doi/10.17221/4238-CJAS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/cjs-200510-0004.txt Handle: RePEc:caa:jnlcjs:v:50:y:2005:i:10:id:4238-CJAS Template-Type: ReDIF-Article 1.0 Author-Name: E. Hohausová Author-Workplace-Name: Hydrobiological Institute of the ASCR, České Budějovice, Czech Republic Author-Name: P. Jurajda Author-Workplace-Name: Institute of Vertebrate Biology of the ASCR, Brno, Czech Republic Title: Restoration of a river backwater and its influence on fish assemblage Abstract: The development of fish assemblage in a restored river backwater (Kurfürst backwater, Morava River, Czech Republic) was monitored over a six-year period from its restoration. The structure of fish assemblage remained similar throughout the years. Species richness of adult fish increased from twelve species during the restoration to 20 after it. Initially steady fish abundance (mean 52.3-98.1 inds/ha) and biomass (mean 5.8-7.6 kg/ha) increased significantly in 1999 five years after restoration (576.9 inds/ha and 23.3 kg/ha, respectively). The main resident species were pike Esox lucius, roach Rutilus rutilus, rudd Scardinius erythrophthalmus and perch Perca fluviatilis. High abundance of bleak Alburnus alburnus and chub Leuciscus cephalus was related to their spring spawning period. The structure of the 0+ fish assemblage was similar throughout the years, with chub and bleak prevailing during the restoration, and roach, chub and rudd after it. The number of 0+ species increased from seven to 17. The monitoring documented that the restoration could be considered as beneficial for the fish assemblage. Habitat development of the backwater is likely to influence its current value as a refuge, spawning site and nursery for local fish populations. Keywords: rehabilitation, monitoring, colonisation, floodplain, Morava River, assemblage development, adult fish, 0+ fish, freshwater Journal: Czech Journal of Animal Science Pages: 473-482 Volume: 50 Issue: 10 Year: 2005 DOI: 10.17221/4244-CJAS File-URL: http://cjas.agriculturejournals.cz/doi/10.17221/4244-CJAS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/cjs-200510-0005.txt Handle: RePEc:caa:jnlcjs:v:50:y:2005:i:10:id:4244-CJAS Template-Type: ReDIF-Article 1.0 Author-Name: E. Krupa Author-Workplace-Name: Research Institute of Animal Production, Nitra, Slovak Republic Author-Name: M. Wolfová Author-Workplace-Name: Research Institute of Animal Production, Prague-Uhříněves, Czech Republic Author-Name: D. Peškovičová Author-Workplace-Name: Research Institute of Animal Production, Nitra, Slovak Republic Author-Name: J. Huba Author-Workplace-Name: Research Institute of Animal Production, Nitra, Slovak Republic Author-Name: Z. Krupová Author-Workplace-Name: Research Institute of Animal Production, Nitra, Slovak Republic Title: Economic values of traits for Slovakian Pied cattle under different marketing strategies Abstract: Economic values of 15 production and functional traits for Slovakian Pied cattle were calculated under different marketing strategies. The traits were as follows: birth weight of calves, daily gain of calves in fattening, mature weight of cows, weight of calves at 120, 210 (weaning weight) and 365 days (yearling weight) of age, dressing percentage, mean class for fleshiness and fat covering, conception rate of heifers and cows, losses of calves at calving and from 48 hours to weaning, lifetime of cows and mean class for calving performance. A purebred cow-calf pasture system producing its own female and male replacement was assumed for all strategies. The following marketing strategies for surplus weaned female and male calves were taken into account: (A) export of all surplus calves, (B) intensive fattening of all surplus calves, (C) rearing and selling of all surplus non-pregnant (1) or pregnant (2) breeding heifers and fattening or export of surplus male calves. All calculations were carried out with the computer program Ecoweight. The relative economic importance of traits was calculated multiplying the economic values by the genetic standard deviations of the traits. The lifetime of cows was the most important trait when applying export or fattening of all calves or when selling pregnant breeding heifers, whereas the yearling weight was even more important for the strategy with selling non-pregnant heifers. The second most important trait was weaning weight in strategy A, yearling weight in strategy B and lifetime of cows in marketing strategy C. Carcass conformation traits had the lowest economic importance in all calculations. Keywords: cattle, Slovakian Pied cattle, bio-economic model, economic weights, beef traits, functional traits, marketing strategies Journal: Czech Journal of Animal Science Pages: 483-492 Volume: 50 Issue: 10 Year: 2005 DOI: 10.17221/4235-CJAS File-URL: http://cjas.agriculturejournals.cz/doi/10.17221/4235-CJAS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/cjs-200510-0006.txt Handle: RePEc:caa:jnlcjs:v:50:y:2005:i:10:id:4235-CJAS