Template-Type: ReDIF-Article 1.0 Author-Name: G. Mészáros Author-Workplace-Name: Slovak University of Agriculture, Nitra, Slovak Republic Author-Name: J. Wolf Author-Workplace-Name: Institute of Animal Science, Prague-Uhříněves, Czech Republic Author-Name: O. Kadlečík Author-Workplace-Name: Slovak University of Agriculture, Nitra, Slovak Republic Title: Factors affecting the functional length of productive life in Slovak Pinzgau cows Abstract: A proportional hazard model was used to analyze the impact of the most important factors on the length of productive life in 44 796 Slovak Pinzgau cows. The calculations were carried out with Survival Kit 3.12. The milk production level within a herd was the most important factor. The relation between the milk production level and the culling risk was strongly non-linear. Cows with extremely low milk production (less than 1.5 standard deviations below average) had a 4.8 times higher culling risk than average cows. The culling risk for the highest yielding cows was about one half of the risk of average cows. In the first lactation the culling risk was highest at the beginning and decreased in the course of lactation whereas in subsequent lactations the culling risk was highest at the end of lactation. The risk decreased with parity. The effect of age at first calving did not have a large influence on the length of productive life, although a linear increase in culling risk was observed as the age at first calving increased. Cows from expanding herds were at lower risk to be culled compared to cows in herds of stable and decreasing size. Keywords: cattle, functional traits, longevity, survival analysis, risk ratio Journal: Czech Journal of Animal Science Pages: 91-97 Volume: 53 Issue: 3 Year: 2008 DOI: 10.17221/2712-CJAS File-URL: http://cjas.agriculturejournals.cz/doi/10.17221/2712-CJAS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/cjs-200803-0001.txt Handle: RePEc:caa:jnlcjs:v:53:y:2008:i:3:id:2712-CJAS Template-Type: ReDIF-Article 1.0 Author-Name: G. Kusec Author-Workplace-Name: Faculty of Agriculture, Josip Juraj Strossmayer University of Osijek, Osijek, Croatia Author-Name: G. Kralik Author-Workplace-Name: Faculty of Agriculture, Josip Juraj Strossmayer University of Osijek, Osijek, Croatia Author-Name: I. Djurkin Author-Workplace-Name: Faculty of Agriculture, Josip Juraj Strossmayer University of Osijek, Osijek, Croatia Author-Name: U. Baulain Author-Workplace-Name: Institute for Animal Breeding Mariensee, Federal Agricultural Research Center (FAL), Neustadt, Germany Author-Name: E. Kallweit Author-Workplace-Name: Institute for Animal Breeding Mariensee, Federal Agricultural Research Center (FAL), Neustadt, Germany Title: Optimal slaughter weight of pigs assessed by means of the asymmetric S-curve Abstract: The present study was carried out on 68 barrows equally distributed into two different feeding groups (intensive and restricted). MR tomography was used to obtain data needed for the calculation of optimal slaughter weight. Growth analyses and predictions were performed using an asymmetric S-function. The differences between the predicted and real time needed to achieve 100 kg live weight calculated for the two feeding groups of pigs were not statistically significant. The prediction was fairly accurate in 88% of the cases for the intensive group and 79% of the cases for the restrictively fed pigs. The point of muscle growth saturation (tC = 51.31 dm3) calculated for pigs from the intensive group occurred at 164 days of age. Restrictively fed pigs reached this point after 167 days. It was calculated that at 164 days of age intensively fed pigs reached about 126 kg; the pigs from the restricted group reached about 112 kg at 167 days. These weights can be regarded as optimal slaughter weights for pigs from the present study in the sense of maximum utilisation of muscle growth. Since both groups of pigs reach the same muscle volume of 51 dm3 at the estimated times, the difference in live weights can be attributed to the volume of fat. This makes the intensive system of feeding undesirable in economical pig production. It is concluded that the obtained parameters of the asymmetric S-function can be used for the growth analysis of other pigs, assuming that they are of the same genetic background and reared in the same conditions. It is suggested that the carcass values of pigs slaughtered at optimum live weights proposed here should be compared with the values of pigs slaughtered at other live weights in order to decide between maximum utilisation of muscle growth or achieving the most desirable lean percentage in carcass. Keywords: pigs, feeding regime, growth, prediction, non-linear models Journal: Czech Journal of Animal Science Pages: 98-105 Volume: 53 Issue: 3 Year: 2008 DOI: 10.17221/328-CJAS File-URL: http://cjas.agriculturejournals.cz/doi/10.17221/328-CJAS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/cjs-200803-0002.txt Handle: RePEc:caa:jnlcjs:v:53:y:2008:i:3:id:328-CJAS Template-Type: ReDIF-Article 1.0 Author-Name: G. Piccione Author-Workplace-Name: Depatment of Experimental Science and applied Biotechnology, messina University, Messina, Italy Author-Name: S. Casella Author-Workplace-Name: Depatment of Experimental Science and applied Biotechnology, messina University, Messina, Italy Author-Name: F. Fazio Author-Workplace-Name: Depatment of Experimental Science and applied Biotechnology, messina University, Messina, Italy Author-Name: P. Pennisi Author-Workplace-Name: Department of Agronomic, Agrochemical Science and Animal Productions, Catania University, Catania, Italy Title: Effect of shearing on some haematochemical parameters in ewes Abstract: The aim of the present paper was to study the effect of shearing on some haematochemical parameters in ewes. Forty Valle del Belice ewes, clinically healthy and well-fed, were divided into two groups of twenty subjects each. Twenty ewes were let unshorn as a control group (Group A) and twenty ewes were shorn (Group B). After the blood collection by means of jugular venipuncture, some haematochemical parameters were assessed for each subject in the following experimental conditions: before shearing, 1st, 15th, 30th, 45th, 60 and 75th day after shearing. We studied the course of the following haematochemical parameters: glucose, β-hydroxybutyrate, NEFA, triglycerides, total cholesterol, total protein, urea and creatinine. Two-way repeated measures analysis of variance (ANOVA), followed by Bonferroni's test, was used to determine significant differences between the two groups in the studied parameters. The statistical analysis showed statistical differences (P < 0.05 was considered statistically significant) in β-hydroxybutyrate, NEFA, total protein and urea. Data analysis of variance showed a significant effect of time, with P < 0.0001, on all studied parameters. These results suggest that shearing induces adaptive metabolic responses in the ewes and exposure to elevated ambient temperature induces modifications of some haematochemical parameters. Keywords: Valle del Belice, heat stress, thermal homeostasis, thermoregulation Journal: Czech Journal of Animal Science Pages: 106-111 Volume: 53 Issue: 3 Year: 2008 DOI: 10.17221/2713-CJAS File-URL: http://cjas.agriculturejournals.cz/doi/10.17221/2713-CJAS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/cjs-200803-0003.txt Handle: RePEc:caa:jnlcjs:v:53:y:2008:i:3:id:2713-CJAS Template-Type: ReDIF-Article 1.0 Author-Name: B. Skapetas Author-Workplace-Name: Department of Animal Production, Technological Educational Institute of Thessaloniki, Thessaloniki, Greece Author-Name: J. Katanos Author-Workplace-Name: Department of Animal Production, Technological Educational Institute of Thessaloniki, Thessaloniki, Greece Author-Name: V. Laga Author-Workplace-Name: Department of Animal Production, Technological Educational Institute of Thessaloniki, Thessaloniki, Greece Author-Name: Ε. Sinapis Author-Workplace-Name: Department of Animal Production, Faculty of Agriculture, Aristotle University, Thessaloniki, Greece Author-Name: I. Hatziminaoglou Author-Workplace-Name: Department of Animal Production, Faculty of Agriculture, Aristotle University, Thessaloniki, Greece Title: Vacuum level for opening the teat sphincter and the change in the teat end wall thickness in response to the machine milking of indigenous Greek goats Abstract: The aim of this paper was to study some of the teat characteristics involved in the milking ability of indigenous Greek goats such as the vacuum level of the milking machine that is required for the opening of the teat canal sphincter and the changes in the teat end wall thickness induced by milking. Thirty-six dams (12 of the first, 12 of the second and 12 of the third and subsequent lactations) were used after weaning (60 ± 5 days). Dams were milked twice a day (8:00 and 18:00 h) for 12 weeks in a milking parlour 1 × 12 side by side of Casse type with 6 milking units and a low milk line and air pipeline. The main functional characteristics of milking machine were: vacuum level 44 kPa, pulsation rate 90 pulsations/min and pulsation ratio 50:50. Every 14 days, during morning and evening milking the vacuum level that was required for the opening of the teat sphincter (VOTS) was measured. The measurement of teat end wall thickness (TEWT) was performed before and after milking. The results of this study showed that during the experimental period the mean VOTS was 23.57 ± 0.36 kPa and decreased significantly as the stage of lactation progressed (P< 0.001). The post-milking TEWT was 3.55% higher in comparison with that before milking (P < 0.01). A continuous and significant decrease in teat thickness was observed during the lactation stage (P < 0.001), which suggests a reaction to intramammary pressure and milk quantity in the udder. The TEWT was affected significantly by the parity (P < 0.01). A positive correlation was found between VOTS and TEWT before and after milking (0.4 and 0.36, respectively). It could be said that a lower vacuum level is required for the opening of the teat sphincter of the udder in goats of the indigenous Greek breed. The thicker teat end wall and more resistant sphincter could be less favourable in the machine milking of goats. Keywords: goat, machine milking, vacuum level, teat thickness, teat sphincter Journal: Czech Journal of Animal Science Pages: 112-118 Volume: 53 Issue: 3 Year: 2008 DOI: 10.17221/2714-CJAS File-URL: http://cjas.agriculturejournals.cz/doi/10.17221/2714-CJAS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/cjs-200803-0004.txt Handle: RePEc:caa:jnlcjs:v:53:y:2008:i:3:id:2714-CJAS Template-Type: ReDIF-Article 1.0 Author-Name: J. Baumgartner Author-Workplace-Name: Slovak Agricultural Research Centre Nitra, Slovak Republic Author-Name: Z. Končeková Author-Workplace-Name: Slovak Agricultural Research Centre Nitra, Slovak Republic Author-Name: J. Benková Author-Workplace-Name: Slovak Agricultural Research Centre Nitra, Slovak Republic Author-Name: D. Peškovičová Author-Workplace-Name: Slovak Agricultural Research Centre Nitra, Slovak Republic Author-Name: J. Simenovová Author-Workplace-Name: Department of Food Technology, Mendel University of Agriculture and Forestry Brno, Czech Republic Author-Name: J. Csuka Author-Workplace-Name: Slovak Agricultural Research Centre Nitra, Slovak Republic Title: Changes in egg quality traits associated with long-term selection for lower yolk cholesterol content in Japanese quail Abstract: In the present paper we describe the basic results of long-term selection for low yolk cholesterol content in Japanese quail and its influence on development and relationship with other egg quality traits during nineteen selected generations. The changes in a selected low cholesterol line were compared with changes in an unselected control line to obtain the real selection response to estimated traits. There was a significant decrease in yolk cholesterol content from 1 815 mg/100 g of fresh yolk (P generation) to 1 522 mg/100 g yolk (S19 generation). According to the value of regression coefficient b the decrease per one generation was 15.71 mg/100 g yolk. The decrease in cholesterol of the edible part of egg was also effective and it significantly decreased by 11.29 mg/100 g of the edible part of egg in each generation. There were only insignificant changes in egg weight, but we found a significant increase in yolk weight during selected generations. According to the regression analysis the increase in yolk weight was 0.019 mg/100 g per one generation. There were a positive but insignificant increase also in albumen weight, shell weight and weight of the edible part of egg. We found a small and insignificant decrease in shape index. We determined very high and significant positive correlations between cholesterol content in yolk and cholesterol content in the edible part of egg (0.801+++) and significant negative correlations between yolk cholesterol content and egg weight (-0.515+), yolk weight (-0.468+) and weight of the edible part of egg (-0.475). There were only low, positive and insignificant correlations between yolk cholesterol content and yolk egg proportion and egg shape index. Keywords: selection, yolk cholesterol, egg quality traits, correlations, Japanese quail Journal: Czech Journal of Animal Science Pages: 119-127 Volume: 53 Issue: 3 Year: 2008 DOI: 10.17221/2715-CJAS File-URL: http://cjas.agriculturejournals.cz/doi/10.17221/2715-CJAS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/cjs-200803-0005.txt Handle: RePEc:caa:jnlcjs:v:53:y:2008:i:3:id:2715-CJAS Template-Type: ReDIF-Article 1.0 Author-Name: F. Jančík Author-Workplace-Name: Institute of Animal Science, Prague-Uhříněves, Czech Republic Author-Workplace-Name: Faculty of Agriculture, University of South Bohemia in České Budějovice, Czech Republic Author-Name: P. Homolka Author-Workplace-Name: Institute of Animal Science, Prague-Uhříněves, Czech Republic Author-Name: B. Čermák Author-Workplace-Name: Faculty of Agriculture, University of South Bohemia in České Budějovice, Czech Republic Author-Name: F. Lád Author-Workplace-Name: Faculty of Agriculture, University of South Bohemia in České Budějovice, Czech Republic Title: Determination of indigestible neutral detergent fibre contents of grasses and its prediction from chemical composition Abstract: Five grass species (Dactylis glomerata L., Phleum pratense L., Lolium perenne L., Festuca arundinacea L.) and the hybrid Felina (Lolium multiflorum L. × Festuca arundinacea L.), commonly used in roughages for ruminants, were harvested at different maturities of primary growth (n = 60) and evaluated for contents of dry matter (DM), crude protein (CP), ash, crude fat, neutral detergent fibre (NDF), acid detergent fibre (ADF), acid detergent lignin (ADL), indigestible neutral detergent fibre (INDF) and digestible neutral detergent fibre (DNDF). INDF and DNDF contents were determined by in sacco rumen degradation of grasses for 12 days in non-lactating cows. ADL content was found to be highly correlated (P < 0.05) with DNDF (r = -0.87) and presented a reliable (R2 = 0.78; residual mean square error of 17.65 g/kg DM; P < 0.0001) parameter to predict INDF contents. Over a six-week period of maturation INDF contents increased (P < 0.0001) in all studied grasses. It was confirmed by this study that the INDF contents of grasses, which markedly increased during maturation, could be effectively predicted from ADL contents. Keywords: grass, indigestible neutral detergent fibre, in sacco method Journal: Czech Journal of Animal Science Pages: 128-135 Volume: 53 Issue: 3 Year: 2008 DOI: 10.17221/2716-CJAS File-URL: http://cjas.agriculturejournals.cz/doi/10.17221/2716-CJAS.html File-Format: text/html X-File-Ref: http://agriculturejournals.cz/RePEc/caa/references/cjs-200803-0006.txt Handle: RePEc:caa:jnlcjs:v:53:y:2008:i:3:id:2716-CJAS