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Measurements were done of some lysosomal proteolytic enzyme activities involved in skeletal muscle proteolysis of the masculus longissimus lumborum et thoracis muscle (MLLT) of bulls. Samples from the same region between the 11th and 13th vertebra were taken after slaughter from Limousin (n = 10), Hereford (n = 10), Charolais (n = 10), Angus (n = 11) and Simmental (n = 11) bulls about 15 months old fed complete diet 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 proteinases inhibitor) acid (LIA) autolytic activities were measured in the presence of 1mM Mg⁺⁺. MLLT was also analysed for RNA, DNA and protein variables. The data were processed by analysis of variance. The highest activities in PSCatD (P ≤ 0.05), AAA (P ≤ 0.01) and LIA (P ≤ 0.05) as well as percentage of inhibition by pepstatin in cathepsin D (P ≤ 0.01) were estimated in Angus bulls, and the lowest in Limousin ones. These breeds differed in the above-mentioned activities by 20.3, 21.1, 31.1 and 13.1%, respectively. RNA/g of tissue was highest in Hereford and lowest in Limousin bulls (by about 15.3%, P ≤ 0.01). Similar differences (14.3%) were between Charolais and Limousin (P ≤ 0.01). CPS (10³ RNA/protein) was higher by 18.3% (P ≤ 0.01) in Charolais compared to the value in Simmental bulls; similar differences were between Hereford and Simmental (16.4%, P ≤ 0.01). The DNA concentration was highest in Hereford (by about 30%) compared to Charolais bulls. Protein/10³DNA ratio (mg/mg) - FCS - was higher by 33.4% in Charolais compared toHereford; RNA/DNA ratio was higher by 40.2% in Charolais compared toLimousin bulls. These results indicate the fast turnover of proteins in the groups of examined bulls and it can be concluded that in hypertrophic MLLT of bulls an anabolic decrease in degradation occurred.

The objective of this study was to determine how non-nutritional factors such as herd, parity, days in milk, milk production, and milk components affect the concentration of milk urea. A retrospective, observational study comprising analyses of individual cow records from monthly dairy herd improvement milk tests including milk urea tests was conducted. Six commercial Holstein dairy herds were involved in the investigation from October 2000 to September 2003. The data were evaluated using the mixed linear model with repeated measures, and parameters were estimated by the REML method. Significant differences in milk urea concentrations were observed between herds (P < 0.0001), with a significant variability between test dates within herds. Significant effects of parity (P = 0.0003), days in milk (P < 0.0001), and their interaction were also found. Higher concentrations of milk urea were determined in the cows on the first and second parity (5.63 and 5.62 mmol/l, respectively) compared to the groups of cows on the third and fourth parity (5.47 mmol/l). It was found that milk urea concentration increased with the square of milk yield (P < 0.0001), while a negative quadratic relationship was found between milk urea concentration and milk fat % (P < 0.0001). It was concluded that milk urea concentration should be evaluated in association with days in milk, milk yield, milk fat %, and milk protein %.

The first part of the study concerns the effect of the stage of maturity on nutrient content and leaf percentage of lucerne (Medicago sativa). The plants of lucerne were harvested and analysed at several stages of growth. The crop yield and changes in the concentration of nutrients were determined. The leaf percentage from whole herbage and leaf yield were determined as well. The leaf percentage at the growth stage of small buds was significantly (P < 0.05) higher than at the growth stage of bloom in all three cuts (1^st cut 52.7% vs. 46.62%; 2^nd cut 52.03% vs. 44.70%; 3^rd cut 50.58% vs. 46.26%). Crude protein content of lucerne was decreased significantly (P < 0.05) from the large bud growth stage (small buds 219.6 g/kg DM and large buds 203.1 g/kg DM vs. bloom 173.5 and after bloom 154.2). In the second part of the study, the effect of silage additives on fermentation characteristics of lucerne was investigated. The bacterial inoculant (containing homo- and heterofermentative lactic acid bacteria), chemical additive (containing formic acid, propionic acid, ammonium formate and benzoic acid) and the bacterial inoculant with benzoic acid were used for the improvement of fermentation process.The addition of the inoculant with L. buchneri increased acetic acid (P < 0.05) concentration compared to the silage with chemical additive (group I with inoculant - 1.22%; group Ch with chemical additive - 0.84%; group ICh with chemical additive and inoculant - 1.43). Control silage (C) without additive contained 1.14% acetic acid in dry matter.

Skeletal muscle growth is determined by the number of prenatally formed fibres and by the degree of their postnatal hypertrophy; i.e. prenatal development may influence the postnatal growth. Suppression subtractive hybridization (SSH) was used to identify genes more expressed in fetal hind limb muscles of Piétrain pigs (44 days of gestation) compared to the adult biceps femoris. Six potential functional candidate genes (CNN3, DCN, FBN2, POSTN, SPARC and YWHAQ) were selected to verify the SSH results using real-time RT-PCR. Expression levels of the studied genes were significantly higher (P< 0.05) in the fetal muscle compared to the adult muscle. FBN2 and POSTN exhibited the highest mRNA levels (mean relative ratios were 182.7 and 121.6, respectively). The studied genes may play an important role in muscle biology and may be candidates for muscling traits.

Forty female chickens were allocated to four groups of ten birds each. The control group (K) was fed a basal diet without supplementation. The second control group received a basal diet with humic acid (HA) at a dose of 0.5 g per chicken/day. The first experimental group was fed the basal diet with methyl-mercury (MeHg) at a dose of 0.02 mg per chicken/day and the group of chickens MeHg + HA received 0.5 g HA per chicken/day. After slaughter, mercury levels were assessed in liver, kidney, brain and muscle tissue samples. After 10-day treatment of the chickens with MeHg, significantly increased (P < 0.001) Hg concentrations were detected in all examined tissues in comparison with the groups K and HA. The average concentrations in liver, kidneys, brain and muscle tissues were 424, 398, 81.6 and 79.2 µg Hg/kg, respectively. After concurrent treatment with HA and MeHg, Hg concentrations were lower by 20.6%, 23.8%, 23.0% and 18.6% in liver, kidneys, brain and muscle tissues (P < 0.001). Biological accumulation of Hg was 25.5% and 20.4% in MeHg and MeHg + HA groups, respectively.

The objective of the study was to verify the hypothesis that GEN (genistein - phytoestrogen and an inhibitor of tyrosine protein kinase - TPK) effects on pig oocyte maturation and cumular cell expansion under in vitro conditions are connected with its estrogenic activity. Oocytes were cultivated for 24 hours up to the stage of the first meiotic metaphase (MI). Three different doses of GEN (13, 40, 80 µg/ml of medium) and also three doses of GIN, genistin, an analogue of GEN without effects on TPK, (80, 160 and 240 µg/ml of medium) were tested. To verify the reversibility of GEN effects, the oocytes were first cultivated for 24 hours with 80 µg of GEN per 1 ml of medium and then for another 24 hours without any GEN. GEN blocked pig oocyte maturation at the stage of the germinal vesicle (GV), depending on the dose. After rinsing out the GEN the oocyte maturation recovered, but with abnormalities (32%). GIN in a concentration of 80 µg/ml of medium induced a significant blockage at the GV stage (18%). With an increase in the GIN concentration, the number of oocytes blocked at the GV stage significantly decreased, but the abnormal maturation increased (up to 31%). GEN inhibited the cumular cell expansion in proportion to its dose. GIN had a less pronounced effect. As GEN and GIN effects demonstrate similar patterns, it is probable that estrogenic activity is involved.

This study was conducted to investigate the effects of cage stocking density on egg yield, some egg quality traits and plumage condition in laying hens. Eighteen weeks-old 264 ISA-Brown pullets were divided into four cage density groups. The densities were 2 000, 1 000, 667 and 500 cm² per hen (by allocating 1, 2, 3 and 4 hens per cage; floor area 40 × 50 cm) with 48, 30, 24 and 21 replicate cages, totally 123 three-tier battery cages. During the experimental period from 18 to 53 weeks of age, all birds were provided illumination for 16 hours a day. The hens were fed a diet containing 11.7 MJ ME/kg and 180 g CP during the period of 18 to 40 weeks of age and 11.3 MJ ME/kg and 170 g CP during the period of 41 to 54 weeks of age. Feed and water were available for ad libitum. Egg yield, mortality, live weights at 50% egg production age and at the end of experiment, pecking related mortalities, some egg quality traits and plumage condition were recorded weekly. Hen-housed egg production, egg mass, viability, and live weights were significantly decreased by higher densities. Most of the egg quality traits were not affected by cage densities. Pecking related mortalities increased in cage densities of 667 cm² and 500 cm² per hen compared to the other densities (P < 0.05) while plumage scores were higher in all body parts of hens kept in cages of 2 000 cm² and 1 000 cm² densities compared to the higher densities. The results showed that brown laying hens should be kept in cages having 1 000-2 000 cm² densities in order to improve their welfare and performance.

The frequent presence of rye translocation 1B/1R in common wheat is well known as well as its unfavourable effect on bread-making quality. These translocated materials make up more than one tenth of all wheat varieties registered in the Czech Republic and due to their lower technological value they are predominately used for livestock feeding in spite of the lack of information about their desirability for monogastric animals. Our study was aimed at a general effect of 1B/1R translocation, including other grain characteristics in model feeding tests with laboratory rats. Triennial evaluation of selected chemical and technological characteristics of winter wheat grain, including feeding characteristics in the model set of 18 DH lines with/without 1B/1R translocation, confirmed a highly significant effect of year on evaluated parameters. Wheat lines with the presence of 1B/1R translocation showed a significantly higher value of relative viscosity, crude protein content and higher proportion of the albumin + globulin fraction. This was manifested negatively in the technological characteristics of the gluten index (GI) and the Zeleny sedimentation test of these wheat lines. Detected values of relative viscosity, grain hardness (PSI) and albumin-globulin fraction were significantly influenced by the genotype of the wheat line. The relationships of evaluated grain characteristics to the results of feeding test were not unequivocal. The presence of 1B/1R translocation significantly decreased the values of balance in these characters: net protein utilization (NPU) and biological value of proteins (BV), however the effect of the 1B/1R translocation on protein efficiency ratio (PER) was not confirmed. Correlation analyses showed low mutual relationships among the parameters of balance and growth tests. A lower but significant positive correlation of the albumin + globulin fraction and a negative correlation of storage proteins with growth parameter PER were also observed. It is possible to summarize that individual relation between albumins + globulins and gluten protein composition of grains influenced the values of PER more significantly than the presence of 1B/1R translocation.

: Nutrient digestibility and parameters of nutritive value for ruminants of two winter wheat (Triticum aestivum L.) cultivars were evaluated by means of an in vivo balance trial performed by the regression method on two groups of heifers with an increasing proportion of grain in DM (from 6 to 46%). Sulamit and Rapsodia, chosen on the basis of the in vitro test from a set of 25 cultivars (grown in 2002-2004) reached significant differences in DM fermentability in vitro (by 43.7-78.6 ml/g DM, P < 0.05). In vivo digestibility of crude protein, nitrogen-free extract, organic matter, parameters of N retention, energy concentrations (metabolisable energy, net energy for lactation and for fattening) and parameters in the PDI system (especially PDIE) increased along with the grain proportion in the diet. At the comparable proportion of grain in the ration the positive differences were significantly higher (P < 0.05) for Sulamit than Rapsodia.

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.

Lucerne (Medicago sativa L. var. Palava), harvested at four successive dates over a 30-day period, was evaluated for chemical composition (dry matter, organic matter, crude protein, ether extract, crude fibre, nitrogen-free extract, neutral detergent fibre, acid detergent fibre, acid detergent lignin), amino acid contents and intestinal digestibility in dairy cows. Dry matter (r = 0.78), organic matter (r = 0.95), crude fibre (r = 0.91), neutral detergent fibre (r = 0.94), acid detergent fibre (r = 0.79) and acid detergent lignin (r = 0.48) presented positive linear correlation coefficients (r) with growth stage, whereas crude protein (r = -0.96), ether extract (r = -0.86) and nitrogen-free extract (r = -0.70) showed negative relationships. Total essential amino acid content decreased (r = -0.94) from 84.1 to 55.3 g/kg of dry matter with maturity, with r-values higher than -0.90 obtained between growth stage and contents of lysine, methionine, threonine and valine. With the exception of tyrosine (r = -0.68), r-values between growth stage and individual non-essential amino acids were all higher than -0.90. Total amino acid (r = -0.98) and nitrogen (r = -0.99) contents presented comparable tendencies with successive sampling times. Whereas no definite trends were detected for the amino acid composition of rumen incubated (16 hours) lucerne samples, the intestinal digestibility of total essential (r = -0.78), total non-essential (r = -0.58) and total (r = -0.69) amino acids as well as nitrogen (r = -0.99) decreased with growth. However, due to a small sample size (n = 4), most linear relationships between constituents and growth stage were insignificant. It can be concluded that, although limited in the sample size, this report presents information on the decrease in amino acid contents and intestinal amino acid digestibility as growth proceeds in lucerne (var. Palava) produced in the Czech Republic, which could be utilized in the feeding of ruminants.

Before being used for insemination, young bulls of Czech Fleckvieh (CF) are tested for growth at performance-test stations. While at stations, the bulls are weighed monthly. Evaluation included 7 448 bulls with 82 676 records of weight measured from 6 to 520 days of life. In the station-year-period (HYS), which can be prolonged up to 3 months, different groups were tested according to the beginning of growth curve and according to test-days of weighing. Weight analyses were used to handle heterogeneous variability based on age. Legendre Polynomials (LP) with 5 parameters described the average growth curve for HYS classes. Deviations from average curves were decomposed into genetic (G), animal's permanent environment (PE) and residual (RES) components. Functions of (G) and (PE) were tested using LP random regression (RR) methodology with 5 or 3 parameters and Linear Spline (SP) function with 5 knots. Variance increases with the age of the animals. From 100 to 400 days, heritability was nearly the same with a mild depression in the middle of the period. The average was h² = 0.31 and ended with h² = 0.36. Results were similar for variance components, heritability, genetic, environmental and phenotype correlations from different models with different LP and SP functions. Higher RES variability occurred only for LP with 3 parameters. For traits like live weight, the RR should have at least 3 parameters and SP function should be used.

The aim of the study was to evaluate the growth rate and selected carcass and meat quality parameters in bulls fed a high-grain diet and to compare the results with those obtained in bulls fed a diet based on preserved roughage. The trial included 18 Czech-Pied bulls fed a diet with a high proportion of concentrated feed and 18 Czech-Pied bulls fed a diet based on maize silage, used as a control group. The trial was launched after the weaning of calves. During the fattening period, live weight and average daily weight gain were monitored. The bulls were slaughtered at the live weight of 550-600 kg, the mean age at slaughter was 473 days for the high-grain diet group and 474 days for the control group. The carcasses were classified to SEUROP quality grades, and carcass gain and dressing percentage were calculated. Samples of m. longissimus pars thoracis were taken from five bulls in each group to examine selected meat quality parameters. In the period from weaning to slaughter the high-grain diet bulls and the control bulls achieved the average daily weight gain of 1.29 kg and 1.21 kg, respectively. Differences between the groups were not significant. The high-grain diet group showed higher average carcass weight and higher carcass weight gain, differences between the groups were not significant, either. As to meat quality parameters under study, a significant difference was found only in meat lightness (L*), with the mean value in the high-grain diet group being significantly (P ≤ 0.01) lower than in the control group. The other meat quality parameters did not show any significant differences between the groups. In this study, the high-grain diet gave similar performance as the maize silage-based diet in fattening bulls. The high-grain diet group and control group showed comparable average daily weight gain and selected carcass and meat quality parameters.

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.

The evaluation of the effect of the stage of lactation on milk composition, its properties and the quality of rennet curdling was carried out over the period of three successive years using milk samples (n = 162) obtained from a total of 27 ewes of the East Friesian (EF) breed, reared on a small sheep farm in Juřinka in the region of Wallachia. The stage of lactation had a highly significant effect on the contents of all milk components. However, only the contents of total solids (TS), solids non-fat (SNF), fat (F), protein (P) and casein (CN) gradually increased with the advancement of lactation. The stage of lactation also had a highly significant effect both on all the properties of milk and the rennet curdling quality (RCQ). All phenotypic correlations between the particular contents of TS, SNF, F, P, CN and urea nitrogen (UN) were positive and high (P ≤ 0.001). On the other hand, all phenotypic correlations between milk yield and particular contents of TS, SNF, F, P, CN and UN were negative and high (P ≤ 0.001). The majority of phenotypic correlations between rennet clotting time (RCT) and the other particular parameters was insignificant. However, the phenotypic correlations between lactose (L) and RCT and between pH and RCT were positive and high (P ≤ 0.001) whereas the phenotypic correlation between titratable acidity (TA) and RCT was negative and high (P ≤ 0.001). The majority of phenotypic correlations between the rennet curdling quality (RCQ) and the other particular parameters was insignificant. Nevertheless, the phenotypic correlations between pH and RCQ and between RCT and RCQ were positive and high (P ≤ 0.001) whereas the phenotypic correlation between TA and RCQ was negative and high (P ≤ 0.001).

The objective of this paper is to evaluate the contents of CF, NDF, ADF and ergosterol in the forage of Fistulolium, Dactylis glomerata and Arrhenatherum elatius from stands harvested at the end of the growing season. The contents of CF, NDF and ADF were analysed using the ANKOM Fibre Analyzer instrument. The ergosterol content was analysed by the HPLC method. The lowest CF content was in the Festulolium forage matter (26.8%). Conversely, the highest content was in the Arrhenatherum elatius forage (30.2%). The CF content gradually increased during autumn from 28.0% to 29.4%. Likewise, the NDF and ADF contents were lowest in Festulolium (58.3% and 32.3%, respectively). The highest NDF content was in Arrhenatherum elatius (60.5%). The ADF contents in Arrhenatherum elatius and Dactylis glomerata were comparable (35.9% and 35.1%, respectively). The NDF content increased during autumn from 56.4% to 62.0% and ADF content from 32.8% to 36.4%. The ergosterol content suggests a lower infestation of the Festulolium forage by fungi. While this content in the Festulolium forage was 94.9 mg/kg of dry matter (DM), in the Dactylis glomerata forage it was 136.7 mg/kg DM and in the Arrhenatherum elatius forage 139.9 mg/kg DM. Forage samples taken in December contained ergosterol on a level of 248.6 mg/kg DM. The species under study and the time of use in autumn exhibited a statistically highly significant effect (P < 0.01) on the contents of CF, NDF, ADF and ergosterol in the forage matter.

The milk urea concentration (MUC) is a respected indicator of the health and nutrition status of dairy cows. It is in relation to their reproduction performance, longevity and technological milk indicators. The accuracy of the interpretation of results depends on their reliability, which is so important. There are a lot of principles of MUC analyses. Their results can be affected by a number of interferential factors. Many disproportions were noticed for the above-mentioned reasons in laboratory practice. That is the reason why relevant result variation sources are studied. The goal of this paper was to search the relationships between different methods of MUC determination with the use of specifically modified samples on a milk basis with the absence of dissolved components such as lactose. The results of two methods (photometric BI with diacetylmonoxime and FT-MIR (mid infrared)) were disqualified for a large shift and variance of values, unsatisfactory recovery and paralysed relation to other methods (BI r = from 0.184 to 0.213; P > 0.05). Therefore the second BI method was retained in the evaluation, and it was probably a local defect in the performance at disqualification. Nevertheless, the procedure showed poorer recovery (75.5 ± 14.3%) and necessity for methodical modifications for support of result reliability such as increase in the number of calibration points as compared to the contemporary procedure. The results of FT-MIR method were strongly systematically displaced due to lactose absence in particular (by 33.824 ± 3.794 mg/100 ml). Nevertheless, the correlations with results of other relevant methods were tight (from 0.991 to 0.999; P < 0.001). The photometrical method with Ehrlich's agent (para-dimethylaminobenzaldehyde, EH) showed acceptable values of all the evaluated indicators of reliability. The specific Ureakvant method (UR; with conductivity difference measurement) showed the most proper results in combination with all the reliability indicators (recovery as much as 93.2 ± 10.2%; correlation from 0.989 to 1.0; P < 0.001; acceptable ratio of systematic and random error components). It is possible to use the tested specific standard samples for the control or calibration of all methods (BI, EH and UR) with the exception of FT-MIR.

Investigations on the ovarian cycle of fish species that inhabit Hungarian rivers are necessitated by both environmental and economic reasons. The objective of our research was to explore new fundamental knowledge concerning the ovarian cycle of the white bream (Blicca bjoerkna, Linnaeus, 1758), barbel (Barbus barbus, Linnaeus, 1758), orfe (Leuciscus idus, Linnaeus, 1758) and nase (Chondrostoma nasus, Linnaeus, 1758). Histological investigation of ovaries and determination of proportions of oocytes in different stages of development is an appropriate method for the description of spawning characteristics of these species. Our results show that the GSI value for all four investigated species starts to increase at the end of summer and reaches its maximum before spawning. In the barbel and white bream, the presence of oocytes in the stage of cortical alveoli and the heterogeneous size of oocytes in the stage of vitellogenesis in the pre-spawning period indicate that barbel and white bream are multiple spawners. In contrast, in the orfe and nase, the absence of oocytes in the stage of cortical alveoli and the homogeneous size of cells in the stage of vitellogenesis indicate that orfe and nase are single spawners.

Survival Kit V3.12 was used to analyse the length of productive life of cattle in theCzechRepublic. The data set consisted of 230 028 registeredHolstein cows. The model included the time-dependent effects parity × stage of lactation interaction, herd × year × season interaction, class of milk production within herd and year, breed within years and the time-independent effect of age at first calving and the random effect of sire. The highest risk of culling was found for cows at the beginning and at the end of the first lactation and at the end of any other lactation. The risk of culling decreased with parity. The risk of culling of cows assigned to the lowest milk production class was five times higher than that of cows assigned to the average milk production class. Risk of culling diminished with a decreasing percentage ofHolstein breed. Cows younger at first calving showed a lower risk of culling. Breeding values for sires expressed as a risk ratio of their daughters were between 0.7 and 1.45. Estimated heritability of functional longevity was 0.025 on the log scale and 0.041 on the original scale.

There are several ways of generalizing classical growth models to describe the complex nature of animal growth. One possibility is to construct a model based on a sum of several classical growth functions. In this paper, such multiphasic growth models for breeding bulls of the Czech Pied cattle based on the sum of two logistic functions are studied. The logistic function was chosen as a base for the models due to the relatively low degree of nonlinearity for the growth data. The paper describes three steps of constructing such a multiphasic growth model: in the first step a model with four unknown parameters is considered, in the second step the number of model parameters which are to be estimated is increased to five and in the third step a general model with six parameters is used. In each step, statistical properties of the considered model are checked. The residual variability of the best fitting model is on average approx. 8 times lower than the residual variability of classical Gompertz model which is often used by breeders to model cattle growth.

This study was focused on a comparison of the growth characteristics and parameters of three meat-type lines of Japanese quail. The body weight data of wild-type, dotted-white and extended-brown quail lines over time were collected and fitted to Richards equation. The relevant parameters were compared based on the Confidence Interval Test. Confidence Interval Test calculates the percentages of model predictions staying in the confidence intervals of the corresponding experimental data. Both sexes of brown quails showed lower weight gains than the other two lines. Behind the inflection point a decline in the absolute growth rate was slowest for brown females. In general, Richards model parameter values showed deviations of one line from the other lines to a varying extent. Shape parameter for males (0.335-0.618) and maturation index for females (0.067-0.077) tend to be the most critical parameters. When the overall models were used to predict the weight of other lines, the models of white and wild males showed great similarity. Overall model predictions for male brown and white quails, for female brown and wild-type quails showed the largest differences. Like in males, white and wild females were the closest lines but the likeliness percentage was lower than that for males. The proposed method of parameter comparison can be a useful tool for researchers working on biological modelling.

Multiple-lactation random regression model was applied to test-day records of milk, fat and protein yields in the first three lactations of the Czech Holstein breed. Data included 9 583 cows, 89 584, 44 207 and 11 266 test-day records in the first, second and third lactation, respectively. Milk, fat and protein in the first three lactations were analysed separately and in a multiple-trait analysis. Linear model included herd-test date, fixed regressions within age-season class and two random effects: animal genetic and permanent environment modelled by regressions. Gibbs sampling method was used to generate samples from marginal posterior distributions of the model parameters. The single- and multiple-trait models provided similar results. Genetic and permanent environmental variances and heritability for particular days in milk were high at the beginning and at the end of lactation. The residual variance decreased throughout the lactation. The resulting heritability ranged from 0.13 to 0.52 and increased with parity.

In this study, canonical correlation analysis was applied to layer data to estimate the relationships of egg production with age at sexual maturity, body weight and egg weight. For this purpose, it was designed to evaluate the relationship between two sets of variables of laying hens: egg numbers at three different periods as the first set of variables (Y) and age at sexual maturity, body weight, egg weight as the second set of variables (X) by using canonical correlation analysis. Estimated canonical correlations between the first and the second pair of canonical variates were significant (P < 0.01). Canonical weights and loadings from canonical correlation analysis indicated that age at sexual maturity had the largest contribution as compared with body weight and egg weight to variation of the number of egg productions at three different periods.

In an experiment with 18 lactating Chios ewes, the replacement of barley grain, wheat grain, sugar beet pulp and lucerne meal with fermented olive wastes (FOW), maize grain and soybean meal was used to formulate diets that allowed the net energy (NE) for lactation (NE_l) density of FOW to be calculated. In the experiment, which lasted 8 weeks, ewes were allocated, after equal distribution for milk yield, body weight (BW) and lactation number, into three treatments of 6 ewes each in a Youden square experimental design with 4 consecutive periods of 14 days. Ewes in all groups were offered a concentrate mixture ad libitum (1.12 kg/ewe/day, dry matter (DM) basis) and lucerne hay (0.90 kg/ewe/day, DM basis). FOW were added to the concentrate mixture at inclusion levels (on an as-fed basis) of 0, 100 and 200 kg/t for treatments FOW0, FOW100 and FOW200, respectively. There were no differences among groups in milk protein (60.0 g/kg), lactose (53.0 g/kg) or ash (9.6 g/kg) contents, but milk fat content increased linearly (P < 0.01) with increasing dietary levels of FOW. Average milk yield (1 137 g/day) and yields of components tended (P < 0.10) to decrease with increased FOW feeding. The best estimate of the NEl density of FOW was 2.55 MJ/kg DM at 2.7×M NE intake, a value only slightly lower than that of 2.62 at 2.7×M based upon a Van Soest et al. (1984) discount from equations of Van Es (1978), who suggested 3.00 MJ/kg DM at 1.1×M of NE intake. FOW is a low protein, high fibre and low NEl feedstuff that will be of limited value in rations of high producing lactating ewes.

The objective of the paper was to analyse the influence of dairy cow management technology, milking method, predipping and summer grazing on the contamination of cow's raw milk by mesophilic (TBC), psychrotrophic (PBC), lipolytic (PLiBC) and proteolytic (PPrBC) bacteria. The values of TBC, PBC, PLiBC and PPrBC in bulk milk samples were determined by the culture method according to IDF standards. Investigations were carried out in nine stables of seven dairy farms from January 2005 to June 2006. Summer grazing has the most marked influence on the values of studied parameters. Farms with summer grazing had a lower microbial contamination of milk compared to farms without grazing and the difference was statistically highly significant in all studied parameters (P < 0.001). A positive effect of predipping on a reduction in the values of milk microbial contamination was proved while the difference between farms with predipping and those without it was on a significance leve lP < 0.05 to 0.001 except PLiBC. A comparison of the influence of dairy cow management technology indicated the lowest values of all microbiological indicators in loose cubicle littered housing, higher values were determined in stanchion littered housing and the highest in loose slatted-floor housing. A statistical difference between the technologies was proved mainly in TBC (P < 0.001). Farms with milking in milking parlours had a lower microbial contamination of milk compared to farms that used the in-stall milking pipeline system but the difference was statistically significant only in TBC (P < 0.05).

The aim of this research was to determine the slaughter yield, proximate composition, and flesh colour of cultivated and wild perch (Perca fluviatilis). The study material was composed of fish obtained from intense fattening on formulated feed (age 1+, mean body weight (BW 116 g)) and wild specimens caught in a lake (age 3+, BW 119 g). The biometric traits of the two groups of fish did not differ with regard to body weight, total length (Lt), body length (Lc), or condition coefficient (P > 0.01). The cultivated perch had both higher maximum body height (H) and relative body profile (Rp) (P ≤ 0.01). The cultivated perch has a significantly lower slaughter yield (P ≤ 0.01). This dependence stems from the heavier viscera, which included more perivisceral fat and larger liver. Cultivated perch had significantly higher values of the viscerosomatic (VSI; 12.0 vs. 6.4), hepatosomatic (HSI; 1.9 vs. 1.7), and perivisceral fat (IPF; 7.0 vs. 1.2) indices. The analysis of the proximate composition of fillets from wild and cultivated perch indicated that the ratios of protein, fat, water were significantly different (P ≤ 0.01). The higher content of dry matter in the cultivated perch was a result of higher fat and protein contents. The fillets of the two groups of perch differed with regard to the saturation of green and yellow pigment; the cultivated perch exhibited lower values of parameter a* and higher values of parameter b* (P ≤ 0.01).

To determine the effect of weaning system on Awassi sheep milk production and lamb growth, 68 Awassi ewes and their lambs (n = 104) were assigned to one of the following treatment groups a) after 3 days from birth (MIX), ewes were separated from their lambs during the evening for 15 h and milked once daily in the morning, and their lambs were allowed to suckle for 9 h during the day or b) ewes were not milked and suckled by their lambs (DY60) during the first 60 days of lactation. Ewes and their lambs were assigned to the groups according to ewe's age, parturition date, sex of the lamb and birth type. All lambs were weaned at 60 days of age and the ewes were milked twice daily. Milk yield was recorded fortnightly and milk fat composition was recorded monthly. The birth weight of lambs was recorded in the first 2 hours and they were weighed fortnightly until 240 days of age. Average lactation lengths (including suckling and milking) in MIX and DY60 group were similar (171.21 ± 5.40 and 168.36 ± 4.87 days, respectively). Differences between MIX and DY60 group in commercial milk yield (103.25 ± 7.93 and 63.59 ± 5.41 kg, respectively) and milk fat yield (5.88 ± 0.64 and 3.62 ± 0.31 kg, respectively) were highly significant (P < 0.001). Growth performance of lambs was similar in both groups (P > 0.05), however, male lambs were heavier and grew faster than female lambs until weaning (P < 0.05) and 90 days of age (P < 0.001). The effect of birth type at 210 days of age for the female lambs in MIX group was found to be statistically significant (P < 0.05) and the mean weight of single born female lambs was 40.39 ± 1.27 kg, and 41.09 ± 1.22 kg for twin born female lambs. The effects of ewe's age for female lambs in MIX and DY60 group and birth type for the lambs in DY60 group were insignificant (P > 0.05). These results show that Awassi lambs can be successfully reared in MIX suckling system and ewes produce more commercial milk than in the traditional rearing system (DY60), which offers a potential increase in economic return for Awassi sheep producers.

The freezing point (FP) was established in 48 bulk tank samples of raw and 48 samples of pasteurized goat milk that were collected in the course of lactation. Alongside, non-fat solids (NFS) content was monitored. Milk freezing point measurements were carried out using the thermistor cryoscope method in compliance with the standard CTS 570538 (1998). The mean freezing point of raw milk was found to be in an interval of -0.5513 ± 0.0046°C, variation ranged from -0.5466°C to -0.5567°C, with higher values in the spring months and a drop at the end of lactation. FP corresponded to the NFS content. The average freezing point of goat milk heat-treated on the farm to the temperature of 72°C over a period of 20 s was -0.5488 ± 0.0046°C, pasteurisation brought an average increase in FP by 0.0025°C.

A total of thirty-four Czech Fleckvieh (CF), Charolais (CH) and Charolais × Czech Fleckvieh (CH × CF) bulls with an average weight of 284 kg were included in the experiment and fed ad libitum two mixed diets: MS (based on maize silage) and LCS (based on legume-cereal and lucerne silages) with different concentrations of dietary energy until slaughter at the target live weight of 600 kg. The CF bulls consumed more dry matter (DM) of feed daily than the CH bulls (P < 0.05) and gained weight less efficiently than the CH × CF and CH animals (P < 0.01) during the entire experiment. The killing-out percentage was lower in the CF than in the CH × CF and CH (P < 0.05). The CH bulls received a higher score for carcass conformation and a lower score for carcass fatness (P < 0.01) than the CF bulls, had lower proportions of kidney and cod fat (P < 0.01) than the CH × CF and CF bulls, and produced the highest percentage of high-priced meat (P < 0.05) and the lowest percentage of separable fat (P < 0.001). The bulls on the MS diet were younger than the others at the end of the experiment (P < 0.01), gained weight more rapidly (P < 0.001), consumed less DM (P < 0.001) daily, utilized nutrients more efficiently over the entire experimental period (P < 0.001), and had a higher proportion of internal fat than the LCS bulls. It can be concluded that purebred CH bulls were superior to the other breed groups in most of the traits observed. The intensive diet based on maize silage increased average daily gains, reduced the time needed to achieve the target slaughter weight, and improved the feed efficiency of bulls.

In an experiment with three strains of Dominant genotype the effect of oviposition on egg quality characteristics was investigated. Laying hens of the Blue strain (group 1), Plymouth Rock (group 2) and their F1 cross (group 3) from 20 to 64 weeks of age were housed on litter (9 birds per m2). The collection time was at 6.00, 10.00 and 14.00 h. Eggs were gathered in a 28-day interval, every two days all produced eggs (720 eggs in total). The time of oviposition was influenced by genotype. The highest number of eggs was collected in the Plymouth Rock strain at 6.00 (53.5%) and the lowest in the Blue strain at 14.00 (11.1%). There were interactions between the time of oviposition and genotype in egg weight. Eggs laid in the morning at 6.00 were significantly heavier (60.5 g, 64.9 g and 62.1 g) in comparison with eggs laid in the afternoon (59.3 g, 62.4 g and 62.7 g). The heaviest eggs were produced by the Plymouth Rock strain. Significant interactions were observed in eggshell weight when the heaviest eggshell was in afternoon eggs (5.6 g, 5.8 and 5.9 g) and F1 genotype. The egg shape index was also affected by the genotype and time of oviposition. Among the albumen quality characteristics only Haugh Units were influenced by genotype and significantly higher numbers were determined in the Plymouth Rock strain (85.0, 85.3 and 84.7). The genotype significantly affected also the yolk index which was the highest in F1 genotype (45.4%, 45.4% and 44.5%).