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The exclusive pre-selective effect of BLAD carriers reproducing in the exposed Holstein-Friesian cattle population prompted to search for the candidate gene variants of high quality of milk performance traits within the bovine ITBG2 gene or loci linked with bovine ITBG2 gene. Theoretical considerations indicated that the &Idquo;silent mutation" C→T localized at the position of 775 bp of the gene encoding the CD18 subunit might be a potential QTL marker of high milk productivity. An association study between the polymorphism of SNP 775C>T, and the diversification of milk performance traits was carried out on the progeny of four bulls with genotypes BL/TL and 775C/T and one bull with genotypes TL/TL and 775C/T. The results documented statistically significant differences in the protein content percentage of milk in two half-sib families of bulls with BL/TL and 775C/T genotype and one half-sib family of bull with TL/TL and 775C/T genotype. It was further concluded that the polymorphism of SNP 775C>T was found to be a more efficient QTL marker than that of D128G, since in all the analysed milk performance traits for half-sib families higher values of the F coefficient were obtained for the SNP 775C>T mutation in comparison with D128G.

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.

An experiment was conducted to determine effects of wheat bran (WB) phytase on production performance and nutrient utilization in laying hens. Three hundred and seventy-five Lohmann hens at 32 weeks of age were randomly allotted to treatments of fifteen hens per pen with five pens per treatment. Five experimental diets were formulated. Diet one (control) contained 0.19% inorganic phosphate (Pi) from dicalcium phosphate. On the basis of diet 1, diet 2 and 3 were formulated to contain WB 5% and 10%, respectively. In diet 4 and 5, the WB was fixed at the level of 10% with Pi level adjusted to 0.14% in diet 4 and completely replaced with 500 U/kg microbial phytase in diet 5. The results showed that treatment three improved egg yield (P = 0.142), feed conversion ratio (FCR) (P = 0.011), utilization of crude protein (CP) (P = 0.060) and total phosphorus (tP) (P < 0.001), and serum Pi concentration (P = 0.016) compared with the control. Ten percent of WB replacing 0.05% Pi did not influence either egg yield or nutrient utilization. Compared with the control, treatment five improved FCR (P = 0.011) and utilization of CP (P = 0.060) and tP (P < 0.001), but did not influence either performance or serum parameters. The current study suggests that wheat bran could be used successfully in laying hen diets and wheat bran and microbial phytase supplemented together could replace inorganic phosphate completely.

The aim of this study was to investigate milk flow patterns and milk composition in relation to pre-milking udder stimulation. The milk of one quarter of each of the sixteen cows was removed separately and in the course of milking it was divided into six fractions (P cisternal milk during milking without stimulation and the first 300 ml during milking with pre-stimulation, 0-25%, 25-50%, 50-75%, 75-100%, 75-100%, MS-machine stripping) and into five portions (25%, 50%, 75%, 100%, 100% + MS). Two milkings were performed during two consecutive evening milkings with or without manual stimulation. Pre-stimulation resulted in a reduction of milking time, duration of the increase and decline phase of milk flow, stripping yield, but it increased the peak flow rate as compared to milking without pre-stimulation (P < 0.05). In both fractions and portions the content of fat increased steadily during milking and reached a maximum at MS. Lactose increased from P to 50-75% and then it decreased to MS. Significantly higher fat contents at 25% and 50% portions and in both protein and dry matter at 25% portions were found during milking with pre-stimulation as compared to no stimulation (P < 0.05). The content of fat, protein and dry matter were also higher in both P and 0-25% fractions for milking with pre-stimulation (P < 0.05). Pre-stimulation positively influenced the parameters of milk flow and therefore the efficiency of milk removal and contributed to better distribution of components in milk fractions during milking.

This experiment investigated the effect of olive cake in the feed of weaned Pramenka lambs on their daily gain, carcass traits and on the chemical composition of different groups of muscles. For that purpose, 45 male lambs were divided into three groups with 15 lambs each and fed separately for 50 days. The first group (control) was fed a commercial concentrate, while the second and third (test) groups were fed a concentrate with the addition of 15% and 30% olive cake, respectively. The results showed that the high level of olive cake inclusion (30%) decreased (P < 0.01) daily gain, final weight, empty carcass weight and (P < 0.05) dressing percentage of lambs. The olive cake resulted in a significantly higher (P < 0.01) proportion of stomach and intestines in the carcass compared to the control. The content of fat, proteins and dry matter in all the analyzed groups of muscles was lowest in the carcasses of lambs fed olive cake. The results of this research suggest that the addition of 15% of olive cake to the concentrate had no significant negative effect on daily gain, carcass weight and dressing percentage of lambs.

The object of an experiment was inorganic and organic forms of zinc, copper and manganese applied in mineral mixtures to dairy cows. The experiment was carried out on 90 cows with average milk yield for previous lactation of about 9 500 kg milk. The cows received mineral mixtures containing inorganic or organic forms of zinc, copper and manganese for 6 weeks before calving and during the first three months of lactation. The application of microelements as bioplexes in amounts covering 30% of daily requirements of cows had a positive effect on an increase in colostrum dry matter content from 20.9 to 23.35% as well as on the concentration of protein and fat, and the level of minerals - calcium, phosphorus, magnesium, zinc and copper. In cows' milk in the 2^nd and 3^rd month of lactation there were no differences in contents of minerals. However in the blood serum of cows in the 1^st and 2^nd month of lactation an increase in calcium concentration from 1.96 to 2.14 g/kg was observed while the content of phosphorus also increased average from 1.76 to 2.22 g/kg in the first trimester of lactation.

An evaluation of the linear description of type in 494 horses of the Old Kladrub breed for 32 traits was used to analyse the effect of variety, stud, sex, year of birth and age at description. A linear model with fixed effects was used. The highest coefficient of variation was calculated for the forelimb side-view (40.14%), chest girth (36.25%) and height at withers (30.97%). 28 out of 32 traits were in the range from 7 to 9 utilized scores. The descriptor used a very high number of scores of the scale. Significant differences between both varieties were found in 13 out of 32 traits. Significant differences were found in 12 out of 32 traits between the Kladruby stud farm and the private studs. There is no reasonable explanation of this fact. A significant variety × stud interaction was recorded in only 7 traits. Significant differences between stallions and mares were recorded in a large number of front and body traits (in 11 out of 18 traits) and in 2 rear traits. Despite of a remarkable number of significant differences between the years of birth (in 18 out of 32 traits) and age at description (in 13 out of 32 traits) both factors are not the important ones for the selection of horses according to the type traits. The description of type traits, performance recording and selection are carried out in the population of four-years-old horses born in the given year. The age at description does not play a role because all horses are now described each year at a standard age of four years. The linear description of type is an important tool for the breeding and conservation of genetic diversity within the breed.

The aim of this study was to determine the influence of MHS-genotype and feeding regime on the growth and development of muscle and fatty tissue in the whole body as well as in hams of hybrid pigs. The experiment was carried out on 72 barrows that were divided into 4 groups regarding the MHS-genotype (NN and Nn) and feeding regime (standard and intensive). Data necessary to determine the volume of examined tissues were obtained by means of magnetic resonance tomography. During the fattening period there were no statistically significant differences between pig groups with respect to total lean content of the body although the feeding regime effect in the finishing fattening phase was on the margin of statistical significance (P = 0.057). Differences between investigated groups with respect to the lean content in hams were not significant either. Results of this research lead to a conclusion that different feeding regimes and MHS genetic status of pigs do not have a significant influence on the growth of muscle and fatty tissue in hams.

Processing of milk for higher value-added products and milk food chain safety require prevention of higher occurrence of microorganisms that can produce spores. It is important to carry out prevention already during raw milk production by farm hygienic measures. The above-mentioned microorganisms can jeopardize the quality and safety of milk foods. This is the reason why the knowledge of factors, interrelationships and possibilities of milk contamination is assumed. The occurrence of hygienically important groups of microorganisms in mixed rough fodder (F) in feeding trough, in excrements (E) and in bulk milk (M) was investigated on seven farms with a good level of milk yield, management and hygienic conditions for three years in summer (S) and winter (W) feeding seasons. The data set was well balanced in terms of other possible farm factors (such as height above sea level, breed of dairy cows and so on). In total 70 samples of each mentioned material were collected. The investigations were focused on counts of thermoresistant bacteria (TRB), total counts of bacilli (TBA), frequency of occurrence of Bacillus cereus (BCE) and Bacillus licheniformis (BLI), and counts of other bacilli (OBA) in all mentioned materials and on the frequency of occurrence of main mastitis pathogens Streptococcus agalactiae (SAG) and Staphylococcus aureus (SAU) in milk. The means of parameters did not exceed the defined standard limits, in particular in raw milk that was suitable for direct human consumption in raw state or for processing for milk products without heat treatment according to relevant EU food legislation. The variabilities of hygienic parameters were relatively high: from 179% (TBA) to 315% (TRB) in F; from 178% (BLI) to 350% (TRB) in E; from 117% (TBA) to 459% (SAG) in M. S increased TRB in F (P > 0.05). Counts of bacilli were well balanced between S and W. S increased BLI in E (P < 0.05), an opposite trend was observed in BCE. The season did not influence SAG and SAU in M. Higher (P ≤ 0.01) counts of BCE were in S, the trend was opposite for BLI (P ≤ 0.05). The season effect on the occurrence of technologically and hygienically difficult microorganisms was not confirmed in general for M, F and E of dairy cows. Regression analysis of the investigated parameters was done. There were significant positive correlations between bacilli and TRB in F as well as in E (correlation coefficients from 0.32 to 0.65; P ≤ 0.01). The relationships between TRB and occurrence of bacilli in M were less close (0.30; P ≤ 0.05) than in F and E. No significant relationships were found between TRB and occurrence of main mastitis pathogens in milk (SAG r = -0.14 and SAU r = 0.11; both P > 0.05). It confirmed the high pasteurization efficiency at liquidation of mentioned pathogens. The relationship SAU × SAG in M was 0.23 (P < 0.05). It suggests a simultaneous effect of dairy cow health state on the occurrence of both pathogens. The majority of significant relationships (from 0.26 to 0.76; from P ≤ 0.05 to P ≤ 0.001) was in F × E within TRB, BLI, OBA and TBA. 7% to 58% of the changes in E were dependent on changes in F. The occurrences

The objectives of this study were to assess post-hatch development of chickens treated in ovo with the aromatase inhibitor YM511. A total of 137 eggs coming from artificially inseminated hens were at first injected in the albumen with either DMSO alone (54 eggs injected, control group) or with DMSO + aromatase inhibitor (YM511, 1 mg/egg, 83 eggs injected, treated group) and then incubated under standard conditions. Out of the 24 chicks hatched in the treated group, 16 were genetic males (ZZ) and 8 were genetic females (ZW). By 26 weeks of age, secondary sex characteristics of females (cloaca, comb, wattles, song, feathers of hackle and tail) progressively transformed into a male phenotype. Using CT-scanner technology in these 8 birds, the presence of irregular testis-like masses positioned in the antero-ventral portion of the kidneys was observable, an indication that reproductive organs had also been affected by the treatment.

Feeding selectivity of Nile tilapia (Oreochromis niloticus L.) juveniles (9.3-20.9 g) to four aquatic macrophyte species and tilapia growth were studied in 4 consecutive experiments. Plant diet was provided to 8 tanks containing 20 fishes for 5 days. The fish were fed a carp diet between 4 experiments for 14 days. The consumption of 4 aquatic macrophyte species differed significantly [F(3,252) = 39.6; P < 10^-6]. Elodea canadensis was the most preferred plant (Chesson selectivity index = 0.50 ± 0.05, n = 4). Potamogeton pectinatus and Spirodela polyrhiza were consumed with about equal preference. Myriophyllum spicatum was the least preferred species. Elodea canadensis contained relatively more phosphorus, potassium and ash than the other three species. The daily plant dry weight intake ranged between 0.79 and 2.26% of body weight. The fish grew during the first two experiments (SGR = 2.54 and 3.18%/d, respectively), but lost weight during the 3rd and 4th experiments (SGR = -1.75 and -1.71%/d, respectively).

We performed intensive rearing of larvae of the nase Chondrostoma nasus (L.) in a feeding experiment until 21 days from the initiation of exogenous nutrition under laboratory conditions at a temperature 26°C. Two dry starter feeds (a feed for salmonids and a starter feed of the artificial plankton type) differing in the composition of nutrients (50% and 60% of proteins, 12% and 16% of fat, respectively) and natural food (Artemia salina nauplii) were used. Cumulative survival rate, individual weight (w), total length (TL), specific weight growth rate (SWGR), specific length growth rate (SLGR) and condition factor (CF) were assessed. One-way analysis of variance (ANOVA) was used for statistical processing of data. High survival rate 99.3% and the highest (P < 0.01) growth rate of nase larvae (TL = 22.0 mm, w = 69.2 mg) were found when feeding the natural food. The application of dry feed of the artificial plankton type resulted in higher survival (98.8%) and significantly higher (P < 0.01) growth of both length and weight (TL = 17.5 mm, w = 42.5 mg) compared to the nase fed with dry feed for salmonids (survival rate 77.3%, TL = 15.9 mm, w = 24.5 mm). In the course of the experiment the value of Fulton’s coefficient increased from initial 0.57 to 0.79 in fish fed with artificial plankton to 0.65 in fish fed with natural food and to 0.61 if dry feed for salmonids was used. We conclude that with an appropriate starter feed the successful intensive rearing of larval nase can be carried out under controlled conditions.

In vitro study of the rumen fluid (RF) and hindgut content (HC) fermentation by microbiota taken from sheep grazing in an area atmospherically polluted from the non-ferrous metal industry was conducted and compared with controls from an uncontaminated area (UA). The experimental sheep were exposed to the prolonged intake of heavy metals by grazing in the contaminated area (CA) for one year. Soil and grass from that area and the rumen content of sheep were analyzed for heavy metal levels. Based on the levels of mercury (4.752 mg/kg), copper (232.9 mg/kg), cadmium (1.167 mg/kg), lead (92.509 mg/kg) and arsenic (74.59 mg/kg) the soil was categorized as profusely contaminated. Meadow hay (MH) from UA was used as a tested substrate of fermentation activity; it was incubated with buffered RF and HC inocula from CA and UA for 24 h. The gas volume in CA was significantly decreased by 50 and 36% in RF and HC, respectively. The methane production in CA was significantly decreased by 77 and 71% in RF and HC, respectively. The significantly decreased values of the fermentation parameters in CA in comparison with UA were accompanied by the reduced (P < 0.01) total concentration of rumen ciliate protozoa.

The aim of this study was to investigate an association between aggressiveness and high level of feeding in a half-open feedlot production system. An experiment was conducted on 72 head of beef cattle of different breeds. The animals were at about 10 months of age. Medium quality silage was offered ad libitum and supplemented with high (HE) and low level (LE) of barley (2.5 and 1.5 kg/day/head, respectively) and supplemented without (nil) or with (+) extracted soybean meal (0.45 kg/day/head). Several types of animal behaviour were observed such as those parameters that are categorized to be main aggressive behaviours, butting, being butted, mounting and being mounted. Significant differences (P < 0.05) were found in butting, being butted behaviours between HE and LE treatment groups. Mounting and being mounted behaviours were significantly different (P < 0.05) in steers and heifers and between the seasons as well. Steers performed more incidents of mounting behaviour than heifers and it was the same for spring, during which animals had more mounting behaviours. It was concluded that there was a close relationship between high-energy diets and aggressive behaviour, which necessitates some management measures to be taken in order to ensure better animal welfare and beef production.

Two-year data from terminal study conducted to evaluate post-weaning growth and carcass traits of Texel, Suffolk and Columbia sired offspring were used to evaluate the effect of breed on cultural energy expenditure of lamb production. Each year whiteface ewes (n = 82) composed of primarily Polypay × Dorset ewes were exposed to Texel, Suffolk or Columbia rams for 35 days in the breeding season. The ewes were wintered outdoors on average-quality lucerne hay according to NRC (1985) requirements and were not provided any concentrate during late gestation or lactation. A total of 279 lambs were born with an average of 1.7 lambs per ewe and weaned lambs were used in the study. The lambs were weaned on average at 70 days of age and lambs from each sire breed were placed either in feedlot or on pasture. Texel and Suffolk sired lambs had higher weaning weight than Columbia sired lambs (P < 0.01). Lambs in the feedlot were fed shelled maize and pelleted protein supplement. Lambs on pasture grazed for 63 days and received 455 g concentrate daily and later they were placed in the feedlot. For the cultural energy analysis, pasture establishment and maintenance, feed in feedlot and on pasture, transportation, labour, machinery, electricity and other inputs were calculated and corresponding values for each input were obtained from literature. It was assumed for the analysis that 20 percent of ewes were culled and lambs sold after weaning were included in the analysis. Texel and Columbia breeds had a higher energy input per kg live weight than Suffolk breed (P < 0.04). There was no difference between breeds in terms of energy input per kg carcass (P > 0.4). Suffolk breed had a lower cultural energy ratio for the protein energy output than Columbia and Texel breed (P < 0.02). Energy output ratio defined as kjoule input/kjoule output was better for Suffolk breed and it was different from that of Columbia and Texel breed (P < 0.03).

A total of 1 200 broiler breeder eggs were collected from a commercial flock at the hen age of 37 weeks and divided into storage treatments of 5 and 15 days. Prior to storage, the eggs were further divided into pre-storage incubation (PRESI) 0 (control), 4 and 8 h treatments. Eggs in the 4 and 8 h PRESI treatment were incubated at a standard dry-bulb temperature of 38.0°C. All eggs were weighed prior to and after storage, then incubated in a commercial setter and hatcher for 21 days. After the incubation, all unhatched eggs were opened to determine fertility, hatchability and embryonic death. The 4 and 8 h PRESI treatment significantly decreased hatchability results of long-term stored eggs compared to non-heated eggs. Hatchability results of eggs stored for 5 days were significantly better compared to eggs stored for 15 days. Subsequent growth performance of progeny was not significantly affected except for the main effect of egg storage on feed conversion. There were significant PRESI × egg storage interactions for apparent fertility, hatchability of total and fertile eggs and embryonic mortality. It was concluded that the PRESI treatment did not have a detrimental effect on the hatchability of broiler breeder eggs stored for 5 days and it might even increase hatchability while it had a detrimental effect on the hatchability of broiler breeder eggs stored for 15 days.

Live body measurements of weight, height, length, girth, stifle- and hip-width and a measure of muscularity (ratio of stifle to hip width) were monitored on 258 Yankasa sheep stratified into age categories of 1 to over 3 years determined mostly from records and partly by dentition. These animals are from purebred Yankasa sheep kept as a part of the open nucleus-breeding scheme of the National Animal Production Research Institute, Shika, Zaria, Nigeria. The effect of sex, type of birth and age group of lambs on live measurements and muscularity were analyzed by least-squares procedures. All variables examined, except sex, had significant (P < 0.001) effects on all body measurements. At birth, male and single-born lambs were significantly heavier than female and twin-born lambs. At early age, most factors significantly (P < 0.01) influenced the body weight, body dimensions and muscularity traits with single-born lambs being 31% heavier, 10% taller and 11% bigger in girth; more highly muscled than the twin-born lambs. This advantage of male over female born lambs (except in hip-width and girth) for growth and developmental traits was maintained reasonably well to the advanced ages. All phenotypic correlations between body measurements were positive and significant (P < 0.001). The highest correlation coefficient was found between chest girth and body weight. The polynomial equation using chest girth as an independent variable predicted body weight more accurately as compared to the linear equation.

The quality of produced milk and piglet growth were investigated in three groups of lactating Large White sows fed three mixtures containing different levels of lysine, threonine and crude protein. Piglets were weighed immediately after delivery and then in weekly intervals. At the age of 21 days the litter weight was the highest in group B (67.96 kg; P < 0.05), i.e. in the group with the highest dietary content of amino acids. Milk from lactating sows was sampled and analysed. An increased level of dietary amino acids became evident in milk at the first milk sampling (i.e. three days after delivery), when the content of lysine and threonine in milk was significantly the highest in group B (lysine 11.96 g/16 g N; threonine 6.72 g/16 g N; P < 0.05). The level of amino acids in milk and the differences between groups diminished in the following samplings. The changes of crude protein in milk were similar.

Two experiments were conducted to investigate the effects of dietary crude protein level and degradability on milk urea nitrogen (MUN) content. In experiment 1, twelve multiparous lactating cows averaging 176 days in milk were divided according to DIM and milk production into three 4 × 4 Latin squares with four 2-week periods. Cows were fed four diets with different crude protein levels (13.0, 14.0, 15.0, and 16.0%, DM basis) with isocaloric, respectively. Crude protein levels had a low effect on milk yield and composition (P > 0.05), but a significant effect on MUN content. There were significant differences in the MUN content of cows fed either of the two diets (P < 0.01). In experiment 2, fifteen multiparous Holstein dairy cows averaging 91 days in milk were classified according to DIM and milk production into five 3 × 3 Latin squares with three 3-week periods. Cows were fed one of the three isocaloric and isonitrogenous diets with RUP being 30.8%, 36.2%, and 41.6% (CP basis), respectively. Milk yield, milk composition, and MUN content were not significantly affected by protein degradability, and there were no significant differences between any two dietary treatments (P > 0.05). These results indicated that MUN might be used as a parameter to monitor the change in dietary protein levels.

Artificial reproduction with and without hormonal treatment was performed in females of the common gudgeon (Gobio gobio L.) to assess the suitability of this cyprinid species as a fish model for embryo-larval cytotoxic tests. Considering sperm immobilisation tests, the solution for tench was utilizable. The clearing solution designed for the observation of embryonic development in the European catfish was also found suitable for the common gudgeon embryos. The egg and embryonic mortality, embryonic development, hatching and survival rate were examined. Ovulation occurred in 89% of females after the application of the carp pituitary (5 mg/kg) but embryonic mortality reached nearly 100%. The highest embryonic mortality in females with hormonal treatment was observed within 24 hours of development. On the other hand, the reproduction of females without the application of hormonal stimulation was nearly completely successful with mean mortality 60%. The hatching of embryos of females without hormonal stimulation occurred (average values) 71 hours after fertilization and lasted 65 hours. Embryonic development finished within 176 hours. Our pilot study demonstrated that the eggs of common gudgeon were suitable for embryo-larval tests from the 7^th to the 8^th embryonic developmental stage.

Genetic distances were studied among Czech Red cattle, German Red, Czech Pied, Polish Red, Czech Black and White, and German Black and White cattle. DA genetic distances were calculated, and trees were constructed using the neighbour-joining method. Evaluating the genetic distances by microsatellites, the lowest value was between Czech and German Black and White breeds. A surprisingly high value was found between Czech and German Red breeds, and the highest values between German Red breed and both German and Czech Black and White populations came up to expectations. In the phylogenetic tree made using microsatellites, the German and Polish Red breeds clustered, but Czech Red breed was not joined with them. The other cluster was obtained for Czech Black and White and German Black and White. The tree made of protein markers differed slightly. Because the populations of Czech and German Red breeds are small and also because of organizational issues, the common protection of Central-European red populations and breeding them as a gene pool are recommended.

This research was carried out to determine the effect of Jerusalem artichoke (JA) with or without 5, 10% vetch (V) supplementation on performance, egg quality characteristics and egg cholesterol content. In the study, seventy-five 25 weeks-old commercial white laying hens were randomly divided into one control and 4 treatment groups each containing 15 hens. Control group was fed basal diet without JA or V. Treatment group 1, 2, 3 and 4 were fed diets containing 5% V, 5% JA, 5% JA + 5% V and 10% JA + 10% V, respectively. The feeding period lasted 16 weeks. In the study, it was determined that dried-ground JA contained dry matter, crude protein, ether extract, crude fibre, crude ash, inulin and metabolizable energy (ME) at the level of 93.30, 10.02, 0.36, 5.64, 9.05, 15.80% and 3 060 kcal/kg, respectively. At the end of the study, live weight was lower by 4.36-10.09% in the treatment group 10% JA + 10% V compared with the other groups, but feed efficiency was improved in this group. There were statistically significant differences between the groups in egg quality characteristics (P < 0.05, P < 0.001). Egg production was not affected by supplementation of 5, 10% JA with or without 5, 10% V supplementation. Egg yolk cholesterol and total cholesterol content were not different in the groups (P > 0.05). As a result, the addition of JA with or without V has no adverse effect on performance and egg quality in hens.

Breed effects on live weight gain, slaughter characteristics and carcass composition were compared in Aberdeen Angus, Charolais, Hereford and Simmental bulls. The experiment extended over 2 years and involved totally 96 animals. The target slaughter live weights were determined 550 kg for earlier maturing breeds Aberdeen Angus and Hereford and 630 kg for later maturing breeds Charolais and Simmental. Charolais and Simmental gained more rapidly (P < 0.05) than Aberdeen Angus while Hereford were intermediate. Hereford had lower (P < 0.05) dressing percentage than the other breeds. Percentages of grade I meat were significantly higher (P < 0.05) in Charolais and Simmental. The highest percentage of separable fat was recorded in Hereford (P < 0.05). Charolais and Simmental had lower (P < 0.05) thickness of subcutaneous fat over MLLT than Aberdeen Angus andHereford. The later maturing bulls generally tended to achieve higher live weight gains during the experiment, produced less fat and had higher percentage of meat from high priced joints in comparison with earlier maturing animals.

The effect of dietary supplementation of selenium in an organic form on performance, carcass traits and selenium content in tissues of broiler cockerels Ross 308 was studied. The soya-wheat-maize diet contained 50 mg vitamin E/kg. The experiment was conducted on 810 straight-run broiler cockerels randomly divided into 3 groups: group I - control, without selenium supplement; experimental group: II - 0.3 mg Se/kg, Se-enriched yeast was applied as a Se source; III - 0.3 mg Se/kg, Se-enriched alga Chlorella as a Se source. The broiler chickens were slaughtered at 42 days of age. In performance traits higher (P ≤ 0.05) live weight of broiler chickens was recorded in the experimental groups (II - 2 430.6 g and III - 2 425.2 g). There were no significant differences between the groups in feed conversion and mortality. Se-enriched alga had the best feed conversion, and selenium supplementation slightly increased mortality in both experimental groups. No significant differences between the groups were found out in carcass traits and dressing percentage. The content of selenium in breast and thigh muscle, feathers and excrements increased (P ≤ 0.05) in both experimental groups compared to the control group. Higher values in breast and thigh muscle and in feathers were measured in the group supplemented with selenium from Se-enriched yeast, also in comparison with the group supplemented with selenium from Se-enriched alga Chlorella. The broiler chickens receiving Chlorella had a higher (P ≤ 0.05) selenium content in excrements compared to the group with Se-enriched yeast. The selenium concentration in liver was higher (P ≤ 0.05) in both experimental groups compared to the control. The supplement of selenium from Se-yeast and Chlorella in the diet for broiler chickens increased the microelement concentration in muscle.

A total of 36 samples of feed - 19 samples of hays and 17 samples of silages were used for estimation of in vivo and in vitro digestibility. The organic matter digestibility (OMD) was estimated by in vivo and two in vitro techniques (method of Tilley and Terry and two-stage pepsin-cellulase method (Pepcel)). The regression equations were calculated from the results obtained in the experiment. Tilley and Terry method provided consistent results of OMD estimation for both the groups of roughages: in vivo OMD = 14.7 + 0.782 × [Tilley and Terry] (n = 18; R² = 0.76); in vivo OMD = 36.3 + 0.513 × [Tilley and Terry] (n = 16; R² = 0.75) for hays and silages, respectively. Different accuracy was found out in Pepcel method: in vivo OMD = 37.0 + 0.478 × [Pepcel] (n = 19; R² = 0.49); in vivo OMD = 37.8 + 0.484 × [Pepcel] (n = 17; R² = 0.87) for hays and silages, respectively.

The effect of environmental conditions on hatching indices of poultry eggs is sufficiently important that new methods for their improvement are sought, among others through exposing the eggs during hatching to an artificially generated magnetic field of variable frequency. Hatching eggs in this study came from Pharaoh quail in the 4th month of laying. The flock was kept under optimum microclimate conditions and fed a complete feed mix containing 21% total protein and 11.7 MJ ME. The eggs (n = 150), after weighing, were divided into 3 groups equal in respect of numbers: control (I) and two experimental (II and III). The eggs of group II and III were exposed to the action of variable magnetic field of the same intensity but different times of application. The highest percentage of dead embryos during incubation in relation to fertilised eggs was found in control group (11.36%), while the smallest was from group II (4.17%). The highest value of hatching indices calculated in relation to fertilised eggs was found in group II (91.6%), while the smallest was in group III (83.7%) with 86.3% in control group. The results point to the possibility of increasing egg hatchability indices through the use of additional variable magnetic field. The chicks hatched from eggs exposed to the action of this experimental agent had similar body weight. The average weight of one-day-old chicks ranged from 7.82 g (group II) to 8.05 g (group III). In the last week of rearing, mean body weight in both sexes was similar and ranged from 168 (group I) to 172 g (group III) in males, and from 186 g (group I) to 199 g (group III) in females; these differences were not statistically significant. The females of group III reached sexual maturity at 41 days, this being one and three days (non-significantly) earlier than birds in group I and II.

The effect of some factors (genotype, sex, litter size, age of dam at lambing, month of lambing and year of birth of lamb) on the growth of lambs - crossbreds between the Improved Wallachian (IW) and East Friesian (EF) breed was evaluated in operating conditions during two successive years. Three genotypes were evaluated: IW 50 EF 50, EF 75 IW 25 and EF 87.5 IW 12.5. The evaluation of the effect of genotype on growth showed that this factor did not have a significant effect on the majority of growth traits under study. In the period from birth to 100 days of age the highest daily gain was found in IW 50 EF 50 (263 g). The daily gains of EF 75 IW 25 and EF 87.5 IW 12.5 in this period were lower but identical (244 g). Age of dam had a significant effect on the majority of growth traits under study. Sex of lamb had a significant effect on body weight at 100 days of age and also on the majority of daily gains under study. The factors litter size, month of lambing and year of lamb birth were the most significant sources of variation of daily gains. As far as the non-genetic factors were concerned, the highest daily gains from birth to 100 days of age were recorded in males (259 g), in singles (260 g), in lambs from 4-years-old ewes (269 g), in lambs born in January (263 g) and in lambs born in the first year of evaluation (256 g). The analysis of phenotypic correlations indicated that body weight at birth showed a positive and highly significant (P ≤ 0.01) effect on the majority of growth traits under study. All phenotypic correlations between individual body weights were positive and high (P ≤ 0.01). The majority of phenotypic correlations between individual daily gains under study were also positive and high (P ≤ 0.01).

The objective of this paper was to obtain information about the effect of interactions and different agronomical measures on autumn saved herbage of different sites in Central Europe (Czech Republic, Germany, Hungary, Poland). Within the different sites, the effect of the factors pre-utilisation (accumulation since June, July or August) and winter harvest date (November, December or January) on dry matter (DM) yield and digestibility of organic matter (DOM) was investigated over three consecutive years. All results were examined by analysis of variance and least-significance differences (LSD) were calculated (with P < 0.05). For all years, date of winter harvest was the most important source of variance. The highest yields were attained in November (varied from 2.3 to 0.8 t/ha), the lowest in January (from 1.5 to < 0.2 t/ha). The highest DOM concentration (from 70.4 to 52.4% of dry matter) was reached in November, and it decreased until January (from 59.6 to 35.2% of dry matter). Predominantly caused by the prevailing climatic conditions, the DM yields of the sites varied considerably during winter, showing a significance for the interaction winter harvest date × site as well as for the factor site. The utilisation of autumn saved herbage, pre-utilised in July, might be the best opportunity providing an adequate quantity and DOM for suckler cows until the end of the year, but the prevailing climatic conditions at different sites inCentral Europe finally decide on the practicability of winter grazing.

The aim was to determine the conversion of alimentary substances of laying hens (nitrogen, phosphorus, potassium) into the production of eggs and to determine the emission of nitrogen, air pollution by dust and microorganisms in accordance with different technologies of layer rearing. The studies were conducted in 6 poultry houses. The birds were kept in premises in cage batteries BKN-3, "Spech", OBN-1, OBN-3 or on littered floor. It was found out that there was 1.6 times more dust in the air of poultry house where laying hens were kept on litter and the total number of bacteria was 2.4 times higher than in the bird cages (P < 0.001). The laying hens assimilated 21.95-28.42% of nitrogen, 19.63-31.25% of phosphorus, 6.04-8.33% of potassium for egg production and weight gains when feed is balanced. If cage technologies are applied, over a year, there is a loss of 6.7 ± 1.4% of nitrogen through the excrements because of nitrogen emission. When the technologies of littered floor are used, there is a loss of 18.5 ± 4.8% of nitrogen extricated with the excrements (P < 0.025). When the birds were kept in cages, 0.059 ± 0.011 kg of nitrogen per each bird evaporated because of ammonia emission, while in the case of littered floor - 0.227 ± 0.126 kg of nitrogen.