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The aim of the study was to find a period with a significant influence on the ratio of individual muscle fiber types, based on correlation analysis and intensity of pig growth and age. The test was carried out with the use of 72 animals (balanced sex – gilts/barrows) of the Danbred genotype and weight extent of 25-115kg. Pigs were fed ad-libitum (according to the body weight) by complete feed mixtures A1, A2, A3. The growth intensity in relation to the muscle fiber characteristics was evaluated, based on the average daily gain (ADG) observed during four different age periods, determined as follows: period A 70-84 days, period B 85-105 days, period C 106-134 days and period D 135-154 days. Following the slaughter the muscle fiber parameters (diameter and perimeter) and typology (the percentage of individual types of muscle fibers – I, IIA and IIB) were determined based on the analysis of samples obtained from the m. longissimus thoracis et lumborum (MLLT). The period A and C showed significant positive correlations (P <0.001), where with increasing ADG the proportional share of type I muscle fibers increased, while the share of muscle fiber types IIA and IIB decreased. The period D demonstrated a positive correlation (P <0.001) between the change of ADG and proportional share of the slow glycolytic fibers IIB.

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Chromium is an integral part of the biochemical processes of carbohydrates, lipids and proteins. It works like a coenzyme in organism as well as it increases the efficiency of the insulin and the connections to the individual receptors or target cells. It also helps to control the transmission of the glucose. Although chromium is classified as a functional questionable microelements, the results of several studies of the recent times suggest that it might in the future play an important role as a dietary supplement in nutrition of pigs. The objective of the experiment was to find the effect of the organic chromium (Cr+3) on structure of the carcase and parameters of the chemical composition muscle musculus aductor of the Large White Breed. The mineral-protein dough used in feed ration for experimental group was enriched by chromium-nicotinate, which was 0,75 mg.kg-1 in complete feed. Chromium-nicotinate was in form inactivated yeasts saccharomyces cerevisiae fermented on medium which was from natural sources with higher content trivalent chromium. In parameters of the carcass value we found statistically significant difference at P ? 0.05 in parameter % lean meat cuts in % and in parameter % thigh of weight of carcass side in %. In parameters of the carcass value we found statistically significant difference at P ? 0.05 in parameter of the weight thickness from thigh in kg and in amount of abdominal fat in kg. We found no significant differences in the groups of fatty acids in intramuscular fat in muscullus aductor.

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The aim of the study was to evaluate the effect of sex and slaughter weight on the carcass composition in barrows and gilts of the Dan-Bred genotype. The test used the total amount of 144 pigs, all within the weight range of 25-114 kg of live weight. In order to determinate the weight and carcass part proportions a slaughter dissection was carried out following the termination of the experiment. Subsequently the influence of sex and body weight on pig carcasses composition was evaluated. For the purposes of describing the influence of sex and slaughter weight on the weight and carcass parts proportions regression equations were created. Our study detected significant differences in the body composition of gilts and barrows. The final results show that gilts are on average meatier and less fatty than barrows. Gilts have a higher lean meat share in individual carcass parts as well as lower fat share than barrows. The study also found an important relationship between the live weight and the meat and fat amount in main meat parts. For each 1 kg of body weight increase the fat coverage increases as well. The increase is +0,03kg in ham, + 0.01kg in neck and shoulders and 0.04kg in the loin parts. With increasing live weight the weight of the fat coverage of all the main meat parts increases as well, while the fat coverage share increases only in the shoulder and the loin. With increasing live weight there is also a significant increase in the amount of meat contained in the individual carcass parts, however, if this trend is expressed as a proportional share based on the total weight of the carcass there was only a slight meat increase observed in the ham and the loin (i.e. the increase was observed in the more valuable parts). For the parts of the neck and the shoulder the study showed that with the increasing body weight the weight of these parts decreases. The monitored genotype shows a lower decrease of lean meat indicators as compared with the less recently published data.

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The objective of this study was to estimate the differences in fattening performance, carcass traits and meat characteristics of Prestice Black-Pied (PBP) pigs and (BuxL)x(HxPn) crossbreed pigs (C) reared under organic free-range system or conventional indoor feeding system. PBP pigs under conventional system were characterized by lower average daily gain and worse carcass traits (lower meat percentage and higher carcass fatness) compared to C pigs. In nutritional characteristic, meat of PBP pigs differed in the content of crude protein (it was lower) and in intramuscular fat content (it was higher) from C pigs. There was not found significant difference in n-6/n-3 PUFA ratio between PBP and C pigs. PBP pigs under organic free range system had a similar growth performance, lower daily feed intake and lower weight of ham in comparison with C pigs. There was found differences in nutritional characteristic between PBP and C meat. PBP pigs achieved significantly (P<0,05) higher intramuscular fat content. The content of n-3 PUFA was higher in meat of PBP pigs than in C pigs. In the both organic and conventional farming systems, PBP meat had lower content of hydroxyprolin which is accompanied with shorter duration of maturing time. The aim of this evaluation is to find out the optimal rearing system for Prestice Black – Pied pigs. The most PBP population is reared under conventional indoor system and its pork products are sold as conventional. In these conditions, PBP breed can not compete with the modern pig breeds and final hybrids in growth and carcass characteristics. It can be concluded that the organic free range system is much suitable for BPB breed than commercial rearing system. The organic system allows better expression of PBP genotype. This production system with the use of local breed could produce specific and high-quality products with the regional label.

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The objective of the experiment was to determine the effect of natural substances as a potential substitute for antibiotics in the boar extender on the semen survival time. Thirteen natural substances were tested. Natural substances were dissolved in 4% DMSO with a minimum bactericidal effective concentration of between 300 and 4,800 µg/ml. The control sample was diluted with a semen dilution ratio of 1:1 in a BTS extender without antibiotics. Sperm motility was evaluated at 0h, 1h and 24h after semen dilution. The best sperm motility was only recorded at thymol 25 % and carvacrol 40 % after 24h storage time. Other tested natural substances had sperm motility between 0 and 5 %. The sperm motility was significantly decreased over the storage time for all the tested natural substances (P < 0.01). Results of the present study indicate a negative effect of the concentrations of tested natural substances on boar semen survival time. At present, practical utilization of the natural substances we tested as a potential substitute for antibiotics in boar semen extenders is not possible owing to its reduced sperm motility.

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The experiment was based on feeding the organic and inorganic forms of selenium and the assessment of their effects on the laboratory values of the ejaculate (total count of sperm, sperm motility, ejaculate volume, sperm concentration and per cent of pathological sperm) in breeding boars. The experiment involved 78 boars divided into four equal groups. The individual groups received feed mixtures with the supplement of 0.3 and 0.6 mg Se/kg of feed mixture in organic form, and 0.3 and 0.6 mg Se/kg of feed mixture in inorganic form. The experiment lasted 20 weeks, during which the average daily temperature was 21oC. In the last 30 days of our study the boars were exposed to higher ambient temperatures. The selenium supplement significantly decreased the sperm concentration in boars supplemented by 0.3 mg Se/kg of feed mixture (P < 0.01) in inorganic form; this group of boars also had a lower total count of sperm produced (P < 0.01). The group of boars receiving the inorganic selenium supplement of 0.6 mg/kg of feed mixture had a lower sperm concentration (P < 0.05); however ejaculate volume increase (P < 0.01) occurred at the same time. In our experiment the groups of boars receiving the selenium supplement of 0.6 mg/kg of feed mixture in both organic and inorganic form had the most equal values of the total count of sperm produced. It can be assumed this rate of selenium is capable of eliminating the impacts of heat stress on breeding boars to a certain degree.

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A simple method for aseptic collection of more than 50 ml blood from anaesthesised adult minipigs is described. The blood is collected from vena metatarsalis plantaris or from vena metatarsalis dorsalis using a standard intravenous catheter.

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Environmental temperature is known to influence the performance of growing pigs. Pigs are quite sensitive to high temperatures and the climate changes could lead to changes in quality of meat. The aim of this experiment was to assess the effect of high temperature on meat quality characteristics on Large White breed. This trial was carried out in Experimental centre of livestock in Nitra and lasted three months. Pigs were divided into two groups; experimental group of seven pigs was housed in climatic chamber with constant temperature 30 °C. Control group of six pigs was reared in standard conditions in the pen. The experiment started when the pigs reached 30 kg and all the pigs were slaughtered according to legislation at about 100 kg. Pigs were offered diet ad libitum. The M. longissimus thoracis (MLT) and M. semimembranosus (MSM) was used to asses meat quality characteristics. Ultimate pH was recorded 45 minutes and 24 hours post-mortem and also the electric conductivity. Meat colour of samples was measured 24 hours after slaughtering and samples intended for Warner–Bratzler shear force were also evaluated. It was found that pigs influenced by high temperature had significantly lower (P?0.05) muscle pH after 24 hours postmortem in MSM (5.59) compared to pigs in standard conditions (5.67). Electric conductivity in MSM after 24 hours was significantly lower (P?0.05) in pigs housed in pen (9.75 mS-1). In conclusion high temperature had no significant effect on meat quality of pigs in parameters shear force, drip loss and meat colour.

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For consumers as well as meat industry, it is important that the meat will be in good quality. Except genetic predisposition to stress, some changes of meat quality can be caused by stress before slaughter. The aim of the experiment was assess possible influence of pre-slaughter factors on pig meat quality. The meat quality of 1980 meat hybrids of fattening pigs was evaluated. The following pre-slaughter indicators were evaluated: month of slaughter, time of loading, time of transport, time of housing, temperature during housing and time of slaughter. The meat quality was judged on the basis of the pH value measured 45 minutes after the slaughter of animals (pH1). We found out that the meat quality was influenced by month of slaughter. The highest incidence of PSE (pale, soft, exudative) meat in the MLD - musculus longissimus dorsi was found on July. The lowest average pH1 in the MLD was found out on February, it was statistically significant (P<0.05) in comparison with other month. The highest incidence of PSE meat in relation to time of loading was detected in 0, 11, 12 a.m. and from 4 to 6 p.m. In the indicator time of slaughter was found out the highest incidence of PSE meat in hours from 3 a.m. to 9 a.m. Duration of transport to the slaughterhouse was maximally 2 hours. The lowest incidence of PSE meat was found out in the groups of pigs which were housed in the slaughterhouse from 1 to 4 hours. In conclusion we can state that the meat quality was markedly influenced of per-slaughter factors.

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The aim of the research was to evaluate the effect of feeding of compound feed with the addition of organic selenium in slaughter pigs to assess the nutritional characteristics of pork and the impact of selenium-enriched pork consumption for selected health indicators of probands. As far as the results are concerned, we can conclude that there has been an improvement in the nutritional quality of pork in the total protein level of 22.32 ± 0.91 g.100g-1, in the intramuscular fat content of 2.95 ± 1.35 g.100g-1 at significance p<0.05, as well as by the lower energy value of 484.46 ± 46.63 KJ.100g-1. In the pork enriched with organic selenium the concentration was higher 1.045 ± 0.10 mg.kg-1 compared with the control group 0.701 ± 0.05 mg.kg-1 at significance p<0.001. By consumption of the enriched pork there has been an increase of the selenium concentration in blood serum of probands traced with an increase from 73.19 ± 15.68 µg.l-1 to 83.18 ± 15.13 µg.l-1 at significance level p < 0.001. In connection to increased selenium status of probands, we have detected an increase in antioxidant capacity from 1.38 ± 0.41 mmol l-1 to 1.52 ± 0.42 mmol.l-1. Pork seems to be a suitable component of a balanced diet as it is possible to increase the selenium content in its muscles and subsequently increase the selenium status of its consumers.

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The aim of this study was to evaluate the effect of rapeseed meal addition on the selected physical characteristics of pig meat and fat quality. Seventy-two pigs (DanBred)x(CLWxCL) were divided into two experimental groups according to their received diet. The control group was fed with a complete feed mixture (CFM) without rapeseed meal addition, while the experimental group was fed with diet containing different amount of rapeseed meal (A1 = 5.0; A2 = 7.0 and CDP = 12.43%) during different stages of the fattening period. The addition of rapeseed meal to the diet significantly decreased the following parameters: loin colour - lightness L* (control group = 56.26 vs. experimental group = 51.58; P = 0.001), yellowness b* (control group = 10.62 vs. experimental group = 8.90; P = 0.003) and backfat tenderness (control group = 68.53 N vs. experimental group = 51.26 N; P = 0.015). In addition, rapeseed meal in the diet significantly increased the values of pH in ham (control group = 6.35 vs. experimental group = 6.55; P = 0.008). There were no other significant effects of the rapeseed meal addition observed. Along with this finding it can be concluded that rapeseed meal can be used in feeding mixtures for pigs without having any negative effects on the physical parameters of pork meat and fat quality.

Young pigs fixation milk teats, which prevent against other siblings. Heavier piglets are more powerful and easier to get in front of the teats sucking, which are richer on milk. The relationship between fixation front and rear teats, sex and subsequent production of valuable meat parts is not sufficiently understood. The aim of the experiment was to investigate the pig meat production carcase with a focus on valuable and the meaty parts (neck of pork, pork shoulder, ham, chops) in relation to gender and fixation teats after birth. Experiment included 4 sows were Large White breed. After their farrowing litter was monitored. In the experiment were included barrows 15 and 16 gilts. Fixation teats piglets were observed from birth to 72 hours after birth at hourly intervals. After reaching slaughter weight of 105 kg pigs were killed. Carcass dissection was done after 24 hours post-mortem. Evaluated the average weight neck of pork, pork shoulder, ham and chops in > and + who occupied front or rear teats.

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As electron microscopy can reveal much smaller changes in plasma membrane integrity than optical methods, it appears to be a useful tool for evaluating semen quality or the damage inflicted on spermatozoa during preservation. By evaluating membrane integrity of the sperm head in 16 boars by transmission electron microscopy (TEM), it was found that the plasma membrane is very sensitive and tends to break in the acrosomal area but not in the rest of the sperm head. The earliest signs of injury to spermatozoa in the acrosomal part of the sperm head were observed in the plasma membrane that became swollen, broken or lost. The next damaged part of spermatozoa which is less sensitive than the plasma membrane is the acrosome and its external membrane. The freezing process caused a substantial increase in the degree of cell damage manifested as disturbed or missing plasma membrane, acrosomal reaction-like changes and unevenly distributed or lost acrosomal contents. The latter was not found in fresh semen. Using an appropriate buffer concentration for the fixatives applied during preparation of semen samples for TEM appeared as a very important factor due to the impact of their osmolality on plasma membrane integrity of sperm cells.

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The pig is born with low body energy stores and devoid of serum immunoglobulins. Colostrum provides the piglet with both energy and maternal antibodies but its fat and protein composition is very variable. The composition and quantity of colostrum and milk produced by sows is an important factor in successful piglet production. The aim of this study was to determine the changes in the concentration of the nutrients of colostrum of sows during parturition. The concentrations of dry matter, crude protein, fat and lactose of sow colostrum was determined in 20 sows (Large White with various lactation numbers and various litter sizes) at 7 time points throughout first 11 hours from beginning of farrowing. Colostrum nutrients were analyzed with MilkoScan FT 120, Foss A/S. During the first 11 hours from beginning of farrowing increased the concentration of fat by 57.15% and concentration of lactose by 0.28%. At the same time decreased the concentration of crude protein by 28.76% and the concentration of dry matter by 11.78%. We found the impact of sampling time on the concentration of crude protein (P<0,0001). For the fat, lactose and dry matter concentration was the effect non significant.

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The aim of the study was to assess the effects of growth intensity and carcass part on the quantitative and qualitative parameters of muscle fibers. The monitoring was carried out on 72 pigs of balanced sex of the (HxPN) x (LWDxL) genotype. The selected fattening indicators were monitored during the test. Following the slaughter, individual samples of muscle tissue were removed. The samples were obtained from the MLLT (m. longissimus lumborum et thoracis) and MS (m. semimembranosus) of all the pigs. Then, with the use of laboratory equipment, the muscle fibers parameters (numbers and areas) were determined. These were then divided according to their values into three separate groups (intervals) - the group with the lowest, middle and highest parameter values of muscle fibers. It has been demonstrated that for the carcass parts of ham and loin, in the terms of muscle fibers characteristic and monitored growth intensity, the animals with lowest values of muscle fiber qualitative parameters (area) showed the lowest average daily gain and the lowest daily feed consumption. In terms of the feed conversion no general trend was demonstrated. Concerning the number of muscle fibers there was no significant trend found in relation to the monitored fattening performance indicators.

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The study deals with the influence of external environmental factors on pig production. It is safe to assume that with common management and corresponding quality of buildings, technology and other inputs, the microclimate is an important factor in breeding efficiency and health in pigs. Correct parameter setting of the living environment of stables, based on the temperature curves and relative humidity (RH), causes temperature-humidity animal welfare, which significantly affects the production yield. It has been shown that controlled stable microclimate, according to the temperature and RH, significantly increases the live weight (P?0.05) in growers, as well as their growth intensity (P ? 0.01). It was also demonstrated that the selected production traits in pigs of both sections (with controlled and uncontrolled microclimate) are influenced by the current season.

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The objective of this study was to use the data obtained during the process of pig carcass grading to develop prediction equations for the prediction of pig belly composition. Pig carcasses were selected from the population of pigs commercially fattened in the Czech Republic and slaughtered under standard abattoir conditions. A total of 390 carcasses of pigs equally represented by gilts and barrows were used. Within the grading process, lean meat content (x1), cold carcass weight (x2), fat and skin thickness in the P2 point (x3), and muscle thickness in the P2 point (x4) were determined. Twenty-four h post mortem, belly joints were dissected and the proportions of different tissues were determined. Particular emphasis was placed on the content of lean meat as well as intermuscular and subcutaneous fat proportions. The average carcass lean meat content and cold carcass weight were 56.86±0.211 % and 90.21±0.551 kg, respectively. The average lean meat content in the belly was 54.37±0.297 %. The following equation was derived to estimate the belly lean meat content (y): y = -17.49519 + 1.27842 x1 – 0.00912 x2 with the accuracy parameters r = 0.92 and se = 2.38. Prediction equations for intermuscular and subcutaneous fat proportions were also developed. Furthermore, similar equations were derived separately for different genders. A higher accuracy of estimates was detected for gilts.

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The aim of the study was to evaluate the effect of the linseed addition in fattening pigs on the backfat composition, respectively fatty acid profile. The test included 40 hybrid pigs of the LWSx(LWDxL) genotype. Their average age from the birth was 69 days and average live weihgt 28.7 kg. During testing pigs were fed adlibitum by complete feed mixtures. Based on its composition, the animals were divided into two groups. The control group was without linseed, experimental group contained its addition of 15%. The test was finished at an average live weight of 110 kg. After slaughter, the representative samples of the back fat were taken from the right carcass halves (over the last thoracic vertebra), homogenized and subjected to chemical analysis. The results show that linseed addition in the diet changes the fatty acids profile in the backfat in pigs. Also it was shown, the effect of this addition on the n-6 and n-3 PUFA profile in this tissue.

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An analysis of genetic structure in three breeds of small pigs populations in the Czech Republic was a part of a project “The molecular genetic as a tool for effective work in a small populations of pigs.” The panel of 10 microsatellite markers was used for the genetic structure analysis of 509 individuals. Two commercial breeds Pietrain (Pn = 152), Duroc (D = 256) and one native breed (a genetic resource) – Přeštice Black Pied (Pc = 101) were assessed in GenAlEx, STRUCTURE and Microsatellite Toolkit software. The observed heterozygosity for Pn, D and Pc was 0.60, 0.55, and 0.72 respectively. The total number of alleles found for the 10 microsatellite markers was 87 in Pn, 75 in D a 74 in Pc. The analysis of population structure indicates there is very little admixture among breeds. The more distanced breed was Duroc. The results of study confirm that Pc breed as a genetic resource represent interesting reservoir of allelic diversity.

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Four-trait animal models were used to estimate genetic parameters for lean meat percentage, average daily gain from birth to the end of the test, number of piglets born alive in the first litter and number of piglets born alive in the second and subsequent litters for Czech Large White and Czech Landrace pigs. The models differed by considering herd-year-season as random or fixed and by the presence or absence of genetic group effects. Similar heritabilities and genetic correlations between traits were estimated for all four variants of models giving no reason for preferring one of these variants. However, results from the literature show that treating herd-year-season as fixed effect in the genetic evaluation should be desirable because qualitative genetic material has been more and more concentrated in certain herds. The use of genetic groups in the models seems to be problematic and is probably not really necessary.

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Into the observation were included 460 final hybrids of pig carcasses. The sample of carcasses was evaluated on the base of the current valid Czech price-mask. The observation focused closely on the sex, carcass weight and the lean meat content and its effect on the cash sales in selected categories. The fattening of gilts is more effective then by barrows. The difference makes 1.64 CZK on one kg of the carcass. The best price evaluation reached the weight categories from 80.0 to 89.9 kg and from 90.0 to 99.9 kg (cash sales 43.02 and 42.8 CZK/kg of carcass). Best evaluated SEUROP grades were the E (55.0 – 59.9%) and the S class (more than 60.0%) where the cash sales reached 43.5 respectively 43.6 CZK/kg of carcass).

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The purpose of this study was to investigate the presence of immunoglobulins (IgG, IgA, IgM) in the small intestine of piglets during the first 12 hours of postnatal life. A total of 20 crossbred Large White x Landrace sows (180-250 kg body weight) were used, 10 sows with confirmed infection of PRRS virus (Experimental Group) and 10 healthy, PRRS-negative sows (Control Group). Three piglets from each sow were tested at defined time intervals: 3, 6 and 12 hours after the first colostrum intake. Individual intestinal section of duodenum and jejunum were taken at specified intervals and the tissue was subjected to histological and immunohistochemical evaluation. Immunoglobulins were detected by using the primary pig antibodies (Bethyl Laboratories, Montgomery, USA). The colostrum samples from all sows were collected 3, 6 and 12 hours after the onset of labour. The content of the immunoglobulins in the skimmed colostrum was determined by the ELISA method (Bethyl Laboratories, Inc). Subsequently, the comparison between the content of immunoglobulins in colostrum of sows and the presence of immunoglobulins in the small intestine of piglets was performed. The presence of immunoglobulins was significantly higher in the control group, IgM (P<0.05), IgG and IgA (P<0.01), with IgG predominance. The highest mean values of IgG were observed in duodenum and jejunum in interval from 3 to 6 hours after the first colostrum intake. The content of immunoglobulins in colostrum significantly influenced the presence of immunoglobulins in the small intestine of neonatal piglets.

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Agricultural enterprises specializing in breeding pigs in the Czech Republic are characterized by relatively low profitability compared with other types of farming. Nevertheless, the economic results vary depending on production efficiency of pig breeding. The question is how much considerable are the differences. Thus, the aim of the paper is to evaluate differences of economic outcomes in pig breeding, depending on the production efficiency of sows and fattening pigs. The analysis is based on the sample survey of production costs and revenues which has been carried out annually by Institute of Agricultural Economics and Information. The results indicate that mean profitability of pig farming is negative in all intervals of production efficiency, but a smaller loss is realized in case of higher performance of fattening pigs and sows. The cost of a slaughter pigs are highly dependent on the work productivity in breeding sows (number of weaned piglets and their health) as well as on the production efficiency in rearing pigs – these factors affect approximately 50 % of total cost of the slaughter pigs. The remaining 50% is on the stage of fattening pigs.

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The study deals with the influence of different extracted rapeseed meal (ERM) levels in the diet of pigs on the share of individual muscle fiber types and their characteristics in pork. The experiment included the standard test from 22 to115 kg live weight. The animals were divided into 3 study groups according to the amount of extracted rapeseed meal (EMR) in their diet. All the animals were fed ad libitum with the use of complete feeding mixtures (CFM) according to the nutrient standards. The feeding process consisted of 3 phases (22-35, 36-65, 66-115kg) with a continuous transition according to body weight. The first, second and third group of pigs were fed with respect to their body weight phase by CFM containing 3-5-8.1, 5-12-17 and 4-8-14% of ERM. For monitoring quantitative (number) and qualitative (area, diameter) parameters of the muscle fibers the samples from the musculus longissimus lumborum et thoracis (MLLT) were taken. From the final obtained results it is obvious that the animals fed with feed mixture with the highest proportion of ERM had significantly the smallest area (2291.75 mm2) of slow oxidative muscle fibre type I (P < 0.01). Furthermore, these animals, compared to others, had significantly (P < 0.001) a higher proportion of the muscle fibre types I (15.99%) as well as the frequency per 1 mm2 (31.01pc). The results confirm that different content of the ERM in the pig diet can affect the characteristics of the muscle fibers.

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Pigs are one of the main species of livestock bred on Polish agricultural farms. The population of pigs at the end of March 2012 amounted to 11,478, and in comparison with the same period in the previous year it was reduced by 12.4%. For the last six years, there has been a decrease in the pig population, which occurred in all technological groups of a herd. The population of piglets, weaners, fatteners, and pigs kept for raising has decreased too (including sows). Pig population forecasts for the end of 2012 show further decrease by 9.2% (data according to the Foundation of Assistance Programmes for Agriculture).

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Muscle fiber characteristics can vary considerably in different muscle types depending on their function. There are many factors influencing the muscle fiber characteristics, such as the age, breed, hormones, sex, etc. The aim of this study is to assess the effects of slaughter weight and sex on the muscle fibers characteristics in pigs. The study included a total amount of 216 pigs. After their slaughter the slaughter weight, lean meat share and the following muscle fibers characteristics were determined: the area, diameter, perimeter and circularity. All animals were divided into 3 groups (W1, W2, W3) according to their slaughter weight. The groups were characterised based on the carcass weight as W1 = 75.0kg, W2 = 87.4kg and W3 = 99.4 kg. The observed lean meat share was higher in the gilts than in the barrows and this difference increased with increasing carcass weight. Regarding the muscle fiber characteristics, in both barrows and gilts the monitored parameters (area, diameter, perimeter, circularity) increased with increasing carcass weight. Concerning lower slaughter weights the monitored fiber area and diameter were higher in barrows. With increased carcass weight there was a significant difference in the area and diameter parameters between gilts and barrows, with gilts reaching higher values. Generally speaking the higher the lean meat share in animals, the higher the expected muscle fiber areas.

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The aim of this study was to analyze the reproduction performance achieved in sows of CLW breed and hybrid sows of CLWxCL and influencing factors, i.e. age at first mating, gestation length, weaning-to-first service interval and farrowing interval. As a result of the appearance of heterosis effect, 0.34 of average live born piglets more was born in the cross breeds of F1 generation CLWxCL than to the sows of the CLW breed (CLW – 11.00 ? 0.13; CL – 11.34 ? 0.07). The highest number of live-born piglets was demonstrated from 3rd to 5th parity. The effect of age at first mating on the number of average live born piglets was positively reflected in the interval age 256-270 days (10.53 ± 0,39) and 210-225 days (10.47 ± 0,37). The sows with the gestation length up to 114 days (11.34 ± 0.07) delivered by 0.62 live born piglets more than sows with the length of pregnancy over 115 days (10.72 ± 0.16). The mating of the sows up to the fifth day after the piglet weaning had a positive effect on the number of average live born piglets. The sows with farrowing interval up to 162 days had a higher number of average live born piglets (11.54 ± 0.08) than the sows with farrowing interval over 163 days (11.39 ± 0.22).

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The aim of this study was to determine the interactions between gene CAST (MspI, Hinf, RsaI) and gene RYR1 and indicators characterizing the quantitative and qualitative aspects of carcass value in pigs. The study showed a significant interaction between three polymorphisms CAST/HinfI, MspI, RsaI and RYR1 gene in relation to proportion of lean meat as well as the weight of ham (P ? 0.01) and main meat parts (P?0.05). Regarding the fatness of pigs, a clear interaction between CAST/RsaI polymorphism and the amount of fat covering the loin was discovered. Also for all observed polymorphisms (HinfI, RsaI P?0,05; MspI P?0,01) and RYR1 there were significant interactions regarding the amount of fat covering the shoulder. Another important discovered effect was that of the CAST/MspI (P?0.05) and RYR1 gene on intramuscular fat in the neck areas. The study showed significant interactions (P?0.01) between CAST gene polymorphisms HinfI, MspI, RsaI, as well as interactions between the RYR1 gene and meat quality traits (as pH45 MLLT was shown). Another important observation concerned CAST/HinfI polymorphism and drip loss.

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The objective of the experiment was to investigate the effect of natural substances as the potential substitute for antibiotics in the boar extender on sperm survival time. Thirteen natural substances were tested. Natural substances were dissolved in 4% DMSO whit a minimum bactericidal effective concentration of between 300 and 4,800 µg/ml. The control sample was diluted with a semen dilution ratio of 1:1 in an APS extender without antibiotics. The sperm survival was assessed according to sperm motility. Sperm motility was evaluated at 0h, 1h and 24h after semen dilution. The sperm motility was significantly decreased over the storage time for all tested natural substances (p < 0.01). The sperm motility after a 24h storage period was only recorded in hydroquinone monomethylether 10 % and Foeniculi aetheroleum 5 %. The results of the present study indicate a negative effect of the concentrations of natural substances added to semen extender on the boar semen survival time. At present, practical utilization of the natural substances we tested as a potential substitute for antibiotics in boar extenders is not possible owing to its reduced sperm motility.

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The aim of this study was to evaluate the effect of replacing soybean meal with rapeseed meal on the carcass characteristics in pigs and chemical composition of pork meat. 72 hybrid pigs of genotype (DanBred)x(LWDxL) were divided according to their diet into 2 groups. Animals in the control group were fed with a feed mixture containing soybean meal (17.7 - 14 - 9.5%), while the animals in the experimental group were fed with a diet containing rapeseed meal (5 - 7 - 12.43%). In both groups, the feed intake was ad-libitum at all fattening stages. The substitution of rapeseed meal in diet significantly decreased feed intake (2.78 vs. 2.56 kg/d, P = 0.001) and feed conversion ratio (2.57 vs. 2.43 kg/kg, P = 0.028) as opposed to the feed intake observed in the control group. Rapeseed meal in the diet significantly increased water content in the ham (71.56 vs. 72.53%, P = 0.045), decreased crude protein content in the loin (23.18 vs. 22.49%, P = 0.003) and ash content in the ham (1.40 vs. 1.28%, P = 0.005). It can be concluded that rapeseed meal can be used as a direct replacement for soybean meal with no associated growth retardation or decrease in carcass characteristics and meat quality.

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The objective of this study was to evaluate the methods of full and simplified carcass dissections used for the prediction of pig carcass lean meat contents in the Czech Republic. A total of 40 commercially fattened pigs (20 gilts and 20 barrows) were included in the experiment. Carcass dissections were performed 24 h post mortem. Three different methods were used to estimate carcass lean meat contents and the differences between the methods were analysed. The average weight of left half-carcasses was 44.39 kg. The lean meat contents determined by full detailed dissections (I), simplified dissections (II) and using a new reference method (III) were 56.25, 56.46 and 59.02 %, respectively. The difference between the methods I and II was small and statistically insignificant. However, the average lean meat content determined by the method III differed from those determined by the methods I and II by 2.77 and 2.56 percentage points, respectively. This increased estimate of the lean meat content using the method III is related to a new prediction equation introduced by the European Commission in 2008.

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The aim of the study was to evaluate influences with an effect on measured levels of pH1 in pork and to determine occurrence of PSE meat in carcass pigs (n = 277) of tested hybrid combination (CLW x CL) x (D x BL). An influence of sex, used boars, slaughter weight and lean meat percentage in carcass body on measured values of pH1 was studied in this experiment. An average value of pH1 on a level of 6.31 was measured in tested carcass pigs of hybrid combination (CLW x CL) x (D x BL). There were not found statistical conclusive differences between sexes. Higher average value pH1 6.33 was determined in gilts compared to hogs (6.29). Defect of pork meat PSE was found in 7.22 % of slaughter pigs only. A little bit higher number of slaughter animals with PSE defect (12 animals) was found in hogs in comparison with gilt (8 animals). There was not statistical conclusive difference between sexes. With growing slaughter weight the values of pH1 were decreasing. An average value of pH1 on a level of 6.43 was found in slaughter pigs slaughtered in weight of 80 kg or less, pigs slaughtered in 130 kg and more reached value pH1 on a level of 6.19. With growing lean meat percentage in carcass body values of pH1 were growing. The lowest average value 6.13 was determined in pigs with 49.9 – 45.0 of lean meat percentage. On the contrary the highest value of pH1 6.44 was determined in pigs with 60 and higher lean meat percentage. Statistical conclusive differences among values of pH1 were found among different business classes according to lean meat percentage.

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The aim of this study was to verify the effects of adding the organic selenium to the pigs ration (during different fattening periods) on the selected parameters of the fattening capacity and quantitative and qualitative aspects of the carcass value in 72 hybrid pigs. The animals were divided into 4 groups, 3 experimental (where selenium was administered at different times of the fattening period) and one control group (without the addition of selenium). The process of increasing the selenium amount in pork was done by addition of Sel-Plex at a dose of 1mg of selenium/1kg of complete feed mixture. After reaching average live weight of 109.8 kg, the individuals were slaughtered and subjected to detailed dissection. Regarding the evaluation of selected fattening capacity parameters, none of the groups showed any impact of the added selenium. Similar results were obtained for quantitative parameters of the carcass value. In assessing the qualitative indicators of the carcass value, it is obvious that experimental animals, compared to the control group, had better color and higher water content.

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The aim of this study was to demonstrate the significance of year, season, parity and sire-line effects on the reproductive performance in the breeding herd of LWS sows. For this purpose the total of 1 369 sows was monitored during the course of 10 years. All purebred LWS sows were inseminated by LWS boars of various lines within the purebred breeding. The following reproduction traits were monitored for each sow: identity, boar-line, number of total, live born and reared piglets per sow/litter, number of stillbirths, dead piglets and percentage of piglets´ losses, parity of sows and farrowing interval. Nutrition was carried out with respect to sows´ reproduction cycle with the use of commercial complete feeding mixtures (CFM) for nursing (KPK) and gravid (KPB) sows. The results (with regards to the individual monitored traits) were evaluated with the use of the ANOVA-program, and all statistical analyses were performed using the GLM procedure of SAS 9.1. (SAS Institute Inc., 2001). Year, season, parity and line were set as fixed effects while their conclusiveness was evaluated with the help of the Tukey test. Based on the analysis of the sows reproductive performance it can be stated that the monitored herd shows an above-average reproductive performance parameters, piglets losses exceeding 20% and a gradual improvement of zo-technical work, as illustrated by the reduction of the insemination index and by the shortening of the farrowing interval. Another discovered results include the fact, that parity significantly (P <0.0001) influenced the total number of born piglets and also the number of dead piglets and their losses. The study also showed that the year and the season do not significantly affect reproduction in pigs.

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The aim of the study was to estimate the effect of piglet birth weight on future growth intensity of pigs. Piglets (n=80) were weighted after birth, at age of 21 days, 28 days, 38 days, 4 weeks before slaughter, 2 weeks before slaughter and at the day of slaughter. For purpose of the study pigs were divided in four groups according their birth weight (less than 1000 g, 1001-1200 g, 1201-1500 g, 1501 g and more) and average daily gain in particular periods was calculated. Low birth weight was associated with decreased survival and lower postnatal growth rates. The pigs with low birth weight grew slower than pigs with higher live weight at birth. The lowest daily gains were found in pigs with the lowest birth weight during their growing and finishing period (P<0.01-0.001). They achieved the average daily gain from birth to slaughter of 546.04 ± 35.44 g in comparison to pigs with the heaviest birth weight (732.04 ± 40.19 g). Pigs with birth weight 1201-1500 g reached the slaughter weight 14 days earlier than lighter pigs. This finding is important from economic point of view.

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According to the Czech legislation, two authorised methods may be applied for grading pig carcasses with the classification apparatus UFOM 300. These methods were used to evaluate the set of pig carcasses (n=844). Measurements on the carcass were performed both before and after evisceration. The differences between obtained characteristics were not significant when the entire set of carcasses was analysed. Similar results were also observed in the most frequent carcass weight category 80 – 100 kg and in quality grade E. The greatest differences in lean meat content were found in the weight category 100 – 120 kg and in quality grade R characterised by the lean meat content ranging from 45 to 49.9 %.