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Mycotoxins are toxic secondary metabolites produced from fungi. They occur in plants and especially on cereals. One category is fusarium gramminarium which forms zearalenon (ZON) and deoxynivalenol (DON). The development of mycotoxins is influenced by several environmental conditions. So benefit agronomic arrangements like crop rotation, weather conditions during growth/ harvest of cereals and the hygiene conditions during harvest/ storage of cereals the growth of fungi (BUCHELI ET AL., 2005 and SCHNURRBUSCH, 2006). For swine production the mycotoxin topic is very problematical. So there are ZON caused disease for piglets (e.g. low birth weight, genital-/rectumprolaps), gilts (e.g. retardation of puberties beginning), sows (e.g. enlargement of uterus, cysts on ovaries), boars and fattened pigs (ROTH ET AL. 1990 and SCHNURRBUSCH, 2006). There are several trails looking to the influence of mycotoxins to pigs (DÄNICKE ET AL., 2005, DÄNICKE ET AL., 2007 and GOYARTS ET AL., 2007). Mostly they had mixtures from DON and ZON in use. So aim of the trail was and is to investigate the action of just one mycotoxin ZON on sows and piglets after a systematically donation.

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The oedema disease and post-weaning diarrhoea in 4-12 weeks old pigs is associated with the colonization of the small intestine by toxigenic Escherichia coli strain with fimbriae F18. The FUT1 (?-1, 2 fucosyltransferase) gene has been determined as a marker gene for Escherichia coli F18 receptor locus. The M307 polymorphism of the FUT1 gene influences susceptibility to adhesion of E. coli F18 to intestinal mucosa and an outbreak of illness. Enterotoxigenic Escherichia coli expressing fimbriae F4 frequently colonizes the intestine of neonatal and weaned pigs. Susceptibility to enterotoxigenic Escherichia coli with fimbriae F4 is determined with the marker gene MUC4 (sialomicin complex). Mucin 4 (MUC4) is a large membrane-bound O-glycoprotein that is abundant on the surface of gastrointestinal epithelial cells; it plays an important role in the lubrication and protection of mucosa (Peng, 2007). Mx1 gene affects the capability of inhibition the proliferation of RNA virus. An 11-bp deletion in Mx1 gene results in the loss of the ability to suppress viral propagation. Follistatin gene, found in pig chromosome 16, is a new genomic marker for reproductive traits in pigs. FS gene is indicative for the heritable traits of litter size, number born alive, number of fully formed fetuses, number of stillborns, number weaned, weaning weight, average daily gain, and feed efficiency in pigs. Polymorphism in the FS gene is related to reproductive and performance traits in pigs. The main objective of this study was to evaluate presence of resistant alleles of FUT1, MUC4 and Mx1 genes in population of pigs in the Czech Republic and characterize new important gene because of its connection with reproductive and performance traits. Information about this new gene was found in Patent US2007/0186298.

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In our 13-day experiment, piglets weaned at the age of 28 days and divided into two groups of six piglets each were used. The piglets were fed ad libitum with a commercial mix for early weaning of piglets, and had unrestricted access to water. For the experimental group (E), a feed mix with Bacillus toyoi spores in the final concentration 1.103 CFU per 1 g of feed mixture was used. A total of 8g Colistin sulphas per 100 kg live weight were administered in 2 daily doses by adding them to the feed in the trough. Piglets in the control group (C) received feed mix with no supplements. During the experiment, weight of piglets was monitored individually and the amount of feed consumed was monitored per group. Digestibility was determined by an analysis of faeces collected in boxes on days 5, 6 and 7 of the experiment, and adjusted according to the content of sand in the faeces and the feed. During the experiment, the incidence and intensity of diarrhoeas and changes in health were monitored in individual piglets. At weaning and on subsequent days, rectal swabs were taken to monitor the incidence of selected bacterial agents of infections and of the probiotic strain B.toyoi. Bacteriological examination was made by selective cultivation. The comparison of parameters monitored in the two groups of piglets clearly shows that experimental piglets received more feed (505g) compared with the control group (346 g), which is a difference of 46.5 %. While the mean weight gain of piglets in the experimental group was 209.2 g/day, it was only 205.4 g/day in the control group. All the parameters of feed mix digestibility determined at the end of the first week of experiment were higher in the controls. The admixture of tyocerin and colistin had the greatest effect on the digestibility of crude fat (C= 56.32 %, E= 47.85 %) and crude fibre (C= 52.58 %, E= 48.24 %), but the differences found are not statistically significant. No case of diarrhoea was reported in any of the piglets from either group during the experiment. It is no surprise that no weight increases in piglets receiving toyocerin and colistin simultaneously with their feed were found in the feeding experiment and that substantially higher feed consumption per kg of weight gain was found instead.

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This article is continuation from the Research of Pig Breeding Nr.1 Natural compounds and structured biological systems in prevention and adjuvant therapy of infectious diseases of pigs and makes review of current knowledge from this topic. Being a review the abstract can not describe content of the article.

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The objective of this study was to find out the differences and relation of morphologically abnormal spermatozoa incidence (MASI) to seminal plasma (SP), testosteron (T), oestradiol – 17 beta (E2), concentration ions (Ca, Mg, Zn, K, Na) and proportion of allele (A, B) prolactin receptor (PRLR) gene. Thirty-eight ejaculates from 38 AI boars were used. The boars were kept under the same housing and feeding conditions. There were no significant differences between boars in semen volume and sperm concentration. Boars were divided into two groups (I and II) according to significant different of MASI, P < 0.01. In the group I were MASI up to 25 % (x = 5.6 %) and the group II were more than 25 % MASI (x = 53.1 %). Statistically significant differences were not found for all measure parameters between boar group I and II (x: T = 0.93 ± 1,04 vs. 0.61 ± 0.54 ng/ml; E2 = 350.9 ± 452.07 vs. 169.8 ± 126.15 pg/ml; Ca = 0.98 ± 0.62 vs. 0.81 ± 0.37 mM/L; Mg = 16.28 ± 7.92 vs. 14.75 ± 8.70 mM/L; Zn = 0.48 ± 0.15 vs. 0.46 ± 0.18 mM/L; K = 10.64 ± 2.76 vs. 11. 40 ± 3.90 mM/L; Na = 96.96 ± 22.67 vs. 94.58 ± 16.21 mM/L), except of different PRLR alleles frequency proportion within the group II (allele A = 34.4 % vs. allele B = 56.6 %, P < 0.05). Concentration of Zn and K ions in SP of total observed boars (n = 38) was negatively related to MASI (Zn: r = -0.34, K: r = -0.34, P < 0.01). The results of this study lead to a conclusion that the differences between boar SP components and frequency of PRLR alleles correlate with MASI variability.

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The objective of this experiment was to find way of essential fatty acid content changing. Thirty cross breed gilts was divided in two groups and fed with control or linseed diet. The fatty acid composition was measured in samples of muscle tissue and in backfat. The statistical significant differences in fatty acid content were found. Linoleic and alpha-linolenic acid content was increased.

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The aim of this work was to obtain utmost high-quality and viable embryos for cryopreservation and transfer. Selected pubertal breeding gilts were used as embryo donors. Gilts were synchronized by feeding of Regumate (active agent: Altrenogest, producer: Hoechst, doses recommended by the producer) for 15 days. Then they were treated with PMSG and HCG. Homospermic doses were used for insemination. Embryos were recovered post mortem from donors aged from 5,5 to 6 days. Various stages of embryos were found. However only embryos in perihatching developmental stages suitable for transfer or cryopreservation were classified as usable. For cryopreservation stages of early and expanded blastocystes were preferred. During two years 526 embryos from 72 gilts have been obtained, 373 of them were usable. It means 5,2 usable embryos per gilt. Total recovery rate was 42.1%.

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During the first period monitoring of sperm survival was done in 46 samples of breeding boar sperm. Sperms were halved and diluted by two diluting agents in the reason of their quality verification. In used diluting agents reached results in conception and fertility of sows were put in context with sperm survival after 3 days from preparation of sperm doses. Unambiguously was acknowledged that sperm doses with decline of survival under 50% of all spermatids or with higher percentage of survival, but with changed character and velocity of movement (slower moving and luminous spermatids) significantly lower fertility of sows (for 2.66 piglet per litter) and conception after the first insemination (for 9.9%). During the second period preservative effect of two of the best diluting agents of boar sperm (in our opinion) which are accessible in the Czech Republic was put to verification. Diluting agent C (APS+) showed better preservative effect when in 2168 of the first inseminations was reached better of conception for 6.43% and better fertility for 0.17 of piglet compared to diluting agent D (diluting agent with bovine serum albumin) with 2209 of the first inseminations.

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Level of immunity introduced by single or multiple intradermal administrations of various concentrations of antigen in vaccination dose was studied in the paper. Intradermally administered vaccine against Actinobacillus pleuropneumoniae developed comparable immunity to vaccines administered intramuscularly. In spite of intramuscularly induced immunity, there is little known about immunity developed after intradermal administration of different concentrations of antigen in vaccination dose. Intradermal commercial vaccine, containing lipopolysacharid, outer membrane protein and toxins was used, diluted and/or concentrated. The challenge infection was used three weeks after revaccination and protection developed after administration of different concentrations was evaluated and compared to intramuscular administration. Intradermal route was found as comparable to intramuscular administration in protection of lungs against infection, three-time diluted dose was found unless equally effective as standard i.d. or i.m. dose, comparable to 4 times concentrated and 9 times diluted i.d. vaccine.

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The aim of the study was to estimate the effect of packaging forms (0,5 ml midi and 5 ml maxi straws) and two freezing methods of boar semen on reproductive performance of sows and gilts. The study was carried out on 150 crossbreed females (75 multiparous sows and 75 pubertal gilts) and 4 boars. Females have been randomly divided into ten research groups: fifteen pigs in each group. The sows and gilts in experimental groups were inseminated with frozen whilst in the control groups with liquid semen. Each ejaculate was divided into two samples after collection. First sample was frozen according to the method A, whilst second part was frozen according to the method B. Semen was packaged in 0,5 and 5 ml straws and frozen at uncontrolled rate in liquid nitrogen vapours in polystyrene boxes. The females were post cervically inseminated, before AI at every insemination dose 5 mg of PGF2? was added. The occurring of ovulation and pregnancy diagnosis were performed through ultrasonography. In sows inseminated with semen frozen according to the method A and B in 0,5 and 5 ml straws farrowing rate was 80 and 67% vs. 80 and 67%, whilst total litter size was: 10,1 and 9,1 vs. 10,2 and 9,2 respectively. In gilts inseminated with frozen semen according to the method A and B in 0,5 and 5 ml straws farrowing rate was: 73 and 67% vs. 67 and 60%, whilst total litter size was: 9,1 and 8,3 (P?0,01) vs. 8,8 and 7,3 (P?0,01), respectively. In sows and gilts inseminated with liquid semen farrowing rate and total litter size was: 93 and 93%, 12,6 and 10,7 (P?0,01), respectively. Reproductive performance in females inseminated with semen frozen according to the method A were not significantly higher than in pigs inseminated with semen frozen according to the method B, except total litter size in gilts inseminated with semen packed maxi straws (8,3 vs. 7,3) (P?0,01) where the difference was statistically significant. Comparing effect of midi and maxi straws there was no significantly influence of packaging form on reproductive performance of sows, whilst in gilts, females inseminated with semen packaged in 0,5 ml straws, gave significantly higher total litter size than gilts inseminated with semen confectioned in 5 ml maxi straws and frozen according to the method A and B (9,08 vs. 8,3 and 8,8 vs. 7,3) (P?0,01).

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The piglets were fed 4 weeks the commercial feed mixture and those of the experimental group received egg yolk antibodies at 3 g per animal per day from day 1 to day 7. The monitoring of performance was completed by investigation of effects on the digestibility of crude protein (CP), crude fibre (CF), crude fat (F) and ash and bacteriological examination demonstrated haemolytic E. coli. Higher weight gains (C = 342 g/d, E = 427 g/d) were in the experimental group. More effective digestibility were observed in the experimental piglets during the period of supplementation (CP: C = 72.31, E = 76.09 %, CF: C =52.58, E = 55.01%, F: C = 56.32, E = 57.58 %) but, also in the subsequent period (CP: C = 76.41, E = 77.77 %, CF: C = 43.68, E = 55.30 %, F : C = 51.93, E = 57.50 %) when all piglets were feed identical diets. Haemolytic E. coli were negative in the experimental group at post weaning day 5 already.

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An increasing rate of artificial insemination leads to declining number of breading boars (sires) and often to number of genealogical lines. Thereby sires leave more female offspring at herds and the genetic similarity (degree of homozygosity) expressed by coefficient of relationship (Rxy) among dams is increasing. A simplified method based on number of sire lines, sires of dams, and dams within sires, where sows are granddaughters, half-sibs, and sibs, respectively, was used for estimating Rxy in sows of Přeštice breed between 1995 and 2005. The average values of Rxy ranged from 2 to 3% during the observed period, which is favourable for small population of Přeštice breed.

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The present study was conducted to provide data on the seasonal effect on semen production parameters in the fertile hybrid AI boars 24 – 48 months old (n = 1170 ejaculates) in a period of 5 years. The boars were kept in the same housing, feeding and breeding conditions. The semen gel free volume and sperm concentration were determined immediately after the collection. The daily output of spermatozoa was calculated from the total number of spermatozoa per ejaculate and the length of sexual rest. The ejaculates were divided into four groups according to season period of the year: winter (1st – 3rd month), spring (4th – 6th month), summer (7th – 9th month) and autumn (10th – 12th month). Semen gel free volume was significantly the highest (P < 0.001) in autumn 355.08 ± 109.95 ml vs. 294.49 ± 94.27 ml in spring and 320.19 ± 86.22 ml in summer. Sperm concentration was significantly the lowest (P < 0.001) in summer and autumn 276.69 ± 102.27x103/mm3 and 278.37 ± 108.04x103/mm3 vs. 354.37 ± 127.63x103/mm3 in winter and 342.53 ± 121.46x103/mm3 in spring. Number of spermatozoa per ejaculate was significantly the lowest in summer 84.37 ± 27.29x109 vs. 101.31 ± 36.10x109 in winter (P < 0.001), 95.60 ± 34.29x109 in spring (P < 0.001) and in autumn 94.05 ± 34.95x109 (P < 0.01). The daily output of spermatozoa was significantly higher (P < 0.05) in autumn 14.84 ± 6.22x109 vs. spring 13.58 ± 4.97x109. The significantly negative effect of the hot climate stress on semen production traits of boars was determined in the Czech Republic climatic conditions.

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Long term activity of excellent individuals in breeding process is very important element which influences profitability of breeding (Fülöp et al., 1994). Risk of culling is one of criteria of longevity (Wolfová, 1997). Risk of culling describes probability with which is sow culled in a given time in comparison with population average. Risk increases with sow age; there is rising probability of young gilts replacement in herd instead of sows after fourth litter. Reproductive failure, locomotion problems and low milkiness (production of milk) are main reasons for sow culling from breeding. Late return to oestrus and low pregnancy rate are the most frequent reasons for culling in primiparous sows (Dourmad et al., 1994).

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This paper evaluates carcass composition and meat quality of selected final hybrids of pigs. The F1 generation crossbreeds (Czech Landrace x Czech Large White) were used in the mother position and the breed Czech Large White-Sire line and/or OL-48 (Czech Large White-Sire line x Pietrain) and HYB (Czech Large White-Sire line x Duroc, resp reciprocal crossing) were used. In 373 pigs we determined: live weight, lean meat proportion and realization percentage; in 20 animals (10 barrows : 10 gilts) of each combination carcass analyses were done and the percentage of valuable lean cuts and ham, eyemuscle area were determined and the meat quality (pH45, pH24, lightness [L*], drip loss, intramuscular fat, texture) was evaluated. The conclusions confirmed a significant influence of genotype and sex on the carcass value. High variability of slaughter weight of pigs supplied to slaughterhouses remains problematic.

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There were 2 x 16 hybrid sows included into the trial. The trial lasted from 2 weeks before farrowing until weaning at 4 weeks after farrowing. Control group was fed with standard feed for lactating sows, experimental one was fed with control feed (same as that of the control group) with 400 g BioPlus 2B/t feed which equals 1.28x106 CFU/g feed. Milk-samples of all sows were collected on the 3rd and 14th day of lactation. Milk-samples were analyzed for cholesterol, total lipids, protein, lactose and total solids. Blood samples for determination of parameters of protein and lipid profile was taken on day 1 and 15 after parturition.The experimental group had higher content of lipids and cholesterol in milk compared with control group on day 3 and also on day 14 of lactation. No significant differences between groups were observed in total solids and lactose concentration in sow’s milk. Level of cholesterol in blood of experimental group increased. As a result, significant higher cholesterol level was found in experimental group compared to control group on day 15 (P=0,038). Similar to cholesterol, total lipids in blood of experimental group was significantly higher in comparison to control group on day 15 (P=0.007). Results of our experiment indicate that the probiotics based on representatives of the genus Bacillus are able to affect the nutrient composition, e.g. total lipids and cholesterol, of sow´s milk and consequently improve performance and average daily gains of suckling piglets.

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The aim of the study was to compare in vitro fertility in boars with high field fertility to select those suitable for embryo production and determine conditions for oocyte fertilization in terms of spermatozoa treatment and time of gamete coincubation. Fresh semen of four AI-boars, A, B, C and D were used for the experiments. Oocytes were matured by standard protocol. They were fertilized by spermatozoa isolated by Percoll gradient and preincubated in modified Tris-buffered medium (mTBM) without or with 1.5 mM caffeine for 30 min. Both the untreated and caffeine treated spermatozoa were coincubated with oocytes for 3h, 3h 45min or 4h 30min. Oocytes were cultured in PZM-3 medium for twelve hours and than fixed, stained with 33258-Hoechst and examined by epifluorescence. The penetration rates were higher for the untreated spermatozoa of boars A and B compared with those of boars C and D (74.1 ± 11.2 and 77.3 ± 2.8% vs. 12.1 ± 2.8 and 19.7 ± 0.9%). The penetration rate increased from 19.7 ± 0.9 to 74.4 ± 11.4% in spermatozoa of boar D after the caffeine treatment but not in boar C. The normal fertilization rates for untreated spermatozoa of boars A and B were higher than those of boars C and D (25.9 ± 4.2% and 20.6 ± 5.2 vs. 3.0 ± 0.3 and 6.1 ± 0.2%). They increased to 28.8 ± 4.6% in boar B but decreased to 15.4 ± 1.5% in boar A after the spermatozoa treatment; no response was found in boars C and D. In order to improve the course of fertilization process, gamete coincubation time was modified for IVF-suitable boars. The 4h and 30min-coincubation of oocytes with either untreated or caffeine treated spermatozoa was more effective in boars A and B respectively compared with 3h-coincubation interval. It can be concluded that a) It is important to test in vitro fertility of AI-boars before their employment for embryo production b) There is variability in response of boar spermatozoa to caffeine treatment during fertilization c) Independently on the spermatozoa response, the efficiency of fertilization is influenced by time of gamete coincubation.

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Plant secondary products, especially essential oils and tannins, are nowadays good choice for alternative using as animal production improving instead of banned antibiotics. Lemon myrtle, tea-tree and thyme essential oil as well as grape seeds and mimosa tannins were tested to eliminate activity and growth of Clostridium perfringens strain 100. This pathogen causing necrotic enteritis was chosen as representative of microorganism eliminated by antibiotic in last years. All of used additives have eliminated the growth of C. p. culture during the in vitro experiment. The absolute elimination was ensured by approx. 0.1% concentration of tannins or by 0.01 – 0.03% concentration of essential oils.

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Plant secondary products, especially essential oils and tannins, are nowadays good choice for alternative using as animal production improving instead of banned antibiotics. Lemon myrtle, tea-tree and thyme essential oil as well as grape seeds and mimosa tannins were tested to eliminate activity and growth of Clostridium perfringens strain 100. This pathogen causing necrotic enteritis was chosen as representative of microorganism eliminated by antibiotic in last years. All of used additives have eliminated the growth of C. p. culture during the in vitro experiment. The absolute elimination was ensured by approx. 0.1% concentration of tannins or by 0.01 – 0.03% concentration of essential oils.

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Microorganims contaminating boar semen are one of the most important factors that negatively affect the biological quality of spermatozoa. Pseudomonas aeruginosa, Escherichia coli, Proteus sp., staphylococci and enterococci belong to the most frequently isolated bacterial species. Their strong biochemical activity leads to the decrease in energetic sources of seminal plasma and production of metabolites toxic to reproductive cells. Various antimicrobial agents are used to suppress the growth of microorganisms in boar ejaculates. However, long-term use of these drugs causes bacterial resistance, which is a growing health problem in general. The aim of our study was to determine antibacterial activity of various natural substances against microorganisms contaminating boar raw ejaculates.

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Pure pig breed used in hybridization in the Czech Republic was tested in our experiment - together 16 animals of Czech Large White – sire line. These traits were evaluated: an average of back fat thickness, a percentage of main meaty parts, a MLLT area, pH1, pH24 and a content of intramuscular fat. The average height of back fat thickness was determined on a level 18.0 mm, the average percentage of main meaty parts was 53.81 %, an area of MLLT reached 4961 mm2 in average, an average value of pH1 was determined on a level 6.08 and pH24 on a level 5.80. An average percentage of intramuscular fat content was determined on a level 0.62 %. Statistically conclusive higher (p ? 0.05) values in a content of intramuscular fat were reached by hogs (0.75 %) in comparison with gilts (0.52 %).

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The objective of this work was to verify an effect of slaughter weight on basic chemical composition of major pork meat parts. 120 slaughter pigs of a final hybrid combination commonly used in the Czech Republic were used in the test. Pigs were sorted in 4 groups according to their live weight. Representative muscle samples were taken from the right halves of these pigs, which were homogenized and submitted for chemical analysis. In the frame of consideration of the relation between the weight groups of all controlled parameters, then statistically significant differences have been found (P?0.05, 0.01 resp.0.001) at the water content, IMF, as well as the crude proteins and ash matters.

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Presently, when it is not allowed to use antibiotic growth stimulators, the production of pigs has to search for new strategies, especially in the prevention of infectious diseases. The application of natural substances and some microorganisms seems to be a feasible alternative. As these agents do not reach the potency of chemical drugs that have commonly been used previously, it is necessary to develop complex regimes combining various agents with sequential biological effects (adaptogens, antioxidants and scavengers of free radicals and other reactive species (RNOS), anti-inflammatory agents, immunomodulators, antimicrobial substances and synbiotics). Combinations of some substances from the above mentioned classes often exhibit synergistic effects. It makes it possible to reduce doses in complementary mixtures and thus limit the risks of negative influence onfeed and food chain. Using natural products as anti-invasive agents is advantageous due to the fact that they rarely induce resistance. Based on the reported data it can be concluded: The research of antimicrobial agents applicable for nontherapeutic purposes has been intensive, but only approx. 10% of the reported agents (summary standardized extracts, fractions or pure substances) are suitable for practical usage. Pharmaceutical microbiology intensifies the research of suitable bacteria (Lactobacillus, Enterococcus etc.) in view of producing peptides capable to physiologically substitute classical antibiotics. It seems highly probable that animal proteins of milk and some of their degradation products will play an important role. Plants will serve not only as a source of usable metabolites but also as a material for genetic manipulations (introduction of genes encoding expression of animal peptides into the plant cells). Important antimicrobial effects were observed with monoterpenes alone or in a combination with sesquiterpenes (sesquiterpenic lactones). Using complex volatile oils is better than using pure isolated compounds since the effects of individual components are additive or synergistic, and volatile oils have broader antimicrobial spectra. Synergizing the effects is essential since low-molecular anti-invazive agents (small molecules can not be introduced into the feed chain in therapeutic concentrations. Metabolic differences of individual animal species must be taken in account. Only if possible metabolic processes are considered a natural compound or a mixture can be applied in an optimal dose. The dose must be also optimized in view of utilizing nutrients in the feed. For many natural additives, such as tannins, catechins, procyanidins, anti-nutrition effects have not been proven so far. Nonetheless, this aspect requires further studies. Furthermore, additives and their metabolites should not negatively influence the appearance, taste and flavour of final products.

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Simplified detailed dissections were carried out in two sets of pig carcasses (gilts I, n = 120; barrows II. n = 120). The results were used to establish the regression formulae for the apparatus HGP. The lean meat content in gilts (yp) and barrows (yv) can be predicted using the following formulae: Yp = 60.76553 – 0.78012*S + 0.11894*M ( r = 0.83; se = 2.20); Yv = 59.07731 – 0.75232*S + 0.13500*M ( r = 0.82; se = 2.20) To increase the accuracy of the prediction formulae, carcass weight was included into calculation. The prediction accuracy parameters r and se did not practically change. It is therefore concluded that the inclusion of carcass weight in the prediction formulae does not improve the prediction accuracy.

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Simplified detailed dissections were carried out in two sets of pig carcasses (gilts I, n = 120; barrows II. n = 120). The results were used to establish the regression formulae for the apparatus HGP. The lean meat content in gilts (yp) and barrows (yv) can be predicted using the following formulae: Yp = 60.76553 – 0.78012*S + 0.11894*M ( r = 0.83; se = 2.20); Yv = 59.07731 – 0.75232*S + 0.13500*M ( r = 0.82; se = 2.20) To increase the accuracy of the prediction formulae, carcass weight was included into calculation. The prediction accuracy parameters r and se did not practically change. It is therefore concluded that the inclusion of carcass weight in the prediction formulae does not improve the prediction accuracy.

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The objective of this study was to document the accuracy of the classification equipment used in the Czech Republic with respect to error problems in lean meat percentage prediction like equipment error. For this purpose a total of 360 pigs were measured in abattoir. From the results obtained one could say that various instruments provide identical measurement of fat depth (r = 0.57-0.97), while for muscle depth the performance is worse (r = 0.38-0.78) which causes a fluctuation in the prediction of lean meat percentage with differences ranging from -2.56% to +2.81%.

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The trial was performed in 194 final hybrid pigs of well-balanced sex in commonly used breeding combinations in the Czech Republic. The objective was to examine the belly meat part formation with respect to its total content as well as its formation in the carcass and lean meat share depending on achieved carcass weight. It was demonstrated that increasing weight within the monitored group of pigs does not result in higher belly share in the carcass, whereas the percentage growth of EU-belly as well as total belly part was consistent. The increasing carcass weight results with dramatically lower rising of absolute amount of lean meat in the belly (2,05kg/95kg vs. 2,33kg/115kg) whereas belly lean meat share decreased (55,68%/95kg vs. 52%/115kg). Lean meat share and belly one do not achieve the same values. The higher carcasses the higher difference between them.

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The trial was performed in 194 final hybrid pigs of well-balanced sex in commonly used breeding combinations in the Czech Republic. The objective was to examine the belly meat part formation with respect to its total content as well as its formation in the carcass and lean meat share depending on achieved carcass weight. It was demonstrated that increasing weight within the monitored group of pigs does not result in higher belly share in the carcass, whereas the percentage growth of EU-belly as well as total belly part was consistent. The increasing carcass weight results with dramatically lower rising of absolute amount of lean meat in the belly (2,05kg/95kg vs. 2,33kg/115kg) whereas belly lean meat share decreased (55,68%/95kg vs. 52%/115kg). Lean meat share and belly one do not achieve the same values. The higher carcasses the higher difference between them.

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The aim of this study was verify suitability of selected treatments at gilts oestrus and ovulation induction and synchronization, compare influence of these treatments on selected reproduction traits quality in connection with their usage in embryo- transfer or in practical conditions. Czech Large White and Czech Landrace pubertal gilts (7 month of age, 130-140 kg weight) were used in our experiment. Gilts are synchronized by feeding of Regumate (active agent: Altrenogest, producer: Hoechst, doses recommended by the producer) for 15 days. Then they are treated with PMSG and HCG (Werfachor in first group, Pregnyl in second group) or GnRH (Depherelin Gonavet in third group). Homospermic doses were used for insemination. Achieved results show that the most suitable from used methods for follicle stimulation and development is combination of Regumate-Sergon-Werfachor preparations (eventually substitution with Depherelin Gonavet).

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Organoleptic qualities (odour, flavour, texture and juiciness) of pork from pigs fed with ground linseed were investigated in the experiment. The experiment was carried out from 37 to 98 kg live weight in 4 groups (control group-L0, L1-6,7 % of ground linseed, L2- 13,4 % of ground linseed and L3 -13,4% of linseed and 103 mg of a-tocopherol in the diet) of 10 fattening crossbreed gilts each. The characteristics were evaluated by trained taste panelists and maximum 7 points were assigned to meat samples. There were not differences between the control group and experimental groups. The oxidative stability of muscle lipids was higher in L3 group (a-tocopherol supplementation) compared with other groups.

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Numerous papers in the literature confirm the influence of nutrition on features of reproduction in pigs. Lactation is a very sensitive time in the reproductive cycle. During this period the uterus and ovaries have to regenerate. This process requires about 3 weeks. A few exogenous influences stimulate regeneration of the reproductive organs, others delay the process. A short regeneration period without disturbances promotes short weaning to oestrus intervals. Follicular development is the main prerequisite for ensuring the onset of oestrus in weaned sows. The objective of the experiment was to investigate the natural response at various times after weaning result from different nutrition involving various energy intake levels over a 3 week lactation period.

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