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Modern single space feeding systems for fattening pigs allow the detailed assessment of an individual animal's feeding behaviour. In an experiment involving 96 fattening pigs, the influence of deoxynivalenol (DON) contaminated feed (> 4 500 µg/kg DON) on the zootechnical performance and feeding behaviour was compared with a feed with low DON concentration (< 900 µg/kg DON), this served as the control group. Additionally, in separate treatments, two commercial mycotoxin binders were added to the DON-contaminated feeds to assess if an expected DON effect could be attenuated. The high DON content significantly (P < 0.03) reduced daily feed intake (500-600 g/day). The DON group showed 240 g less daily gain compared to the control with 728 g/day. Both mycotoxin binders were seen to additionally depress weight gain by approximately 65 g/day (P < 0.01). The treatment did not affect the individual feeding behaviour as assessed by daily visits to the feeder, feed intake per visit and the highest feed intake per visit per day. These were influenced only by the pig and its pen, indicating that the animals developed a distinct behaviour within their respective groups. Behaviour analyses of persistency and day-to-day variation showed that the persistency was reduced and variation was increased when DON without or with binder was present. The DON contents therefore seemed to lead to a more erratic and less consistent behaviour that remained dependent on the animal group.

This study was conducted to investigate the effect of Lactobacillus zeae LB2 on the gut microbiota in piglets infected with enterotoxigenic Escherichia coli (ETEC). Thirty-two healthy 7-day-old piglets were randomly divided into four treatment groups: control group (basal diet), LB2 group (supplemented with 1 × 10⁸ CFU/pig/day L. zeae LB2), ETEC group (infected with 1 × 10¹⁰ CFU/pig/day ETEC) and ETEC+LB2 group (LB2 supplementation + ETEC infection). Intestinal contents were collected for DNA extraction and Illumina sequencing. Significant result was observed for alpha diversity in the four intestinal sections, and both ETEC infection and LB2 supplementation showed a higher Chao1 alpha diversity. At the phylum level, Firmicutes and Bacteroidetes were dominant in the healthy piglets, while Proteobacteria were dominant in the ETEC-infected piglets. At the genus level, ETEC infection decreased the abundance of Prevotella, Ruminococcaceae, Lactobacillus, Alloprevotella, Flavobacterium, and Sutterella and increased the abundance of Actinobacillus. The LB2 supplementation reduced the abundance of Ruminococcaceae, Actinobacillus, Porphyromonas, and Alloprevotella, and increased the abundance of Prevotella and Lactobacillus. Both ETEC infection and LB2 supplementation affected several functional pathways associated with cellular processes, environmental information processing, genetic information processing, diseases, metabolism, and organismal systems. In summary, ETEC infection induced dysbiosis of the gut microbiome in piglets, while L. zeae supplementation could positively regulate the gut microbiome during ETEC infection. Therefore, L. zeae LB2 may be an ideal probiotic for the prevention or treatment of ETEC infection.

In this study, the relationships of temperature humidity index (THI) with milk yield and some physiological responses in dairy cattle were investigated. Our goal in the meta-analysis was to find the parameter(s) primarily affected under heat stress. A total of 16 studies with the temperature humidity index value higher than 72, which is an important factor in determining the effect of heat stress, were included in the meta-analysis. The variables of interest in the meta-analysis included: milk yield (kg/day), respiratory rate (breaths/min), rectal temperature (°C). In addition to the meta-analysis, principal component analysis (PCA) was also performed. In the meta-analysis, high variation or heterogeneity (I² > 99%) was determined between the results of the studies. This may depend on many factors (climate, region, number of samples and management etc.). Heterogeneity is desirable in the meta-analysis, because it provides accurate and reliable interpretations of the variances of parameters. Due to high heterogeneity, the results of the studies were combined according to the mixed model. According to the mixed model and PCA results, a linear relationship was determined between the temperature humidity index and these physiological parameters. According to the meta-analysis, at THI > 72, the mean effect size of milk yield was 50%, and the effect sizes of respiratory rate and rectal temperature were approximately 65% and 38%. All three parameters have a significant effect under heat stress (P < 0.000 1). As a result, there is a linear relationship between temperature humidity index, milk yield and physiological parameters. According to the other characteristics, the respiratory rate was determined as the primary response parameter in parallel with the increase in temperature humidity index.

The aim of the current research was to analyze the linear type traits of Hungarian Simmental dual-purpose cows scored in the first lactation using principal component analysis and cluster analysis. Data collected by the Association of Hungarian Simmental Breeders were studied during the work. The filtered database contained the results of 8 868 cows, born after 1997. From the evaluation of main conformation traits, the highest correlations (r = 0.35, P < 0.05) were found between mammary system and feet and legs traits. Within linear type traits, the highest correlation was observed between rump length and rump width (r = 0.81, P < 0.05). Using the principal component analysis, main conformation traits were combined into groups. There were three factors having 84.5 as total variance ratio after varimax rotation. Cluster analysis verified the results of the principal component analysis as most of the trait groups were similar. The strongest relationship was observed between feet and legs and mammary system (main conformation traits) and between rump length and rump width (linear type traits).

The aim of this study was to monitor the Czech Aberdeen Angus population for backfat thickness (BT), musculus longissimus lumborum et thoracis (MUSCLE) and live weight (LW) in relation to environmental and genetic conditions. In this study, we also wanted to display the potential for future inclusion of these parameters into national monitoring. Parameters of BT, MUSCLE and LW were measured at 120, 210, and 365 days of age in 769 Aberdeen Angus calves (417 bulls and 352 heifers) on seven farms. Statistical evaluation was performed in the SAS v9.3 software. The bulls achieved significantly higher (P < 0.01) weights and larger MUSCLE compared to the heifers, although the heifers had higher BT. The age of the dam at calving significantly influenced the growth ability of tested calves, but it did not influence BT nor MUSCLE. The nested effect of the year-season, farm and sire bulls (or genetic background) significantly affected LW, BT and MUSCLE of tested calves. The use of the same breeding bulls on different farms resulted in significant differences in growth parameters. Our results displayed the potential of nationwide monitoring of MUSCLE and BT of beef breeds, as official parameters of the beef performance testing in the Czech Republic. The inclusion of these globally used traits in the Czech breeding system would allow to predict breeding values for the Czech beef population. This would lead not only to general improvement of MUSCLE in the population, but also to the production of better breeding animals and slaughter animals with higher value.

The aim of the present study was to investigate the effect of digestible amino acid (DAA) based formulation strategy, and l-valine (l-Val), l-isoleucine (l-Ile) and l-arginine (l-Arg) supplementation to reduce the crude protein (CP) level of broiler diets on performance, carcass characteristics and protein efficiency ratio by comparing with the control diet formulated on total amino acid base. A total of 792 one-day-old Ross 308 broiler chicks were divided into 48 floor pens, with 24 pens containing 16 chicks and 24 pens containing 17 chicks. The experiment was organized in a completely randomized block design with four dietary treatments as follows; T1: formulated to meet minimum both total amino acid and DAA requirements without using l-Val, l-Ile, and l-Arg, T2: formulated to meet DAA requirements without using l-Val, l-Ile and l-Arg, T3: formulated to meet DAA requirements by using l-Val alone, T4: formulated to meet DAA requirements by using l-Val, l-Arg, and l-Ile. Each treatment had 12 replicates. Neither l-Val (T3) nor l-Val, l-Ile, and l-Arg supplemented (T4) low CP dietary treatments had any negative impact on growth performance, feed conversion ratio during experimental periods, as well as carcass parameters of broilers. Indeed, CP reduction by the addition of l-Val alone or l-Val, l-Ile, and l-Arg together even resulted in a significant improvement in protein efficiency ratio compared to T1 and T2 treatments. Supplementation of l-Val either alone or along with l-Ile and l-Arg to diets formulated based on DAA not only decreased dietary CP but also soybean meal inclusion. It can be concluded that maintained growth performance, and even improved protein utilization can be achieved due to the DAA based formulation strategy and supplementing broiler diets with l-Val alone or together with l-Ile and l-Arg.

The objective of this study was to evaluate the inter-breed genetic diversity of Lithuanian Trakehner horses. The current population in Lithuania numbers 1 039 Trakehner horses. The study included the immunogenetic data analysis of 316 blood samples. Pedigree was traced back to 7-11 generations. The horses were assigned to genealogical clusters originating from East Prussian Trakehner Stud, Thoroughbred and Arab sires. The first two clusters were subdivided into nine-horse groups according to the most important ancestors. The evaluation of genetic diversity was based on six blood groups and five protein polymorphism systems. The differences between genealogical groups were confirmed by principal component analysis and applied cluster analysis. According to the allelic frequency, the Trakehner population changed very slightly through a 30-year period, and only one rare (0.013) allele Tf^RR (frequent in other Trakehner populations), has been newly found. The analysis of genetic polymorphism systems based on a very low rate of alleles Q^abc (0.093) and D^dkl (0.046), which are typical of other populations, indicated the exclusivity of the Trakehner population in Lithuania. The average expected heterozygosity by blood protein polymorphism and blood groups were 0.409 and 0.441, respectively. The genetic clustering diverged by observed heterozygosity of blood groups and by pedigree data in Pilger through Egoist, Bay Ronald through Dark Ronald and Dampfross through Hyperion subgroups. The determined distinctiveness of subdivided Trakehner horse groups suggests reconsidering the breeding strategies and conservation programme of Trakehner horses. Breeding and selection of subdivided sire lines could be among the appropriate solutions for the maintenance and extension of the genealogical structure.

This study compared different methods of determining starch digestibility (in vivo vs in vitro) in wheat grains and evaluated the influence of extrusion on digestibility. In vivo starch digestibility was determined in broiler chickens by calculating the residual starch content in their ilea and the digestibility using a chromium oxide indicator. In vitro digestibility was examined using pepsin and pancreatin. During in vivo testing, the highest digestibility coefficient (DC) was achieved by the Bonanza variety in its extruded form (91.19 ± 0.40%). In contrast, the lowest DC was achieved by the Tobak variety in its non-extruded form (81.45 ± 1.92%). Generally, a higher DC was observed in vivo for extruded forms of wheat. During in vitro testing, the highest DC was achieved by the Stefii variety in its non-extruded form (96.10 ± 0.55%), whereas the lowest DC was observed in the Yetti variety in its extruded form (49.72 ± 0.41%). Overall, the in vitro experiments did not exhibit significant differences between extruded and non-extruded forms of wheat. Linear regression analysis showed a strong relationship (r² = 0.860; 85.98%) between in vivo- and in vitro-derived DC values in all wheat varieties, both in extruded and non-extruded forms. The study showed that in vivo testing is a suitable method for the determination and control of starch levels in extruded materials. However, despite the accuracy of this technique, it is also very demanding in terms of time, space, equipment, and methodological knowledge. Therefore, based on the strong correlation between the in vivo and in vitro assays, we recommend in vitro digestibility testing as a preferable alternative.

The objective of this study was to calculate economic weights for ten current breeding objective traits and for four new traits characterising claw health and feed efficiency in Czech Holstein cattle and to investigate the impact of different selection indices on the genetic responses for these traits. Economic weights were estimated using a bio-economic model, while applying actual (2017) and predicted (2025) production and economic circumstances. For the actual situation, the economic weights of claw disease incidence were -100.1 € per case, and those of daily residual feed intake in cows, breeding heifers, and fattened animals were -79.37, -37.16, and -6.33 €/kg dry matter intake per day, respectively. In the predicted situation, the marginal economic weights for claw disease and feed efficiency traits increased on average by 38% and 20%, respectively. The new traits, claw disease incidence and daily residual feed intake, were gradually added to the 17 current Holstein selection index traits to improve the new traits. Constructing a comprehensive index with 21 traits and applying the general principles of the selection index theory, a favourable annual genetic selection response was obtained for the new traits (-0.008 cases of claw disease incidence and -0.006 kg of daily residual feed intake across all cattle categories), keeping the annual selection response of the most important current breeding objective traits at a satisfactory level (e.g., 73 kg of milk yield per lactation, 0.016% of milk fat). Claw health and feed efficiency should be defined as new breeding objectives and new selection index traits of local dairy population.

The objective of the present study was to estimate the effect of breed on milk fatty acid (FA) composition of dairy (Brown Swiss, Holstein-Friesian, and Jersey) and dual-purpose cows (Simmental and Alpine Grey) in multi-breed herds. Information on individual milk samples was collected during routine cow milk testing between 2011 and 2014, and consisted of 285 606 observations from 17 445 cows in 617 herds. Fixed effects included in the mixed model were breed, parity, stage of lactation and the interaction between parity and stage of lactation, and random effects were cow, herd-test-date and residual. Contrast estimates for the studied traits were used to compare specific sets of breeds. Holstein-Friesian produced more milk than the other cattle breeds, with the greatest trans FA and C18:1 and the lowest C18:0 content. Comparison between the specialised dairy vs the dual-purpose breeds highlighted significant differences for all traits except for polyunsaturated FA and trans FA content. Specialised dairy breeds had greater milk saturated FA, short-chain FA, medium-chain FA, C14:0 and C16:0 content, and dual-purpose breeds produced milk with greater content of monounsaturated FA, long-chain FA, C18:0 and C18:1. Results demonstrated that, although specialised dairy produced more milk than dual-purpose breeds, milk FA profile of the latter was more favourable from a human nutrition point of view.

Aquaculture, as the fastest growing agriculture sector, is currently focused on exploring the development of effective intensive recirculating systems (RAS). The use of intensive RAS requires a stable supply of fingerlings throughout the year. Salmonids are a highly important aquaculture species, with rainbow trout Oncorhynchus mykiss often reared in freshwater RASs. The dominant position of rainbow trout has triggered the investigation of a wider diversification of species, including brook char Salvelinus fontinalis. Brook char has the potential to be reared in facilities similar to those used for rainbow trout, but it is not known if brook char is suitable for hatching in an intensive recirculating hatchery system (RHS) to provide a consistent supply of fingerlings to an associated RAS roughly every three months. The present study evaluated the feasibility of producing brook char fingerlings in an RHS and compared results to those obtained with rainbow trout. A production cycle from eyed egg to fingerling was completed separately for rainbow trout, brook char, and parallel rearing of both species for the comparison of growth rate, feed conversion ratio, and the time to reach individual fingerling weight of 2 g. The results showed slower growth rate of brook char compared to rainbow trout reared under the same conditions and a significantly longer production cycle (~108 days), compared to rainbow trout (~74 days). Results suggest that brook char is not suitable for parallel rearing in facilities with primary rainbow trout production. The main practical problem is disruption of the production cycle which requires fingerling stocking at 3-month intervals.

The objectives of this study were to estimate linkage disequilibrium (LD), describe and scan a haplotype block for the presence of genes that may affect milk production traits in Portuguese Holstein cattle. Totally 526 animals were genotyped using the Illumina BovineSNP50 BeadChip, which contained a total of 52 890 single nucleotide polymorphisms (SNPs). The final set of markers remaining after considering quality control standards consisted of 37 031 SNPs located on 29 autosomes. The LD parameters historical recombinations through allelic association (D') and squared correlation coefficient between locus alleles frequencies ( r²) were estimated and haplotype block analyses were performed using the Haploview software. The averages of D' and r² values were 0.628 and 0.122, respectively. The LD value decreased with increasing physical distance. The D' and r² values decreased respectively from 0.815 and 0.283 at the distance of 0-30 kb to 0.578 and 0.090 at the distance of 401-500 kb. The identified total number of blocks was 969 and consisted of 4259 SNPs that covered 159.06 Mb (6.24% of the total genome) on 29 autosomes. Several genes inside the haplotype blocks were detected; CSN1S2 gene in haplotype block 51 on BTA 6, IL6 and B4GALT1 genes in haplotype blocks 6 and 33 on BTA 8, IL1B and ID2 genes in haplotype blocks 19 and 29 on BTA 11, and DGAT1 gene in haplotype block 1 on BTA 14. The extension of LD using BovineSNP50 BeadChip did not exceed 500 kb and its parameters r² and D' were less than 0.2 and 0.70, respectively, after 70-100 kb. Consequently, the 50K BeadChip would have a poor power in genome wide association studies at distances between adjacent markers lower than 70 kb.

RE-NUM-OR is a new, flexible, and user-friendly renumbering and reordering data arrangement software for unprocessed pedigree files used in genetic evaluation systems for personal computers. RE-NUM-OR was written using Python (Ver. 2.7.13) 64 byte programming language and compiled with PyInstaller-3.2.1 software which is a set of utilities for freezing Python scripts into executable. RE-NUM-OR not only runs on 32 or 64 byte MS Windows but also runs on 64 byte GNU/Linux. The program has new, practical, and simple interface and the user does not need to create a parameter file for running the program and .txt, .xlsx or .et extension files can be used as input files directly. Output files (.txt, .xlsx, .et, .dat) can be obtained. For animal, sire and dam IDs, it can read all standard characters (ASCII codes from 32 to 126) in input files. The program supports both dot (.) and comma (,) for numerical data. Pedigree lines for parents do not need to be arranged prior to their progeny. If pedigree lines for parents follow their progeny, the program can detect this and it can reorder the animals as pedigree lines placing parents prior to their progeny. Another feature of this software is that it has a pop-up window with error notification. Also, it supports repeated observations. RE-NUM-OR executable, its user manual, and sample input files are available from www.kemalyazgan.com.tr.

Lamb growth performance traits in relation to parental breeding values (BVs) for these traits were evaluated in a purebred Suffolk sheep population in the Czech Republic. The research lasted over 8 years and included 24 886 lambs. Four relevant parental BVs were observed: BV predicted for lamb live weight direct effect (BVLW-DE), BV predicted for lamb live weight maternal effect (BVLW-ME), BV predicted for lamb musculus longissimus lumborum et thoracis depth (BV-MLLT), and BV predicted for lamb backfat thickness (BV-BT). The lamb live weight (LW; kg), musculus longissimus lumborum et thoracis depth (MLLT; mm), and backfat thickness (BT; mm) were assessed at 100 days of age. A dataset was created using the most current parental BVs for each year (2007-2014) and subsequent growth traits of their lambs in the next season (2008-2015). Linear regressions showed an increased tendency when one point in dam BVs was associated with an increase in lamb LW (0.393 kg; P < 0.01 in BVLW-DE and 0.090 kg; P < 0.05 in BVLW-ME), MLLT (0.340 mm; P < 0.01 in BV-MLLT), or BT (0.243; P < 0.01 mm in BV-BT). Lower (but significant - P < 0.01) values on linear regression were detected for sire BVs, when 0.135 kg of LW, 0.217 mm of MLLT, and 0.214 mm of BT corresponded to 1-point increases of BVLW-DE, BV-MLLT, or BV-BT. This was confirmed by ANOVA evaluation, especially for LW and MLLT traits. Maximal differences (P < 0.05) in lamb LW were 1.84 kg or 0.88 kg regarding to dam or sire BVLW-DE groups. Similarly, the difference (P < 0.05) in lamb MLLT reached 0.82 mm in dam BV-MLLT, while 0.57 mm was detected in sire BV-MLLT groups. These results have practical implications for the objectives of selection schemes used in the Suffolk sheep population in the Czech Republic.

Egg quality and eggshell ultrastructural properties of four Saudi native chicken breeds were compared to detect genetic differences. A total of 480 laying hens at 28 weeks of age, representing four Saudi native breeds of chicken (black, black-barred, gray, and brown) kept under hot environmental conditions (34 ± 1°C) were randomly assigned to the current experiment. Laying hens were housed in individual cages in an open-sided house during hot summer season. A total of 360 intact eggs were randomly collected (90 from each breed) for egg quality assessment. Eggshell samples were prepared to evaluate ultrastructural measurements using a scanning electron microscope. No significant variations between the breeds concerning egg weight, egg-shape index, yolk index, albumen (%), yolk (%), shell (%), and shell thickness traits were detected. Brown breed showed significantly higher Haugh units compared to the other breeds. Moreover, brown breed scored the best for eggshell breaking strength trait (the highest crack resistance), followed by gray, black, and black-barred breeds, respectively (P < 0.005). Total ultrastructural score for mammillary layer measurements was significantly higher in black-barred breed if compared with black, brown, and gray breeds. Gray, brown, and black Saudi native breeds had an outstanding eggshell ultrastructure and, in turn, stiffer and stronger eggshell comparable with black-barred counterpart under high ambient temperatures. At the national level, for cross-breeding and selection programs aimed at producing good quality table and hatching eggs the use of gray, brown, and black breeds can be recommended due to excellent ultrastructural properties of their eggshell.

This study examined the variability of reproductive and productive traits in Suffolk sheep (a commercial flock, n = 316 ewes) with regard to the dams' age or the nutritional status of sheep at mating under a year-round outdoor management. Data were collected across a 3-year monitoring period (totally 655 observations). The fixed effects of dam's age (dams grouped as: 2, 3, 4, 5, 6 years and older), ewe's live weight (LW; ewes grouped as: < 72 kg; 72-83 kg; > 83 kg), and backfat thickness at mating (BT; ewes grouped as: < 7.9 mm; 7.9-10.5 mm; > 10.5 mm) were evaluated. The dam's age influenced reproductive and productive traits such that 2- and 6-year and older ewes reached the lowest values. Ewes with LW > 83 kg had significantly higher lambing rate (11.8%) compared to those with LW < 72 kg. The group of ewes with LW < 72 kg gave birth to a significantly lower number of live lambs in litter (-8.9%) in comparison with LW < 83 kg group. An increase (9.9%; P < 0.01) of total litter weight at birth or an increase (12.5%; P < 0.05) of total litter weight at 100 days of age were detected in LW > 83 kg group compared to LW < 72 kg group. BT > 10.5 mm ewes had by 8.9% lower lambing rate (P < 0.05), by 6.8% lower litter size (P < 0.05), by 14.5% lower number of live lambs in litter (P < 0.01), and by 8.6% lower total litter weight at birth compared to BT < 7.9 mm ewes. A significantly lower total litter weight at 100 days of age (-10.8%) and a significantly lower total litter gain from birth to 100 days of age (-11.5%) were detected in BT > 10.5 mm ewes in comparison to BT 7.9-10.5 mm ewes.

Human scent is a complex combination of many chemical substances. Skin is supposed to be one of sources of scent traces. The values of the boiling points of human scent compounds were supposed to be lower than 300°C. The purpose of the study was to determine the temperature at which the human scent is degraded so that a dog would not be able to identify it. In contrast to expectations, eight dogs used in the experiment almost flawlessly identified human scents from five scent donors exposed to temperatures of 100°C, 200°C, 300°C, 400°C, 500°C, 600°C, 700°C, and 800°C. Only two of the dogs were able to identify 5 of 15 scent samples exposed to 900°C. No dog identified a scent exposed to 1000°C. Our study verified heat survivability of human scent far beyond existing expectations. There may be an extremely heat resistant, previously undetected, compound of human scent, unsusceptible to heat which exceeds standard temperatures used for sterilization. We anticipate our results to be a starting point for cardinal change of our view of factors affecting the vulnerability of human scent, resulting in the need to alter the approach of forensic methodology dealing with identification of human scent.

In this study, the quality of northern pike eggs collected by the traditional method (hand stripping) and the pneumatic method (air stripping) was compared. Additionally, different activation solutions (Billard solution, hatchery water, and Woynarovich solution) were tested for their effects on egg fertilization under artificial conditions. After the eggs were collected, the Pseudo-Gonado-Somatic Index (PGSI) was measured. Although the values of the PGSI in the samples obtained with use of air stripping were lower (13.8 ± 3.9%), they did not differ statistically from those obtained by hand stripping (16.5 ± 5.4%). Hatchery water and Woynarovich solution were found to be the most suitable solutions for sperm activation using the Computer-Assisted Sperm Analysis (CASA) system as compared to the Billard solution. Hand stripping was found to negatively affect the percentage of fertilized eggs and the percentage of hatched larvae in samples fertilized in hatchery water and Woynarovich solution. When the traditional method of egg collection was used, there were no differences in the percentage of fertilization and the percentage of hatched larvae between Billard solution (54.0 ± 21.5% and 44.1 ± 21.9%, respectively), hatchery water (60.0 ± 22.5% and 55.9 ± 22.8%, respectively), and Woynarovich solution (72.0 ± 25.8% and 69.0 ± 23.9%, respectively) treatments. Air stripped eggs showed a higher fertilization rate when hatchery water or Woynarovich solution was applied (86.2 ± 9.3% and 92.4 ± 3.9%, respectively). Also hatching rate was the highest in these samples (83.0 ± 8.4% and 88.3 ± 6.2%). The application of the pneumatic method and Woynarovich solution to northern pike artificial fertilization resulted in higher fertilization and hatching rates as compared to other techniques. Because this was successful in northern pike, the use of air stripping is a promising option for artificial reproduction in other fish species.

The study aimed at an evaluation of fattening and slaughter performance as well as meat quality of the native Złotnicka Spotted (ZS) pigs and its crosses with Duroc pigs. The experimental material comprised 60 fatteners, divided into three genetic groups of 20 animals (100% ZS, 75% ZS and 50% ZS). The specific character of conservative breeding results in low values of fattening and slaughter performance traits observed in ZS breed. Among the analysed groups, animals with 100% share of ZS genes in their genotype were characterised by low daily weight gains (0.59 kg), considerable backfat thickness (34.96 mm), slight muscle thickness (48.05 mm), and low leanness (41.83%). These parameters were higher in both groups of crosses. Differences between the 100% ZS group and the 50% ZS group were significant for backfat thickness and highly significant for leanness. Acidity and colour parameters analysis showed that meat from all the genetic groups analysed was characterised by a good quality. The highest pH₄₅ values were in the 75% ZS group, and meat from this group had the darkest colour (L* = 49.73) and the highest red colour share (a* = 5.11). Statistical analyses showed that ZS breed retained its original traits through the years of breeding. It was confirmed that meat of Złotnicka Spotted breed is characterised by excellent quality. The results indicate that ZS and Duroc breeds crossing improves fattening and slaughter performance, while maintaining good meat quality in their crosses. Results of this study may also be used by breeders. They indicate that crosses of both the breeds kept in extensive breeding may be successfully used in high quality meat production. Pork from such animals may be a raw material for market niche production, such as regional products. The use of meat from crosses in meat processing may improve both quality of the processed products and efficiency of production based on the native Złotnicka Spotted breed.

Using the tests of methanogenic activity (TMA) changes in methane yield (Y_CH4) and anaerobic degradability (D_c) of organic matter of feeds and excrements were studied in an experimental group of six horses while complete analytical methods were applied (N-compound matters, proteins, non-protein N-compound matters, fat, nitrogen-free extract, ash, crude fibre, organic matter, NDF, ADF, hemicelluloses, cellulose, lignin and chemical oxygen demand COD) and the material balance was determined. The horses utilised 48.8% of organic matter of feeds in dry matter while the daily weight of droppings was 21 kg with 5.20% of dry matter and 4 kg of urine with 7% of organic matters. It is important that the theoretical methane yield per 24 hours corresponding to the organic matter of ingested feeds which was transferred to excrements is 1.771 m³ CH₄ at 0°C and 1 013.25 hPa while the actual daily methane yield of droppings is 1.739 m³ CH₄ at 0°C and 1 013.25 hPa, i.e. practically identical, because the yield from urine organic matters was not included in the actual daily methane yield. Because the anaerobic degradability of the used feed mixture and horse droppings is practically identical, it is obvious that besides the enteric fermentation according to the reaction CO₂ + 4 H₂ → CH₄ + 2 H₂O by hydrogenotrophic methanogens no classical anaerobic digestion takes place in the digestive tract of horses; it means that the horse breeding sector is not a factor contaminating the atmosphere by methane.

Marginal economic values for production and reproduction traits of pigs were estimated applying a bio-economic model to Hungarian commercial sow herds with integrated fattening of piglets. Data collected between 2002 and 2008 were used for the calculation. Marginal economic values (in € per unit of the trait per sow per year) estimated for fattening days in the station test, age at the end of the field test, lean meat percentage in the carcass, percentage of valuable cuts in the carcass and the number of piglets born alive were 2.84 €/day, 2.71 €/day, 22.45 €/%, 28.81 €/% and 54.22 €/piglet in the first litter, respectively.

Twenty-four Czech dairy farms were visited to record lameness prevalence and to identify factors associated with high lameness prevalence at the farm level and/or increased lameness risk at the level of individual cows. All cows were checked for lameness and forty cows per farm were examined for overgrown claws, body dirtiness and skin lesions. The farm environment was scored between 1 (excellent) to 5 (very poor) in three different aspects: floor slipperiness, cow care quality, and housing quality. Data on hoof trimming schedules were obtained from farm managers. Lameness prevalence on farms was in a wide range from 6% to 42% (median 22%). At the farm level, floor slipperiness and poor animal care were associated with high lameness prevalence (Spearman correlations, P < 0.05), and the proportion of cows with overgrown claws tended to be associated with it (P < 0.10). The reported time schedules of hoof trimming (continuous trimming applied or not; and time elapsed since the whole herd was trimmed) were unrelated to either the prevalence of overgrown claws or the prevalence of lameness. Within farms, cows with overgrown claws and dirty cows were at an increased risk of being lame (multiple logistic regression, P < 0.05) and cows with skin lesions tended to be more lame (P < 0.10). The risk of lameness had an inverted U-shape dependence on age (P < 0.05), with cows at 7-8 years of age being the most endangered by lameness. We conclude that there is a large potential for lameness reduction on some Czech dairy farms through improving the cow care and reducing floor slipperiness, and that within farms, cows with overgrown claws and also dirty cows and cows with skin lesions should be given special attention since they are more likely to get lame.

Three groups of Brown fattened young bulls were studied, comparing the effects of rearing method (suckled vs. bucket reared) and of slaughter weight (400 vs. 480 kg). Suckled animals had higher fatness scores (2.2 vs. 1.3), more dissectible fat (14.5 vs. 9.1%), and higher intramuscular fat content (7.8 vs. 4.6%DM), accompanied by better scores in sensory tenderness (5.2 vs. 3.8) than did the bucket-reared ones. Animals slaughtered at a heavier weight showed a higher dressing percentage (57.5 vs. 53.8%), conformation score (9.2 vs. 6.2), and fat content (fatness score, dissectible fat and intramuscular fat). The meat from animals in the heavier group had lower a* (12.4 vs. 14.2) and higher b* (10.8 vs. 12.9) indexes, as well as higher scores in most sensory traits than the lighter ones.

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.