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This study is to explore the effects of natural tannin (NBT) on intestinal injury in piglets challenged with enterotoxigenic Escherichia coli (ETEC). Thirty-two 7-day-old piglets were divided into four groups: I) control group, piglets were fed a basic diet without challenge; II) ETEC group, piglets were fed a basic diet and challenged with enterotoxigenic E. coli; III) NBT + ETEC group, piglets were fed a basic diet with supplementation of 2 g/kg NBT and challenged with enterotoxigenic E. coli; and IV) ZnO + ETEC group, piglets were fed a basic diet with supplementation of 3 g/kg ZnO and challenged with enterotoxigenic E. coli. Results showed that diarrhoea rate was significantly increased in ETEC group, whereas it was decreased after NBT supplementation (P < 0.05); NBT supplementation significantly increased the average daily gain of ETEC-infected piglets. ETEC group showed damaged intestinal morphology (as indicated by decreased villus height, surface area and increased crypt depth) and barrier function (as indicated by decreased d-xylose content and increased diamine oxidase activity), induced oxidative stress (as indicated by increased myeloperoxidase activity) while supplementation of NBT had an obvious impact on the recovery of intestinal function and alleviated the oxidative damage. Further analysis showed that NBT could decrease the expression of genes related to intestinal injury (matrix metalloproteinase-3), and specifically upregulate the expression of oxidative stress-related genes (nuclear factor erythroid 2-related factor 2 and hypoxia inducible factor-1). Overall, dietary supplementation of NBT relieved intestinal injury and oxidative stress in piglets challenged with ETEC. NBT could be an alternative to ZnO as a feed additive in piglet diet.

This research paper addresses the hypothesis that the peptidoglycan recognition protein 1 (PGLYRP1) gene polymorphism (Tyr76His; dbSNP ID: ss104796364) has an influence on some performance traits and causes of culling in Polish Holstein-Friesian red-white cows. The study involved 134 cows kept on a farm in the south-west of Poland. PGLYRP1 genotypes TT, CT, and CC were detected. It was shown that compared with cows with genotypes CT and TT, the individuals with genotype CC were characterised by higher lifetime yields and higher amounts of lactation milk, fat, and protein. A beneficial effect of genotype CC, compared with genotype TT, was also noted in the case of the lifespan and, consequently, the length of the productive life and the average number of lactations. Diseases of the musculoskeletal system (genotypes CC and TT) and disorders of the reproductive system (genotype CT) were the most common causes of culling. An essential practical observation was the potentially higher susceptibility of cows with genotype CC to mastitis, which resulted in the necessity to cull over one-fifth of the animals in this group. Simultaneously, no cows in this group were culled due to low performance or metabolic, gastrointestinal, and respiratory diseases. Therefore, the PGLYRP1 gene seems to be a promising potential herd health marker; however, to consider it the main gene, it is necessary to extend the investigations to include more individuals and other breeds of dairy cattle.

The gilt development level is a critical factor for profitability in the pig industry. To evaluate the impact of different gilt development levels on the age structure and production efficiency of female herds we used the performance data of a pig farm that was simulated over a ten-year period, with current production statistics from the Chinese pig industry as a basis for the model. In a herd of 600 breeding sows, we compared age structure, number born alive (NBA), longevity and sow lifetime productivity in three scenarios with gilt culling rates of 10%, 20%, and 30%. The results show that the gilt development has no significant effects on the age structure. The gilt development had no significant effects either on sow reproductive performance or production efficiency. However, the annual replacement rate, longevity, and sow lifetime productivity varied significantly in the three levels of gilt development (P < 0.01). We conclude that the gilt development is closely related to herd turnover and reproductive performance, and ultimately affects the cost of pig production. Gilt development is, therefore, an extremely important factor in an integrated pig production system.

The aims of this study were to examine bacterial communities in relation to the rumen digestion of rice straw and to understand how concentrate supplements affect gut bacteria involving the digestion of a rice straw-based diet. The substrates were rice straw (RS) alone (experiment 1) and RS with 25% concentrates (barley and kidney beans) (experiment 2). The genomic DNA was collected to determine bacterial diversity by conducting denaturing gradient gel electrophoresis (DGGE). V6–V8 region group-specific (Clostridium and Bacteroides) primers were employed in the analyses. The DGGE band pattern was subjected to cluster analysis to demonstrate the similarity and difference between dietary treatments and solid-liquid fractions. Fibre digestibility, gas production, and volatile fatty acid (VFA) concentration were increased with incubation time. The differences between solid and liquid fractions were great in total bacteria, Clostridium, and Bacteroides communities. Clostridium and Bacteroides communities appeared unaffected by incubation time, whereas great differences existed between solid and liquid fractions throughout incubations (experiment 1). Barley and kidney bean supplements increased gas production and lowered rumen fluid pH, whereas changes in VFA concentration were significant only for kidney bean supplement. The Clostridium, and Bacteroides groups were affected by barley and kidney beans in the liquid fraction. However, the solid fraction was stable (experiment 2). These results indicate a rigid and stable community structure of Clostridium and Bacteroides groups involved in the digestion of rice straw-based diets in the rumen. Distinctive differences between solid and liquid fractions were described; hence, separate analyses of two fractions may greatly help understand the relationship between fermentation patterns and microbial communities in the rumen.

Myostatin (MSTN) is a negative regulator of skeletal muscle growth and development. A significant increase in skeletal muscle was observed in Mstn^-/- mice compared with wild-type mice. So far, there has been no report on porcine MSTN mutations leading to skeletal muscle hypertrophy. In this report a MSTN frameshift mutation missing 11 nucleotides in exon 2 was introduced into Meishan pigs by zinc finger nuclease (ZFN) technology. ZFN-edited MSTN^-/- Meishan pigs were successfully produced by a cloning method of somatic cell nucleus transfer. Results from slaughter experiments indicated that lean meat yield increased 16.53% in about 80 kg (10-months-old) MSTN^-/- Meishan sows compared with their corresponding wild-type counterparts. The lean percentage of carcass from MSTN^-/- sows was 61.20% vs 48.25% for MSTN^+/- sows and 44.67% for wild-type sows. The fat of MSTN^-/- sows was significantly lower than that of MSTN^+/- and wild-type sows. The loin eye area of MSTN^-/- Meishan sows (56.42 cm²) was greater than that of MSTN^+/- (37.39 cm²) and wild-type (26.26 cm²) sows. The muscle fibre area of longissimus muscle in wild-type Meishan sows (1 946 μm²) was significantly greater than that of MSTN^+/- (1 324 μm²) and MSTN^-/- (1 419 μm²) sows. Moreover the significantly increased skeletal muscle in these MSTN^-/- Meishan sows was mainly due to the increase in the number of myofibres rather than to hypertrophy. Compared with wild-type Meishan sows, it was noted that myofibres had transformed from type I to IIB in MSTN^-/- Meishan sows. Our present study demonstrated that frameshift mutation in MSTN by ZFN technology led to a significant increase in muscle mass and a significant decrease in fat content in Meishan sows.

Modern dairy farming is characterised by high selection intensity and the use of a limited number of bulls-producers. This increases the likelihood of widespread genetic defects in livestock populations. Genome-wide studies have identified DNA loci associated with the disruption of foetal embryonic development and its death, which have been called "fertility haplotypes". The aim of this study is to analyse the occurrence of АН1 haplotype or rs475678587 in Ayrshire bulls (n = 186) used in the artificial insemination system of Russia and to evaluate the reproductive and productive qualities of their daughters. The proportion of genetic defect carrier bulls in the analysed sample cohort was 16.66%. Analysis of the proportion of carriers of unwanted haplotype depending on the place of birth of the bull for service showed that the highest frequency was observed in bulls of Canadian origin (26.66%). Based on data on 97 478 cow and heifer calvings, stillbirth and abortion rates were analysed and cow reproduction rates were based on an AH1 status for the bull-father and bull for service. We observed a significant increase (P < 0.05 and P < 0.001) in the incidence of stillbirths when crossing the daughters of AH1-C bulls with AH1-C bulls. There was no negative association of abortion rates and reproductive qualities with AH1 haplotype. The high incidence of AH1 haplotype among animals of Ayrshire breed requires regular screening for the carriers of this haplotype not only among bulls, but also in cows.

Dairy farming is deeply affected by climate change, especially by rising temperatures and heat waves, poorer availability of quality food and water, and the spread of new diseases and pests outside their original ecological niche. Their impact can be mitigated not only by changes in technologies, management and treatment, but also by breeding and selection of more resilient cows. General resilience encompasses the animal's capacity to cope with environmental, social and disease challenges. It is described as the capacity of the animal to be minimally affected by a disturbance or to rapidly return to the physiological, behavioural, cognitive, health, affective and production states that pertained before exposure to a disturbance. As disturbances can be of different natures, general resilience is a composite trait consisting of different resilience types according to the nature of the disturbance. Resilience can be quantified through time series data that capture fluctuations in the daily performance. Recent studies have worked with deviations in the daily milk yield and daily live weight from optimal performance or have focused on the assessment of the daily activity in terms of the daily step count. To observe the duration and magnitude of the response to perturbance, two indicators were suggested: the autocorrelation (r_auto) and the natural logarithm of deviations (LnVar). Based on the daily milk yield deviations, both indicators have shown sufficient genetic variabilities with the estimated heritability ~0.1 for r_auto and ~0.2 for LnVar. Low values of both indicators were genetically related to better udder health, better hoof health, better longevity, better fertility, higher body condition score, less ketosis but also lower milk yield level. The selection for improved resilience could benefit from the use of genomic information as several genes and biological pathways associated with disease resilience and resilience to heat stress have already been identified. The presented results suggest that the integration of resilience into the cattle breeding programmes would improve the capacity of the dairy industry to cope with global climate change.

This study evaluated the productive performance, blood parameters and antioxidant status of hyperprolific sows fed control diet or diet supplemented with brown seaweed and polyphenol mixture (SPM). Ninety-six farrowing highly prolific sows (Topigs 20) were assigned to two dietary treatments from day 107 ± 2 days of gestation until weaning: control diet and the same diet containing 15 g/day of SPM. Sows fed SPM diet tended to have lower backfat losses (P = 0.06) than control sows. No difference was observed in daily feed intake. No difference in litter birth weight or number of piglets per litter was observed. In sows fed SPM, average daily gain and weaning body weight of piglets were increased (P < 0.05). Haematochemical parameters, haptoglobin and blood total antiradical activity were not affected (P > 0.05) by dietary treatment. The paraoxonase-1 activity was higher (P < 0.05) in SPM sows than in the control. At the subsequent farrowing, the total number of piglets born was higher (P < 0.05) in sows fed SPM than in the control. Overall, these data suggest that dietary plant polyphenols and brown seaweeds improved the weaning weight of piglets and the total number of piglets born at the subsequent farrowing, modulating oxidative stress in lactating highly prolific sows.

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.

Cadmium (Cd) is a toxic heavy metal, discharged into environments naturally or anthropogenically, where industrial and agricultural revolutions have led to serious Cd pollution into the environment. Poultry feed may be contaminated by Cd due to its presence in concentrates and supplements, and also in the machinery and equipment used in feed production and processing. After absorption in the digestive system, Cd largely accumulates in kidneys, liver, bones and other organs and causes irreversible damage to these organs. Higher doses of Cd in the poultry diet reduced feed intake, body weight, bone mineral density, egg production and eggshell quality. Selenium (Se) is an essential micronutrient and important component of a variety of antioxidant enzymes, with the ability to antagonize metal toxicity including Cd. Hence, in the current review, we try to summarize recent information about the toxicological effects of Cd and provide updated information about the role of Se as an effective strategy in reducing Cd toxicity in poultry.

The aim of the present study was to compare carcass characteristics and meat quality of fast- (Ross 308), medium- (Hubbard JA757) and slow-growing (ISA Dual) chickens (n = 1 980). When the chickens reached an average live weight of 2 kg, 40 birds (males to females, 1 : 1) of each genotype were randomly selected and slaughtered for carcass analysis. Pectoralis major (PM) muscle samples were taken to determine the physical and chemical parameters of the meat quality. The fast- and medium-growing genotypes had higher (+3.24% and +3.84%, respectively) dressing out percentages than the slow-growing chickens. As expected, the breast percentage significantly decreased in the order of fast growth > medium growth > slow growth. The abdominal fat percentage was the lowest in Ross 308 chickens, but the abdominal fat percentage in JA757 and ISA Dual chickens did not differ. For edible organs, fast- and medium-growing chickens had heavier hearts and livers than slow-growing chickens. In contrast, ISA Dual chickens showed heavier gizzards. Genotype dramatically affected the chemical composition of PM muscle. The ISA Dual chickens exhibited a significantly higher proportion of dry matter and protein and lower ether extract and cholesterol content than Ross 308 chickens, with intermediate values for JA757 chickens. The ISA Dual group had a lower ash content than Ross 308 and JA757 groups. In terms of physical parameters, the ISA Dual chickens had higher lightness and yellowness and lower redness, pH 24, and cooking loss than those of the other genotypes. Concerning all genotypes, the shear force values increased from fast- to slow-growing chickens. In conclusion, this study found a difference between the genotypes. Although the slow-growing chickens showed the lowest dressing out and breast percentages compared with the other genotypes, the breast meat of the slow-growing chickens had more favourable nutritional properties.

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 aim of this study was to examine the effects of ozonation on the water quality, and growth, blood biochemistry, antioxidant capacity and survival of pikeperch (Sander lucioperca) reared in a recirculation aquaculture system for 30 weeks. A group without ozone treatment was used as a control. The ozone application led to a significant reduction of the water chemical oxygen demand, biological oxygen demand and unsuspended solids concentration. The results revealed that an ozone treatment as a water treatment method has a positive influence on the intensive culture of pikeperch ensuring a higher survival rate (77%) compared to the non-treated control group (67.2%). Moreover, the ozonation prevented fin damage to a large extent and reduced the prevalence of an Ichthyophthirius multifiliis infection. Furthermore, the ozone application led to a reduction in the thiobarbituric acid reactive substance level and enhanced the superoxide dismutase activity in the fish gills. However, the effect of ozonation was null on the plasma biochemical parameters. Overall, these findings suggest that an ozone treatment, using adequate technological equipment to destroy the residual ozone, improves the water quality and protects pikeperch against any possible infection and fin damage in a recirculation aquaculture system.

Hens of the laying hybrid ISA Brown were used in the study with the objective to evaluate eggshell quality, microbial contamination of eggshells, and penetration of microorganisms into the egg content in different housing systems (enriched cage: 60 hens, 10 hens per cage, 750 cm² per hen vs free range: 60 hens, 9 hens per m²) and at different hen ages (26 vs 51 weeks) during storage time (0, 2, 7, 14, and 21 days). A significant interaction between the housing system and age was observed in egg weight and most of eggshell quality measurements. However, microbial contamination and penetration were affected mostly by the housing system and storage time. The numbers of Escherichia coli (P < 0.001, 4.51 vs 2.75 log cfu/eggshell) and Enterococcus (P < 0.001, 2.56 vs 1.11 log cfu/eggshell), and the total number of microorganisms (P < 0.001, 5.04 vs. 3.65 log cfu/eggshell) were higher in free range eggs compared to enriched cage eggs, respectively. The counts of Escherichia coli (P < 0.001, 4.23 vs 2.91 log cfu/eggshell) and Enterococcus (P < 0.001, 2.31 vs 1.27 log cfu/eggshell) decreased with storage time. A positive correlation between the total number of pores and penetration of Escherichia coli in both housing systems was observed in the albumen. It can be concluded that the housing system and age of laying hens significantly affected eggshell quality. Microbial contamination presumably affects the penetration of microorganisms. The correlation between the number of pores and penetration is assumed to be affected by the microbial species.

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.

The aim of the study was to evaluate the effect of crossing Mecklenburger Schecke (MS) males with the maternal commercial line of HYLA rabbits on the growth performance, mortality and body and carcass components of fattened rabbits under intensive farming conditions. The control (C) group consisted of albino crossbred rabbits of the HYLA combination AB sires × CD dams. The tested (T) group (MS sires × HYLA CD dams) consisted of rabbit crosses between the MS sires and the same dam line as in the C group. Rabbits of both groups were raised and fattened under identical nutritional and management conditions. The crossing of MS males with the maternal line of HYLA rabbits led to the acceptable growth performance of rabbits in the T group. The higher slaughter weight of rabbits in the T group as compared to rabbits in the C group (P < 0.01) as associated with the higher weight of hot carcass and higher proportions of fore and intermediate parts of carcass (P < 0.01). On the contrary, HYLA rabbits had a higher proportion of the hind part of carcass (P < 0.001); yields of hind leg meat and musculus longissimus thoracis et lumborum were not influenced by the genotype. However, since higher mortality was found in rabbits of the T group during fattening, it is not possible to recommend the MS breed as a common sire line used under conditions of intensive farming at this moment. Regarding the rabbit sex, slaughtered females showed a higher proportion of liver and a lower dressing percentage associated with the worse carcass compactness compared to males.

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 aim of the present study was to optimize the conventional method of sperm freezing in liquid nitrogen (LN₂) vapour for successful cryopreservation of Wallachian ram sperm, the genetic resources of the Czech Republic. Sperm in straws were frozen using the conventional freezing method via a static exposure of sperm doses to LN₂ vapour, or by four different modified freezing methods. Under modified freezing, straws were frozen by a discontinuous, time-dependent decremental change in the distance between the straws and the surface of LN₂. The viability of sperm was evaluated by flow cytometry after sperm equilibration, and immediately after thawing. Besides the observed inter-sire and daily variation, the obtained results suggest the methodological weakness of the conventional freezing method via the static exposure of sperm doses to LN₂ vapour. With the use of the optimized freezing procedure, all parameters of thawed sperm were significantly (P < 0.05) improved in comparison with the conventional method: percentage of thawed sperm viability increased up to 48.3%, percentage of sperm with plasma membrane damage after thawing decreased to 6.58%, percentage of sperm with acrosome damage decreased to 24.4%, and percentage of sperm with deteriorated mitochondrial activity decreased to 6.28%. In conclusion, our results suggest that an optimized freezing procedure should be routinely used instead of the conventional method to cryopreserve Wallachian ram sperm.

This study was conducted to evaluate the effects of a toy on the behaviour and body weight of weaned pigs after mixing. Two groups (192 pigs in total, control: without toy; treatment: with toy placed on the floor) of weaned pigs housed in pens (1.8 m × 1.4 m, 4 pigs/pen) were This study was conducted to evaluate the effects of a toy on the behaviour and body weight of weaned pigs after mixing. Two were observed with the aid of video technology for nine consecutive hours in the early (days 1 and 2) and late (days 38 and 39) period after mixing. Bodyweight of pigs at the end of the study (Mann-Whitney U-test, Z = -2.46, P = 0.01) and the average daily gain (Z = -2.75, P < 0.01) were 10% higher in the treatment group than in the control group. The presence of the toy in the pen influenced the pig behaviours. In pens enriched with toys, there was an increase in feeding behaviour and a decrease in agonistic and belly nosing behaviours. Toy supply reduced negative social behaviours and thereby improved the bodyweight of weaned pigs. The results of this study suggest that toys used as environmental enrichment are useful for enhancing pig welfare and effective for farmers.

In the last decade, the pig sector in Slovakia has been changing continuously, especially in regard to the proportion of pigs coming from foreign breeding programs. These changes lead to changes in carcass characteristics and to a change in the distribution of carcasses within the classes of the Union scale for the classification of pig carcasses. Therefore, this study was undertaken to analyse the actual state of pig carcass classification in the Slovak Republic and to investigate the needs of updating the equations for the classification methods and possible steps to improve the quality of pork produced within the country. Results showed that an increased number of pig carcasses originated from Danish breeding program, and also from the Czech Republic and Poland. When compared to carcasses in 2009, these changes resulted in lower backfat thickness and higher muscle thickness of the longissimus dorsi muscle and thus higher lean meat content of carcasses. This results in a higher number of carcasses classified in the S and E classes. Slight differences between two instrumental classification methods were calculated. The study showed the need for updating the equations for classification methods, and also suggested possible further steps in order to improve the quality of pork.

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 effects of a simple saline solution prepared using two different pH (4.4 and 8.5) on sperm motility in burbot were investigated. Results were recorded during a 96-hour chilled storage (4°C) in 24-hour intervals. Measurements were focused on the detailed characteristics of motility using 12 parameters obtained from the Computer-assisted Sperm Analysis (CASA). Significantly higher progressive motility (pMOT), distance average path (DAP), distance curved line, distance straight line (DSL), average path velocity (VAP), curvilinear velocity, straight line velocity, and beat cross frequency (BCF) were observed with the activating solution buffered at pH 8.5 in comparison with pH 4.4. Already after 24 h a significant reduction was measured in pMOT (0 h: 49 ± 24%, 24 h: 12 ± 7%). Similar decreasing tendency was recorded only after 72 h in DAP (0 h: 26 ± 4 µm/s, 72 h: 19 ± 9 µm/s), DSL (0 h: 21 ± 5 µm/s, 72 h: 17 ± 8 µm/s), VAP (0 h: 59 ± 9 µm/s, 72 h: 43 ± 21 µm/s), and BCF (0 h: 28 ± 2 Hz, 72 h: 18 ± 10 Hz). The response of different investigated CASA parameters to different treatments varied in our experiments. According to our studies, numerous burbot sperm motility parameters are sensitive to chilled storage and to low pH of the activating solution. Our results could support the effective sperm quality assessment and successful artificial propagation process in burbot.

Bísaro pig, a local endangered swine breed, has gained popularity in the recent years. A complete pedigree was used to evaluate the population structure and investigate the current breed's genetic variability in two reference populations (AlivePop and AliveBpop). Since the breed's foundation, the number of registered animals, producers, and farrowing records has increased. The mean progeny size for sires was 116.17 ± 210.81, and 3.24% of the breeding boars originated 26.54% of all registered births showing a marked unbalanced use of certain sires. The mean calculated equivalent generations was 4.54, and 98.1% of all the animals had known parents, indicating a good degree of pedigree completion and depth. Approximately half of the individuals were inbred, with average inbreeding values of 10.41, 9.02, and 8.58% for the whole and reference populations, respectively. Considering both reference populations, a low effective founder/ancestor ratio was obtained (1.12), showing a well-balanced founder/ancestor contribution, and subsequent genetic transfer. However, the effective founder/founder ratio was particularly low (0.06 and 0.12) compared with other native breeds. The founder genome/effective founder ratios were 0.37 and 0.41 for AlivePop and AliveBpop. Contrarily to the whole population, the random genetic drift weighted significantly more than the drift due to unequal founder contribution in the reference populations. The effective population size based on the increase in coancestry ranged from 62.39 and 54.66, and 16.74 and 24.84 based on the increase of individual inbreeding, for the whole and reference populations. The genetic conservation index steadily grew over the years with a mean value of 6.53 for the whole pedigree. Genetic variability losses and diffuse structuring might have occurred in the Bísaro population. Notwithstanding, the recent genetic variability indicators seem positive, yet supported by an open herdbook policy. These characteristics must be taken into account to define future mating policies and selection programs.

Exploration of genetic variance has mostly been limited to additive effects estimated using pedigree data and non-additive effects have been ignored. This study aimed to evaluate the performance of single nucleotide polymorphisms (SNPs) marker models in the mixed and orthogonal framework including both additive and non-additive effects for estimating variances and genomic prediction in four diabetes-related traits in heterogeneous stock mice. Models have performed differently in detecting SNPs affecting traits. Dominance variances explained over 14.7 and 3.8% of genetic and phenotype variance in a Genomic prediction and variance component estimation method (GVCBLUP) framework. Reliabilities of additive Genomic best linear unbiased prediction model (GBLUP) in different traits ranged from 44.8 to 66.6%, for GVCBLUPs framework including both additive and dominance effects (MAD), and 46.1 to 69% for the model including additive effect (MA). Dominance GBLUP reliabilities ranged from 6 to 26.4% for MAD and from 22.5 to 50.5% in the model including dominance (MD). MA and MD had higher reliability for additive and dominance GBLUPs compared to MAD. Reliabilities of GBLUPs in MAD and MA for all traits were not significant except for growth slope (P < 0.01). In orthogonal framework models, epistasis variances accounted for a greater proportion (87.3, 89.1, 95.5, and 77.2%) of genetic variation for end weight, growth slope, body mass index, and body length, respectively. Heritability in a broad sense was estimated at 1.12, 1.67, 3.64, and 2.0%, in which non-additive heritability had a significant contribution. Genetic variances explained by dominance using GVCBLUPs were 16.8, 29.4, 14.6, and 14.9% for the traits. Generally, the non-additive models had a lower value of deviance information criterion (DIC) and performed better in estimating the variance component. Comparing the estimated variance by orthogonal framework models confirmed the results previously estimated by GVCBLUPs, with the difference that the estimates were shrinking. Following significant SNPs affecting diabetes-related traits by post-genome-wide studies could reveal unknown aspects and contribute to genetic control of the disease.

The effect of artificial conditions of a short daylight period (16 h darkness (D): 8 h light (L)) and exogenous melatonin on milk yield parameters of sheep during spring and summer was examined to determine the impact of using sheep for milk on the secretion level of gonadotrophic hormones. The research was conducted on 60 sheep lambed in February. After raising the lambs, the sheep were divided into 3 groups and assigned for dairy use (May-September). The mothers in the control Group 1 (G1) were maintained under natural daylight conditions. The sheep in Group 2 (G2) were maintained under conditions of an artificial photoperiod (16 h D : 8 h L). Meanwhile, the mothers in Group 3 (G3) were given melatonin implants. A 6-hour collection of blood from 6 sheep of each group was performed every 4 weeks. The concentrations of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) in plasma were measured using radioimmunoassay. The average LH concentration in G1 gradually increased since May (5.32 ± 0.2 ng/ml), reaching the highest value in August (6.70 ± 0.2 ng/ml). In G2, the increase in LH occurred 4 weeks after the introduction of the 16 h D : 8 h L condition (6.26 ± 0.2 ng/ml). The maximum LH concentration in G3 was noted in August (7.31 ± 0.2 ng/ml). The average FSH concentration in G1 gradually increased since May (6.59 ± 0.2 ng/ml), reaching the highest value in August (10.50 ± 2.6 ng/ml). In G2, there was a significant increase in the FSH concentration in June (9.00 ± 0.3 ng/ml). In the final period during lactation, the FSH concentrations in G2 (13.51 ± 1.3 ng/ml) and G3 (13.60 ± 1.9 ng/ml) were higher than in G1. The results indicate that using sheep for milk does not inhibit the secretion of gonadotropic hormones induced by the simulation of short daylight conditions and exogenous melatonin.

An effective realization of breeding programs in zoos is strongly determined by completeness of animal pedigree information. The knowledge of pedigree structure allows to maintain optimal genetic variability of a given population. The aim of this study was to estimate the parameters describing the pedigree structure of American bison housed in zoos in the context of further management of the population. Finally, 4269 American bison were analysed (1883 males, 2217 females, and 169 with unknown sex). The registered animals were born between years 1874 and 2013. The following pedigree parameters were estimated: number of fully traced generations, number of complete generations equivalent, index of pedigree completeness, individual inbreeding coefficients, increase of inbreeding for each individual, effective population size, and genetic diversity. The maximum number of fully traced generations was 3 (the mean value is 0.693). The mean inbreeding coefficient for the population studied was 3.26%, whereas individual increase in inbreeding ranged from 0 to 25.12%. Although the pedigree parameters (including the inbreeding level) in the American bison obtained in the present study seem to be acceptable (from the perspective of other wild animal populations), they can be over/underestimated due to incomplete pedigree.

Twelve adult Slovak warmblood sport horses were used to study the effect of dried grape pomace (DGP) on health through blood serum biochemical indicators, and on apparent total tract digestibility of dry matter (DM), organic matter (OM), crude protein (CP), acid detergent fibre (ADF) and neutral detergent fibre (NDF). The digestibility analysis was carried out by two in vivo methods, total faeces collection (TFC) and using lignin as a marker (ADL). Animals were divided into 3 groups: control group (C, without supplementation), experimental group 1 (E1, feed rations + 200 g of DGP) and experimental group 2 (E2, feed rations + 400 g of DGP). In animals, no health problems were detected during the trial. Of the blood serum indicators, only the concentrations of potassium (increase in E2 group compared to C group) and alanine aminotransferase (decrease in E2 group in comparison with E1 and C group) were affected (P < 0.05). The ADL method resulted in underestimated digestibility coefficients due to low recovery rates of lignin (less than 90%) in C group and E1 group. According to TFC, in E1 group higher digestibility coefficients were detected for DM, OM and CP (P > 0.05) compared to C group. However, in E2 group lower digestibility of all the studied nutrients was found (P > 0.05) in comparison with C group and E1 group. These results suggest that DGP could be used in horse diets up to 200 g without negative effect on their health and for a possible digestibility improvement of some nutrients.

The associative effects (AE) between concentrate (C), peanut shell (P) and alfalfa (A) were investigated by means of an automated gas production (GP) system. The C, P and A were incubated alone or as 40 : 60 : 0, 40 : 45 : 15, 40 : 30 : 30, 40 : 15 : 45, 40 : 0 : 60 and 30 : 70 : 0, 30 : 55 : 15, 30 : 40 : 30, 30 : 25 : 45, 30 : 10 : 60, 30 : 0 : 70 mixtures where the C : roughage (R) ratios were 40 : 60 and 30 : 70. Samples (0.2000 ± 0.0010 g) of single feeds or mixtures were incubated for 96 h in individual bottles (100 ml) with 30 ml of buffered rumen fluid. GP parameters were analysed using a single exponential equation. After incubation, the residues were used to determine pH, dry matter digestibility (DMD), organic matter digestibility (OMD), volatile fatty acids (VFA) and ammonia nitrogen (NH₃-N) of the incubation fluid, and their single factor AE indices (SFAEI) and multiple-factors AE indices (MFAEI) were determined. The results showed that group of 30 peanut shell had higher SFAEI of GP_{48 h}, DMD, OMD and total volatile fatty acids (p < 0.05) and MFAEI (p < 0.05) than groups 60, 45 and 0 when C : R was 40 : 60. The group of 10 peanut shell showed higher SFAEI of GP_{48 h}, DMD and OMD (p < 0.05) than groups 70, 55 and 40 and MFAEI (p < 0.01) when C : R was 30 : 70. It is concluded that optimal SFAEI and MFAEI were obtained when the C : P : A ratios were 40 : 30 : 30 and 30 : 10 : 60.

This study aimed to evaluate the impact of selection on the genome structure of beef cattle through identification of selection signatures reflecting the breeding standard of each breed and to discover potential functional genetic variants to improve performance traits. Genotyping data of six beef breeds (Aberdeen Angus, Hereford, Limousin, Charolais, Piedmontese and Romagnola) were used to perform genome-wide scans for selection signatures. The approaches applied were based on an assumption that selection leads to linkage disequilibrium or to a decrease of genetic variability in genomic regions containing genotypes connected with favourable phenotypes. Thus, the selection signatures were analysed based on Wright's F_ST index, distribution of runs of homozygosity segments in the beef genome and determination of linkage disequilibrium variability between breeds. The number and length of detected selection signals were different depending on the breeds and methodological approaches. As expected due to the breeding goals of analysed breeds, common signals were located on autosomes 2, 6, 7, 13 and 20 close to the genes associated with coat colour (KIT, KDR), muscle development (GDF9, GHRH, GHR), double muscling (MSTN), meat tenderness (CAST) and intramuscular fat content (SCD). But, across the genomes of analysed breeds, unique selection signals were found as well. The subsequent analysis of those single nucleotide polymorphism markers can be beneficial for the genetic progress of studied breeds in future.

In order to improve the gut microbiome of calves, probiotic bacteria can be fed as active living-cells (fermented milk), or as live but inactive (freeze-dried) cultures. Ten bifidobacterial strains with suitable probiotic properties (as determined in our previous study) were tested for survival during the freeze-drying process, and screened for their ability to ferment cow's milk. The viability of both freeze-dried and live-cell cultures during storage was also tested. All of the strains tested were able to ferment cow's milk, with average counts of 8.26 ± 0.62 log CFU/ml. Eight out of the ten strains were able to survive in milk for 2 months in counts higher than 10⁶ CFU/ml. Bifidobacteria showed high viability following the freeze-drying process, with average numbers of 9.03 ± 0.22 log CFU/vial and did not decrease after 12 months of storage. The mixture of rifampicin-resistant variants of bifidobacteria (RRBs) was fed to 2-day-old dairy Charolais calves in the form of living-cells, or as freeze-dried bacteria. The control group was given no probiotics. Survival of the RRBs administered and the numbers of other bacterial groups in faecal samples was monitored by culturing. Bifidobacteria that were administered passed successfully through the upper parts of the gastrointestinal tract, and were found in numbers higher than 10⁹ CFU/g for two weeks. RRBs colonized the intestines of calves for at least 63 days in both treatment groups. Significantly higher total counts of bifidobacteria were found in the treated groups, compared to the control group. Reduction in Escherichia coli and total coliforms numbers, and an increase in lactobacilli counts were observed in both experimental groups following the application of the probiotic mixtures. Our results show that both forms of administering probiotic bifidobacteria to calves are effective, but that the freeze-dried form is more suitable from a practical viewpoint.