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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.

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.

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 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.

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 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.

In this study, we aimed to estimate and compare genetic diversity of two native draught horse breeds and check the possible influence of Noriker breed population on these native breeds. Genetic analyses of relationships and admixture were performed in two native endangered draught horse populations (Silesian Noriker and Czech-Moravian Belgian horses) and one open breed (Noriker). Totally 104 alleles from 13 microsatellite loci were detected in 1298 horses. The average number of alleles per locus was the highest in the Czech-Moravian Belgian horse (7.62) and the lowest in the Silesian Noriker (7.31), the differences were non-significant, whereas the observed and expected heterozygosities per breed ranged from 0.680 (Czech-Moravian Belgian) to 0.719 (Noriker) and from 0.678 (Silesian Noriker) to 0.714 (Noriker). The estimates of Wright's F_ST between each pair of breeds indicated a low level of genetic segregation. At the individual level across the analyzed population, formation of two clusters was observed with respect to historical breed development. Moreover, the membership probability outputs showed that the frequencies of alleles varied across the two main regions represented by the Czech-Moravian Belgian and other analyzed breeds. Our results indicated high genetic variability, low inbreeding, and low genetic differentiation, especially between Silesian Noriker and Noriker, which is caused by the high level of admixture. This high level of admixture was in accordance with geographical location, history, and breeding practices of the analyzed breeds. The Silesian Noriker and Noriker breeds seem to be the most genetically related and the decision to consider them as the same population is thus highly supported. The study provides data and information utilizable in the management of conservation programs planned to reduce inbreeding and to minimize loss of genetic variability.

Fish are a rich source of omega-3 polyunsaturated fatty acids (n-3 PUFAs) and thus, they should be an integral part of human diet at least twice a week. As a result, high attention has been devoted to the improvement of fatty acids (FA) content in the flesh of farmed fish through nutrition. Conversely, there are very few data on the potential of selective breeding to improve FA composition in fish. We estimated genetic parameters of fillet fatty acid content and performance traits in market size common carp cultured under semi-intensive pond conditions. The experimental stock arose through factorial mating of 7 dams and 36 sires. All families were reared communally. Pedigree was reconstructed with microsatellite markers, and 158 individuals were dressed out and selected for flesh FA composition analysis. Heritability estimates of total muscle fat, FA composition in total fat (TF) (n-3 PUFA-TF, PUFA-TF, EPA-TF - eicosapentaenoic acid, n-6/n-3 - omega6/omega3 PUFA ratio), and most performance traits were moderately heritable (h² = 0.23-0.41), and body weight was highly heritable (h² = 0.62 ± 0.20). Genetic correlations show that selection for faster growth would indirectly lead to fillet yield improvement (r_g = 0.50-0.62) while having little impact on muscle fat (r_g = 0.21). However, lipid quality in flesh would be affected: n-3 PUFA-TF would decrease and the n-6/n-3 PUFA ratio would increase. A likely interpretation is that faster growing genotypes consume more supplemental feed, which was poor in the beneficial FAs. For sustainable selective breeding, supplemental feed composition should be modified, so that faster growing carps would maintain an appropriate flesh quality.

The aim of this study was to analyse the genomic regions that have been target of natural selection with respect to identifying the loci responsible mainly for fitness traits across six alpine cattle breeds. The genome-wide scan for selection signatures was performed using genotyping data from totally 465 animals. After applying data quality control, overall 35 873 single nucleotide polymorphisms were useable for the subsequent analysis. The detection of genomic regions affected by natural selection was carried out using the approach of principal component analysis. The analysis was based on the assumption that markers extremely related to the population structure are also candidates for local adaptation potential of the population. Based on the expected false discovery rate equal to 10% up to 1138 loci were identified as outliers. The strongest signals of selection were found in genomic regions on BTA 1, 2, 3, 6, 9, 11, 13, and 22. Most genes located in the identified regions have been previously associated with immunity system as well as body growth and muscle formation that mainly reflect the pressure of both natural and artificial selection in respect to adaptation of analysed breeds to the local environmental conditions. The results also signalized that those regions represent a correlated selection response in way to maintain the fitness of analysed breeds.

The objective of this study was to investigate the effects of different sources and levels of zinc (Zn) on nutrient digestibility, plasma metabolites, and relative Zn bioavailability in male mink. Animals in the control group were fed a basal diet, consisting mainly of corn, soybean oil, meat and bone meal, and fish meal, with no Zn supplementation. Mink in the other 9 treatments were fed the basal diet supplemented with Zn from grade Zn sulfate (ZnSO₄^. 7H₂O), Zn glycinate (ZnGly), or Zn pectin oligosaccharides (ZnPOS) chelate at concentrations of either 100, 300, or 900 mg Zn/kg dry matter. The results showed that zinc levels increased the AD of fat linearly (P < 0.05). The AD of fat in Zn-900 was higher (P < 0.05) than that of the control. Fecal Zn and urinary Zn were affected by dietary Zn addition (P < 0.01). Moreover, Zn supplementation increased Zn retention compared with the control group (P < 0.05). The N retention in ZnPOS was higher (P < 0.05) than that of the control. The effect of Zn level was linear (P < 0.01) for N retention. In addition, the activity of alkaline phosphatase was higher in groups supplemented with 900 mg/kg Zn (P < 0.05) compared with the control group. There were significant interactions (P < 0.05) among Zn sources on the activity of Cu-Zn superoxide dismutase (Cu-ZnSOD). Compared with ZnSO₄, relative bioavailability values were 148% and 173% for ZnGly and ZnPOS, respectively, based on Cu-ZnSOD activity. In conclusion, our data show that the relative bioavailability of ZnPOS was greater than that of ZnSO₄^. 7H₂O and ZnGly and Zn supplementation can enhance the Cu-ZnSOD of male mink, and mink can efficiently utilize ZnGly and ZnPOS.

Research material included data on gestation length of 15 436 cows of Polish native breeds. These were: White Backed (BG; 324 records), Polish Red (RP; 5396 records), Polish Black and White (ZB; 3508 records), and Polish Red and White (ZR; 6208 records). The calvings took place in 2005-2009, and we analysed two calving seasons, lactation number, the degree of calving difficulty, sex, and body weight of newborn calves. The effect of birth year on gestation length and birth weight of offspring was statistically significant, whereas calving season had statistically highly significant effect on both. Gestation length in the analysed breeds was 281.02, 283.35, 280.5, 281.53 for BG, RP, ZB, and ZR, respectively. The birth body weight heritability was 0.13 (RP), 0.33 (ZB) and 0.40 (ZR).

Main aim of this retrospective study was to determine the role of the level of meeting the requirements in net energy of lactation (NE_L) and utilizable crude protein at the duodenum (uCP) in weeks 3-17 postpartum on the interval from parturition until conception (IUC) in dairy cows. We compared intakes and balances of NE_L and uCP, body weight change, metabolic status, reticuloruminal pH, and serum amyloid A (SAA) as a systemic inflammation marker in 30 dairy cows differing in the IUC length (i.e., short (S; n = 8), medium (M; n = 11), and long (L; n = 11) IUC for cows confirmed pregnant within week 10 or between weeks 11 and 17 postpartum, or thereafter, respectively). Data showed that the level of meeting the requirements in NE_L and uCP in weeks 3-10 postpartum was instrumental in shortening the IUC in the cows pertaining to S IUC group (P ≤ 0.03). As an average, during this period the S cows met 104 and 110% of their requirements in NE_L and uCP, respectively. In contrast, the M and L cows met 96 and 95% of NE_L as well as 104 and 101% of uCP requirements, respectively. The M cows showed higher milk and blood urea nitrogen (P = 0.04), and also lower SAA concentration (P = 0.05) compared to L cows. In conclusion, exceeding the requirements in both NE_L and uCP in weeks 3-10 postpartum significantly shortened the IUC to less than 10 weeks. The shorter IUC in M vs L cows went along with improved protein status and lesser systemic inflammation in week 6 postpartum in these cows.

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.

This study estimated the genetic parameters for reproductive and performance traits and determined which ones can be used as selection criteria for egg production in laying hens using the Bayesian inference. The data of 1894 animals from three generations of White Leghorn laying hens were analyzed for fertility (FERT), hatchability (HATC), and birth rate measurements at 60 weeks of age (BIRTH), body weight at 16 and 60 weeks of age (BW16 and BW60), age at sexual maturity (ASM), egg height/width ratio, weight, and density at 28, 36, and 40 weeks of age (RHW28, RHW36, RHW40, WEGG28, WEGG36, WEGG40, DENS28, DENS36, and DENS40, respectively) traits. The genetic parameters were estimated by the Bayesian inference method of multi-trait animal model. The model included the additive and residual genetic random effects and the fixed effects of generation. The a posteriori mean distributions of the heritability estimates for reproductive traits ranged from 0.14 ± 0.003 (HATC) to 0.22 ± 0.005 (FERT) and performance from 0.07 ± 0.001 (RHW28) to 0.42 ± 0.001 (WEGG40). The a posteriori mean distributions of the genetic correlation between reproductive traits ranged from 0.18 ± 0.026 (FERT and HACT) to 0.79 ± 0.007 (FERT and BIRTH) and those related to performance ranged from -0.49 ± 0.001 (WEGG36 and DENS36) to 0.75 ± 0.003 (DENS28 and DENS36). Reproductive and performance traits showed enough additive genetic variability to respond to selection, except for RHW28. This trait alone would have little impact on the genetic gain because environmental factors would have a higher impact compared to those from the additive genetic factors. Based on the results of this study, the selection applied on the BIRTH trait can be indicated to improve FERT and HATC of eggs. Furthermore, the use of the WEGG40 could improve egg quality in this population.

Assessment of seminal oxidative stress indicators is emerging as a valuable prognostic tool in assisted reproductive technology. We investigated levels of oxidative stress caused by reactive oxygen species (ROS) and the antioxidant enzyme defence system comprising superoxide dismutase (SOD), glutathione reductase (GR), and glutathione peroxidase (GPx) in seminal plasma (SP) of common carp Cyprinus carpio and rainbow trout Oncorhynchus mykiss over the course of the spawning season. Oxidation was determined in lipids and proteins by assessing thiobarbituric acid reactive species (TBARS) and the 2,4-dinitrophenylhydrazine carbonyl groups, respectively. Levels of SOD were assessed by the autoxidation of pyrogallol. Determination of GR and GPx was based on the rate of NADPH oxidation. We observed clear alterations in lipids and proteins over the course of the spawning season in both species. The highest levels of TBARS and CP were recorded late in the season. SOD was not significantly altered in either species. The activity of GR was higher in carp SP late in spawning compared to other times (P < 0.05), while in rainbow trout, GR significantly increased (24.13 ± 2.8 mU/mg protein) in mid-season. A significantly lower GPx activity (9.18 ± 1.32 mU/mg protein) was found in rainbow trout SP early in the spawning season, but no significant differences in GPx were observed over the course of the season in carp. These results provide further understanding of the role of fish SP antioxidants and present new data on the oxidant and antioxidant balance in SP during the spawning season that may be of value in the development of methods for artificial reproduction of teleost species.

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.

The population genetic evaluation of the Hungarian Hucul horse population was performed based on pedigree records. Herd book data of registered Hucul horses available up to 2016 were analysed using ENDOG (Gutierrez and Goyache 2005) and POPREP (Groeneveld et al. 2009) on the whole population (WP) as well as on the reference stock (RS) (breeding stock registered in 2016). Inbreeding coefficients were 5.57% (WP) and 7.18% (RS). Average relatedness was 10.39% in WP and higher in RS (12.67%). Effective population size was 52.32. Generation interval was 13.01 years for WP and 10.99 years for RS. The values for equivalent complete generations were 6.07 and 8.75, for the maximum number of generations 14.11 and 19.16, and for the number of full generations traced 3.77 and 5.50 for WP and RS, respectively. The effective number of founders (f_e) was 23 both for WP and RS. The effective number of ancestors (f_a) was 20 in WP and lower in RS (16). The f_a/f_e ratio was 0.869 in WP and 0.696 in RS. Founder genome equivalent (f_g) was 9.618 in WP and 5.790 in RS. The f_g/f_e ratio was 0.481 in WP and 0.361 in RS. The study revealed that both the inbreeding coefficient and the average relatedness were high. The above mentioned ratios indicated loss of genetic diversity in the Hungarian Hucul population.

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.

The aim of this study was to evaluate the potential of udder measurements for prediction of milk yield, milk components and somatic cell count in non-dairy Wallachian sheep. The study was performed on 38 ewes in the Beskids Mountains kept under extensive management on pasture. Milk production (MILK) as well as samples for milk component and somatic cell count determination were collected during two separate control days (42^nd day and 100^th day of lactation on average). Rear udder depth (RUD, cm), udder width (UW, cm), and teat length (TL, mm) were measured at each control day as well. Linear regressions of udder measurement characteristics showed a predictive character ability for MILK only. An increasing of 70 g MILK corresponded with a 1 cm increase of RUD (P < 0.01) or 1 cm increase of UW (P < 0.001). These positive linear relationships were supported by the positive partial correlation analysis between MILK and RUD (r = 0.503; P < 0.001) or MILK and UW (r = 0.627; P < 0.001). An increase of 1 mm TL was associated with a 10 g (P < 0.01) increase of MILK; however, correlations between these traits were not significant. Results of this study demonstrate an alternative way of MILK ability in non-dairy Wallachian sheep population in general. Correlation and regression analysis further estimated this expected potential in detail using udder measurement characteristics. Measurement of RUD and UW could serve as a tool for breeding and flock management in order to maintain and improve milk production; however, there was no obvious evidence for the prediction of milk composition characteristics and somatic cell count.

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.

Genetic relationship was analyzed between type traits and longevity measures in dual-purpose cattle. Data from 91 486 Czech Fleckvieh cows first calved between 2003 and 2009 were used. Longevity was defined as the actual number of lactations initiated per cow and also as functional longevity, which incorporated an adjustment to account for variation in voluntary culling based upon milk production. Lifetime performance was defined as cumulative milk production through the 6^th parity. All cows were scored for conformation traits during their first lactation. Genetic correlations between these traits and longevity measures were estimated by bivariate analysis using the DMU variance component program package. Type trait heritabilities ranged from 0.30 to 0.59, while heritabilities for longevity and functional longevity were 0.06 and 0.05, respectively. Heritability of lifetime performance was 0.08. Genetic correlations between type traits and longevity measures ranged from low to intermediate values. Genetic correlations of the measured body size traits to the real and functional longevity ranged from -0.06 to -0.29, for udder traits from -0.02 to 0.33, and for foot and leg traits from -0.03 to 0.17. Genetic correlations between the measured body size traits and lifetime performance ranged from -0.03 to -0.30, for udder traits from 0.05 to 0.47, for foot and leg traits from -0.07 to 0.15. Genetic correlations of composite trait scores for frame, muscularity, feet and legs, and udder with longevity traits ranged from -0.20 to 0.41 and for lifetime performance -0.14 to 0.51. The highest genetic correlations between a type trait and functional longevity were for composite udder score (0.25), feet and legs (0.26), and udder depth (0.33), suggesting that these traits could serve as indicators of functional longevity. We conclude that selection based upon easily and inexpensively measured type traits could improve functional longevity of cows as well as lifetime milk production.

The Weibull proportional hazards model was applied for genetic evaluation of functional longevity in Polish Simmentals. Data consisted of production and disposal records for 12 527 Simmental cows, daughters of 294 sires, calving for the first time from 1995 to 2014 in 286 herds. Length of productive life of cows was calculated as number of days from the first calving to culling or censoring. Average length of productive life of 4462 cows with complete (uncensored) survival records was 1198 days (39.3 months); mean censoring time for the remaining 8065 cows was 1093 days (35.8 months). Functional longevity was defined as length of productive life corrected for production. The model included time-independent fixed effect of age at first calving, time-dependent fixed effects of year-season, parity-stage of lactation, annual change in herd size, relative fat yield and protein yield, and random herd-year-season and sire effects. Likelihood ratio tests showed a highly significant impact of all fixed effects on longevity, except for relative fat yield. Estimated sire variance was 0.069, resulting in the equivalent (accounting for censoring level) heritability of 0.09. Standardized relative breeding values (RBV) ranged from 71 to 139 (mean 101.4, SD 9.12). Average reliability of RBVs was 0.47. Moderate heritability supports the possibility of effective selection for functional longevity, which will be included in the total selection index for Polish Simmentals.

The East Balkan pig (EBP) is a traditional domestic pig breed in Bulgaria managed in semi-wild conditions and well-adapted to the continental climate and rearing on pastures. From the genetical and historical point of view it is important to preserve this ancient breed. However, over the last several years, a dramatic decline of EBP herds has been observed. Moreover, introgression between EBP and wild boar in Bulgaria (WBB) is very likely to have occurred. In this study we used a set of 10 microsatellites and the polymerase chain reaction-restriction fragment length polymorphism method on melanocortin-1 receptor (MC1R) polymorphisms to study the degree of hybridisation between WBB, EBP, and a commercial pig breed (CPB). MC1R results identified WBB-EBP hybrids and the analysis of the microsatellite data with a Bayesian assignment approach and the Discriminant Analysis of Principal Components revealed a low genetic differentiation between WBB and EBP and a high amount of introgression of WBB into EBP. A mentionable introgression of CPB into EBP was also revealed. It is apparent that the traditional rearing system of EBP, which is hundreds of years old, has led to a permanent hybridisation between WBB and EBP. In our opinion, the preservation of the semi-wild rearing system is a prerequisite for the conservation of this old, indigenous pig breed and its genetic composition, as the semi-wild rearing system allows the continuous introgression with WBB. Moreover, the introgression of commercial breeds into EBP or WBB should be prevented. Due to the bidirectional gene flow these hybridisation events would have negative consequences (i.e. loss of viability and adaptation) for the wild boars as well as for the indigenous pig breed.

The purposes of the study were to investigate the effects of Wooden Breast (WB) myodegeneration on poultry meat quality and to give a contribution in typing lesions morphology. At a poultry meat cutting facility, 474 carcasses of a high-breast-yield hybrid chickens were inspected for WB condition, and 30 normal (N) and 30 affected (WB) breast fillets (Pectoralis major) were randomly selected. The WB condition represented 53.2% of the examined carcasses. Weight, cross sectional area (CSA), pH, L*, a*, b* colour values, water-holding capacity, and Warner-Bratzler shear force were determined. Samples were also visually and histologically evaluated. Affected samples were heavier, thicker, paler (P < 0.001), and characterized by palpatory hardness and lower water holding capacity (P < 0.05). Macroscopically, abnormalities were primarily localized in the cranial portion of the fillet and defined by the presence of bulges, petechiae, fluid and clear exudate, and higher pH. Microscopically, the WB condition was characterized by muscle fibres with greater CSA (P < 0.001) and higher giant fibres prevalence (P < 0.01). Data suggest a relationship between breast weight and WB condition.

The aim of this study was to determine the efficiency of diet-cow-calf transfer of selenium (Se) depending on the forms of Se-supplement given to cows of Simmental breed during the last trimester of pregnancy and the first week of lactation. On day 195 of pregnancy the cows were randomly assigned to one of four experimental groups (n = 6), and the newborn calves belonged to the same group as their mothers (n = 6). The cows in the control group received diet without Se-supplement, while the supplemented groups received Se in equivalent doses in a powder form (Se-unprotected) or in a protected form (Se-protected) of sodium selenite or in organic compounds (Se-yeast), the calves received colostrum and milk from their mothers. The data about feed and Se intake, colostrum and milk daily production, Se concentration in colostrum, milk, and cows and calves blood serum were recorded. The diet-cow Se transfer efficiency was estimated as the following ratios: the concentration of Se in cows' serum after parturition/daily Se intake during prepartum; Se secretion in colostrum/daily Se intake during prepartum; and Se secretion in milk at 7 days of lactation/daily Se intake. The ratios were higher (P ≤ 0.02) in the Se-yeast group than in the other supplemented groups, in the Se-unprotected and Se-protected groups the ratios were similar (P > 0.05). The cow-calf Se transfer efficiency estimated as calves' serum concentration after birth/cows' serum concentration after parturition was similar (P > 0.05) in all experimental groups. The results showed that the form of Se supplement modulated the Se transfer from the diet to cows; Se was transferred more efficiently from the Se-yeast than from sodium selenite. The form of Se supplement did not affect the cow-calf Se transfer efficiency.

Reverse transcription quantitative real-time PCR (RT-qPCR) is widely used to study the relative abundance of mRNA transcripts because of its sensitivity and reliable quantification. However, the reliability of the interpretation of expression data is influenced by several complex factors, including RNA quality, transcription activity, and PCR efficiency, among others. To avoid experimental errors arising from potential variation, the selection of appropriate reference genes to normalize gene expression is essential. In this study, 10 commonly used reference genes - ACTB, B2M, HPRT1, GAPDH, 18SrRNA, 28SrRNA, PPIA, UBE2D2, SDHA, and TBP - were selected as candidate reference genes for six fetal tissues (heart, liver, spleen, lung, kidney, and forehead skin) of yak (Bos grunniens). The transcription stability of the candidate reference genes was evaluated using geNorm, NormFinder, and BestKeeper. The results showed that the combination of TBP and ACTB provided high-quality data for further study. In contrast, the commonly used reference genes 28SrRNA, SDHA, GAPDH, and B2M should not be used for endogenous controls because of their unstable expression in this study. The reference genes that could be used in future gene expression studies in yaks were indentified.

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.

The aim of this work was to study the effect of milking fraction and mammary gland health status on the electrical conductivity (EC) of milk from Manchega ewes, considering also the lactation number. To this end, we also studied the relationship of EC with milk macrocomposition, and the relation existing between EC and somatic cell count (SCC). Finally, the use of EC thresholds as a mastitis detection method (sensitivity, specificity, positive (PPV) and negative predictive value (NPV)) was assessed in each of the three fractions: first streams (F1), machine milk (F2) and stripping milk (F3). Milking fraction, mammary gland health status and lactation number had a significant effect on EC and SCC. In the case of EC, the milking fraction caused a more pronounced effect than health status of the glands or number of lactation (F = 19.95, 15.88 and 6.55, respectively; P < 0.5). In SCC, the gland health status caused the most pronounced effect followed by milking fraction and lactation number (F = 112.02, 6.89, and 5.28, respectively; P < 0.05). Changes in the milk composition, especially fat and lactose contents, explained the EC variation to a great extent. For the same EC threshold, specificity and sensitivity varied slightly depending on the milking fraction. NPV above 80% was obtained in the three milking fractions and at all EC thresholds tested, but PPV was only higher than 20% as of the threshold of 4.5, 4.4, and 4.2 mS/cm in F1, F2 and F3, respectively. From the results obtained, we concluded that the algorithm design for mastitis detection in sheep should include those factors affecting the composition and which therefore cause variations in EC, such as milking fraction, individual differences, lactation stage or lactation number.

The purpose of this research was to find a suitable protocol to enhance frozen rabbit sperm preservation analysing the role that seminal plasma (SP) plays and the effect of different cryoprotectant agents on sperm quality 0 and 2 h after thawing. Sperm samples were pooled and divided in eight fractions. Four of them were diluted with BotuCrio^® (extender A), INRA 96^® plus 6% glycerol (extender B), 6% N, N-dimethylformamide (extender C) and 6% N-methyl-2-pyrrolidone (extender D), respectively. The other four fractions were centrifuged and the supernatant was discarded in order to eliminate SP. Each sample was then resuspended with extender A, B, C and D. Samples were cooled progressively, loaded into 0.5 ml freezing straws and frozen with liquid nitrogen vapour. Thawing was performed by placing the straws into a bain-marie at 37°C for 21 s. Straws were dried and sperm samples placed into Eppendorf tubes to be analyzed by ISAS software, vitality test, HOS test and acrosome integrity test. The best motility and velocity parameters were obtained by extender A (P < 0.050) even when the motility parameter was compared with previous studies using other diluents. Additionally, sperm quality decreased over incubation time (P < 0.050) and no differences were found in samples processed with or without SP. This research revealed that BotuCrio^® could be used for rabbit sperm cryopreservation and moreover the improvement of the cryopreservation process of rabbit sperm due to the demonstration that SP removing is not required.