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

Major genes could be introgressed into laying hens to attenuate heat stress. However, under cold and/or moderate ambient temperature, these genes might possess different behaviour. The main objective of this study was to evaluate laying performance, immune response, and antioxidant status of native laying hens segregating for naked neck (Na) and frizzle (F) genes under low ambient temperature. Five genotypes were studied: homozygous naked neck (NaNaff), heterozygous naked neck (Nanaff), homozygous frizzle (nanaFF), heterozygous frizzle (nanaFf), and normally feathered (nanaff). The hens were raised under temperature range 22.2-16.7°C. No adverse effect due to ambient temperature was detected in laying performance for naked neck genotypes. Significant decrease in egg weight was recorded in nanaFF genotype compared to the other genotypes leading to significant decrease in egg mass. Significant improvement in shell thickness was associated with Na and F genes. NaNaff genotype had a significantly higher eggshell strength compared to nanaff. Furthermore, Na and F genes improved cellular mediated immune responsiveness, whereas this improvement did not extend to humoral immunity. Birds carrying F gene in homozygous state had a higher total antioxidant activity compared to the remaining genotypes. It could be concluded that the presence of Na and F genes in laying hens raised under low ambient temperature significantly increased shell thickness and, in turn, improved shell strength. Moreover, they greatly enhanced cellular immunity, particularly in heterozygous naked neck status.

The present study aimed to evaluate the effect of two dietary Ca levels (3.00% vs 3.50%) in three hen genotypes (ISA Brown, Bovans Brown and Moravia BSL) on their laying performance and quality of their eggs. In order to evaluate the response to dietary Ca, an experiment was conducted with 300 laying hens. One hundred birds from each genotype were divided into 10 replicates (10 birds/cage/Ca level). To reveal the differences, the following characteristics were measured: hen-day egg production percentage, daily feed intake, egg weight, albumen and yolk weights, Haugh unit, eggshell colour, eggshell weight, eggshell thickness, eggshell strength, egg shape index and eggshell index. A higher Ca level significantly increased the hen-day egg production percentage of Bovans Brown and Moravia BSL, while ISA Brown laying hens had the higher egg production percentage at a lower dietary Ca level (85.97% vs 82.41%). No significant effect of dietary Ca level was observed on any internal egg quality measurements except the Haugh unit. However, the dietary Ca level significantly affected some of external egg quality measurements, namely eggshell colour (P < 0.001), eggshell weight (P = 0.003) and eggshell strength (P = 0.012). The results of the present study show that laying performance and egg quality parameters responded differently according to hen genotype and dietary Ca level. Bovans Brown and Moravia BSL laying hens required higher levels of Ca to keep egg production high, while the eggshell quality measurements were better at the lower dietary Ca level. Thus, it is recommended to adjust the Ca levels in feed to the nutritional requirements of laying hens.

The influence of inbreeding depression on phenotypic traits of the Lizard canary from an Italian breeder was evaluated. The following traits were studied: birds' life span, number of surviving offspring, and morphological traits (type of plumage, spangles, feather quality, breast, cap, ground colour, wings and tail, eyelashes, covert feathers, beak, legs and feet, habits, and size). The effects of inbreeding on genetic diseases and on the health of the breed were also considered. The inbreeding coefficient of each bird was computed by genealogical data. The distribution of inbreeding in the whole population was analyzed and eleven different inbreeding level classes were considered. Birds were also divided into healthy and unhealthy animals (animals with genetic abnormalities such as blindness, splay legs and cataracts, or genetic predispositions, such as feather cysts (lumps), or animals with slow growth and/or a slender structure). Despite the high levels of inbreeding in the population, the results showed that 80.47% of the birds were healthy and no significant differences were observed between healthy and unhealthy animals in terms of the degree of inbreeding. Evidence of inbreeding depression was observed in the number of surviving offspring and the life span, whereas phenotypic characters did not show any evidence of inbreeding depression.

When analyzing phenotypes undergoing a complex mode of inheritance, it is of great interest to switch the scope from single genes to gene pathways, which form better defined functional units. We used gene networks to search for physiological processes and underlying genes responsible for complex traits recorded in dairy cattle. Major problems addressed included loss of information from multiple single nucleotide polymorphisms (SNPs) located within or close to the same gene, ignoring information on linkage disequilibrium and validation of the obtained gene network. 2601 bulls genotyped by the Illumina BovineSNP50 BeadChip were used. SNP effects were estimated using a mixed model, then underlying gene effects were estimated and tested for significance, subsequently a gene network was constructed and the functional information represented by the network was retrieved. The networks were validated by repeating the above-mentioned analyses after permutation of bulls' pseudophenotypes. Effects of 4345 genes were estimated, what makes 16.4% of all genes mapped to the UMD3.1 reference genome. Assuming the maximum 10% type I error rate, for milk yield 50 different gene ontology (GO) terms and three pathways defined by the Kyoto Encyclopedia of Genes and Genomes (KEGG) were significantly overrepresented in the real data as compared to the permuted data sets, while for fat yield nine of the GO terms were significantly overrepresented in the real data network, although none of the KEGG pathways reached the significance level. In turn, for protein yield 28 of the GO terms and six KEGG pathways were significantly overrepresented in the real data. Based on the physiological information we identified sets of loci involved in the determination of milk yield (224 genes), fat yield (72 genes), and protein yield (546 genes). Among the genes some have large effects and have already been reported in previous studies, whereas some others represent novel discoveries and thus most probably genes with medium or small effects on trait variation.

The objective of this study was to find genetic relationships between lactation persistency and conformation traits of Polish Holstein-Friesian cows. The data were derived from SYMLEK - the Polish National Database. The analysis used 22 conformation traits and 3 persistency measures of 18 216 first lactation cows. Persistency was defined as milk yield in the second 100 days in milk (DIM) divided by the yield in the first 100 DIM, milk yield in the third 100 DIM divided by the yield in the first 100 DIM, and milk yield at 280 DIM divided by milk yield at 60 DIM. The lactation curve was modelled with fourth-order Legendre polynomials using a multiple-trait prediction method. The multiple-trait REML method was applied for (co)variance component estimation. The linear model for persistency included fixed effects of herd-year-season of calving, age of calving class, and random animal effect; the linear model for type traits included fixed effects of herd-year-season of calving-classifier, age of calving class, lactation stage, and random animal effect. Stature and composite type traits (except type and conformation) were moderately or strongly genetically correlated with each of the three persistency measures. Genetic correlations of lactation persistency with overall feet and leg score and overall udder score were height and positive, whereas the correlations with stature and size were height but negative. All linearly scored traits had little genetic relationship with persistency measures except for rear udder height, udder width, and foot angle. In these three cases the genetic correlations with persistency measures were relatively high, positive, and preferable. The obtained genetic correlations suggest that increased weights of composite traits like size, overall feet and leg score, and overall udder score in the selection index, as well as selection for better rear udder height and foot angle, might cause a favourable correlated response in persistency.

The Old Kladruber horse is an important Czech genetic resource. In the current study, two categories of traits were evaluated - the first, a numerical score for Type and Gender Expression and the second, 11 traits describing performance divided into four categories: (1) Rideability (Overall Impression, Rideability), (2) Gaits (Walk, Trot, Canter), (3) Carriage Drivability (Dressage Test, Obstacle Driving Test, Marathon Test), and (4) Reliability in Tug (First Tug, Second Tug, Third Tug). The original data set contained records from 700 individuals from the period 1995-2014, each horse having 3-5 performance evaluations for the suite of traits. Our objective was to identify a suitable model for the estimation of genetic parameters and prediction of breeding values. Only one model was examined for the Type and Gender Expression trait, whereas three models were compared for the analysis of each performance trait. Criteria for choosing the most appropriate model were minimal values for the deviance information criterion (DIC) statistics, low ratios of residual variance to phenotypic variance, and maximal heritability estimates. The heritability estimate for Type and Gender Expression was 0.18. For the performance traits, the model with the fewest sources of variation (model 1) was more appropriate than two alternatives with more sources of variation. Heritability estimates from this model ranged from 0.08 to 0.40, while estimates for various performance traits from the other models were in the range 0.08-0.24. Low heritabilities for several of the performance traits suggested that selection for their genetic improvement would likely be unsuccessful. In order to maintain genetic variability, inbreeding, and fitness in the Old Kladruber population we suggest to use breeding value estimation using the heritabilities and the method presented in this paper.

Toxicity is a major limitation to successful spermatozoa cryopreservation of fish. Due to this problem, it is critical to find potential cryoprotectants which are more environmental-friendly, non-toxic, easily prepared, and available at affordable prices. Hence, the objective of the present study was to investigate several natural cryoprotectants for optimal cryopreservation of the African catfish, Clarias gariepinus, Burchell 1822 (Pisces: Clariidae) spermatozoa. Three natural cryoprotectants were tested - egg yolk, glucose, and honey, while DMSO was used as a control at different concentrations (5, 10, and 15%). Sperms were diluted with coconut water at a dilution level of 1 : 20 sperm to extender (v/v). Diluted sperms were kept at 4°C for 5 min, then at 0, -4, and -79°C for 5 min respectively, and stored in liquid nitrogen (-196°C) for 45 days. The cryopreserved sperms were thawed in a water bath (37°C) for 5 min and evaluated for fertilization and hatching rates. The data were subjected to analysis of variance (ANOVA), followed by comparison of means using Duncan's Multiple Range Test. The fertilization and hatching rates of African catfish in all cryoprotectants improved with concentration increasing from 5 to 10% but then decreased when concentration was increased to 15%. The ANOVA test showed that the differences in cryoprotectants used significantly affected fertilization and hatching rates of African catfish. Overall, the fertilization and hatching rates were higher in DMSO for all concentrations compared to other cryoprotectants. However, 10% egg yolk resulted in higher fertilization and hatching rates compared to other natural cryoprotectants. It was concluded that 10% egg yolk was the most suitable concentration for African catfish spermatozoa cryopreservation compared to other natural cryoprotectants tested.

The microRNAs are non-coding RNA molecules of approximately 20-22 nucleotides that are found to be implicated in a wide range of physiological processes. In this study, the suitability of 10 candidate reference RNAs was evaluated for microRNA expression data in the skin tissue of Liaoning cashmere goat including 1 small nuclear RNA (snRNA; RNU6B), 1 small nucleolar RNA (snoRNA; Z30), 1 rRNA (5S), 1 transfer RNA (tRNA; Met-tRNA), and 6 microRNAs (miR; let-7d-5p, miR-15a-5p, miR-26a-5p, miR-125a-5p, miR-214-3p, and miR-221-3p). Based on geNorm and NormFinder algorithms, we identified let-7d-5p, miR-26a-5p, and miR-15a-5p as the most stable reference RNAs. Also, three reference RNAs (let-7d-5p, miR-26a-5p, and miR-15a-5p) were sufficient for the normalization of microRNA expression data in the skin of this breed. We further assessed the suitability of let-7d-5p, miR-26a-5p, and miR-15a-5p in a combination as reference RNAs through detecting the relative expression of miR-24-3p, miR-29a-3p, miR-145a-5p, and miR-205-5p as putative genes of interest. Significant differences were revealed in the relative expression of miR-24-3p, miR-29a-3p, miR-145a-5p, and miR-205-5p at telogen stage of hair follicle cycle when a combination of let-7d-5p, miR-26a-5p, and miR-15a-5p vs a single let-7d-5p were used as reference RNA. Based on the results from this study, we suggested that the combination of let-7d-5p, miR-26a-5p, and miR-15a-5p as normalizers for microRNA expression data would be more reliable than that of single let-7d-5p, and the geometric mean of these three microRNAs (let-7d-5p, miR-26a-5p, and miR-15a-5p) can be used for the normalization of microRNAs expression data in the skin of Liaoning cashmere goat.

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

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.

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

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

Growth curves of the Morada Nova sheep males and females were described using nonlinear models and the relationships between body weight and thoracic circumference were evaluated. Altogether 1516 repeated measures of body weight and thoracic circumference of the Morada Nova sheep (668 males and 848 females) taken since birth till 730 days of age were used. The Brody, Richards, von Bertalanffy, Gompertz, and Logistic models have been tested. The Fisher's test (F) was used to verify the differences (P < 0.05) in growth curves between males and females. The Gompertz model presented a significant difference (P < 0.001) for growth curve parameters between males (asymptotic weight (A) = 40.5 kg and maturing rate (k) = 0.0043 kg/day) and females (A = 36.44 kg and k = 0.0028 kg/day). The relationships between body weight and thoracic circumference presented R² above 0.7 and a high significance (P < 0.0001) for all categories, showing that the thoracic circumference may be a good indicator of body weight. In addition, a significant effect (P < 0.05) of the relationship between thoracic circumference and prediction of animal's body weight was verified using the models of linear, quadratic, and cubic regression. Among the models studied, the Gompertz model presented the best fit and biological interpretation. Furthermore, the Gompertz model indicated the need to separate animals by sex in order to properly meet nutritional requirements and determine adequate slaughter age. Thoracic circumference can be used to predict animal body weight with a high accuracy.

Statistical methods of imputation allow predicting genotypes of markers (which were not genotyped in the whole population) based on known linkage disequilibrium relationships between the flanking polymorphisms and the information obtained from reference datasets used as a pattern. In this study we attempted to predict genotypes of two bovine spongiform encephalopathy (BSE) susceptibility associated indel polymorphisms located in the promoter region of PRNP gene relying on the data obtained from middle density SNPs arrays in a sample of the population of Holstein cattle. The two SNPs panels spanning PRNP locus were tested in terms of imputation efficiency. Both panels gave satisfactory imputation results showing high accuracy and high probabilities of imputed genotypes. Our results suggest that the approach applied can be used to evaluate the frequency of the disease associated polymorphisms in large populations of animals genotyped with whole-genome SNPs panels based on a limited-size reference population and small financial outlays.

The objective of the present study was to estimate genetic parameters and predict breeding values of sport horses in the Czech Republic using animal model variations. The data set for the evaluation was composed of edited records of show jumping competitions in the Czech Republic in years 1991-2013. Input data were not normally distributed; hence Blom transformation was used for the variable filtration. The Gibbs sampling algorithm was used for the genetic parameters estimation. Two models were examined. The first was a random regression model including the effect of a horse's experience in competition (expressed as the length of the horse's sporting career in days), fixed effects of sex, age, and event, and random effects of rider, permanent environment, and animal. The second model was a multi-trait model with fixed effects for sex, age, and event and random effects for rider, permanent environment, and animal. In this latter case, horse performance was classified as three traits. The first trait was jumping results from obstacle heights of 90-110 cm, the second of 120-135 cm, and the third of 140-155 cm. In the random regression model, heritability estimates ranged from 0.01 to 0.11; whereas in the multi-trait model, heritabilities were 0.07, 0.11, and 0.14 for the first, second, and third trait, respectively. Results indicate that both models could be used to predict breeding values of sport horses in the Czech Republic. The multi-trait model revealed that heritability estimates increased with the increasing height of obstacle. In the random regression model, breeding values differed according to a horse's experience in competition, allowing adjustment of the breeding value for the environmental effect of a past experience.

The CD9 cell surface molecule has been found to be important for the fertilization process of mammals. The aim of this study was to investigate, whether the molecule CD9 is expressed on bull sperm during the spermatogenesis and maturation of spermatozoa as well as in bull reproductive organs and their secreta. The expression of bovine CD9 was examined by immunohistochemistry, immunofluorescence, and immunoblotting. The histochemical studies using an anti-CD9 monoclonal antibody showed strong staining in the myeloid and collagenous tissue layer of testis and epididymis. Strong reaction was observed in the lumen of epididymal duct (the fluid of the duct) but the clumped spermatozoa in the lumen of the duct remained unstained. Intensive tissue staining was observed in the range of epithelial microvilli of epididymis (body and tail) and in the fluid content of tubules. The Western blot analysis showed the 24kDa molecule in sperm protein extracts of ejaculated sperm and also in the protein extracts of the sperm obtained from the head, body, and tail of epididymis but the localization of CD9 on the sperm was not directly confirmed. However, the obtained data could be considered in the interpretation of the role of CD9 in spermatogenesis and sperm-oocyte interactions.

The objective of this study was to evaluate the usefulness of young bulls' conformation scores in a national type evaluation system. For this purpose the genetic correlations between conformation traits of sires and the same type traits of their daughters were estimated. Young bulls were evaluated as required for registration in the herd book and for entering progeny testing. Data were 7 linearly scored (1-9 scale) and 3 descriptive (scored from 50 to 100) conformation traits of 933 young bulls born between 2005 and 2008, and the same traits evaluated in their 65 479 daughters. A two-trait animal model was used to estimate genetic correlations between the type traits of bulls and their daughters. (Co)variance components were estimated by a Bayesian method via Gibbs sampling. Two linear models were used: the linear model for bulls included fixed linear regressions on age at evaluation, fixed effects of herd and classifier, and random additive genetic effect; the linear model for cows contained fixed effects of herd-year-season-classifier, lactation stage, fixed linear regression on age at calving, and random additive genetic effect. Estimates of bulls' heritabilities for all analyzed traits ranged from 0.07 for feet and legs to 0.25 for body depth. Heritabilities of cows were the lowest for rear legs rear view (0.05) and foot angle (0.06), and the highest for size (0.43). The genetic correlations between similarly described traits of bulls and their daughters were moderate to high (0.42-0.91). The lowest genetic correlation (0.42) was for chest width, and the highest (0.91) for rump angle. The magnitude of genetic correlations between pairs of type traits of sires and daughters was high enough to suggest that the body conformation of dairy cows can be improved by making use of some measurements taken from young bulls. Including highly correlated bull scores for size, rump angle, and three linear leg traits in the evaluation system could improve the accuracy of type breeding value evaluation.

The relationship between growth and development of body condition during the rearing of replacement heifers and their subsequent performance in the production period of Holstein cows in the Czech Republic was studied. The data set used in this study covered 733 Holstein heifers born on one farm during the years 2004-2009. The evaluated effects considered were body weight (BW), average daily gain of live weight (ADG), and body condition score (BCS) of heifers. The results demonstrated the desirable effect of the higher achieved ADG in the period before sexual maturity on the lower age at first calving (AFC), the positive influence on milk yield in the first lactation, and the negative relationship to the conception rate of heifers before first calving. Similar effects were also found for growth in the period of 9-12 months of age. In heifers with a greater growth rate before puberty there was not a significant risk of excessive BCS during the breeding period. Heifers with the highest BCS (3.5 points (p.) and more) at 14 months of age had significantly the lowest milk yield in the first and second lactation compared to heifers with medium (3.5 p.) and low (3.25 p. or less) BCS. Over-conditioned heifers exhibited higher milk protein content in the first and second lactation. No effects on the third lactation were observed.

Genetic parameters for basic and composite reproductive traits in Mehraban sheep were estimated. Data included 10 257 records on reproductive performances of 5813 lambs from 69 sires and 603 dams which were collected from 1994 to 2011 in the Mehraban breeding station in Hamedan province, western Iran. Studied traits were litter size at birth (LSB), litter size at weaning (LSW), litter mean weight per lamb born (LMWLB), litter mean weight per lamb weaned (LMWLW), total litter weight at birth (TLWB), and total litter weight at weaning (TLWW). Test of significance to include fixed effects in the statistical model was performed using the GLM procedure of SAS. Genetic parameters were estimated with univariate and bivariate repeatability animal models using WOMBAT program. Direct heritability estimates were 0.16, 0.14, 0.03, 0.16, 0.06, and 0.18 for LSB, LSW, LMWLB, LMWLW, TLWB, and TLWW, respectively, and corresponding repeatabilities were 0.02, 0.01, 0.73, 0.41, 0.27, and 0.03. The estimate for animal-dependent permanent environmental variance ranged from 0.01 ± 0.04 for LMWLW to 0.23 ± 0.04 for LSB. Genetic correlation estimates between traits ranged from -0.98 for LSB-LMWLW to 0.99 for LSB-TLWB. Phenotypic and environmental correlations were generally lower than genetic correlations. Phenotypic correlations ranged from -0.50 for LSB-LMWLB to 0.85 for LMWLW-TLWW. Environmental correlations ranged from -0.45 for LSB-LMWLB to 0.87 for LMWLW-TLWW. The results suggested that indirect selection based on TLWW could improve the reproductive performance in Mehraban ewes more effectively than if based on the other traits.

The Bulgarian Grey Cattle (BGC) and Shorthorn Rhodopean Cattle (SRC) are indigenous breeds from the Balkan Peninsula region. The Balkans, as part of Southeast Europe, is a crucial civilization crossroad of cultures, people, and livestock. This region is considered the civilization "cradle" of prehistoric times (around 6500 BC). The aim of the present study is to reveal the genetic profile and population structure of BGC and SRC according to displacement loop control region. The results showed that these ancient cattle breeds belong to the common T1, T2, and T3 haplogroups. Within the BGC population the T3a sub-haplogroup was predominant (about 80% - 31/39) with haplotypes BGC-4.1 (33% - 13/39) and BGC-4.2 (about 40% - 16/39). Mitochondrial DNA analysis of SRC population showed a heterogeneous structure consisting of five basic haplo- and sub-haplogroups, all based on twelve haplotypes with equal frequencies. Based on 173G polymorphic site newly named sub-haplogroup T3c was proposed. A detailed comparative analysis with other Balkan cattle populations was performed. Data showed multiple haplotype mtDNA profile with no phylogenetic relationships within.

This study describes the results of molecular screening in the Agerolese cattle breed from southern Italy, which constitutes an economical source and contributes to the regional biodiversity. Integrated electrophoretic, chromatographic, mass spectrometric, and DNA sequencing procedures were used to qualitatively and quantitatively evaluate globin chain polymorphism in a population of animals from different farms. In addition to α-, β^A-, and β^B-globin-bearing animal phenotypes, our data demonstrate the occurrence of individuals characterized by the presence of a novel α-globin variant, whose primary structure differs from the normal counterpart for the p.Ala27Thr substitution. The SNP c.79G>A located at the exon 1 of the HBA2 gene is responsible for this amino acid change and it represents a third example of α-globin gene polymorphism observed in Bos taurus. This phenomenon was ascertained only in two Mediterranean breeds from southern Italy and highlights the uncommon occurrence of α-globin variants in this geographical region, similarly to what has already been described in goat and human.

The Trivers-Willard hypothesis (TWH) predicts the ability of mothers to adaptively adjust offspring sex ratio through differential maternal investment based on their relative body condition. In the present study we have analyzed an extensive data set on the secondary sex ratio (SSR) including 59 335 goat kids born in 30 633 litters to 11 644 mothers on farms all over the Czech Republic during the years 1992-2004. We found a male-biased SSR 0.568, which significantly deviates from the predicted balanced Fisherian equilibrium 1 : 1 (P < 0.0001). A generalized estimating equation model controlled for mother's identity revealed a significant effect of maternal age and season of conception (P < 0.001). Conversely, neither paternal age, gestation length, nor litter size were found to explain the sex ratio variation. We also failed to prove any effect of variables associated with maternal condition, particularly her body weight, breed, arbitrary ranking of genetic quality, and hornedness that were available in a data subset. Thus, unlike in some other ungulate species, our findings do not support the TWH in the domestic goat despite the tendency for male-biased litters and we discuss some alternative adaptive and proximate mechanism of the mammalian SSR.

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.

The objective of this study was to evaluate the effects of bacterial and chemical additives on the number of lactic acid bacteria (LAB) and on fermentation indicators in whole maize silage at 1, 3, 5, 10, and 90 days of fermentation. Maize forage was harvested at approximately 34% dry matter (DM) and treated with (1) no additive (control; C); (2) bacterial inoculant (2 g/t of forage; B) containing the homofermentative LAB Lactobacillus plantarum, Lactobacillus paracasei, and Pediococcus pentosaceus (1.5 × 10¹¹ cfu/g of inoculant); and (3) chemical additive (4 l/t of forage; CH) containing formic acid, propionic acid, ammonium formate, and benzoic acid. Both treatments decreased pH of silage at day 1 of ensiling (P < 0.05), and the lowest value of 4.34 was observed in the CH-treated silage. All silages were well fermented and had pH < 4.0 by day 10 of fermentation. The concentration of lactic acid and the lactic acid : acetic acid ratio increased over time in all treatment groups, and the highest values were 87.5 and 3.62 g/kg of DM, respectively, observed for group B at day 90 (P < 0.05). The concentrations of water-soluble carbohydrates were higher (P < 0.05) for CH compared to C and B at days 3, 5, 10, and 90 of fermentation. The CH silage had fewer LAB (P < 0.05) than did either C or B silages regardless of the days of fermentation. Both additives used in the present study improved fermentation dynamics of the whole crop maize silage.

The differences in egg production traits in six laying hen genotypes (brown-egg hens Bovans Brown, Bovans Sperwer, ISA Sussex; white-egg hen Dekalb White; laying hens with tinted shells Moravia Barred and Moravia BSL) and the interactions of genotype and oviposition on egg quality were evaluated. The genotype affected the laying rate (P ≤ 0.003), mean sequence length (P ≤ 0.001), and time of oviposition (P ≤ 0.001). The brown-egg genotypes laid eggs approximately 1 h earlier than the white-egg genotypes and approximately 2 h earlier than the tinted-egg genotypes. Egg shell strength was the lowest in tinted-egg genotypes (P ≤ 0.001) and declined with the time of oviposition (P ≤ 0.002). Egg shell percentage (P ≤ 0.011) and thickness (P ≤ 0.011) were affected by the interaction of genotype and oviposition. None of the effects affected egg weight; however, the proportion of egg components was significantly influenced by the interaction of genotype and oviposition. The study confirmed that the differences in the egg production and egg quality of various genotypes are associated with the laying pattern.

Objectives of the study were to examine alternative measures of growth potential of bulls in testing stations, determine whether genetic parameter estimates of such traits changed over time, and examine whether existing methods for performance testing were appropriate. Records from 1980 to 2010 of 44 425 Fleckvieh bulls in Czech progeny testing stations were analyzed. The following traits were examined: weight at the beginning of the test (150^th day of age), weight at the end of the test (530^th day of age), gain from birth to the beginning of the test, and gain during the test. Fixed effects in five multi-trait animal models were station-year-season groups, linear and quadratic regressions on age, and regression on heterozygosity (proportion of an individual's loci with alleles from different ancestor breeds). Random effects included additive genetic, permanent environment, and residual variances. Separate analyses were conducted in four consecutive time periods (1980-1987, 1988-1992, 1993-1997, and 1998-2010). Across these time intervals, estimates of additive genetic variance decreased for all of the traits, while estimates of residual variances increased. In consequence, heritability estimates for all of the traits decreased over time. This decrease was most apparent for gain during the test, for which heritability declined by more than 50% over the course of the study. Results demonstrate that over three decades, the system of testing came into conflict with genetic improvement of the breed, possibly because the measured traits changed genetically over the course of selection. Regular analysis of the recorded data, re-estimation of genetic parameters in relation to time, and appropriate modification of existing methods of rearing/fattening in station tests are required. When such inspections are neglected, data from the testing stations may not accurately reflect genetic merit of individual animals.

Genetic correlations between longevity and conformation traits were estimated using data on Czech Holstein cows first calved in the years 1993-2008. Longevity traits considered were length of productive life and number of lactations initiated and their functional equivalents (i.e. the longevity traits corrected for milk production). Conformation traits were twenty one linear descriptive type traits, six composite traits and height at sacrum measured in cm. A possible nonlinear relationship between conformation and longevity traits was also investigated. The heritabilities ranged from 0.05 to 0.43 for conformation traits and from 0.03 to 0.05 for longevity traits. Low to moderate genetic relationships between conformation and longevity traits were found. The genetic correlations were higher for functional longevity than for direct longevity traits. Negative genetic correlations with all longevity traits were found for height at the sacrum, stature, dairy form, body conformation, and capacity. Final score showed weak genetic correlation with all analyzed longevity traits. Positive genetic correlations occurred between feet and legs and direct longevity and functional longevity (0.19, 0.14) and between udder and direct longevity (0.10). Body condition score and angularity showed strong genetic correlations with functional longevity (body condition score 0.30, angularity -0.31). Foot and leg traits showed weak genetic correlations with longevity traits except rear legs set (side view) (-0.24) and hock quality (0.19). The udder traits showed inconsistent and rather weak genetic correlations with longevity traits, with the exception of a stronger genetic correlation between rear udder width and functional longevity (-0.22) and between central ligament and number of lactations (-0.18, -0.19). The teat traits showed always negative genetic correlations with longevity traits. The strongest correlations were found for rear teat position (-0.28) and the weakest for teat length (-0.03). Some conformation traits showed markedly stronger genetic correlations with functional longevity than with direct longevity (rear udder width and rear udder height, dairy form, body condition score, angularity, rear legs set (side view), rear legs rear view). A quadratic relationship between conformation and longevity traits did exist. Even if the linear relationship generally prevailed, the quadratic relationship should be taken into account.

The objective of this study was to determine whether nutrient digestibility and growth performance of mink were affected by different dietary copper levels. Ninety-six 60-day-old healthy female minks were randomly assigned to 8 treatment groups with 12 animals in each group and fed a diet supplemented with either 0, 4, 8, 16, 32, 64, 128 or 256 mg/kg copper as CuSO₄ × 5H₂O, respectively. Our data showed that body weight and average daily gain increased (linear and quadratic, P < 0.05) as Cu increased in the diet, the highest body weight and average daily gain were seen in the Cu32 group. Feed : gain ratio responded in a linear (P = 0.0025) fashion with increasing level of Cu, the lowest feed : gain ratio was seen in the Cu64 group. Digestibility of ether extract responded in a linear (P = 0.0190) fashion with increasing level of Cu. There were no differences in apparent digestibility of dry matter, CP, and gross energy among groups (P > 0.05). N retention linearly (P = 0.0363) responded to increasing levels of Cu. Glutamic-oxalacetic transaminase and glutamic-pyruvic transaminase increased (linear and quadratic, P < 0.05) as Cu increased in the diet; the highest glutamic-oxalacetic transaminase and glutamic-pyruvic transaminase were seen in the Cu256 group. Total protein of the minks was similar among the treatments, however, albumin in serum responded in a linear (P = 0.0370) and quadratic (P = 0.0049) fashion with increasing level of Cu. The activity of ceruloplasmin responded in a linear (P = 0.0001) and quadratic (P = 0.0203) fashion with increasing level of Cu. The activity of Cu-Zn superoxide dismutase responded in a linear (P = 0.0010) fashion with increasing level of Cu. Our results indicate that supplemental Cu plays an important role in the growth performance of mink, helping young female mink digest and efficiently utilize added dietary fat.

The objective of the present study was to examine if luteal blood flow (LBF) monitoring could be used as an additional prognostic tool for early pregnancy diagnosis, and we particularly focused on the differences in LBF between pregnant and nonpregnant mares. Furthermore, other possible developmental differences of corpus luteum (CL) between pregnant and nonpregnant mares were evaluated. The CL (n = 119) of 27 mares were monitored once daily in B- and Power-Doppler Mode on days 1, 2, 9, 12, and 16 after ovulation (day 0 = ovulation). The data were evaluated using the MIXED Linear Model with repeated measures, and parameters were estimated by the REML method. The course of LBF, area of CL, and pixel intensity differed in nonpregnant mares on a day-to-day basis in contrast to more stable values in pregnant mares. Further, the profiles of the courses were identical until day 9, but since day 12 the differences between pregnant and nonpregnant mares started to be prominent. The LBF, pixel intensity, and level of progesterone (P4) were similar in all mares until day 16, when smaller LBF, lower pixel intensity, and lower levels of P4 were found in nonpregnant mares (P = 0.04, P = 0.02, P < 0.05, respectively). In pregnant and nonpregnant mares the LBF was weakly (r = 0.29 in both) and pixel intensity strongly (r = 0.48 and 0.59, respectively) correlated to the levels of P4. LBF was strongly correlated to the area of CL in pregnant as well as nonpregnant mares (r = 0.72 and 0.64, respectively). In accordance with the results presented in our study we can state that LBF monitoring is not a suitable tool for early pregnancy diagnosis or prognosis as the differences between pregnant and nonpregnant mares are notable - similarly to other indicators of CL status - just after the onset of luteolysis (day 16) when embryo itself is detectable.