Performance Testing Station Research Articles

Novel interpretation of sperm stress test and morphology for maturity assessment of young Norwegian Red bulls

The use of genomic selection significantly reduces the age of dairy bulls entering semen production compared to progeny testing. The study aimed to identify early indicators that could be used for screening bulls during their performance testing period and could give us insight into their future semen production performance, acceptance for the AI station, and prediction of their future fertility. The study population consisted of 142 young Norwegian Red bulls enrolled at the performance test station, followed until we received semen production data, semen doses, and, subsequently, non-return rates (NR56) from the AI station. A range of semen quality parameters were measured with computer-assisted sperm analysis and flow cytometry from ejaculates collected from 65 bulls (9–13 months). The population morphometry of normal spermatozoa was examined, showing that Norwegian Red bulls at 10 months of age have homogenous sperm morphometry. Norwegian Red bulls could be separated into 3 clusters according to their sperm's reaction patterns to stress test and cryopreservation. Results of semi-automated morphology assessment of young Norwegian Red bulls showed that 42% of bulls rejected for the AI station and 18% of bulls accepted had ejaculates with abnormal morphology scores. For the youngest age group at 10 months, the mean (SD) proportion of spermatozoa with normal morphology was 77.5% (10.6). Using novel interpretation of sperm stress test combined with sperm morphology analysis and consecutive cryopreservation at a young age allowed identification of the candidate's sperm quality status. This could help breeding companies introduce young bulls earlier to the AI stations.

Associations between insulin-like factor 3, scrotal circumference and semen characteristics in young Norwegian Red bulls.

With the integration of genomic selection in the cattle artificial insemination (AI) industry, bulls are selected for their semen production capacity and fertility at a younger age than previously. Norwegian Red bull calves selected as candidates to become future AI bulls based on their genomic breeding value are kept in a performance testing station from around the age of 3-12months, allowing for sample collection and analysis of different parameters during their pre- and peripubertal period. Insulin-like factor 3 (INSL3) is a small peptide hormone specifically secreted by the mature Leydig cells of the testes. In the foetus, it induces the first phase of testicular descent and is considered to reflect Leydig cell development during puberty; it could therefore be an interesting early indicator of future semen production capacity. The main objective of our study was to evaluate the relationship between INSL3, scrotal circumference (SC), and semen characteristics. This is the first time INSL3 was measured in the Norwegian Red population. We collected blood samples for analysis of INSL3 from 142 Norwegian Red bulls at the performance testing station and measured their SC on the same day. Altogether, measurements were made at four time points: upon arrival at the performance testing station (quarantine (Q): 2-5months) and later at approximately 6, 9 and 12months of age. Information on season and place of birth were made available from the database of the breeding company Geno, together with data on semen characteristics from the test station and the AI station. The median SCs for age groups Q, 6, 9, and 12 were 15, 21.5, 29, and 34cm, respectively. INSL3 was shown to be positively correlated with SC (R = 0.4) but not with any of the semen characteristics. Similarly, we found no correlation between SC and sperm characteristics from data on ejaculates analysed at the performance testing station and AI station. The mean sperm volume for the 31 selected bulls with at least 10 ejaculates produced in the AI station increased from 2.3ml at the performance testing station to 6.4ml at the AI station. The corresponding increase in mean sperm concentration was from 497 million/ml to 1049 million/ml. We conclude that INSL3 exhibits high inter-individual variability in the Norwegian Red bull population, which cannot be explained by the parameters measured in this study. At present, INSL3 cannot be used as a biomarker of sperm production in this breed.

Genetic analysis of semen characteristic traits in Norwegian Red bulls at the artificial insemination center

Compared with cow fertility, genetic analyses of bull fertility are limited and based on relatively few animals. The aim of the present study was to estimate genetic parameters for semen characteristics of Norwegian Red bulls at the artificial insemination (AI) center (Geno AI station, Stange, Norway) and to estimate genetic correlations between some of these traits and andrology traits measured at the performance test station. The data from the AI center consisted of records from 137,919 semen collections from 3,145 bulls with information on semen weight, sperm concentration, motility before and after cryopreservation, motility change during cryopreservation, and number of accepted straws made. Data from the performance test station included 12,522 observations from 3,219 bulls on semen volume, concentration, and motility (%) when fresh and after storing for 24 and 48 h. Genetic parameters were estimated using linear animal repeatability models that included fixed effects of year-month of observation, age of bull, interaction between semen collection number, and interval between collections for all traits and type of diluter for postcryopreservation traits. The random effects included test-day, permanent environmental, and additive genetic effects of the bull. Based on records from the AI center, we found that semen weight, sperm concentration, and number of straws were moderately heritable (0.18-0.20), whereas motility had a lower heritability (0.02-0.08). Heritability of motility (%) was higher after cryopreservation than before. Genetic correlations among the semen characteristics ranged from unfavorable (-0.35) to favorable (0.93), with standard errors ranging from 0.02 to 0.22. Among the most precise genetic correlation estimates, number of straws made from a batch correlated favorably with semen weight (0.62 ± 0.06) and sperm concentration (0.44 ± 0.08), whereas sperm concentration was negatively correlated with weight (-0.33 ± 0.09). The genetic correlation between motility (%) before and after cryopreservation was 0.64 ± 0.14, and motility change during cryopreservation had a strong favorable genetic correlation with motility after cryopreservation (-0.93 ± 0.02). The estimated genetic correlation (standard error) between the traits volume, concentration, and motility when fresh measured at the performance test station and their respective corresponding traits at the AI center were 0.83 (0.05), 0.78 (0.09), and 0.49 (0.31). The final product at the AI center (number of accepted straws) correlated genetically favorably with all semen characteristic traits recorded at the performance test station (ranging from 0.51 to 0.67). Our results show that the andrology testing done at the performance test station is a resource to identify the genetically best bulls for AI production.

Genome analysis in five Italian beef cattle breeds

Chianina, Marchigiana, Maremmana, Podolica and Romagnola are the main Italian beef cattle breeds, and the quality of their products is largely recognized worldwide. This paper aims to determine the genetic variability and population differentiation by heterozygosity and fixation indices using SNPs data. The dataset was composed of 3,581 animals (Chianina, n = 909; Marchigiana, n = 879; Maremmana, n = 334; Podolica, n = 555; Romagnola, n = 904). The blood samples were collected in ANABIC performance testing station from 1985 to 2019. All the animals were genotyped with the GeneSeek GGP-LDv4 33k SNP chip containing 30,111 SNPs. The genotype quality control for each breed was conducted separately, and SNPs with call rate smaller than 0.95 and minor allele frequency larger than 5% were used for further analysis. Heterozygosity and F IS index were estimated in PLINK v1.9, and F ST index was estimated using the hierstat package of R 4.0.1 software. The genetic analysis highlighted low values of heterozygosity in the improved beef breeds compared to the heritage breeds; moreover, the low values of F IS indicated a positive effect of controlled genetic inbreeding in the studied breeds. The F ST ; analysis confirmed the historical origin of Marchigiana breed and the values are consistent with their common breeding programmes. In this study, the importance of monitoring genetic variability of Italian beef cattle breeds was emphasized in order to maintain breed identity and genetic diversity in the selection process. Keywords: bovine, SNPs, inbreeding References Bonadonna, T. (1976). Etnologia zootecnica. Turin, Italy: UTET. Bongiorni, S. et al. (2016). Transcriptomic investigation of meat tenderness in two Italian cattle breeds. Animal genetics, 47(3), 273-287. Cosentino, C. et al. (2018). Podolian cattle: reproductive activity, milk and future prospects. Italian Journal of Agronomy, 13(3). Dalvit, C. et al. (2008). Breed assignment test in four Italian beef cattle breeds. Meat Science, 80(2), 389-395. D’Andrea, M. et al. (2011). Genetic characterization and structure of the Italian Podolian cattle breed and its relationship with some major European breeds. Italian Journal of Animal Science, 10(4), e54. Goudet, J. (2005). Hierfstat, a package for R to compute and test hierarchical F‐statistics. Molecular Ecology Notes, 5(1), 184-186. Hall, SJG and Bradley, DG. (1995). Conserving livestock breed biodiversity. Tree, 10, 267–270. Holsinger, KE and Weir, BS. (2009). Genetics in geographically structured populations: defining, estimating and interpreting FST. Nature Reviews Genetics, 10(9), 639-650. Jordana, J. et al. (2003). Genetic structure of eighteen local south European beef cattle breeds by comparative F‐statistics analysis. Journal of Animal Breeding and Genetics, 120(2), 73-87. Lasagna, E. et al. (2015). Comparison of four Italian beef cattle breeds by means of functional genes. Italian Journal of Animal Science, 14(1), 3465. Maretto, F. et al. (2012). Genetic relationships among Italian and Croatian Podolian cattle breeds assessed by microsatellite markers. Livestock science, 150(1-3), 256-264. Moioli, B. et al. (2004). Genetic diversity between Piedmontese, Maremmana, and Podolica cattle breeds. Journal of Heredity, 95(3), 250-256. Purcell, S. et al. (2007). PLINK: a tool set for whole-genome association and population-based linkage analyses. The American journal of human genetics, 81(3), 559-575. Sbarra, F. et al. (2009). Heritability of performance test traits in Chianina, Marchigiana and Romagnola breeds. Italian Journal of Animal Science, 8(sup3), 107-109. Smaragdov, MG. et al. (2018). The Assessing the genetic differentiation of Holstein cattle herds in the Leningrad region using Fst statistics. Agricultural and Food Science, 27(2), 96-101. Vincenti, F. et al. (2007). The hypertrophic Marchigiana: physical and biochemical parameters for meat quality evaluation. Italian Journal of Animal Science, 6(sup1), 491-493. Wright, S. (1965). The interpretation of population structure by F-statistics with special regard to systems of mating. Evolution, 395-420.

Serological Cross-Reactivity Between Bovine alphaherpesvirus 2 and Bovine alphaherpesvirus 1 in a gB-ELISA: A Case Report in Italy.

In this study, we demonstrated for the first time in Italy, the serological cross-reactivity between Bovine alphaherpesvirus 2 (BoHV-2) and Bovine alphaherpesvirus 1 (BoHV-1). Five months after arriving at a performance test station in Central Italy, a 6-month-old calf, which was part of a group of 57 animals, tested positive for BoHV-1 in a commercial gB-ELISA test. It was immediately transferred to the quarantine unit and subjected to clinical observation and serological and virological investigations. During this period, the calf showed no clinical signs. The results from laboratory investigations demonstrated the presence of antibodies via competitive glycoprotein B (gB) ELISAs, indirect BoHV-1 ELISAs, and indirect BoHV-2 ELISAs. Furthermore, the plaque reduction assay provided evidence for the presence of antibodies only for BoHV-2, whereas the virus neutralization test showed negative results for both BoHV-1 and BoHV-5. These findings strongly suggest the occurrence of a serological cross-reactivity between BoHV-2 and BoHV-1. Interference of BoHV-2 antibodies in serological BoHV-1 diagnostics should be considered during routine IBR tests, especially when animals are kept in a performance test station.

Genetic correlations between body weight, daily weight gain, and semen characteristic traits in young Norwegian Red bulls

The aim of this study was to estimate genetic parameters for body weight (BW) at 150 d (Bw_150d), and 330 d (Bw_330d) of age and average daily weight gain (Dwg), and to estimate genetic correlations between these traits and semen characteristic traits: volume; concentration (Conc); motility in fresh, 24-h, and 48-h samples (Mot0h, Mot24h, Mot48h); and sperm defects. Data were collected at the performance test station of young Norwegian Red bulls from 2002 to 2012, before selection of bulls for artificial insemination. The weight and growth data consisted of observations for 3,209 bulls, and andrology information was available for up to 2,034 of these bulls. Genetic parameters were estimated using linear animal models. Models for BW and growth traits included the group and year the bull left the station and the pen they occupied during weighing (group-year-pen) and parity of their dam as fixed effects. Models for andrology traits had group-year, age in months (11 to 15), and the interaction between ejaculate number and days since previous collection included as fixed effects. Estimated heritability was 0.14 for Bw_150d, 0.26 for Bw_330d, and 0.34 for Dwg; the estimated genetic correlations among these traits were all favorable. Both BW traits correlated favorably with all the semen characteristic traits (0.20 to 0.76), whereas Dwg was favorably correlated with volume, Mot24h, Mot48h, and sperm defects, and unfavorably correlated with Conc (-0.25) and Mot0h (-0.53). Our results indicate that the genetic correlations between weight and growth traits and semen characteristics depend on the age of the bulls. Although most genetic correlations were favorable, selection for higher daily weight gain between 150 and 330 d might explain the slight negative genetic trends observed for semen characteristics in young Norwegian Red bulls.

Genetic parameter estimates for plasma oxidative status traits in slaughter pigs.

The aim of the present study was to assess the effect of sex and to estimate genetic parameters for several traits related to plasma oxidative status in slaughter pigs, i.e., ferric reducing ability of plasma (FRAP), concentrations of α-tocopherol and malondialdehyde (MDA), and glutathione peroxidase (GPx) activity. Blood samples were collected at slaughter from 477 Piétrain × (Landrace × Large White intercross) pigs of 2 performance test stations. Heritabilities (±SE) of plasma oxidative status traits as well as their phenotypic and additive genetic correlations with animal performance traits were estimated with multiple-trait REML animal models using VCE software. Results displayed no significant difference between barrows and gilts for FRAP and α-tocopherol in plasma. However, gilts had a significantly higher concentration of MDA and lower GPx activity compared with barrows. Heritability estimates were high for GPx (0.55 ± 0.05), and medium to low for α-tocopherol (0.30 ± 0.06), FRAP (0.22 ± 0.05), and MDA (0.15 ± 0.04). Estimated additive genetic and phenotypic correlations between these four traits were generally low, except for a negative additive genetic correlation between FRAP and GPx of -0.45 (±0.23). Additive genetic correlations between plasma oxidative status traits and animal performance traits were also generally absent or low with maximum values of ~0.3. Parameter estimates in this study have to be interpreted with caution because of the small size of the dataset. Nevertheless, it may be concluded that there is considerable additive genetic variance for plasma oxidative status traits in slaughter pigs. More research is warranted on the genetic determination of oxidative stress in farm animals and its relevance in breeding programs.

Genetic analysis of semen characteristic traits in young Norwegian Red bulls

The aim of this study was to estimate genetic parameters and genetic trends for male fertility in Norwegian Red bulls. We analyzed data on semen characteristics traits collected at the performance test station of young bulls from 1994 to 2016, in an andrology test used to ensure acceptable semen quality before being selected as an artificial insemination bull. Traits included were volume, concentration, and motility (percentage of moving sperm cells) in fresh samples and after storing for 24 and 48 h, and sperm defects. The data consisted of 14,972 ejaculates from 3,927 young (11-15 mo) Norwegian Red bulls. Genetic parameters were estimated using bivariate linear animal models that included age in months, group-year, and collection-group (main effect of the interaction between ejaculate number and interval between collections) as fixed effects, and test-day and additive genetic and permanent environment effect of the bull as random effects. Considerable genetic coefficients of variation were found for concentration and volume, with lower values for motility. Estimated heritabilities ranged from 0.02 and 0.03 (for sperm defects and motility in fresh samples) to 0.14 (volume and concentration measured on a continuous scale). All estimated genetic correlations were favorable, but the genetic correlations between volume and concentration and volume and sperm defects were not significantly different from zero. The genetic correlations between concentration and motility traits ranged from 0.53 to 0.83, and those between volume and the motility traits were between 0.24 and 0.57. All traits showed a slightly unfavorable genetic trend. Our results indicate that selection of bulls with better sperm quality is possible.

Relationship between feed efficiency and slaughter traits of French Charolais bulls.

Improving feed efficiency is of interest to French beef producers so as to increase their profitability. To enable this improvement through selection, genetic correlations with production traits need to be quantified. The objective of this study was to estimate the genetic parameters for growth, feed efficiency (FE), and slaughter performance of young beef bulls of the French Charolais breed. Three feed efficiency criteria were calculated: residual feed intake (RFI), residual gain (RG), and ratio of FE. Data on feed intake, growth, and FE were available for 4,675 Charolais bulls tested in performance test stations and fed with pelleted diet. Between 1985 and 1989, 60 among 510 of these bulls were selected to procreate one generation of 1,477 progeny bulls which received the same pelleted diet at the experimental farm in Bourges. In addition to feed intake, growth, and FE traits, these terminal bulls also had slaughter traits of carcass yield, carcass composition, and weight of visceral organs collected. Genetic parameters were estimated using linear mixed animal models. Between performance test bulls and terminal bulls, the genetic correlation of RFI was 0.80 ± 0.18; it was 0.70 ± 0.21 for RG and 0.46 ± 0.20 for FE. For carcass traits, RFI was negatively correlated with carcass yield (-0.18 ± 0.14) and muscle content (-0.47 ± 0.14) and positively with fat content (0.48 ± 0.13). Conversely, RG and FE were positively correlated with carcass yield and muscle content and negatively with fat content. For the three FE criteria, efficient animals had leaner carcass. For visceral organs (as a proportion of empty body weight), RFI was genetically correlated with the proportions of the 5th quarter (0.51 ± 0.17), internal fat (0.36 ± 0.14), abomasum (0.46 ± 0.20), intestines (0.38 ± 0.17), liver (0.36 ± 0.16), and kidneys (0.73 ± 0.11). Conversely, RG and FE were negatively associated with these traits. The high-energy expenditure associated with the high-protein turnover in visceral organs may explain this opposite relationship between FE and the proportion of visceral organs. Selection for final weight and RFI increased growth and FE in progeny, and also improved carcass yield and muscle content in the carcass. To conclude, determinations of growth and feed intake in performance test stations are effective to select bulls to improve their growth, FE, and muscle content in carcass.

Genetic characterization of Markhoz goat breed using microsatellite markers.

The use of molecular markers can support the management of endangered populations and should be combined with appropriate breeding strategies to improve productive traits avoiding the decline of the breed. The genetic variability at 10 microsatellite loci were investigated in a sample of 100 unrelated Markhoz goats (77 females and 23 males). The investigated population was reared at the Sanandaj Markhoz goat Performance Testing Station in Kurdistan, Iran. Markhoz goat, a multipurpose breed, is one of the most valuable genetic resources in Iran. All the studied loci were found to be polymorphic and a total number of 52 alleles were identified with an average number of alleles of 5.2. Moreover, some population genetic indices, such as observed and expected heterozygosity, observed and expected number of alleles, Shannon's index, Nei's expected heterozygosity, and polymorphism information content were also calculated. Despite the decreasing population size, Markhoz goat genetic diversity is still conserved. The breed seems to have a good level of genetic variability and, as a consequence, a potential margin of adaptability to environment and for future genetic improvement.

Modelling and genetic evaluation of Markhoz goat growth curve parameters

The objectives of our study were to compare different non-linear mixed effect models (Brody, Von Bertalanffy, Richards, Gompertz and Logistic) for best description the growth patterns of Markhoz kids, evaluate the influence of environmental (fixed) effects on growth curve parameters of the best-fit growth model and finally estimate the genetic parameters for growth curve characteristics. Live weights of 3678 individuals from the historical archives of the Markhoz Goat Performance Testing Station (in Sanandaj), which were collected from birth to 365 days of age during 1992 to 2015, were used in the analysis. Models were fitted according to the stochastic approximation expectation-maximization (SAEM) procedure implemented in R package SAEMIX. All studied mixed models described the growth pattern in Markhoz goat, except Richards model. However, the Brody model best fit the data. The analysis of variance on the growth curve parameters (at the individual level) showed that among the fixed effects (i.e., sex, birth type, age of dam and year of birth) for the Brody model, only age of dam had no effect on any of the growth parameters. Estimates of heritability for growth curve parameters were low, with 0.067 ± 0.011, 0.063 ± 0.010 and 0.044 ± 0.001 for mature weight (a), constant of integration (b) and rate of maturing (k), respectively. Low heritability estimates suggest that the environment is not favorable for expression of genetic potential of Markhoz kids. The negative genetic (−0.866 ± 0.000) and phenotypic (−0.723 ± 0.008) correlations between the parameters a and k indicates that animals with lower growth rates are more likely to reach higher weight values when adults.

Polymorphism of GDF9 and BMPR1B genes and their association with litter size in Markhoz goats.

The main objective of this study was to investigate the polymorphism of GDF9 and BMPR1B genes and their relationship with litter size in Markhoz goats. The polymorphism of GDF9 and BMPR1B genes as well-documented genes regarding fecundity in sheep and goat was investigated using RFLP-PCR and a tetra-primer amplification refractory mutation system-PCR (T-ARMS-PCR) in Markhoz goats. The 164 blood samples were collected from the raised goats in Sanandaj Markhoz goat Performance Testing Station. The DNA extraction was carried out by salting-out procedure, and then, PCR was performed using four and two pairs of primers to detect polymorphism in GDF9 and BMPR1B genes, respectively. To disclose GDF9 loci polymorphism, PCR products were digested with SspI (G3288A), PvuII (G423A), MvaI (A959C) and MspI (G1189A) restriction enzymes. The results showed that these mutations are available in tested animals. Parity had no significant effect on litter size. Also, the effects of different genotypes of GDF9 and BMPR1B had no significant effect on litter size. Further studies with a high number of animals with minimum relatedness for testing the association of these SNPs and others in the fecundity genes with reproductive traits may be worthwhile.

The Relationship between carcass lean meat percentage and MRI data obtained on hams of entire boars

The study on the relationship between lean meat percentage (LMP) and ham measures assessed by means of magnetic resonance imaging (MRI) was performed on 20 carcasses of entire boars from one performance testing station in Germany. In addition, linear carcass measurements were taken, according to the standard protocol for stationary performance testing, to be used to estimate LMP by the Bonner Formula. Finally, manual dissection was serving as reference, for LMP. The correlations between the true LMP and linear measurements Bonner Formula were medium strong, but not in all cases statistically significant. On the other hand, the correlations between ham data obtained by MRI and reference LMP had stronger and significant correlations. Three new formulas were constructed in order to evaluate the LMP of entire boars. The best prediction ability was found when combining linear measurements with one MRI measure – the widest circumference of the ham (R2 = 0.67 and RMSEP = 1.395). Interestingly, the proposed equation has variables that can be easily taken; three of them are taken regularly for Bonner Formula estimation and MRI based ham circumference aided to improve the prediction accuracy, a measure that could also be acquired by the simple use of meter or rope.

A RPC test station based on ROOT and VME

Due to its advantages in large-area application situations, the R&D of the resistive plate chamber (RPC) has always been carried out. A performance test station for RPC R&D has been designed and developed based on the VME bus and ROOT in Linux. This system can be customized expediently according to the requirements of different tests, which facilitates detector R&D because of its automatic HV scan, especially for long-term test. With this system, we have implemented the RPC performance test, including the efficiency curve, counting rate, dark current and charge and timing resolution.

Prediction of Carcass Meat Percentage in Young Pigs Using Linear Regression Models and Artificial Neural Networks

Abstract One of the approaches to improving performance testing of pigs is to look for mathematical solutions to increase the accuracy of calculations. This is mainly done through improvement of linear regression equations based on current data on performance tested pigs in Poland. The advances in computer technology and the improvements in mathematical analysis have made it possible to use artificial neural networks (ANNs) for prediction of carcass meat percentage in young pigs. The aim of the study was to compare the potential for live estimation of carcass meat percentage in pigs using two computational methods: linear regression equations and ANNs. The experiment used 654 gilts of six breeds, which were subjected to performance testing and slaughter analysis at the Pig Performance Testing Station (SKURTCh). The collected data were used to train ANNs to estimate carcass meat percentage in young pigs. Training was performed using the Levenberg- Marquardt algorithm. Next, meatiness estimated by ANNs was compared with the results obtained using linear modelling. It is concluded that based on the fattening and slaughter performance test results of live pigs, artificial neural networks (SSN23) are significantly more accurate in estimating carcass meat percentage in young pigs compared to the three-variable linear regression model 1. The difference in meatiness estimation between SSN23 and the four-variable linear regression model 2 was statistically non-significant in most of the breeds except Duroc and Pietrain, where the meatiness of young animals was estimated more accurately by the linear regression model.

Herd-of-origin effect on the post-weaning performance of centrally tested Nellore beef cattle.

The objective of a performance test station is to evaluate the performance of potential breeding bulls earlier in order to decrease the generation interval and increase genetic gain as well. This study evaluates the herd-of-origin influence on end-of-test weight (ETW), average daily weight gain during testing (ADG), average daily weight gain during the adjustment period (ADGadj), rib eye area (REA), marbling (MARB), subcutaneous fat thickness (SFT), conformation (C), early finishing (EF), muscling (M), navel (N) and temperament (T) scores, and scrotal circumference (SC) of Nellore cattle that underwent a performance test. We evaluated 664 animals that participated in the performance tests conducted at the Center for Performance CRV Lagoa between 2007 and 2012. Components of variance for each trait were estimated by an animal model (model 1), using the restricted maximum likelihood method. An alternative animal model (model 2) included, in addition to the fixed effects present in S1, the non-correlated random effect of herd-year (HY). A significant HY effect was observed on ETW, REA, SFT, ADGadj, C, and Cw (p < 0.05). The estimated heritability of all traits decreased when the HY effect was included in the model; also, the bull rank, in deciles, changed significantly for traits ETW, REA, SFT, and C. The adjustment period did not completely remove the environmental effect of herd of origin on ETW, REA, SFT, and C. It is recommended that the herd-of-origin effect should be included in the statistical models used to predict the breeding values of the participants of these performance tests.

Genomewide study and validation of markers associated with production traits in German Landrace boars1

We present results from a genomewide association study (GWAS) and a single-marker association study. The GWAS was performed with the Illumina PorcineSNP60 BeadChip from which 5 markers were selected for a validation analysis. Genetic effects were estimated for feed intake, weight gain, and traits of fat and muscle tissue in German Landrace boars kept on performance test stations. The GWAS was performed in a population of 288 boars and the validation study for another 432 boars. No statistically significant effect was found in the GWAS after adjusting for multiple testing. Effects of 2 markers, which were significant genomewide before correction for multiple testing (P < 0.00005), could be confirmed in the validation study. The major allele of marker ALGA0056781 on SSC1 was positively associated with both higher weight gain and fat deposition. The effect on live-weight gain was 2.25 g/d in the GWAS (P = 0.0003) and 3.73 g/d in the validation study (P = 0.01) and for back fat thickness was 0.15 mm in the GWAS (P < 0.0001) and 0.20 mm in the validation study (P = 0.02). The marker had similar effects on test-day weight gain (GWAS: 3.85 g/d, P = 0.001; validation study: 6.80 g/d, P = 0.003) and back fat area (GWAS: 0.27 cm(2), P < 0.0001; validation study: 0.35 cm(2), P = 0.03). Marker ASGA0056782 on SSC13 was associated with live-weight gain. The major allele had negative effects in both studies (GWAS: -4.88 g/d, P < 0.0001; validation study: -3.75 g/d, P = 0.02). The effects of these 2 markers would have been excluded based on the GWAS alone but were shown to be significantly trait associated in the validation study indicating a false-negative result. The G protein-coupled receptor 126 (GPR126) gene approximately 200 kb downstream of marker ALGA0001781 was shown to be associated with human height and therefore might explain the association with weight gain in pigs. Several traits were affected in an economically desired direction by the minor allele of the markers, pointing to the possibility of improvement through further selection.

Genetic evaluation of the growth of beef bulls at a performance test station

1. Recent developments in cattle, pig, sheep and horse breeding - a review Alena Svitáková, Jitka Schmidová, Petr Pešek, Alexandra Novotná Acta Veterinaria Brno CrossRef

Recent developments in cattle, pig, sheep and horse breeding - a review

The aim of this review was to summarize new genetic approaches and techniques in the breeding of cattle, pigs, sheep and horses. Often production and reproductive traits are treated separately in genetic evaluations, but advantages may accrue to their joint evaluation. A good example is the system in pig breeding. Simplified breeding objectives are generally no longer appropriate and consequently becoming increasingly complex. The goal of selection for improved animal performance is to increase the profit of the production system; therefore, economic selection indices are now used in most livestock breeding programmes. Recent developments in dairy cattle breeding have focused on the incorporation of molecular information into genetic evaluations and on increasing the importance of longevity and health in breeding objectives to maximize the change in profit. For a genetic evaluation of meat yield (beef, pig, sheep), several types of information can be used, including data from performance test stations, records from progeny tests and measurements taken at slaughter. The standard genetic evaluation method of evaluation of growth or milk production has been the multi-trait animal model, but a test-day model with random regression is becoming the new standard, in sheep as well. Reviews of molecular genetics and pedigree analyses for performance traits in horses are described. Genome – wide selection is becoming a world standard for dairy cattle, and for other farm animals it is under development.

Analysis of the Possibility of Improving the Indicators of Pork Quality Through Selection with Particular Consideration of Intramuscular Fat (MF) Content / Analiza możliwości poprawy wskaźników jakości wieprzowiny na drodze selekcji ze szczególnym uwzględnieniem zawartości tłuszczu śródmięśniowego (IMF)

Abstract The aim of the study was to estimate coefficients of heritability for intramuscular fat (IMF) content and other fattening, slaughter and meat quality traits of the pig breeds raised in Poland. In addition, genetic correlations were estimated between IMF content and a group of fattening, slaughter and meat quality traits, which enables this parameter to be included in the BLUP estimation of breeding value. The experiment used Polish Landrace (PL), Polish Large White (PLW), Puławska, Hampshire, Duroc, Pietrain and line 990 animals. A total of 4430 gilts of these breeds, tested at Pig Performance Testing Stations (SKURTCh), were investigated. Heritability of IMF was at intermediate level for the two most common breeds raised in Poland (h2 = .318 for PLW, h2 = .291 for PL). In the group of meat quality traits, high heritability was noted for meat colour lightness (L*) measured by Minolta (from h2 = .453 to h2 = .572). No relationships were found between IMF level and indicators of fattening performance. The highest value observed in this group of traits concerned the genetic relationship with daily feed intake (rG = .227) for the entire group of animals. For the PLW and PL breeds, these relationships were with feed conversion (kg/kg gain) (rG = .151 and rG = .167, respectively). One of the higher relationships observed were genetic correlations with water holding capacity (above rG = -.3) and, for the PLW and PL breeds, with meat redness (a*), which amounted to rG = .155 and rG = .143, respectively.