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The study explored the entrepreneurial prospects of animal breeding and genetics from the viewpoints of undergraduates at two Nigerian institutions. The study looked at how undergraduates perceive the potential for entrepreneurship in the fields of animal breeding and genetics; it determined whether they intend to pursue entrepreneurship in any of the identified fields of the discipline; and examined the relevance of the curriculum to the entrepreneurship knowledge needed to succeed in the fields; and identified the difficulties that these undergraduates might face in their entrepreneurial intention endeavors. The study adopted a qualitative methodology to explore the entrepreneurial prospects of animal breeding and genetics from the viewpoints of undergraduates at two Nigerian institutions. 30 undergraduate students from two universities were taken to represent the sample for the study. An open-ended survey created on Google form was used for the collection of data. The link of the Google form was sent to the students’ platform in the Department of Animal Genetics in the two selected universities. The findings demonstrated that Animal Breeding and Genetics undergraduate students perceive the potential for entrepreneurship in animal breeding and genetics to be numerous including setting up animal clinic, animal breeding laboratory, establishing a poultry business, setting up a consultancy outlet on animal breeding and genetics, among others. Majority of the undergraduate students indicate their intention to pursue entrepreneurship in animal breeding and genetics instead of looking for the white-collar jobs. Furthermore, the current curriculum in Animal Breeding and Genetics in the two universities are very relevant to the fields and the knowledge they have gathered so far is enough to succeed if taking into entrepreneurship after the completion of the bachelor’s degree programme. The challenges envisaged by the respondents include lack of initial capital to sett

The study explored the entrepreneurial prospects of animal breeding and genetics from the viewpoints of undergraduates at two Nigerian institutions. The study looked at how undergraduates perceive the potential for entrepreneurship in the fields of animal breeding and genetics; it determined whether they intend to pursue entrepreneurship in any of the identified fields of the discipline; and examined the relevance of the curriculum to the entrepreneurship knowledge needed to succeed in the fields; and identified the difficulties that these undergraduates might face in their entrepreneurial intention endeavors. The study adopted a qualitative methodology to explore the entrepreneurial prospects of animal breeding and genetics from the viewpoints of undergraduates at two Nigerian institutions. 30 undergraduate students from two universities were taken to represent the sample for the study. An open-ended survey created on Google form was used for the collection of data. The link of the Google form was sent to the students’ platform in the Department of Animal Genetics in the two selected universities. The findings demonstrated that Animal Breeding and Genetics undergraduate students perceive the potential for entrepreneurship in animal breeding and genetics to be numerous including setting up animal clinic, animal breeding laboratory, establishing a poultry business, setting up a consultancy outlet on animal breeding and genetics, among others. Majority of the undergraduate students indicate their intention to pursue entrepreneurship in animal breeding and genetics instead of looking for the white-collar jobs. Furthermore, the current curriculum in Animal Breeding and Genetics in the two universities are very relevant to the fields and the knowledge they have gathered so far is enough to succeed if taking into entrepreneurship after the completion of the bachelor’s degree programme. The challenges envisaged by the respondents include lack of initial capital to sett

The study explored the entrepreneurial prospects of animal breeding and genetics from the viewpoints of undergraduates at two Nigerian institutions. The study looked at how undergraduates perceive the potential for entrepreneurship in the fields of animal breeding and genetics; it determined whether they intend to pursue entrepreneurship in any of the identified fields of the discipline; and examined the relevance of the curriculum to the entrepreneurship knowledge needed to succeed in the fields; and identified the difficulties that these undergraduates might face in their entrepreneurial intention endeavors. The study adopted a qualitative methodology to explore the entrepreneurial prospects of animal breeding and genetics from the viewpoints of undergraduates at two Nigerian institutions. 30 undergraduate students from two universities were taken to represent the sample for the study. An open-ended survey created on Google form was used for the collection of data. The link of the Google form was sent to the students’ platform in the Department of Animal Genetics in the two selected universities. The findings demonstrated that Animal Breeding and Genetics undergraduate students perceive the potential for entrepreneurship in animal breeding and genetics to be numerous including setting up animal clinic, animal breeding laboratory, establishing a poultry business, setting up a consultancy outlet on animal breeding and genetics, among others. Majority of the undergraduate students indicate their intention to pursue entrepreneurship in animal breeding and genetics instead of looking for the white-collar jobs. Furthermore, the current curriculum in Animal Breeding and Genetics in the two universities are very relevant to the fields and the knowledge they have gathered so far is enough to succeed if taking into entrepreneurship after the completion of the bachelor’s degree programme. The challenges envisaged by the respondents include lack of initial capital to sett

Background Conventional pig housing and management conditions are associated with gastrointestinal pathophysiology and disease susceptibility in early life. Developing new strategies to reduce both therapeutic and prophylactic antibiotic use is urgent for the sustainable swine production globally. To this end, housing methodology providing effective environmental enrichment could be a promising alternative approach to reduce antibiotic usage, as it has been proven to positively influence pig welfare and immune status and reduce susceptibility to infections. It is, however, poorly understood how this enriched housing affects systemic and local pulmonary immune status and gut microbiota colonization during early life. In the present study, we compared the effects of two housing conditions, i.e., conventional housing: (CH) versus enriched housing (EH), on immune status and gut microbiota from birth until 61 days of age. Results The expected benefits of enrichment on pig welfare were confirmed as EH pigs showed more positive behaviour, less aggression behaviour during the weaning transition and better human animal relation during the post weaning phase. Regarding the pigs’ immune status, EH pigs had higher values of haemoglobin and mean corpuscular volume in haematological profiles and higher percentages of T cells and cytotoxic T cells in peripheral blood. Furthermore, EH pigs showed higher ex vivo secretion of IL1ß and TNF-α after lipopolysaccharide stimulation of whole blood than CH pigs. The structure of the developing faecal microbiota of CH and EH pigs significantly differed as early as day 12 with an increase in the relative abundance of several bacterial groups known to be involved in the production of short chain fatty acids, such as Prevotella_2, Christensenellaceae_R_7_group and Ruminococcus gauvreauii group. Furthermore, the main difference between both housing conditions post weaning was that on day 61, CH pigs had significantly larger

Genetic selection has been a very successful tool for the long-term improvement of livestock populations, and the rapid adoption of genomic selection over the last decade has doubled the rate of gain in some populations. However, the full expression of genetic potential requires that animals are placed in environments that support such performance. Increasingly complex dairy cattle production systems require that all aspects of animal performance are measured across individuals’ lifetimes. Selection emphasis is shifting away from traits related to animal productivity towards those related to efficient resource utilization and increased animal welfare. However, phenotypes for many of these new traits are difficult or expensive to measure, or both. This is driving interest in sensor-based systems that provide continuous measurements of the farm environment, individual animal performance, and detailed milk composition. The goal of phenomics is to provide information for making decisions related to on-farm management, as well as genetic improvement. However, many challenges accompany these new technologies, including a lack of standardization, the need for high-speed Internet connections, increased computational requirements, and training to integrate these tools with more traditional management tools. There also is a lack of translational research on the use of these data for real-time precision management. We will identify opportunities and challenges associated with phenomics and discuss on-farm applications of these new tools.

Runs of homozygosity (ROH) are continuous stretches of homozygous genotypes in an individual that have been passed down from a common ancestor and can be used to accurately characterize genomic data. These ROH are correlated with other measures of inbreeding and have been applied to quantify individual autozygosity. The aim of this study was to detect and describe ROH in the turkey genome and estimate and compare measures of pedigree-based inbreeding coefficients (FPED) and genomic-based inbreeding coefficients estimated from ROH (FROH) and the genomic relationship matrix (FGRM). Pedigree records (n = 2,616,890) and genotypic records (n = 6,371) were available from three purebred turkey (Meleagris gallopavo) lines. Genotypic records were collected between 2013 and 2019 and were obtained using a dense single nucleotide polymorphism array (56,452 SNP). The overall mean length of detected ROH per animal was 2.87±0.29 Mb and mean number of ROH per animal was 84.87±8.79. Short ROH with lengths of 1–2 Mb long were the most abundant throughout the genome, accounting for approximately 45% of the identified segments. Mean ROH coverage differed greatly between chromosomes and lines. Across all lines, genomic derived inbreeding coefficients (FROH=0.27; FGRM=0.32) were higher than coefficients estimated from pedigree records (FPED=0.14). Ranges of correlations between FROH and FPED (0.19–0.31), FROH and FGRM (0.68–0.73), and FPED and FGRM (0.17–0.30) were estimated. Results from the current research provide a fundamental description of inbreeding in the turkey genome which is critical considering the growing concerns of the detrimental effects of increased inbreeding on fitness and health in livestock production. The knowledge gained from this study may subsequently be used to evaluate and maintain genetic diversity that is necessary for genetic improvement and minimizing inbreeding in turkey breeding programs.

Seminal plasma is a key biological fluid that modulates sperm function in the reproduction process. However, its role in sperm biotechnologies is scarce in poultry. The aims of the present study were to study the amino acids profile and total proteins of seminal plasma in 12 Spanish chicken breeds and to investigate the role of seminal plasma on cryoresistance of rooster sperm. To investigate the role of seminal plasma on cryoresistance, diluted pooled semen samples were cryopreserved in the presence and absence of seminal plasma. Glutamic acid was the most abundant free amino acid in seminal plasma, followed by alanine, serine, valine, and glycine. There was an influence of breed (P<0.05) on the percentage of viable sperm after freezing-thawing of samples with seminal plasma. Cluster analysis revealed that White Prat, Black Castellana, Blue Andaluza, Quail Castellana, and Red-Barred Vasca returned the best freezing-thawing response (good freezers). There was a positive correlation between seminal plasma concentrations of valine, isoleucine lysine, leucine and post thaw viability. The evaluation of fertilization capacity of frozen-thawed semen from the breeds White Prat (‘good freezer’) and Black-Red Andaluza (‘bad freezer’) showed that good freezer had higher fertility (20/68, 29.4%) compared to bad freezer breed (14/76, 18.4%), even if the difference was not significant (P = 0.08). The TUNEL assay revealed that freezing/thawing procedures in presence of seminal plasma provoked higher DNA fragmentation in most of the breeds, with a positive correlation between seminal alanine, valine, isoleucine, methionine, leucine, tyrosine, phenylalanine concentrations and DNA integrity. DNA fragmentation was lower in absence of seminal plasma and the breed effect on sperm viability was highly reduced. It is concluded that specific seminal plasma amino acids were associated with post-thaw percentage of viable sperm and DNA integrity. The removal of seminal plasma decreases th

Genome wide association study was conducted using a mixed linear model (MLM) approach that accounted for family structure to identify single nucleotide polymorphisms (SNPs) and candidate genes associated with body weight (BW) and feed efficiency (FE) traits in a broiler chicken population. The results of the MLM approach were compared with the results of a general linear model approach that does not take family structure in to account. In total, 11 quantitative trait loci (QTL) and 21 SNPs, were identified to be significantly associated with BW traits and 5 QTL and 5 SNPs were found associated with FE traits using MLM approach. Besides some overlaps between the results of the two GWAS approaches, there are considerable differences in the detected QTL. Even though the genomic inflation factor (λ) values indicate that there is no strong family structure in this population, using models that account for the existing family structure may reduce bias and increase accuracy of the estimated SNP effects in the association analysis. The SNPs and candidate genes identified in this study provide information on the genetic background of BW and FE traits in broiler chickens and might be used as prior information for genomic selection.

After publication of this work [1], we noticed that there was an error: the formula to calculate the standard error of the estimated correlation.

Background: High levels of pairwise linkage disequilibrium (LD) in single nucleotide polymorphism (SNP) array or whole-genome sequence data may affect both performance and efficiency of genomic prediction models. Thus, this warrants pruning of genotyping data for high LD. We developed an algorithm, named SNPrune, which enables the rapid detection of any pair of SNPs in complete or high LD throughout the genome. Methods: LD, measured as the squared correlation between phased alleles (r 2), can only reach a value of 1 when both loci have the same count of the minor allele. Sorting loci based on the minor allele count, followed by comparison of their alleles, enables rapid detection of loci in complete LD. Detection of loci in high LD can be optimized by computing the range of the minor allele count at another locus for each possible value of the minor allele count that can yield LD values higher than a predefined threshold. This efficiently reduces the number of pairs of loci for which LD needs to be computed, instead of considering all pairwise combinations of loci. The implemented algorithm SNPrune considered bi-allelic loci either using phased alleles or allele counts as input. SNPrune was validated against PLINK on two datasets, using an r 2 threshold of 0.99. The first dataset contained 52k SNP genotypes on 3534 pigs and the second dataset contained simulated whole-genome sequence data with 10.8 million SNPs and 2500 animals. Results: SNPrune removed a similar number of SNPs as PLINK from the pig data but SNPrune was almost 12 times faster than PLINK. From the simulated sequence data with 10.8 million SNPs, SNPrune removed 6.4 and 1.4 million SNPs due to complete and high LD. Results were very similar regardless of whether phased alleles or allele counts were used. Using allele counts and multi-threading with 10 threads, SNPrune completed the analysis in 21 min. Using a sliding window of up to 500,000 SNPs, PLINK removed ~ 43,000 less SNP

Background: Accurate genomic prediction requires a large reference population, which is problematic for traits that are expensive to measure. Traits related to milk protein composition are not routinely recorded due to costly procedures and are considered to be controlled by a few quantitative trait loci of large effect. The amount of variation explained may vary between regions leading to heterogeneous (co)variance patterns across the genome. Genomic prediction models that can efficiently take such heterogeneity of (co)variances into account can result in improved prediction reliability. In this study, we developed and implemented novel univariate and bivariate Bayesian prediction models, based on estimates of heterogeneous (co)variances for genome segments (BayesAS). Available data consisted of milk protein composition traits measured on cows and de-regressed proofs of total protein yield derived for bulls. Single-nucleotide polymorphisms (SNPs), from 50K SNP arrays, were grouped into non-overlapping genome segments. A segment was defined as one SNP, or a group of 50, 100, or 200 adjacent SNPs, or one chromosome, or the whole genome. Traditional univariate and bivariate genomic best linear unbiased prediction (GBLUP) models were also run for comparison. Reliabilities were calculated through a resampling strategy and using deterministic formula. Results: BayesAS models improved prediction reliability for most of the traits compared to GBLUP models and this gain depended on segment size and genetic architecture of the traits. The gain in prediction reliability was especially marked for the protein composition traits β-CN, κ-CN and β-LG, for which prediction reliabilities were improved by 49 percentage points on average using the MT-BayesAS model with a 100-SNP segment size compared to the bivariate GBLUP. Prediction reliabilities were highest with the BayesAS model that uses a 100-SNP segment size. The bivariate versions of our BayesAS models resulted in extra gains

Background: Reproductive traits such as number of stillborn piglets (SB) and number of teats (NT) have been evaluated in many genome-wide association studies (GWAS). Most of these GWAS were performed under the assumption that these traits were normally distributed. However, both SB and NT are discrete (e.g. count) variables. Therefore, it is necessary to test for better fit of other appropriate statistical models based on discrete distributions. In addition, although many GWAS have been performed, the biological meaning of the identified candidate genes, as well as their functional relationships still need to be better understood. Here, we performed and tested a Bayesian treatment of a GWAS model assuming a Poisson distribution for SB and NT in a commercial pig line. To explore the biological role of the genes that underlie SB and NT and identify the most likely candidate genes, we used the most significant single nucleotide polymorphisms (SNPs), to collect related genes and generated gene-transcription factor (TF) networks. Results: Comparisons of the Poisson and Gaussian distributions showed that the Poisson model was appropriate for SB, while the Gaussian was appropriate for NT. The fitted GWAS models indicated 18 and 65 significant SNPs with one and nine quantitative trait locus (QTL) regions within which 18 and 57 related genes were identified for SB and NT, respectively. Based on the related TF, we selected the most representative TF for each trait and constructed a gene-TF network of gene-gene interactions and identified new candidate genes. Conclusions: Our comparative analyses showed that the Poisson model presented the best fit for SB. Thus, to increase the accuracy of GWAS, counting models should be considered for this kind of trait. We identified multiple candidate genes (e.g. PTP4A2, NPHP1, and CYP24A1 for SB and YLPM1, SYNDIG1L, TGFB3, and VRTN for NT) and TF (e.g. NF-κB and KLF4 for SB and SOX9 and ELF5 for NT), which were consistent with known new

The optimal ratio of omega-6 to omega-3 polyunsaturated fatty acids (PUFAs) is important for keeping the homeostasis of biological processes and metabolism, yet the underlying biological mechanism is poorly understood. The objective of this study was to identify changes in the pig liver transcriptome induced by a diet enriched with omega-6 and omega-3 fatty acids and to characterize the biological mechanisms related to PUFA metabolism. Polish Landrace pigs (n = 12) were fed diet enriched with linoleic acid (LA, omega-6) and α-linolenic acid (ALA, omega-3) or standard diet as a control. The fatty acid profiling was assayed in order to verify how feeding influenced the fatty acid content in the liver, and subsequently next-generation sequencing (NGS) was used to identify differentially expressed genes (DEG) between transcriptomes between dietary groups. The biological mechanisms and pathway interaction networks were identified using DAVID and Cytoscape tools. Fatty acid profile analysis indicated a higher contribution of PUFAs in the liver for LA- and ALA-enriched diet group, particularly for the omega-3 fatty acid family, but not omega-6. Next-generation sequencing identified 3565 DEG, 1484 of which were induced and 2081 were suppressed by PUFA supplementation. A low ratio of omega-6/omega-3 fatty acids resulted in the modulation of fatty acid metabolism pathways and over-representation of genes involved in energy metabolism, signal transduction, and immune response pathways. In conclusion, a diet enriched with omega-6 and omega-3 fatty acids altered the transcriptomic profile of the pig liver and would influence animal health status.

Trait values of individuals are affected not only by their genetic makeup, but also by environmental factors and interactions with other individuals. The heritable effect of an individual on the trait values of other individuals it interacts with is known as an indirect genetic effect (IGE). Such IGEs may affect response to selection. Fish selected for high growth rate, for example, have been shown to be more aggressive and competitive, which may reduce the observed response in growth rate. The main objective of this study is to quantify the genetic and non-genetic indirect effects for harvest weight in the GIFT strain of Nile tilapia. A total of 6330 fish with harvest weight information were used to estimate genetic and non-genetic parameters. A bivariate analysis of harvest weight and survival was conducted by fitting different mixed models to investigate the presence of IGEs and other non-genetic effects. The full set of genetic parameters could not be estimated simultaneously with the inclusion of maternal common environmental effects. A confounding between maternal common environmental effects and direct genetic effects resulted from the mating strategy, where one sire was mated to only one or two dams. A 1 male to 2 females mating design is common in aquaculture, but it has limited power to estimate genetic parameters. Models without maternal common environmental effects showed significant IGE on harvest weight, which contributed 48% of total heritable variance. Models with maternal common environmental effects suggested the presence of IGE. The direct-indirect genetic correlation for harvest weight was negative (-. 0.38. ±. 0.19), indicating that traditional selection, if performed in an environment where the fish have to compete with each other for the resources, will increase competition. A strongly negative genetic correlation between direct effects on survival and indirect effects on harvest weight (-. 0.79. ±. 0.30) showed that individuals with better ge

In the past decade, biobanking has fuelled great scientific advances in the human medical sector. Well-established domesticated animal biobanks and integrated networks likewise harbour immense potential for great scientific advances with broad societal impacts, which are currently not being fully realised. Political and scientific leaders as well as journals and ethics committees should help to ensure that we are well equipped to meet future demands in livestock production, animal models, and veterinary care of companion animals.

Records (with and without coordinates) representing germplasm accessions and sightings of the wild relatives of potato. These records were used as input to assess the ex situ conservation urgency of 73 wild relatives of potato

Dataset belonging to PLOS ONE article "Selection based on indirect genetic effects for growth, environmental enrichment and coping style affect the immune status of pigs".

Transcriptional profiling of eight normal adult chicken tissues in 10-week old brown (lohmann brown) hens, the eight tissues include brain, bursa of Fabricius, jejunum, kidney, liver, lung, spleen, thymus. Keywords: normal chicken tissues, transcriptional profiling.

The aim of this study was to estimate phenotypic and genetic parameters for body condition scores (BCS) from the Dutch type classification system. Data included 108,809 Holstein (H) and 26,208 Red-and-White (R) heifers from 9701 herds that were scored once during lactation on a 1 to 9 scale (1 = emaciated and 9 = obese). Mean BCS for H and R data were 4.50 and 4.94, respectively. The BCS decreased as the percentage of Holstein genes increased. For both breeds, BCS after calving was about 5.6 and BCS was lowest around wk 11. For H heifers, mean BCS at drying off was about 0.8 lower than BCS at calving, whereas for R heifers BCS was at about the same level as at calving. Variance components were estimated using an animal model including the effects of herd x visit, classifier, age at calving, DIM, and genetic group. The random herd x visit effect explained about 10 to 15␘f the phenotypic variation. Heritabilities ranged from 0.24 to 0.38, depending on breed and lactation period. Genetic correlations between BCS observations in bimonthly lactation periods were close to unity, especially for H. It was concluded that BCS data collected by type classifiers can well be used for genetic evaluation and that genetic variation between animals for BCS-change patterns is a small component of the overall variation in BCS.

This article presents a deterministic method to predict rates of inbreeding (ΔF) for typical livestock improvement schemes. The method is based on a recently developed general theory to predict rates of inbreeding, which uses the concept of long-term genetic contributions. A typical livestock breeding population was modeled, with overlapping generations, BLUP selection, and progeny testing of male selection candidates. Two types of selection were practiced: animals were either selected by truncation on estimated breeding values (EBV) across age classes, or the number of parents selected from each age class was set to a fixed value and truncation selection was practiced within age classes. Bulmer's equilibrium genetic parameters were obtained by iterating on a pseudo-BLUP selection index and ΔF was predicted for the equilibrium situation. Predictions were substantially more accurate than predictions from other available methods, which ignore the effect of selection on ΔF. Predictions were accurate for schemes with up to 20 sires. Predicted ΔF was somewhat too low for schemes with more than 20 sires, which was due to the use of simple linear models to predict genetic contributions. The present method provides a computationally feasible (i.e., deterministic) tool to consider both the rate of inbreeding and the rate of genetic gain when optimizing livestock improvement schemes.

The objective of this study was to estimate the effects of β-κ-casein (CN) haplotypes on first-lactation milk production traits. The β-κ-CN haplotypes were deduced using information on β- and κ-CN genotypes of cows and their sires for 16,973 Finnish Ayrshire cows that had at least nine paternal half sibs. Effects of CN haplotypes on milk production traits were estimated for one haplotype at a time using an animal model, which included the fixed effects for calving year and month, age at calving, days open, β-lactoglobulin, and a β-κ-CN haplotype. Differences in milk production traits were also estimated between haplotype combinations A1A A2B and A1B A2A within β-κ-CN genotype A1A2AB and between combinations A1E A2A and A1A A2E within genotype A1A2AE. The β-κ-CN haplotypes A2A and A2B were associated with high milk and protein yields and low fat content, and those that included the β-CN A1 allele were associated with low yields and high fat content. Protein content was affected by the κ-CN locus; haplotype A1B was associated with high protein content and A1E was with low protein content. The haplotype combination A1A A2B was associated with 140 kg more milk yield (P = 0.045) and 0.03 percentage units less protein content (P = 0.055) than combination A1B A2A, and combination A1A A2E showed 0.02 percentage units greater protein content (P = 0.098) than A1E A2A. These results indicate that genes linked to the CN loci contribute to the variation in milk yield and protein content.

The objective of this study was to investigate whether pigs with different genetic merit for survival differed in birth weight, progress of farrowing, early postnatal behavior, or rectal temperature within 24 h after birth. On a nucleus farm in Rio Verde, Brazil, information was collected on 280 pigs, originating from 25 litters with known estimated breeding values for pig survival (EBVps). Litters were selected in such a way that a continuous range of EBVps with a maximum genetic contrast was achieved. Birth weight was recorded for all pigs. Indicators for progress of farrowing were birth intervals and duration of farrowing. Behavioral indicators of pig vitality were time until first upright standing (FUS), time until first udder contact (FUC), time until first teat in mouth (FTM), and time until first colostrum uptake (FCU). Rectal temperature was measured within 24 h after birth. Farrowing survival and early postnatal survival (within 3 d after farrowing) were registered. Farrowing survival and early postnatal survival both increased with increasing EBVps (farrowing survival: P = 0.007; early postnatal survival: P = 0.027). Birth weight decreased with increasing EBVps (P = 0.01). Birth intervals tended to increase with increasing EBVps (P = 0.10) and duration of farrowing was not related to EBVps. Time until first teat in mouth increased with increasing EBVps (P = 0.05), but the other behavioral indicators of pig vitality were not related to EBVps. Rectal temperature within 24 h after birth was not related to EBVps. Pigs with a higher genetic merit for survival have a lower birth weight but nevertheless have an increased farrowing survival and early postnatal survival. Their increased survival cannot be explained by differences in progress of farrowing, early postnatal behavior, or rectal temperature within 24 h after birth.

The effect of non-random mating on genetic response was compared for populations with discrete generations. Mating followed a selection step where the average coancestry of selected animals was constrained, while genetic response was maximised. Minimum coancestry (MC), Minimum coancestry with a maximum of one offspring per mating pair (MC1) and Minimum variance of the relationships of offspring (MVRO) mating schemes resulted in a delay in inbreeding of about two generations compared with Random, Random factorial and Compensatory mating. In these breeding schemes where selection constrains the rate of inbreeding, F, the improved family structure due to non-random mating increased genetic response. For schemes with F constrained to 1.0nd 100 selection candidates, genetic response was 22␑igher for the MC1 and MVRO schemes compared with Random mating schemes. For schemes with a less stringent constraint on F or more selection candidates, the superiority of the MC1 and MVRO schemes was smaller (5-6Ž In general, MC1 seemed to be the preferred mating method, since it almost always yielded the highest genetic response. MC1 mainly achieved these high genetic responses by avoiding extreme relationships among the offspring, i.e. fullsib offspring are avoided, and by making the contributions of ancestors to offspring more equal by mating least related animals.

Returns from the utilization of genetic markers in breeding programs have been computed in two ways. In the first approach, returns accrue from additionally improved milk yield that was due to marker utilization in selection. In the second approach, changes in returns from semen sales for a breeding organization operating in a competitive market are determined. The genetic effect of markers is taken to result from preselection of young bulls. Based on the literature, the increase in mean breeding value of young bulls as a result of marker-based preselection was taken to range from .15 to .45 additive genetic standard deviation. When additive genetic standard deviation is assumed at $67 with an interest rate of 5% and a time horizon of 25 yr, cumulative discounted returns from 1 yr of marker utilization ranged from $7 to $21 per cow for progeny testing and from $20 to $60 for an open nucleus. Additional discounted financial returns from increased semen sales range from $5.0 million to $16.2 million for a situation in which an AI firm utilizes markers during 20 yr and competitors do not follow. Lower costs are expected as technology improves, and improved statistical analysis should reduce the number of typings required. Thus, utilization of markers is expected to become financially justified.