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Despite its peace process, Northern Ireland remains a deeply divided society. The legacy of a 30-year conflict has ensured that the state continues to be prone to outbreaks of violence over contentious issues such as Orange Order parading and the flying of national flags. This paper argues that in order to address this legacy, there is a need to confront the Othering processes that have helped to generate and sustain division. It will argue that programmes of adult education can play an important role in helping the conflicting groups to reimagine their ‘exclusive’ notions of the nation to one capable of incorporating the Other. [ABSTRACT FROM PUBLISHER]

Upper respiratory infection (URI) is a pervasive problem in cats and impacts the capacity and cost of sheltering programs. This study determined the pattern of respiratory pathogens in cats with and without clinical signs of URI in four different models for managing unowned cats, namely, (1) short-term animal shelters (STS), (2) long-term sanctuaries (LTS), (3) home-based foster care programs (FCP), and (4) trapneuter- return programs for community cats (TNR). Conjunctival and oropharyngeal swabs from 543 cats, approximately half of which showed clinical signs of URI, were tested for feline herpes virus-1 (FHV), feline calicivirus (FCV), Chlamydia felis, Bordetella bronchiseptica, Mycoplasma felis, and canine influenza virus by real-time PCR. FHV (59%, 41%) and B. bronchiseptica (33%, 24%) were more prevalent in both clinically affected and nonclinical cats, respectively, in STS than other management models. FCV (67%, 51%) and M. felis (84%, 86%) were more prevalent in LTS than any other management model. Clinically affected cats in FCP were more likely to carry FHV (23%, 6%), C. felis (24%, 10%), or M. felis (58%, 38%) than were nonclinical cats. Clinically affected cats in TNR were more likely to carry FCV (55%, 36%) or C. felis (23%, 4%) than were nonclinical cats. The prevalence of individual pathogens varied between different management models, but the majority of the cats in each model carried one or more respiratory pathogens regardless of clinical signs. Both confined and free-roaming cats are at risk of developing infectious respiratory disease and their health should be protected by strategic vaccination, appropriate antibiotic therapy, effective biosecurity, feline stress mitigation, and alternatives to high-density confinement. [ABSTRACT FROM AUTHOR]

Abstract: Developing countries from the southern hemisphere have similarities in terms of climatic and agricultural conditions and cattle are the most important livestock species in these countries — which leads to many areas of similar interest and opportunities regarding beef cattle production. The increase in demand for meat in developing countries offers large market opportunities for livestock producers. If the productivity of beef farmers can be improved to commercial levels, it may have the potential to address poverty in these agriculturally based economies. Climate change is predicted to be highly dynamic and can have adverse effects on crop and livestock productivity. The cattle breed to be used and the production strategy to be followed in developing countries of the southern hemisphere will depend primarily on the environment and level of management. The availability of diverse cattle breed resources with adaptive and productive differences will allow breed types to be matched to different environments, management capabilities and markets. In the harsh and undeveloped areas or pastoralist systems, pure breeding with e.g. Sanga, Zebu or naturalized breeds may be the only production strategy that can be followed. In the more developed areas, crossbreeding with small indigenous cows may succeed in improving the output of beef cattle farming. It is believed that crossbreeding will gain importance in many developing counties in the southern hemisphere. It is therefore essential that crossbreeding studies be conducted where necessary, to supply information regarding heterosis and for the development of multi-breed genetic evaluations, breeding objectives and decision making. By describing production environments it may be possible to identify genotypes that are adapted to a specific environment. However, tools are needed to overlay geo-referenced data sets onto the different environments. Statistical science continues to support animal breeding and improvement, especially with respect to production traits. Traits linked to fertility and/or survival are still problematic and the appropriate quantitative breeding technology to properly handle these traits still needs to be developed. Gene or marker assisted selection may play an important role in selection for disease and parasite resistance or tolerance, since it is generally difficult to measure these traits directly. Strategies that utilize EBVs derived from genomic analyses (genomic EBVs), together with conventional mixed model methodology, may speed up the process of breeding animals with subsequent higher and more efficient production. The application of a landscape genetics approach offers the potential to greatly enhance the knowledge of how landscape heterogeneity influences the genetic population structure, gene flow, and adaptation. Results from these studies can be used to address questions related to species management and conservation. [Copyright &y& Elsevier]

Alternative splicing is a widespread means of increasing protein diversity and regulating gene expression in eukaryotes. Much progress has been made in understanding the proteins involved in regulating alternative splicing, the sequences they bind to, and how these interactions lead to changes in splicing patterns. However, several recent studies have identified other players involved in regulating alternative splicing. A major theme emerging from these studies is that RNA secondary structures play an under appreciated role in the regulation of alternative splicing. This review provides an overview of the basic aspects of splicing regulation and highlights recent progress in understanding the role of RNA secondary structure in this process. [ABSTRACT FROM AUTHOR]

Precursor mRNA (pre-mRNA) splicing can join exons contained on either a single pre-mRNA (cis) or on separate pre-mRNA5 (trans). It is exceedingly rare to have trans-splicing between protein-coding exons and has been demonstrated for only two Drosophila genes: mod(mdg4) and lola. It has also been suggested that trans-splicing is a mechanism for the generation of chimeric RNA products con- taining sequence from multiple distant genomic sites. Because most high-throughput approaches cannot distinguish cis- and trans- splicing events, the extent to which trans-splicing occurs between protein-coding exons in any organism is unknown. Here, we used paired-end deep sequencing of mRNA to identify genes that un- dergo trans-splicing in Drosophila interspecies hybrids. We did not observe credible evidence for the existence of chimeric RNAS gen- erated by trans-splicing of RNAs transcribed from distant genomic loci. Rather, our data suggest that experimental artifacts are the source of most, if not all, apparent chimeric RNA products. We did, however, identify 80 genes that appear to undergo trans-splicing between homologous alleles and can be classified into three cate- gories based on their organization: (i) genes with multiple 3' termi- nal exons, (ii) genes with multiple first exons, and (iii) genes with very large introns, often containing other genes. Our results suggest that trans-splicing between homologous alleles occurs more com- monly in Drosophila than previously believed and may facilitate expression of architecturally complex genes. [ABSTRACT FROM AUTHOR]

Abstract: Research carried out at the Sucupira Farm of Embrapa Recursos Genéticos e Biotecnologia, in Brasilia-DF, aimed to evaluate heat tolerance in five naturalized and two exotic breeds of cattle, at different temperatures and humidity, based upon physiological and blood parameters. The data collected included heart rate (HR), rectal temperature (RT), respiratory rate (RR), and sweating rate (SR). Blood was also collected for hemogram analysis and cortisol level. The measurements were taken at 7 am and at 2 pm after the animals were exposed to the sun, with water ad libitum. This procedure was repeated for six days, three in the middle of the dry season when temperatures and humidity were lower and three at the start of the rainy season when temperatures and humidity were higher. Significant statistical differences were observed in RR and HR for day, breed and animal within breed. The analysis indicated that the Junqueira and Nellore breeds are most adapted to climatic conditions in Brasilia; while Mocho Nacional and Holstein breeds were the least adapted. Although sample size is limited, these results are important to identify which breeds are most resistant towards climatic variations observed in the Brasilia region, as well as which physiological parameters are the most indicated for use in animal breeding programs intended to select animals and breeds adapted to thermal stress conditions. [Copyright &y& Elsevier]

In a recent issue of Molecular Cell, demonstrates that, during the latest stage of the splicing reaction, the RNA-dependent helicase Prp22 is deposited upon the downstream exon, where it subsequently strips the spliced messenger RNA from the spliceosome. [Copyright &y& Elsevier]

Data from 294 045 records from a crossbred Angus × Nellore population were used to estimate fixed genetic effects (both additive and non-additive) and to test different non-additive models using ridge regression. The traits studied included weaning gain (WG), postweaning gain (PG), phenotypic scores for weaning (WC) and postweaning (PC) conformation, weaning (WP) and postweaning (PP) precocity, weaning (WM) and postweaning (PM) muscling and scrotal circumference (SC). All models were compared using the likelihood-ratio test. The model including all fixed genetic effects (breed additive and complementarity, heterosis and epistatic loss non-additive effects, both direct and maternal) was the best option to analyse this crossbred population. For the complete model, all effects were statistically significant (P < 0.01) for weaning traits, except the direct breed additive effects for WP and WM; direct complementarity effect for WP, WM, PP and PM and maternal epistatic loss for PG. Direct breed additive effect was positive for weaning traits and negative for postweaning. Maternal breed additive effect was negative for SC and WP. Direct complementarity and heterosis were positive for all traits and maternal complementarity and heterosis were also positive for all traits, except for PG. Direct and maternal epistatic loss effects were negative for all traits. We conclude that the fixed genetic effects are mostly significant. Thus, it is important to include them in the model when evaluating crossbred animals, and the model that included breed additive effects, complementarity, heterosis and epistatic loss differed significantly from all reduced models, allowing to infer that it was the best model. The model with only breed additive and heterosis was parsimonious and could be used when the structure or amount of data does not allow the use of complete model. The identification of the best crossbred sires is not an easy task as these animals are composed of distinct genetic materials from different breeds. The objective of the present study was to compare different models under ridge regression methodology to identify the best method for selecting crossbred bulls. This selection is a requisite to guide future multiracial genetic evaluations. The model that contemplated all tested effects (breed additive, complementary, heterosis and epistatic loss, both direct and maternal) proved to be the best. [ABSTRACT FROM AUTHOR]

Presents a teaser for the readers by asking them to guess the author of five short, light-hearted poems on medical students. Hints given to the readers to guess the author of the poems; 'To the Medical Students'; 'Medical Student Psychology'; 'Medical Student Metaphysics'; 'Medical Student Anthropology'; 'Medical Student Ethics'; Identity of the author.

Ribosome profiling has emerged as a powerful technique to study mRNA translation. Ribosome profiling has the potential to determine the relative quantities and locations of ribosomes on mRNA genome wide. Taking full advantage of this approach requires accurate measurement of ribosome locations. However, experimental inconsistencies often obscure the positional information encoded in ribosome profiling data. Here, we describe the Ribodeblur pipeline, a computational analysis tool that uses a maximum likelihood framework to infer ribosome positions from heterogeneous datasets. Ribodeblur is simple to install, and can be run on an average modern Mac or Linux-based laptop. We detail the process of applying the pipeline to high-coverage ribosome profiling data in yeast, and discuss important considerations for potential extension to other organisms. [ABSTRACT FROM AUTHOR]

The regulation of gene expression is critical for organismal function and is an important source of phenotypic diversity between species. Understanding the genetic and molecular mechanisms responsible for regulatory divergence is therefore expected to provide insight into evolutionary change. Using deep sequencing, we quantified total and allele-specific mRNA expression levels genome-wide in two closely related Drosophila species (D. melanogaster and D. sechellia) and their F1 hybrids. We show that 78% of expressed genes have divergent expression between species, and that cis- and trans-regulatory divergence affects 51% and 66% of expressed genes, respectively, with 35% of genes showing evidence of both. This is a relatively larger contribution of trans-regulatory divergence than was expected based on prior studies, and may result from the unique demographic history of D. sechellia. Genes with antagonistic cis- and trans-regulatory changes were more likely to be misexpressed in hybrids, consistent with the idea that such regulatory changes contribute to hybrid incompatibilities. In addition, cis-regulatory differences contributed more to divergent expression of genes that showed additive rather than nonadditive inheritance. A correlation between sequence similarity and the conservation of cis-regulatory activity was also observed that appears to be a general feature of regulatory evolution. Finally, we examined regulatory divergence that may have contributed to the evolution of a specific trait-divergent feeding behavior in D. sechellia. Overall, this study illustrates the power of mRNA sequencing for investigating regulatory evolution, provides novel insight into the evolution of gene expression in Drosophila, and reveals general trends that are likely to extend to other species. [ABSTRACT FROM AUTHOR]

Biofilms of the fungal pathogen Candida albicans include abundant long filaments called hyphae. These cells express hypha-associated genes, which specify diverse virulence functions including surface adhesins that ensure biofilm integrity. Biofilm formation, virulence, and hypha-associated gene expression all depend upon the transcription factor Efg1. This transcription factor has been characterized extensively in the C. albicans type strain SC5314 and derivatives, but only recently has its function been explored in other clinical isolates. Here we define a principal set of Efg1-responsive genes whose expression is significantly altered by an efg1Δ/Δ mutation across 17 clinical isolates. This principal gene set includes 68 direct Efg1 targets, whose 5' regions are bound by Efg1 in five clinical isolates, and 42 indirect Efg1 targets, whose 5' regions are not detectably bound by Efg1. Three direct Efg1 target genes encode transcription factors—BRG1, UME6, and WOR3 –whose increased expression in an efg1Δ/Δ mutant restores expression of multiple indirect and direct principal targets, as well as biofilm formation ability. Although BRG1 and UME6 are well known positive regulators of hypha-associated genes and biofilm formation, WOR3 is best known as an antagonist of Efg1 in the sexual mating pathway. We confirm the positive role of WOR3 in biofilm formation with the finding that a wor3Δ/Δ mutation impairs biofilm formation in vitro and in an in vivo biofilm model. Positive control of Efg1 direct target genes by other Efg1 direct target genes–BRG1, UME6, and WOR3 –may buffer principal Efg1-responsive gene expression against the impact of genetic variation in the C. albicans species. Author summary: Biofilm growth of the fungal pathogen Candida albicans is a prevalent source of infection. Biofilm gene regulation is well understood in derivatives of the type strain SC5314, but few studies have examined regulatory features in other clinical isolates. Here we characterize the phenotypic and gene regulatory impact of deletion of master regulatory gene EFG1 in seventeen clinical isolates that represent a range of clades and infection sites. The mutation abolishes biofilm formation in all isolates, but has widely variable gene expression impact, even among members of a clade. Fewer than 20% of the gene expression targets in any one isolate are principal targets, which are shared among all isolates. One principal target encodes the transcription factor Wor3, an antagonist of Efg1 in the sexual mating pathway. Our analysis shows that Wor3 has an unexpected role in which it promotes biofilm formation and the expression of principal Efg1-activated genes. [ABSTRACT FROM AUTHOR]

A central challenge of developmental and evolutionary biology is to understand the transformation of genetic information into morphology. Elucidating the connections between genes and anatomy will require model morphogenetic processes that are amenable to detailed analysis of cell/tissue behaviors and to systems-level approaches to gene regulation. The formation of the calcified endoskeleton of the sea urchin embryo is a valuable experimental system for developing such an integrated view of the genomic regulatory control of morphogenesis. A transcriptional gene regulatory network (GRN) that underlies the specification of skeletogenic cells (primary mesenchyme cells, or PMCs) has recently been elucidated. In this study, we carried out a genome-wide analysis of mRNAs encoded by effector genes in the network and uncovered transcriptional inputs into many of these genes. We used RNA-seq to identify >400 transcripts differentially expressed by PMCs during gastrulation, when these cells undergo a striking sequence of behaviors that drives skeletal morphogenesis. Our analysis expanded by almost an order of magnitude the number of known (and candidate) downstream effectors that directly mediate skeletal morphogenesis. We carried out genome-wide analysis of (1) functional targets of Ets1 and Alx1, two pivotal, early transcription factors in the PMC GRN, and (2) functional targets of MAPK signaling, a pathway that plays an essential role in PMC specification. These studies identified transcriptional inputs into >200 PMC effector genes. Our work establishes a framework for understanding the genomic regulatory control of a major morphogenetic process and has important implications for reconstructing the evolution of biomineralization in metazoans. [ABSTRACT FROM AUTHOR]

Abstract: The aim of this study was to typify competitiveness on beef cattle farms from the western border region of the state of Rio Grande do Sul, Brazil. Sixty-three farmers, each with an individual farm area exceeding 900ha, were interviewed using a semi-structured questionnaire, divided in four sections: technology (TEC), management (MAN), market relationships (MR) and institutional environment (IE). Data were analysed using Cluster and Discriminant analyses. Beef cattle producers were divided into three levels of competitiveness: low (LCL), medium (MCL) and high (HCL). Comparing LCL×MCL, the former group of farmers showed lower levels of pasture and reproduction management than the latter (subfactors within TEC). When LCL×HCL were compared, the main differences were the lower access to technological innovation and low investment with herd genetics of LCL compared with HCL. The lower level of management activities (performance recording, animal handling and calculation of financial parameters) of MCL compared with HCL were the main variables that differ between these farms. Cattle producers interviewed here were, in general, competitive, mainly due to the use of technologies on farm. However, there were limitations in the variables related to management. [Copyright &y& Elsevier]

Abstract: Studies were conducted to characterize the effect of season of the year on testicular morphology, fresh and frozen/thawed semen quality from Curraleiro (Pé-duro) bulls in the Brazilian Central west region. Five adult, healthy bulls underwent an andrological examination and semen collection using an electroejaculator, once a month for a year. Fresh and thawed semen were evaluated for progressive sperm motility and sperm vigor, sperm morphology and acrosomal integrity. Testicular length and volume were less (P <0.05) in April than in the other months of the year. For fresh semen, the ejaculate in April had less volume and sperm concentration (P <0.05), while sperm vigor was less (P <0.05) in June, increasing in January and February. With the frozen/thawed semen, the proportion of sperm was greater (P <0.05) in April to July, decreasing from October to December. Semen collected in December had the greatest (P <0.05) proportion of major defects while that collected in February/March had the highest proportion of minor defects. The proportion of live intact sperm reduced progressively from December to April/May. The marginal influence of the time of the year on testicular biometry and fresh semen in Curraleiro bulls shows the adaptation of this breed to the environmental conditions in the region. Thus, reproduction with natural mating should be successful at any time of year. For frozen semen collection for conservation programs, the best time of year is from June to September. [Copyright &y& Elsevier]

Increasing clinical evidence for the effectiveness of herbal antidepressants has led to investigations at the molecular level. Using two-dimensional gel electrophoresis, this study investigated similarities in protein expression between clomipramine, St John's wort and a Chinese herbal formula, xiaoyao-san, often used in mood disorder treatment. HT22 cells, derived from a mouse hippocampal cell line, were treated for 24 h, and protein expression was compared with that of the untreated cells (n = 4/group). Forty-three protein spots were found to be significantly differentially expressed (P < 0.05) in more than one of the treatment groups. Twenty-nine of these were identified using mass spectrometry. The most affected proteins were those involved in the cytoskeleton and energy metabolism, and an up-regulation of vimentin by all three treatments was confirmed by Western blotting. This study provides preliminary evidence for multiple common molecular targets between conventional and alternative antidepressants, which appear to collectively affect neuronal plasticity. [ABSTRACT FROM AUTHOR]

Summary: Brazilian hair sheep constitute a genetic diversity hotspot. These animals are found in the harsh environments of the Brazilian Northwest (semi‐arid) region. Genotypes (50K SNP chip) from seven Brazilian sheep breeds (five hair and two coarse wool types) and 87 worldwide breeds were used to test for population structure, admixture and genetic diversity. Moreover, phylogenetic trees evaluating migration events between genetic groups were built. Brazilian Somali, a fat‐tailed breed, had a close relationship with East African breeds and clustered distinctly from other Brazilian breeds. Brazilian Blackbelly and Barbados Blackbelly had a close relationship. The Morada Nova breed did not show close relationships with European or African breeds, revealing a single migration event from an Algerian hair breed. Brazilian Fat‐tail and Morada Nova share a common ancestor, but the former showed introgressions from Brazilian Somali and Afrikaner breeds, explaining the fat‐tail phenotype. The Santa Inês breed received a substantial contribution from Brazilian Bergamasca and showed an admixed origin with recent introgressions from other breeds, mainly from Suffolk. Furthermore, Brazilian Somali and Brazilian Fat‐tail are the most endangered sheep genetic resources in Brazil and should be the focus for ex situ conservation programs. In conclusion, Brazilian hair sheep show an African origin and are characterized by diverse genetic composition, reinforcing the need for conservation of these genetic resources, and at the same time, this highly diverse group has variability that can be used in breeding programs. [ABSTRACT FROM AUTHOR]

The aim of this study was to determine whether behavior, reproductive and health parameters could differ between sows housed individually throughout gestation (Stall) or group-housed on days 3 to 5 (Pen5) or 38 to 42 (Pen42) after insemination. After insemination, 198 sows of a same commercial farm were randomly allocated to one of three housing treatments, namely Stall, Pen5 and Pen42 systems. There was interaction between the housing system and gestation time on behavior parameters. The prevalence of active sows was higher in the Stall system than in group-housing. Stall system sows displayed marked exploratory behavior than the sows in Pen5 system. Sows in Stall system showed lower prevalence of health disorders such as vulva and body lesions and manure on the body, but higher prevalence of rectal prolapse and constipation than group-housed sows. Sows in Pen42 system showed higher rates of live piglets at birth, total piglets born and shorter gestation period than sows in Stall System. Lower number of mummified fetuses and larger number of stillbirths and stillbirths type 2, were associated to sows in Pen5 system. Sows in Pen5 system presented a reduction in health problems such as rectal prolapse and bursitis and skin inflammation as well as colds, decreased the stress level of the sows that showed greater expression of positive social behavior and decreased stereotypic behaviors, as well as maintained the reproductive parameters similar to those in individual stalls. [ABSTRACT FROM AUTHOR]

Summary: Some livestock breeds face the challenge of reduced genetic variation, increased inbreeding depression owing to genetic drift and selection. Hybridization can reverse these processes and increase levels of productivity and adaptation to various environmental stressors. Samples from American Brangus were used to evaluate the indicine/taurine composition through nine generations (~45 years) after the hybridization process was completed. The purpose was to determine how hybridization alters allelic combinations of a breed over time when genetic factors such as selection and drift are operating. Furthermore, we explored genomic regions with deviations from the expected composition from the progenitor breeds and related these regions to traits under selection. The Brangus composition deviated from the theoretical expectation, defined by the breed association, of 62.5% taurine, showing taurine composition to be 70.4 ± 0.6%. Taurine and indicine proportion were not consistent across chromosomes. Furthermore, these non‐uniform areas were found to be associated with traits that were probably under selection such as intermuscular fat and average daily gain. Interestingly, the sex chromosomes were predominantly taurine, which could be due to the composite being formed particularly in the final cross that resulted in progeny designated as purebred Brangus. This work demonstrated the process of new breed formation on a genomic level. It suggests that factors like genetic drift, selection and complementarity shift the genetic architecture into a uniquely different population. These findings are important to better understand how hybridization and crossbreeding systems shape the genetic architecture of composite populations. [ABSTRACT FROM AUTHOR]

Metabolic adaptation is linked to the ability of the opportunistic pathogen Candida albicans to colonize and cause infection in diverse host tissues. One way that C. albicans controls its metabolism is through the glucose repression pathway, where expression of alternative carbon source utilization genes is repressed in the presence of its preferred carbon source, glucose. Here we carry out genetic and gene expression studies that identify transcription factors Mig1 and Mig2 as mediators of glucose repression in C. albicans. The well-studied Mig1/2 orthologs ScMig1/2 mediate glucose repression in the yeast Saccharomyces cerevisiae; our data argue that C. albicans Mig1/2 function similarly as repressors of alternative carbon source utilization genes. However, Mig1/2 functions have several distinctive features in C. albicans. First, Mig1 and Mig2 have more co-equal roles in gene regulation than their S. cerevisiae orthologs. Second, Mig1 is regulated at the level of protein accumulation, more akin to ScMig2 than ScMig1. Third, Mig1 and Mig2 are together required for a unique aspect of C. albicans biology, the expression of several pathogenicity traits. Such Mig1/2-dependent traits include the abilities to form hyphae and biofilm, tolerance of cell wall inhibitors, and ability to damage macrophage-like cells and human endothelial cells. Finally, Mig1 is required for a puzzling feature of C. albicans biology that is not shared with S. cerevisiae: the essentiality of the Snf1 protein kinase, a central eukaryotic carbon metabolism regulator. Our results integrate Mig1 and Mig2 into the C. albicans glucose repression pathway and illuminate connections among carbon control, pathogenicity, and Snf1 essentiality. Author summary: All organisms tailor genetic programs to the available nutrients, such as sources of carbon. Here we define two key regulators of the genetic programs for carbon source utilization in the fungal pathogen Candida albicans. The two regulators have many shared roles, yet are partially specialized to control carbon acquisition and metabolism, respectively. In addition, the regulators together control traits associated with pathogenicity, an indication that carbon regulation is integrated into the pathogenicity program. Finally, the regulators help to explain a long-standing riddle—that the central carbon regulator Snf1 is essential for C. albicans viability. [ABSTRACT FROM AUTHOR]

Performance, nutrient apparent digestibility, ruminal parameters, enteric methane (CH4) emission and blood parameters were studied in sheep receiving spores of Bacillus thuringiensis (Bt) in their diet. Twenty Santa Inês lambs (10 castrated males and 10 females) with 18.0 ± 3.50 kg initial bodyweight (BW) and 3 months of age were maintained in individual stalls in a completely randomised design. They were divided into two groups with five males and five females each (Bt 2036 group (n = 10) and control group (n = 10)). The animals of the Bt 2036 group received daily 2.5 × 106 spores of Bt 2036/kg BW and control animals received a placebo. The diet consisted of Tifton-85 (Cynodon spp.) hay ad libitum and 300 g/animal.day of concentrate mixture, which was adjusted according to growth requirements. During 53 days, animal performance was evaluated, with feed intake measured three times per week and lambs weighed fortnightly. Blood samples were taken every 15 days to evaluate hematological and biochemical parameters. Rumen fermentation was investigated in three stages (start, middle and end of the experimental period) using parameters such as pH, ammoniacal nitrogen, short chain fatty acids, and populations of Fibrobacter succinogenes , Ruminococcus flavefaciens , anaerobic fungi, methanogenic archaea and protozoa. At the end of the performance experiment, 18 lambs (Bt 2036 (n = 9), control (n = 9)) were selected for a digestibility trial, and placed in metabolic cages to estimate apparent nutrient digestibility, nitrogen balance and microbial protein synthesis. Ten male (Bt 2036 (n = 5), control (n = 5)) lambs were used to evaluate CH4 production using the hexafluoride tracer technique. There was no effect (P > 0.05) of Bt 2036 on any of the evaluated parameters. The daily addition of 2.5 × 106 spores/kg BW of Bt 2036 in the ruminant diet did not cause any negative effects on hematological traits or animal poisoning, nor did it interfere with fermentation by rumen microorganisms, apparent digestibility of nutrients or animal performance. In the search for new alternatives in the treatment against gastrointestinal parasites of ruminants, Bacillus thuringiensis was highlighted by its nematicidal activity, related to the presence of toxic crystals. The rumen provides a favourable environment for the development of the microbial population and the inclusion of Bt 2036 spores in the sheep diet did not cause changes in the health of the animals. In this way, the supplementation of Bt 2036 spores, which contain toxic proteins, can be safely included in ruminant feed. [ABSTRACT FROM AUTHOR]

Genotype-phenotype relationships can vary extensively among members of a species. One cause of this variation is circuit diversification, the alteration of gene regulatory relationships among members of a species. Circuit diversification is thought to be a starting point for the circuit divergence or rewiring that occurs during speciation. How widespread is circuit diversification? Here we address this question with the fungal pathogen Candida albicans, which forms biofilms rich in distinctive hyphal cells as a prelude to infection. Our understanding of the biofilm/hyphal regulatory network comes primarily from studies of one clinical isolate, strain SC5314, and its marked derivatives. We used CRISPR-based methods to create mutations of four key biofilm transcription factor genes–BCR1, UME6, BRG1, and EFG1 –in SC5314 and four additional clinical isolates. Phenotypic analysis revealed that mutations in BCR1 or UME6 have variable impact across strains, while mutations in BRG1 or EFG1 had uniformly severe impact. Gene expression, sampled with Nanostring probes and examined comprehensively for EFG1 via RNA-Seq, indicates that regulatory relationships are highly variable among isolates. Our results suggest that genotype-phenotype relationships vary in this strain panel in part because of differences in control of BRG1 by BCR1, a hypothesis that is supported through engineered constitutive expression of BRG1. Overall, the data show that circuit diversification is the rule, not the exception, in this biofilm/hyphal regulatory network. [ABSTRACT FROM AUTHOR]

Dehorning is a common practice in cattle farming. Researchers suggest that pain during dehorning can be mitigated, although there is no conclusive evidence about the best technique and the best manner of pain relief. A systematic review-meta-analysis was performed to clarify the effect of dehorning on welfare indicators (cortisol concentration or average daily gain or vocalisation) in beef cattle up to 12 months of age. Five electronic databases were systematically searched, as well as conference proceedings and experts were contacted electronically. Pre-defined protocols were applied during all steps of the systematic review process. A random effect meta-analysis was conducted for each indicator separately with the mean of the control and treated groups. Four publications reporting seven studies and 69 trials were included in the MA involving 287 cattle. Heterogeneity between studies was observed for cortisol (I2 = 50.5%), average daily gain (I2 = 70.5%), and vocalisation (I2 = 91.9%). When comparing the non-dehorned group with amputation dehorning, the cortisol concentration was lower 30 min (P < 0.0001) and 120 min (P = 0.023) after procedure (0.767 nmol/L and 0.680 nmol/L, respectively). Local anaesthesia did not show a reduction in cortisol concentration at 30 min after dehorning by amputation. Non-dehorned animals had a tendency to decrease the number of vocalisation (P = 0.081; MD = 0.929) compared with the group dehorned by amputation. These results suggest that dehorning is a painful experience and that local anaesthesia did not alleviate short-term pain following dehorning. Further investigation into pain relief is required to improve confident decision making under practical conditions. Dehorning is a common practice in cattle farming, although it can generate a pain-induced response. Meta-analysis can provide new insights into animal welfare. Dehorned cattle showed higher cortisol concentration, whereas local anaesthesia did not reduce cortisol level and these animals tended to vocalise more. Finally, with the lack of pain-specific measures, the choice of indicators of welfare and their relationship with dehorning may be difficult. [ABSTRACT FROM AUTHOR]

There are several options in sheep genetics for production systems, since local genetic resources (generally adapted to environmental conditions) to specialized breeds. Crossbreeding is an alternative to explore heterosis and complementarity between breeds. This study evaluated eight genetic groups from crossbreding between Santa Inês (SI), Poll Dorset (PD), Dorper (DO), East Friesian (EF), Primera (PR), and White Dorper (WD). SI and PD were used as maternal and paternal breed, while the others were used only as sires. Forty-eight male lambs were evaluated for withers height, thoracic perimeter, body and back length and skin thickness, as well as cold carcass weight and weights of commercial cuts such as neck, belly, shoulder, leg, rib and loin. Santa Inês took more time to reach the designated slaughter weight (30kg) than Dorper and Poll Dorset crosses. 87PDSI, 75PDSI and DOPD showed higher commercial cut weights and carcass yield. The use of Santa Inês, a locally-adapted hair breed, as maternal breed in crossbreeding system showed similar results to use of Poll Dorset, a meat specialized breed. These results highlight the usefulness of a local genetic resource in intensive system. Poll Dorset are recommended as sires for crossing with Santa Inês dams in intensive lamb rearing systems. [ABSTRACT FROM AUTHOR]

The aim of the present study was to evaluate biometric measures of Crioula Lageana cattle breed at different ages, to establish patterns of variation of these measures, contributing to the phenotypic characterization of the breed. Body measurements (body length, shoulder height, thoracic perimeter, rump height, rump width and rump length) were collected from 346 animals from three different regions of the Santa Catarina State Plateau (Campos de Curitibanos, Coxilha Rica and Campos de Caçador). The biometric measurements were evaluated in relation to age, gender and region of origin. Statistical analysis was performed using SAS version 9.3. The procedures used included analysis of variance, correlations, cluster, discriminant and canonical analysis. Statistical difference between males and females was observed for all measurements, except rump height, demonstrating sexual dimorphism. Rump height varied up to 3 and 5 years of age and body length varied in animals over 11 years of age; while rump width and thoracic perimeter varied up to 7 and 9 years of age. On average, 50% of the animals were classified correctly, indicating little difference between regions for biometric traits. Also, animals from Campos de Curitibanos were those with greater distance from the other two regions of the Santa Catarina plateau. Correlations between shoulder height, rump width and length were above 0.80. So, rump length could be considered the measurement best suited for assessment of body size of this breed due to the high correlation with the other measures and the easy way to assess this parameter. [ABSTRACT FROM AUTHOR]

Summary: This study consisted of two experiments with the following objectives: to evaluate the effects of tannins from the tropical legume macrotiloma (Macrotyloma axillare) on total gas and methane (CH4) production, as well as on ruminal fermentation parameters by performing an in vitro bioassay, with samples incubated with and without polyethylene glycol (PEG) in a semi‐automatic system; and secondly in a 17 day in vivo experiment, to determine apparent total tract digestibility (ATTD) of dietary nutrients and ruminal fermentation parameters of 12 intact 8‐ to 9‐month‐old Santa Inês (averaging 24.95 ± 1.8 kg body weight) ewes fed tropical grass hay supplemented with macrotiloma hay. The ewes were divided into two treatment groups depending on their diet: chopped aruana grass hay (Panicum maximum cv. Aruana) (control—CON); and aruana grass hay supplemented with chopped macrotiloma hay (macrotiloma—MAC). The animals were kept for 5 consecutive days in metabolic cages for the ATTD assay, and at the end of this period, samples of rumen fluid were collected from each ewe to determine ammoniacal nitrogen (NH3‐N) and short‐chain fatty acid (SCFA) production, and protozoa count. For the in vitro assay, a decrease in total gas and CH4 production was observed for samples incubated without PEG (p < .05). No differences were observed for the other parameters evaluated (p > .05). In the in vivo experiment, increased intake and ATTD of crude protein were observed for the animals fed MAC when compared to CON (p < .05). For rumen fermentation parameters, increased NH3‐N, total SCFA and isobutyrate concentrations, as well as reduced protozoa count were observed for MAC when compared to CON (p < .05). The results observed here indicated the potential of macrotiloma for use as a ruminant feed, and antimethanogenic potential of this plant was noted. [ABSTRACT FROM AUTHOR]

The objective of this study was to predict the economic values for production, functional and fertility traits, as well as to rank them in order of economic importance for milk production systems in southern Brazil. For this, two clusters were formed according to their production and the characteristics considered were: milk production (MP), lactation persistency (LP), milk fat (FAT), milk protein (PROT), somatic cell count (SCC), age at first calving (AFC), calving interval (CI), feed intake (Intake), mortality (MORT) and cow weight (CW). Revenue was based on the sale of milk, surplus heifers and cull cows and the actual operating costs were used to calculate profit and gross margin. The profit function used to calculate the economic values was based on a 100-cow farm. The average economic values of the characteristics that affect the profit of the producer were in order: FAT: US $ 3,776.07; PROT: US $ 1,888.03; MP US $ 1,258.69, LP: US $ 1,258.69; CW: US $ 124.03; MORT: US $ -14.30; Intake: US $ -614.01; CI: US $ -1,023.62; AFC: US $ -2,724.29; SCC: US $ -3,146.87. Therefore, the economic values calculated for the volume of milk, fertility, milk quality, disease resistance and feed intake addressed that the use of these traits as selection objectives in breeding programmes should result in an increased profitability for the farmer. [ABSTRACT FROM AUTHOR]

Strategies for the sustainable intensification of ruminant production suggest breeding animals adapted to the environment in which they live using local fodders to maximize efficient ruminal fermentation. The purpose of this study was to explore the effects of using Orbignya phalerata (Babassu) and Combretum leprosum (Mofumbo) leaves in ruminal short chain fatty acids (SCFA) and microbial community, as well as finishing performance, carcass characteristics and meat fatty acid profile of Santa Inês hair lambs. The experimental treatments were diets with 50:50 forage:concentrate ratios, using the leaves of the experimental plants as a 33 g/100 g of dry matter (DM) replacement of Cynodon dactylon (Tifton-85) hay, with three groups: Control (no hay replacement), Babassu and Mofumbo. Twenty-four Santa Inês lambs (body weight = 20.0 ± 5.2 kg) were used in a randomized experimental design with eight repetitions (5 males and 3 female) per treatment. Ruminal fluid samples of each animal were collected to determine SCFA and microbial community. The male animals were evaluated for finishing performance and carcass characteristics while longissimus lumborum muscle samples were used for determination of fatty acid profile. Interaction between treatment and sex was observed for total SCFA ( P < 0.05). Treatment affected ( P < 0.05) propionate, isobutyric, isovaleric and valeric fatty acids. Mofumbo showed a greater relative abundance of rumen fungi and Ruminococcus flavefaciens , and lower Archaea. There was no difference between treatments ( P > 0.05) for finishing performance and carcass characteristics but meat fatty acid characteristics were affected by treatments. A redundancy analysis based on microbial abundance profile demonstrated two clusters, one cluster with Babassu and Control treatments, and other cluster with Mofumbo, with some variables associated to dissimilarity between clusters. These results indicated that the inclusion of these plants in lamb diets affects ruminal short chain fatty acids and microbial population, without compromising the production potential, carcass characteristics and meat fatty acid profile. [ABSTRACT FROM AUTHOR]

Data from 5689 lactating cows in 35 different dairy herds in Southern Brazil were evaluated over a 15-year period to examine the influence of meteorological variables on milk production in dairy cows with primiparous (1st) and multiparous (2nd to 4th) lactation. Meteorological variables considered were maximum and minimum temperature, relative humidity of air, solar radiation, wind speed, precipitation and temperature and humidity index corrected for solar radiation and wind speed (THIc). Data were submitted to principal component analysis (PRINCOMP), Pearson correlation (CORR) and step-by-step (STEPDISC) discriminant analyses, using the Statistical Analysis System (SAS®). Primiparous and multiparous cows were negatively affected by maximum temperature in summer, while the higher the minimum temperature in winter was, the better the milk production was. Primiparous cows produced, on average, 28.17 kg/day of milk and were 26.15 months old while the multiparous cows in average produced 30.76 kg/day and were 54.47 months old. The greatest average maximum temperature recorded during the 15 years of observations did not exceed 30°C and the THI corrected were maintained within acceptable values for animal thermal comfort. Lactation order and milk production showed a negative and significant correlation with minimum temperature, but with low magnitude. Milk production of multiparous cows was negatively affected by maximum temperature in summer and milk production of both categories were affected negatively by minimum temperature in fall. The principal component analysis did not show any association between milk production, lactation order and meteorological variables. Discriminant analysis presented significant values for meteorological variables, but with very low values of partial R2 estimated. Meteorological variables in a Cfb climatic zone did not negatively affect milk production in primiparous and multiparous lactating cows. [ABSTRACT FROM AUTHOR]

In this study, the possibility of using Babassu ( Orbignya phalerata) and Mofumbo ( Combretum leprosum) leaves for lambs feed was verified. Performance, biochemical and haematological parameters, microbial protein synthesis, nutrient apparent digestibility and enteric production of methane ( CH4) were evaluated. The experimental treatments included diets with forage-to-concentrate ratios of 50:50, with the leaves of the experimental plants replacing 33% of the Cynodon dactylon (Tifton-85) hay with three treatments: control (no hay replacement) and substitution with Babassu or Mofumbo. For the performance study, 24 Santa Inês lambs were used, in a randomized experimental design with eight repetitions (5 male and 3 female) for each treatment and 48 days of experimental trial. After this period, for nine days, six animals from each treatment were allocated in metabolic cages to determine the apparent nutrient digestibility, microbial protein synthesis and nitrogen balance. Simultaneously, enteric CH4 was measured in vivo. The control group showed higher (p < 0.05) apparent digestibility of acid detergent fibre. Enteric CH4 production of lambs fed Mofumbo leaves did not differ from that of the control group, but was lower (p < 0.05) than in those fed with Babassu. The inclusion of Babassu and Mofumbo leaves showed no negative effects on animal health and did not compromise performance. Mofumbo also presented CH4 mitigating potential, indicating that those plants can be used as ingredients in the composition of lamb diets with the advantage of reducing methane production. [ABSTRACT FROM AUTHOR]

The aim of this study was to evaluate the effects of concentrate supplementation on the performance and ingestive behaviour of lambs grazing tropical grasslands of Panicum maximum cv. IZ-5 and its effect on pasture characteristics. Different levels of daily supplementation with concentrate were compared: no supplementation; or supplemented at 1.5% and 2.5% of lamb liveweight. The grazing simulation technique was used for qualitative assessment of the pasture every 28 days. Herbage mass, pasture growth rate, sward height as well as botanical and morphological composition of the pasture were evaluated. Average daily gain, gain per hectare and ingestive behaviour were measured on the lambs. The forage supply was 4% of green leaves (4 kg dry matter per 100 kg of liveweight) in all treatments. Six 3-4-month-old Texel and Corriedale lambs were used per paddock. The design was a randomised block design with three replications. Concentrate supplementation had a direct effect on pasture structure, especially height (significant interaction treatment vs period - P = 0.0373). In the treatment without supplementation, the animals grazed for a longer period than the others. Idle time was higher in the treatment with the highest level of supplementation, and rumination time was similar among the treatments. Supplementation with 2.5% significantly increased the average daily gain (0.143 g vs 0.026 g for no supplementation) and gain per hectare (30 kg vs 258 kg for no supplementation vs supplementation at 2.5% of lamb liveweight, respectively). The results show the potential increase in production and productivity with the use of concentrate supplementation at 2.5% lamb bodyweight. Notwithstanding the increase in production, supplementation with concentrate provided a strong negative impact on pasture structure and behaviour of animals that should be considered when using concentrate supplementation for finishing lambs in tropical regions. [ABSTRACT FROM AUTHOR]

Growth curves were determined for four breeds of Brazilian locally adapted swine (Moura, Piau, Nilo and Monteiro) using nonlinear models. Data was collected on 13 morphological measurements of 220 animals of both sexes from 30 days of age to adult stages. Curves were fitted using nonlinear regression equations (Gompertz, Weibull, Logistic, Brody, Von Bertalanffy and Richards). The best curve was selected by the highest R² and lowest root mean squared error. The Weibull function was the most suitable for all breeds and genders. In general, females reached their adult size earlier, but males were larger. On the one hand, the Moura breed is the most similar to industrial breeds one, possibly because it is reared in fattening systems. On the other hand, the Monteiro breed was a later-developing one. Brazilian pig breeds have different growth patterns, associated with the genetic origin of the breed and its adaptations to environment. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the heat tolerance of five zebu breeds using physical, physiological and hematological traits as well as thermographic responses. Forty cows of the Gir, Girolando, Nelore, Sindhi and Indubrasil breeds (eight cows each), approximately three years of age, were evaluated. Body weight, withers and hump heights as well as thoracic circumference were recorded. The density and length of the hair was obtained by collecting one square centimeter in the rump region and skin color using the CIELAB system. Rectal temperature, heart and respiratory rates were evaluated during the morning at 4:30 h, and in the afternoon, at 14:30 h, with six repetitions. Blood samples were collected for hematological evaluation. The surface temperature was obtained using an infrared camera FLIR ® T400. Two images were taken from each animal, one laterally of the whole body and the other of the head region. Air temperature, wind speed, relative humidity were obtained from a mobile weather station. The statistics analysis included an analyzes of variance, principal factors, as well as cluster, discriminant and canonical analyzes, logistic regression and calculation of odds ratio. There were significant differences in the rectal temperature, heart and respiratory rates between breeds. Gir and Indubrasil breeds had the highest rectal temperatures. Breed was significant for surface temperatures and showed that physical and physiological factors affected breeds in different ways. Eye and brain surface temperatures were the most affected by environmental parameters. Also, environmental parameters affected packed cell volume and red cell number. Odds ratio test showed that the Gir breed was three times more likely to have higher rectal temperature compared with Sindhi as confirmed by the logistic regression. When the black globe temperature approached 35 °C, the probability of the Gir animals having rectal temperatures above normal was approximately 70%. Gir was the breed least adapted to climate conditions of the experiment while the Sindhi and Girolando breeds showed the best physiological response to thermal stress. [ABSTRACT FROM AUTHOR]

Live fish movement is considered as having an important role in the transmission of infectious diseases. For that reason, interventions for cost-effective disease prevention and control rely on a sound understanding of the patterns of live fish movements in a region or country. Here, we characterize the network of live fish movements in the Irish salmonid farming industry during 2013, using social network analysis and spatial epidemiology methods, and identify interventions to limit the risk of disease introduction and spread. In the network there were 62 sites sending and/or receiving fish, with a total of 130 shipments (84 arcs) comprising approx. 17.2 million fish during the year. Atlantic salmon shipments covered longer distances than trout shipments, with some traversing the entire country. The average shipment of Atlantic salmon was 146,186 (SD 194,344) fish, compared to 77,928 (127,009) for trout, however, variability was high. There were 3 periods where shipments peaked (February–April, June–September, and November), which were related to specific stages of fish. The network was disconnected and had two major weak components, the first one with 39 nodes (mostly Atlantic salmon sites), and the second one with 10 nodes (exclusively trout sites). Correlation between in and out-degree at each site and assortativity coefficient were slightly low and non-significant: −0.08 (95% CI: −0.22, 0.06) and −0.13 (95% CI: −0.36, 0.08), respectively, indicating random mixing with regard to node degree. Although competing models also produced a good fit to degree distribution, it is likely that the network possesses both small-world and scale-free topology. This would facilitate the spread and persistence of infection in the salmon production system, but would also facilitate the design of risk-based surveillance strategies by targeting hubs, bridges or cut-points. Using Infomap community detection algorithms, 2 major communities were identified within the giant weak component, which were linked by only 4 nodes. Communities found had no correspondence with geographical zones within the country, which could potentially hinder the implementation of zoning strategies for disease control and eradication. Three significant spatial clusters of node centrality measures were detected, two in county Donegal (betweenness and outcloseness) and one in county Galway (incloseness), highlighting the importance of these locations as hot spots of highly central sites with a higher potential for both introduction and spread of infection. These results will assist in the design and implementation of measures to reduce the sanitary risks emerging from live fish trade within Ireland. [ABSTRACT FROM AUTHOR]

Heat is a major factor limiting the production of animals in the tropics. Sheep are well adapted to diverse ecosystems, however, temperature and relative humidity can influence animal husbandry. Therefore, this study was carried out to verify the thermoregulation in rams of six breeds (Bergamasca, Dorper, Ile de France, Hampshire Down, Santa Ines and Texel) through the evaluation of physiological traits, body measures, laser and thermographic infrared temperatures as well as testicle morphometry associated with heat tolerance. Animals were measured and weighed, coat and hair colour determined, as well as physiological traits and laser and thermographic infrared temperatures measured twice a day. Data were analyzed with the Statistical Analysis System ® . There were differences among breeds for most of the traits linked to heat tolerance, with the Santa Ines showing better adaptation to heat stress compared to other breeds. The Dorper was not significantly better than Bergamasca or Hampshire Down breeds, while Texel and Ile de France were less well adapted. Scrotal temperatures were lowest in Hampshire Down and Dorper, while highest in Texel. Temperature gradient measured by thermography identified Hampshire Down as the least heat tolerant breed. Traits linked to heat tolerance should be taken into consideration when choosing breeds for lamb production in tropical regions. [ABSTRACT FROM AUTHOR]

To evaluate the effect of heat stress on sperm characteristics, as well as testicular biometrics and heat radiation, six breeds of rams: two Brazilian locally adapted breeds (Santa Ines and Bergamasca) and four exotic breeds (Dorper, Texel, Ile de France, and Hampshire Down) underwent scrotal insulation. The experiment consisted of pre-scrotal insulation (week −1), insulation (week 0), and post-insulation (week 1–11) phases. Insulation changed the scrotum and testicular measurements, the heat radiated from the gonads caused deleterious effects, both on the process of spermatogenesis and sperm maturation in the epididymis. However, all the characteristics studied showed reversibility at 11 weeks post-insulation, showing the ability of the seminiferous epithelium to react to the effects of environmental factors. The locally, adapted breeds were more resistant than exotic to testicular heat stress. [ABSTRACT FROM AUTHOR]

The aim of this work was to evaluate the growth performance, carcass characteristics, 12th rib tissue composition, haematological and serum biochemical parameters, as well as the presence of gossypol residues in the meat of Santa Inês lambs fed cotton crop by-products. For an experimental period of 90 days, 24 intact male Santa Inês lambs (bodyweight (BW): 20.6 ± 1.9 kg; 4 months old) were fed a 50: 50 forage : concentrate diets fed ad libitum. Chopped Coast cross (Cynodon dactylon (L.) Pers) hay was used as forage. The animals were then allocated into four treatments, according to the cotton crop by-product included in the concentrate formulation: Control (CON) -- No cotton crop by-product used in formulation; Whole cottonseed (WCS); Cottonseed cake (CSC); and Cottonseed meal (CSM). The animals were weighed and blood collected every 15 days. At the end of the experimental period, the lambs were slaughtered and the evaluations of carcass characteristics, 12th rib tissue composition and presence of gossypol residues in the meat were carried out. Dry matter intake was higher (P < 0.05) for the diets containing cotton crop by-products, but BW gains were not different (P > 0.05). Despite these results the animals fed the highest level of gossypol (WCS) had lower (P < 0.05) carcass yield resulting in lower (P < 0.05) carcass weight, suggesting a possible negative effect of gossypol on carcass development. Serum urea was elevated on all treatments including CON, otherwise haematological and biochemical parameters were within reference ranges. No gossypol residues in meat were detected by the method used here, which had a minimum detection limit of 20 ppb. It is concluded that the cotton crop by-products may have impaired carcass production but did not leave gossypol residues in lamb meat. [ABSTRACT FROM AUTHOR]

Pedigree information available for Angus (ANG), Devon (DEV), Hereford (HER), and Shorthorn (SHO) cattle in Brazil was analyzed to appraise the genetic diversity and population structure of these breeds. Pedigree records collected from the beginning of the 20th century until 2010 were used in the analyses. Over time, the number of herdbook registrations declined in HER after a peak in the 1970s, remained low in DEV and SHO, and increased steadily in ANG since the 1990s, such that it the latter is now the leading British cattle breed in Brazil. The average number of offspring registered per sire ranged from about 12 (SHO) to 20 (DEV) and the mean generation interval ranged from about 6.0 (HER and SHO) to 6.4 (ANG) years. In the reference population (calves born in 2009 and 2010, plus those born in 2008 for SHO) the mean equivalent number of generations known ranged from about 7 (SHO) to 9 (HER). In the 4 breeds studied, nearly all animals born over the last few years are inbred, even though the mean level of inbreeding in the reference population is below 4% in all breeds. The rate of inbreeding per generation, computed from the individual increase in inbreeding, ranged from about 0.2 (ANG) to 0.5% (DEV), with a corresponding effective population size of 245 and 92, respectively, which is above the recommended minimum critical threshold. The number of founders/ancestors contributing with 50% of the reference population gene pool was 211/26 for ANG, 41/14 for DEV, 164/25 for HER, and 79/10 for SHO, with effective number of founders/ancestors/ founder genomes of 470/68/36, 89/33/16, 289/59/30, and 200/28/18 for ANG, DEV, HER, and SHO, respectively. The genetic contribution of different countries to the gene pool of each breed indicated that, throughout the period studied, DEV genes originated predominantly from the United Kingdom, while for the other breeds there was a changing pattern over time. Until the 1970s Argentina was the major supplier of ANG, while HER and SHO genes were mostly from Uruguay, but since then the United States took the leading role as supplier of ANG, HER, and SHO genes to Brazil. Our results reveal a mild increase in inbreeding in all breeds studied, with effective population size estimates indicating that reasonable levels of genetic diversity have been maintained in all 4 breeds. Continuous monitoring of inbreeding trends and of parameters derived from probability of gene origin should be ensured to warrant the long-term maintenance of genetic diversity. [ABSTRACT FROM AUTHOR]

Contents This study investigates the association of semen traits with boar fertility. The fertility outcome (farrowing rate - FR and total piglets born - TB) of 14 boars was obtained from a field trial conducted during 10 week of breeding period on a commercial farm using multiparous sows (n = 948) through single-sire mating with 2 × 109 motile sperm cells per artificial insemination (AI) dose. Sperm motion parameters, evaluated with computer-assisted semen analysis system in raw and stored semen at 17°C for 240 h, in addition to morphological sperm defects, measured on the collection day, were included in the analysis to determine which semen traits were important to discriminate the fertility potential of ejaculates from these boars. The data underwent multivariate cluster, canonical and discriminant analyses. Four clusters of boars were formed based on fertility outcome. One boar, with the lowest FR and TB values (89.7% and 11.98), and two boars, with the highest FR and TB values (97.8% and 14.16), were placed in different clusters. The other boars were separated in two distinct clusters (four and seven boars), including boars with intermediate TB (12.64 and 13.22) but divergent values for FR (95.9% vs 91.8%). Semen traits with higher discriminatory power included total motility, progressive motility, amplitude of lateral head displacement and cytoplasmatic droplets. Through multivariate discriminant analysis, more than 80% of the 140 ejaculates were correctly classified into their own group, showing that this analysis may be an efficient statistical tool to improve the discrimination of potential fertility of boars. Nevertheless, the validation of the relationship between fertility and semen traits using this statistical approach needs to be performed on a larger number of farms and with a greater number of boars. [ABSTRACT FROM AUTHOR]