Genomic prediction for tick resistance in Braford and Hereford cattle.

One of the main animal health problems in tropical and subtropical cattle production is the bovine tick, which causes decreased performance, hide devaluation, increased production costs with acaricide treatments, and transmission of infectious diseases. This study investigated the utility of genomic prediction as a tool to select Braford (BO) and Hereford (HH) cattle resistant to ticks. The accuracy and bias of different methods for direct and blended genomic prediction was assessed using 10,673 tick counts obtained from 3,435 BO and 928 HH cattle belonging to the Delta G Connection breeding program. A subset of 2,803 BO and 652 HH samples were genotyped and 41,045 markers remained after quality control. Log transformed records were adjusted by a pedigree repeatability model to estimate variance components, genetic parameters, and breeding values (EBV) and subsequently used to obtain deregressed EBV. Estimated heritability and repeatability for tick counts were 0.19 ± 0.03 and 0.29 ± 0.01, respectively. Data were split into 5 subsets using k-means and random clustering for cross-validation of genomic predictions. Depending on the method, direct genomic value (DGV) prediction accuracies ranged from 0.35 with Bayes least absolute shrinkage and selection operator (LASSO) to 0.39 with BayesB for k-means clustering and between 0.42 with BayesLASSO and 0.45 with BayesC for random clustering. All genomic methods were superior to pedigree BLUP (PBLUP) accuracies of 0.26 for k-means and 0.29 for random groups, with highest accuracy gains obtained with BayesB (39%) for k-means and BayesC (55%) for random groups. Blending of historical phenotypic and pedigree information by different methods further increased DGV accuracies by values between 0.03 and 0.05 for direct prediction methods. However, highest accuracy was observed with single-step genomic BLUP with values of 0.48 for -means and 0.56, which represent, respectively, 84 and 93% improvement over PBLUP. Observed random clustering cross-validation breed-specific accuracies ranged between 0.29 and 0.36 for HH and between 0.55 and 0.61 for BO, depending on the blending method. These moderately high values for BO demonstrate that genomic predictions could be used as a practical tool to improve genetic resistance to ticks and in the development of resistant lines of this breed. For HH, accuracies are still in the low to moderate side and this breed training population needs to be increased before genomic selection could be reliably applied to improve tick resistance.

A genome-wide scan for selection signatures in Nellore cattle.

Brazilian Nellore cattle (Bos indicus) have been selected for growth traits for over more than four decades. In recent years, reproductive and meat quality traits have become more important because of increasing consumption, exports and consumer demand. The identification of genome regions altered by artificial selection can potentially permit a better understanding of the biology of specific phenotypes that are useful for the development of tools designed to increase selection efficiency. Therefore, the aims of this study were to detect evidence of recent selection signatures in Nellore cattle using extended haplotype homozygosity methodology and BovineHD marker genotypes (>777,000 single nucleotide polymorphisms) as well as to identify corresponding genes underlying these signals. Thirty-one significant regions (P < 0.0001) of possible recent selection signatures were detected, and 19 of these overlapped quantitative trait loci related to reproductive traits, growth, feed efficiency, meat quality, fatty acid profiles and immunity. In addition, 545 genes were identified in regions harboring selection signatures. Within this group, 58 genes were associated with growth, muscle and adipose tissue metabolism, reproductive traits or the immune system. Using relative extended haplotype homozygosity to analyze high-density single nucleotide polymorphism marker data allowed for the identification of regions potentially under artificial selection pressure in the Nellore genome, which might be used to better understand autozygosity and the effects of selection on the Nellore genome.

Genome scan for meat quality traits in Nelore beef cattle.

Meat quality traits are economically important because they affect consumers' acceptance, which, in turn, influences the demand for beef. However, selection to improve meat quality is limited by the small numbers of animals on which meat tenderness can be evaluated due to the cost of performing shear force analysis and the resultant damage to the carcass. Genome wide-association studies for Warner-Bratzler shear force measured at different times of meat aging, backfat thickness, ribeye muscle area, scanning parameters [lightness, redness (a*), and yellowness] to ascertain color characteristics of meat and fat, water-holding capacity, cooking loss (CL), and muscle pH were conducted using genotype data from the Illumina BovineHD BeadChip array to identify quantitative trait loci (QTL) in all phenotyped Nelore cattle. Phenotype count for these animals ranged from 430 to 536 across traits. Meat quality traits in Nelore are controlled by numerous QTL of small effect, except for a small number of large-effect QTL identified for a*fat, CL, and pH. Genomic regions harboring these QTL and the pathways in which the genes from these regions act appear to differ from those identified in taurine cattle for meat quality traits. These results will guide future QTL mapping studies and the development of models for the prediction of genetic merit to implement genomic selection for meat quality in Nelore cattle.

Saturated fat-rich diet increases fetal lipids and modulates LPL and leptin receptor expression in rat placentas.

Metabolic alterations in obese and overweight mothers impact the placenta and the fetus, leading to anomalies in fetal growth and lipid accretion. The primary aim of the study was to examine the effect of a saturated fat-rich diet (FD) on growth, lipid accretion, and lipases, leptin and leptin receptor (ObR) expression in the placenta and fetal liver. We also aimed to find a role for fetal leptin in the modulation of placental and fetal liver lipase and ObR expression. Six-week-old rats were fed with a standard rat chow (control) or a 25% FD for 7 weeks until mating and during pregnancy. Also, in a group of control rats, fetuses were injected with leptin on days 19, 20, and 21 of pregnancy. On day 21, we assessed lipidemia, insulinemia, and leptinemia in mothers and fetuses. In the placenta and fetal liver, lipid concentration was assessed by thin layer chromatography (TLC) and the gene expression of lipoprotein lipase (LPL), endothelial lipase, insulin receptor (Insr), leptin, and ObR by RT-PCR. The FD induced hypertriglyceridemia and hyperleptinemia (P<0.01) in mothers and fetuses, an increase in maternal (P<0.05) and fetal weight (P<0.01), overaccumulation of lipids in fetal liver (P<0.01), and enhanced leptin expression in the placenta and fetal liver (P<0.05). Placental expression of IR and LPL was increased (P<0.05), and ObR decreased (P<0.05) in the FD group. Fetal administration of leptin induced the placental and fetal liver downregulation of ObR (P<0.05) and upregulation of LPL expression (P<0.05). The FD led to increased fetal lipid levels, which may result from high maternal lipid availability and fetal leptin effects.

Intrauterine effects of impaired lipid homeostasis in pregnancy diseases.

Lipids are crucial structural and bioactive components that sustain embryo, fetal and placental development and growth. Intrauterine development can be disturbed by several diseases that impair maternal lipid homeostasis and lead to abnormal lipid concentrations in the fetal circulation. Deficiency in essential fatty acids can lead to congenital malformations and visual and cognitive problems in the newborn. Either deficient mother-to-fetus lipid transfer or abnormal maternal- fetal lipid metabolism can cause fetal growth restriction. On the other hand, excessive mother-to-fetus fatty acid transfer can induce fetal overgrowth and lipid overacummulation in different fetal organs and tissues. The placenta plays a fundamental role in the transfer of lipid moieties to the fetal compartment and is affected by maternal diseases associated with impaired lipid homeostasis. Postnatal consequences may be evident in the neonatal period or later in life. Indeed, both defects and excess of different lipid species can lead to the intrauterine programming of metabolic and cardiovascular diseases in the offspring. This review summarizes the lipid impairments induced by different pathologies, including placental insufficiency, malnutrition, obesity and diabetes, and their consequent developmental defects.

Adverse periocular reactions to five types of prostaglandin analogs.

PURPOSE: We investigated the appearance frequency of eyelid pigmentation and eyelash bristles after the use of five types of prostaglandin (PG) analogs. METHODS: This study included 250 eyes from 250 patients diagnosed with primary open-angle glaucoma or ocular hypertension who were treated with either latanoprost, travoprost, tafluprost, bimatoprost, or isopropyl unoprostone for >3 months in only one eye. Photographs of both eyes were obtained, and the images were assessed by three ophthalmologists who were masked to treatment type. The existence of eyelid pigmentation and eyelash bristles was judged, and images of the left and right eyes were compared. Subjective symptoms regarding the existence of eyelid pigmentation and eyelash bristles were investigated through a questionnaire. RESULTS: There was no significant difference between the five types of medications with regard to eyelid pigmentation (P=0.537). Use of isopropyl unoprostone resulted in a significantly lower incidence of eyelash bristles (P<0.0001). The questionnaire investigation showed that eyelid pigmentation and eyelash bristles were significantly more frequent with travoprost (42.0% and 42.0%, respectively) and bimatoprost (58.0% and 60.0%, respectively) than with other three medications (P<0.0001). CONCLUSION: The appearance frequency of eyelid pigmentation was similar among the five types of PG analogs studied, and eyelash bristles appeared less frequently with isopropyl unoprostone use. Patients are conscious of eyelash bristles; therefore, these adverse effects should be sufficiently explained to patients before PG administration.

Folic acid and safflower oil supplementation interacts and protects embryos from maternal diabetes-induced damage.

Maternal diabetes increases the risk of embryo malformations. Folic acid and safflower oil supplementations have been shown to reduce embryo malformations in experimental models of diabetes. In this study we here tested whether folic acid and safflower oil supplementations interact to prevent embryo malformations in diabetic rats, and analyzed whether they act through the regulation of matrix metalloproteinases (MMPs), their endogenous inhibitors (TIMPs), and nitric oxide (NO) and reactive oxygen species production. Diabetes was induced by streptozotocin administration prior to mating. From Day 0.5 of pregnancy, rats did or did not receive folic acid (15 mg/kg) and/or a 6% safflower oil-supplemented diet. Embryos and decidua were explanted on Day 10.5 of gestation for further analysis of embryo resorptions and malformations, MMP-2 and MMP-9 activities, TIMP-1 and TIMP-2 levels, NO production and lipid peroxidation. Maternal diabetes induced resorptions and malformations that were prevented by folic acid and safflower oil supplementation. MMP-2 and MMP-9 activities were increased in embryos and decidua from diabetic rats and decreased with safflower oil and folic acid supplementations. In diabetic animals, the embryonic and decidual TIMPs were increased mainly with safflower oil supplementation in decidua and with folic acid in embryos. NO overproduction was decreased in decidua from diabetic rats treated with folic acid alone and in combination with safflower oil. These treatments also prevented increases in embryonic and decidual lipid peroxidation. In conclusion, folic acid and safflower oil supplementations interact and protect the embryos from diabetes-induced damage through several pathways related to a decrease in pro-inflammatory mediators.

Dietary treatments enriched in olive and safflower oils regulate seric and placental matrix metalloproteinases in maternal diabetes.

OBJECTIVES: Matrix metalloproteinases (MMPs) are proteolytic enzymes involved in placental development and function, although related to the pro-inflammatory environment when produced in excess. Previous studies have identified MMP-2 and MMP-9 overactivities in the placenta from diabetic rats. In this study, we aimed to determine whether diets supplemented with olive and safflower oil, enriched in natural PPAR ligands, are able to regulate MMP-2 and MMP-9 activities in the placenta and serum from diabetic rats. STUDY DESIGN: Diabetes was induced in rat neonates by streptozotocin administration (90mg/kg s.c.). Control and diabetic rats were fed with 6% olive oil- or 6% safflower oil-supplemented diets from days 0.5-13.5 of gestation. MAIN OUTCOME MEASURES: On day 13.5 of gestation, placentas and sera were isolated for further determination of matrix metalloproteinases (MMPs) 2 and 9 activities by zymography. Placental MMP-2 and MMP-9 protein concentration and immunolocalization were also determined. RESULTS: Sera from diabetic pregnant animals showed MMP-2 and MMP-9 overactivities when compared to controls. Serum MMP-9 activity was significantly decreased when the diabetic animals received the olive and safflower oil dietary treatments. Placentas from diabetic rats showed increased MMP-2 and MMP-9 activities and protein concentrations, and both were decreased when diabetic rats received the olive and safflower dietary treatments. CONCLUSIONS: This study demonstrates that both olive and safflower oil-supplemented diets were able to prevent MMPs overactivities in the placenta from diabetic rats, and that these beneficial effects are reflected in rat sera.

Safflower and olive oil dietary treatments rescue aberrant embryonic arachidonic acid and nitric oxide metabolism and prevent diabetic embryopathy in rats.

Aberrant arachidonic acid and nitric oxide (NO) metabolic pathways are involved in diabetic embryopathy. Previous works have found diminished concentrations of PGE(2) and PGI(2) in embryos from diabetic rats, and that PGI(2) is capable of increasing embryonic PGE(2) concentrations through the activation of the nuclear receptor PPARdelta. PPARdelta activators are lipid molecules such as oleic and linoleic acids, present in high concentrations in olive and safflower oils, respectively. The aim of this study was to analyze the capability of dietary supplementation with either 6% olive or 6% safflower oils to regulate PGE(2), PGI(2) and NO concentrations in embryos and deciduas from control and diabetic rats during early organogenesis. Diabetes was induced by a single injection of streptozotocin (55 mg/kg) 1 week before mating. Animals were fed with the oil-supplemented diets from Days 0.5 to 10.5 of gestation. PGI(2) and PGE(2) were measured by EIA and NO through the evaluation of its stable metabolites nitrates-nitrites in 10.5 day embryos and deciduas. We found that the olive and safflower oil-supplemented treatments highly reduced resorption and malformation rates in diabetic animals, and that they were able to prevent maternal diabetes-induced alterations in embryonic and decidual PGI(2) and PGE(2) concentrations. Moreover, these dietary treatments prevented NO overproduction in embryos and deciduas from diabetic rats. These data indicate that in maternal diabetes both the embryo and the decidua benefit from the olive and safflower oil supplementation probably through mechanisms that involve the rescue of aberrant prostaglandin and NO generation and that prevent developmental damage during early organogenesis.

Distance from file tip to the major apical foramen in relation to the numeric meter reading on the display of three different electronic apex locators.

AIM: To establish and compare the relationship between the distance from the file tip to the apical foramen and the numeric meter reading on the display of three different electronic apex locators (EALs). METHODOLOGY: A total of 12 extracted intact, straight, single-rooted human teeth with complete roots were used. The actual root canal length (AL) was determined after access preparation. For the electronic measurements with each EAL, silicon stops were fixed with auto-polymerizing resin to size 15 K-files at AL and 0.5, 1, 2, 3, 4 mm short of AL. The data was analysed by two-way anova and Tukey's honestly significant difference (HSD) test for multiple comparisons amongst EALs. Additionally, one-way anova and Tukey's HSD test were carried out for multiple comparisons amongst the measurements of each EAL. RESULTS: There was a statistically significant difference amongst all EALs in indicating the position of file tips in relation to the major foramen (P < 0.05). The correlation between the meter reading and the position of the file tip from the apical foramen was statistically significant in the three EALs. There were significant differences amongst the measurements at distances from 0 to 2 mm in Justy III. In Dentaport, significant differences were found from 0 to 1 mm. However, the E-Magic Finder showed significant differences from 0 to 0.5 mm. CONCLUSIONS: Justy III was more capable of displaying the intracanal position of the file tip from the major foramen in mm whilst advancing through the root canal during electronic measurements than the Dentaport and E-Magic Finder Deluxe.