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The objectives of the present study were to estimate the heritability for daily methane emission (CH4) and residual daily methane emission (CH4res) in Nellore cattle, as well as to perform genome-wide association studies (GWAS) to identify genomic regions and candidate genes influencing the genetic variation of CH4 and CH4res. Methane emission phenotypes of 743 Nellore animals belonging to 3 breeding programs were evaluated. CH4 was measured using the sulfur hexafluoride (SF6) tracer technique (which involves an SF6 permeation tube introduced into the rumen, and an appropriate apparatus on each animal), and CH4res was obtained as the difference between observed CH4 and CH4 adjusted for dry matter intake. A total of 6,252 genotyped individuals were used for genomic analyses. Data were analyzed with a univariate animal model by the single-step GBLUP method using the average information restricted maximum likelihood (AIREML) algorithm. The effects of single nucleotide polymorphisms (SNPs) were obtained using a single-step GWAS approach. Candidate genes were identified based on genomic windows associated with quantitative trait loci (QTLs) related to the 2 traits. Annotation of QTLs and identification of candidate genes were based on the initial and final coordinates of each genomic window considering the bovine genome ARS-UCD1.2 assembly. Heritability estimates were of moderate to high magnitude, being 0.42 ±â€…0.09 for CH4 and 0.21 ±â€…0.09 for CH4res, indicating that these traits will respond rapidly to genetic selection. GWAS revealed 11 and 15 SNPs that were significantly associated (P < 10-6) with genetic variation of CH4 and CH4res, respectively. QTLs associated with feed efficiency, residual feed intake, body weight, and height overlapped with significant markers for the traits evaluated. Ten candidate genes were present in the regions of significant SNPs; 3 were associated with CH4 and 7 with CH4res. The identified genes are related to different functions such as modulation of the rumen microbiota, fatty acid production, and lipid metabolism. CH4 and CH4res presented sufficient genetic variation and may respond rapidly to selection. Therefore, these traits can be included in animal breeding programs aimed at reducing enteric methane emissions across generations.

Genetic selection designed to reduce the amount of enteric methane emission from livestock is a mitigation strategy to ensure more sustainable production over generations since genetic gains are cumulative. Brazil is a large producer of beef, and the Nellore breed (Bos taurus indicus) plays a very important role in this production. There are a few studies evaluating genetic and genomic aspects of enteric methane emission in Nellore cattle. The objectives of the present study were to estimate the heritability of daily methane emission (CH4) and residual daily methane emission (CH4res) in Nellore cattle, as well as to identify genomic regions and candidate genes associated with genetic variation of these traits. The heritability estimates for CH4 and CH4res were of moderate to high magnitude (0.42 ±â€…0.09 and 0.21 ±â€…0.09, respectively). Genome-wide association analyses revealed new loci associated with methane emission in Nellore cattle on chromosomes 5, 11, 17, and 20, where 10 candidate genes were identified, 3 for CH4 and 7 for CH4res. The 2 traits possess sufficient genetic variability to be included as selection criteria in breeding programs.

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Evaluating traits that allow breeders to increase production efficiency in beef production systems is important. The mouth size (MS) score is a trait easily measured and implemented by breeders. Bite size is related to MS in beef cattle and is a determinant of daily feed intake of pasture-raised animals, influencing their growth. The aim of this study was to estimate genetic parameters for MS, weaning weight (WW) and postweaning weight gain (PWG) of Nelore cattle and to evaluate the influence of the interaction between MS and WW on PWG. Phenotypic records of 134,282 Nelore animals born between 1995 and 2019 were used. Variance components were estimated using multitrait animal model with the Bayesian method. The model included the contemporary group as fixed effect, age at measurement of the trait as linear covariate, and direct additive genetic and residual effects as random effects. For WW, random maternal and maternal permanent environmental effects were added to the model. A Bayesian approach was used to analyze the interaction between WW clusters and MS. The heritability estimates were 0.24, 0.15, and 0.23 for MS, WW, and PWG, respectively. The genetic correlation between variables studied ranged from 0.24 to 0.46. The results suggest that animals with a larger mouth tend to have greater PWG, demonstrating the positive influence of MS score on the postweaning performance of cattle. The direct heritability estimates confirm the possibility of selecting animals for the traits studied.

Evaluating traits that allow breeders to increase production efficiency in beef production systems is important. The mouth size (MS) score is a trait easily measured and implemented by breeders. Our results showed that MS in Nelore cattle is a heritable trait, and it is favorably associated with growth traits, indicating that animals with larger mouth are heavier at weaning and gain more weight after weaning on pasture. MS score should be further explored to evaluate its complexity and inclusion in breeding programs incorporating data collected from cattle raised under pasture conditions.

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BACKGROUND: Genotype by environment interactions (G × E) can play an important role in cattle populations and should be included in breeding programs in order to select the best animals for different environments. OBJECTIVE: The aim of this study was to investigate the G × E for milk production of Gyr cattle in Brazil and Colombia by applying a reaction norm model used genomics information, and to identify genomic regions associated with milk production in the two countries. METHODS: The Brazilian and Colombian database included 464 animals (273 cows and 33 sires from Brazil and 158 cows from Colombia) and 27,505 SNPs. A two-trait animal model was used for milk yield adjusted to 305 days in Brazil and Colombia as a function of country of origin, which included genomic information obtained with a single-step genomic reaction norm model. The GIBBS3F90 and POSTGSf90 programs were used. RESULTS: The results obtained indicate G × E based on the reranking of bulls between Brazil and Colombia, demonstrating environmental differences between the two countries. The findings highlight the importance of considering the environment when choosing breeding animals in order to ensure the adequate performance of their progeny. Within this context, the reranking of bulls and the different SNPs associated with milk production in the two countries suggest that G × E is an important effect that should be included in the genetic evaluation of Dairy Gyr cattle in Brazil and Colombia. CONCLUSION: The Gyr breeding program can be optimized by choosing a selection environment that will allow maximum genetic progress in milk production in different environments within and between countries.

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The aim of the present study was to evaluate the efficiency of selection for body growth and its association with carcass and meat quality traits in the red-winged tinamou. Two experimental groups were selected based on the selection index: selection group with a higher index (TinamouS) and commercial group with a lower index (TinamouC). Weight at 180 days and slaughter weight were significantly higher (p < 0.05) in the TinamouS group, as were hot carcass weight, skinless breast weight, wing weight, and thigh and drumstick weight. The meat quality traits or sensory attributes did not differ significantly (p > 0.05) between groups. A significant positive correlation (0.59; p < 0.05) was found between shear force and chewability and a significant negative correlation (- 0.59; p < 0.05) between aroma intensity and strange aroma. The present study suggests that the selection index promotes greater body growth and preserves meat quality and sensory traits in red-winged tinamou.

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The aim of the present study was to use different models that include body composition phenotypes for the evaluation of residual feed intake (RFI) in Nellore bulls of different ages. Phenotypic and genotypic data of bulls that had participated in feed efficiency tests of a commercial (COM) and an experimental (EXP) herd between 2007 and 2019 were used. The mean entry age in the two herds was 645 and 279 days, respectively. The phenotypes were evaluated: rib eye area (REA), backfat thickness (BFT), residual feed intake (RFIKOCH), RFI adjusted for REA (RFIREA), RFI adjusted for BFT (RFIBFT), and RFI adjusted for REA and BFT (RFIREA BFT). The (co)variance components and prediction of genomic estimated breeding values (GEBV) were obtained by REML using ssGBLUP in single and two-trait analyses. Spearman's correlations were calculated based on the GEBV for RFIKOCH. The RFI phenotypes exhibited moderate heritability estimates in both herds (0.17 ± 0.03 to 0.27 ± 0.04). The genetic correlation between phenotypes was positive and high (0.99) in the two herds, a fact that permitted the creation of a single database (SDB). The heritability estimates of the SDB were also of moderate magnitude for the different definitions of RFI (0.19 ± 0.04 to 0.21 ± 0.04). The genetic correlations were positive and high between RFI traits 0.97 ± 0.01 to 0.99 ± 0.01), and positive and low/moderate between REA and BFT (0.01 ± 0.10 to 0.31 ± 0.12). The selection of animals based on the GEBV for RFIKOCH did not alter the ranking of individuals selected for RFIREA, RFIBFT, and RFIREA BFT. The results of the present study suggest that records of Nellore bulls of different ages and with different body compositions can be combined in a SDB for RFI calculation. Therefore, young animals can be evaluated in feed efficiency tests in order to reduce costs and the generation interval and possibly to obtain a higher response to selection.

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The objective of this study was to compare the standard multi-trait model and five reduced-rank models fitted to the first principal components and genetic parameter estimates in order to determine the most appropriate method to model the covariance structure of reproductive and productive traits in Brazilian Holstein cows. Individual records of the following traits from 5217 cows were analyzed: 305-day milk yield (MY305), peak yield, milk yield per day of calving interval, days from calving to first estrus, days from calving to last service (CLS), calving interval (CI), and gestation length. Schwarz's Bayesian information criterion was used to compare the different models. The results indicated that four principal components were necessary to model the genetic (co)variance structure, reducing the number of parameters to be estimated. Analysis of genetic and phenotypic correlations showed that milk production-related traits were strongly correlated with each other (ranging from 0.74 to 0.99), while the correlation of these traits with the reproductive traits was weak (ranging from - 0.14 to 0.27). Heritability estimates for the traits ranged from 0.03 to 0.18. The reproductive traits CLS and CI and the production trait MY305 should be included as selection criteria in dairy cattle breeding programs because they are correlated with the first two principal components, retaining 91% of the genetic variability of the data.

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Multivariate procedures are used for the extraction of variables from the correlation matrix of phenotypes in order to identify those traits that explain the largest proportion of phenotypic variation and to evaluate the relationship structure between these traits. The reproductive traits (days from calving to first estrus [CFE], days from calving to last service [CLS], calving interval [CI] and gestation length [GL]) and milk production traits (milk yield at 305 days of lactation [MY305], peak yield [PY] and milk yield per day of calving interval [MYCI]) of 5,217 Holstein females (primiparous and multiparous) were measured. Principal component analysis (PCA) and factor analysis of the correlation matrix were used to estimate the correlation between traits. Analysis grouped the seven traits into three principal components and four latent factors that retained approximately 81.5% and 88.9% of the total variation of the data, respectively. The production variables exhibited positive phenotypic correlation coefficients of high magnitude (>.67). The phenotypic correlation estimates between the productive and reproductive traits were low, ranging from .13 to .22. A strong association (.99) was observed between CLS and CI. Our results indicate that multivariate analysis was effective in generating correlations between the traits studied, grouping the seven traits in a smaller number of variables that retained approximately 81% of the total variation of the data.

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PURPOSE: To analyze the prognostic role of positive cultures in patients with sepsis. METHODS: A prospective cohort study in a tertiary referral hospital in Medellín, Colombia. Adults older than 18 years of age with a bacterial infection diagnosis according to Centers for Disease Control criteria and sepsis (evidence of organ dysfunction) were included. A logistic regression model was used to determine the association between positive cultures and hospital mortality, and a Cox regression with a competing risk modeling approach was used to determine the association between positive cultures and hospital stay as well as secondary infections. RESULTS: Overall, 408 patients had positive cultures, of which 257 were blood culture, and 153 had negative cultures. Patients with positive cultures had a lower risk of mortality (odds ratio [OR], 0.43; 95% confidence interval [CI], 0.27-0.68), but this association was not maintained after adjusting for confounding factors (OR, 0.56; 95% CI, 0.31-1.01). No association was found with the hospital stay (adjusted subhazard ratio [SHR], 1.06; 95% CI, 0.83-1.35). There was no association between positive cultures and the presence of secondary infections (adjusted SHR, 0.99; 95% CI, 0.58-1.71). CONCLUSION: Positive cultures are not associated with prognosis in patients with sepsis.

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RESUMEN Objetivo: describir la experiencia de los pacientes con insulinoma, diagnosticados y tratados entre los años 2002 y 2017 en tres hospitales de la ciudad de Medellín, Colombia. Métodos: estudio descriptivo y retrospectivo de pacientes con criterios bioquímicos para hipoglucemia hiperinsulínica y confirmación histopatológica de insulinoma. Resultados: se estudiaron 19 casos, 10 eran mujeres (52,6 %), la edad media al diagnóstico fue 43 años (D.E 15,5). Hubo cuatro casos de insulinoma multifocal (21,1 %), tres asociados con NEM-1 (15,8 %) y dos malignos (10,6 %). Todos presentaron hipoglucemia en ayunas y 63,2 % posprandial. En la prueba de ayuno, el nadir de glucemia sucedió antes de 48 horas en todos los casos, en promedio 9 horas (D.E 8,0). El diagnóstico bioquímico fue realizado con hipoglucemia e insulina elevada en todos los casos, aunque el péptido C fue reportado en nueve pacientes (47,3 %) y las sulfonilureas en dos (11,1 %). La localización preoperatoria se hizo por imágenes en 12 individuos (68,5 %) y las pruebas invasivas fueron necesarias en seis (31,5 %). Las pruebas diagnósticas fueron positivas en un 83 % para resonancia, 50 % para ecografía endoscópica y prueba de estímulo intraarterial con calcio y 100 % para ecografía intraoperatoria. La cirugía se realizó en 18 casos (94,7 %). La mortalidad (15,8 %) fue derivada de complicaciones en el posoperatorio temprano; la curación se logró en todos los casos. Conclusiones: el insulinoma en nuestro medio tiene características demográficas y clínicas similares a otras series. Existen limitaciones locales para el acceso a los estudios bioquímicos y en el rendimiento diagnóstico de las pruebas de localización.

SUMMARY Objective: The objective of the study was to describe the characteristics of patients with insulinoma in three hospitals in Medellín, Colombia, between 2002 and 2017. Methods: A retrospective analysis of patients with hyperinsulinemic hypoglycemia and histologic confirmation of insulinoma was conducted. Results: A total of 19 cases were identified. Ten women (52.6 %) and 9 males (47.4 %). The mean age at diagnosis was 43 years (S.D: 15.5). Four cases had multifocal insulinoma (21.1%), 3 cases were secondary to multiple endocrine neoplasia type 1 (15.8 %), and 2 of them were malignant (10.6 %). All patients presented fasting hypo-glycemia, and 63.2% presented post-prandial hypoglycemia. Glucose nadir in the fasting test occurred in the first 48 hours in all cases, with a mean time to hypoglycemia of 9 hours (S.D 8.0). The biochemical diagnosis was done with increased insulin in the presence of hypoglycemia. C-peptide was done in 9 patients (47.3 %), and sulfonylureas in 2 cases (11.1 %). Preoperative localization was done by imaging in 12 cases (68.5 %), and invasive tests were required in 6 cases (31.5 %). Localization tests were positive as follows: magnetic resonance imaging in 83%, endoscopic ultrasound in 50%, selective intra-arterial calcium injection in 50 %, and intraoperative ultrasound in 100%. Eighteen patients (94. 7%) underwent surgery. Mortality (15.8 %) was secondary to early post-operative complications. Conclusions: The characteristics of patients with insulinoma in Medellín are similar to other series. However, there are important local limitations for proper biochemical testing and imaging localization. This is the largest study in our country.

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OBJECTIVE: To assess the true association between appropriate prescription of antibiotics and prognosis in patients with sepsis, a key issue in health care and quality improvement strategies. METHODS: Prospective cohort study in three university hospitals to determine whether the empirical prescription of antibiotics was adequate or inadequate, and to compare hospital death rates and length of stay according to different classifications of antibiotics prescription. Logistic regression models for risk estimation were fitted. RESULTS: A total of 705 patients with severe sepsis were included. No differences were found in positive-culture patients (n = 545) regarding the risk of death with insufficient spectrum antibiotics, compared to patients who received adequate spectrum antibiotics (OR = 0.90; 95% CI = 0.55-1.48). Delay in initiating antibiotics was not associated with the risk of death in patients with adequate spectrum of antibiotics, either with positive (OR = 1.04; 95% CI = 0.99-1.08) or negative cultures (OR = 0.98; 95% CI = 0.92-1.04). There were no differences in the length of hospital stay, according to the antibiotic prescription (median 11 days, IQR = 7-18 days for the whole cohort). CONCLUSIONS: No associations were found between inadequate antibiotic prescription or delay to initiate therapy and mortality or length of stay.

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Abstract Introduction: Pseudohypoparathyroidism (PHP) is a rare hereditary disease, characterized by hypocalcemia/hyperphosphatemia secondary to peripheral resistance to parathyroid hormone (PTH). PHP diagnosis is usually precluded since hypocalcemia is considered as the primary diagnosis, thus delaying further diagnostic studies and preventing an adequate management of this clinical condition. Materials and methods: Retrospective review of the databases of the Endocrinology departments of two tertiary care centers of Medellin, Colombia from January 2012 to December 2016. Patients diagnosed with PHP based on clinical presentation and confirmatory laboratory values were included. Results: Four patients met the inclusion criteria. All PHP cases were diagnosed in adulthood despite strong early clinical and laboratory evidence of the disease. Three patients were diagnosed with Fahr's syndrome and two with Albright's hereditary osteodystrophy. The mean values obtained were PTH of 376.8 pg/mL, calcium of 6.17 mg/dL and phosphorus of 6.55 mg/dL. Conclusions: PHP is a rare disorder. This paper describes four PHP cases diagnosed during adulthood. Emphasis should be placed on the judicious approach to the patient with hypocalcemia and hyperphosphatemia with increased PTH and normal renal function, since these symptoms strongly suggest a diagnosis of PHP.

Resumen Introducción. El pseudohipoparatiroidismo (PHP) es una condición rara caracterizada por hipocalcemia e hiperfosfatemia secundarias a resistencia periférica a la hormona paratiroidea (PTH). Es frecuente que la hipocalcemia sea establecida de forma equivocada como diagnóstico primario y que el diagnóstico definitivo de PHP sea tardío, difiriendo los estudios y el manejo específico que exigen estos pacientes. Materiales y métodos. Se revisaron de forma retrospectiva las bases de datos de endocrinología de dos centros terciarios de Medellín, Colombia, desde enero de 2012 a diciembre de 2016. Se incluyeron pacientes con diagnóstico de PHP por presentación clínica y valores confirmatorios de laboratorio. Resultados. Cuatro pacientes cumplieron los criterios de inclusión. Todos los casos fueron diagnosticados en la adultez a pesar de tener evidencia temprana, clínica y bioquímica de la enfermedad. Tres pacientes tenían síndrome de Fahr y dos tenían osteodistrofia hereditaria de Albright. Los valores medios registrados fueron PTH de 376.8 pg/mL, calcio de 6.17 mg/dL y fósforo de 6.55 mg/dL. Conclusiones. El PHP es un trastorno raro; se describen cuatro casos diagnosticados de forma tardía en la adultez. Se enfatiza en el enfoque juicioso del paciente con hipocalcemia, la cual, en presencia de hiperfosfatemia con PTH elevada y función renal normal, debe hacer sospechar el diagnóstico de PHP.

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El presente artículo refleja conceptos generales clínicos relacionados con una de las enfermedades de gran impacto epidemiológico a nivel nacional, que han llevado a la movilización de diferentes recursos para su control y manejo. Se presentan criterios de gran utilidad para abordar su manejo en los servicios de urgencia tomando como referencia la normatividad aprobada para su control.

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Se presentan dos casos de mujeres postmenopáusicas que consultan al servicio de urgencias presentando su primer episodio de dolor torácico desencadenado después de una situación de estrés emocional; sus EKG mostraban cambios compatibles con eventos coronarios agudos y sus niveles de Troponina T fueron francamente positivos. Al ser llevadas a coronariografía, se encontró coronarias sanas y ventriculografía con fracción de eyección disminuida. Los ecocardiogramas iniciales mostraron alteración de la contractilidad segmentaria principalmente de los segmentos apicales con confirmación de la disfunción sistólica; los de control mostraron reversión de estos hallazgos, con mejoría de la fracción de eyección; uno de los casos presentó recurrencia. El diagnóstico final de ambas pacientes fue cardiomiopatía de Tako-tsubo.

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