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1.
Reprod Domest Anim ; 57(8): 839-848, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35434829

RESUMO

Sustainability of dairy production depends largely on reproductive efficiency that is affected by heat stress due to high ambient temperature and humidity during summer. Supplementation of minerals has been proposed as a management strategy to minimize adverse impact of heat stress on fertility. The objective of this study was to determine the effects of an injectable mineral supplement (Fosfosan) containing selenium (Se), copper (Cu), potassium (K), magnesium (Mg) and phosphorus (P) on the ovarian structures, reproductive hormones and conception rate of heat-stressed Holstein cows. Sixteen cows were assigned during summer to one of two treatments, a control group (CON; n = 8) and a mineral-supplemented group (SUP; n = 8). Ambient temperature and relative humidity records were collected and processed to estimate the temperature-humidity index (THI), which confirmed a heat-stressed environment during the study (avg. THI = 79.4). Cows were subjected to a fixed-time artificial insemination (FTAI) program using the CIDR-Synch synchronization protocol. Traits indicative of ovarian activity were recorded during and after this protocol, as well as serum concentrations of reproductive hormones. Pregnancy diagnosis was made 28 and 35 d after FTAI. A completely randomized block design with repeated measures over time was performed to study ovarian functional structures and its hormonal profiles. Correlations and regressions were estimated to study relationships between ovarian structures and related hormones. Mineral supplementation did not increase follicular diameter or follicular populations (p > .05), yet tended to increase corpus luteum diameter (p < .10), and it enhanced (p < .01) oestrogen and progesterone serum concentrations and improved (p < .05) cow's conception rate. Diameter of dominant follicles and corpus luteum was correlated (p < .05) with oestrogen and progesterone levels, respectively, but only in mineral-treated cows. Two additional dairy herds were evaluated to confirm that mineral supplementation improved conception rate during the heat stress period (objective 2). Cows from dairy 1 received FTAI during winter (n = 401) and summer (n = 240), whereas cows from dairy 2 were bred after natural detected oestrus during winter (n = 558) and summer (n = 314). Conception rates were higher (p < .05) in winter than summer and they improved (p < .05) with mineral supplementation, but only in cows managed during summer. In conclusion, supplementation of minerals enhanced hormonal secretion from ovarian structures and improved conception rate in Holstein cows exposed to summer heat stress.


Assuntos
Doenças dos Bovinos , Transtornos de Estresse por Calor , Animais , Bovinos , Suplementos Nutricionais , Estrogênios/farmacologia , Sincronização do Estro , Feminino , Transtornos de Estresse por Calor/veterinária , Inseminação Artificial/veterinária , Lactação , Gravidez , Progesterona , Reprodução
2.
Trop Anim Health Prod ; 54(2): 88, 2022 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-35124730

RESUMO

The lactation curve in dairy cows is influenced by the calving season, which is highly dependent on the warm climate in semi-arid regions. Objective herein was to evaluate effects of calving season on the parameters and components of the lactation curve in Holstein cows. The study included 278,317 milk records collected from 1086 cows from the 1st to 5th calving and good body condition score. The cows were grouped according to the season in which they calved: winter-calved (CS1), summer-calved (CS2), and autumn-calved cows (CS3). Ambient temperature and humidity data were used to calculate the temperature-humidity index (THI). The NLIN procedure was used to estimate the parameters of the lactation curve that served to calculate the components. The mixed procedure was executed to analyze the fixed effect of calving season. Associations between lactation curve traits were tested using correlation and regression analyses. A univariate model was utilized to calculate heritability. Average THI values during the lactation period were 73.5, 68.5, and 69.5 units for CS1, CS2, and CS3 groups, respectively. Initial milk production and increasing rate to the maximum milk yield in CS1 and CS3 groups were higher (P < 0.05) than CS2 cows. However, persistency and total milk yield during the entire lactation period were superior (P < 0.05) for CS2 and CS3 cows compared to CS1 cows, probably due to the moderate heat stress during the lactation period in the CS1 group. In cows from CS2 and CS3 groups, total milk production at 305 days was moderately correlated with initial milk production (r = 0.47; P < 0.05), and highly correlated with milk yield at peak day (r = 0.91; P < 0.05) which resulted as reliable predictor for total milk yield during the entire lactation (R2 = 0.83). In conclusion, the THI prevailing during the different calving seasons appeared to be an important factor influencing the performance of the lactation curve.


Assuntos
Clima Desértico , Lactação , Animais , Bovinos , Feminino , Umidade , Leite , Estações do Ano
3.
Trop Anim Health Prod ; 50(8): 1913-1920, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29926362

RESUMO

Prolactin (PRL), growth hormone (GH), and insulin-like growth factor-1 (IGF-1) are in hormone-response pathways involved in energy metabolism during thermoregulation processes in cattle. Objective herein was to study the association between single nucleotide polymorphisms (SNP) within genes of the PRL and GH/IGF-1 pathways with fertility traits such as services per conception (SPC) and days open (DO) in Holstein cattle lactating under a hot-humid climate. Ambient temperature and relative humidity were used to calculate the temperature-humidity index (THI) which revealed that the cows were exposed to heat stress conditions from June to November of 2012 in southern Sonora, Mexico. Individual blood samples from all cows were collected, spotted on FTA cards, and used to genotype a 179 tag SNP panel within 44 genes from the PRL and GH/IGF-1 pathways. The associative analyses among SNP genotypes and fertility traits were performed using mixed-effect models. Allele substitution effects were calculated using a regression model that included the genotype term as covariate. Single-SNP association analyses indicated that eight SNP within the genes IGF-1, IGF-1R, IGFBP5, PAPPA1, PMCH, PRLR, SOCS5, and SSTR2 were associated with SPC (P < 0.05), whereas four SNP in the genes GHR, PAPPA2, PRLR, and SOCS4 were associated with DO (P < 0.05). In conclusion, SNP within genes of the PRL and GH/IGF-1 pathways resulted as predictors of reproductive phenotypes in heat-stressed Holstein cows, and these SNP are proposed as candidates for a marker-assisted selection program intended to improve fertility of dairy cattle raised in warm climates.


Assuntos
Bovinos/genética , Fertilidade/genética , Receptor IGF Tipo 1/genética , Receptores da Prolactina/genética , Receptores da Somatotropina/genética , Animais , Clima , Feminino , Genótipo , Hormônio do Crescimento , Transtornos de Estresse por Calor/veterinária , Resposta ao Choque Térmico , Fator de Crescimento Insulin-Like I , Lactação , México , Fenótipo , Polimorfismo de Nucleotídeo Único , Prolactina , Reprodução , Clima Tropical
4.
Genet Mol Res ; 16(1)2017 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-28340271

RESUMO

Fertility traits, such as heifer pregnancy, are economically important in cattle production systems, and are therefore, used in genetic selection programs. The aim of this study was to identify single nucleotide polymorphisms (SNPs) using RNA-sequencing (RNA-Seq) data from ovary, uterus, endometrium, pituitary gland, hypothalamus, liver, longissimus dorsi muscle, and adipose tissue in 62 candidate genes associated with heifer puberty in cattle. RNA-Seq reads were assembled to the bovine reference genome (UMD 3.1.1) and analyzed in five cattle breeds; Brangus, Brahman, Nellore, Angus, and Holstein. Two approaches used the Brangus data for SNP discovery 1) pooling all samples, and 2) within each individual sample. These approaches revealed 1157 SNPs. These were compared with those identified in the pooled samples of the other breeds. Overall, 172 SNPs within 13 genes (CPNE5, FAM19A4, FOXN4, KLF1, LOC777593, MGC157266, NEBL, NRXN3, PEPT-1, PPP3CA, SCG5, TSG101, and TSHR) were concordant in the five breeds. Using Ensembl's Variant Effector Predictor, we determined that 12% of SNPs were in exons (71% synonymous, 29% nonsynonymous), 1% were in untranslated regions (UTRs), 86% were in introns, and 1% were in intergenic regions. Since these SNPs were discovered in RNA, the variants were predicted to be within exons or UTRs. Overall, 160 novel transcripts in 42 candidate genes and five novel genes overlapping five candidate genes were observed. In conclusion, 1157 SNPs were identified in 62 candidate genes associated with puberty in Brangus cattle, of which, 172 were concordant in the five cattle breeds. Novel transcripts and genes were also identified.


Assuntos
Puberdade/genética , Animais , Sequência de Bases , Bovinos , Feminino , Fertilidade/genética , Genoma , Masculino , Polimorfismo de Nucleotídeo Único , Gravidez , RNA/genética , Seleção Genética , Análise de Sequência de RNA/métodos , Maturidade Sexual
5.
J Anim Breed Genet ; 131(3): 217-26, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24267979

RESUMO

A data set based on 50 studies including feed intake and utilization traits was used to perform a meta-analysis to obtain pooled estimates using the variance between studies of genetic parameters for average daily gain (ADG); residual feed intake (RFI); metabolic body weight (MBW); feed conversion ratio (FCR); and daily dry matter intake (DMI) in beef cattle. The total data set included 128 heritability and 122 genetic correlation estimates published in the literature from 1961 to 2012. The meta-analysis was performed using a random effects model where the restricted maximum likelihood estimator was used to evaluate variances among clusters. Also, a meta-analysis using the method of cluster analysis was used to group the heritability estimates. Two clusters were obtained for each trait by different variables. It was observed, for all traits, that the heterogeneity of variance was significant between clusters and studies for genetic correlation estimates. The pooled estimates, adding the variance between clusters, for direct heritability estimates for ADG, DMI, RFI, MBW and FCR were 0.32 ± 0.04, 0.39 ± 0.03, 0.31 ± 0.02, 0.31 ± 0.03 and 0.26 ± 0.03, respectively. Pooled genetic correlation estimates ranged from -0.15 to 0.67 among ADG, DMI, RFI, MBW and FCR. These pooled estimates of genetic parameters could be used to solve genetic prediction equations in populations where data is insufficient for variance component estimation. Cluster analysis is recommended as a statistical procedure to combine results from different studies to account for heterogeneity.


Assuntos
Bovinos/crescimento & desenvolvimento , Ingestão de Alimentos , Carne , Animais , Peso Corporal , Bovinos/genética , Bovinos/fisiologia , Análise por Conglomerados , Análise Discriminante , Feminino
6.
J Anim Breed Genet ; 131(6): 504-12, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-24834962

RESUMO

Assumptions of normality of residuals for carcass evaluation may make inferences vulnerable to the presence of outliers, but heavy-tail densities are viable alternatives to normal distributions and provide robustness against unusual or outlying observations when used to model the densities of residual effects. We compare estimates of genetic parameters by fitting multivariate Normal (MN) or heavy-tail distributions (multivariate Student's t and multivariate Slash, MSt and MS) for residuals in data of hot carcass weight (HCW), longissimus muscle area (REA) and 12th to 13th rib fat (FAT) traits in beef cattle using 2475 records from 2007 to 2008 from a large commercial operation in Nebraska. Model comparisons using deviance information criteria (DIC) favoured MSt over MS and MN models, respectively. The posterior means (and 95% posterior probability intervals, PPI) of v for the MSt and MS models were 5.89 ± 0.90 (4.35, 7.86) and 2.04 ± 0.18 (1.70, 2.41), respectively. Smaller values of posterior densities of v for MSt and MS models confirm that the assumption of normally distributed residuals is not adequate for the analysis of the data set. Posterior mean (PM) and posterior median (PD) estimates of direct genetic variances were variable with MSt having the highest mean value followed by MS and MN, respectively. Posterior inferences on genetic variance were, however, comparable among the models for FAT. Posterior inference on additive heritabilities for HCW, REA and FAT using MN, MSt and MS models indicated similar and moderate heritability comparable with the literature. Posterior means of genetic correlations for carcass traits were variable but positive except for between REA and FAT, which showed an antagonistic relationship. We have demonstrated that genetic evaluation and selection strategies will be sensitive to the assumed model for residuals.


Assuntos
Composição Corporal/genética , Bovinos/genética , Modelos Genéticos , Animais , Cadeias de Markov , Método de Monte Carlo , Análise Multivariada
7.
Animals (Basel) ; 14(2)2024 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-38254382

RESUMO

Anti-Müllerian hormone (AMH) is proposed as a biomarker for fertility in cattle, yet this associative relationship appears to be influenced by heat stress (HS). The objective was to test serum AMH and AMH-related single nucleotide polymorphisms (SNPs) as markers potentially predictive of reproductive traits in dairy cows experiencing HS. The study included 300 Holstein cows that were genotyped using BovineSNP50 (54,000 SNP). A genome-wide association study was then executed. Nine intragenic SNPs within the pathways that influence the AMH gene were found important with multiple comparisons adjustment tests (p < 1.09 × 10-6). A further validation study was performed in an independent Holstein cattle population, which was divided into moderate (MH; n = 152) and severe heat-stressed (SH; n = 128) groups and then subjected to a summer reproductive management program. Serum AMH was confirmed as a predictor of fertility measures (p < 0.05) in MH but not in the SH group. Cows were genotyped, which revealed four SNPs as predictive markers for serum AMH (p < 0.01), reproductive traits (p < 0.01), and additional physiological variables (p < 0.05). These SNPs were in the genes AMH, IGFBP1, LGR5, and TLR4. In conclusion, serum AMH concentrations and AMH polymorphisms are proposed as predictive markers that can be used in conjunction with genomic breeding value approaches to improve reproductive performance in Holstein cows exposed to summer HS conditions.

8.
J Anim Sci ; 1012023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-37698445

RESUMO

Pulmonary arterial pressure (PAP) can be used as an indicator of susceptibility to pulmonary hypertension and subsequent potential to develop right-sided heart failure (RHF). Previously reported heritability estimates of PAP have been moderate to high. Based on these estimates, selection for the indicator trait, PAP, could reduce the incidence of RHF due to hypoxia. Previous studies have also speculated that increased growth rates and body fat accumulation contribute to increased PAP and RHF. Research evaluating the genetic relationships between PAP and performance traits (e.g., yearling weight and postweaning gain) has yielded conflicting results, leading to ambiguity and uncertainty regarding the underlying genetic relationships. Additionally, no previous research has evaluated the relationship between PAP and ultrasound carcass traits. Therefore, the objective of this study was to estimate trait heritabilities and genetic correlations between PAP, post-weaning growth traits, and ultrasound carcass traits in Angus cattle, using data (n = 4,511) from the American Angus Association. We hypothesized that traits associated with increased growth and muscle would have a positive genetic (i.e., unfavorable) relationship with PAP. Estimates for heritability and genetic correlations were obtained using a multi-trait animal model. Heritability estimates for PAP (0.21 ± 0.04), post-weaning gain (PWG; 0.31 ± 0.04), and yearling weight (YWT; 0.37 ± 0.04) were within the range of estimates previously reported. Genetic correlations were weak (< 0.20) between PAP, PWG, and YWT. A low-to-moderate genetic correlation between PAP and ultrasound ribeye area (UREA) was found (0.25 ± 0.12). Genetic correlations between PAP, ultrasound back fat (UBF), ultrasound intramuscular fat (IMF), and ultrasound rump fat (RUMP) were weak (ranging in magnitude from -0.05 to 0.10) and therefore, do not provide strong support for the hypothesis of an antagonistic relationship between PAP and carcass ultrasound traits, while heritability estimates for UBF (0.43 ± 0.05), UREA (0.31 ± 0.04), IMF (0.35 ± 0.04), and RUMP (0.47 ± 0.05) were in the range of previously reported values.


Beef cattle residing >1,500 m are subject to reduced atmospheric oxygen levels when compared with beef cattle at lower elevations which may result in hypoxia-induced pulmonary hypertension and right-side heart failure. Breeders use pulmonary arterial pressures to identify animals at risk of right-side heart failure and to select breeding animals that are less susceptible to the problem. There is a concern that selection for growth and carcass characteristics may be increasing the incidence of heart failure in feedlot cattle at elevations <1,500 m. To address the concern, this study estimated the genetic correlations (i.e., relationships) between pulmonary arterial pressure, growth, and ultrasound carcass measures in Angus cattle. The study shows that the genetic relationships between pulmonary arterial pressure and these traits are minimal to non-existent with the exception of ultrasound ribeye area. Our estimate suggests a moderate, unfavorable relationship between pulmonary arterial pressure and ribeye area and that single-trait selection for increased ribeye area alone may result in increased susceptibility to right-side heart failure. However, selection for both traits simultaneously should overcome increases in susceptibility given the moderate strength of the genetic relationship.


Assuntos
Tecido Adiposo , Pressão Arterial , Bovinos/genética , Animais , Tecido Adiposo/diagnóstico por imagem , Ultrassonografia/veterinária , Fenótipo , Ureia , Composição Corporal/genética
9.
Biology (Basel) ; 12(5)2023 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-37237493

RESUMO

Dairy production in Holstein cows in a semiarid environment is challenging due to heat stress. Under such conditions, genetic selection for heat tolerance appears to be a useful strategy. The objective was to validate molecular markers associated with milk production and thermotolerance traits in Holstein cows managed in a hot and humid environment. Lactating cows (n = 300) exposed to a heat stress environment were genotyped using a medium-density array including 53,218 SNPs. A genome-wide association study (GWAS) detected six SNPs associated with total milk yield (MY305) that surpassed multiple testing (p < 1.14 × 10-6). These SNPs were further validated in 216 Holstein cows from two independent populations that were genotyped using the TaqMan bi-allelic discrimination method and qPCR. In these cows, only the SNPs rs8193046, rs43410971, and rs382039214, within the genes TLR4, GRM8, and SMAD3, respectively, were associated (p < 0.05) with MY305, rectal temperature (RT), and respiratory rate. Interestingly, these variables improved as the number of favorable genotypes of the SNPs increased from 0 to 3. In addition, a regression analysis detected RT as a significant predictor (R2 = 0.362) for MY305 in cows with >1 favorable genotype, suggesting this close relationship was influenced by genetic markers. In conclusion, SNPs in the genes TLR4, GRM8, and SMAD3 appear to be involved in the molecular mechanism that regulates milk production in cows under heat-stressed conditions. These SNPs are proposed as thermotolerance genetic markers for a selection program to improve the milk performance of lactating Holstein cows managed in a semiarid environment.

10.
Dig Dis Sci ; 57(4): 1069-71, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22147249

RESUMO

INTRODUCTION: A needle knife is often used to gain bile duct access when standard techniques have failed. If unsuccessful, the next step may involve either radiological- or endoscopic ultrasound-guided biliary access. However, repeat endoscopic retrograde cholangiopancreatography (ERCP) may be an option if the patient's clinical condition permits. AIM: To determine the success of repeat ERCP after failed use of a needle knife to gain biliary access. METHODS: Retrospective analysis of all patients who underwent initial unsuccessful biliary cannulation after use of a needle knife between 2007 and 2010. RESULTS: Seventy five patients were identified. Of these, 51 (68%) underwent repeat ERCP, and biliary cannulation was successful in 38 (75%). The median time to repeat ERCP was 7.7 days (range 1-28 days). Complications developed in two (4%) patients. These included one case each of wire-guided perforation and mild pancreatitis, both of which were resolved by conservative management. CONCLUSIONS: Repeat ERCP within a few days after failed use of a needle knife for biliary access is associated with acceptable success and acceptable incidence of complications, and therefore obviates the need for alternative approaches for biliary access for most patients.


Assuntos
Ductos Biliares/cirurgia , Cateterismo/instrumentação , Colangiopancreatografia Retrógrada Endoscópica/métodos , Neoplasias do Sistema Biliar/diagnóstico , Cateterismo/efeitos adversos , Colangiopancreatografia Retrógrada Endoscópica/instrumentação , Coledocolitíase/diagnóstico , Endossonografia , Humanos
11.
J Anim Sci ; 100(2)2022 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35015873

RESUMO

Pulmonary hypertension is a noninfectious disease of cattle at altitudes > 1524 m (5,000 ft). Mean pulmonary arterial pressures (PAP) are used as an indicator for pulmonary hypertension in cattle. High PAP cattle (≥50 mmHg) entering the feedlot at moderate elevations have lower feed efficiency as compared to low PAP cattle (< 50 mmHg). The impact of pulmonary arterial pressure on mitochondrial function, oxidative phosphorylation (OXPHOS) protein abundance, and meat color was examined using longissimus lumborum (LL) from high (98 ± 13 mmHg; n = 5) and low (41 ± 3 mmHg; n = 6) PAP fattened Angus steers (live weight of 588 ± 38 kg) during early postmortem period (2 and 48 h) and retail display (days 1 to 9), respectively. High PAP muscle had greater (P = 0.013) OXPHOS-linked respiration and proton leak-associated respiration than low PAP muscles at 2 h postmortem but rapidly declined to be similar (P = 0.145) to low PAP muscle by 48 h postmortem. OXPHOS protein expression was higher (P = 0.045) in low PAP than high PAP muscle. During retail display, redness, chroma, hue, ratio of reflectance at 630 and 580 nm, and metmyoglobin reducing activity decreased faster (P < 0.05) in high PAP steaks than low PAP. Lipid oxidation significantly increased (P < 0.05) in high PAP steaks but not (P > 0.05) in low PAP. The results indicated that high PAP caused a lower OXPHOS efficiency and greater fuel oxidation rates under conditions of low ATP demand in premortem beef LL muscle; this could explain the lower feed efficiency in high PAP feedlot cattle compared to low PAP counterparts. Mitochondrial integral function (membrane integrity or/and protein function) declined faster in high PAP than low PAP muscle at early postmortem. LL steaks from high PAP animals had lower color stability than those from the low PAP animals during simulated retail display, which could be partially attributed to the loss of muscle mitochondrial function at early postmortem by ROS damage in high PAP muscle.


The impact of pulmonary arterial pressure (PAP) on mitochondrial function, oxidative phosphorylation protein abundance, and meat color was examined using longissimus lumborum (LL) from high (98 ± 13 mmHg) and low (41 ± 3 mmHg) PAP fattened Angus steers (live weight of 588 ± 38 kg) during early postmortem period (2 and 48 h) and retail display (days 1 to 9), respectively. The results indicated that high PAP caused a lower oxidative phosphorylation efficiency and greater fuel oxidation rates under conditions of positive energy balance in beef LL muscle. This could explain the lower feed efficiency in high PAP feedlot cattle compared to low PAP counterparts. Mitochondrial integral function declined faster in high PAP than low PAP muscle at early postmortem. LL steaks from high PAP animals had lower color stability than those from the low PAP animals during simulated retail display, which could be partially attributed to the loss of muscle mitochondrial function at early postmortem in high PAP muscle.


Assuntos
Altitude , Carne Vermelha , Animais , Pressão Arterial , Bovinos , Cor , Carne/análise , Mitocôndrias , Músculo Esquelético/metabolismo , Carne Vermelha/análise
12.
Transl Anim Sci ; 5(1): txaa232, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33501417

RESUMO

The objectives were to determine if strategic supplementation of range cows in central Arizona with either two or four long acting (6 mo) trace mineral rumen boluses containing Cu, Se, and Co would: 1) decrease yearly calving interval; 2) increase cow body condition, milk production, or calf adjusted weaning weights; and 3) to see if any of the above traits varied by cow breed. There were 194 Hereford (H) and 132 Composite (CGC; 50% Red Angus, 25% Tarentaise, 25% Charolais) control cows, 173 H and 125 CGC 1X treated (2 boluses in late winter) cows, and 183 H and 117 CGC 2X treated (2 boluses in autumn and 2 in late winter) cows used over the 4-yr period. Cows were weighed and scored for body condition (1-9, 9 = fattest) in February, May, and September of each year. Milk production was determined by weigh-suckle-weigh on a subset of cows (n = 169) at an average of 50 d lactation. The outcomes were analyzed using a restricted maximum likelihood-based mixed-effects model that included the categorical, fixed effects of breed, bolus, and year with the interactions of breed × bolus, and breed × year. For adjusted weaning wt (WW), year × bolus was added. The random effect of cow was also included. Calving interval had only the breed × bolus interaction added to the main effects. Age of dam was added as a covariate to all models. Milk production used the same model as calving interval with the added covariate of postpartum interval. Cow body condition score and calf adjusted weaning weights differed by breed and treatment (P < 0.05) with WW being greater (P < 0.05) for calves from 2X cows than for control calves. Milk production differed by year (P < 0.0001) but did not differ by either breed or treatment (P > 0.05). Calving interval was 389 ± 2.7, 382 ± 3.2, and 378 ± 3.2 d for control, 1X, and 2X treatments, respectively and calving interval declined (P < 0.05) from the control to the 2X treatment group. Strategic supplementation via a long-acting trace mineral bolus was successful in decreasing calving interval and increasing calf-weaning weights from cattle grazed in an extensive rangeland environment.

13.
Genet Mol Res ; 9(1): 19-33, 2010 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-20082267

RESUMO

Currently, many different data types are collected by beef cattle breed associations for the purpose of genetic evaluation. These data points are all biological characteristics of individual animals that can be measured multiple times over an animal's lifetime. Some traits can only be measured once on an individual animal, whereas others, such as the body weight of an animal as it grows, can be measured many times. Data such as growth has been often referred to as "longitudinal" or "infinite-dimensional" since it is theoretically possible to observe the trait an infinite number of times over the life span of a given individual. Analysis of such data is not without its challenges, and as a result many different methods have been or are beginning to be implemented in the genetic analysis of beef cattle data, each an improvement over its predecessor. These methods of analysis range from the classic repeated measures to the more contemporary suite of random regressions that use covariance functions or even splines as their base function. Each of the approaches has both strengths and weaknesses in the analysis of longitudinal data. Here we summarize past and current genetic evaluation technology for analyzing this type of data and review some emerging technologies beginning to be implemented in national cattle evaluation schemes, along with their potential implications for the beef industry.


Assuntos
Bovinos/genética , Herança Multifatorial , Animais , Peso Corporal/genética , Cruzamento , Indústria Alimentícia , Variação Genética , Modelos Lineares , Estudos Longitudinais , Modelos Estatísticos
14.
Gut ; 58(7): 940-8, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19201775

RESUMO

OBJECTIVE: To evaluate the efficacy of adalimumab in the healing of draining fistulas in patients with active Crohn's disease (CD). DESIGN: A phase III, multicentre, randomised, double-blind, placebo controlled study with an open-label extension was conducted in 92 sites. PATIENTS: A subgroup of adults with moderate to severely active CD (CD activity index 220-450) for >or=4 months who had draining fistulas at baseline. INTERVENTIONS: All patients received initial open-label adalimumab induction therapy (80 mg/40 mg at weeks 0/2). At week 4, all patients were randomly assigned to receive double-blind placebo or adalimumab 40 mg every other week or weekly to week 56 (irrespective of fistula status). Patients completing week 56 of therapy were then eligible to enroll in an open-label extension. MAIN OUTCOME MEASURES: Complete fistula healing/closure (assessed at every visit) was defined as no drainage, either spontaneous or with gentle compression. RESULTS: Of 854 patients enrolled, 117 had draining fistulas at both screening and baseline (70 randomly assigned to adalimumab and 47 to placebo). The mean number of draining fistulas per day was significantly decreased in adalimumab-treated patients compared with placebo-treated patients during the double-blind treatment period. Of all patients with healed fistulas at week 56 (both adalimumab and placebo groups), 90% (28/31) maintained healing following 1 year of open-label adalimumab therapy (observed analysis). CONCLUSIONS: In patients with active CD, adalimumab therapy was more effective than placebo for inducing fistula healing. Complete fistula healing was sustained for up to 2 years by most patients in an open-label extension trial.


Assuntos
Anti-Inflamatórios/uso terapêutico , Anticorpos Monoclonais/uso terapêutico , Doença de Crohn/complicações , Fístula Intestinal/tratamento farmacológico , Adalimumab , Adulto , Anticorpos Monoclonais Humanizados , Método Duplo-Cego , Drenagem , Feminino , Humanos , Fístula Intestinal/etiologia , Masculino , Pessoa de Meia-Idade , Resultado do Tratamento , Cicatrização
15.
J Anim Sci ; 98(5)2020 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-32315038

RESUMO

Pulmonary arterial pressure (PAP) is a diagnostic measure used to determine an individual's susceptibility to developing high-altitude disease. The importance of PAP measures collected at elevations lower than the intended breeding elevation of the bulls (i.e., ≥1,520 m) is unknown. Therefore, the objective of this study was to determine the genetic relationship between PAP measures collected in a range of elevations using reaction norm models. A total of 9,177 PAP and elevation observations on purebred Angus cattle, which averaged 43.49 ± 11.32 mmHg and 1,878.6 ± 296.8 m, respectively, were used in the evaluation. The average age of the individuals in the evaluation was 434.04 ± 115.9 d. A random regression model containing the effects of sex, a linear covariate of age, a quadratic fixed covariate of elevation, and random effects consisting of a contemporary group and a linear regression of PAP on elevation was used for the evaluation of PAP. Two forms of PAP were evaluated with this model. First, to address the non-normality of the data, PAP was raised to the power of -2.6 (ptPAP) based on the results of a Box-Cox analysis. Second, raw PAP (rPAP) phenotypes were evaluated to compare the results to those obtained from the transformed data. For ptPAP, heritability ranged from 0.25 to 0.37 corresponding to elevations of 1,900 and 1,215 m, respectively. For rPAP, heritability ranged from 0.22 to 0.41 corresponding to elevations of 1,700 and 2,495 m, respectively. Generally, lower elevations corresponded to decreased heritabilities while higher elevations corresponded to increased heritability estimates. For ptPAP, genetic correlations ranged from 0.18 (elevation: 1,215 and 2,495 m) to 1.00. For rPAP, genetic correlations ranged from 0.08 (elevation: 1,215 and 2,495 m) to 1.00. In general, the closer the elevations in which PAP was measured, the greater the genetic relationship. The greater the difference in elevation between PAP measures resulted in lower genetic correlations. The rank correlation between expected progeny differences (EPD) for 1,215 and 2,495 m was 0.65 and 0.49 for the ptPAP and rPAP, respectively. These results suggested that PAP measures collected in lower elevations may be used as an indicator of high-altitude adaptability. In the estimation of EPD to rank sires for their suitability for use in high-elevation production systems, it is important to account for the relationships among varied altitudes.


Assuntos
Pressão Arterial/fisiologia , Bovinos/fisiologia , Modelos Estatísticos , Altitude , Animais , Cruzamento , Bovinos/genética , Feminino , Modelos Lineares , Masculino , Fenótipo , Artéria Pulmonar/fisiologia
16.
J Anim Sci ; 98(7)2020 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-32609315

RESUMO

Data on calving ease (CE) and birth, weaning weight (WW), and yearling weight (YW) were obtained from the American Simmental Association (ASA) and included pedigree and performance information on 11,640,735 animals. Our objective was to quantify differential response from selection for high CE vs. low birth weight (LBW) in first-calf Simmental heifers. We hypothesized that direct selection for CE should be used as the primary approach to reduce dystocia and mitigate losses in growth-related traits. WW and YW were adjusted to 205 and 365 d of age, respectively. Sire and maternal grandsire (co)variance components for CE, birth weight (BW), and 205-d weaning weight (205-d WW), and sire covariance components for 160-d postweaning gain (160-d gain) were estimated using a sire-maternal grandsire model. Direct and maternal expected progeny differences (EPD) for CE, BW, and 205-d WW and direct EPD for 160-d gain and 365-d yearling weight (365-d YW) for first-calf Simmental heifers population (465,710 animals) were estimated using a threshold-linear multivariate maternal animal model. This population was used to estimate genetic trends and as a selection pool (control) for various selection scenarios. Selection scenarios were high CE (HCE), LBW, the all-purpose selection index (API = -1.8 BW + 1.3 CE + 0.10 WW + 0.20 YW) of the ASA and its two derived subindices: (API1 = 1.3 CE + 0.20 YW) and (API2 = -1.8 BW + 0.20 YW), and lastly Dickerson's selection index (DSI = -3.2 BW + YW). Data for each selection scenario were created by selecting sires with EPD greater than or equal to the average along with the top 75% of dams. Comparison between selection scenarios involved evaluating the direct and maternal genetic trends from these scenarios. Direct heritabilities for CE, BW, 205-d WW, 160-d gain, and 365-d YW of Simmental cattle were 0.23, 0.52, 0.28, 0.21, and 0.33, respectively. The single trait, HCE, selection scenario, as opposed to LBW, increased the intercept for CE by 57.7% and the slopes (P < 0.001) for BW, 205-d WW, 160-d gain, and 365-d YW by 27.9%, 37.5%, 16%, and 28%, respectively. Comparisons of various selection scenarios revealed that the CE-based selection scenarios (HCE, API, and API1) had a greater response for CE and growth traits.


Assuntos
Peso ao Nascer/genética , Bovinos/genética , Distocia/veterinária , Seleção Genética , Animais , Peso Corporal/genética , Cruzamento , Bovinos/fisiologia , Distocia/genética , Feminino , Modelos Lineares , Masculino , Gravidez , Estados Unidos
17.
Can J Gastroenterol ; 23(7): 485-8, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19623331

RESUMO

BACKGROUND: Although most procedures in the endoscopy clinic are elective, emergency add-on cases in hospital-based endoscopy clinics are common, frequently consuming a great deal of time and resources relative to elective endoscopy procedures. OBJECTIVE: To determine which specific factors correlate with the high volume of add-on emergency cases in a tertiary care, hospital-based endoscopy unit. METHODS: A retrospective chart review of all gastrointestinal add-on, and electively booked cases of esophagastroduodenoscopy (EGD), colonoscopy(C) and flexible sigmoidoscopy(FS)procedures from September 2006 to May 2007, was conducted. The day of the week, month, type of procedure and physician were recorded. Emergency add-on procedures performed during the weekends were not assessed. These cases were then compared with elective cases during a similar time frame to determine differences in the aspects of add-on cases versus those that were elective. RESULTS: Seven hundred twenty-one add-on cases were reviewed (mean patient age 57.4 years; 46% women) and compared with 736 elective cases (mean age 56 years; 49% women; P not significant). Of the add-on cases, 377 (52%) were EGD, 216 C (30%) and 105 (15%) were FS, with 23 combined procedures (3.2%) versus 202 (27%) EGD, 442 (60%) C and 74 (10%) FS in the elective group. Add-on cases were more likely to be EGDs than elective cases (OR 2.7; 95% CI 1.8 to 4.3; P<0.0001) and less likely to be Cs (OR 0.24; 95% CI 0.15 to 0.38; P<0.0001). There were significantly more add-on cases on Mondays (OR 1.7; 95% CI 1.0 to 2.28; P>0.03). Conversely, there were significantly fewer procedures added on Fridays (OR 0.31; 95% CI 0.16 to 0.57; P=0.0001). There were statistically fewer add-on cases in September compared with the other months that were evaluated (OR 0.31; 95% CI 0.11 to 0.78; P=0.0006). CONCLUSION: With the present system of performing only emergency cases on the weekend, Monday tends to have more add-on cases. Consistent with the fact that upper gastrointestinal bleeding is the most common emergency condition, EGD is more common in add-on cases than with elective cases. Although speculative, the reasons for Friday having fewer add-on cases may be the result of a change of physician on call that day; consequently, most cases may be performed earlier in the week. For unknown reasons, fewer cases tend to be added on in September than in the other months evaluated. These data demonstrate that even in the same institution with similar patients, variability in the number of add-on cases likely is a result of many additional factors governing add-on cases, which require appropriate resource planning to ensure adequate allocation of services to ensure ideal patient care.


Assuntos
Procedimentos Cirúrgicos Eletivos/estatística & dados numéricos , Serviço Hospitalar de Emergência/estatística & dados numéricos , Endoscopia do Sistema Digestório/estatística & dados numéricos , Unidades Hospitalares/estatística & dados numéricos , Carga de Trabalho/estatística & dados numéricos , Adulto , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Estações do Ano
18.
Anim Genet ; 40(6): 986-8, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19744142

RESUMO

Two half-sib families of backcross progeny were produced by mating F(1) Line 1 Hereford (L1) x composite gene combination (CGC) bulls with L1 and CGC cows. Feed intake and periodic weights were measured for 218 backcross progeny. These progenies were genotyped using 232 microsatellite markers that spanned the 29 BTA. Progeny from L1 and CGC females was analysed separately using composite interval mapping to find quantitative trait loci (QTL) affecting daily dry matter intake (DMI), average daily gain (ADG), feed conversion (FCR) and residual feed intake (RFI). Results from both backcrosses were pooled to find additional QTL. In the backcross to L1, QTL were detected for RFI and DMI on BTA11, FCR on BTA16, and ADG on BTA9. In the backcross to CGC, QTL were detected for RFI on BTA10, FCR on BTA12 and 16 and ADG on BTA15 and 17. After pooling, QTL were detected for RFI on BTA 2, 6, 7, 10, 11, 13 and 16; for FCR on BTA 9, 12, 16, 17 and 21; for ADG on BTA 9, 14, 15, 17; and for DMI on BTA 2, 5, 6, 9, 10, 11, 20 and 23.


Assuntos
Bovinos/genética , Metabolismo Energético , Locos de Características Quantitativas , Ração Animal , Animais , Cruzamentos Genéticos , Feminino , Masculino , Repetições de Microssatélites
19.
Pulm Circ ; 9(1): 2045894018796804, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30124135

RESUMO

The obesity epidemic in developed societies has led to increased cardiovascular diseases including pulmonary hypertension associated with left heart disease (PH-LHD), the largest and fastest-growing class of PH. Similar to obese humans, PH and heart failure (HF) are increasingly recognized in North American fattened beef cattle. We hypothesized that PH and HF in fattened beef cattle are novel, phenotypically distinct manifestations of bovine PH arising from left ventricular (LV) dysfunction similar to obesity-related PH-LHD in humans. We conducted a semi-quantitative histopathological assessment of cardiopulmonary tissues obtained from fattened beef cattle suffering end-stage HF compared to asymptomatic cattle of equivalent age undergoing the same fattening regimens. In HF animals we observed significant LV fibrosis, abundant cardiac adipose depots, coronary artery injury, and pulmonary venous remodeling recapitulating human obesity-related PH-LHD. Additionally, striking muscularization, medial hypertrophy, adventitial fibrosis, and vasa vasorum hyperplasia in the pulmonary arterial circulation were associated with sequela of pathologic right ventricular (RV) remodeling suggesting combined pulmonary venous and arterial hypertension. The association between obesity, pathologic cardiopulmonary remodeling, and HF in fattened beef cattle appears to recapitulate the complex pathophysiology of obesity-associated PH-LHD in humans. This novel, naturally occurring, and large animal model may provide mechanistic and translational insights into human disease.

20.
Can J Gastroenterol ; 22(11): 937-40, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19018340

RESUMO

BACKGROUND/AIM: The use of infliximab in severe ulcerative colitis (UC) is established; however, its role in severe acute UC requires clarification. The present multicentre case series evaluated infliximab in hospitalized patients with steroid-refractory severe UC. METHODS: Patients from six hospitals were retrospectively evaluated. Data collection included demographics, duration of disease and previous treatments. The primary end point was response to in-hospital infliximab; defined as discharge without colectomy. RESULTS: Twenty-one patients (median age 26 years) were admitted between May 2006 and May 2008 with severe UC requiring intravenous steroids and given infliximab (median time to infusion eight days). Sixteen (76%) patients were discharged home without colectomy; three of these underwent colectomy at a later date. Of the remaining 13 patients (62%), all but two did not require further courses of steroids; six patients had infliximab as a bridge to azathioprine and seven patients were maintained on regular infliximab. Five patients required in-hospital colectomy after the initial infliximab. CONCLUSIONS: In this real-life experience of infliximab in patients with steroid-refractory severe UC, infliximab appears to be a viable rescue therapy. The majority of patients were discharged without surgery and 62% maintained response either as a bridge to azathioprine or maintenance infliximab.


Assuntos
Anticorpos Monoclonais/uso terapêutico , Colite Ulcerativa/tratamento farmacológico , Fármacos Gastrointestinais/uso terapêutico , Pacientes Internados , Doença Aguda , Adolescente , Adulto , Idoso , Colúmbia Britânica , Colite Ulcerativa/diagnóstico , Colonoscopia , Feminino , Seguimentos , Humanos , Infliximab , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Índice de Gravidade de Doença , Resultado do Tratamento , Fator de Necrose Tumoral alfa , Adulto Jovem
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