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1.
Biol Reprod ; 2024 Jun 10.
Artículo en Inglés | MEDLINE | ID: mdl-38857381

RESUMEN

Choline is a vital micronutrient that can be utilized in the formation of betaine and multiple phospholipids. In this study, we aimed to confirm, and expand on previous findings, how choline impacts embryos from the first 7 days of development to affect postnatal phenotype. Bos indicus embryos were cultured in a choline-free medium (termed vehicle) or medium supplemented with 1.8 mM choline Blastocyst-stage embryos were transferred into crossbred recipients. Once born, calves were evaluated at birth, 94 d, 178 d and at weaning (average age = 239 d). Following weaning, all calves were enrolled into a feed efficiency trial before being separated by sex, with males being slaughtered at approximately 580 d of age and females followed until their first pregnancy check. Results confirm that exposure of 1.8 mM choline chloride during the first 7 d of development alters postnatal characteristics of the resultant calves. Calves of both sexes from choline-treated embryos were consistently heavier through weaning and males had heavier testes at 3 mo of age. There were sex-dependent alterations in DNA methylation in whole blood caused by choline treatment. After weaning, feed efficiency was affected by an interaction with sex, with choline calves being more efficient for females and less efficient for males. Calves from choline-treated embryos were heavier, or tended to be heavier, than calves from vehicle embryos at all observations after weaning. Carcass weight was heavier for choline calves and the cross-sectional area of the Longissumus thoracis muscle was increased by choline. Few females became pregnant during the experiment although numerically more choline females were pregnant than vehicle females. Results confirm that exposure of the preimplantation embryo to 1.8 mM choline can alter phenotypes of the resultant calves through the first 19 months after birth.

2.
Health Promot Pract ; 24(4): 728-739, 2023 07.
Artículo en Inglés | MEDLINE | ID: mdl-35414293

RESUMEN

BACKGROUND AND PURPOSE: There is growing interest in expanding healthy eating interventions in the retail setting. The purpose of this study was to evaluate the implementation of a successful 2-for-1 price incentive for fruits and vegetables (F&V), including frozen and canned, that took place in partnership with a large chain grocery retailer in Maine. Intervention Approach. A randomized controlled trial (RCT) pilot study was conducted in 2015-2016, followed by a larger RCT in 2016-2017, to assess whether a supermarket double-dollar F&V incentive increased purchases of these items. EVALUATION METHODS: A convergent, parallel mixed-methods design was used to examine barriers and facilitators to implementing the interventions, using six implementation outcomes: acceptability, adoption, appropriateness, feasibility, implementation fidelity, and perceived cost. RESULTS: The intervention was deemed highly acceptable, appropriate, and feasible by shoppers, retailers, and researchers. The F&V discount had a high rate of initial adoption. There was a moderate degree of fidelity, which improved over time based on lessons learned from the pilot and applied to the subsequent RCT. Specific costs associated with implementation from the research perspective are reported. Implications for Practice, Policy, and Research. Partnerships between academic researchers and retailers can be an effective model for improving healthful purchases among shoppers. These findings are relevant for investigators, public health advocates, and retailers interested in implementing similar grocery retail-based interventions.


Asunto(s)
Frutas , Verduras , Humanos , Motivación , Mercadotecnía , Dieta Saludable , Comercio
3.
Biol Reprod ; 102(2): 292-305, 2020 02 14.
Artículo en Inglés | MEDLINE | ID: mdl-31616926

RESUMEN

The objective was to identify the transcriptomic profile of in vitro-derived embryos with high competence to establish and maintain gestation. Embryos produced with X-sorted sperm were cultured from day 5 to day 7 in serum-free medium containing 10 ng/ml recombinant bovine colony-stimulating factor 2 (CSF2) or vehicle. The CSF2 was administered because this molecule can increase blastocyst competence for survival after embryo transfer. Blastocysts were harvested on day 7 of culture and manually bisected. One demi-embryo from a single blastocyst was transferred into a synchronized recipient and the other half was used for RNA-seq analysis. Using P < 0.01 and a fold change >2-fold or <0.5 fold as cutoffs, there were 617 differentially expressed genes (DEG) between embryos that survived to day 30 of gestation vs those that did not, 470 DEG between embryos that survived to day 60 and those that did not, 432 DEG between embryos that maintained pregnancy from day 30 to day 60 vs those where pregnancy failed after day 30, and 635 DEG regulated by CSF2. Pathways and ontologies in which DEG were overrepresented included many related to cellular responses to stress and cell survival. It was concluded that gene expression in the blastocyst is different between embryos that are competent to establish and maintain pregnancy vs those that are not. The relationship between expression of genes related to cell stress and subsequent embryonic survival probably reflects cellular perturbations caused by embryonic development taking place in the artificial environment associated with cell culture.


Asunto(s)
Blastocisto/metabolismo , Técnicas de Cultivo de Embriones/veterinaria , Transferencia de Embrión , Desarrollo Embrionario/fisiología , Regulación del Desarrollo de la Expresión Génica , Transcriptoma , Animales , Bovinos , Supervivencia Celular/fisiología , Femenino , Embarazo , Transducción de Señal/fisiología
4.
Cell Tissue Res ; 382(3): 665-678, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32710275

RESUMEN

The objective was to characterize the transcriptome profile of in vivo-derived female embryos competent to establish and maintain gestation. Blastocysts from superovulated heifers were bisected to generate two demi-embryos. One demi-embryo was transferred into a synchronized recipient and the other part was used for RNA-seq analysis. Data on transcript abundance was analyzed for 4 demi-embryos that established and maintained pregnancy to day 60 (designated as PP) and 3 that did not result in a pregnancy at day 30 (designated as NP). Using a false discovery rate of P < 0.10 as cutoff, a total of 155 genes were differentially expressed between PP and NP embryos, of which 73 genes were upregulated and 82 genes were downregulated in the PP group. The functional cluster with the greatest enrichment score for embryos that survived, representing 28 genes (48% of the annotated genes), was related to membrane proteins, particularly those related to olfaction and neural development and function. The functional cluster with the greatest enrichment score for downregulated genes in embryos that survived included terms related to oxidative phosphorylation, mitochondrial function, and transmembrane proteins. In conclusion, competence of in vivo-derived female bovine embryos to survive after transfer is associated with increased expression of genes encoding transmembrane proteins, perhaps indicative of differentiation of the inner cell mass to epiblast, and decreased expression of genes involved in oxidative phosphorylation, perhaps indicative of reduced metabolic activity.


Asunto(s)
Blastocisto/fisiología , Desarrollo Embrionario/genética , Regulación del Desarrollo de la Expresión Génica/genética , Animales , Bovinos , Femenino , Embarazo
5.
Cell Tissue Res ; 382(3): 679, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33170338

RESUMEN

The first error is on page 5. A sentence lists two genes as SCNA1A and SCNA2A but they should be SCN1A and SCN2A.

6.
Orthopade ; 49(5): 449-459, 2020 May.
Artículo en Alemán | MEDLINE | ID: mdl-31471643

RESUMEN

BACKGROUND: Osteoarthritis is the most common joint disease worldwide and mostly affects the knee joint (gonarthrosis). In treatment algorithms, technical aids in the form of laterally wedged insoles, valgizing knee braces and ankle-foot orthoses have an importance in the treatment of medial unicompartmental knee joint disease. However, national and international guidelines differ in their recommendations. INSOLES: Taking into account a great amount of scientific work, the measurable effect of laterally wedged insoles appears to be low, so that a justifying indication only exists at low gonarthrosis levels. KNEE BRACES: Valgizing knee braces have shown stronger biomechanical and clinical effects, but with a slightly increased complication potential and low compliance. Low to medium-grade arthrosis can be treated. ANKLE-FOOT ORTHOSES: Ankle-foot arthroses have not yet been conclusively examined. Initial work indicates biomechanical and clinical efficacy. The overall effects and indications appear comparable to knee braces, probably with less complication potential.


Asunto(s)
Tirantes , Ortesis del Pié , Aparatos Ortopédicos , Osteoartritis de la Rodilla/terapia , Tobillo , Fenómenos Biomecánicos , Marcha , Humanos , Articulación de la Rodilla
7.
Orthopade ; 49(3): 238-247, 2020 Mar.
Artículo en Alemán | MEDLINE | ID: mdl-31089773

RESUMEN

Although the number of major amputations is declining throughout Germany, more than 57,000 surgical procedures for amputation still take place. As a consequence of high prosthetic care costs, these often lead to disputes before the social court in which expert medical opinions are required. With knowledge of the legal norms, the remit of the expert opinion can be fulfilled. The expert begins with evaluation of the patient's file and a search of the contested parts. The investigation includes a medical history, in addition to a physical examination, in order to be able to comment on the disputed beneficial use of the therapeutic appliance and respond to questions of proof. Questionnaires may be helpful.


Asunto(s)
Amputación Quirúrgica , Miembros Artificiales , Testimonio de Experto , Alemania , Humanos , Extremidad Inferior , Encuestas y Cuestionarios
8.
J Biol Regul Homeost Agents ; 33(6 Suppl. 1): 115-124. DENTAL SUPPLEMENT, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-31829001

RESUMEN

Innovative implant thread design enables timesaving one-stage insertion, with no need for prior osteotomy. This technique may impair bone and implant surface. The aim of this study was to investigate the strain levels produced in surrounding bone by this new treatment approach during and after implant placement and the effect of high insertion torque on the surface microstructure of the implants. Fresh bovine bone was collected and prepared to receive 2 types of drill-less self-threading dental implants differing in their thread design. Prior to implant insertion, two strain-gauges were cemented onto the bovine bone at each of the implant's neck recipient sites, one horizontally and one vertically. 5 Type 1 and 5 Type 2 implants were inserted into the bone with insertion torque of 80 Ncm. Strain was measured during implant insertion, and residual strain was recorded for 1 hour after implant placement. Implants micro-structure were analyzed by SEM. These results were compared to osteotomy and implant insertion strain data of conventional dental implants. A clear pattern of higher vertical compared to horizontal strain levels can be seen in the drill-less implants, compared to the opposite in drilling and insertion of conventional implants. Type 2 drill-less implant showed the lowest strain levels of all groups. Highest horizontal strain levels were measured for insertion of standard implants. Strain recovery was least prominent in the insertion stage of standard implants. Significant more cervical compression zones were detected in type 1 implant. However, SA and Rx. Surface roughness measurements didn't show any differences. Favorable horizontal stress distribution was noted in the 2 types of the novel drill-less implants, and comparable or lower vertical strains compared to regular protocol was also noted. Residual strain was low within all dimensions of bone. Conventional implant insertion protocol delivers strain to the frequently vulnerable bone around the implant neck. Horizontal residual strain, both in drilling and inserting conventional implants, was higher than the insertion strain of the drill-less implants. Implant surface roughness was not impaired by high insertion torque. High torque implant insertion may induce positive strain distribution within coronal part of the supporting bone. Implant surface were not impaired by high torque insertion methods.

9.
J Dairy Res ; 86(4): 432-435, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31769367

RESUMEN

Contamination of raw milk by psychrotrophs can lead to the production of heat-resistant proteases and subsequent spoilage of UHT milk. Therefore, this research communication evaluated the effect of a pre-milking teat disinfectant (active components: L-(+)-lactic acid and salicylic acid) and a liner disinfectant (active components: peracetic acid and hydrogen peroxide) on the number of mesophilic and (proteolytic) psychrotrophic bacteria prior to milking. The teat orifices of 10 cows were sampled using a swabbing procedure before and after treatment with a pre-milking teat disinfectant on six subsequent days. On the teat orifices, there was a small but statistically significant decrease in the psychrotrophic bacterial counts between pre and post dipping. No differences were observed for the mesophilic bacterial counts and proteolytic active counts. Liners were also sampled using swabs pre and post disinfection. No statistically significant decrease in the bacterial counts was observed post liner disinfection, although there was a numerical decrease. Sixty-two percent of the proteolytic psychrotrophs were pseudomonads: 16.5% of which were P. fragi, 14.3% P. lundensis, 10.0% P. fluorescens and 2.9% P. putida. Trinitrobenzenesulfonic acid (TNBS) analysis revealed a wide variety in proteolytic activity (from 0 to 55 µmol glycine/ml milk) and the presence of high producers. It can be concluded that there was only a minor effect of teat and liner disinfection on the psychrotrophic bacterial counts indicating that the measures presented did not result in a reduction of the targeted bacteria on teat orifices and liners.


Asunto(s)
Crianza de Animales Domésticos , Bacterias/efectos de los fármacos , Bovinos , Desinfectantes/farmacología , Contaminación de Equipos , Animales , Desinfección/métodos , Femenino
11.
Lupus ; 27(6): 982-990, 2018 May.
Artículo en Inglés | MEDLINE | ID: mdl-29451066

RESUMEN

BACKGROUND: The Multidimensional Health Assessment Questionnaire (MDHAQ) is a patient-reported outcome (PRO) tool that includes the Routine Assessment of Patient Index Data 3 (RAPID3), an index that can be calculated at the point of care. The objective of this study was to perform psychometric analyses of MDHAQ/RAPID3 to study its measurement properties in systemic lupus erythematosus (SLE). METHODS: The MDHAQ was completed by 161 SLE patients in routine care, along with LupusPRO (a disease-specific PRO). The SLE disease-specific activity index (SELENA-SLEDAI) and damage (SDI) were assessed. Data from 70 patients with rheumatoid arthritis who had completed MDHAQ during their routine medical care were used as controls to compare the results of Physical Function (FN) domain exploratory factor analysis. Internal consistency reliability (ICR) for FN items was calculated using Cronbach's α. Validity of MDHAQ/RAPID3 was evaluated for content validity and construct validity. Responsiveness of the RAPID3 to changes in disease activity anchors was assessed. RESULTS: The ICR of the 10 physical function items on Cronbach's α was 0.88. Exploratory factor analysis revealed cross-loadings of three FN items. RAPID3 showed a strong correlation with LupusPRO health-related quality of life score (rho -0.68 (p < 0.001)), indicating convergent validity. RAPID3 scores did not correlate with disease activity indices or SDI. After adjustment for fibromyalgia status, a weak correlation with the Physician's Global Assessment (PGA) (rho = 0.31, p = 0.008) was noted. RAPID3 could differentiate between SLE patients based on flare status. RAPID3 was not responsive to changes in PGA, SELENA-SLEDAI or SELENA-Flare Index. CONCLUSIONS: MDHAQ/RAPID3 has fair reliability and validity in SLE.

12.
Lupus ; 27(5): 728-737, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-29087259

RESUMEN

Objectives LupusPRO has shown good measurement properties as a disease-specific patient-reported outcome tool in systemic lupus erythematosus (SLE). For the purpose of clinical trials, the version 1.7 (v1.7) domain of Pain-Vitality was separated into distinct Pain, Vitality and Sleep domains in v1.8, and the psychometric properties examined. Methods A total of 131 consecutive SLE patients were self-administered surveys assessing fatigue (FACIT, SF-36), pain (Pain Inventory, SF-36), insomnia (Insomnia Severity Index), emotional health (PHQ-9, SF-36) and quality of life (SF-36, LupusPRO) at routine care visits. Internal consistency reliability (ICR) for each domain was obtained using Cronbach's alpha. The convergent construct validity of LupusPRO domains with corresponding SF-36 domains or tools were tested using Spearman correlation. Varimax rotations were conducted to assess factor structures of the LupusPRO v1.8. Results Mean (SD) age was 40.04 (14.10) years. Scores from the LupusPRO-Sleep domain strongly correlated with insomnia scores, while LupusPRO-Vitality correlated strongly with fatigue (FACIT) and SF-36 vitality. The LupusPRO-Pain domain correlated strongly with pain (SF36 Bodily-Pain, Pain Inventory) scores. Similarly, the LupusPRO domains of Physical and Emotional Health had significant correlations with corresponding SF-36 domains. The ICR for HRQoL and non-HRQoL were 0.96 and 0.81. LupusPRO (domains HRQoL and QoL) scores correlated with disease activity. Principal component analysis included seven factor loadings presenting for the HRQOL subscales (combined Sleep, Vitality, and Pain), and three factors for the NHRQoL (Combined Coping and Social Support). Conclusions LupusPRO v1.8 (including its Sleep, Vitality, and Pain domains) has acceptable reliability and validity. Use of LupusPRO as an outcome measure in clinical trials would facilitate responsiveness assessment.


Asunto(s)
Lupus Eritematoso Sistémico/diagnóstico , Medición de Resultados Informados por el Paciente , Adulto , Emociones , Femenino , Estado de Salud , Humanos , Lupus Eritematoso Sistémico/fisiopatología , Lupus Eritematoso Sistémico/psicología , Lupus Eritematoso Sistémico/terapia , Masculino , Salud Mental , Persona de Mediana Edad , Dolor/diagnóstico , Dolor/fisiopatología , Dolor/psicología , Dimensión del Dolor , Valor Predictivo de las Pruebas , Psicometría , Calidad de Vida , Reproducibilidad de los Resultados , Sueño , Trastornos del Inicio y del Mantenimiento del Sueño/diagnóstico , Trastornos del Inicio y del Mantenimiento del Sueño/fisiopatología , Trastornos del Inicio y del Mantenimiento del Sueño/psicología
13.
Biofouling ; 34(9): 1020-1031, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30612474

RESUMEN

Low intensity and very low-frequency electromagnetic fields (EMF) used for preventing scaling in water distribution systems were tested for the first time for their potential impact on drinking water biofilms. The assays were carried out in laboratory-scale flow-through reactors that mimic water distribution systems. The drinking water biofilms were not directly exposed to the core of the EMF generator and only subjected to waterborne electromagnetic waves. The density and chlorine susceptibility of nascent or mature biofilms grown under exposure to EMF were evaluated in soft and hard water. This EMF treatment was able to modify CaCO3 crystallization but it did not significantly affect biofilms. Indeed, over all the tested conditions, there was no significant change in cell number, or in the integrity of the cells (membrane, culturability), and no measurable effect of chlorine on the biofilm.


Asunto(s)
Biopelículas/crecimiento & desarrollo , Agua Potable/microbiología , Campos Electromagnéticos , Abastecimiento de Agua/normas , Biopelículas/efectos de los fármacos , Cloro/farmacología
14.
Osteoarthritis Cartilage ; 30(1): 9, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34903449
15.
Lupus ; 26(14): 1556-1561, 2017 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-28659044

RESUMEN

Background/purpose To plan a quality improvement project, we need to understand the practice patterns of physicians. We undertook an online survey of systemic lupus erythematosus (SLE) patients and physicians providing care to SLE patients to determine the patterns of medical care provided to SLE patients. Materials and methods Two self-report surveys were developed. A 12-item survey for the patients and a 13-item survey for physicians enquired about longitudinal care for SLE. Surveys were administered online to physicians providing care to SLE patients, and to patients who self-identified as having SLE, through the Lupus Society of Illinois. Patient and physician data were analyzed for physician practice patterns for SLE care, using chi square tests and t tests. A P value of 0.05 or less was considered significant on two-tailed tests. Results A total of 283 patients completed the survey. Mean (SD) age and disease duration of patients were 45.9 (13.2) and 12.7 (9.7) years. Half of the participants were being seen at 3-4-month intervals. More than 70% of patients reported being tested for antinuclear antibody (ANA), and 20-30% anti-ENA antibody and Sjögren's (SSA/SSB) antibodies, respectively, at each follow-up visit. Eighty-six rheumatologists completed the surveys. Mean (SD) age was 55 (12) years and 56% were men. More than half (54%) provided care only in a private practice setting. More than 80% of physicians reported seeing their SLE patients at 3-4-month interval. Only 2% reported performing ANA tests at each visit, while 4-5% performed anti-ENA and anti-SSA/SSB antibody tests at each visit for their SLE patients. More than 75% of physicians in private practice also ordered sedimentation rate at each visit for their SLE patients. Conclusions Unnecessary laboratory investigations may be being ordered routinely for patients at every visit. These results indicate a need for physician education on indications and utility of some of the laboratory tests such as ANA.


Asunto(s)
Lupus Eritematoso Sistémico/terapia , Pautas de la Práctica en Medicina/estadística & datos numéricos , Reumatólogos/estadística & datos numéricos , Procedimientos Innecesarios/estadística & datos numéricos , Adulto , Anciano , Anticuerpos Antinucleares/inmunología , Sedimentación Sanguínea , Femenino , Encuestas de Atención de la Salud , Humanos , Illinois , Lupus Eritematoso Sistémico/inmunología , Masculino , Persona de Mediana Edad , Encuestas y Cuestionarios , Factores de Tiempo
16.
J Biol Regul Homeost Agents ; 31(2 Suppl 1): 27-36, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28691451

RESUMEN

The present study was based on the screening of procedures and materials used by dentists in constructing complete removable dental prostheses, considering their professional background and years of experience. Questions arose regarding differences and similarities within the local dental society, of which approximately 75% were trained in Europeans countries with differences in academic background, and compared to international dentistry. A questionnaire web site was used in order to anonymously collect answers to the survey by general practicing and specialist dentists. The survey contained 28 multiple choice questions that were based on 5 parameters: years of experience, location of dental studies, specialization, location and field of specialization. One hundred one survey sheets were collected. The results show statistical significance (p less than 0.05) for the following comparisons: practicing time had an impact on practitioner-technician interaction, while the level of qualification had an effect on articulator and face-bow usage. Location of dental studies, specialization and residency had impact on final impression materials, teeth set-up as well as tooth shape and color selection. The differences found between dentists’ working techniques set the ground for future research that should focus on rating the success of the different methods towards a goal of creating recommendations for an ideal set of working techniques.


Asunto(s)
Prótesis Dental , Odontólogos , Encuestas y Cuestionarios , Odontólogos/educación , Europa (Continente) , Humanos
17.
J Biol Regul Homeost Agents ; 31(2 Suppl 1): 37-43, 2017.
Artículo en Inglés | MEDLINE | ID: mdl-28691452

RESUMEN

The final outcome of dental treatment needs to be not only clinically sufficient, but also esthetically pleasing. Bilateral symmetry in the maxillary incisor teeth is of significant importance in esthetic dentistry. In restorative dentistry, symmetry refers to the appearance of balance around the dental midline. The purpose of this study was to measure and compare the maxillary incisor teeth dimensions from both sides of the dental midline, in order to asses if this symmetry occurs naturally. From the student community population at Tel Aviv University, 66 students between the ages of 20-35 (35 males, 31 females) were enrolled and gave consent. The inclusion criteria for this study were: upper maxillary incisors that have never undergone restorative or rehabilitative treatment, and no history of orthodontic treatment. Standardized digital photographs were taken, and the length and width of the maxillary central and lateral incisors were measured and proportions were calculated. SPSS was used to compare the measured differences between teeth on the left versus right of the midline. Tooth proportions were not significantly different between the left and right sides. Asymmetry was found only between the lengths of the maxillary lateral incisors (p=0.009); the width for these teeth was symmetrical. A significant statistical difference was not found on most parameters when evaluating symmetry of the upper incisors. Therefore, when treating the esthetically important anterior of the mouth, care must be taken to ensure bilateral symmetry to mirror the natural symmetry found in most patients.


Asunto(s)
Incisivo/anatomía & histología , Maxilar/anatomía & histología , Odontometría , Adulto , Estética Dental , Femenino , Humanos , Israel , Masculino , Estudiantes , Universidades , Adulto Joven
18.
J Dairy Sci ; 100(7): 5729-5745, 2017 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-28457554

RESUMEN

The objective of this study was to implement an in vitro-produced embryo transfer (IVP-ET) system in an existing stochastic dynamic dairy simulation model with multitrait genetics to evaluate the genetic, technical, and financial performance of a dairy herd implementing an exclusive IVP-ET or artificial insemination (AI) system. In the AI system, sexed semen was used on the genetically best heifers only. In the IVP-ET system, all of the animals in the herd were impregnated with female sexed embryos created through in vitro fertilization of oocytes collected from animals of superior genetics for different traits of interest. Each donor was assumed to yield on average 4.25 transferable embryos per collection. The remaining animals in the herd were used as recipients and received either a fresh embryo or a frozen embryo when fresh embryos were not available. Selection of donors was random or based on the greatest estimated breeding value (EBV) of lifetime net merit (NM$), milk yield, or daughter pregnancy rate. For both the IVP-ET and AI systems, culling of surplus heifer calves not needed to replace culled cows was based on the lowest EBV for the same traits. A herd of 1,000 milking cows was simulated 15 yr over time after the start of the IVP-ET system. The default cost to produce and transfer 1 embryo was set at $165. Prices of fresh embryos at which an exclusive IVP-ET system financially breaks even with the comparable AI system in yr 15 and for an investment period of 15 yr were also estimated. More surplus heifer calves were sold from the IVP-ET systems than from the comparable AI systems. The surplus calves from the IVP-ET systems were also genetically superior to the surplus calves from the comparable AI systems, which might be reflected in their market value as a premium price. The most profitable scenario among the 4 IVP-ET scenarios in yr 15 was the one in which NM$ was maximized in the herd. This scenario had an additional profit of $8/cow compared with a similar AI scenario that maximized NM$, provided that surplus heifer calves could be sold at a premium price based on the superiority of the EBV of NM$. For the IVP-ET system to be at least as profitable as the comparable AI system during a 15-yr investment period, the surplus calves from the IVP-ET system needed to be sold at the premium prices. The break-even price of fresh embryos was estimated to be $84 for the exclusive IVP-ET system. This resulted in the same profit as the AI system, which maximized NM$ for a 15-yr investment period and in which heifer calves were sold at a premium price.


Asunto(s)
Transferencia de Embrión/veterinaria , Mejoramiento Genético/métodos , Animales , Cruzamiento , Bovinos , Industria Lechera , Selección de Donante , Transferencia de Embrión/economía , Transferencia de Embrión/instrumentación , Femenino , Inseminación Artificial/instrumentación , Inseminación Artificial/veterinaria , Embarazo , Índice de Embarazo
19.
J Dairy Sci ; 100(5): 3497-3512, 2017 May.
Artículo en Inglés | MEDLINE | ID: mdl-28318591

RESUMEN

The aim of this study was to develop and validate 2 protocols (for use on-farm and at a central location) for the reduction of Mycobacterium avium ssp. paratuberculosis (MAP) in colostrum while preserving beneficial immunoglobulins (IgG). The on-farm protocol was based on curdling of the colostrum, where the IgG remain in the whey and the MAP bacteria are trapped in the curd. First, the colostrum was diluted with water (2 volumes colostrum to 1 volume water) and 2% rennet was added. After incubation (1 h at 32°C), the curd was cut and incubated again, after which whey and curd were separated using a cheesecloth. The curd was removed and milk powder was added to the whey. Approximately 1 log reduction in MAP counts was achieved. A reduction in total proteins and IgG was observed due to initial dilution of the colostrum. After curd formation, more than 95% of the immunoglobulins remained in the whey fraction. The semi-industrial protocol was based on centrifugation, which causes MAP to precipitate, while the IgG remain in the supernatant. This protocol was first developed in the laboratory. The colostrum was diluted with skimmed colostrum (2 volumes colostrum to 1 volume skimmed colostrum), then skimmed and centrifuged (at 15,600 × g for 30 min at room temperature). We observed on average 1.5 log reduction in the MAP counts and a limited reduction in proteins and IgG in the supernatant. To obtain a semi-industrial protocol, dairy pilot appliances were evaluated and the following changes were applied to the protocol: after 2:1 dilution as above, the colostrum was skimmed and subsequently clarified, after which the cream was heat treated and added to the supernatant. To investigate the effect of the colostrum treatment on the nutritional value and palatability of the colostrum and the IgG transfer, an animal experiment was conducted with 24 calves. Six received the dam's colostrum, 6 were given untreated purchased colostrum (control), and 2 groups of 6 calves received colostrum treated according to both of the above-mentioned methods. No significant differences were found between the test groups and the dam's colostrum group in terms of animal health, IgG uptake in the blood serum, milk, or forage uptake. Two protocols to reduce MAP in colostrum (for use on-farm or at a central location) were developed. Both methods preserve the vital IgG.


Asunto(s)
Calostro/microbiología , Mycobacterium avium subsp. paratuberculosis , Animales , Bovinos , Enfermedades de los Bovinos/microbiología , Centrifugación , Paratuberculosis/microbiología
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