Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 12 de 12
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Animals (Basel) ; 14(3)2024 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-38338010

RESUMO

Q fever is a zoonotic disease that has been associated with reproductive problems in animals. As there is little epidemiological data regarding the distribution and risk factors of this disorder in cattle, the objective of this study was to evaluate the prevalence of Coxiella burnetii among dairy herds in the northwest of Spain, and to determine the on-farm risk factors associated with the disease and its effects on reproductive performance. Bulk tank milk (BTM) samples were collected from 262 commercial dairy herds from A Coruña, Lugo, and Pontevedra provinces. Data about location, mean age, and herd management features were obtained. A commercial indirect ELISA kit was used to determine the presence of antibodies against C. burnetii in BTM samples. The relationship between seropositivity to C. burnetii and the risk factors was checked using a Pearson's χ2 test and a classification tree analysis. In addition, a one-way ANOVA test and the Mann-Whitney U test were used to check the impact of seropositivity to C. burnetii on reproductive performance. A total of 60.1% of the farms tested positive for coxiellosis, the herd size, the external purchase of livestock, and the geographical area were identified as the main risk factors. Conception rate and first-service conception rate were significantly lower (p < 0.05) in positive farms (37.1 and 32.9%) compared to negative farms (39.8 and 36.1%). Similarly, positive farms had significant higher incidence of endometritis (13.7% vs. 11.2%, p < 0.05). Consequently, a high seropositivity and slightly negative effects of coxiellosis on reproductive performance were observed, which intensifies the need for further research, including the identification an active infection in positive herds and the characterization of the genotype.

2.
Animals (Basel) ; 13(18)2023 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-37760265

RESUMO

Proper selection of recipients determines the success of embryo transfer (ET) programs. Therefore, the objectives of this study were to assess the accuracy of rectal palpation (RP) in selecting recipients according to the size and firmness of their corpus luteum (CL) compared to ultrasonography (US) and progesterone determination (P4); to check if US or P4 provide additional information to RP with regard to selecting animals with higher odds of maintaining the pregnancy; and to verify the reliability of the presence of a cavity and the volume of the CL within the ovary (%CLOV) as predictors of the ET outcome. In Experiment 1, measurements for the largest and minor diameter (LADCL and MIDCL), CL area, and P4 at ET day were collected, as well as the RP score, in 94 heifers. In Experiment 2, measurements for the LADCL, MIDCL, CL volume, %CLOV, and presence of a cavity were collected, as well as data about the procedure and metabolic markers, in 108 heifers. No differences were found in Experiment 1, whereas in Experiment 2, just a tendency was observed for the variable of veterinarian. Consequently, these results suggest that RP and US are useful methods to select recipients with, that US and P4 do not offer additional data to use to select animals with higher odds of maintaining pregnancy, and that neither %CLOV nor cavitary CL were good indicators for pregnancy rates.

3.
Front Vet Sci ; 10: 1162589, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37215471

RESUMO

Introduction: Over the years, the most common methods for monitoring reproductive health in cattle have varied from transrectal palpation to B-mode ultrasonography. Nowadays, some portable ultrasound equipment includes the Doppler mode. Therefore, the aim of this study was to compare the accuracy of the different methods to assess corpus luteum (CL) functionality. Methods: In Experiment 1, 53 Holstein lactating cows undergoing a synchronization protocol were examined via transrectal palpation and B-mode scanning. Measurements for the largest diameter (LAD) and subjective size of CL (SCLS) were collected. Data were analyzed using correlation analysis and ROC Curves. In Experiment 2, 30 Holstein non-lactating cows with a CL were administered PGF2α and examined several times after injection, first in B-mode and then with Power Doppler. Measurements for LAD, CL area (CLA) and subjective and objective CL blood flow were collected. Blood samples were taken in both experiments to determine P4 concentration. Data were analyzed using correlation analysis and the GLM repeated measures test. Results: Results for Experiment 1 showed that LAD was more accurate than SCLS. In Experiment 2, CLA was the best measurement to assess CL function, although both subjective and objective CL blood flow offer accurate information 24 h after PGF2α administration. Discussion: Consequently, ultrasonography provides more accurate information about CL function than transrectal palpation. Although CLA seems to be an earlier indicator of luteal function than blood flow, 24 h after the onset of luteolysis, both parameters are valid.

4.
J Dairy Res ; : 1-4, 2022 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-35388777

RESUMO

The aim of this research communication was to examine and report the current situation of dairy farms in the province of Lugo (Galicia, Spain) regarding facility problems. We assessed the facilities of 168 free-stall dairy farms, housing in total 9228 Holstein cows in milk. Housing factors related to the resting area, circulation area, feeding area, ventilation area and milking area, as well as animal-handling features, were evaluated. Distance measurements were performed using a laser metre or a roll metric tape. A survey was conducted to gather information about cleaning and preventive protocols. Our results showed that most farms do not comply with the objective for cubicle measurements, width of the crossovers, type of flooring and presence of a quarantine pen, which may have a negative impact on the health and productivity of the animals. Therefore, to maximise the profits of the farm, the recommendations given in this study may be useful as a guide when building a new farm or remodelling the existing ones.

5.
Animals (Basel) ; 12(3)2022 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-35158566

RESUMO

The aim of this study was to verify the importance of postpartum serum levels of certain metabolic markers as risk factors for subclinical endometritis (SE). Ninety-four Holstein cows were included in the study, and examinations were carried out between 30-45 days postpartum. Rectal palpation, vaginoscopy, transrectal ultrasound, endometrial cytology, and blood sample collections were performed. The percentage of polymorphonuclear neutrophils (%PMN) on the endometrium was evaluated, as well as serum levels of glucose, cholesterol, triglyceride, albumin, hepatic enzymes, urea, non-esterified fatty acids (NEFA), and ß-hydroxybutyrate acid (BHBA). Samples with ≥8% PMN were classified as positive to subclinical endometritis. According to the serum levels of BHBA, cows were classified as clinical ketosis (>2.6 mmol/L), subclinical ketosis (1.2-2.6 mmol/L), and healthy (<1.2 mmol/L). Additionally, body condition score, parity, date of last labor, peripartum issues, insemination date, date of pregnancy diagnosis and milk production information were collected. Data were analyzed using a multiple regression analysis. The results showed that as serum levels of BHBA rose, also did the %PMN, so that up to 60% of cows with clinical ketosis suffered from SE. On the other hand, the %PMN fell as serum levels of urea and albumin increased. Consequently, good postpartum management practices and early detection of metabolic alterations are necessary measures to control predisposing factors and reduce the incidence of SE.

6.
Int J Hosp Manag ; 99: 103075, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36540544

RESUMO

This study aims to better understand how one particular personal capacity-psychological resilience-may help consumers adapt to the 'new normal' provoked by the COVID-19 pandemic in the hotel context, which is characterized by high uncertainty. We conducted a quantitative empirical study among consumers of hotel services, which showed that their psychological resilience has a negative effect on their perceived health risk and emotional risk. This negative effect on risk helps increase tourist intention to return to consuming hotel services despite the on-going pandemic. The findings are of value to the literature and the professional sector alike, as they demonstrate both relationships jointly for the first time. The work can help hotel firms to design more effective strategies for approaching customers in the 'new normal'.

7.
Reprod Domest Anim ; 53 Suppl 3: 14-22, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30474333

RESUMO

Studies performed on ejaculates from several species have identified discrete subpopulations of motile sperm. In dogs, motile sperm subpopulations have also been described in fresh and frozen-thawed semen. The subpopulation of the most rapid and progressively motile sperm has been suggested to be the most likely source of fertilizing spermatozoa. However, the significance of subpopulation differences among dogs and ejaculates relative to fertility is not known. The aim of this study was to investigate the relationship between the relative proportion of motile sperm subpopulations in frozen-thawed dog semen samples and their ability to bind to the zona pellucida of canine oocytes. Multiple linear regression analysis indicated that the subpopulation of the most rapid and progressively motile sperm was significantly and positively correlated with zona pellucida-binding assays (ZBA) outcomes: each 10% increase in this subpopulation was associated with an increase of 1.5 sperm bound per oocyte. Subpopulations of hyperactivated-like or locally motile sperm were negatively correlated with the ZBA results. It was concluded that subpopulation differences among frozen-thawed dog semen samples determined differences in the number of sperm bound to the ZP of canine oocytes.


Assuntos
Cães/fisiologia , Motilidade dos Espermatozoides/fisiologia , Interações Espermatozoide-Óvulo/fisiologia , Espermatozoides/fisiologia , Animais , Criopreservação/veterinária , Feminino , Fertilização in vitro/veterinária , Congelamento , Masculino , Oócitos , Espermatozoides/classificação , Zona Pelúcida/fisiologia
8.
Carbohydr Polym ; 102: 223-30, 2014 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-24507276

RESUMO

SEC measurements of the [η]-M relationship for alginate from Macrocystis pyrifera and the wormlike model can be used to characterize flexibility through two independent treatments (Bohdanecky's equations and HYDFIT program), both providing the same results. Two different assumptions concerning mass per unit of length lead to different conclusions. First: persistence length decreases with ionic strength (the intrinsic component of the persistence length is 11.3 nm and the electrostatic component is 6 nm when ionic strength is 0.01). Second: persistence length is independent of ionic strength (12 nm). Either of these options shows that the wormlike model in itself is not sufficient to explain flexibility over the whole range of chain lengths for these polyelectrolytes. A plausible explanation could be the presence of a combination of short-range and long-range screening effects of the ions of the solutions. This would also explain some data found in the literature regarding alginate flexibility.

9.
PLoS One ; 8(7): e69307, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23922699

RESUMO

The phosphotransferase system (PTS) is involved in the use of carbon sources in bacteria. Bacillus sphaericus, a bacterium with the ability to produce insecticidal proteins, is unable to use hexoses and pentoses as the sole carbon source, but it has ptsHI genes encoding the two general proteins of the PTS: enzyme I (EI) and the histidine phosphocarrier (HPr). In this work, we describe the biophysical and structural properties of HPr from B. sphaericus, HPr(bs), and its affinity towards EI of other species to find out whether there is inter-species binding. Conversely to what happens to other members of the HPr family, HPr(bs) forms several self-associated species. The conformational stability of the protein is low, and it unfolds irreversibly during heating. The protein binds to the N-terminal domain of EI from Streptomyces coelicolor, EIN(sc), with a higher affinity than that of the natural partner of EIN(sc), HPr(sc). Modelling of the complex between EIN(sc) and HPr(bs) suggests that binding occurs similarly to that observed in other HPr species. We discuss the functional implications of the oligomeric states of HPr(bs) for the glycolytic activity of B. sphaericus, as well as a strategy to inhibit binding between HPr(sc) and EIN(sc).


Assuntos
Bacillus/metabolismo , Proteínas de Bactérias/metabolismo , Sistema Fosfotransferase de Açúcar do Fosfoenolpiruvato/metabolismo , Proteínas de Bactérias/química , Calorimetria , Histidina , Temperatura Alta , Hidrodinâmica , Concentração de Íons de Hidrogênio , Modelos Moleculares , Peptídeos , Sistema Fosfotransferase de Açúcar do Fosfoenolpiruvato/química , Fosforilação , Ligação Proteica , Desnaturação Proteica , Dobramento de Proteína , Estrutura Secundária de Proteína , Espectrometria de Fluorescência , Streptomyces coelicolor/metabolismo , Termodinâmica
10.
Disabil Rehabil Assist Technol ; 6(4): 320-30, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-20969432

RESUMO

The usability concept refers to aspects related to the use of products that are closely linked to the user's degree of satisfaction. Our goal is to present a functional evaluation methodology for assessing the usability of sophisticated technical aids, such as a portable robot for helping disabled patients with severe spinal cord injuries. The specific manipulator used for this task is ASIBOT, a personal assistance robot totally developed by RoboticsLab at the University Carlos III of Madrid. Our purpose is also to improve some aspects of the manipulator according to the user's perception. For our case study, a population of six patients with spinal cord injury is considered. These patients have been suffering spinal cord injuries for a period of time longer than 1 year before the tests are carried out. The methodology followed for the information gathering is based on the Quebec User Evaluation of Satisfaction with assistive Technology (QUEST). Different daily functions, such as drinking, brushing one's teeth and washing one's face, are considered to assess the user's perception when using ASIBOT as a technical aid. The human factor in this procedure is the main base to establish the specific needs and tools to make the end product more suitable and usable.


Assuntos
Pessoas com Deficiência/reabilitação , Sistemas Homem-Máquina , Satisfação do Paciente , Robótica , Tecnologia Assistiva , Traumatismos da Medula Espinal/reabilitação , Atividades Cotidianas , Humanos , Projetos Piloto , Quebeque
11.
Reprod Nutr Dev ; 44(1): 79-88, 2004.
Artigo em Inglês | MEDLINE | ID: mdl-15189012

RESUMO

This study was aimed at determining if a GnRH analogue, buserelin, could be used for ovulation induction in rabbit does submitted to artificial insemination (AI) by intravaginal administration, by adding the hormone to the seminal dose. In a first experiment, 39 secondiparous experimental does (Hyplus strain PS19, Grimaud Frères, France, of about 30 weeks of age) were divided into 3 groups of 13 does each, which at the moment of AI received the following treatments, respectively: (1) control: an intramuscular injection of buserelin (0.8 microg/doe), (2) 8 microg/doe of buserelin added to the insemination dose, and (3) 16 microg/doe of buserelin added to the insemination dose. The experiment was done using 3 consecutive cycles at 42 day-intervals (n = 39). Four does from each of the 3 groups had blood taken at the fourth cycle for LH determination at 0, 60, 90, 120 and 150 min relative to AI. Kindling rates were 82% (28/34), 56% (29/36) and 85% (33/39), respectively for treatments 1, 2 and 3. In the does of groups 2 and 3, LH peaks were detected 60 min after AI, whereas in the does from group 1, the LH peak was detected 90 min after AI. Prolificacy was not different for the 3 treatments (average litter sizes ranged from 10.4 to 10.8). In a second experiment, 3 buserelin concentrations (8, 12 and 16 microg/doe) were used intravaginally and compared with the control treatment (0.8 microg/doe, via intramuscular). This experiment was done using 100 nulliparous rabbit does (Hyplus strain PS19, Grimaud Frères, France, of about 19 weeks of age) (4 groups of 25 does each) located on a commercial farm, to test if the previous results would be confirmed under field conditions. Kindling rates were no different (P < 0.05) for the 4 treatment groups [91.7% (22/24), 79.2% (19/24), 87.0% (20/23) and 87.5% (21/24) respectively for the control, 8, 12 and 16 microg of intravaginal buserelin], however, prolificacy was higher when using the maximal dose of intravaginal buserelin (11.7 vs. 9.4 for the control group). It was concluded that buserelin can be used for ovulation induction in rabbit does when included in the seminal dose, with similar AI results as those obtained when the hormone is administered intramuscularly.


Assuntos
Busserrelina/farmacologia , Fármacos para a Fertilidade Feminina/farmacologia , Indução da Ovulação/veterinária , Coelhos/fisiologia , Administração Intravaginal , Animais , Relação Dose-Resposta a Droga , Feminino , Injeções Intramusculares/veterinária , Inseminação Artificial/veterinária , Hormônio Luteinizante/sangue , Indução da Ovulação/métodos , Distribuição Aleatória , Fatores de Tempo
12.
Theriogenology ; 59(8): 1725-39, 2003 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-12566147

RESUMO

The aims of the present study were to compare the effects of two commercial preparations (Equex STM Paste or Equex Pasta), whose active ingredient is sodium dodecyl sulphate (SDS), added to a Tris-egg yolk-based extender, on post-thaw sperm survival and longevity, as well as on the intracellular Ca(2+) concentration of dog spermatozoa during incubation at 38 degrees C. One ejaculate was collected from each of eight dogs. Each ejaculate was centrifuged, the semen plasma discarded, and the sperm pellet rediluted with a Tris-glucose-egg yolk extender containing 3% glycerol (Ext-1) at a sperm concentration of 200 x 10(6) spermatozoa (spz)/ml. The diluted semen was divided in three aliquots of equal volume and allowed to equilibrate for 1h at 4 degrees C. After equilibration, the same volume of three different second extenders was added, respectively, to each of the three aliquots: (A) Ext-2A (same composition as Ext-1 except that it contained 7% glycerol and 1% Equex STM Paste), (B) Ext-2B (same composition as that of Ext-1 except that it contained 7% glycerol and 1% Equex Pasta), and (C) Ext-2 (CONTROL: same composition as that of Ext-1 except that it contained 7% glycerol). Semen samples were packed in 0.5 ml straws and frozen on a rack 4 cm above liquid nitrogen (LN(2)) in a styrofoam box. Thawing was at 70 degrees C for 8s. Sperm motility was evaluated after thawing and at 1 h intervals for 5h at 38 degrees C by subjective examination and by using a CASA system. Plasma membrane integrity and acrosomal status were evaluated at 1, 4 and 7h post-thaw using a triple staining procedure and flow cytometry. Intracellular Ca(2+) concentration of live spermatozoa was evaluated by flow cytometry at 1, 4 and 7h post-thaw after co-loading the sperm cells with the Ca(2+) indicators Fluo 3 AM and Fura Red AM, and with PI. Post-thaw sperm survival and longevity, as well as the quality of the sperm movement, were significantly better (P<0.005) when Ext-2A (containing Equex STM Paste) was used. There was no difference between Ext-2B (containing Equex Pasta) and Ext-2 (CONTROL). The mean intracellular Ca(2+) concentration (arbitrary units) of cryopreserved spermatozoa (range: 0.23+/-0.12 to 1.26+/-0.46) was higher than that of fresh spermatozoa (0.13+/-0.06). When using Ext-2A, the live spermatozoa frequently (P=0.012) appeared divided in two subpopulations, with high (1.26+/-0.46) and low (0.27+/-0.09) intracellular Ca(2+) content, respectively. When using Ext-2B or Ext-2, the live spermatozoa were more frequently seen in a single population with low intracellular Ca(2+) concentration (0.30+/-0.35 and 0.23+/-0.12, for Ext-2B and Ext-2, respectively).


Assuntos
Cálcio/análise , Sobrevivência Celular/efeitos dos fármacos , Criopreservação/veterinária , Cães , Temperatura Alta , Preservação do Sêmen/veterinária , Dodecilsulfato de Sódio/farmacologia , Espermatozoides/fisiologia , Animais , Masculino , Contagem de Espermatozoides , Motilidade dos Espermatozoides , Espermatozoides/química , Espermatozoides/efeitos dos fármacos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...