Hidratação enteral em equinos - solução eletrolítica associada ou não à glicose, à maltodextrina e ao sulfato de magnésio: resultados de laboratório

No presente estudo, foram avaliados os efeitos de soluções eletrolíticas administradas via sonda nasoesofágica de pequeno calibre sobre o hematócrito, o volume plasmático e as concentrações plasmáticas de proteínas totais, sódio, potássio, cloreto, magnésio total e cálcio iônico de eqüinos hígidos e desidratados experimentalmente. Foram utilizados quatro equinos adultos, mestiços, dois machos e duas fêmeas. No experimento 1 (E1Des), os animais foram desidratados experimentalmente, enquanto no 2 (E2Hig) foram utilizados equinos hígidos. Os animais foram submetidos a cada um dos seguintes tratamentos: SE - solução eletrolítica isotônica; SEGli - solução eletrolítica isotônica + glicose; SEMalt - solução eletrolítica isotônica + maltodextrina e SEMg - solução eletrolítica isotônica + sulfato de magnésio. A solução eletrolítica foi administrada na dose de 15mL kg-1 h-1, durante 12h via sonda nasoesofágica por fluxo contínuo. Os tratamentos com as soluções eletrolíticas ocasionaram expansão do volume plasmático, ocasionando a redução nos valores das proteínas plasmáticas totais e do hematócrito, enquanto os valores dos eletrólitos avaliados permaneceram na faixa de referência.In the present study, the effects of four different electrolyte solutions on the packed cell volume (PCV), plasma volume and plasma concentrations of total protein, sodium, potassium, chloride, total magnesium, and ionized calcium in healthy and experimentally dehydrated horses were evaluated. Four crossbred horses, two males and two females were used. In experiment 1 (E1Des) the animals were experimentally dehydrated, while in the second experiment (E2Hig) healthy equines were used. In both experiments the animals were subjected to the following treatments: SE - isotonic electrolyte solution; SEGlu – glucose-enriched SE; SEMalt – maltodextrine-enriched SE and SEMg - magnesium sulphate-enriched SE. The electrolyte solutions used in all treatments were administered at 15mL kg-1 h-1 during 12h through small-bore nasoesophagus tube by continuous flow. The treatments with the electrolyte solutions resulted in an increase of plasma volume and a decrease in total plasma protein, hematocrit, while the electrolytes remained within the reference values

Avaliação funcional de estruturas luteais formadas após aspiração folicular em éguas

Um grande fator limitante dos programas de transferência de embrião é o número de receptoras disponíveis durante a estação de monta. A aspiração de folículos ≥25mm promove a formação de uma estrutura lútea capaz de produzir progesterona em concentrações semelhantes ao diestro (>2ng/ml). O objetivo do presente trabalho foi avaliar a formação lútea de folículos ≥25mm aspirados, o útero e a taxa de prenhez destes animais após a inovulação. As éguas foram distribuídas aleatoriamente em três grupos: grupo controle (indução da ovulação com 2500 UI de hCG), grupo aspiração (aspiração do folículo ≥25mm) e hCG+aspiração (aplicação de 2500 UI de hCG 24h antes da aspiração de folículo ≥25mm). Cada égua foi acompanhada ultrassonograficamente para detecção da ovulação, aplicação de 7,5mg de PGF2α cinco dias após a ovulação para indução da luteólise e para determinação do momento da aspiração. O experimento foi dividido em: fase 1 – dosagens de progesterona intrafoliculares e plasmáticas e avaliação ultrassonográfica por modo B e Power Doppler das estruturas lúteas e útero; fase 2 – teste de fertilidade. As concentrações de P4 intrafoliculares foram maiores para os folículos aspirados com diâmetros maiores e a aplicação prévia do hCG aumentou estas nos folículos entre 25-29mm, bem como, a resposta ao tratamento. A aspiração folicular promoveu aumento nas concentrações de P4 plasmáticas a concentrações semelhantes ao diestro (≥2ng/mL), no entanto, as estruturas formadas a partir da aspiração apresentam luteinização mais lenta. O aumento da P4 plasmática foi capaz de promover alterações uterinas semelhantes ao diestro espontâneo e taxa de 43% de prenhez foi atingida com as éguas aspiradas. Conclui-se que a aspiração de folículos ≥25mm pode ser uma opção para...The major limiting factor of embryo transfer programs is the number of available recipient mares during the breeding season. The aspiration of follicles ≥25 mm leads to the formation of a structure capable of producing progesterone at concentrations similar to diestrus (> 2ng/ml). The present work aims to evaluate the luteal structure from ablation of follicles ≥25mm, uterine conditions and pregnancy rates after embryo transfer. Mares were randomly assigned into three groups: control group (ovulation induction with 2500 IU hCG), ablation group (follicle ≥25mm ablation) and hCG + ablation (2500 IU of hCG injection 24h before ablation of follicle ≥25mm ). Each mare was monitored by ultrasound for detection of ovulation and the determination of the time of ablation. A 7.5 mg dose of PGF2α was administered five days post ovulation to induce luteolysis. The experiment was divided into: phase 1 - intrafollicular plasma progesterone measurement and ultrasound evaluation by B-mode and power Doppler of luteal structures and uterus; phase 2 - fertility test. Concentrations of intrafollicular P4 were greater for larger follicles and hCG was efficient on increasing these levels on follicles 25-29mm, as well as increasing its response to treatment. Follicular ablation induced an increase in P4 plasma concentrations to values similar to diestrus (≥ 2ng/ml), however, the formed structures showed a delay on the luteinisation process. The increase in plasma P4 was able also to promote changes in the uterus that were similar to diestrous and these mares showed a 43% pregnancy rate. In conclusion, ablation of follicles ≥25mm can be an option for programs with limited number of recipients, however, more studies are still needed to explain ... (Complete abstract click electronic access below)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Resposta ovariana e taxa de recuperação embrionária em éguas tratadas com FSH suíno

O presente estudo tem como objetivo verificar a resposta ovulatória e recuperação embrionária em éguas após o tratamento com FSHp (Folltropin-V®) em diferentes momentos, com diferentes doses e na raça BH. O crescimento folicular foi acompanhado diariamente e os tratamentos (i.m. a cada 12h) foram mantidos até que o maior(es) folículo(s) atingiu 32mm, a indução da ovulação (2500 UI de hCG i.v.) foi realizada quando o maior(es) folículo(s) atingiu 35mm e a colheita de embriões no D8. No experimento 1, a dose de 25mg de FSHp foi testada em 28 éguas para determinação do melhor momento após aspiração folicular: 13mm (n=7, salina, controle), 13mm (n=7, FSHp-F13) e 20mm (n=7, FSHp-F20); ou em um dia determinado do ciclo: D6 (n=7, FSHp- D6). No experimento 2, a dose de 50mg de FSHp foi testada em 17 éguas quando o maior folículo atingiu 13mm (n=7, FSHp-13) e comparada ao grupo controle (n=10). No experimento 3, em 26 éguas BH inciou-se os seguintes tratamentos no D6: salina (n=7, controle), 25mg de FSHp (n=7, 25FSHp-D6), 12,5mg de EPE (n=7, EPE-D6) e 50 mg de FSHp (n=5, 50FSHp-D6). Usou-se a análise de variância de perfil, seguida do método de Tukey e para os dados de embriões/ovulação foi realizado o teste exato de Fisher (5% de significância). Os tratamentos com 25mg ou 50mg não promoveram aumento significativo no número de ovulações e de embriões recuperados, mas promoveu aumento no diâmetro máximo atingido por F3. O início do tratamento quando o maior folículo da onda induzida atingiu 20mm reduziu o tempo de tratamento. Conclui-se que os tratamentos com FSHp não promoveram resposta satisfatória e que o início do tratamento próximo ao desvio permitiu redução no tempo de tratamento.The present study aims to verify the ovulatory response and embrionary recover in mares treated at different moments with pFSH (Folltropin-V®), with different doses and in BH breeding mares. The follicular growth was daily accompanied and treatments (i.m. BID) were kept until major follicles reached 32mm, ovulation induction (2500 UI of hCH i.v.) was done when major follicles reached 35mm and embryo collection at D8. In experiment 1, 25mg of pFSH was tested in 28 mares for determination of the best moment for start of treatment after follicle ablation: 13mm (n=7, saline, control), 13mm (n=7, FSHp-F13) e 20mm (n=7, FSHp-F20); or in a previously determined cycle day: D6 (n=7, FSHp-D6). In experiment 2, 50mg of pFSH was tested in 17 mares when the largest follicle achieved 13mm (n=7, FSHp-13) and compared to a control grupo (n=10). In experiment 3, in 26 BH mares was initiated the following treatments beginning at D6: saline (n=7, control), 25mg of pFSH (n=7, 25FSHp-D6), 12,5mg of EPE (n=7, EPE-D6) e 50 mg of pFSH (n=5, 50FSHp-D6). For statistical analysis, Profile analysis followed by Tuckey method and, for embryo/ovulation, Fisher test were used (significance at 5%). Treatments with 25mg or 50mg did not promote a significative increase on ovulations and embryo recover, but increased maximum diameter of F3. The start of treatment when the largest follicle of an induced follicular wave achieved 20mm reduced time of treatment. It is concluded that pFSH treatment did not promote a satisfactory response and that beginning of treatment close to deviation allowed the reduction of treatment time.Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Uterine and luteal hemodynamic evaluation of the non pregnant mare

Background: Studies with Doppler ultrassonography started at the end of the 90s for the determination of physiological and pathological alterations in the reproductive tract of the mare. Uterine alterations caused by inflammation, response from seminal plasma infusion, hormonal variations during estrous and diestrus, pregnancy and action of various vasoactive factors influence on the vascular perfusion detected by Doppler ultrasound. The development of efficient methods for uterine quality evaluation is of big importance for field equine reproduction veterinarians, once uterine environment is responsible for pregnancy maintenance. Review: Nowadays, the most used methods of uterine evaluation are the mode B ultrassonography, cytology, culture and biopsy. Hemodynamic evaluation of the uterus can be done by spectral data collected from large vessels, as A. uterine and its ramifications, or from subjective or objective evaluations from endometrium, miometrium and mesometrium attachment, which provide data referent to local and specific alterations of the evaluated area. Alterations in uterine vascular perfusion has been detected during estrous cycle, during pregnancy and in cases of infusion of inflammatory substances. These alterations happen because of vasoactive substances that act in the uterus during these events, however, most of these vasoactive substances are probably not even known. Also, important hemodynamic alterations in old mares, as an increase in vascular resistance, have been described. This increase might result from fibrosis of the uterus and in women it is considered to be a cause of infertility. In mares, periglandular fibrosis of the endometrium is considered to be the major diagnosable cause of embryonic and fetal loss in older mares. For the CL, ovarian artery of the mare supplies the ovary as well as the oviduct and therefore can be used for evaluation of these areas. The CL evaluation can also be done by the percentage of luteum area with colored signals as an indicator of the extent of blood flow. The percentage of the CL area with colored signals is determined subjectively by images observations in real time and/or by a freezing Power Doppler cross-section image with the maximum number of color pixels taped and the total number of color pixels is assessed by a computer analysis system. Therefore, a high correlation between plasmatic progesterone and CL vascularization also allows the CL evalution by this technique. In a first report, CL circulation reached its maximum on D5, the progesterone concentration in peripheral blood increased until D7 and in a posterior report, maximum perfusion was achieved two days after the maximum progesterone concentration (D8). Blood flow reduced between D10-D14 some days before the plasma progesterone decrease and, during the luteolytic period (D15-D17), the decline in CL blood-flow area was greater than blood flow decrease. Conclusion: Doppler ultrassonography add knowledge about uterine viability and CL functionality can be easily used by veterinarians in the field. It is a noninvasive method that provides real time results. However, because of the short time studies in this area have been done, many other answers still need to be found until normal and pathological patterns will be established

Uterine vascular perfusion and spectral-doppler measurements during early gestation in mares: new concepts of evaluation

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Doppler ultrasonography principles and methods of evaluation of the reproductive tract in mares

Background: Doppler ultrasonography is a non-invasive real time pulse-wave technique recently used for the transrectal study of the reproductive system hemodynamics in large animals. This technic is based in the Doppler Effect Principle that proposes the change in frequency of a wave for an observer (red blood cells) moving relative to the source of the respective wave (ultrasonic transducer). This method had showed to be effective and useful for the evaluation of the in vivo equine reproductive tract increasing the diagnostic, monitoring, and predictive capabilities of theriogenology in mares. However, an accurate and truthful ultrasonic exam requires the previous knowledge of the Doppler ultrasonography principles. Review: In recent years, the capabilities of ultrasound flow imaging have increased enormously. The current Doppler ultrasound machines offer three methods of evaluation that may be used simultaneously (triplex mode). In B-mode ultrasound, a linear array of transducers simultaneously scans a plane through the tissue that can be viewed as a two-dimensional gray-scale image on screen. This mode is primarily used to identify anatomically a structure for its posterior evaluation using colored ultrasound modes (Color or Spectral modes). Colored ultrasound images of flow, whether Color or Spectral modes, are essentially obtained from measurements of moving red cells. In Color mode, velocity information is presented as a color coded overlay on top of a B-mode image, while Pulsed Wave Doppler provides a measure of the changing velocity throughout the cardiac cycle and the distribution of velocities in the sample volume represented by a spectral graphic. Color images conception varies according to the Doppler Frequency that is the difference between the frequency of received echoes by moving blood red cells and wave frequency transmitted by the transducer. To produce an adequate spectral graphic it is important determine the position and size of the simple gate. Furthermore, blood flow velocity measurement is influence by the intersection angle between ultrasonic pulses and the direction of moving blood-red cells (Doppler angle). Objectively colored ultrasound exam may be done on large arteries of the reproductive tract, as uterine and ovary arteries, or directly on the target tissue (follicle, for example). Mesovarium and mesometrium attachment arteries also can be used for spectral evaluation of the equine reproductive system. Subjectively analysis of the ovarian and uterine vascular perfusion must be done directly on the corpus luteum, follicular wall and uterus (endometrium and myometrium associated), respectively. Power-flow imaging has greater sensitivity to weak blood flow and independent of the Doppler angle, improving the evaluation of vessels with small diameters and slow blood flow. Conclusion: Doppler ultrasonography principles, methods of evaluation and reproductive system anatomy have been described. This knowledge is essential for the competent equipment acquisition and precise collection and analysis of colored ultrasound images. Otherwise, the reporting of inconsistent and not reproducible findings may result in the discredit of Doppler technology ahead of the scientific veterinary community

Real-time characterization of the uterine blood flow in mares before and after artificial insemination

The present experiment was divided into two studies to investigate the effect of age and endometrial degeneration on uterine blood flow of mares throughout the immediate post-breeding period. In study 1, uterine blood flow was characterized in mares (n = 7 mares/group) with minimal, moderate or severe endometrial degenerative changes (GI, GII and GIII, respectively). In study 2, the effect of age was investigated using young (≤ 6 years) and old (≥ 15 years) mares (n = 7 mares/group). Uterine vascular perfusion and mesometrial pulsatility index (PI) were evaluated every hour from H0 (moment immediately before AI) to H12. In study 1, a pronounced and transitory increase on uterine vascular perfusion was detected (P 0.05) and constant (P > 0.7) through the first 12h after AI. Results demonstrated, for the first time, the immediate changes on uterine vascular perfusion and mesometrial PI in response to semen infusion. Moreover, reduced blood flow of the uterus during the post-breeding period was strongly associated with endometrial degenerative changes in mares, regardless of age.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP