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91.
Effects of adding different concentrations of melatonin (10?7, 10?9 and 10?11 M) to maturation (Experiment 1; Control, IVM  + 10?7, IVM  + 10?9, IVM  + 10?11) and culture media (Experiment 2; Control, IVC  + 10?7, IVC  + 10?9, IVC  + 10?11) were evaluated on in vitro bovine embryonic development. The optimal concentration of melatonin (10?9 M) from Experiments 1–2 was tested in both maturation and/or culture media of Experiment 3 (Control, IVM  + 10?9, IVC  + 10?9, IVM /IVC  + 10?9). In Experiment 1, maturated oocytes from Control and IVM  + 10?9 treatments showed increased glutathione content, mitochondrial membrane potential and percentage of Grade I blastocysts (40.6% and 43%, respectively). In Experiment 2, an increase in the percentage of Grade I blastocysts was detected in IVC  + 10?7 (43.5%; 56.7%) and IVC  + 10?9 (47.4%; 57.4%). Moreover, a lower number and percentage of apoptotic cells in blastocysts were observed in the IVC  + 10?9 group compared to Control (3.8 ± 0.6; 3.6% versus 6.1 ± 0.6; 5.3%). In Experiment 3, the IVC  + 10?9 treatment increased percentage of Grade I blastocysts with a lower number of apoptotic cells compared to IVM /IVC  + 10?9 group (52.6%; 3.0 ± 0.5 versus 46.0%; 5.4 ± 1.0). The IVC  + 10?9 treatment also had a higher mRNA expression of antioxidant gene (SOD 2) compared to the Control, as well as the heat shock protein (HSPB 1) compared to the IVM  + 10?9. Reactive oxygen species production was greater in the IVM /IVC  + 10?9 treatment group. In conclusion, the 10?9 M concentration of melatonin and the in vitro production phase in which it is used directly affected embryonic development and quality.  相似文献   
92.
To assess the effect of the angiotensin‐converting enzyme (ACE) inhibition on the efficiency of the fixed‐time artificial insemination (TAI), 69 goats were divided randomly into two groups: enalapril (n = 35) and control (n = 34). In the experiment, all animals underwent the protocol of fixed‐time artificial insemination for 12 days. Enalapril group received enalapril maleate dissolved in saline (Enalapril, Lab Teuto Ltda) subcutaneously at the following doses: 0.2 mg/kg/day in D0‐D2; 0.3 mg/kg/day in D3‐D6 and 0.4 mg/kg/day in D7‐D11. The control group received the corresponding volume of 0.9% saline solution. We performed a single insemination 36 hr after sponge removal using frozen semen from two adult male goats with recognized fertility. The ultrasound pregnancy diagnosis was 30 days after the artificial insemination (AI). There was significant increase in pregnancy rates and twinning as well as a decrease in foetal loss in animals receiving enalapril (p < .01). The use of ACE inhibitors during the TAI protocol was shown to be a promising alternative to increase the efficiency of such reproductive biotechnology.  相似文献   
93.
In recent years, the interest in equine foetal gender determination (FGD) during gestation increased remarkably. Ultrasonographic FGD can be performed in two different periods during gestation. The earliest examination can take place at a gestational age of 60–70 days, whereby the genital tubercle is used to differentiate between male and female foeti. The time window of the second approach is wider (120–210 days), and there are more characteristics to take into consideration. In this article, the feasibility and accuracy of ultrasonographic FGD in mid‐ to late gestation are evaluated. One hundred twenty‐one mares from different breeds with a pregnancy stage between 120 and 270 days were examined once, using B‐scale ultrasonography (Esaote MyLab™ClassC). None of the mares were sedated nor shaved, and the procedure was completed within 15 min. Diagnosis was firstly based on the gonads. The final judgement was made based on all visible foetal reproductive organs. In three cases with a pregnancy stage beyond 257 days, FGD was not possible. All of the examined mares in which a FGD could be performed gave birth to a healthy foal. In 98% of the examinations (116/118), the diagnosis was correctly made. In both cases of misdiagnosis, only one characteristic was seen during the procedure and wrongly interpreted. Beyond 210 days of pregnancy, the extremities can preclude a good visualization of the inguinal region. In conclusion, equine FGD in mid‐ to late gestation is an accessible and accurate technique, although a good ultrasound device is a prerequisite and experience and expertise is necessary.  相似文献   
94.
Five horses with a primary surgical lesion of the small (descending) colon were diagnosed with eosinophilic colitis based on visual and histopathological examination. These were evident as visibly striking, hyperaemic, focal lesions of the small colon, with serosal petechiation, oedema and marked thickening of the intestinal wall at the site. Areas of focal necrosis were also evident. The gross appearance of the lesions were considered to be sufficiently severe in all cases to merit resection, due to concerns about intestinal necrosis and septic peritonitis. An inability to fully exteriorise the affected portion of intestine to perform a resection and anastomosis necessitated intraoperative euthanasia of one horse. A total of three horses survived to hospital discharge. Eosinophilic colitis lesions are a rare cause of severe small colon disease, but should be considered in cases with similar visual characteristics.  相似文献   
95.
Adsorbed phosphate in soils can be chemically extracted; however, this process is both time‐consuming and not cost‐effective if large numbers of samples have to be analysed. Indirect assessment of adsorbed phosphate by pedotransfer functions (PTFs) can help optimize fertilizer strategies. This study aimed to evaluate the spatial variability of adsorbed phosphate (Pads), iron oxides and magnetic susceptibility (MS) in oxisols and to calibrate PTFs to predict Pads. A total of 308 soil samples were collected from Hapludox and Eutrudox soils formed from sandstone in Brazil. The contents of clay (196–607 g/kg), iron oxides (40–165 g/kg), MS (1.2–29 × 10?6 m3/kg) and Pads (327–842 mg/kg) were in the range of typical values for these highly weathered soils. This study showed that the attributes studied were spatially dependent. Geomorphic surfaces enabled understanding of spatial variability and helped to develop a more efficient sampling scheme to calibrate PTFs. Moreover, the adsorbed phosphate in these oxisols could be predicted by a PTF using iron oxides and MS as predictors. The MS attribute enabled the most accurate prediction (concordance coefficient = 0.95, root‐mean‐square error = 46 mg/kg and relative improvement in root‐mean‐square error = ?4.12) of spatial variability through PTF compared to other predictors.  相似文献   
96.
97.
98.
The digestive process of the Pacific bluefin tuna (PBT), Thunnus orientalis, was simulated through two phases of in vitro digestion: acidic digestion with porcine pepsin, followed by alkaline digestion with pancreatic crude extract (PCE) obtained from the PBT to hydrolyze fish meal (FM) and soybean meal (SBM) as protein substrates. The crude protein from FM resulted in a lower degree of hydrolysis (73.3%) compared with SBM (79.2%). However, the resulting digested products showed that FM contained 35% more small peptides, with sizes <6.5 kDa than those from the starting material (>150 kDa). The SBM had an increase of only 1.3% in the similar peptide cut‐offs found after hydrolysis. These results suggested that FM appeared to be a better source of protein according to the amount of low‐molecular weight peptides. In addition, the proteolytic activity of PCE showed that 88.9% of its alkaline proteolytic activity corresponded to trypsin and 2.9% corresponded to chymotrypsin activity. The results shown here demonstrate that peptide sizes are important in identifying suitable protein sources for aquafeed production to reinforce the primary results obtained from the in vitro digestibility using the pH‐Stat system. These results also contribute to a better understanding of the digestibility process in aquatic organisms.  相似文献   
99.
Different stunning methods (carbon dioxide [CO2] and hypothermia) used in industrial fish processing were compared with asphyxia in air, which is used in traditional fishing, to evaluate the effects of these methods on the stress responses and the meat quality of the Amazon hybrid surubim, Pseudoplatystoma fasciatum female × Leiarius marmoratus male. After the application, blood and behavioral indicators were evaluated. Following death by gill cutting, the fish were gutted, and analyses of muscle pH, rigor mortis, the exudation of the meat, and coloration were performed. Significantly higher levels of cortisol and glucose were exhibited by the fish subjected to asphyxia than by the fish stunned by either CO2 or hypothermia. The fish subjected to asphyxia displayed decreasing muscle pH during the first 2 h after death and showed higher rates of rigor mortis after 3 h than the fish that were stunned by the other two methods. The asphyxia is a practice that exposes fish to suffering by causing an increase in stress responses, which affects meat quality. The immersion of fish in water and ice (hypothermia) for 5 min was more effective stunning method than the use of CO2, resulting in higher loss of sensibility and greater welfare.  相似文献   
100.
This study aimed to evaluate the exogenous progesterone (P4) effect on the luteal function from Day 16 to Day 21 of the oestrous cycle in inseminated goats with unknown pregnancy status. A total of 54 does passed through a short progestin-based synchronization protocol and, on Day 16 of the following oestrous cycle, 27 does received a new P4 device which was retained until Day 21. Blood samples were collected daily from all does during this period, as well as on Day 24. Pregnancy diagnoses were performed on Day 30. Serum P4 values from 26 animals (GNPSP: Group of non-pregnant does with second sponge: n = 8; GNPNSP: Group of non-pregnant does without second sponge: n = 6; GPSP: Group of pregnant does with second sponge: n = 5; GPNSP: Group of pregnant does without second sponge: n = 7) were determined by radioimmunoassay commercial kits. No P4 differences were found between groups (GNPSP: 3.1 ± 2.8; 1.7 ± 1.8; 0.4 ± 1.0; and 0.0 ± 0.0 vs. GNPNSP: 4.4 ± 1.8; 3.0 ± 2.2; 0.8 ± 0.8; and 0.0 ± 0.0 or GPSP: 4.2 ± 1.0; 3.4 ± 0.6; 3.3 ± 1.6; 3.2 ± 0.9; 3.6 ± 1.2; 3.5 ± 1.3; 2.7 ± 1.3 vs. GPNSP: 4.4 ± 1.6; 3.6 ± 1.5; 3.7 ± 1.5; 3.8 ± 1.4; 3.2 ± 1.2; 3.1 ± 1.2; 3.6 ± 1.1; D16, D17, D18, D19, D20, D21, D24, respectively) or for the interaction of group and time. In conclusion, a second progestogen device had no effect on luteolysis or early pregnancy in the following oestrous cycle.  相似文献   
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