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61.
J.T. Paiva M.D.V. de Resende R.T. Resende H.R. de Oliveira H.T. Silva G.C. Caetano P.S. Lopes F.F. Silva 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2018,135(3):178-185
We aimed to estimate transgenerational epigenetic variance for body weight using genealogical and phenotypic information in meat quails. Animals were individually weighted from 1 week after hatching, with weight records at 7, 14, 21, 28, 35 and 42 days of age (BW7, BW14, BW21, BW28, BW35 and BW42, respectively). Single‐trait genetic analyses were performed using mixed models with random epigenetic effects. Variance components were estimated by the restricted maximum likelihood method. A grid search for values of autorecursive parameter (λ) ranging from 0 to 0.5 was used in the variance component estimation. This parameter is directly related to the reset coefficient (ν) and the epigenetic coefficient of transmissibility (1‐ν). The epigenetic effect was only significant for BW7. Direct heritability estimates for body weight ranged in magnitude (from 0.15 to 0.26), with the highest estimate for BW7. Epigenetic heritability was 0.10 for BW7, and close to zero for the other body weights. The inclusion of the epigenetic effect in the model helped to explain the residual and non‐Mendelian variability of initial body weight in meat quails. 相似文献
62.
Melatonin reduces apoptotic cells,SOD2 and HSPB1 and improves the in vitro production and quality of bovine blastocysts 下载免费PDF全文
TC Marques EC da Silva Santos TO Diesel LO Leme CF Martins MAN Dode BG Alves FPH Costa EB de Oliveira ML Gambarini 《Reproduction in domestic animals》2018,53(1):226-236
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
63.
Margot Van de Velde Kim Roels Cyrillus Ververs Ilse Gerits Jan Govaere 《Reproduction in domestic animals》2018,53(5):1027-1032
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
64.
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
65.
Pedotransfer functions to assess adsorbed phosphate using iron oxide content and magnetic susceptibility in an Oxisol 下载免费PDF全文
L. A. Camargo J. Marques Jr. G. T. Pereira L. R. F. Alleoni A. S. R. de S. Bahia D. De B. Teixeira 《Soil Use and Management》2016,32(2):172-182
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
66.
67.
Elayna Cristina da Silva Maciel Edivaldo Sampaio de Almeida Filho William Bertoloni Janessa Sampaio de Abreu 《Journal of the World Aquaculture Society》2014,45(1):35-44
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
68.
Alberto J. P. Nunes Hassan Sabry‐Neto Severino Oliveira‐Neto Lena Burri 《Journal of the World Aquaculture Society》2019,50(6):1048-1063
This study compared the feed preference and growth response of Litopenaeus vannamei to chemoattractants. A diet with 3% fishmeal was supplemented with either 3% salmon meal (POS), 3% soy protein concentrate (NEG), 3% krill meal (KRM), 3% squid meal (SQM), 3% shrimp head meal (SHM), 3% shrimp meal (SM), 3% squid liver meal (SLM), or 5% liquid sardine hydrolysate (SAH). Shrimp with a body weight (BW) of 0.99 ± 0.08 g were stocked at 100 animals/m2 in 56 tanks of 1 m3 and fed 10 times daily for 74 days. Feed preference was evaluated by feeding shrimp of 10.87 ± 1.82 g in excess twice a day for 10 days in two separate feeding trays allocated in 50 tanks of 0.5 m3. Survival reached 93.3 ± 5.80% and was unaffected by supplementation. Final BW was the highest for shrimp fed the KRM‐supplemented diet (11.97 ± 0.93 g), followed by POS (11.11 ± 0.77 g) and SQM (11.01 ± 1.17 g). Diets SHM, SM, SLM, and NEG showed a lower shrimp BW than POS, but were not statistically different among them. Shrimp fed the SAH diet achieved the lowest BW (10.06 ± 1.02 g). The highest gained yield was obtained with diets KRM and POS. No statistical difference was observed in shrimp yield among other diets. The lowest feed conversion ratio (FCR) was achieved with shrimp fed KRM (1.31 ± 0.05) when compared to diets SHM (1.47 ± 0.05), SAH (1.47 ± 0.07), and SLM (1.45 ± 0.17). Two‐by‐two comparisons indicated that shrimp preferred SHM and KRM, except when these were compared to SQM and SLM. No difference in feed preference was found between diets with SQM and SLM. SAH was the least preferred raw material in all comparisons. Results indicated that KRM acts as a powerful feeding effector and growth enhancer in fishmeal‐challenged diets for whiteleg shrimp. A dietary supplementation with 3% KRM is more effective than the same dose of any other chemoattractant evaluated. 相似文献
69.
Isabel Oliveira Cosentino Mario Felipe Alvarez Balaro Felipe Seabra Cardoso Leal Lucas de Figueiredo Cardoso Barbosa Fernanda Martins Gonçalves Gabriel Feliciano Felizardo Marina Monteiro Netto Felipe Zandonadi Brandão 《Reproduction in domestic animals》2020,55(11):1655-1659
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
70.
Quantifying the interactions of land management practices and agricultural productivity using a soil quality index 下载免费PDF全文
V. de Paul Obade 《Soil Use and Management》2017,33(4):639-652
It is desirable to develop an objective Soil Quality Index (SQI) to guide sustainable agronomic intensification, thereby promoting socio‐economic well‐being. This study pioneers the use of Ward's cluster and principal component regression methods to evaluate soil homogeneity and construct a SQI (expressed as %). Field data were acquired from five different sites within Ohio, USA, that were under no‐till (NT), conventional till (CT) management and natural vegetation (NV) land use. Soil pH, carbon/nitrogen (C/N) ratio, nitrate and soil organic carbon (SOC) concentrations were identified as primary drivers of soil quality. Based on Ward's cluster method, the soil properties of croplands were not significantly different from those under NV land use. However, SQI ranked surface soils under CT management as higher in quality than NV and NT managed soils, respectively. The coefficient of determination (R2) between SQI and corn (Zea mays L.) and soya bean [Glycine max (L.) Merr.] yields was 0.7 and 0.9, respectively, implying this SQI effectively relates soil properties, a function of anthropogenic land management practices, with crop yields. In future, time series analyses will be used to assess SQI versus crop yield dynamics, with key socio‐economic and climate variables. 相似文献