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31.
Efignia S. C. Camela Ricardo P. Nociti Victor J. C. Santos Beatrice I. Macente Maciej Murawski Wilter R. R. Vicente Pawel M. Bartlewski Maria Emilia F. Oliveira 《Reproduction in domestic animals》2019,54(2):131-137
There is a paucity of information on the relationships of testicular morphology, echotextural attributes, and blood flow dynamics with pubertal development of rams raised in a subtropical climate. Forty‐five Dorper rams (24 rams aged 8–11 months and 21 rams aged 12–24 months) were examined using a portable ultrasound scanner connected to a 7.5‐MHz transducer. Computer‐assisted analyses of testicular ultrasonograms utilized commercially available Image ProPlus® analytical software. Spectral Doppler scans of testicular arteries were performed immediately after scrotal (B‐mode) ultrasonography to determine peak systolic velocity (PSV), end‐diastolic velocity (EDV), resistive index (RI = [PSV?EDV]/PSV), and pulsatility index (PI = [SPV–EDV]/mean velocity) of the blood vessels. The length of the testes (9.7 ± 0.3 compared with 9.0 ± 0.2 cm) and scrotal circumference (33.3 ± 0.5 compared with 31.8 ± 0.4 cm) were greater (p < 0.05) but testicular depth (4.5 ± 0.1 compared with 4.9 ± 0.08 cm) was less (p < 0.05) in sexually mature compared with peripubertal rams. [Corrections added on 9 Jan 2019 after initial online publication: The testicular size values in the sentence were corrected.] There were no differences (p > 0.05) between the two age groups of Dorper rams in blood flow indices of testicular arteries. Mean numerical pixel values (100.5 ± 4.1 compared with 89.2 ± 4.8) and pixel heterogeneity (25.6 ± 0.6 compared with 23.6 ± 0.5) of testicular parenchyma were greater (p < 0.05) in peripubertal than in postpubertal rams. Semen volume was negatively correlated with PI of testicular arteries (r = ?0.57, p = 0.04). In summary, the attainment of sexual maturity in the rams of the present study was associated with significant changes in testicular length and depth, scrotal circumference, and parenchymal echogenicity/hetrogeneity but not in testicular volume and blood perfusion rates. Testicular artery PI can be used to predict the volume of ejaculate in rams. 相似文献
32.
Bianca Lourdes FREHNER Iris Margaret REICHLER Mariusz Pawel KOWALEWSKI Aykut GRAM Stefanie KELLER Sandra GOERICKE-PESCH Orsolya BALOGH 《The Journal of reproduction and development》2021,67(3):207
The underlying functional and molecular changes in canine primary uterine inertia (PUI) are still not clarified. Leptin (Lep) and obesity negatively affect uterine contractility in women, partly mediated by the RhoA/Rho associated kinase pathway, affecting myometrial calcium sensitization. We hypothesized that increased uterine Lep/Lep receptor (LepR) or decreased RhoA/Rho associated kinase expression contributes to PUI in dogs, independent of obesity. Dogs presented for dystocia were grouped into PUI (n = 11) or obstructive dystocia (OD, still showing strong labor contractions; n = 7). Interplacental full-thickness uterine biopsies were collected during Cesarean section for relative gene expression (RGE) of RhoA, its effector kinases (ROCK1, ROCK2), Lep and LepR by qPCR. Protein and/or mRNA expression and localization was evaluated by immunohistochemistry and in situ hybridization. RGE was compared between groups by one-way ANOVA using body weight as covariate with statistical significance at P < 0.05. Uterine ROCK1 and ROCK2 gene expression was significantly higher in PUI than OD, while RhoA and Lep did not differ. LepR RGE was below the detection limit in five PUI and all OD dogs. Litter size had no influence. Lep, LepR, RhoA, ROCK1, ROCK2 protein and/or mRNA were localized in the myometrium and endometrium. Uterine protein expression appeared similar between groups. LepR mRNA signals appeared stronger in PUI than OD. In conclusion, lasting, strong labor contractions in OD likely resulted in downregulation of uterine ROCK1 and ROCK2, contrasting the higher expression in PUI dogs with insufficient contractions. The Lep-LepR system may affect uterine contractility in non-obese PUI dogs in a paracrine-autocrine manner. 相似文献
33.
Joel S Caton Matthew S Crouse Kyle J McLean Carl R Dahlen Alison K Ward Robert A Cushman Anna T Grazul-Bilska Bryan W Neville Pawel P Borowicz Lawrence P Reynolds 《Journal of animal science》2020,98(12)
The focus of this review is maternal nutrition during the periconceptual period and offspring developmental outcomes in beef cattle, with an emphasis on the first 50 d of gestation, which represents the embryonic period. Animal agriculture in general, and specifically the beef cattle industry, currently faces immense challenges. The world needs to significantly increase its output of animal food products by 2050 and beyond to meet the food security and agricultural sustainability needs of the rapidly growing human population. Consequently, efficient and sustainable approaches to livestock production are essential. Maternal nutritional status is a major factor that leads to developmental programming of offspring outcomes. Developmental programming refers to the influence of pre-and postnatal factors, such as inappropriate maternal nutrition, that affect growth and development and result in long-term consequences for health and productivity of the offspring. In this review, we discuss recent studies in which we and others have addressed the questions, “Is development programmed periconceptually?” and, if so, “Does it matter practically to the offspring in production settings?” The reviewed studies have demonstrated that the periconceptual period is important not only for pregnancy establishment but also may be a critical period during which fetal, placental, and potentially postnatal development and function are programmed. The evidence for fetal and placental programming during the periconceptual period is strong and implies that research efforts to mitigate the negative and foster the positive benefits of developmental programming need to include robust investigative efforts during the periconceptual period to better understand the implications for life-long health and productivity. 相似文献
34.
Pawel Wojcik 《Journal of plant nutrition》2013,36(11):1897-1906
The objective of this experiment was to examine the vegetative and generative responses of highbush blueberry to boron fertilization. The study was carried out in 2002–2003 in Central Poland on mature ‘Bluecrop’ blueberries (Vaccinium corymbosum L.) planted at a spacing of 3 × 1 m on a sandy loam soil with pH value of 3.9 and low hot water soluble boron status. Blueberries were soil- or foliar-supplied with boron. Foliar boron sprays were done four times per season: at the beginning of blooming, at petal fall, and three and six weeks after the ending of flowering. In each spray treatment, boron was applied at a rate of 0.2 kg ha?1. Soil boron was applied at the stage of bud break at a rate of 2 kg ha?1. Plants untreated with boron served as control. The results showed that boron fertilization increased boron levels in flower and leaf tissues. This treatment, regardless of boron application mode, did not affect plant vigor, the number of flowers per cane, fruit set, nor yield. Also mean fruit weight and berry firmness were not influenced by boron fertilization. Fruit of boron-supplied blueberries had higher soluble solids concentrations than those of the control plants. It is concluded that boron requirements of highbush blueberry are relatively low compared to most fruit crops and that critical leaf boron concentrations of ‘Bluecrop’ blueberry are below 15 mg kg?1 DW. 相似文献
35.
Pawel Wojcik 《Journal of plant nutrition》2013,36(10):1821-1832
The objective of this study was to examine the response of red raspberry to boron (B) fertilization. The experiment was carried out during 2002–2003 in a commercial plantation in central Poland on primocane-fruiting ‘Polana’ raspberries planted on a sandy loam soil with low status of organic matter and hot water-extractable B. Raspberries were fertilized with B via foliar or soil application. Foliar B sprays were made four times per season: two weeks before flowering, at the beginning of blooming, and three and six weeks later. In each spray treatment, B was used at a rate of 0.1 kg ha?1. Soil B was applied at the stage of bud break at a rate of 1 kg ha?1. Plants untreated with B served as a control. The results showed that B fertilization, regardless of application mode, increased flower and leaf B concentrations, fruit set, and berry yield. Fruit of B-fertilized plants were firmer, and had higher soluble solids concentrations and numbers of drupelets than those of the control plants. Boron fertilization had no effect on plant vigor, mean berry weight, and titratable acidity of fruit. The obtained results indicated that on coarse-textured soils with low B status, soil or foliar B application should be recommended in red raspberry cultivation to increase yield and improve berry quality. 相似文献
36.
Dorota Fopp-Bayat Malgorzata Jankun Pawel Woznicki & Ryszard Kolman 《Aquaculture Research》2007,38(12):1301-1304
The aim of the present study was to produce Acipenser baeri× (Huso huso×Acipenser ruthenus) hybrids in a diploid and triploid state and to study their viability in comparison with the A. baeri from the fish farm stock. A heat shock (37°C) in the 18th minute after fertilization was applied to induce triploidy. The survival rate and the ploidy level of the hybrids obtained were studied. The mortality of triploid hybrids was approximately twice as high as the mortality of diploid hybrids. No significant difference in the survival rate between Siberian sturgeon and their diploid hybrid with bester was noted. Cytogenetic analysis was performed by preparing chromosomes from the gill epithelium. The results showed that all studied fish from the heat‐shocked group were triploid. 相似文献
37.
Tammi L Neville Allison M Meyer Arshi Reyaz Pawel B Borowicz Dale A Redmer Lawrence P Reynolds Joel S Caton Kimberly A Vonnahme 《畜牧与生物技术杂志(英文版)》2013,4(1):6
Background
Objectives were to examine the effects of selenium (Se) supply and maternal nutritional plane during gestation on mammary gland growth, cellular proliferation, and vascularity at parturition and d 20 of lactation. Rambouillet primiparous ewes (n = 84) were allocated to treatments in a 2 x 3 factorial. Factors were dietary Se (adequate Se [ASe, 11.5 μg/kg BW] or high Se [HSe, 77.0 μg/kg BW]) and nutritional plane (60% [RES], 100% [CON], or 140% [EXC]). At parturition, lambs were removed and 42 ewes (7/treatment) were necropsied. Remaining ewes were fed a common diet meeting requirements for lactation and mechanically milked twice daily until necropsy on d 20. At both necropsy periods, mammary glands were dissected and tissues harvested. Samples were analyzed for RNA, DNA, and protein content, cell proliferation, and vascularity. Where interactions were present (P ≤ 0.05), least squares means from the highest-order interaction are presented.Results
Final body weight of ewes was least (P ≤ 0.002) in RES, intermediate for CON, and greatest for EXC, regardless of stage of the ewe at necropsy (parturition or d 20 of lactation). In ewes necropsied at parturition, mammary glands were heavier (P = 0.02) in EXC compared to RES, with CON intermediate. Concentration of RNA (mg/g) was decreased (P = 0.01) in EXC compared to CON at parturition. There was a tendency (P = 0.07) for a Se by nutrition interaction in percentage of cells proliferating where ASe-EXC ewes had greater (P ≤ 0.02) number of proliferating cells then all other treatments. Mammary vascular area tended (P = 0.08) to be affected by a Se by nutrition interaction where ASe-CON had less (P = 0.007) vascular area than HSe-CON ewes. In ewes necropsied at d 20 of lactation, the number of alveoli per area was decreased (P ≤ 0.05) in RES compared to CON and EXC-fed ewes.Conclusions
Results of this study indicate that proper maternal nutritional plane during gestation is important for mammary gland development, even out to d 20 of lactation. 相似文献38.
Pawel T. Szymanski Pratik Muley Safwat A. Ahmed Sherief Khalifa Hesham Fahmy 《Marine drugs》2012,10(10):2166-2180
Sarcophine-diol (SD) is a semi-synthetic derivative of sarcophine with a significant chemopreventive effect against non-melanoma skin cancer both in vitro and in vivo. Recently, we have studied the effect of SD on melanoma development using the mouse melanoma B16F10 cell line. In this study, our findings show that SD suppresses cell multiplication and diminishes membrane permeability for ethidium bromide (EB), a model marker used to measure cell permeability for Ca2+ ions. SD also decreases protein levels of COX-2, and increases degradation of phospholipases PLA2 and PLCγ1 and diminishes enzymatic activity of the Ca2+-dependent cPLA2. This lower membrane permeability for Ca2+-ions, associated with SD, is most likely due to the diminished content of lysophosphosphatidylcholine (lysoPC) within cell membranes caused by the effect of SD on PLA2. The decrease in diacylglycerol (DAG) and inositol 1,4,5-triphosphate (IP3) due to inhibition of PLCγ1, leads to the downregulation of Ca2+-dependent processes within the cell and also inhibits the formation of tumors. These findings support our previous data suggesting that SD may have significant potential in the treatment of melanoma. 相似文献
39.
40.
Hundred-and-two samples of four kinds of mild replacers for calves, produced in Czechoslovakia, were examined and evaluated. None of the studied pathogenic germs was detected in the samples. More than a half of the samples contained 1000 and 10000 mesophilous germs per 1 g. More than a third contained 1 to 1000 coliform germs per 1 g. On the basis of the results it is recommended--within microbiological requirements for the product--to propose that the maximum total number of microorganisms should be 100000 per 1 g of product. 相似文献