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101.
Luca Godoi Santana Rocha Daniel Jordan Abreu dos Santos Humberto Tonhati Raphael Bermal Costa Gregrio Miguel Ferreira de Camargo 《Reproduction in domestic animals》2019,54(5):808-811
The information of twin pregnancy frequencies in buffaloes is scarce in the literature. Evidence even indicates that twin pregnancies are not carried to term, but it does not seem to be the case. In this case report, the event of twin pregnancy in buffaloes is reported as well as its frequency. Twin birth is the presence of two or more embryos in a single gestation. Multiple births are uncommon in buffaloes since the species is uniparous. We studied a population of Murrah buffaloes in which slightly more than 13,000 births were observed. In this study, the frequency of occurrence of twin births in Murrah buffaloes was 0.14%. This low incidence impaired the estimation of genetic parameters. Twins can have advantages and disadvantages depending on the production system, which are discussed in this case report. 相似文献
102.
103.
Mechanistic target of rapamycin is activated in bovine granulosa cells after LH surge but is not essential for ovulation
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PRA da Rosa AMP Dau MP De Cesaro JT dos Santos BG Gasperin R Duggavathi V Bordignon PBD Gonçalves 《Reproduction in domestic animals》2016,51(5):766-773
The LH surge induces functional and morphological changes in granulosa cells. Mechanistic target of rapamycin (mTOR) is an integrator of signalling pathways in multiple cell types. We hypothesized that mTOR kinase activity integrates and modulates molecular pathways induced by LH in granulosa cells during the preovulatory period. Cows were ovariectomized and granulosa cells collected at 0, 3, 6, 12 and 24 hr after GnRH injection. While RHEB mRNA levels increased at 3 and 6 hr, returning to basal levels by 12 hr after GnRH treatment, RHOA mRNA levels increased at 6 hr and remained high thereafter. Western blot analyses revealed increased S6K phosphorylation at 3 and 6 hr after GnRH injection. Similarly, mRNA levels of ERK1/2, STAR and EGR‐1 were higher 3 hr after GnRH treatment. Rapamycin treatment inhibited mTOR activity and increased AKT activity, but did not alter ERK1/2 phosphorylation and EGR1 protein levels in cultured bovine granulosa cells. Rapamycin also inhibited LH‐induced increase in EREG mRNA abundance in granulosa cells in vitro. However, intrafollicular injection of rapamycin did not suppress ovulation. These findings suggest that mTOR is involved in the control of EREG expression in cattle, which may be triggered by LH surge stimulating RHEB and S6K activity. 相似文献
104.
Fabio Rossi Cavalcanti Mario Lucio Vilela Resende Joo Paulo Matos Santos Lima Joaquim Albenisio Gomes Silveira Jos Tadeu Abreu Oliveira 《Physiological and Molecular Plant Pathology》2006,68(4-6):198-208
The activities of antioxidant enzymes and photosynthetic responses were investigated in tomato (Lycopersicon esculentum L. var.) pre-treated by plant activators and inoculated by Xanthomonas vesicatoria. Plants were sprayed with acibenzolar-S-methyl, ASM [Bion® 50 WG (0.2 g l−1)] and aqueous extract from dry necrotic tissue flour (VLA) of ‘Lobeira’ (Solanum lycocarpum) bush. Four days later, the plants were challenged with a virulent strain of X. vesicatoria, under greenhouse conditions. Tomato leaves were then assessed to determine the activities of the main antioxidant enzymes: superoxide dismutase (SOD), catalase (CAT), peroxidase (POX), and ascorbate peroxidase (APX). A reduction of bacterial leaf spot severity was observed in plants treated by ASM (49.3%) and VLA (31.4%), without any in vitro inhibitory activity over the pathogen. Controls showed decreases in CO2 assimilation, transpiration, photosynthetic rates, and stomatal conductance. Water use efficiency and carboxylation efficiency were strongly affected in ASM- and VLA-treated, in comparison to controls and healthy plants. The tested substances induced increases in SOD and CAT activities in a delayed enzymatic response typical in compatible plant–pathogen interactions. Measured at daily intervals, activities of APX and POX were significantly (ρ0.05) higher in treated plants than in controls, except for APX in ASM-treated plants where no difference was found when compared to controls. Only POX was clearly induced at the earlier stages after spraying the tomato plants with ASM or VLA. Our results suggest that late increases in antioxidant enzyme activities may play a role in mitigating oxidative damage in restoring the photosynthetic imbalance imposed by the expansion of bacterial lesions. 相似文献
105.
Eileen Azevedo Santos Margarete Magalhães Souza Priscilla Patrocínio Abreu Leo Duc Haa Carson Schwartzhaupt da Conceição Ioná Santos Araújo Alexandre Pio Viana Alex-Alan Furtado de Almeida Jôsie Cloviane de Oliveira Freitas 《Euphytica》2012,184(3):389-399
Three new varieties of Passiflora hybrids were developed from crosses between P. sublanceolata J. M. MacDougal (ex P. palmeri var. sublanceolata Killip) versus P. foetida var. foetida L. Twenty putative hybrids were analyzed. Hybridizations were confirmed by RAPD and SSR markers. The RAPD primer UBC11 (5′-CCGGCCTTAC-3′)
generated informative bands. The SSR primer A08FP1 amplified species-specific fragments and heterozygote status was observed
with the two parent bands 240 and 280 bp. The molecular markers generated by primers were analyzed in terms of the presence
or absence of specific informative bands. The morphological characterization of the hybrids enabled their differentiation
into three groups, identified as: (1) Passiflora ‘Alva’, composed of five hybrid plants with white flowers, large corona, light purple filaments at base, white and purple/white
banding to apex; (2) P. ‘Aninha’, composed of six hybrid plants with pale pink flowers, corona filaments reddish/purple at base, white, purple/white
banding to apex; (3) P. ‘Priscilla’, composed of nine hybrid plants with white flowers, small corona, filaments dark purple at base, white and purple
to apex. The genomic homology of parent plants was verified by cytogenetic analysis. Both parents were 2n = 22. Meiosis was regular in genitors and hybrids. Aneuploidy was observed at hybrid groups P. ‘Alva’ and P. ‘Priscilla’ (2n = 20). Other authors had already observed the same number of chromosomes for some P. foetida genotypes. Obtaining valuable interspecific hybrids opens up new perspectives to offer opportunities in agribusiness for
producers and to arouse the interest of consumers into using passion flowers in the Brazilian ornamental plant market. 相似文献
106.
Miguel . A. Pinheiro de Carvalho Jan J. Slaski Ivo Abreu Filipe T. Ganana Teresa M. M. dos Santos Lurdes Freitas Maria R. Clemente Vieira Antonieta Nunes Ana Domingues Gregory J. Taylor 《植物养料与土壤学杂志》2004,167(1):93-98
Forty genotypes representing maize genetic diversity from the Island of Madeira were screened for resistance to aluminum (Al) in nutrient solution. Seeds of maize were obtained from local farmers from field plots spread around the island in a range of altitudes from 99 to 1000 m above sea level. The content of ionic aluminum and the pH of soils cultivated with maize were determined. The mean pH value of all examined soils was 4.9, while the mean ionic Al content was 0.76 cmol kg–1. Seventy‐two hours (h) exposure to 100 and 200 μM Al followed by a 48 h recovery period of 4‐day old seedlings revealed significant differences in Al resistance in the Madeiran maize germplasm. Root survival and regrowth exceeding 80 % of the seedlings were observed in 22 and 8 of the tested genotypes screened at 100 and 200 μM Al in nutrient solution. High Al resistance among Madeiran maize genotypes appeared not to be associated with the lower pH of soil, and did not correlate with the amount of soil Al3+ or the altitude at the site of collection. The high level of Al resistance of the maize cultivars indicates an initial genetic trait enhanced by open pollination of maize. 相似文献
107.
108.
Serological response to Actinobacillus pleuropneumoniae serovar 7 infection in a commercial pig herd
IA GARDNER JT BOSSɆ RF SHELDRAKE† S ROSENDAL† RP JOHNSON§ 《Australian veterinary journal》1991,68(11):349-352
Serological responses to Actinobacillus pleuropneumoniae serovar 7 infection were monitored by enzyme-linked immunosorbent assay in a cohort of 66 pigs between weaning and market. Antibody concentrations were high (63/65 seropositive) at 4 weeks of age but declined to low levels from 8 to 12 weeks. Mean antibody concentrations rose significantly (p less than 0.001) between 12 and 23 weeks. Between 8 and 23 weeks of age, 33 (51.5%) of 64 surviving pigs seroconverted to A pleuropneumoniae serovar 7. Peak antibody concentrations in the seroconverting pigs usually (28/33) occurred at 23 weeks. Seroconversion to A pleuropneumoniae during the grower/finisher phase was not significantly associated (p greater than 0.05) with passive antibody concentrations at 4 weeks of age, lack of vaccination against Mycoplasma hyopneumoniae, or weaning weight. Pleuropneumonic lesions were evident at slaughter in 4 (6.3%) of 64 pigs. A pleuropneumoniae serovar 7 was isolated from 2 of 4 lungs with pleuropneumonia and from another lung with lesions considered typical of enzootic pneumonia. 相似文献
109.
In a pen feeding trial fresh Echium plantagineum was fed as the sole diet to crossbred sheep with or without a history of previous access to the plant. Control groups received a diet of lucerne chaff and oats. During the trial, sheep on the Echium diet lost weight and deaths occurred with histological evidence of excessive copper accumulation, usually accompanied by pyrrolizidine alkaloid damage, in the liver and biochemical evidence of liver toxicity. It is concluded that E. plantagineum alone is not a suitable fodder for sheep and can be toxic due to its pyrrolizidine alkaloid content and high copper to molybdenum ratio. 相似文献
110.
Grant JK Abreu FM Hojer NL Fields SD Perry BL Perry GA 《Journal of animal science》2011,89(11):3531-3541
At the initiation of most controlled internal drug-releasing (CIDR) device protocols, GnRH has been used to induce ovulation and reset follicular waves; however, its ability to initiate a new follicular wave is variable and dependent on stage of the estrous cycle. The objectives of the current studies were to determine 1) if inducing luteal regression before the injection of GnRH at time of insertion of a CIDR resulted in increased control of follicular development, and 2) if removing endogenous progesterone by inducing luteal regression before insertion of the CIDR decreased variation in LH pulse frequency. In Exp. 1 and 2, Angus-cross cycling beef heifers (n = 22 and 38, respectively) were allotted to 1 of 2 treatments: 1) heifers received an injection of PGF(2α) on d -3, an injection of GnRH and insertion of a CIDR on d 0, and a PGF(2α) injection and CIDR removal on d 6 (PG-CIDR) or 2) an injection of GnRH and insertion of a CIDR on d 0 and on d 7 an injection of PGF(2α) and removal of CIDR (Select Synch + CIDR). In Exp. 3, Angus-cross beef heifers (n = 15) were assigned to 1 of 3 treatments: 1) PG-CIDR; 2) PGF(2α) on d -3, GnRH on d 0, and PGF(2α) on d 6 (PG-No CIDR); or 3) Select Synch + CIDR. Follicular development and ovulatory response were determined by transrectal ultrasonography. Across all experiments, more (P = 0.02) heifers treated with PG before GnRH initiated a new follicular wave after the injection of GnRH compared with Select Synch + CIDR-treated heifers. In Exp. 1, after CIDR removal, interval to estrus did not differ (P = 0.18) between treatments; however, the variance for the interval to estrus was reduced (P < 0.01) in PG-CIDR heifers compared with Select Synch + CIDR heifers. In Exp. 3, there was a tendency (P = 0.09) for LH pulse frequency to be greater among PG-CIDR and PG-No CIDR compared with the Select Synch + CIDR, but area under the curve, mean LH concentrations, and mean amplitude did not differ (P > 0.76). In summary, induction of luteal regression before an injection of GnRH increased the percentage of heifers initiating a new follicular wave. Removal of endogenous progesterone tended to increase LH pulse frequency, and the modified treatment increased the synchrony of estrus after CIDR removal. 相似文献