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151.
Rafael Rodríguez-Martínez Oscar Ángel-García Juan Manuel Guillén-Muñoz Pedro Antonio Robles-Trillo Maria de los Angeles De Santiago-Miramontes Cesar Alberto Meza-Herrera Miguel Mellado Francisco Gerardo Véliz 《Tropical animal health and production》2013,45(4):911-915
A trial was conducted during the anestrous period in female goats to determine: (a) whether estrus can be induced in anestrous goats by administration of equine chorionic gonadotropic hormone (eCG) and PGF2α under pen conditions and (b) whether these sexually active female goats can elicit sexual arousal in sexually inactive bucks. One hundred and fifteen pluriparous, nonlactating mixed-breed female goats were randomly assigned to one of four treatment groups: (1) administration of a single dose of 240 IU of eCG, 50 μg PGF2α i.m., and 25 mg progesterone (P4) (eCG; n?=?30); (2) administration of P4 and exposure to female goats treated with eCG–PGF2α (P4; n?=?39); (3) administration of 0.5 ml saline and P4 (Sal; n?=?23); and (4) P4 plus exposure to female goats treated with saline (Con; n?=?23). After hormone administration, all goats were put together with adult sexually inactive bucks for 15 days. The percentage of goats in estrus during these 15 days was similar in eCG-treated animals and untreated animals exposed to the eCG animals (97 and 95 %). Pregnancy rate was also similar (63 vs. 64 %) between these two groups. eCG-treated goats exhibited estrus earlier (P?<?0.05) than the treated goats in contact with the eCG goats. Furthermore, eCG-treated goats had larger litters (1.9?±?0.2 vs. 1.6?±?0.1, P?<?0.05) than the untreated goats in contact with the eCG goats. These results show that fertile estrus can be induced in anestrous female goats by exposing them to female goats induced to estrus with eCG. This female–female interaction triggers the stimulation cycle leading to the sexual arousal of bucks. 相似文献
152.
The absolute quantities and the stereoisomeric ratios of R, S-2-hydroxybutanone and R, R-, S, S-, R, S ( meso)-2,3-butanediol were determined in batteries of traditional balsamic vinegar (TBV) by gas chromatography-mass spectrometry (GC-MS), using a chiral capillary column, to evaluate if such parameters could be used to differentiate TBV differently aged and from different producers. Results showed that the initial amounts of 2-hydroxybutanone and 2,3-butanediol were quite variable, as a function of the producer of the vinegar; moreover, the 2-hydroxybutanone amount decreased during aging while 2,3-butanediol increased. Initially, the R-2-hydroxybutanone form prevails, and then the R/ S ratio decreased regularly during aging with some exceptions attributed to the addition of new barrels during the battery management. With regard to the 2,3-butanediol isomers, the most abundant was the R, R form, slowly transformed into the R, S and S, S isomers during aging. The GC-MS method used is easy and fast and could allow for a quick control of the maturation level of the vinegar. 相似文献
153.
Gerardo A. Belandria Michael M. Pavletic James P. Boulay Dominique G. Penninck Leslie A. Schwarz 《The Canadian veterinary journal. La revue veterinaire canadienne》2009,50(7):733-740
Surgical stapling equipment was used to create a gastropexy in 20 dogs undergoing
emergency surgery for gastric dilatation and volvulus (GDV). The technique
involved creation of a tunnel between the seromuscular layer and the submucosa
of the pyloric antrum, and a matching tunnel beneath the right m. transversus
abdominis. The arms of a gastrointestinal anastomosis stapling device were
introduced into the tunnels, and the device was fired to create the gastropexy.
One dog died of systemic sequelae of GDV during the early postoperative period.
None of the remaining 19 dogs developed a recurrence of GDV during follow-up
periods ranging from 5 to 43 months. In 11 dogs, the integrity of the gastropexy
was evaluated by abdominal ultrasonography and either negative contrast
gastrography or double contrast gastrography; in these dogs, the radiographic
and/or the ultrasonographic findings were suggestive of an intact gastropexy.
There were no complications involving the gastropexy staple line. The results of
this study indicate that an effective and consistent permanent gastropexy can be
created, using surgical stapling equipment. 相似文献
154.
Root morphological traits related to phosphorus‐uptake efficiency of soybean,sunflower, and maize
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Many of the plant acquisition strategies for immobile nutrients, such as phosphorus (P), are related to the maximization of soil exploration at minimum metabolic cost. Previous studies have suggested that soybean (Glycine max L.), sunflower (Helianthus annuus L.), and maize (Zea mays L.) differ in their P uptake efficiency. In this investigation we employed these three species to evaluate: (1) the effect of suboptimal P conditions on root morphological traits related to root porosity and fineness and (2) how these traits are related to P‐uptake efficiency. Opaque 25‐L plastic containers were used to grow plants hydroponically. The three species were compared under two P availability levels (low P and high P). Most of the observed responses were in the direction to favor P uptake under low‐P conditions. Compared to P‐sufficient plants, P‐stressed plants of the three species showed higher root‐to‐shoot ratio, specific root length, root porosity and root aerenchyma, and a lower root density. For example, P‐stress increased root porosity by a factor of 2.0, 1.4, and 1.4 in soybean, sunflower, and maize, respectively. Soybean and sunflower were the species with the highest P‐uptake efficiency, expressed as P uptake either per unit root biomass or length. The results demonstrate the central role of aerenchyma development in modifying root length per unit root biomass and, thus, reducing the root's foraging costs. Consequently, aerenchyma is suggested to be a possible mechanism for better P‐uptake efficiency. 相似文献
155.
156.
Gerardo Iglesias Carlos Pijoan Thomas Molitor 《Comparative immunology, microbiology and infectious diseases》1992,15(4):249-259
Alveolar macrophages (AM) infected with Pseudorabies virus (PRV) were compared to noninfected AM for cytotoxicity against foreign or transformed cells and production of interferon (IFN). Five PRV strains were used to infect AM including strains that are known to be highly virulent for pigs, i.e. strain 4892 and strain S-62 as well as strains that are regarded as mild or nonvirulent, i.e. BUK and Bartha. The multiplicity of infection ranged from 0.005 to 0.05 TCID50/cell. The target cells in the cytotoxicity assays were either chicken red blood cells, PRV-infected vero cells, or human myeloblastoma cells (K562 cell line). For the producton of IFN, AM cultures were treated with polyinosinic: polycytidylic acid (Poly I:C) diluted in tissue culture media at a concentration of 5 μg/106 cells. Culture supernatants were collected at various times poststimulation and tested for antiviral activity using the Vesicular Stomatitis Virus replication inhibition test. Swine AM were able to lyse chicken red blood cells in an antibody-independent way but not in an antibody-dependent way, whereas lysis of PRV-infected vero cells was accomplished both ways. The cytotoxicity against chicken red blood cells was reduced in the PRV-infected AM as compared to noninfected cells, particularly in AM infected with virulent PRV strains. Specific 51Cr release values for AM infected with S-62 and 4892 strains were 14 and 19, while the noninfected AM had values of 36. Similarly, in the antibody-dependent cytotoxicity assay against PRV-infected vero cells there was no activity of AM against K562 cells. The production of IFN was readily stimulated with Poly I:C. The optimal time for supernatant collection was between 12 and 16h poststimulation. The antiviral activity was abrogated by treatment of the supernatant with antiserum against human leukocyte IFN; it was therefore considered to be due to interferon-alpha (IFN) released from the macrophages. The antiviral activity present in supernatants of PRV-infected AM was reduced compared to noninfected AM. The difference between AM cultures infected with virulent strains of PRV and noninfected AM cultures was statistically significant at P 0.025. The results provide support to the premise that the role of AM in lung defense can be compromised by PRV infection. 相似文献
157.
Blanca Estela Gómez-Luna Ma. Cruz Rivera-Mosqueda Luc Dendooven Gerardo Vázquez-Marrufo Víctor Olalde-Portugal 《Applied soil ecology》2009,41(1):50-58
Temperate forests dominated by Quercus spp. cover large parts of Central Mexico and rural communities depend on these forests for wood and charcoal. The impacts of charcoal production on selected chemical properties including C and N dynamics, and populations of ammonifiers, nitrifiers and denitrifiers were investigated on surface soils (0–15 cm) collected during the dry and rainy season of these forests. Organic C was halved in soil at the kiln sites compared to undisturbed forest soil. Concentrations of exchangeable Ca2+, K+ and Mg2+ increased >1.6 times at kiln sites and pH increased from 4.5 in undisturbed soil to 7.0 at kiln sites. The kiln sites had 1.3 times and 2.4 times lower microbial biomass C and N, respectively, than undisturbed forest sites during the rainy season. Although the effect of charcoal production on NH4+, NO2? and NO3? concentrations was small, the ammonifying, nitrifying and denitrifiers were 16 times lower at the kiln sites than in the undisturbed forest soil. This research found that the charcoal production had a negative effect on the cultivable microorganisms involved in N cycling and the soil microbial biomass C and N compared to undisturbed forest soil. Differences in inorganic N dynamics were more affected by seasonality, i.e. precipitation, than by charcoal production. 相似文献
158.
Germana Esposito Roberta Teta Roberta Miceli Luca S. Ceccarelli Gerardo Della Sala Rosa Camerlingo Elena Irollo Alfonso Mangoni Giuseppe Pirozzi Valeria Costantino 《Marine drugs》2015,13(1):444-459
The study of the secondary metabolites contained in the organic extract of Caribbean sponge Smenospongia aurea led to the isolation of smenothiazole A (3) and B (4), hybrid peptide/polyketide compounds. Assays performed using four solid tumor cell lines showed that smenothiazoles exert a potent cytotoxic activity at nanomolar levels, with selectivity over ovarian cancer cells and a pro-apoptotic mechanism. 相似文献
159.
160.
Carlos A. Cruz-Cruz Gerardo Ramírez-Tec Karlina García-Sosa Fabiola Escalante-Erosa Lionel Hill Anne E. Osbourn Luis M. Peña-Rodríguez 《European journal of plant pathology / European Foundation for Plant Pathology》2010,126(4):459-463
The previously detected antifungal activity against Mycosphaerella fijiensis of aqueous infusions of healthy banana (Musa acuminata cv. Grande Naine) leaves, suggested the production of phytoprotectants by the plant. The bioassay-guided VLC-purification
of the lyophilized infusion of the leaves of 4-month old healthy banana (M. acuminata cv. Grande Naine) plants, resulted in the purification of a phytoanticipin with strong antifungal activity against M. fijiensis Morelet, the causal agent of black Sigatoka, the most destructive and devastating disease of bananas and plantains in the
world. The LC-MS analysis of the purified phytoanticipin suggests a steroidal saponin structure with four sugar units attached
to the C-3 position of a diosgenin-like aglycone. This represents the first report of phytoanticipins occurring in M. acuminata. 相似文献