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131.
132.
Miguel González-Lozano Daniel Mota-Rojas E. Yadira Velázquez-Armenta Alejandro A. Nava-Ocampo Rafael Hernández-González Marcelino Becerril-Herrera María E. Trujillo-Ortega María Alonso-Spilsbury 《The Canadian veterinary journal. La revue veterinaire canadienne》2009,50(12):1273-1277
Sixty hybrid Yorkshire-Landrace penned sows, 30 with eutocic farrowing and 30 experiencing a dystocic parturition, were studied to evaluate the obstetric and neonatal outcomes to low doses of oxytocin administered at advanced stages of parturition. Animals in each group were randomly subdivided into 2 subgroups: 15 eutocic and 15 dystocic sows received oxytocin 0.083 IU/kg (equivalent to 1 IU/12 kg body weight), administered intramuscularly after the delivery of the 5th piglet; the other 15 eutocic and 15 dystocic sows received saline solution intramuscularly at the same time. Oxytocin decreased the number of intrapartum deaths by approximately 50% (P = 0.002). No piglet was born dead from the saline- and oxytocin-treated eutocic sows. The highest viability score was observed among piglets born to eutocic sows treated with oxytocin. In summary, this dose schedule would help to decrease the number of stillbirths in both eutocic and dystocic farrowing sows. 相似文献
133.
ASSESSING CIRCLE OF WILLIS BLOOD CIRCULATION IN DOGS WITH TRANSCRANIAL COLOR-CODED DUPLEX SONOGRAPHY
Francisco J. Duque Jose M. Dominguez-Roldan Patricia Ruiz Concepcion Zaragoza Rafael Barrera-Chacon 《Veterinary radiology & ultrasound》2009,50(5):530-535
Insonation of Circle of Willis by transcranial Doppler duplex color sonography is described in 30 healthy dogs with 15 weighing <33 lb and 15 weighing >33 lb. Imaging was via a temporal window to explore the rostral, middle, and caudal cerebral arteries on both the left and right-hand sides; and through an suboccipital window to study the basilar artery. Normal mean values of the peak systolic velocity (PSV), end diastolic velocity, mean velocity, resistance index (RI), and pulsatility index (PI) were characterized and compared with those obtained in previous studies. There was significant differences in the PSV, RI, and PI in the rostral cerebral artery between dogs weighing <33 vs. >33 lb. Mean PSV was higher in weighing over 33 lb, whereas the mean resistive index and mean PI were lower in these dogs. 相似文献
134.
Nadia Korolev Encarnación Pérez-Artés Jesús Mercado-Blanco José Bejarano-Alcázar Dolores Rodríguez-Jurado Rafael M. Jiménez-Díaz Talma Katan Jaacov Katan 《European journal of plant pathology / European Foundation for Plant Pathology》2008,122(4):603-617
Verticillium dahliae isolates recovered from a new focus of severe Verticillium wilt of cotton in the northeast of Israel were tested for vegetative
compatibility using nitrate non-utilizing (nit) mutants and identified as VCG1, which is a new record in Israel. Other cotton isolates of V. dahliae from the northern and southern parts of the country were assigned to VCG2B and VCG4B, respectively. VCG1 isolates induced
severe leaf symptoms, stunting and defoliation of cotton cv. Acala SJ-2, and thus were characterized as the cotton-defoliating
(D) pathotype, whereas isolates of VCG2B and VCG4B were confirmed as the earlier described defoliating-like (DL) and non-defoliating
(ND) pathotypes, respectively. This is the first record of the D-pathotype in Israel. The host range of representative isolates
of each VCG-associated pathotype was investigated using a number of cultivated plants. Overall, the D isolates were more virulent
than DL isolates on all tested host plants, but the order of hosts (from highly susceptible to resistant) was the same: okra
(Hibiscus esculentus local cultivar), cotton (Gossypium hirsutum cv. Acala SJ2), watermelon (Citrullus lanatus cv. Crimson Sweet), safflower (Carthamus tinctorius cv. PI 251264), sunflower (Helianthus annuum cv. 2053), eggplant (Solanum melongena cv. Black Beauty), and tomato (Lycopersicon esculentum cv. Rehovot 13). The pattern of virulence of ND isolates differed from that of D and DL isolates, so that the former were
highly virulent on eggplant but mildly virulent on cotton. Tomato was resistant to all cotton V. dahliae isolates tested. RAPD and specific PCR assays confirmed that the D isolates from Israel were similar to those originating
from other countries. 相似文献
135.
Caique Carvalho Medauar Samuel de Assis Silva Luis Carlos Cirilo Carvalho Rafael Augusto Soares Tibúrcio Julião Soares de Souza Lima Paullo Augusto Silva Medauar 《Journal of Sustainable Forestry》2018,37(7):739-752
This study evaluated the effectiveness of chemical control for eradicating eucalyptus sprouts using images obtained with Unmanned Aerial Vehicle (UAV). The study was carried out in eucalyptus plantations in Itabela, BA, in replanting areas during pre-planting application of herbicide. Aerial images obtained by a UAV were used to evaluate the effectiveness of the herbicide application for sprouts control. After the images were acquired, they were processed to calculate the normalized difference vegetation index (NDVI) and submitted to a supervised classification to quantify the percentage reduction of sprout green matter. The percentage data were submitted to analysis of variance and the means were compared by Tukey test at 5%. The differences, both visual and average percentages were observed only during the evaluation period with no evident effect of the treatments on sprout control. The images provided by the UAV allowed to monitor and identify visually the plots where biomass reduced or increased and to evaluate the effectiveness of chemical control of eucalyptus sprouts, indicating areas where it was nonexistent, partial or total. 相似文献
136.
Carolina Reigada Rafael de Andrade Moral Clarice Garcia Borges Demétrio José Roberto Postali Parra 《Journal of pest science》2018,91(1):121-131
The cotton bollworm Helicoverpa armigera is a destructive pest that affects a variety of crop plants. Because of its polyphagous feeding habit, mobility as adults, and high fecundity, the expanding infestations of H. armigera in different crops have caused economic losses and difficulties for pest population management. In Brazil, a sequence of different crop systems in the same area and crop rotation during the year can create a spatio-temporal mosaic of crops where H. armigera can persist. However, the consequences of the simultaneous and/or alternating presence of host plants for H. armigera populations through generations are unknown. In this study, we simulated, in the laboratory, hypothetical situations for the availability of soybean and cotton crops in the landscape. We evaluated the effects of: (1) the number of generations during which a population feeds on a host-plant species; (2) the succession of host-plant species on which populations have fed for two generations; and (3) the parental host plant on the fitness of H. armigera populations. Only the current host plant on which larvae fed affected the performance of the H. armigera populations. Decrease of mortality rates during the immature period was slowed when the larvae fed on soybean. The lowest value of reproductive potential (R 0) was found for individuals originating from mating between females and males reared in cotton. Our results indicated that pest-management and biological-control plans for H. armigera should be developed on a regional scale rather than for just a specific crop area. 相似文献
137.
Marcos Rafael Nanni Everson Cezar Guilherme Fernando Capristo Silva Anderson Antonio da Silva Gualberto 《Archives of Agronomy and Soil Science》2018,64(5):682-695
New techniques and improvements are required to quantify soil’s chemical and physical properties on production environment, reducing environmental impacts and minimizing soil analysis time. The aim of this study is to evaluate the possibility to estimate the content of silt, sand, clay, total iron and organic matter in soils formed by different lithologies in Parana State, Brazil, using VIS-NIR spectrum associated with Partial Least Square Regression (PLSR). 200 soil samples were collected in an area formed by Lixisols, Cambisols, Ferralsols, Arenosols and Nitisols in a depths of 0–0.2 and 0.2–0.8 m. Spectral readings were obtained in laboratory by FieldSpec 3 JR sensor. The spectral curves of the samples were correlated to the attributes through PLSR. The results obtained for sand in prediction were better when compared to the other attributes, presenting R2 = 0.90, r = 0.95 and RPD = 2.3. Clay and total iron presented satisfactory results, mainly for RPD values, which were above 2.4. Based on the results, it can be concluded that the PLSR technique associated with the spectral response of the soils, was able to estimate sand, clay and total iron with accuracy in a region formed by reworked materials, derived from several lithologies. 相似文献
138.
Patricia C. Duarte Cahuê F.R. Paz Alvaro P.L. Oliveira Thairê P. Maróstica Leticia O. Cota Rafael R. Faleiros 《Veterinary anaesthesia and analgesia》2017,44(4):943-950
Objective
To investigate the nociceptive and clinical effects of buffering a lidocaine–epinephrine solution with sodium bicarbonate in caudal epidural block in mares.Study design
Prospective randomized controlled trial.Animals
Six mixed-breed mares weighing 350–440 kg.Methods
Each animal was administered two caudal epidural injections, 72 hours apart, using different solutions prepared immediately before injection. The control solution was 7 mL 2% lidocaine hydrochloride with epinephrine hemitartrate (1:200,000) added to 3 mL sterile water for injection (pH 2.9). The alkalinized solution was 7 mL of lidocaine–epinephrine solution added to 2.3 mL sterile water for injection and 0.7 mL 8.4% sodium bicarbonate (pH 7.4). Nociception was evaluated by response to skin pinching at 31 sites in the sacral region and around the perimeter of the anogenital area (distances of 10, 15 and 20 cm) before, and 5, 10 and 15 minutes after epidural injection, then every 15 minutes until the return of nociception in all evaluated sites. The onset and duration times, and intensity of ataxia (grades 0 to 3) were recorded. The paired t test was used to compare the onset and duration of anesthesia and ataxia (p < 0.05).Results
Alkalization of the solution resulted in significant decreases in the average time of onset of loss of nociception in the sacral region (40%) and around the perimeter of the anogenital area extending up to 5 cm (36%) and from 5 to 10 cm (32%) from the anus and vulva. Alkalization also decreased the average duration of ataxia (33%), without affecting the duration and extent of anesthesia or the degree of ataxia.Conclusions and clinical relevance
Alkalization of lidocaine–epinephrine solution is advantageous in shortening the duration of ataxia and hastening the onset of anesthesia in areas adjacent to the anogenital area, without reducing the duration of epidural anesthesia, in mares. 相似文献139.
Evaluation of reticulocyte hemoglobin content (RET‐He) in the diagnosis of iron‐deficient erythropoiesis in dogs 下载免费PDF全文
Jannika Fuchs Andreas Moritz Esther Grußendorf Jörg Lechner Felix Neuerer Rafael Nickel Thomas Rieker Claudia Schwedes Dennis B. DeNicola James Russell Natali Bauer 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2017,46(4):558-568
Background
Reticulocyte hemoglobin content provided by the Siemens ADVIA (CHr) is an established marker of iron deficiency. The IDEXX ProCyte Dx hematology analyzer now provides a similar variable, reticulocyte hemoglobin equivalent (RET‐He).Objectives
The objective was to evaluate RET‐He and its diagnostic utility in dogs, and to calculate a cutoff value for diagnosing iron‐deficient erythropoiesis (IDE). Furthermore, the prevalence of RET‐He values below this cutoff value was established.Methods
One hundred and seventy‐one CBCs of healthy dogs were used to establish a RI. Stability of RET‐He was evaluated by repeated measurements over 48 hours (n = 10). The 25‐run coefficient of variation (CV) was calculated, and correlation and bias between measurements of RET‐He and CHr were assessed (n = 190). A cutoff value for diagnosing IDE was calculated. The utility of RET‐He in the detection of IDE was evaluated in 123 dogs. The prevalence of low RET‐He values was assessed retrospectively in a multicenter study (2012–2014) under participation of 7 veterinary clinics.Results
Reticulocyte hemoglobin equivalent with an RI of 22.2 to 28.6 pg was statistically stable over 48 hours (P = .10). The CV was 1.8%. A fair correlation (ρ = 0.74) between RET‐He and CHr with a small bias of ?0.6 pg was found. The cutoff value for diagnosing IDE was 20.9 pg (sensitivity: 85%; specificity: 99%). The prevalence of RET‐He values below 20.9 pg was 10.3% (1084/10,553 dogs).Conclusions
RET‐He on the ProCyte Dx is a precise screening tool in dogs to detect iron‐deficient erythropoiesis. 相似文献140.
Gerardo Ordaz-Ochoa Aureliano Juárez-Caratachea Rosa Elena Pérez-Sánchez Rafael María Román-Bravo Ruy Ortiz-Rodríguez 《Tropical animal health and production》2017,49(5):1025-1033
The effect of spineless cactus intake (Opuntia ficus-indica) on blood glucose (BG) levels in lactating sows and its impact on daily and total feed intake (dFI?1 and TFI, respectively), body weight loss (BWL), and weaning-estrus interval length (WEI) were evaluated. Thirty-four hybrid (Yorkshire × Landrace × Pietrain) sows in lactation phase were used. Sows were divided into two groups: G1 (n = 17) where they received commercial feed and G2 (n = 17) provided with commercial feed plus an average of 2.0 ± 0.5 kg spineless cactus, based on a sow’s body weight. The variables evaluated were BG, dFI?1, TFI, BWL, and WEI. Statistical analysis was performed by using a fixed and mixed model methodology, under a repeated measurements experiment. Group effects were found on all analyzed variables (P < 0.05). The BG was lower in G2 (55.2 and 64.5 mg/dL pre- and post-prandial, respectively), compared to that in G1 (70.9 and 80.1 mg/dL pre- and post-prandial, respectively) (P < 0.05). G2 showed better performance than G1 for dFI?1, BWL, and WEI (P < 0.05) whose averages were 5.5 ± 1.8 kg, 7.4 ± 4.5%, and 5.3 ± 1.2 days, respectively. Averages for these variables in G1 were 4.7 ± 1.5 kg, 16.8 ± 4.6%, and 6.1 ± 1.6 days, respectively. Intake of spineless cactus reduced BG levels in lactating sows, generating greater dFI?1, lower BWL at the end of lactation, and a lower WEI. 相似文献