B-mode and M-mode echocardiography of endurance horses raised in São Paulo State, Brazil

This study aimed to evaluate cardiac dimensions and indexes of cardiac function in endurance horses using bidimensional- (B-) mode and guided unidimensional- (M-) mode echocardiography. Thirty-five Arabian and crossbred Arabian male and female horses, aged 5 to 18 years old, with an average weight of 415.51 ± 36.76 kg and at least 1 year of endurance training and competition experience, were used. The following values were obtained for B-mode echocardiography in the right parasternal window (see “Materials and Methods” for expanded terms): RVIDd 2.54 ± 0.56 cm; RVIDs 2.08 ± 0.68 cm; IVSd 2.60 ± 0.31 cm; IVSs 3.90 ± 0.44 cm; LVIDd 10.07 ± 0.85 cm; LVIDs 6.65 ± 0.92 cm; LVFWd 2.50 ± 0.30 cm; LVFWs 3.74 ± 0.35 cm; Aod 7.86 ± 0.72 cm; LAs 10.84 ± 0.93 cm; Vd 578.40 ± 108 cm³; Vs 232.68 ± 70.61 cm³; FS% 34.99% ± 8.02%; EF% 60.13% ± 8.29%; E-point 2.25 ± 0.49 cm; and LAs:Aod 1.38 ± 0.16 cm. Using guided M-mode, the following values were obtained: RVIDd 2.04 ± 0.55 cm; RVIDs 1.61 ± 0.71 cm; IVSd 2.68 ± 0.29 cm; IVSs 4.17 ± 0.42 cm; LVIDd 9.72 ± 0.72 cm; LVIDs 5.94 ± 0.96 cm; LVFWd 2.69 ± 0.32 cm; LVFWs 4.23 ± 0.69 cm; Aod 7.21 ± 0.75 cm; Vd 534.24 ± 87.53 cm³; Vs 181.75 ± 67.69 cm³; FS% 39.06% ± 7.66%; EF% 66.38% ± 9.41%; and E-point 1.96 ± 0.58 cm.

Introduction

In equine sports medicine, it is important to evaluate the cardiovascular condition of the athlete. More recently, echocardiography has been used for this purpose.Echocardiography is an invaluable diagnostic aid, since it is non-invasive and easy to perform,[1, 2 and 3] while offering a dynamic and functional evaluation of the heart. [2, 3, 4 and 5].Initially, studies on the M-mode were made, including measurements of normal cardiac dimensions in horses[6 and 7] and foals and for the diagnosis of several cardiac diseases. [1] With the introduction of the B-mode technique in the mid-1980s and its validation, a more detailed anatomic evaluation was possible, [2, 8 and 9] thus allowing the observation of cardiac abnormalities. [10]Though echocardiographic examination could be used to predict the athletic condition of individuals,[11] this is possible only if normal echocardiographic reference values are established. As different breeds have different biotypes and develop different aptitudes, it is necessary to provide enough information for each type of work or breed. Research includes data for the Thoroughbred racehorse [3, 12 and 13] and Standardbred trotter, [14 and 15] which perform essentially anaerobic work.The endurance race is a modality that is growing significantly in Brazil, both in number of participants and in quality and training of the animals. The endurance horse demands a physical conditioning that differs from that required for racehorses, especially owing to the development of aerobic work. In addition, the animals are mainly Arabian or Arabian crossbred, which have a particular biotype. Because of these facts, and the lack of data about the echocardiographic behavior of endurance horses, this study aimed to determine the dimensions and indexes of cardiac function for horses with endurance training using B-mode and guided M-mode echocardiography.

Materials and methods

Thirty-five clinically normal endurance Arabian and Arabian crossbred male and female horses between 5 and 18 years old, with an average weight of 415.51 ± 36.76 kg, were included in the study. All animals had at least 1 year of training and experience in competitions and were kept under similar hygienic, sanitary, and nutritional management. Training consisted of trail rides, alternating walking, trotting, and galloping, from 20 to 40 km per day, 3 to 4 times per week.The echocardiographic examination was performed with a Sonosite model 180 Plus v. 1.9 echocardiograph, using a 2-4–MHz electronic microconvex transducer with a maximal depth of 24 cm.The animals were prepared as previously reported,[4, 16 and 17] the hair being coated with large amounts of acoustic coupling gel. During the examination, the animals were at rest, calm, and physically restrained only by the halter, in a quiet and dark room.The following echocardiographic measurements, in B-mode as well as guided M-mode, were performed: the left atrium internal diameter in systole (LAs), only in B-mode, in the long axis view, dorsal to the annulus[15]; the right ventricle internal diameter, in diastole (RVIDd) and in systole (RVIDs); the interventricular septum thickness, in diastole (IVSd) and in systole (IVSs); the left ventricle internal diameter, in diastole (LVIDd) and in systole (LVIDs); and the left ventricle free wall thickness, in diastole (LVFWd) and in systole (LVFWs), from the left ventricle short axis view at the chordal level; and the aortic root internal diameter (Aod), from the aortic valve short axis view. The B-mode measurements were taken according to Patteson et al, [12] and the M-mode measurements were based on Long et al. [18]Images were obtained from the right hemithorax. The position used for the transducer to obtain the standardized images for B-mode and guided M-mode were determined and used as described in Reef.[4 and 17]The echocardiographic examination began using the B-mode echocardiography, with the establishment of the tomographic planes, evaluating morphology of the cardiac structures and their movement in a global manner.The first image obtained was the right parasternal long axis view, with the observation of the ventricle inlets, atrioventricular valves, and both atria. With the transducer positioned to optimize visualization of the left atrium, usually with a minimal dorsal angulation, the LAs measurement was made, immediately before the opening of the mitral valve (Fig 1).     

Diagnostic potential of natriuretic peptides in the occult phase of golden retriever muscular dystrophy cardiomyopathy

The objective of the study was to determine whether the plasma concentrations of atrial and brain natriuretic peptides (ANP and BNP, respectively) could be reliable markers of cardiac alterations during occult cardiomyopathy in Golden Retriever Muscular Dystrophy (GRMD). Fifty Golden Retrievers without any clinical or radiographic sign of heart disease were included in this study (21 GRMD dogs and 29 controls). Controls and GRMD dogs were divided into 2 subgroups according to age (< and > or =12 months old, respectively). All dogs underwent echocardiography and determination of BNP and ANP plasma concentrations by radioimmunoassay. No ventricular dilatation or dysfunction was observed in either control or GRMD dogs. ANP plasma concentration did not differ significantly between controls and GRMD dogs (mean +/- SD = 72 +/- 49 versus 58 +/- 23 pg/mL, respectively, P = .21). This finding was confirmed in both subgroups of dogs (ie, those < and > or =12 months old). In contrast, BNP plasma concentrations were significantly higher in GRMD dogs than in controls (mean +/- SD = 117 +/- 92 versus 46 +/- 22 pg/mL, respectively, P < .05). In dogs > or =12 months old, sensitivity and specificity of BNP for identifying GRMD with a cutoff of 65 pg/mL were 78 and 86%, respectively. For the same cutoff value, sensitivity dropped to 42%, whereas specificity reached 100% in dogs <12 months old. In conclusion, BNP may be a useful biochemical marker of asymptomatic cardiomyopathy. However, this peptide does not allow very early detection because its optimal discriminatory power was observed in adult dogs (ie, > or =12 months of age).     

Ecology of soil springtails (Collembola, Insecta) from pine woods and Rhododendron shrublands in the Central and Eastern Pyrenees (North Spain)

The collembological composition of samples from the Central and Western Pyrenees (Northern Spain) was studied. Soils from two biotopes (pine forest and Rhododendron shrub) were studied in Nuria and Vallibierna, using different diversity indices and multivariate analyses. Ten species were found that were endemic to the Iberian Peninsula. Three of these are exclusive to the Pyrenees: Ceratophysella elegans, Hypogastrura dasiensis and Protachorutes pyrenaeus. The greatest diversity was observed in the soils of Rhododendron, above all at Nuria. Collembola were most poorly represented in the pine forest of Vallibierna, where the endemic Hypogastrura meridionalis was the dominant species. Multivariate analyses indicated that the latter species characterizes this pine forest and separates it from all other biotopes studied. The evenness (E) was most pronounced in Nuria, where Folsomia manolachei was the characteristic species.     

Postlarvae and juveniles of a selected line of Penaeus stylirostris are resistant to infectious hypodermal and hematopoietic necrosis virus infection

A susceptibility study of postlarvae (PL) and juvenile Super Shrimp®, a selected line of Penaeus stylirostris, was conducted to compare their resistance to infectious hypodermal and hematopoietic necrosis virus (IHHNV) infection to that of a specific pathogen free (SPF) population of P. vannamei. Super Shrimp® PLs were fed with IHHNV-infected shrimp tissue for 2 days and then maintained on a pelletized ration for an additional 28 days. PLs were sampled at days 0, 1, 2, 3, 4, 6, 10, 15, 20, 25 and 30. There was no apparent mortality during the experimental period. Tissue DNA extracted from the PLs was analyzed for the presence of IHHNV by PCR. Low levels of IHHNV were detected only in DNA extracts from samples at days 1, 2, and 3. No IHHNV DNA was detected from days 4 to 30. The days that the PLs were weakly IHHNV-PCR positive were during the period that they were being fed with IHHNV-tissue, and thus, the IHHNV DNA signal was suspected to be from the infected tissue used as a feed. Through both histology and in situ hybridization, we confirmed that tissues of Super Shrimp® PLs were not infected with IHHNV. PCR results of another IHHNV challenge study with juveniles of Super Shrimp® were similar to those with PLs. These results indicate that IHHNV did not replicate in the PL and juvenile Super Shrimp®. In contrast, P. vannamei juveniles, which were used as a positive control, showed a more intense IHHNV infection, as determined by PCR detection, beginning at 6 days postchallenge and increasing throughout the remainder of the study. In addition, the IHHNV-infected P. vannamei at 30 days postchallenge showed histological changes characteristic of IHHNV infection and had a positive reaction for IHHNV with in situ hybridization. Our studies show that Super Shrimp® are resistant to IHHNV infection. This is the first unequivocal demonstration of resistance to viral infection in shrimp.     

Large Scale Evaluation of Primers for Diagnosis of Rupestris Stem Pitting Associated Virus-1

The unavailability of adequate immunological reagents has prevented the use of ELISA for the diagnosis of rupestris stem pitting disorder of grapevines. In this work, the performance of five primer pairs for broad-scale detection of rupestris stem pitting associated virus-1 by RT-PCR using ds-RNA templates was compared and contrasted with biological indexing. The virus was widespread among the budwood of 35 Portuguese grapevine varieties assayed, with a prevalence of 85%. The biological assay proved to be unreliable as an index of infection due to the high number of false negatives. Five sets of primers were assayed and compared by means of their relative sensitivity and negative predictive value. The primer pair specific for the coat protein gene was excluded because of the difficulty in identifying the specific amplified product. From the other four primer pairs, those specific for the helicase domain of the putative polymerase gene had the highest sensitivity and negative predictive value. However, a high confidence in the assay, as desirable for a certification scheme, could not be obtained by the sole use of this primer pair. An additional pair should be used in a separate or in a multiplex RT-PCR reaction.     

Analysis on the daily courses of water potential of nine woody species from Cerrado vegetation during wet season

IntroductionAS the concept of water pot6ntial (% was introduced by Saltyer (1967), there were some argumentson it among some physiologist. Some physiologistsopposed it beCause they believed Tvalue might notbe the beSt parameter for describing physiologicalprocesses. However, this concept has been accept6dand used by most plant physiologists for many years(Kramer 1988, Schulze et al. 1988, Passioura 1988,Boyer 1989).ACcording tO our experience (Prado et al. 1994,1995), we believed-t.hat th…     

Qualitative resistance of Hevea to Phyllachora huberi P. Henn

Qualitative observations of Hevea spp. resistance to Phyllachora huberi were carried out on 200 clones in a collection and 21 full-sib progenies under natural conditions of infestation. A total of 42 clones, mostly originating from the natural range of the Hevea genus, and at least two species (H. brasiliensis and H. benthamiana) revealed total resistance to the parasite. For nine of the thirteen `resistant ×susceptible' and `resistant × resistant' progenies studied, the ratio of susceptible: resistant plants suggested the existence of a total resistance mechanism produced by a dominant allele at a single locus for the P. huberi race(s) present at the study site. For three of the progenies involving the same resistant parent, it was possible to locate the gene (called Phr) at 14.7 cm from the adhisozyme locus. This revised version was published online in July 2006 with corrections to the Cover Date.     

Anti-leishmanial and immunomodulatory activities of extracts from Portulaca hirsutissima and Portulaca werdermannii

Ethyl acetate and chloroform extracts from aerial parts of Portulaca werdermannii and P. hirsutissima were tested in lymphoproliferation assays and axenic cultures of Leishmania amazonensis and Trypanosoma cruzi. Both extracts of P. werdermannii and P. hirsutissima had a potent inhibitory activity on lymphocyte proliferation. On the contrary, only the chloroformic extract of both plants inhibited L. amazonensis growth, without effect on T. cruzi cultures. These results indicate these Portulaca species as potential sources of new active molecules for the treatment of leishmaniasis and immune-mediated pathologies.     

Migration and escapement of silver eel males,Anguilla anguilla,from a southwestern European river

The catadromous life cycle of the European eel encompasses a spawning migration to the Sargasso Sea. Prior to their migration, eels develop a silver coloration being referred to as “silver eels.” Due to the dramatic European eel recruitment decline, it is crucial to quantify silver eel escapement to evaluate the success of measures taken under Eel Management Plans (Regulation EC (1100/2007)). Thus, the percentage of silver eels escaping from the River Mondego (Portugal) was estimated during two consecutive spawning seasons (2014–2016) and their migratory behaviour was studied. Thirty-six male silver eels were tagged with acoustic transmitters and their downstream migration was tracked using automatic receivers deployed at four locations along the river course, from the first impassable obstacle up to the river mouth (67 km). Among the tagged eels, 15 (42%) escaped to the sea. In both years, individuals displayed faster migration speed in the downstream reaches of the river. BRT (“Boosted Regression Trees”) models were used to explain downstream migration and escapement of silver eels. The analyses revealed that the downstream migration is triggered by several environmental variables with water conductivity as the most influential predictor. Escapement of eels from the estuary occurred a few hours after their arrival and was primarily explained by the offshore wind intensity, which promotes a current in the coast that may favour their transport to the open sea. These findings contribute to a better understanding of silver eel migration in southern latitudes and highlight and reinforce the need to monitor spawner escapement.