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61.
Few data exist on the parasites of ratites, especially from regions within their natural range. It is only recently that extensive studies on the parasites of ostriches (Struthio camelus) have been published, mainly from European countries where commercial farming has expanded. Two species of ratites are native in South America: the lesser rhea also known as Darwin's rhea (Rhea pennata) and the greater rhea (Rhea americana). Both species are considered near threatened by the IUCN and are included in the CITES’ Appendices I and II, respectively. Parasitological studies have conservation implications, as they allow us to assess the risk of transmission of pathogens from farmed ratites to wild populations. In this study 92 faecal samples from greater rheas and 55 faecal samples from lesser rheas from different localities in Argentine were analyzed to determine their gastrointestinal parasites. In greater rheas the protozoa (Balantidium coli-like and Entamoeba spp.) and helminths (Fasciola hepatica and Deletrocephalus spp.). The protozoa had not previously been cited as parasites of greater rheas in South America. Cysts and/or trophozoites of B. coli-like were found in 16.3% of the samples, while the prevalence of the remaining parasites was below 10%. Lesser rheas harbored the protozoa B. coli-like, Entamoeba spp. and Chilomastix spp. as well as F. hepatica and nematode eggs and larvae. B. coli-like cysts were found in 20.0% of the samples, while the prevalence of the other parasites remained below 5%. Some of them had not been cited as infecting lesser rheas yet.  相似文献   
62.
The average contents, in mg/kg edible portion (e.p.), of elements not considered for nutritional labeling in Spanish table olives were as follows: aluminum, 71.1; boron, 4.41; barium, 2.77; cadmium, 0.04; cobalt, 0.12; chromium, 0.19; lithium, 6.56; nickel, 0.15; lead, 0.15; sulfur, 321; tin, 18.4; strontium, 9.71; and zirconium, 0.04. Sulfur was the most abundant element in table olives, followed by aluminum and tin (related to green olives). There were significant differences between elaboration styles, except for aluminum, tin, and sulfur. Ripe olives had significantly higher concentrations (mg/kg e.p.) of boron (5.32), barium (3.91), cadmium (0.065), cobalt (0.190), chromium (0.256), lithium (10.01), nickel (0.220), and strontium (10.21), but the levels of tin (25.55) and zirconium (0.039) were higher in green olives. The content of contaminants (cadmium, nickel, and tin) was always below the maximum limits legally established. The discriminant analysis led to an overall 86% correct classification of cases (80% after cross-validation).  相似文献   
63.
Visceral leishmaniasis in captive wild canids in Brazil   总被引:1,自引:1,他引:0  
Visceral leishmaniasis (VL) is endemic in Belo Horizonte (State of Minas Gerais, Brazil). Leishmania sp. can naturally infect several species of mammals, and the domestic dog is the most important reservoir of the disease in South America. This report describes five cases of visceral leishmaniasis in Brazilian canids. Among 15 animals kept in captivity in a zoo in Belo Horizonte (State of Minas Gerais, Brazil), two animals, a bush dog (Spheotos venaticos) and a hoary zorro (Lycalopex vetulus) were serologically positive and developed clinical signs of VL, whereas three other canids, including a crab-eating fox (Cerdocyon thous), a maned wolf (Chrysocyon brachyurus), and a hoary zorro (Lycalopex vetulus) had positive serological results without clinical signs.  相似文献   
64.
We describe lesions in 29 adult domestic pigeons (Columba livia) poisoned with chlorophacinone, an indandione anticoagulant rodenticide. Birds were found dead in the field and in dovecotes after a wide-area treatment against common voles (Microtus arvalis) based on the dispersion in the open field of wheat grain treated with 0.005% chlorophacinone. At necropsy, most pigeons showed crops full of red-colored wheat grain, extensive subcutaneous hematoma in neck and breast zones, and hemorrhages in lungs and the coelomic cavity. Chlorophacinone was determined in liver samples by high-performance liquid chromatography with ultraviolet detection, and the mean (range) concentration was 11.2 (1.48-50.1) microg/g. Pigeons have a venous subcutaneous plexus in the neck zone (plexus venosus subcutaneus collaris), which has been described as an erectile tissue with a thermoregulation function. This case report describes a relationship between the subcutaneous hemorrhagic lesions and the plexus venosus collaris.  相似文献   
65.
Doppler ultrasound is a non-invasive technique that can be used to estimate vascular resistance by calculation of resistive index (RI) and pulsatility index (PI). Liver disease may increase renal RI and PI, and in humans with liver disease the indices are monitored to attain prognostic information. Systemic hypertension has been found in dogs with hepatic disease and is also related to increased renal vascular resistance in humans. The aim of this study was to examine renal vascular resistance increases in dogs with hepatic disease and to ascertain whether these may be related to blood pressure increases and biochemical parameters. Twenty dogs with hepatic disease were evaluated. The mean renal RI, PI, and systolic blood pressure were significantly higher than in normal animals. A positive correlation was found between the indices and alkaline phosphatase but not with systolic blood pressure. It is concluded that renal vascular resistance may increase in dogs with hepatic disease and in this study was above the limit value in 50% of the animals.  相似文献   
66.
Veterinary Research Communications - The epithelial growth factor receptors are transmembrane proteins with an important role in the neoplastic progression of tumors, and in this context, DCIS is...  相似文献   
67.
Ex situ collections offer the potential to reduce extinction risks, affording option to society in maintaining future breeding opportunities for productivity and heritage traits. However, how much should we be seeking to collect and conserve in gene banks, and where? We developed a mathematical model to optimize logistical decisions of breed conservation choices and to evaluate alternative scenarios for efficiently re‐allocating genetic materials currently stored in different European gene banks, allowing for cross‐country collections, cost and cryogenic capacity differentials. We show how alternative allocations for the breeds that are currently stored in 11 European gene banks could reduce overall conservation costs by around 20% by selecting cryogenic banks that have relatively lower combination of fixed and collection costs, and are geographically closer to collection regions. Our results show that centralizing collections in one gene bank would double the costs, relative to collective European collections approaches. We also calculate marginal costs of collections and show that increasing diversity within the gene banks implies in higher costs per conserved breed.  相似文献   
68.
Placenta is formed by a parenchyma rich in extracellular matrix (ECM), and this structure guarantees the proper development of the embryo and placental functioning. Recently, studies have focused on the characterization of ECM in the placenta and foetal membranes of different species. This work aimed to analyse the composition of the ECM and to quantify the types of collagens in its composition. For this, 33 chorioallantoic membranes were used at different gestational ages, which were grouped into five groups. Subsequently, haematoxylin–eosin staining, Masson trichrome and picrosirius were performed for histological analysis. Through the technique of polarized light, it was possible to quantify the total collagen present in the membranes and finally the immunohistochemical technique was performed to verify the presence of collagens and glycoproteins. It was possible to verify that the chorioallantoic membranes have, in all the gestational periods of the initial third of gestation, the same histological structures, being the most significant difference the membrane thickening that occurs gradually during the gestation. However, we notice the appearance of binucleate cells only from group II. In addition, it was verified that a gradual increase of collagen occurs until the group IV, yet from the group V begins to occur a decrease of this protein. In addition, collagen I, collagen III, fibronectin and laminin were present in all membranes. With this, we concluded that the buffalo chorioallantoic membrane presents ECM in constant remodelling at the beginning of gestation and can be used as biomaterial in works on regenerative biology.  相似文献   
69.
Cataracts are among the most common ocular diseases, and are a leading cause of vision loss in humans and dogs. Jack Russell Terriers (JRT) and Labrador Retrievers (LR) are among the most popular canine breeds in the United Kingdom, and also among the most affected by cataracts.This study aimed to analyze the clinical features and the surgical outcome of cataracts in JRT and LR in an ophthalmologic reference Veterinary Hospital in the United Kingdom. For that purpose, medical records from JRT and LR diagnosed with cataracts between January 2015 and December 2016 were retrospectively evaluated. Data related to identification, clinical history, preoperative features, and surgical outcomes were analyzed.Forty-four dogs (81 eyes), including 26 JRT and 18 LR, were enrolled in the study. Mean ages were 10.2 ± 3.2 years in JRT and 8.5 ± 3.7 years in LR. Twenty-eight (63.6%) were females and 16 (36.4%) were males. Most dogs (84.1%) presented with bilateral cataracts. Nuclear and cortical cataracts were the most prevalent type in both breeds (JRT: n?=?30, 61.2%; LR: n?=?16, 50.0%), although subcapsular cataracts were also frequent in LR (n?=?10, 31.3%). Significant differences in cataract location within the lens were detected between the two breeds (P?=?.002).Senile in JRT (n?=?7) and genetic in LR (n?=?7) were the most common etiologies. Concomitant ocular lesions were more frequent in dogs presented with cataracts in advanced stages, and included lens (n?=?18; JRT: n?=?15; LR: n?=?3) and retinal alterations (n?=?8; JRT: n?=?2; LR: n?=?6), and glaucoma (n?=?6; JRT: n?=?5; LR: n?=?1). Thirty-three animals (75.0%, 51 eyes) were submitted to phacoemulsification with intraocular lens placement. Of these, 28 eyes (54.9%; JRT: n?=?21; LR: n?=?7) were visual, 19 eyes (37.3%; JRT: n?=?11; LR: n?=?8) presented impaired vision and four eyes (7.8%; JRT: n?=?0; LR: n?=?4) were blind at last clinical record. Postoperative complications were detected in 11 eyes (21.6%), and were more frequent in dogs presented with cataracts in advanced stages.These results and the multifactorial nature of cataracts call for further studies to identify and characterize the variables in a broader assessment, including other breeds and influencing factors.  相似文献   
70.
Pejerrey is an important zooplanktivorous native fish of the Argentinean inland waters. It has been traditionally propagated for stocking purposes by relatively costly semi‐intensive and intensive methods. In this study, we evaluated the implementation of an extensive culture method by using floating cages in a shallow pampean lake. Four cages were installed in the Lacombe Lake and stocked with juveniles (16.24 ± 1.69 mm length) at 50 fish m?3 density for growing until the size of 150 mm, which is considered as a suitable size for stocking. Throughout the experiment, the temperature ranged between 10 and 26 °C and the zooplankton biomass ranged between 12 and 3269 μg dw L?1. The growth patterns in the length were similar in the four cages and directly related to the lake thermal conditions and zooplankton availability. The average final length after 315 days was 154.4 ± 8.8 mm. The survival rates ranged between 53.5% and 64.7% during the first 110 days and 11.1–25.7% at termination. Growth rate for the first 2 months was the highest documented for pejerrey culture. This simple technique offers the possibility to produce juvenile pejerrey at a low cost and provides the alternative of reinforcing the natural populations with fish already adapted to the natural environmental conditions.  相似文献   
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