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201.
Babesia ovis isolated in Extremadura (Spain) was the subject of a serological study in experimentally inoculated sheep. The first antibody titres, determined by the indirect fluorescent antibody (IFA) test, were observed 7-8 days post infection (p.i.) in all animals except the splenectomized group, in which the only animal that survived showed antibody response 10 days p.i. A faster response following challenge was observed in sheep which were seropositive before inoculation, which suggests the existence of an antigen memory. The highest titres were reached 16-25 days p.i., and subsequently began to fall, reaching minima at the end of the experimental period (330 days p.i.). The chronic carrier state in experimental B. ovis infection had a duration of at least 2 years. Passive transmission of antibodies from experimentally infected mothers to newborn lambs was also detected. Antibody levels were observed for a period not longer than 2 months after birth.  相似文献   
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Incidence of peach [Prunus persica (L.) Batsch] tree mortality attributed to Armillaria root disease was assessed from 2009 to 2011 in 15 orchards in the State of Mexico, Mexico. Incidence increased gradually every year of assessment, reaching average values of 9.7, 15.3 and 20.3% tree mortality and 23.2, 24.7 and 28.3% disease‐impacted area of the orchards during 2009, 2010 and 2011, respectively. The cultivars ‘Nemaguard’ and ‘Criollo of La Goleta’, a local rootstock used in the region, were both susceptible to the disease. To identify species of Armillaria isolated from infected peach trees, two nuclear rDNA regions (partial 5.8S‐ITS2‐LSU D‐domains and partial 3′ LSU‐IGS1) and the translation elongation factor‐1α (tef‐1α) gene were sequenced and compared with sequences of known Armillaria species. DNA sequence analysis from 49 Armillaria isolates revealed that five isolates (10.2%) were Armillaria mellea and eight isolates (16.3%) were Armillaria gallica. DNA sequences from the remaining 36 isolates (73.5%) showed no close similarity to Armillaria sequences in GenBank, and apparently represent an undescribed Armillaria species. This undescribed species was the most widely distributed in the region of study. Separate phylogenetic analyses of the LSU region (D1–D3 domains concatenated with the partial 3′ end) and the tef‐1α region show that the undescribed species is quite distinct from other Armillaria spp. reported in North America.  相似文献   
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Tropical Animal Health and Production - The aim of the present study was to develop and evaluate an equation to predict body weight (BW) using hip width (HW) in Pelibuey ewe lambs and ewes. Five...  相似文献   
206.
Nephrosplenic entrapment is a commonly diagnosed cause of acute colic that may be corrected using surgical or non-surgical methods and has a good prognosis for survival. Intravenous administration of phenylephrine at doses ranging from 20–60 μg/kg given over 5–15 min often followed by forced exercise, various rolling techniques under general anaesthesia, or a combination of therapies has been reported. Correction of the entrapment via exploratory celiotomy may be challenging in certain cases and is hampered by marked splenic enlargement. The case report by Loomes and Anderson (2019) in this issue described a novel method of reducing the size of the spleen by direct intra-splenic injection of phenylephrine, in a case non-responsive to intravenous phenylephrine administration, which facilitated surgical correction of the nephrosplenic entrapment.  相似文献   
207.
A dog presented with cutaneous nodules, enlarged lymph nodes and oedema in limbs, face and abdomen. The diagnosis of visceral leishmaniasis was established by identification of Leishmania amastigotes within macrophages from skin and popliteal lymph node biopsies. At necropsy, lesions were found in different organs, but it was particularly striking to observe large areas of pallor in the myocardium. Histological examination revealed an intense chronic inflammatory reaction in many organs, and numerous macrophages were found to contain amastigote forms of Leishmania. The inflammatory reaction was especially severe in the heart, where large areas of the myocardium appeared infiltrated with huge numbers of mononuclear immune cells, causing cardiac muscle atrophy and degeneration. Despite the severe inflammation, the number of parasitized macrophages was low in the myocardium, as revealed by immunohistochemical staining of Leishmania amastigotes. Because cardiac involvement is not usually described in this condition, this dog represents a very rare case of canine visceral leishmaniasis with affection of the myocardium.  相似文献   
208.
Birds from the Almuñecar ornithological garden (Granada, Spain) were surveyed from June 2006 to May 2007 to establish programmes to prevent, control, and treat intestinal and haematic parasites. A total of 984 faecal samples and 41 samples of blood were collected from Psittacidae, Cacatuidae, Phasianidae, and Anatidae. One or more intestinal parasites were identified in 51.6% of the samples. Blood parasites were found in 26.8% of the birds examined. The most frequent pathogenic endoparasites were coccidians, such as Cyclospora sp. (4.5%), Eimeria sp. (4.1%) and Isospora sp. (2%) and helminths such as Capillaria sp. (10. 1%), Ascaridia sp. (4.9%) and Heterakis gallinarum (4.9%). All the parasites varied with season but the most were found year round. Multiple parasitic infections by intestinal parasites were common, with 196 of 984 faecal samples having 2–5 intestinal parasites. The most frequent cases of multiple parasitism were Blastocystis plus Entamoeba sp. and Blastocystis plus Cyclospora sp. The haematic protozoa detected were Haemoproteus sp. (17%) and Plasmodium sp. (7.3%). Multiple parasitism by Haemoproteus sp. and Plasmodium sp. was detected in 1 sample of Gallus gallus. After each sampling, some of the affected animals were treated according to our results, and the corresponding programmes of prevention and control were designed.  相似文献   
209.
This study evaluated the effect of supplementation of a plant ingredients‐based diet with two levels of commercially digestive enzyme products: Synergen? and Natugrain® on the apparent digestibility coefficients (ADCs) of nutrients and on digestive enzyme activities in European seabass (Dicentrarchus labrax) juveniles. A control diet was formulated with 450 g/kg CP (200 g/kg from fish meal + 800 g/kg from plant protein) and 180 g/kg CL (fish oil), and four other diets were made similar to the control but supplemented with 0.2 g/kg or 0.4 g/kg of Synergen? and Natugrain®. Digestive enzyme activities were not affected by dietary treatments. Nevertheless, chyme pH along the intestine of fish fed the Natugrain®‐supplemented diets was reduced. The ADC of nutrients increased with exogenous digestive enzyme supplementation, with the highest ADC values being observed for the 0.4 g/kg Natugrain® diet. The ADC of dry matter, protein, lipids, energy and phosphorus in this diet were 26%, 6%, 4%, 16% and 63% higher, respectively, than in the control diet. Overall, diet supplementation with exogenous enzyme complexes seems to have high potential for improving the utilization of plant feedstuff‐rich diets for seabass juveniles. This study revealed that Natugrain® was more effective than Synergen? in improving the ADC of nutrients and energy in European seabass juveniles.  相似文献   
210.
Aflatoxicosis is a growing problem in aquaculture. A 42‐day study was designed to evaluate the efficacy of conjugated linoleic acid (CLA) and curcumin (CUR) to protect juvenile Pacific white shrimp (Litopenaeus vannamei) from aflatoxins. Growth parameters along with alkaline phosphatase (ALP) and glutathione S‐transferase (GST) activities were measured. Shrimps (36) with an average weight of 76 ± 0.9 mg were randomly allocated in eight experimental groups. Non‐contaminated diet (NCD) and aflatoxin‐contaminated diet (ACD) at 200 μg/kg were prepared. ACD was used to prepare six diets supplemented with CLA (4, 5 or 6 g/kg) and CUR (0.15, 0.2 and 0.3 g/kg). ACD reduced feed intake, growth rate and nitrogen retention efficiency, and increased ALP and GST activity. Improved nitrogen retention was observed for all groups feed with CLA. CUR supplementation at 0.2 g/kg increased feed intake and growth rate while at 0.15 g/kg increased nitrogen retention. ALP activity was reduced in all CUR groups and in 5 and 6 g/kg CLA groups. Reduction in GST activity was observed in 0.15 and 0.2 g/kg CUR groups and 4 g/kg CLA group. CLA supplementation and CUR supplementation can be beneficial to protect juvenile shrimp against aflatoxins.  相似文献   
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