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61.
Insects are currently being considered as a novel protein source for animal feeds, because they contain a large amount of protein. The larvae of Tenebrio molitor (TM) have been shown to be an acceptable protein source for broiler chickens in terms of growth performance, but till now, no data on histological or intestinal morphometric features have been reported. This study has had the aim of evaluating the effects of dietary TM inclusion on the performance, welfare, intestinal morphology and histological features of free‐range chickens. A total of 140 medium‐growing hybrid female chickens were free‐range reared and randomly allotted to two dietary treatments: (i) a control group and (ii) a TM group, in which TM meal was included at 75 g/kg. Each group consisted of five pens as replicates, with 14 chicks per pen. Growth performance, haematological and serum parameters and welfare indicators were evaluated, and the animals were slaughtered at the age of 97 days. Two birds per pen (10 birds/treatment) were submitted to histological (liver, spleen, thymus, bursa of Fabricius, kidney, heart, glandular stomach and gut) and morphometric (duodenum, jejunum and ileum) investigations. The inclusion of TM did not affect the growth performance, haematological or serum parameters. The morphometric and histological features were not significantly affected either, thus suggesting no influence on nutrient metabolization, performance or animal health. Glandular stomach alterations (chronic flogosis with epithelial squamous metaplasia) were considered paraphysiological in relation to free‐range farming. The observed chronic intestinal flogosis, with concomitant activation of the lymphoid tissue, was probably due to previous parasitic infections, which are very frequently detected in free‐range chickens. In conclusion, the findings of this study show that yellow mealworm inclusion does not affect the welfare, productive performances or morphological features of free‐range chickens, thus confirming that TM can be used safely in poultry diets.  相似文献   
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The purpose of the present study was to detect leptospiral DNA by PCR in semen and urine samples of stallions to test for venereal transmission in horses. A total of 10 stallions from four herds were studied, and sampling was conducted in semen and urine for culture and PCR and serum for serology. From the 10 serum samples tested, 6 (60%) were seroreactive. No pure culture was obtained, but leptospiral DNA was detected by PCR in 50% of the semen samples and 30% of urine samples. The present study aimed to detect leptospiral DNA by PCR in semen and urine samples of stallions to test for venereal transmission in horses. Based on these findings, we suggest that there is potential transmission of leptospirosis in horses by sexual transmission.  相似文献   
65.
A capture operation to ascertain health status in free-ranging buffaloes from six different areas in the Caprivi Strip in the northeast corner of Namibia was conducted in October 2009. Basic information on the ticks and tick-borne pathogens normally found in wildlife from this area are scarce. The objective of this study was to assess the host status of African buffaloes, Syncerus caffer, for ixodid ticks and two selected tick-borne pathogens in the Caprivi Strip, a key area bordering Angola, Zambia, Botswana, and Zimbabwe. Four different tick species have been identified among the 233 collected specimens, and, of 95 tested buffaloes, 54 (57%) were positive for Theileria parva, whereas only 3 (3%) showed evidence of being infected with Ehrlichia ruminantium.  相似文献   
66.
This study examined the effect of treating mares with equine pituitary extract (EPE) in combination with human chorionic gonadotropin (hCG; EPE/hCG) on the recovery rate of immature oocytes by ovum pick-up (OPU) and on oocyte morphology. Ten mares were subjected to each of two treatments in a random sequence: superstimulated with EPE (25 mg, twice daily) and treated with hCG (2,500 IU) or control (no exogenous treatment). The cytoplasmic morphology of oocytes recovered was evaluated through transmission electron microscopy. Follicular fluid was collected at aspiration for progesterone analysis, which was performed by radioimmunoassay. The EPE/hCG did not increase the oocyte recovery rate from immature follicles when compared with the controls (15.5% and 16.7%, respectively). A significantly higher oocyte recovery rate per mare was observed (70% versus 50%). However, precocious granulosa cell expansion was observed with EPE/hCG treatment in contrast to the control (64.4% and 33% of follicles with expanded cumulus, respectively), and increased intrafollicular progesterone concentration was also seen (158.80 ng/mL versus 82.05 ng/mL). The ultrastructural analysis of oocytes from both groups showed morphologic features related to immaturity. Numerous vesicles containing cortical granules were found, distributed in clusters into the cytoplasm, and junctional complexes were still seen between oocyte and granulosa cells. In conclusion, EPE/hCG treatment induced some follicular modifications, but the recovery rate was not increased. All oocytes examined presented signs of immaturity.  相似文献   
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This study describes a duplex real-time polymerase chain reaction (PCR) assay for the detection and differentiation between Dirofilaria immitis and Dirofilaria repens in dog blood and mosquitoes. Regions of a cytochrome oxidase 1 (cox1) mitochondrial DNA fragment and the second internal transcribed spacer (ITS-2) of nuclear ribosomal DNA were amplified from microfilariae and adult worm samples, using a sensitive SsoFast? EvaGreen(?) based real-time PCR method coupled with melting-curve analysis. The limit of the real-time PCR in detecting microfilaria and adult worm DNA was also tested both in dog blood and in artificially infected microfilarial. Two peaks at different melting temperatures (T(m)) for D. immitis (mean ± SD=75.7 ± 0.3°C) and D. repens (mean ± SD=70 ± 0.7°C), respectively, were obtained for microfilarial and adult positive controls of both species when examined separately and together. The real-time PCR protocol was also efficient in detecting microfilarial and adult DNA of both species when tested in samples spiked with DNA from Aedes albopictus, in Aedes aegypti experimentally infected by D. repens and in Culex pipiens naturally infected by D. repens and D. immitis. The high sensitivity of real-time PCR confirmed its reliability in detecting small amounts of genomic DNA either in dog blood or mosquitoes (2.5 pg/μl and 3 × 10(-1)pg/μl for D. immitis and D. repens, respectively). This assay is proposed as a tool for the epidemiological surveillance of the two most important Dirofilaria species in areas where they are endemic and sympatric.  相似文献   
69.
The aims of this study were to develop a dental evaluate any oral cavity disease, develop gypsum models of the dental arches, and to register the occlusions found in coatis (Nasua nasua) in captivity Formulation of the dental chart was assisted by intraoral radiographs from the head of an adult coati cadaver of the same species with the following dental formula.: I 3/3, C 1/1, P 4/3, M 2/2. Seven live coatis of the Nasua nasua species were evaluated. Five of the seven coatis presented with various dental abnormalities as follows: dental plaque (71.4 0%), gingivitis (71.4 %), periodontitis (57.1 %), dental stain (42.9 %), dental abrasion (57.1 %), dental fracture (57.1 %), pulp exposure (42.9 %), malocclusion (57.1 %) and supernumerary teeth (14.2 %).  相似文献   
70.

Background

The authors report the first case of feline gastric actinomycosis associated with infection by Actinomyces hordeovulneris.

Case presentation

A 4-year-old, neutered male, semi-feral European cat, with a 1 year history of chronic vomiting, was referred to the clinic. Abdominal ultrasound examination identified a hypoechoic focal transmural thickening with loss of normal wall layering and hyperechoic speckles at the gastric body. Initial gastroscopic examination showed a tumour-like gastric mass with an ulcerated depression at the level of the greater curvature. Histologic examination of endoscopic biopsy specimens was consistent with a severe lymphoplasmacytic gastritis. After 2 months, due to persistence of abdominal discomfort, surgical exploration and intraoperative sampling of gross abnormalities was recommended. Full thickness gastric wall biopsies, and fine needle aspiration of the gastric thickening and gastric lymph node, were performed. Histopathological examination identified a transmural pyogranulomatous gastritis. Aspirate samples of the gastric wall cultured positive, with colony morphology, biochemical testing and PCR of the 16 s rRNA gene compatible with Actinomyces hordeovulneris. After 4 months of treatment with cefovecin (8 mg/kg subcutaneously every 14 days), the vomiting completely resolved, as well as the ultrasonographic gastric alteration.

Conclusion

This case report of feline gastric actinomycosis, caused by Actinomyces hordeovulneris, suggests that gastric bacterial infection should be considered in cases of focal gastric wall thickening associated with chronic vomiting in the cat, which may otherwise closely resemble neoplastic disease. Once a diagnosis of actinomycosis was obtained, a correct treatment with antibiotic therapy can resolve it.
  相似文献   
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