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81.
Background: The present work aimed at evaluating the effect of the dietary replacement of soybean oil(S) by two types of insect fats extracted from black soldier fly larvae(H, Hermetia il ucens L.) and yel ow mealworm larvae(T, Tenebrio molitor L.) on growth performance, nutrient digestibility, blood parameters, intestinal morphology and health of growing rabbits.Methods: At weaning, 200 crossbred rabbits(36 days old) were allotted to five dietary treatments(40 rabbits/group): a control diet(C) containing 1.5% of soybean oil and four experimental diets where soybean oil was partially(50%) or totally(100%) substituted by H(H50 and H100) or T(T50 and T100) fats. Total tract digestibility was evaluated on 12 rabbits per treatment. The growth trial lasted 41 d and, at slaughtering(78 days old), blood samples were collected from 15 rabbits per treatment, morphometric analyses were performed on duodenum, jejunum and ileum mucosa,and samples of liver, spleen and kidney were submitted to histological evaluation.Results: No difference was observed between the control and the experimental groups fed insect fats in terms of performance, morbidity, mortality and blood variables. The addition of H and T fats did not influence apparent digestibility coefficients of dry matter, protein, ether extract, fibre fractions and gross energy. Gut morphometric indices and organ histopathology were not affected by dietary inclusion of H and T fats.Conclusions: H and T fats are suitable sources of lipid in rabbit diets to replace soybean oil without any detrimental effect on growth performance, apparent digestibility, gut mucosa traits and health.  相似文献   
82.
Methotrexate may be an alternative to ciclosporin in the treatment of canine atopic dermatitis (cAD) as suggested by recent data. The aim of the study was to investigate both the tolerance and the pharmacokinetic behavior of methotrexate (MTX) in plasma, following intravenous (i.v.), subcutaneous (s.c.) or oral (OR) administration over several weeks. Six healthy dogs were given oral MTX once a week, respectively, per dog at 2.5 mg/1 week, 5 mg/4 weeks, 7.5 mg/3 weeks, 10 mg/6 weeks and 12.5 mg/5 weeks. No clinically relevant abnormalities of laboratory parameters were noticed. A high inter‐individual variation of MTX plasma concentration was observed with a suspicion of saturation phenomenon in absorption. To compare with other routes of administration, six healthy beagle dogs followed a crossover design study at 7.5 mg per dog MTX. The absolute bioavailability was 93% for SC injection and 30% for the oral route. The inter‐individual variability was quite low following SC administration compared to oral route. Just as in human, given the substantial variability of oral absorption, clinicians cannot assume consistent oral bioavailability of MTX. Therefore, they may consider switching dogs to the SC route in case of absence of clinical response with a weekly oral dose.  相似文献   
83.
    
Ohne ZusammenfassungMit 1 Abbildung  相似文献   
84.
In grazing systems, heterogeneous distributions of forage resources and faeces result in localised accumulations of nutrients and parasites (both macroparasites and microparasites), creating trade-offs between the costs of exposure to infestation or infection and the benefits of nutrient intake. Each contact between livestock and faeces in the environment is a potential parasite/pathogen transmission event. Thus, herbivores must make foraging decisions in complex environments which will affect their intake of both nutrients and parasites. However, the pattern of forage and faecal resources in agricultural environments will also be affected by the grazing management system in place. The aim of this study was to investigate the effect of grazing management on the risk of infection/infestation to livestock. We used a spatially explicit individual based stochastic foraging model to simulate livestock contact (both grazing and investigative) with faeces in the environment. The model was parameterised to simulate cattle grazing under three types of grazing management: set stock (i.e. where sward growth and cattle intake are in equilibrium in a single field); a two pasture rotation grazing system with increasing number of rotations; and a rotational grazing system with two rotations and increasing subdivisions of the pasture. Overall the amount of cattle contact with faecal-contaminated patches was similar in both set stocking and rotational grazing scenarios, suggesting no difference in the risk of infection or infestation between the different systems. However, the timing and absolute amounts of peak contact varied greatly indicating that different grazing management systems expose livestock to risks of different types of parasites at different times of the grazing season. Intensive rotational systems with small pasture blocks (especially the first grazing period) maximised livestock contact with fresh faeces, and thus exposure to microparasites (e.g. bacterial pathogens). Livestock re-entering pasture blocks in rotational systems and set stocked livestock had the highest contact with old faeces and thus have a greater risk of macroparasite transmission (gastrointestinal nematodes). This study highlights how livestock management affects the highly dynamic interaction between livestock and distributions of parasites in the environment and thus the levels of livestock exposure to parasites and pathogens via the faecal–oral route.  相似文献   
85.
This study summarizes the diagnostic findings from all anemic cats diagnosed with hemotropic mycoplasma (HM) infections at the Western College of Veterinary Medicine — Veterinary Teaching Hospital between 1996 and 2005. The objectives were to determine the frequency of HM-induced anemia among all cats presented with anemia during this period, the clinical findings and risk factors associated with clinical HM infection, and factors affecting or predicting survival. Medical records were examined from 23 cats with HM-induced anemia from the total of 170 cats diagnosed with anemia during this period. The frequency of HM-induced anemia was 14% (23/170) among all anemic cats. Cats with HM-induced anemia were less likely to be purebred (P = 0.04) than other cats with anemia. Of the cats with HM-induced anemia, those with positive retroviral status (P = 0.01), concurrent illness (P < 0.01), or lack of erythroid regeneration (P = 0.01) were most likely to die. The 1-year survival of HM-infected cats was 65% (13/20).  相似文献   
86.
In the present study, comprehensive data on the seroprevalence of Corynebacterium (C.) pseudotuberculosis infections in goats are presented for Baden-Wuerttemberg, a Federal State of Germany, for the first time. As a prerequisite, ELISAs based on a recombinant phospholipase D (rPLD) and whole cell antigens (WCA) were designed and validated yielding sensitivity values of 81% and 97% and specificity values of 98% and 99%, respectively. Immunisation trials in goats demonstrated a significant production of antibodies to rPLD but an evidently lower antibody production to WCA as determined in the corresponding ELISA. Moreover, immunisation with rPLD resulted in the formation of antibodies, which were also detected in the WCA ELISA. In contrast, this phenomenon was not observed with the rPLD ELISA after immunisation with WCA. Implementation of the rPLD and WCA ELISAs in a broad-based seroprevalence study in Baden-Wuerttemberg revealed positive reactions in both ELISAs in 13.2% of the 1771 goat sera tested. In 53.7% of 121 herds of which five or more animals were tested per herd there was at least one animal that showed a positive reaction in both tests.  相似文献   
87.
OBJECTIVE: To validate use of magnetic resonance images (MRIs) for measurement of equine articular cartilage and subchondral bone thickness by comparison with measurements in histologic specimens. SAMPLE POPULATION: 32 cadaveric carpal joints from 16 horses. PROCEDURE: Magnetic resonance imaging was performed by use of 3-dimensional fast spoiled gradient echo (SPGR) and T2* 3-dimensional fast gradient echo (GRE) pulse sequences with and without fat saturation. Standard sites on the medial and lateral facets of the intermediate, radial, and third carpal bones were used for subchondral bone and articular cartilage thickness measurements. Digital image analysis software was used for MRI measurements 10 mm from the dorsal extent and perpendicular to the articular surface. Histomorphometric measurements of hyaline, calcified cartilage, and subchondral bone thickness were obtained at selected sites. Comparisons between histomorphometric and MRI measurements and between magnetic resonance pulse sequences were evaluated. RESULTS: There were significant correlations between GRE and SPGR and SPGR and histologic measurements of articular cartilage, with no significant difference between measurements and good agreement. When calcified cartilage was excluded from the histologic measurement, MRI measurements were significantly greater than histologic measurements. For subchondral bone thickness, there was significant correlation between GRE and SPGR but GRE was significantly greater than SPGR measurements. Histomorphometric and MRI measurements were strongly correlated and not significantly different. CONCLUSIONS AND CLINICAL RELEVANCE: Magnetic resonance imaging provides a good representation of cartilage and subchondral bone thickness, supporting its use in the study and clinical diagnosis of osteochondral structure and alteration.  相似文献   
88.
Injury of the distal aspect of the deep digital flexor tendon (DDFT) is a recognized cause of lameness, but diagnosis is difficult. This study aimed to improve understanding of DDFT morphology and pathology using retrospective evaluation of magnetic resonance (MR) images. We hypothesized that: (1) The distal aspect of the DDFT in normal horses would have a repeatable proximal/distal pattern and symmetry between limbs and between lobes; (2) DDFT dimensions would be related to bodyweight, navicular bone dimensions and hoof size; (3) this symmetry and pattern would be lost in DDFT injury; and (4) DDFT size would increase with injury. MR images of 64 live horse limbs, 26 with no identified DDFT lesion and 38 with identified DDFT abnormalities, and 19 normal cadaver limbs were analyzed. Using standardized transverse images, measurements of DDFT cross-sectional area, medial-lateral (ML) width and dorsal-palmar depth were obtained at six preselected sites. A uniform distal to proximal shape pattern was identified in all horses. The flattened crescent shape at the insertion changed to a deeper bilobed shape more proximally, with the mid-navicular area having the greatest cross-sectional area. Strong ML (P < 0.0006) and left/right symmetry (P < 0.02) were observed. In addition, there was a strong association between DDFT cross-sectional area and horse weight (P = 0.005) and between DDFT and navicular bone ML width (P = 0.004). Symmetry between sides or between lobes was lost at sites with a unilateral lesion and correlation between horse weight and DDFT cross-sectional area was lost in the presence of lesions. DDFTs with core lesions had a consistent increase in cross-sectional area overall, but other lesion types had no significant increase in size. The shape and symmetry seen in normal tendons could be related to the mechanical demands placed upon individual lobes. The limited increase in cross-sectional area with injury may be explained by the restrictive structures of the hoof, possibly explaining the ongoing pain seen in such lesions.  相似文献   
89.
Transmissible spongiform encephalopathies (TSEs) in animals include, among others, bovine spongiform encephalopathy (BSE), scrapie, chronic wasting disease, and atypical forms of prion diseases. Diagnosis of TSEs is based on identification of characteristic lesions or on detection of the abnormal prion proteins in tissues, often by use of their partial proteinase K resistance property. Correctly sampling of target tissues is of utmost importance as this has a considerable effect on test sensitivity. Most of the rapid or screening tests are based on ELISA or Western immunoblot (WB) analysis, and many are officially approved. Confirmatory testing is normally performed by use of histologic examination, immunohistochemical analysis, certain WB protocols, or detection of prion fibrils by use of electron microscopy (scrapie-associated fibril). The discriminatory methods for diagnostic use are mostly based on WB technology and provide initial identification of the prion strain, particularly for differentiation of BSE from scrapie in small ruminants. Definitive prion strain characterization is performed by use of bioassays, usually in mice. A burgeoning number of transgenic mice have been developed for TSE studies. Development of new tests with higher sensitivity and of more reliable diagnostic applications for live animals tested for food safety reasons is a rapidly developing field. Ultimately, the choice of a test for TSE diagnosis depends on the rationale for the testing.  相似文献   
90.
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